source: project/chicken/trunk/pcre/pcre_compile.c @ 12117

Last change on this file since 12117 was 12117, checked in by Kon Lovett, 13 years ago

PCRE 7.8, use of "full" flonum-hash, new scheme-complete by Alex Shinn.

File size: 198.1 KB
Line 
1/*************************************************
2*      Perl-Compatible Regular Expressions       *
3*************************************************/
4
5/* PCRE is a library of functions to support regular expressions whose syntax
6and semantics are as close as possible to those of the Perl 5 language.
7
8                       Written by Philip Hazel
9           Copyright (c) 1997-2008 University of Cambridge
10
11-----------------------------------------------------------------------------
12Redistribution and use in source and binary forms, with or without
13modification, are permitted provided that the following conditions are met:
14
15    * Redistributions of source code must retain the above copyright notice,
16      this list of conditions and the following disclaimer.
17
18    * Redistributions in binary form must reproduce the above copyright
19      notice, this list of conditions and the following disclaimer in the
20      documentation and/or other materials provided with the distribution.
21
22    * Neither the name of the University of Cambridge nor the names of its
23      contributors may be used to endorse or promote products derived from
24      this software without specific prior written permission.
25
26THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36POSSIBILITY OF SUCH DAMAGE.
37-----------------------------------------------------------------------------
38*/
39
40
41/* This module contains the external function pcre_compile(), along with
42supporting internal functions that are not used by other modules. */
43
44
45#ifdef HAVE_CONFIG_H
46#include "config.h"
47#endif
48
49#define NLBLOCK cd             /* Block containing newline information */
50#define PSSTART start_pattern  /* Field containing processed string start */
51#define PSEND   end_pattern    /* Field containing processed string end */
52
53#include "pcre_internal.h"
54
55
56/* When DEBUG is defined, we need the pcre_printint() function, which is also
57used by pcretest. DEBUG is not defined when building a production library. */
58
59#ifdef DEBUG
60#include "pcre_printint.src"
61#endif
62
63
64/* Macro for setting individual bits in class bitmaps. */
65
66#define SETBIT(a,b) a[b/8] |= (1 << (b%8))
67
68/* Maximum length value to check against when making sure that the integer that
69holds the compiled pattern length does not overflow. We make it a bit less than
70INT_MAX to allow for adding in group terminating bytes, so that we don't have
71to check them every time. */
72
73#define OFLOW_MAX (INT_MAX - 20)
74
75
76/*************************************************
77*      Code parameters and static tables         *
78*************************************************/
79
80/* This value specifies the size of stack workspace that is used during the
81first pre-compile phase that determines how much memory is required. The regex
82is partly compiled into this space, but the compiled parts are discarded as
83soon as they can be, so that hopefully there will never be an overrun. The code
84does, however, check for an overrun. The largest amount I've seen used is 218,
85so this number is very generous.
86
87The same workspace is used during the second, actual compile phase for
88remembering forward references to groups so that they can be filled in at the
89end. Each entry in this list occupies LINK_SIZE bytes, so even when LINK_SIZE
90is 4 there is plenty of room. */
91
92#define COMPILE_WORK_SIZE (4096)
93
94
95/* Table for handling escaped characters in the range '0'-'z'. Positive returns
96are simple data values; negative values are for special things like \d and so
97on. Zero means further processing is needed (for things like \x), or the escape
98is invalid. */
99
100#ifndef EBCDIC  /* This is the "normal" table for ASCII systems */
101static const short int escapes[] = {
102     0,      0,      0,      0,      0,      0,      0,      0,   /* 0 - 7 */
103     0,      0,    ':',    ';',    '<',    '=',    '>',    '?',   /* 8 - ? */
104   '@', -ESC_A, -ESC_B, -ESC_C, -ESC_D, -ESC_E,      0, -ESC_G,   /* @ - G */
105-ESC_H,      0,      0, -ESC_K,      0,      0,      0,      0,   /* H - O */
106-ESC_P, -ESC_Q, -ESC_R, -ESC_S,      0,      0, -ESC_V, -ESC_W,   /* P - W */
107-ESC_X,      0, -ESC_Z,    '[',   '\\',    ']',    '^',    '_',   /* X - _ */
108   '`',      7, -ESC_b,      0, -ESC_d,  ESC_e,  ESC_f,      0,   /* ` - g */
109-ESC_h,      0,      0, -ESC_k,      0,      0,  ESC_n,      0,   /* h - o */
110-ESC_p,      0,  ESC_r, -ESC_s,  ESC_tee,    0, -ESC_v, -ESC_w,   /* p - w */
111     0,      0, -ESC_z                                            /* x - z */
112};
113
114#else           /* This is the "abnormal" table for EBCDIC systems */
115static const short int escapes[] = {
116/*  48 */     0,     0,      0,     '.',    '<',   '(',    '+',    '|',
117/*  50 */   '&',     0,      0,       0,      0,     0,      0,      0,
118/*  58 */     0,     0,    '!',     '$',    '*',   ')',    ';',    '~',
119/*  60 */   '-',   '/',      0,       0,      0,     0,      0,      0,
120/*  68 */     0,     0,    '|',     ',',    '%',   '_',    '>',    '?',
121/*  70 */     0,     0,      0,       0,      0,     0,      0,      0,
122/*  78 */     0,   '`',    ':',     '#',    '@',  '\'',    '=',    '"',
123/*  80 */     0,     7, -ESC_b,       0, -ESC_d, ESC_e,  ESC_f,      0,
124/*  88 */-ESC_h,     0,      0,     '{',      0,     0,      0,      0,
125/*  90 */     0,     0, -ESC_k,     'l',      0, ESC_n,      0, -ESC_p,
126/*  98 */     0, ESC_r,      0,     '}',      0,     0,      0,      0,
127/*  A0 */     0,   '~', -ESC_s, ESC_tee,      0,-ESC_v, -ESC_w,      0,
128/*  A8 */     0,-ESC_z,      0,       0,      0,   '[',      0,      0,
129/*  B0 */     0,     0,      0,       0,      0,     0,      0,      0,
130/*  B8 */     0,     0,      0,       0,      0,   ']',    '=',    '-',
131/*  C0 */   '{',-ESC_A, -ESC_B,  -ESC_C, -ESC_D,-ESC_E,      0, -ESC_G,
132/*  C8 */-ESC_H,     0,      0,       0,      0,     0,      0,      0,
133/*  D0 */   '}',     0, -ESC_K,       0,      0,     0,      0, -ESC_P,
134/*  D8 */-ESC_Q,-ESC_R,      0,       0,      0,     0,      0,      0,
135/*  E0 */  '\\',     0, -ESC_S,       0,      0,-ESC_V, -ESC_W, -ESC_X,
136/*  E8 */     0,-ESC_Z,      0,       0,      0,     0,      0,      0,
137/*  F0 */     0,     0,      0,       0,      0,     0,      0,      0,
138/*  F8 */     0,     0,      0,       0,      0,     0,      0,      0
139};
140#endif
141
142
143/* Table of special "verbs" like (*PRUNE). This is a short table, so it is
144searched linearly. Put all the names into a single string, in order to reduce
145the number of relocations when a shared library is dynamically linked. */
146
147typedef struct verbitem {
148  int   len;
149  int   op;
150} verbitem;
151
152static const char verbnames[] =
153  "ACCEPT\0"
154  "COMMIT\0"
155  "F\0"
156  "FAIL\0"
157  "PRUNE\0"
158  "SKIP\0"
159  "THEN";
160
161static const verbitem verbs[] = {
162  { 6, OP_ACCEPT },
163  { 6, OP_COMMIT },
164  { 1, OP_FAIL },
165  { 4, OP_FAIL },
166  { 5, OP_PRUNE },
167  { 4, OP_SKIP  },
168  { 4, OP_THEN  }
169};
170
171static const int verbcount = sizeof(verbs)/sizeof(verbitem);
172
173
174/* Tables of names of POSIX character classes and their lengths. The names are
175now all in a single string, to reduce the number of relocations when a shared
176library is dynamically loaded. The list of lengths is terminated by a zero
177length entry. The first three must be alpha, lower, upper, as this is assumed
178for handling case independence. */
179
180static const char posix_names[] =
181  "alpha\0"  "lower\0"  "upper\0"  "alnum\0"  "ascii\0"  "blank\0"
182  "cntrl\0"  "digit\0"  "graph\0"  "print\0"  "punct\0"  "space\0"
183  "word\0"   "xdigit";
184
185static const uschar posix_name_lengths[] = {
186  5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 6, 0 };
187
188/* Table of class bit maps for each POSIX class. Each class is formed from a
189base map, with an optional addition or removal of another map. Then, for some
190classes, there is some additional tweaking: for [:blank:] the vertical space
191characters are removed, and for [:alpha:] and [:alnum:] the underscore
192character is removed. The triples in the table consist of the base map offset,
193second map offset or -1 if no second map, and a non-negative value for map
194addition or a negative value for map subtraction (if there are two maps). The
195absolute value of the third field has these meanings: 0 => no tweaking, 1 =>
196remove vertical space characters, 2 => remove underscore. */
197
198static const int posix_class_maps[] = {
199  cbit_word,  cbit_digit, -2,             /* alpha */
200  cbit_lower, -1,          0,             /* lower */
201  cbit_upper, -1,          0,             /* upper */
202  cbit_word,  -1,          2,             /* alnum - word without underscore */
203  cbit_print, cbit_cntrl,  0,             /* ascii */
204  cbit_space, -1,          1,             /* blank - a GNU extension */
205  cbit_cntrl, -1,          0,             /* cntrl */
206  cbit_digit, -1,          0,             /* digit */
207  cbit_graph, -1,          0,             /* graph */
208  cbit_print, -1,          0,             /* print */
209  cbit_punct, -1,          0,             /* punct */
210  cbit_space, -1,          0,             /* space */
211  cbit_word,  -1,          0,             /* word - a Perl extension */
212  cbit_xdigit,-1,          0              /* xdigit */
213};
214
215
216#define STRING(a)  # a
217#define XSTRING(s) STRING(s)
218
219/* The texts of compile-time error messages. These are "char *" because they
220are passed to the outside world. Do not ever re-use any error number, because
221they are documented. Always add a new error instead. Messages marked DEAD below
222are no longer used. This used to be a table of strings, but in order to reduce
223the number of relocations needed when a shared library is loaded dynamically,
224it is now one long string. We cannot use a table of offsets, because the
225lengths of inserts such as XSTRING(MAX_NAME_SIZE) are not known. Instead, we
226simply count through to the one we want - this isn't a performance issue
227because these strings are used only when there is a compilation error. */
228
229static const char error_texts[] =
230  "no error\0"
231  "\\ at end of pattern\0"
232  "\\c at end of pattern\0"
233  "unrecognized character follows \\\0"
234  "numbers out of order in {} quantifier\0"
235  /* 5 */
236  "number too big in {} quantifier\0"
237  "missing terminating ] for character class\0"
238  "invalid escape sequence in character class\0"
239  "range out of order in character class\0"
240  "nothing to repeat\0"
241  /* 10 */
242  "operand of unlimited repeat could match the empty string\0"  /** DEAD **/
243  "internal error: unexpected repeat\0"
244  "unrecognized character after (? or (?-\0"
245  "POSIX named classes are supported only within a class\0"
246  "missing )\0"
247  /* 15 */
248  "reference to non-existent subpattern\0"
249  "erroffset passed as NULL\0"
250  "unknown option bit(s) set\0"
251  "missing ) after comment\0"
252  "parentheses nested too deeply\0"  /** DEAD **/
253  /* 20 */
254  "regular expression is too large\0"
255  "failed to get memory\0"
256  "unmatched parentheses\0"
257  "internal error: code overflow\0"
258  "unrecognized character after (?<\0"
259  /* 25 */
260  "lookbehind assertion is not fixed length\0"
261  "malformed number or name after (?(\0"
262  "conditional group contains more than two branches\0"
263  "assertion expected after (?(\0"
264  "(?R or (?[+-]digits must be followed by )\0"
265  /* 30 */
266  "unknown POSIX class name\0"
267  "POSIX collating elements are not supported\0"
268  "this version of PCRE is not compiled with PCRE_UTF8 support\0"
269  "spare error\0"  /** DEAD **/
270  "character value in \\x{...} sequence is too large\0"
271  /* 35 */
272  "invalid condition (?(0)\0"
273  "\\C not allowed in lookbehind assertion\0"
274  "PCRE does not support \\L, \\l, \\N, \\U, or \\u\0"
275  "number after (?C is > 255\0"
276  "closing ) for (?C expected\0"
277  /* 40 */
278  "recursive call could loop indefinitely\0"
279  "unrecognized character after (?P\0"
280  "syntax error in subpattern name (missing terminator)\0"
281  "two named subpatterns have the same name\0"
282  "invalid UTF-8 string\0"
283  /* 45 */
284  "support for \\P, \\p, and \\X has not been compiled\0"
285  "malformed \\P or \\p sequence\0"
286  "unknown property name after \\P or \\p\0"
287  "subpattern name is too long (maximum " XSTRING(MAX_NAME_SIZE) " characters)\0"
288  "too many named subpatterns (maximum " XSTRING(MAX_NAME_COUNT) ")\0"
289  /* 50 */
290  "repeated subpattern is too long\0"    /** DEAD **/
291  "octal value is greater than \\377 (not in UTF-8 mode)\0"
292  "internal error: overran compiling workspace\0"
293  "internal error: previously-checked referenced subpattern not found\0"
294  "DEFINE group contains more than one branch\0"
295  /* 55 */
296  "repeating a DEFINE group is not allowed\0"
297  "inconsistent NEWLINE options\0"
298  "\\g is not followed by a braced, angle-bracketed, or quoted name/number or by a plain number\0"
299  "a numbered reference must not be zero\0"
300  "(*VERB) with an argument is not supported\0"
301  /* 60 */
302  "(*VERB) not recognized\0"
303  "number is too big\0"
304  "subpattern name expected\0"
305  "digit expected after (?+\0"
306  "] is an invalid data character in JavaScript compatibility mode";
307
308
309/* Table to identify digits and hex digits. This is used when compiling
310patterns. Note that the tables in chartables are dependent on the locale, and
311may mark arbitrary characters as digits - but the PCRE compiling code expects
312to handle only 0-9, a-z, and A-Z as digits when compiling. That is why we have
313a private table here. It costs 256 bytes, but it is a lot faster than doing
314character value tests (at least in some simple cases I timed), and in some
315applications one wants PCRE to compile efficiently as well as match
316efficiently.
317
318For convenience, we use the same bit definitions as in chartables:
319
320  0x04   decimal digit
321  0x08   hexadecimal digit
322
323Then we can use ctype_digit and ctype_xdigit in the code. */
324
325#ifndef EBCDIC  /* This is the "normal" case, for ASCII systems */
326static const unsigned char digitab[] =
327  {
328  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   0-  7 */
329  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   8- 15 */
330  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  16- 23 */
331  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  24- 31 */
332  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*    - '  */
333  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  ( - /  */
334  0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c, /*  0 - 7  */
335  0x0c,0x0c,0x00,0x00,0x00,0x00,0x00,0x00, /*  8 - ?  */
336  0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /*  @ - G  */
337  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  H - O  */
338  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  P - W  */
339  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  X - _  */
340  0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /*  ` - g  */
341  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  h - o  */
342  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  p - w  */
343  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  x -127 */
344  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 128-135 */
345  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 136-143 */
346  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 144-151 */
347  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 152-159 */
348  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 160-167 */
349  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 168-175 */
350  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 176-183 */
351  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 184-191 */
352  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 192-199 */
353  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 200-207 */
354  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 208-215 */
355  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 216-223 */
356  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 224-231 */
357  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 232-239 */
358  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 240-247 */
359  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};/* 248-255 */
360
361#else           /* This is the "abnormal" case, for EBCDIC systems */
362static const unsigned char digitab[] =
363  {
364  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   0-  7  0 */
365  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   8- 15    */
366  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  16- 23 10 */
367  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  24- 31    */
368  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  32- 39 20 */
369  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  40- 47    */
370  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  48- 55 30 */
371  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  56- 63    */
372  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*    - 71 40 */
373  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  72- |     */
374  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  & - 87 50 */
375  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  88- 95    */
376  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  - -103 60 */
377  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 104- ?     */
378  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 112-119 70 */
379  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 120- "     */
380  0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /* 128- g  80 */
381  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  h -143    */
382  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 144- p  90 */
383  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  q -159    */
384  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 160- x  A0 */
385  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  y -175    */
386  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  ^ -183 B0 */
387  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 184-191    */
388  0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /*  { - G  C0 */
389  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  H -207    */
390  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  } - P  D0 */
391  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  Q -223    */
392  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  \ - X  E0 */
393  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  Y -239    */
394  0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c, /*  0 - 7  F0 */
395  0x0c,0x0c,0x00,0x00,0x00,0x00,0x00,0x00};/*  8 -255    */
396
397static const unsigned char ebcdic_chartab[] = { /* chartable partial dup */
398  0x80,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /*   0-  7 */
399  0x00,0x00,0x00,0x00,0x01,0x01,0x00,0x00, /*   8- 15 */
400  0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /*  16- 23 */
401  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  24- 31 */
402  0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /*  32- 39 */
403  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  40- 47 */
404  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  48- 55 */
405  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  56- 63 */
406  0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*    - 71 */
407  0x00,0x00,0x00,0x80,0x00,0x80,0x80,0x80, /*  72- |  */
408  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  & - 87 */
409  0x00,0x00,0x00,0x80,0x80,0x80,0x00,0x00, /*  88- 95 */
410  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  - -103 */
411  0x00,0x00,0x00,0x00,0x00,0x10,0x00,0x80, /* 104- ?  */
412  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 112-119 */
413  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 120- "  */
414  0x00,0x1a,0x1a,0x1a,0x1a,0x1a,0x1a,0x12, /* 128- g  */
415  0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  h -143 */
416  0x00,0x12,0x12,0x12,0x12,0x12,0x12,0x12, /* 144- p  */
417  0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  q -159 */
418  0x00,0x00,0x12,0x12,0x12,0x12,0x12,0x12, /* 160- x  */
419  0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  y -175 */
420  0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  ^ -183 */
421  0x00,0x00,0x80,0x00,0x00,0x00,0x00,0x00, /* 184-191 */
422  0x80,0x1a,0x1a,0x1a,0x1a,0x1a,0x1a,0x12, /*  { - G  */
423  0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  H -207 */
424  0x00,0x12,0x12,0x12,0x12,0x12,0x12,0x12, /*  } - P  */
425  0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  Q -223 */
426  0x00,0x00,0x12,0x12,0x12,0x12,0x12,0x12, /*  \ - X  */
427  0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  Y -239 */
428  0x1c,0x1c,0x1c,0x1c,0x1c,0x1c,0x1c,0x1c, /*  0 - 7  */
429  0x1c,0x1c,0x00,0x00,0x00,0x00,0x00,0x00};/*  8 -255 */
430#endif
431
432
433/* Definition to allow mutual recursion */
434
435static BOOL
436  compile_regex(int, int, uschar **, const uschar **, int *, BOOL, BOOL, int,
437    int *, int *, branch_chain *, compile_data *, int *);
438
439
440
441/*************************************************
442*            Find an error text                  *
443*************************************************/
444
445/* The error texts are now all in one long string, to save on relocations. As
446some of the text is of unknown length, we can't use a table of offsets.
447Instead, just count through the strings. This is not a performance issue
448because it happens only when there has been a compilation error.
449
450Argument:   the error number
451Returns:    pointer to the error string
452*/
453
454static const char *
455find_error_text(int n)
456{
457const char *s = error_texts;
458for (; n > 0; n--) while (*s++ != 0) {};
459return s;
460}
461
462
463/*************************************************
464*            Handle escapes                      *
465*************************************************/
466
467/* This function is called when a \ has been encountered. It either returns a
468positive value for a simple escape such as \n, or a negative value which
469encodes one of the more complicated things such as \d. A backreference to group
470n is returned as -(ESC_REF + n); ESC_REF is the highest ESC_xxx macro. When
471UTF-8 is enabled, a positive value greater than 255 may be returned. On entry,
472ptr is pointing at the \. On exit, it is on the final character of the escape
473sequence.
474
475Arguments:
476  ptrptr         points to the pattern position pointer
477  errorcodeptr   points to the errorcode variable
478  bracount       number of previous extracting brackets
479  options        the options bits
480  isclass        TRUE if inside a character class
481
482Returns:         zero or positive => a data character
483                 negative => a special escape sequence
484                 on error, errorcodeptr is set
485*/
486
487static int
488check_escape(const uschar **ptrptr, int *errorcodeptr, int bracount,
489  int options, BOOL isclass)
490{
491BOOL utf8 = (options & PCRE_UTF8) != 0;
492const uschar *ptr = *ptrptr + 1;
493int c, i;
494
495GETCHARINCTEST(c, ptr);           /* Get character value, increment pointer */
496ptr--;                            /* Set pointer back to the last byte */
497
498/* If backslash is at the end of the pattern, it's an error. */
499
500if (c == 0) *errorcodeptr = ERR1;
501
502/* Non-alphanumerics are literals. For digits or letters, do an initial lookup
503in a table. A non-zero result is something that can be returned immediately.
504Otherwise further processing may be required. */
505
506#ifndef EBCDIC  /* ASCII coding */
507else if (c < '0' || c > 'z') {}                           /* Not alphanumeric */
508else if ((i = escapes[c - '0']) != 0) c = i;
509
510#else           /* EBCDIC coding */
511else if (c < 'a' || (ebcdic_chartab[c] & 0x0E) == 0) {}   /* Not alphanumeric */
512else if ((i = escapes[c - 0x48]) != 0)  c = i;
513#endif
514
515/* Escapes that need further processing, or are illegal. */
516
517else
518  {
519  const uschar *oldptr;
520  BOOL braced, negated;
521
522  switch (c)
523    {
524    /* A number of Perl escapes are not handled by PCRE. We give an explicit
525    error. */
526
527    case 'l':
528    case 'L':
529    case 'N':
530    case 'u':
531    case 'U':
532    *errorcodeptr = ERR37;
533    break;
534
535    /* \g must be followed by one of a number of specific things:
536
537    (1) A number, either plain or braced. If positive, it is an absolute
538    backreference. If negative, it is a relative backreference. This is a Perl
539    5.10 feature.
540
541    (2) Perl 5.10 also supports \g{name} as a reference to a named group. This
542    is part of Perl's movement towards a unified syntax for back references. As
543    this is synonymous with \k{name}, we fudge it up by pretending it really
544    was \k.
545
546    (3) For Oniguruma compatibility we also support \g followed by a name or a
547    number either in angle brackets or in single quotes. However, these are
548    (possibly recursive) subroutine calls, _not_ backreferences. Just return
549    the -ESC_g code (cf \k). */
550
551    case 'g':
552    if (ptr[1] == '<' || ptr[1] == '\'')
553      {
554      c = -ESC_g;
555      break;
556      }
557
558    /* Handle the Perl-compatible cases */
559
560    if (ptr[1] == '{')
561      {
562      const uschar *p;
563      for (p = ptr+2; *p != 0 && *p != '}'; p++)
564        if (*p != '-' && (digitab[*p] & ctype_digit) == 0) break;
565      if (*p != 0 && *p != '}')
566        {
567        c = -ESC_k;
568        break;
569        }
570      braced = TRUE;
571      ptr++;
572      }
573    else braced = FALSE;
574
575    if (ptr[1] == '-')
576      {
577      negated = TRUE;
578      ptr++;
579      }
580    else negated = FALSE;
581
582    c = 0;
583    while ((digitab[ptr[1]] & ctype_digit) != 0)
584      c = c * 10 + *(++ptr) - '0';
585
586    if (c < 0)   /* Integer overflow */
587      {
588      *errorcodeptr = ERR61;
589      break;
590      }
591
592    if (braced && *(++ptr) != '}')
593      {
594      *errorcodeptr = ERR57;
595      break;
596      }
597
598    if (c == 0)
599      {
600      *errorcodeptr = ERR58;
601      break;
602      }
603
604    if (negated)
605      {
606      if (c > bracount)
607        {
608        *errorcodeptr = ERR15;
609        break;
610        }
611      c = bracount - (c - 1);
612      }
613
614    c = -(ESC_REF + c);
615    break;
616
617    /* The handling of escape sequences consisting of a string of digits
618    starting with one that is not zero is not straightforward. By experiment,
619    the way Perl works seems to be as follows:
620
621    Outside a character class, the digits are read as a decimal number. If the
622    number is less than 10, or if there are that many previous extracting
623    left brackets, then it is a back reference. Otherwise, up to three octal
624    digits are read to form an escaped byte. Thus \123 is likely to be octal
625    123 (cf \0123, which is octal 012 followed by the literal 3). If the octal
626    value is greater than 377, the least significant 8 bits are taken. Inside a
627    character class, \ followed by a digit is always an octal number. */
628
629    case '1': case '2': case '3': case '4': case '5':
630    case '6': case '7': case '8': case '9':
631
632    if (!isclass)
633      {
634      oldptr = ptr;
635      c -= '0';
636      while ((digitab[ptr[1]] & ctype_digit) != 0)
637        c = c * 10 + *(++ptr) - '0';
638      if (c < 0)    /* Integer overflow */
639        {
640        *errorcodeptr = ERR61;
641        break;
642        }
643      if (c < 10 || c <= bracount)
644        {
645        c = -(ESC_REF + c);
646        break;
647        }
648      ptr = oldptr;      /* Put the pointer back and fall through */
649      }
650
651    /* Handle an octal number following \. If the first digit is 8 or 9, Perl
652    generates a binary zero byte and treats the digit as a following literal.
653    Thus we have to pull back the pointer by one. */
654
655    if ((c = *ptr) >= '8')
656      {
657      ptr--;
658      c = 0;
659      break;
660      }
661
662    /* \0 always starts an octal number, but we may drop through to here with a
663    larger first octal digit. The original code used just to take the least
664    significant 8 bits of octal numbers (I think this is what early Perls used
665    to do). Nowadays we allow for larger numbers in UTF-8 mode, but no more
666    than 3 octal digits. */
667
668    case '0':
669    c -= '0';
670    while(i++ < 2 && ptr[1] >= '0' && ptr[1] <= '7')
671        c = c * 8 + *(++ptr) - '0';
672    if (!utf8 && c > 255) *errorcodeptr = ERR51;
673    break;
674
675    /* \x is complicated. \x{ddd} is a character number which can be greater
676    than 0xff in utf8 mode, but only if the ddd are hex digits. If not, { is
677    treated as a data character. */
678
679    case 'x':
680    if (ptr[1] == '{')
681      {
682      const uschar *pt = ptr + 2;
683      int count = 0;
684
685      c = 0;
686      while ((digitab[*pt] & ctype_xdigit) != 0)
687        {
688        register int cc = *pt++;
689        if (c == 0 && cc == '0') continue;     /* Leading zeroes */
690        count++;
691
692#ifndef EBCDIC  /* ASCII coding */
693        if (cc >= 'a') cc -= 32;               /* Convert to upper case */
694        c = (c << 4) + cc - ((cc < 'A')? '0' : ('A' - 10));
695#else           /* EBCDIC coding */
696        if (cc >= 'a' && cc <= 'z') cc += 64;  /* Convert to upper case */
697        c = (c << 4) + cc - ((cc >= '0')? '0' : ('A' - 10));
698#endif
699        }
700
701      if (*pt == '}')
702        {
703        if (c < 0 || count > (utf8? 8 : 2)) *errorcodeptr = ERR34;
704        ptr = pt;
705        break;
706        }
707
708      /* If the sequence of hex digits does not end with '}', then we don't
709      recognize this construct; fall through to the normal \x handling. */
710      }
711
712    /* Read just a single-byte hex-defined char */
713
714    c = 0;
715    while (i++ < 2 && (digitab[ptr[1]] & ctype_xdigit) != 0)
716      {
717      int cc;                               /* Some compilers don't like ++ */
718      cc = *(++ptr);                        /* in initializers */
719#ifndef EBCDIC  /* ASCII coding */
720      if (cc >= 'a') cc -= 32;              /* Convert to upper case */
721      c = c * 16 + cc - ((cc < 'A')? '0' : ('A' - 10));
722#else           /* EBCDIC coding */
723      if (cc <= 'z') cc += 64;              /* Convert to upper case */
724      c = c * 16 + cc - ((cc >= '0')? '0' : ('A' - 10));
725#endif
726      }
727    break;
728
729    /* For \c, a following letter is upper-cased; then the 0x40 bit is flipped.
730    This coding is ASCII-specific, but then the whole concept of \cx is
731    ASCII-specific. (However, an EBCDIC equivalent has now been added.) */
732
733    case 'c':
734    c = *(++ptr);
735    if (c == 0)
736      {
737      *errorcodeptr = ERR2;
738      break;
739      }
740
741#ifndef EBCDIC  /* ASCII coding */
742    if (c >= 'a' && c <= 'z') c -= 32;
743    c ^= 0x40;
744#else           /* EBCDIC coding */
745    if (c >= 'a' && c <= 'z') c += 64;
746    c ^= 0xC0;
747#endif
748    break;
749
750    /* PCRE_EXTRA enables extensions to Perl in the matter of escapes. Any
751    other alphanumeric following \ is an error if PCRE_EXTRA was set;
752    otherwise, for Perl compatibility, it is a literal. This code looks a bit
753    odd, but there used to be some cases other than the default, and there may
754    be again in future, so I haven't "optimized" it. */
755
756    default:
757    if ((options & PCRE_EXTRA) != 0) switch(c)
758      {
759      default:
760      *errorcodeptr = ERR3;
761      break;
762      }
763    break;
764    }
765  }
766
767*ptrptr = ptr;
768return c;
769}
770
771
772
773#ifdef SUPPORT_UCP
774/*************************************************
775*               Handle \P and \p                 *
776*************************************************/
777
778/* This function is called after \P or \p has been encountered, provided that
779PCRE is compiled with support for Unicode properties. On entry, ptrptr is
780pointing at the P or p. On exit, it is pointing at the final character of the
781escape sequence.
782
783Argument:
784  ptrptr         points to the pattern position pointer
785  negptr         points to a boolean that is set TRUE for negation else FALSE
786  dptr           points to an int that is set to the detailed property value
787  errorcodeptr   points to the error code variable
788
789Returns:         type value from ucp_type_table, or -1 for an invalid type
790*/
791
792static int
793get_ucp(const uschar **ptrptr, BOOL *negptr, int *dptr, int *errorcodeptr)
794{
795int c, i, bot, top;
796const uschar *ptr = *ptrptr;
797char name[32];
798
799c = *(++ptr);
800if (c == 0) goto ERROR_RETURN;
801
802*negptr = FALSE;
803
804/* \P or \p can be followed by a name in {}, optionally preceded by ^ for
805negation. */
806
807if (c == '{')
808  {
809  if (ptr[1] == '^')
810    {
811    *negptr = TRUE;
812    ptr++;
813    }
814  for (i = 0; i < (int)sizeof(name) - 1; i++)
815    {
816    c = *(++ptr);
817    if (c == 0) goto ERROR_RETURN;
818    if (c == '}') break;
819    name[i] = c;
820    }
821  if (c !='}') goto ERROR_RETURN;
822  name[i] = 0;
823  }
824
825/* Otherwise there is just one following character */
826
827else
828  {
829  name[0] = c;
830  name[1] = 0;
831  }
832
833*ptrptr = ptr;
834
835/* Search for a recognized property name using binary chop */
836
837bot = 0;
838top = _pcre_utt_size;
839
840while (bot < top)
841  {
842  i = (bot + top) >> 1;
843  c = strcmp(name, _pcre_utt_names + _pcre_utt[i].name_offset);
844  if (c == 0)
845    {
846    *dptr = _pcre_utt[i].value;
847    return _pcre_utt[i].type;
848    }
849  if (c > 0) bot = i + 1; else top = i;
850  }
851
852*errorcodeptr = ERR47;
853*ptrptr = ptr;
854return -1;
855
856ERROR_RETURN:
857*errorcodeptr = ERR46;
858*ptrptr = ptr;
859return -1;
860}
861#endif
862
863
864
865
866/*************************************************
867*            Check for counted repeat            *
868*************************************************/
869
870/* This function is called when a '{' is encountered in a place where it might
871start a quantifier. It looks ahead to see if it really is a quantifier or not.
872It is only a quantifier if it is one of the forms {ddd} {ddd,} or {ddd,ddd}
873where the ddds are digits.
874
875Arguments:
876  p         pointer to the first char after '{'
877
878Returns:    TRUE or FALSE
879*/
880
881static BOOL
882is_counted_repeat(const uschar *p)
883{
884if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
885while ((digitab[*p] & ctype_digit) != 0) p++;
886if (*p == '}') return TRUE;
887
888if (*p++ != ',') return FALSE;
889if (*p == '}') return TRUE;
890
891if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
892while ((digitab[*p] & ctype_digit) != 0) p++;
893
894return (*p == '}');
895}
896
897
898
899/*************************************************
900*         Read repeat counts                     *
901*************************************************/
902
903/* Read an item of the form {n,m} and return the values. This is called only
904after is_counted_repeat() has confirmed that a repeat-count quantifier exists,
905so the syntax is guaranteed to be correct, but we need to check the values.
906
907Arguments:
908  p              pointer to first char after '{'
909  minp           pointer to int for min
910  maxp           pointer to int for max
911                 returned as -1 if no max
912  errorcodeptr   points to error code variable
913
914Returns:         pointer to '}' on success;
915                 current ptr on error, with errorcodeptr set non-zero
916*/
917
918static const uschar *
919read_repeat_counts(const uschar *p, int *minp, int *maxp, int *errorcodeptr)
920{
921int min = 0;
922int max = -1;
923
924/* Read the minimum value and do a paranoid check: a negative value indicates
925an integer overflow. */
926
927while ((digitab[*p] & ctype_digit) != 0) min = min * 10 + *p++ - '0';
928if (min < 0 || min > 65535)
929  {
930  *errorcodeptr = ERR5;
931  return p;
932  }
933
934/* Read the maximum value if there is one, and again do a paranoid on its size.
935Also, max must not be less than min. */
936
937if (*p == '}') max = min; else
938  {
939  if (*(++p) != '}')
940    {
941    max = 0;
942    while((digitab[*p] & ctype_digit) != 0) max = max * 10 + *p++ - '0';
943    if (max < 0 || max > 65535)
944      {
945      *errorcodeptr = ERR5;
946      return p;
947      }
948    if (max < min)
949      {
950      *errorcodeptr = ERR4;
951      return p;
952      }
953    }
954  }
955
956/* Fill in the required variables, and pass back the pointer to the terminating
957'}'. */
958
959*minp = min;
960*maxp = max;
961return p;
962}
963
964
965
966/*************************************************
967*       Find forward referenced subpattern       *
968*************************************************/
969
970/* This function scans along a pattern's text looking for capturing
971subpatterns, and counting them. If it finds a named pattern that matches the
972name it is given, it returns its number. Alternatively, if the name is NULL, it
973returns when it reaches a given numbered subpattern. This is used for forward
974references to subpatterns. We know that if (?P< is encountered, the name will
975be terminated by '>' because that is checked in the first pass.
976
977Arguments:
978  ptr          current position in the pattern
979  cd           compile background data
980  name         name to seek, or NULL if seeking a numbered subpattern
981  lorn         name length, or subpattern number if name is NULL
982  xmode        TRUE if we are in /x mode
983
984Returns:       the number of the named subpattern, or -1 if not found
985*/
986
987static int
988find_parens(const uschar *ptr, compile_data *cd, const uschar *name, int lorn,
989  BOOL xmode)
990{
991const uschar *thisname;
992int count = cd->bracount;
993
994for (; *ptr != 0; ptr++)
995  {
996  int term;
997
998  /* Skip over backslashed characters and also entire \Q...\E */
999
1000  if (*ptr == '\\')
1001    {
1002    if (*(++ptr) == 0) return -1;
1003    if (*ptr == 'Q') for (;;)
1004      {
1005      while (*(++ptr) != 0 && *ptr != '\\') {};
1006      if (*ptr == 0) return -1;
1007      if (*(++ptr) == 'E') break;
1008      }
1009    continue;
1010    }
1011
1012  /* Skip over character classes; this logic must be similar to the way they
1013  are handled for real. If the first character is '^', skip it. Also, if the
1014  first few characters (either before or after ^) are \Q\E or \E we skip them
1015  too. This makes for compatibility with Perl. */
1016
1017  if (*ptr == '[')
1018    {
1019    BOOL negate_class = FALSE;
1020    for (;;)
1021      {
1022      int c = *(++ptr);
1023      if (c == '\\')
1024        {
1025        if (ptr[1] == 'E') ptr++;
1026          else if (strncmp((const char *)ptr+1, "Q\\E", 3) == 0) ptr += 3;
1027            else break;
1028        }
1029      else if (!negate_class && c == '^')
1030        negate_class = TRUE;
1031      else break;
1032      }
1033
1034    /* If the next character is ']', it is a data character that must be
1035    skipped, except in JavaScript compatibility mode. */
1036
1037    if (ptr[1] == ']' && (cd->external_options & PCRE_JAVASCRIPT_COMPAT) == 0)
1038      ptr++;
1039
1040    while (*(++ptr) != ']')
1041      {
1042      if (*ptr == 0) return -1;
1043      if (*ptr == '\\')
1044        {
1045        if (*(++ptr) == 0) return -1;
1046        if (*ptr == 'Q') for (;;)
1047          {
1048          while (*(++ptr) != 0 && *ptr != '\\') {};
1049          if (*ptr == 0) return -1;
1050          if (*(++ptr) == 'E') break;
1051          }
1052        continue;
1053        }
1054      }
1055    continue;
1056    }
1057
1058  /* Skip comments in /x mode */
1059
1060  if (xmode && *ptr == '#')
1061    {
1062    while (*(++ptr) != 0 && *ptr != '\n') {};
1063    if (*ptr == 0) return -1;
1064    continue;
1065    }
1066
1067  /* An opening parens must now be a real metacharacter */
1068
1069  if (*ptr != '(') continue;
1070  if (ptr[1] != '?' && ptr[1] != '*')
1071    {
1072    count++;
1073    if (name == NULL && count == lorn) return count;
1074    continue;
1075    }
1076
1077  ptr += 2;
1078  if (*ptr == 'P') ptr++;                      /* Allow optional P */
1079
1080  /* We have to disambiguate (?<! and (?<= from (?<name> */
1081
1082  if ((*ptr != '<' || ptr[1] == '!' || ptr[1] == '=') &&
1083       *ptr != '\'')
1084    continue;
1085
1086  count++;
1087
1088  if (name == NULL && count == lorn) return count;
1089  term = *ptr++;
1090  if (term == '<') term = '>';
1091  thisname = ptr;
1092  while (*ptr != term) ptr++;
1093  if (name != NULL && lorn == ptr - thisname &&
1094      strncmp((const char *)name, (const char *)thisname, lorn) == 0)
1095    return count;
1096  }
1097
1098return -1;
1099}
1100
1101
1102
1103/*************************************************
1104*      Find first significant op code            *
1105*************************************************/
1106
1107/* This is called by several functions that scan a compiled expression looking
1108for a fixed first character, or an anchoring op code etc. It skips over things
1109that do not influence this. For some calls, a change of option is important.
1110For some calls, it makes sense to skip negative forward and all backward
1111assertions, and also the \b assertion; for others it does not.
1112
1113Arguments:
1114  code         pointer to the start of the group
1115  options      pointer to external options
1116  optbit       the option bit whose changing is significant, or
1117                 zero if none are
1118  skipassert   TRUE if certain assertions are to be skipped
1119
1120Returns:       pointer to the first significant opcode
1121*/
1122
1123static const uschar*
1124first_significant_code(const uschar *code, int *options, int optbit,
1125  BOOL skipassert)
1126{
1127for (;;)
1128  {
1129  switch ((int)*code)
1130    {
1131    case OP_OPT:
1132    if (optbit > 0 && ((int)code[1] & optbit) != (*options & optbit))
1133      *options = (int)code[1];
1134    code += 2;
1135    break;
1136
1137    case OP_ASSERT_NOT:
1138    case OP_ASSERTBACK:
1139    case OP_ASSERTBACK_NOT:
1140    if (!skipassert) return code;
1141    do code += GET(code, 1); while (*code == OP_ALT);
1142    code += _pcre_OP_lengths[*code];
1143    break;
1144
1145    case OP_WORD_BOUNDARY:
1146    case OP_NOT_WORD_BOUNDARY:
1147    if (!skipassert) return code;
1148    /* Fall through */
1149
1150    case OP_CALLOUT:
1151    case OP_CREF:
1152    case OP_RREF:
1153    case OP_DEF:
1154    code += _pcre_OP_lengths[*code];
1155    break;
1156
1157    default:
1158    return code;
1159    }
1160  }
1161/* Control never reaches here */
1162}
1163
1164
1165
1166
1167/*************************************************
1168*        Find the fixed length of a pattern      *
1169*************************************************/
1170
1171/* Scan a pattern and compute the fixed length of subject that will match it,
1172if the length is fixed. This is needed for dealing with backward assertions.
1173In UTF8 mode, the result is in characters rather than bytes.
1174
1175Arguments:
1176  code     points to the start of the pattern (the bracket)
1177  options  the compiling options
1178
1179Returns:   the fixed length, or -1 if there is no fixed length,
1180             or -2 if \C was encountered
1181*/
1182
1183static int
1184find_fixedlength(uschar *code, int options)
1185{
1186int length = -1;
1187
1188register int branchlength = 0;
1189register uschar *cc = code + 1 + LINK_SIZE;
1190
1191/* Scan along the opcodes for this branch. If we get to the end of the
1192branch, check the length against that of the other branches. */
1193
1194for (;;)
1195  {
1196  int d;
1197  register int op = *cc;
1198  switch (op)
1199    {
1200    case OP_CBRA:
1201    case OP_BRA:
1202    case OP_ONCE:
1203    case OP_COND:
1204    d = find_fixedlength(cc + ((op == OP_CBRA)? 2:0), options);
1205    if (d < 0) return d;
1206    branchlength += d;
1207    do cc += GET(cc, 1); while (*cc == OP_ALT);
1208    cc += 1 + LINK_SIZE;
1209    break;
1210
1211    /* Reached end of a branch; if it's a ket it is the end of a nested
1212    call. If it's ALT it is an alternation in a nested call. If it is
1213    END it's the end of the outer call. All can be handled by the same code. */
1214
1215    case OP_ALT:
1216    case OP_KET:
1217    case OP_KETRMAX:
1218    case OP_KETRMIN:
1219    case OP_END:
1220    if (length < 0) length = branchlength;
1221      else if (length != branchlength) return -1;
1222    if (*cc != OP_ALT) return length;
1223    cc += 1 + LINK_SIZE;
1224    branchlength = 0;
1225    break;
1226
1227    /* Skip over assertive subpatterns */
1228
1229    case OP_ASSERT:
1230    case OP_ASSERT_NOT:
1231    case OP_ASSERTBACK:
1232    case OP_ASSERTBACK_NOT:
1233    do cc += GET(cc, 1); while (*cc == OP_ALT);
1234    /* Fall through */
1235
1236    /* Skip over things that don't match chars */
1237
1238    case OP_REVERSE:
1239    case OP_CREF:
1240    case OP_RREF:
1241    case OP_DEF:
1242    case OP_OPT:
1243    case OP_CALLOUT:
1244    case OP_SOD:
1245    case OP_SOM:
1246    case OP_EOD:
1247    case OP_EODN:
1248    case OP_CIRC:
1249    case OP_DOLL:
1250    case OP_NOT_WORD_BOUNDARY:
1251    case OP_WORD_BOUNDARY:
1252    cc += _pcre_OP_lengths[*cc];
1253    break;
1254
1255    /* Handle literal characters */
1256
1257    case OP_CHAR:
1258    case OP_CHARNC:
1259    case OP_NOT:
1260    branchlength++;
1261    cc += 2;
1262#ifdef SUPPORT_UTF8
1263    if ((options & PCRE_UTF8) != 0)
1264      {
1265      while ((*cc & 0xc0) == 0x80) cc++;
1266      }
1267#endif
1268    break;
1269
1270    /* Handle exact repetitions. The count is already in characters, but we
1271    need to skip over a multibyte character in UTF8 mode.  */
1272
1273    case OP_EXACT:
1274    branchlength += GET2(cc,1);
1275    cc += 4;
1276#ifdef SUPPORT_UTF8
1277    if ((options & PCRE_UTF8) != 0)
1278      {
1279      while((*cc & 0x80) == 0x80) cc++;
1280      }
1281#endif
1282    break;
1283
1284    case OP_TYPEEXACT:
1285    branchlength += GET2(cc,1);
1286    if (cc[3] == OP_PROP || cc[3] == OP_NOTPROP) cc += 2;
1287    cc += 4;
1288    break;
1289
1290    /* Handle single-char matchers */
1291
1292    case OP_PROP:
1293    case OP_NOTPROP:
1294    cc += 2;
1295    /* Fall through */
1296
1297    case OP_NOT_DIGIT:
1298    case OP_DIGIT:
1299    case OP_NOT_WHITESPACE:
1300    case OP_WHITESPACE:
1301    case OP_NOT_WORDCHAR:
1302    case OP_WORDCHAR:
1303    case OP_ANY:
1304    case OP_ALLANY:
1305    branchlength++;
1306    cc++;
1307    break;
1308
1309    /* The single-byte matcher isn't allowed */
1310
1311    case OP_ANYBYTE:
1312    return -2;
1313
1314    /* Check a class for variable quantification */
1315
1316#ifdef SUPPORT_UTF8
1317    case OP_XCLASS:
1318    cc += GET(cc, 1) - 33;
1319    /* Fall through */
1320#endif
1321
1322    case OP_CLASS:
1323    case OP_NCLASS:
1324    cc += 33;
1325
1326    switch (*cc)
1327      {
1328      case OP_CRSTAR:
1329      case OP_CRMINSTAR:
1330      case OP_CRQUERY:
1331      case OP_CRMINQUERY:
1332      return -1;
1333
1334      case OP_CRRANGE:
1335      case OP_CRMINRANGE:
1336      if (GET2(cc,1) != GET2(cc,3)) return -1;
1337      branchlength += GET2(cc,1);
1338      cc += 5;
1339      break;
1340
1341      default:
1342      branchlength++;
1343      }
1344    break;
1345
1346    /* Anything else is variable length */
1347
1348    default:
1349    return -1;
1350    }
1351  }
1352/* Control never gets here */
1353}
1354
1355
1356
1357
1358/*************************************************
1359*    Scan compiled regex for numbered bracket    *
1360*************************************************/
1361
1362/* This little function scans through a compiled pattern until it finds a
1363capturing bracket with the given number.
1364
1365Arguments:
1366  code        points to start of expression
1367  utf8        TRUE in UTF-8 mode
1368  number      the required bracket number
1369
1370Returns:      pointer to the opcode for the bracket, or NULL if not found
1371*/
1372
1373static const uschar *
1374find_bracket(const uschar *code, BOOL utf8, int number)
1375{
1376for (;;)
1377  {
1378  register int c = *code;
1379  if (c == OP_END) return NULL;
1380
1381  /* XCLASS is used for classes that cannot be represented just by a bit
1382  map. This includes negated single high-valued characters. The length in
1383  the table is zero; the actual length is stored in the compiled code. */
1384
1385  if (c == OP_XCLASS) code += GET(code, 1);
1386
1387  /* Handle capturing bracket */
1388
1389  else if (c == OP_CBRA)
1390    {
1391    int n = GET2(code, 1+LINK_SIZE);
1392    if (n == number) return (uschar *)code;
1393    code += _pcre_OP_lengths[c];
1394    }
1395
1396  /* Otherwise, we can get the item's length from the table, except that for
1397  repeated character types, we have to test for \p and \P, which have an extra
1398  two bytes of parameters. */
1399
1400  else
1401    {
1402    switch(c)
1403      {
1404      case OP_TYPESTAR:
1405      case OP_TYPEMINSTAR:
1406      case OP_TYPEPLUS:
1407      case OP_TYPEMINPLUS:
1408      case OP_TYPEQUERY:
1409      case OP_TYPEMINQUERY:
1410      case OP_TYPEPOSSTAR:
1411      case OP_TYPEPOSPLUS:
1412      case OP_TYPEPOSQUERY:
1413      if (code[1] == OP_PROP || code[1] == OP_NOTPROP) code += 2;
1414      break;
1415
1416      case OP_TYPEUPTO:
1417      case OP_TYPEMINUPTO:
1418      case OP_TYPEEXACT:
1419      case OP_TYPEPOSUPTO:
1420      if (code[3] == OP_PROP || code[3] == OP_NOTPROP) code += 2;
1421      break;
1422      }
1423
1424    /* Add in the fixed length from the table */
1425
1426    code += _pcre_OP_lengths[c];
1427
1428  /* In UTF-8 mode, opcodes that are followed by a character may be followed by
1429  a multi-byte character. The length in the table is a minimum, so we have to
1430  arrange to skip the extra bytes. */
1431
1432#ifdef SUPPORT_UTF8
1433    if (utf8) switch(c)
1434      {
1435      case OP_CHAR:
1436      case OP_CHARNC:
1437      case OP_EXACT:
1438      case OP_UPTO:
1439      case OP_MINUPTO:
1440      case OP_POSUPTO:
1441      case OP_STAR:
1442      case OP_MINSTAR:
1443      case OP_POSSTAR:
1444      case OP_PLUS:
1445      case OP_MINPLUS:
1446      case OP_POSPLUS:
1447      case OP_QUERY:
1448      case OP_MINQUERY:
1449      case OP_POSQUERY:
1450      if (code[-1] >= 0xc0) code += _pcre_utf8_table4[code[-1] & 0x3f];
1451      break;
1452      }
1453#else
1454    (void)(utf8);  /* Keep compiler happy by referencing function argument */
1455#endif
1456    }
1457  }
1458}
1459
1460
1461
1462/*************************************************
1463*   Scan compiled regex for recursion reference  *
1464*************************************************/
1465
1466/* This little function scans through a compiled pattern until it finds an
1467instance of OP_RECURSE.
1468
1469Arguments:
1470  code        points to start of expression
1471  utf8        TRUE in UTF-8 mode
1472
1473Returns:      pointer to the opcode for OP_RECURSE, or NULL if not found
1474*/
1475
1476static const uschar *
1477find_recurse(const uschar *code, BOOL utf8)
1478{
1479for (;;)
1480  {
1481  register int c = *code;
1482  if (c == OP_END) return NULL;
1483  if (c == OP_RECURSE) return code;
1484
1485  /* XCLASS is used for classes that cannot be represented just by a bit
1486  map. This includes negated single high-valued characters. The length in
1487  the table is zero; the actual length is stored in the compiled code. */
1488
1489  if (c == OP_XCLASS) code += GET(code, 1);
1490
1491  /* Otherwise, we can get the item's length from the table, except that for
1492  repeated character types, we have to test for \p and \P, which have an extra
1493  two bytes of parameters. */
1494
1495  else
1496    {
1497    switch(c)
1498      {
1499      case OP_TYPESTAR:
1500      case OP_TYPEMINSTAR:
1501      case OP_TYPEPLUS:
1502      case OP_TYPEMINPLUS:
1503      case OP_TYPEQUERY:
1504      case OP_TYPEMINQUERY:
1505      case OP_TYPEPOSSTAR:
1506      case OP_TYPEPOSPLUS:
1507      case OP_TYPEPOSQUERY:
1508      if (code[1] == OP_PROP || code[1] == OP_NOTPROP) code += 2;
1509      break;
1510
1511      case OP_TYPEPOSUPTO:
1512      case OP_TYPEUPTO:
1513      case OP_TYPEMINUPTO:
1514      case OP_TYPEEXACT:
1515      if (code[3] == OP_PROP || code[3] == OP_NOTPROP) code += 2;
1516      break;
1517      }
1518
1519    /* Add in the fixed length from the table */
1520
1521    code += _pcre_OP_lengths[c];
1522
1523    /* In UTF-8 mode, opcodes that are followed by a character may be followed
1524    by a multi-byte character. The length in the table is a minimum, so we have
1525    to arrange to skip the extra bytes. */
1526
1527#ifdef SUPPORT_UTF8
1528    if (utf8) switch(c)
1529      {
1530      case OP_CHAR:
1531      case OP_CHARNC:
1532      case OP_EXACT:
1533      case OP_UPTO:
1534      case OP_MINUPTO:
1535      case OP_POSUPTO:
1536      case OP_STAR:
1537      case OP_MINSTAR:
1538      case OP_POSSTAR:
1539      case OP_PLUS:
1540      case OP_MINPLUS:
1541      case OP_POSPLUS:
1542      case OP_QUERY:
1543      case OP_MINQUERY:
1544      case OP_POSQUERY:
1545      if (code[-1] >= 0xc0) code += _pcre_utf8_table4[code[-1] & 0x3f];
1546      break;
1547      }
1548#else
1549    (void)(utf8);  /* Keep compiler happy by referencing function argument */
1550#endif
1551    }
1552  }
1553}
1554
1555
1556
1557/*************************************************
1558*    Scan compiled branch for non-emptiness      *
1559*************************************************/
1560
1561/* This function scans through a branch of a compiled pattern to see whether it
1562can match the empty string or not. It is called from could_be_empty()
1563below and from compile_branch() when checking for an unlimited repeat of a
1564group that can match nothing. Note that first_significant_code() skips over
1565backward and negative forward assertions when its final argument is TRUE. If we
1566hit an unclosed bracket, we return "empty" - this means we've struck an inner
1567bracket whose current branch will already have been scanned.
1568
1569Arguments:
1570  code        points to start of search
1571  endcode     points to where to stop
1572  utf8        TRUE if in UTF8 mode
1573
1574Returns:      TRUE if what is matched could be empty
1575*/
1576
1577static BOOL
1578could_be_empty_branch(const uschar *code, const uschar *endcode, BOOL utf8)
1579{
1580register int c;
1581for (code = first_significant_code(code + _pcre_OP_lengths[*code], NULL, 0, TRUE);
1582     code < endcode;
1583     code = first_significant_code(code + _pcre_OP_lengths[c], NULL, 0, TRUE))
1584  {
1585  const uschar *ccode;
1586
1587  c = *code;
1588
1589  /* Skip over forward assertions; the other assertions are skipped by
1590  first_significant_code() with a TRUE final argument. */
1591
1592  if (c == OP_ASSERT)
1593    {
1594    do code += GET(code, 1); while (*code == OP_ALT);
1595    c = *code;
1596    continue;
1597    }
1598
1599  /* Groups with zero repeats can of course be empty; skip them. */
1600
1601  if (c == OP_BRAZERO || c == OP_BRAMINZERO || c == OP_SKIPZERO)
1602    {
1603    code += _pcre_OP_lengths[c];
1604    do code += GET(code, 1); while (*code == OP_ALT);
1605    c = *code;
1606    continue;
1607    }
1608
1609  /* For other groups, scan the branches. */
1610
1611  if (c == OP_BRA || c == OP_CBRA || c == OP_ONCE || c == OP_COND)
1612    {
1613    BOOL empty_branch;
1614    if (GET(code, 1) == 0) return TRUE;    /* Hit unclosed bracket */
1615
1616    /* Scan a closed bracket */
1617
1618    empty_branch = FALSE;
1619    do
1620      {
1621      if (!empty_branch && could_be_empty_branch(code, endcode, utf8))
1622        empty_branch = TRUE;
1623      code += GET(code, 1);
1624      }
1625    while (*code == OP_ALT);
1626    if (!empty_branch) return FALSE;   /* All branches are non-empty */
1627    c = *code;
1628    continue;
1629    }
1630
1631  /* Handle the other opcodes */
1632
1633  switch (c)
1634    {
1635    /* Check for quantifiers after a class. XCLASS is used for classes that
1636    cannot be represented just by a bit map. This includes negated single
1637    high-valued characters. The length in _pcre_OP_lengths[] is zero; the
1638    actual length is stored in the compiled code, so we must update "code"
1639    here. */
1640
1641#ifdef SUPPORT_UTF8
1642    case OP_XCLASS:
1643    ccode = code += GET(code, 1);
1644    goto CHECK_CLASS_REPEAT;
1645#endif
1646
1647    case OP_CLASS:
1648    case OP_NCLASS:
1649    ccode = code + 33;
1650
1651#ifdef SUPPORT_UTF8
1652    CHECK_CLASS_REPEAT:
1653#endif
1654
1655    switch (*ccode)
1656      {
1657      case OP_CRSTAR:            /* These could be empty; continue */
1658      case OP_CRMINSTAR:
1659      case OP_CRQUERY:
1660      case OP_CRMINQUERY:
1661      break;
1662
1663      default:                   /* Non-repeat => class must match */
1664      case OP_CRPLUS:            /* These repeats aren't empty */
1665      case OP_CRMINPLUS:
1666      return FALSE;
1667
1668      case OP_CRRANGE:
1669      case OP_CRMINRANGE:
1670      if (GET2(ccode, 1) > 0) return FALSE;  /* Minimum > 0 */
1671      break;
1672      }
1673    break;
1674
1675    /* Opcodes that must match a character */
1676
1677    case OP_PROP:
1678    case OP_NOTPROP:
1679    case OP_EXTUNI:
1680    case OP_NOT_DIGIT:
1681    case OP_DIGIT:
1682    case OP_NOT_WHITESPACE:
1683    case OP_WHITESPACE:
1684    case OP_NOT_WORDCHAR:
1685    case OP_WORDCHAR:
1686    case OP_ANY:
1687    case OP_ALLANY:
1688    case OP_ANYBYTE:
1689    case OP_CHAR:
1690    case OP_CHARNC:
1691    case OP_NOT:
1692    case OP_PLUS:
1693    case OP_MINPLUS:
1694    case OP_POSPLUS:
1695    case OP_EXACT:
1696    case OP_NOTPLUS:
1697    case OP_NOTMINPLUS:
1698    case OP_NOTPOSPLUS:
1699    case OP_NOTEXACT:
1700    case OP_TYPEPLUS:
1701    case OP_TYPEMINPLUS:
1702    case OP_TYPEPOSPLUS:
1703    case OP_TYPEEXACT:
1704    return FALSE;
1705
1706    /* These are going to continue, as they may be empty, but we have to
1707    fudge the length for the \p and \P cases. */
1708
1709    case OP_TYPESTAR:
1710    case OP_TYPEMINSTAR:
1711    case OP_TYPEPOSSTAR:
1712    case OP_TYPEQUERY:
1713    case OP_TYPEMINQUERY:
1714    case OP_TYPEPOSQUERY:
1715    if (code[1] == OP_PROP || code[1] == OP_NOTPROP) code += 2;
1716    break;
1717
1718    /* Same for these */
1719
1720    case OP_TYPEUPTO:
1721    case OP_TYPEMINUPTO:
1722    case OP_TYPEPOSUPTO:
1723    if (code[3] == OP_PROP || code[3] == OP_NOTPROP) code += 2;
1724    break;
1725
1726    /* End of branch */
1727
1728    case OP_KET:
1729    case OP_KETRMAX:
1730    case OP_KETRMIN:
1731    case OP_ALT:
1732    return TRUE;
1733
1734    /* In UTF-8 mode, STAR, MINSTAR, POSSTAR, QUERY, MINQUERY, POSQUERY, UPTO,
1735    MINUPTO, and POSUPTO may be followed by a multibyte character */
1736
1737#ifdef SUPPORT_UTF8
1738    case OP_STAR:
1739    case OP_MINSTAR:
1740    case OP_POSSTAR:
1741    case OP_QUERY:
1742    case OP_MINQUERY:
1743    case OP_POSQUERY:
1744    case OP_UPTO:
1745    case OP_MINUPTO:
1746    case OP_POSUPTO:
1747    if (utf8) while ((code[2] & 0xc0) == 0x80) code++;
1748    break;
1749#endif
1750    }
1751  }
1752
1753return TRUE;
1754}
1755
1756
1757
1758/*************************************************
1759*    Scan compiled regex for non-emptiness       *
1760*************************************************/
1761
1762/* This function is called to check for left recursive calls. We want to check
1763the current branch of the current pattern to see if it could match the empty
1764string. If it could, we must look outwards for branches at other levels,
1765stopping when we pass beyond the bracket which is the subject of the recursion.
1766
1767Arguments:
1768  code        points to start of the recursion
1769  endcode     points to where to stop (current RECURSE item)
1770  bcptr       points to the chain of current (unclosed) branch starts
1771  utf8        TRUE if in UTF-8 mode
1772
1773Returns:      TRUE if what is matched could be empty
1774*/
1775
1776static BOOL
1777could_be_empty(const uschar *code, const uschar *endcode, branch_chain *bcptr,
1778  BOOL utf8)
1779{
1780while (bcptr != NULL && bcptr->current >= code)
1781  {
1782  if (!could_be_empty_branch(bcptr->current, endcode, utf8)) return FALSE;
1783  bcptr = bcptr->outer;
1784  }
1785return TRUE;
1786}
1787
1788
1789
1790/*************************************************
1791*           Check for POSIX class syntax         *
1792*************************************************/
1793
1794/* This function is called when the sequence "[:" or "[." or "[=" is
1795encountered in a character class. It checks whether this is followed by a
1796sequence of characters terminated by a matching ":]" or ".]" or "=]". If we
1797reach an unescaped ']' without the special preceding character, return FALSE.
1798
1799Originally, this function only recognized a sequence of letters between the
1800terminators, but it seems that Perl recognizes any sequence of characters,
1801though of course unknown POSIX names are subsequently rejected. Perl gives an
1802"Unknown POSIX class" error for [:f\oo:] for example, where previously PCRE
1803didn't consider this to be a POSIX class. Likewise for [:1234:].
1804
1805The problem in trying to be exactly like Perl is in the handling of escapes. We
1806have to be sure that [abc[:x\]pqr] is *not* treated as containing a POSIX
1807class, but [abc[:x\]pqr:]] is (so that an error can be generated). The code
1808below handles the special case of \], but does not try to do any other escape
1809processing. This makes it different from Perl for cases such as [:l\ower:]
1810where Perl recognizes it as the POSIX class "lower" but PCRE does not recognize
1811"l\ower". This is a lesser evil that not diagnosing bad classes when Perl does,
1812I think.
1813
1814Arguments:
1815  ptr      pointer to the initial [
1816  endptr   where to return the end pointer
1817
1818Returns:   TRUE or FALSE
1819*/
1820
1821static BOOL
1822check_posix_syntax(const uschar *ptr, const uschar **endptr)
1823{
1824int terminator;          /* Don't combine these lines; the Solaris cc */
1825terminator = *(++ptr);   /* compiler warns about "non-constant" initializer. */
1826for (++ptr; *ptr != 0; ptr++)
1827  {
1828  if (*ptr == '\\' && ptr[1] == ']') ptr++; else
1829    {
1830    if (*ptr == ']') return FALSE;
1831    if (*ptr == terminator && ptr[1] == ']')
1832      {
1833      *endptr = ptr;
1834      return TRUE;
1835      }
1836    }
1837  }
1838return FALSE;
1839}
1840
1841
1842
1843
1844/*************************************************
1845*          Check POSIX class name                *
1846*************************************************/
1847
1848/* This function is called to check the name given in a POSIX-style class entry
1849such as [:alnum:].
1850
1851Arguments:
1852  ptr        points to the first letter
1853  len        the length of the name
1854
1855Returns:     a value representing the name, or -1 if unknown
1856*/
1857
1858static int
1859check_posix_name(const uschar *ptr, int len)
1860{
1861const char *pn = posix_names;
1862register int yield = 0;
1863while (posix_name_lengths[yield] != 0)
1864  {
1865  if (len == posix_name_lengths[yield] &&
1866    strncmp((const char *)ptr, pn, len) == 0) return yield;
1867  pn += posix_name_lengths[yield] + 1;
1868  yield++;
1869  }
1870return -1;
1871}
1872
1873
1874/*************************************************
1875*    Adjust OP_RECURSE items in repeated group   *
1876*************************************************/
1877
1878/* OP_RECURSE items contain an offset from the start of the regex to the group
1879that is referenced. This means that groups can be replicated for fixed
1880repetition simply by copying (because the recursion is allowed to refer to
1881earlier groups that are outside the current group). However, when a group is
1882optional (i.e. the minimum quantifier is zero), OP_BRAZERO or OP_SKIPZERO is
1883inserted before it, after it has been compiled. This means that any OP_RECURSE
1884items within it that refer to the group itself or any contained groups have to
1885have their offsets adjusted. That one of the jobs of this function. Before it
1886is called, the partially compiled regex must be temporarily terminated with
1887OP_END.
1888
1889This function has been extended with the possibility of forward references for
1890recursions and subroutine calls. It must also check the list of such references
1891for the group we are dealing with. If it finds that one of the recursions in
1892the current group is on this list, it adjusts the offset in the list, not the
1893value in the reference (which is a group number).
1894
1895Arguments:
1896  group      points to the start of the group
1897  adjust     the amount by which the group is to be moved
1898  utf8       TRUE in UTF-8 mode
1899  cd         contains pointers to tables etc.
1900  save_hwm   the hwm forward reference pointer at the start of the group
1901
1902Returns:     nothing
1903*/
1904
1905static void
1906adjust_recurse(uschar *group, int adjust, BOOL utf8, compile_data *cd,
1907  uschar *save_hwm)
1908{
1909uschar *ptr = group;
1910
1911while ((ptr = (uschar *)find_recurse(ptr, utf8)) != NULL)
1912  {
1913  int offset;
1914  uschar *hc;
1915
1916  /* See if this recursion is on the forward reference list. If so, adjust the
1917  reference. */
1918
1919  for (hc = save_hwm; hc < cd->hwm; hc += LINK_SIZE)
1920    {
1921    offset = GET(hc, 0);
1922    if (cd->start_code + offset == ptr + 1)
1923      {
1924      PUT(hc, 0, offset + adjust);
1925      break;
1926      }
1927    }
1928
1929  /* Otherwise, adjust the recursion offset if it's after the start of this
1930  group. */
1931
1932  if (hc >= cd->hwm)
1933    {
1934    offset = GET(ptr, 1);
1935    if (cd->start_code + offset >= group) PUT(ptr, 1, offset + adjust);
1936    }
1937
1938  ptr += 1 + LINK_SIZE;
1939  }
1940}
1941
1942
1943
1944/*************************************************
1945*        Insert an automatic callout point       *
1946*************************************************/
1947
1948/* This function is called when the PCRE_AUTO_CALLOUT option is set, to insert
1949callout points before each pattern item.
1950
1951Arguments:
1952  code           current code pointer
1953  ptr            current pattern pointer
1954  cd             pointers to tables etc
1955
1956Returns:         new code pointer
1957*/
1958
1959static uschar *
1960auto_callout(uschar *code, const uschar *ptr, compile_data *cd)
1961{
1962*code++ = OP_CALLOUT;
1963*code++ = 255;
1964PUT(code, 0, ptr - cd->start_pattern);  /* Pattern offset */
1965PUT(code, LINK_SIZE, 0);                /* Default length */
1966return code + 2*LINK_SIZE;
1967}
1968
1969
1970
1971/*************************************************
1972*         Complete a callout item                *
1973*************************************************/
1974
1975/* A callout item contains the length of the next item in the pattern, which
1976we can't fill in till after we have reached the relevant point. This is used
1977for both automatic and manual callouts.
1978
1979Arguments:
1980  previous_callout   points to previous callout item
1981  ptr                current pattern pointer
1982  cd                 pointers to tables etc
1983
1984Returns:             nothing
1985*/
1986
1987static void
1988complete_callout(uschar *previous_callout, const uschar *ptr, compile_data *cd)
1989{
1990int length = ptr - cd->start_pattern - GET(previous_callout, 2);
1991PUT(previous_callout, 2 + LINK_SIZE, length);
1992}
1993
1994
1995
1996#ifdef SUPPORT_UCP
1997/*************************************************
1998*           Get othercase range                  *
1999*************************************************/
2000
2001/* This function is passed the start and end of a class range, in UTF-8 mode
2002with UCP support. It searches up the characters, looking for internal ranges of
2003characters in the "other" case. Each call returns the next one, updating the
2004start address.
2005
2006Arguments:
2007  cptr        points to starting character value; updated
2008  d           end value
2009  ocptr       where to put start of othercase range
2010  odptr       where to put end of othercase range
2011
2012Yield:        TRUE when range returned; FALSE when no more
2013*/
2014
2015static BOOL
2016get_othercase_range(unsigned int *cptr, unsigned int d, unsigned int *ocptr,
2017  unsigned int *odptr)
2018{
2019unsigned int c, othercase, next;
2020
2021for (c = *cptr; c <= d; c++)
2022  { if ((othercase = UCD_OTHERCASE(c)) != c) break; }
2023
2024if (c > d) return FALSE;
2025
2026*ocptr = othercase;
2027next = othercase + 1;
2028
2029for (++c; c <= d; c++)
2030  {
2031  if (UCD_OTHERCASE(c) != next) break;
2032  next++;
2033  }
2034
2035*odptr = next - 1;
2036*cptr = c;
2037
2038return TRUE;
2039}
2040#endif  /* SUPPORT_UCP */
2041
2042
2043
2044/*************************************************
2045*     Check if auto-possessifying is possible    *
2046*************************************************/
2047
2048/* This function is called for unlimited repeats of certain items, to see
2049whether the next thing could possibly match the repeated item. If not, it makes
2050sense to automatically possessify the repeated item.
2051
2052Arguments:
2053  op_code       the repeated op code
2054  this          data for this item, depends on the opcode
2055  utf8          TRUE in UTF-8 mode
2056  utf8_char     used for utf8 character bytes, NULL if not relevant
2057  ptr           next character in pattern
2058  options       options bits
2059  cd            contains pointers to tables etc.
2060
2061Returns:        TRUE if possessifying is wanted
2062*/
2063
2064static BOOL
2065check_auto_possessive(int op_code, int item, BOOL utf8, uschar *utf8_char,
2066  const uschar *ptr, int options, compile_data *cd)
2067{
2068int next;
2069
2070/* Skip whitespace and comments in extended mode */
2071
2072if ((options & PCRE_EXTENDED) != 0)
2073  {
2074  for (;;)
2075    {
2076    while ((cd->ctypes[*ptr] & ctype_space) != 0) ptr++;
2077    if (*ptr == '#')
2078      {
2079      while (*(++ptr) != 0)
2080        if (IS_NEWLINE(ptr)) { ptr += cd->nllen; break; }
2081      }
2082    else break;
2083    }
2084  }
2085
2086/* If the next item is one that we can handle, get its value. A non-negative
2087value is a character, a negative value is an escape value. */
2088
2089if (*ptr == '\\')
2090  {
2091  int temperrorcode = 0;
2092  next = check_escape(&ptr, &temperrorcode, cd->bracount, options, FALSE);
2093  if (temperrorcode != 0) return FALSE;
2094  ptr++;    /* Point after the escape sequence */
2095  }
2096
2097else if ((cd->ctypes[*ptr] & ctype_meta) == 0)
2098  {
2099#ifdef SUPPORT_UTF8
2100  if (utf8) { GETCHARINC(next, ptr); } else
2101#endif
2102  next = *ptr++;
2103  }
2104
2105else return FALSE;
2106
2107/* Skip whitespace and comments in extended mode */
2108
2109if ((options & PCRE_EXTENDED) != 0)
2110  {
2111  for (;;)
2112    {
2113    while ((cd->ctypes[*ptr] & ctype_space) != 0) ptr++;
2114    if (*ptr == '#')
2115      {
2116      while (*(++ptr) != 0)
2117        if (IS_NEWLINE(ptr)) { ptr += cd->nllen; break; }
2118      }
2119    else break;
2120    }
2121  }
2122
2123/* If the next thing is itself optional, we have to give up. */
2124
2125if (*ptr == '*' || *ptr == '?' || strncmp((char *)ptr, "{0,", 3) == 0)
2126  return FALSE;
2127
2128/* Now compare the next item with the previous opcode. If the previous is a
2129positive single character match, "item" either contains the character or, if
2130"item" is greater than 127 in utf8 mode, the character's bytes are in
2131utf8_char. */
2132
2133
2134/* Handle cases when the next item is a character. */
2135
2136if (next >= 0) switch(op_code)
2137  {
2138  case OP_CHAR:
2139#ifdef SUPPORT_UTF8
2140  if (utf8 && item > 127) { GETCHAR(item, utf8_char); }
2141#else
2142  (void)(utf8_char);  /* Keep compiler happy by referencing function argument */
2143#endif
2144  return item != next;
2145
2146  /* For CHARNC (caseless character) we must check the other case. If we have
2147  Unicode property support, we can use it to test the other case of
2148  high-valued characters. */
2149
2150  case OP_CHARNC:
2151#ifdef SUPPORT_UTF8
2152  if (utf8 && item > 127) { GETCHAR(item, utf8_char); }
2153#endif
2154  if (item == next) return FALSE;
2155#ifdef SUPPORT_UTF8
2156  if (utf8)
2157    {
2158    unsigned int othercase;
2159    if (next < 128) othercase = cd->fcc[next]; else
2160#ifdef SUPPORT_UCP
2161    othercase = UCD_OTHERCASE((unsigned int)next);
2162#else
2163    othercase = NOTACHAR;
2164#endif
2165    return (unsigned int)item != othercase;
2166    }
2167  else
2168#endif  /* SUPPORT_UTF8 */
2169  return (item != cd->fcc[next]);  /* Non-UTF-8 mode */
2170
2171  /* For OP_NOT, "item" must be a single-byte character. */
2172
2173  case OP_NOT:
2174  if (item == next) return TRUE;
2175  if ((options & PCRE_CASELESS) == 0) return FALSE;
2176#ifdef SUPPORT_UTF8
2177  if (utf8)
2178    {
2179    unsigned int othercase;
2180    if (next < 128) othercase = cd->fcc[next]; else
2181#ifdef SUPPORT_UCP
2182    othercase = UCD_OTHERCASE(next);
2183#else
2184    othercase = NOTACHAR;
2185#endif
2186    return (unsigned int)item == othercase;
2187    }
2188  else
2189#endif  /* SUPPORT_UTF8 */
2190  return (item == cd->fcc[next]);  /* Non-UTF-8 mode */
2191
2192  case OP_DIGIT:
2193  return next > 127 || (cd->ctypes[next] & ctype_digit) == 0;
2194
2195  case OP_NOT_DIGIT:
2196  return next <= 127 && (cd->ctypes[next] & ctype_digit) != 0;
2197
2198  case OP_WHITESPACE:
2199  return next > 127 || (cd->ctypes[next] & ctype_space) == 0;
2200
2201  case OP_NOT_WHITESPACE:
2202  return next <= 127 && (cd->ctypes[next] & ctype_space) != 0;
2203
2204  case OP_WORDCHAR:
2205  return next > 127 || (cd->ctypes[next] & ctype_word) == 0;
2206
2207  case OP_NOT_WORDCHAR:
2208  return next <= 127 && (cd->ctypes[next] & ctype_word) != 0;
2209
2210  case OP_HSPACE:
2211  case OP_NOT_HSPACE:
2212  switch(next)
2213    {
2214    case 0x09:
2215    case 0x20:
2216    case 0xa0:
2217    case 0x1680:
2218    case 0x180e:
2219    case 0x2000:
2220    case 0x2001:
2221    case 0x2002:
2222    case 0x2003:
2223    case 0x2004:
2224    case 0x2005:
2225    case 0x2006:
2226    case 0x2007:
2227    case 0x2008:
2228    case 0x2009:
2229    case 0x200A:
2230    case 0x202f:
2231    case 0x205f:
2232    case 0x3000:
2233    return op_code != OP_HSPACE;
2234    default:
2235    return op_code == OP_HSPACE;
2236    }
2237
2238  case OP_VSPACE:
2239  case OP_NOT_VSPACE:
2240  switch(next)
2241    {
2242    case 0x0a:
2243    case 0x0b:
2244    case 0x0c:
2245    case 0x0d:
2246    case 0x85:
2247    case 0x2028:
2248    case 0x2029:
2249    return op_code != OP_VSPACE;
2250    default:
2251    return op_code == OP_VSPACE;
2252    }
2253
2254  default:
2255  return FALSE;
2256  }
2257
2258
2259/* Handle the case when the next item is \d, \s, etc. */
2260
2261switch(op_code)
2262  {
2263  case OP_CHAR:
2264  case OP_CHARNC:
2265#ifdef SUPPORT_UTF8
2266  if (utf8 && item > 127) { GETCHAR(item, utf8_char); }
2267#endif
2268  switch(-next)
2269    {
2270    case ESC_d:
2271    return item > 127 || (cd->ctypes[item] & ctype_digit) == 0;
2272
2273    case ESC_D:
2274    return item <= 127 && (cd->ctypes[item] & ctype_digit) != 0;
2275
2276    case ESC_s:
2277    return item > 127 || (cd->ctypes[item] & ctype_space) == 0;
2278
2279    case ESC_S:
2280    return item <= 127 && (cd->ctypes[item] & ctype_space) != 0;
2281
2282    case ESC_w:
2283    return item > 127 || (cd->ctypes[item] & ctype_word) == 0;
2284
2285    case ESC_W:
2286    return item <= 127 && (cd->ctypes[item] & ctype_word) != 0;
2287
2288    case ESC_h:
2289    case ESC_H:
2290    switch(item)
2291      {
2292      case 0x09:
2293      case 0x20:
2294      case 0xa0:
2295      case 0x1680:
2296      case 0x180e:
2297      case 0x2000:
2298      case 0x2001:
2299      case 0x2002:
2300      case 0x2003:
2301      case 0x2004:
2302      case 0x2005:
2303      case 0x2006:
2304      case 0x2007:
2305      case 0x2008:
2306      case 0x2009:
2307      case 0x200A:
2308      case 0x202f:
2309      case 0x205f:
2310      case 0x3000:
2311      return -next != ESC_h;
2312      default:
2313      return -next == ESC_h;
2314      }
2315
2316    case ESC_v:
2317    case ESC_V:
2318    switch(item)
2319      {
2320      case 0x0a:
2321      case 0x0b:
2322      case 0x0c:
2323      case 0x0d:
2324      case 0x85:
2325      case 0x2028:
2326      case 0x2029:
2327      return -next != ESC_v;
2328      default:
2329      return -next == ESC_v;
2330      }
2331
2332    default:
2333    return FALSE;
2334    }
2335
2336  case OP_DIGIT:
2337  return next == -ESC_D || next == -ESC_s || next == -ESC_W ||
2338         next == -ESC_h || next == -ESC_v;
2339
2340  case OP_NOT_DIGIT:
2341  return next == -ESC_d;
2342
2343  case OP_WHITESPACE:
2344  return next == -ESC_S || next == -ESC_d || next == -ESC_w;
2345
2346  case OP_NOT_WHITESPACE:
2347  return next == -ESC_s || next == -ESC_h || next == -ESC_v;
2348
2349  case OP_HSPACE:
2350  return next == -ESC_S || next == -ESC_H || next == -ESC_d || next == -ESC_w;
2351
2352  case OP_NOT_HSPACE:
2353  return next == -ESC_h;
2354
2355  /* Can't have \S in here because VT matches \S (Perl anomaly) */
2356  case OP_VSPACE:
2357  return next == -ESC_V || next == -ESC_d || next == -ESC_w;
2358
2359  case OP_NOT_VSPACE:
2360  return next == -ESC_v;
2361
2362  case OP_WORDCHAR:
2363  return next == -ESC_W || next == -ESC_s || next == -ESC_h || next == -ESC_v;
2364
2365  case OP_NOT_WORDCHAR:
2366  return next == -ESC_w || next == -ESC_d;
2367
2368  default:
2369  return FALSE;
2370  }
2371
2372/* Control does not reach here */
2373}
2374
2375
2376
2377/*************************************************
2378*           Compile one branch                   *
2379*************************************************/
2380
2381/* Scan the pattern, compiling it into the a vector. If the options are
2382changed during the branch, the pointer is used to change the external options
2383bits. This function is used during the pre-compile phase when we are trying
2384to find out the amount of memory needed, as well as during the real compile
2385phase. The value of lengthptr distinguishes the two phases.
2386
2387Arguments:
2388  optionsptr     pointer to the option bits
2389  codeptr        points to the pointer to the current code point
2390  ptrptr         points to the current pattern pointer
2391  errorcodeptr   points to error code variable
2392  firstbyteptr   set to initial literal character, or < 0 (REQ_UNSET, REQ_NONE)
2393  reqbyteptr     set to the last literal character required, else < 0
2394  bcptr          points to current branch chain
2395  cd             contains pointers to tables etc.
2396  lengthptr      NULL during the real compile phase
2397                 points to length accumulator during pre-compile phase
2398
2399Returns:         TRUE on success
2400                 FALSE, with *errorcodeptr set non-zero on error
2401*/
2402
2403static BOOL
2404compile_branch(int *optionsptr, uschar **codeptr, const uschar **ptrptr,
2405  int *errorcodeptr, int *firstbyteptr, int *reqbyteptr, branch_chain *bcptr,
2406  compile_data *cd, int *lengthptr)
2407{
2408int repeat_type, op_type;
2409int repeat_min = 0, repeat_max = 0;      /* To please picky compilers */
2410int bravalue = 0;
2411int greedy_default, greedy_non_default;
2412int firstbyte, reqbyte;
2413int zeroreqbyte, zerofirstbyte;
2414int req_caseopt, reqvary, tempreqvary;
2415int options = *optionsptr;
2416int after_manual_callout = 0;
2417int length_prevgroup = 0;
2418register int c;
2419register uschar *code = *codeptr;
2420uschar *last_code = code;
2421uschar *orig_code = code;
2422uschar *tempcode;
2423BOOL inescq = FALSE;
2424BOOL groupsetfirstbyte = FALSE;
2425const uschar *ptr = *ptrptr;
2426const uschar *tempptr;
2427uschar *previous = NULL;
2428uschar *previous_callout = NULL;
2429uschar *save_hwm = NULL;
2430uschar classbits[32];
2431
2432#ifdef SUPPORT_UTF8
2433BOOL class_utf8;
2434BOOL utf8 = (options & PCRE_UTF8) != 0;
2435uschar *class_utf8data;
2436uschar *class_utf8data_base;
2437uschar utf8_char[6];
2438#else
2439BOOL utf8 = FALSE;
2440uschar *utf8_char = NULL;
2441#endif
2442
2443#ifdef DEBUG
2444if (lengthptr != NULL) DPRINTF((">> start branch\n"));
2445#endif
2446
2447/* Set up the default and non-default settings for greediness */
2448
2449greedy_default = ((options & PCRE_UNGREEDY) != 0);
2450greedy_non_default = greedy_default ^ 1;
2451
2452/* Initialize no first byte, no required byte. REQ_UNSET means "no char
2453matching encountered yet". It gets changed to REQ_NONE if we hit something that
2454matches a non-fixed char first char; reqbyte just remains unset if we never
2455find one.
2456
2457When we hit a repeat whose minimum is zero, we may have to adjust these values
2458to take the zero repeat into account. This is implemented by setting them to
2459zerofirstbyte and zeroreqbyte when such a repeat is encountered. The individual
2460item types that can be repeated set these backoff variables appropriately. */
2461
2462firstbyte = reqbyte = zerofirstbyte = zeroreqbyte = REQ_UNSET;
2463
2464/* The variable req_caseopt contains either the REQ_CASELESS value or zero,
2465according to the current setting of the caseless flag. REQ_CASELESS is a bit
2466value > 255. It is added into the firstbyte or reqbyte variables to record the
2467case status of the value. This is used only for ASCII characters. */
2468
2469req_caseopt = ((options & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;
2470
2471/* Switch on next character until the end of the branch */
2472
2473for (;; ptr++)
2474  {
2475  BOOL negate_class;
2476  BOOL should_flip_negation;
2477  BOOL possessive_quantifier;
2478  BOOL is_quantifier;
2479  BOOL is_recurse;
2480  BOOL reset_bracount;
2481  int class_charcount;
2482  int class_lastchar;
2483  int newoptions;
2484  int recno;
2485  int refsign;
2486  int skipbytes;
2487  int subreqbyte;
2488  int subfirstbyte;
2489  int terminator;
2490  int mclength;
2491  uschar mcbuffer[8];
2492
2493  /* Get next byte in the pattern */
2494
2495  c = *ptr;
2496
2497  /* If we are in the pre-compile phase, accumulate the length used for the
2498  previous cycle of this loop. */
2499
2500  if (lengthptr != NULL)
2501    {
2502#ifdef DEBUG
2503    if (code > cd->hwm) cd->hwm = code;                 /* High water info */
2504#endif
2505    if (code > cd->start_workspace + COMPILE_WORK_SIZE) /* Check for overrun */
2506      {
2507      *errorcodeptr = ERR52;
2508      goto FAILED;
2509      }
2510
2511    /* There is at least one situation where code goes backwards: this is the
2512    case of a zero quantifier after a class (e.g. [ab]{0}). At compile time,
2513    the class is simply eliminated. However, it is created first, so we have to
2514    allow memory for it. Therefore, don't ever reduce the length at this point.
2515    */
2516
2517    if (code < last_code) code = last_code;
2518
2519    /* Paranoid check for integer overflow */
2520
2521    if (OFLOW_MAX - *lengthptr < code - last_code)
2522      {
2523      *errorcodeptr = ERR20;
2524      goto FAILED;
2525      }
2526
2527    *lengthptr += code - last_code;
2528    DPRINTF(("length=%d added %d c=%c\n", *lengthptr, code - last_code, c));
2529
2530    /* If "previous" is set and it is not at the start of the work space, move
2531    it back to there, in order to avoid filling up the work space. Otherwise,
2532    if "previous" is NULL, reset the current code pointer to the start. */
2533
2534    if (previous != NULL)
2535      {
2536      if (previous > orig_code)
2537        {
2538        memmove(orig_code, previous, code - previous);
2539        code -= previous - orig_code;
2540        previous = orig_code;
2541        }
2542      }
2543    else code = orig_code;
2544
2545    /* Remember where this code item starts so we can pick up the length
2546    next time round. */
2547
2548    last_code = code;
2549    }
2550
2551  /* In the real compile phase, just check the workspace used by the forward
2552  reference list. */
2553
2554  else if (cd->hwm > cd->start_workspace + COMPILE_WORK_SIZE)
2555    {
2556    *errorcodeptr = ERR52;
2557    goto FAILED;
2558    }
2559
2560  /* If in \Q...\E, check for the end; if not, we have a literal */
2561
2562  if (inescq && c != 0)
2563    {
2564    if (c == '\\' && ptr[1] == 'E')
2565      {
2566      inescq = FALSE;
2567      ptr++;
2568      continue;
2569      }
2570    else
2571      {
2572      if (previous_callout != NULL)
2573        {
2574        if (lengthptr == NULL)  /* Don't attempt in pre-compile phase */
2575          complete_callout(previous_callout, ptr, cd);
2576        previous_callout = NULL;
2577        }
2578      if ((options & PCRE_AUTO_CALLOUT) != 0)
2579        {
2580        previous_callout = code;
2581        code = auto_callout(code, ptr, cd);
2582        }
2583      goto NORMAL_CHAR;
2584      }
2585    }
2586
2587  /* Fill in length of a previous callout, except when the next thing is
2588  a quantifier. */
2589
2590  is_quantifier = c == '*' || c == '+' || c == '?' ||
2591    (c == '{' && is_counted_repeat(ptr+1));
2592
2593  if (!is_quantifier && previous_callout != NULL &&
2594       after_manual_callout-- <= 0)
2595    {
2596    if (lengthptr == NULL)      /* Don't attempt in pre-compile phase */
2597      complete_callout(previous_callout, ptr, cd);
2598    previous_callout = NULL;
2599    }
2600
2601  /* In extended mode, skip white space and comments */
2602
2603  if ((options & PCRE_EXTENDED) != 0)
2604    {
2605    if ((cd->ctypes[c] & ctype_space) != 0) continue;
2606    if (c == '#')
2607      {
2608      while (*(++ptr) != 0)
2609        {
2610        if (IS_NEWLINE(ptr)) { ptr += cd->nllen - 1; break; }
2611        }
2612      if (*ptr != 0) continue;
2613
2614      /* Else fall through to handle end of string */
2615      c = 0;
2616      }
2617    }
2618
2619  /* No auto callout for quantifiers. */
2620
2621  if ((options & PCRE_AUTO_CALLOUT) != 0 && !is_quantifier)
2622    {
2623    previous_callout = code;
2624    code = auto_callout(code, ptr, cd);
2625    }
2626
2627  switch(c)
2628    {
2629    /* ===================================================================*/
2630    case 0:                        /* The branch terminates at string end */
2631    case '|':                      /* or | or ) */
2632    case ')':
2633    *firstbyteptr = firstbyte;
2634    *reqbyteptr = reqbyte;
2635    *codeptr = code;
2636    *ptrptr = ptr;
2637    if (lengthptr != NULL)
2638      {
2639      if (OFLOW_MAX - *lengthptr < code - last_code)
2640        {
2641        *errorcodeptr = ERR20;
2642        goto FAILED;
2643        }
2644      *lengthptr += code - last_code;   /* To include callout length */
2645      DPRINTF((">> end branch\n"));
2646      }
2647    return TRUE;
2648
2649
2650    /* ===================================================================*/
2651    /* Handle single-character metacharacters. In multiline mode, ^ disables
2652    the setting of any following char as a first character. */
2653
2654    case '^':
2655    if ((options & PCRE_MULTILINE) != 0)
2656      {
2657      if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
2658      }
2659    previous = NULL;
2660    *code++ = OP_CIRC;
2661    break;
2662
2663    case '$':
2664    previous = NULL;
2665    *code++ = OP_DOLL;
2666    break;
2667
2668    /* There can never be a first char if '.' is first, whatever happens about
2669    repeats. The value of reqbyte doesn't change either. */
2670
2671    case '.':
2672    if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
2673    zerofirstbyte = firstbyte;
2674    zeroreqbyte = reqbyte;
2675    previous = code;
2676    *code++ = ((options & PCRE_DOTALL) != 0)? OP_ALLANY: OP_ANY;
2677    break;
2678
2679
2680    /* ===================================================================*/
2681    /* Character classes. If the included characters are all < 256, we build a
2682    32-byte bitmap of the permitted characters, except in the special case
2683    where there is only one such character. For negated classes, we build the
2684    map as usual, then invert it at the end. However, we use a different opcode
2685    so that data characters > 255 can be handled correctly.
2686
2687    If the class contains characters outside the 0-255 range, a different
2688    opcode is compiled. It may optionally have a bit map for characters < 256,
2689    but those above are are explicitly listed afterwards. A flag byte tells
2690    whether the bitmap is present, and whether this is a negated class or not.
2691
2692    In JavaScript compatibility mode, an isolated ']' causes an error. In
2693    default (Perl) mode, it is treated as a data character. */
2694
2695    case ']':
2696    if ((cd->external_options & PCRE_JAVASCRIPT_COMPAT) != 0)
2697      {
2698      *errorcodeptr = ERR64;
2699      goto FAILED;
2700      }
2701    goto NORMAL_CHAR;
2702
2703    case '[':
2704    previous = code;
2705
2706    /* PCRE supports POSIX class stuff inside a class. Perl gives an error if
2707    they are encountered at the top level, so we'll do that too. */
2708
2709    if ((ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
2710        check_posix_syntax(ptr, &tempptr))
2711      {
2712      *errorcodeptr = (ptr[1] == ':')? ERR13 : ERR31;
2713      goto FAILED;
2714      }
2715
2716    /* If the first character is '^', set the negation flag and skip it. Also,
2717    if the first few characters (either before or after ^) are \Q\E or \E we
2718    skip them too. This makes for compatibility with Perl. */
2719
2720    negate_class = FALSE;
2721    for (;;)
2722      {
2723      c = *(++ptr);
2724      if (c == '\\')
2725        {
2726        if (ptr[1] == 'E') ptr++;
2727          else if (strncmp((const char *)ptr+1, "Q\\E", 3) == 0) ptr += 3;
2728            else break;
2729        }
2730      else if (!negate_class && c == '^')
2731        negate_class = TRUE;
2732      else break;
2733      }
2734
2735    /* Empty classes are allowed in JavaScript compatibility mode. Otherwise,
2736    an initial ']' is taken as a data character -- the code below handles
2737    that. In JS mode, [] must always fail, so generate OP_FAIL, whereas
2738    [^] must match any character, so generate OP_ALLANY. */
2739
2740    if (c ==']' && (cd->external_options & PCRE_JAVASCRIPT_COMPAT) != 0)
2741      {
2742      *code++ = negate_class? OP_ALLANY : OP_FAIL;
2743      if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
2744      zerofirstbyte = firstbyte;
2745      break;
2746      }
2747
2748    /* If a class contains a negative special such as \S, we need to flip the
2749    negation flag at the end, so that support for characters > 255 works
2750    correctly (they are all included in the class). */
2751
2752    should_flip_negation = FALSE;
2753
2754    /* Keep a count of chars with values < 256 so that we can optimize the case
2755    of just a single character (as long as it's < 256). However, For higher
2756    valued UTF-8 characters, we don't yet do any optimization. */
2757
2758    class_charcount = 0;
2759    class_lastchar = -1;
2760
2761    /* Initialize the 32-char bit map to all zeros. We build the map in a
2762    temporary bit of memory, in case the class contains only 1 character (less
2763    than 256), because in that case the compiled code doesn't use the bit map.
2764    */
2765
2766    memset(classbits, 0, 32 * sizeof(uschar));
2767
2768#ifdef SUPPORT_UTF8
2769    class_utf8 = FALSE;                       /* No chars >= 256 */
2770    class_utf8data = code + LINK_SIZE + 2;    /* For UTF-8 items */
2771    class_utf8data_base = class_utf8data;     /* For resetting in pass 1 */
2772#endif
2773
2774    /* Process characters until ] is reached. By writing this as a "do" it
2775    means that an initial ] is taken as a data character. At the start of the
2776    loop, c contains the first byte of the character. */
2777
2778    if (c != 0) do
2779      {
2780      const uschar *oldptr;
2781
2782#ifdef SUPPORT_UTF8
2783      if (utf8 && c > 127)
2784        {                           /* Braces are required because the */
2785        GETCHARLEN(c, ptr, ptr);    /* macro generates multiple statements */
2786        }
2787
2788      /* In the pre-compile phase, accumulate the length of any UTF-8 extra
2789      data and reset the pointer. This is so that very large classes that
2790      contain a zillion UTF-8 characters no longer overwrite the work space
2791      (which is on the stack). */
2792
2793      if (lengthptr != NULL)
2794        {
2795        *lengthptr += class_utf8data - class_utf8data_base;
2796        class_utf8data = class_utf8data_base;
2797        }
2798
2799#endif
2800
2801      /* Inside \Q...\E everything is literal except \E */
2802
2803      if (inescq)
2804        {
2805        if (c == '\\' && ptr[1] == 'E')     /* If we are at \E */
2806          {
2807          inescq = FALSE;                   /* Reset literal state */
2808          ptr++;                            /* Skip the 'E' */
2809          continue;                         /* Carry on with next */
2810          }
2811        goto CHECK_RANGE;                   /* Could be range if \E follows */
2812        }
2813
2814      /* Handle POSIX class names. Perl allows a negation extension of the
2815      form [:^name:]. A square bracket that doesn't match the syntax is
2816      treated as a literal. We also recognize the POSIX constructions
2817      [.ch.] and [=ch=] ("collating elements") and fault them, as Perl
2818      5.6 and 5.8 do. */
2819
2820      if (c == '[' &&
2821          (ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
2822          check_posix_syntax(ptr, &tempptr))
2823        {
2824        BOOL local_negate = FALSE;
2825        int posix_class, taboffset, tabopt;
2826        register const uschar *cbits = cd->cbits;
2827        uschar pbits[32];
2828
2829        if (ptr[1] != ':')
2830          {
2831          *errorcodeptr = ERR31;
2832          goto FAILED;
2833          }
2834
2835        ptr += 2;
2836        if (*ptr == '^')
2837          {
2838          local_negate = TRUE;
2839          should_flip_negation = TRUE;  /* Note negative special */
2840          ptr++;
2841          }
2842
2843        posix_class = check_posix_name(ptr, tempptr - ptr);
2844        if (posix_class < 0)
2845          {
2846          *errorcodeptr = ERR30;
2847          goto FAILED;
2848          }
2849
2850        /* If matching is caseless, upper and lower are converted to
2851        alpha. This relies on the fact that the class table starts with
2852        alpha, lower, upper as the first 3 entries. */
2853
2854        if ((options & PCRE_CASELESS) != 0 && posix_class <= 2)
2855          posix_class = 0;
2856
2857        /* We build the bit map for the POSIX class in a chunk of local store
2858        because we may be adding and subtracting from it, and we don't want to
2859        subtract bits that may be in the main map already. At the end we or the
2860        result into the bit map that is being built. */
2861
2862        posix_class *= 3;
2863
2864        /* Copy in the first table (always present) */
2865
2866        memcpy(pbits, cbits + posix_class_maps[posix_class],
2867          32 * sizeof(uschar));
2868
2869        /* If there is a second table, add or remove it as required. */
2870
2871        taboffset = posix_class_maps[posix_class + 1];
2872        tabopt = posix_class_maps[posix_class + 2];
2873
2874        if (taboffset >= 0)
2875          {
2876          if (tabopt >= 0)
2877            for (c = 0; c < 32; c++) pbits[c] |= cbits[c + taboffset];
2878          else
2879            for (c = 0; c < 32; c++) pbits[c] &= ~cbits[c + taboffset];
2880          }
2881
2882        /* Not see if we need to remove any special characters. An option
2883        value of 1 removes vertical space and 2 removes underscore. */
2884
2885        if (tabopt < 0) tabopt = -tabopt;
2886        if (tabopt == 1) pbits[1] &= ~0x3c;
2887          else if (tabopt == 2) pbits[11] &= 0x7f;
2888
2889        /* Add the POSIX table or its complement into the main table that is
2890        being built and we are done. */
2891
2892        if (local_negate)
2893          for (c = 0; c < 32; c++) classbits[c] |= ~pbits[c];
2894        else
2895          for (c = 0; c < 32; c++) classbits[c] |= pbits[c];
2896
2897        ptr = tempptr + 1;
2898        class_charcount = 10;  /* Set > 1; assumes more than 1 per class */
2899        continue;    /* End of POSIX syntax handling */
2900        }
2901
2902      /* Backslash may introduce a single character, or it may introduce one
2903      of the specials, which just set a flag. The sequence \b is a special
2904      case. Inside a class (and only there) it is treated as backspace.
2905      Elsewhere it marks a word boundary. Other escapes have preset maps ready
2906      to 'or' into the one we are building. We assume they have more than one
2907      character in them, so set class_charcount bigger than one. */
2908
2909      if (c == '\\')
2910        {
2911        c = check_escape(&ptr, errorcodeptr, cd->bracount, options, TRUE);
2912        if (*errorcodeptr != 0) goto FAILED;
2913
2914        if (-c == ESC_b) c = '\b';       /* \b is backspace in a class */
2915        else if (-c == ESC_X) c = 'X';   /* \X is literal X in a class */
2916        else if (-c == ESC_R) c = 'R';   /* \R is literal R in a class */
2917        else if (-c == ESC_Q)            /* Handle start of quoted string */
2918          {
2919          if (ptr[1] == '\\' && ptr[2] == 'E')
2920            {
2921            ptr += 2; /* avoid empty string */
2922            }
2923          else inescq = TRUE;
2924          continue;
2925          }
2926        else if (-c == ESC_E) continue;  /* Ignore orphan \E */
2927
2928        if (c < 0)
2929          {
2930          register const uschar *cbits = cd->cbits;
2931          class_charcount += 2;     /* Greater than 1 is what matters */
2932
2933          /* Save time by not doing this in the pre-compile phase. */
2934
2935          if (lengthptr == NULL) switch (-c)
2936            {
2937            case ESC_d:
2938            for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_digit];
2939            continue;
2940
2941            case ESC_D:
2942            should_flip_negation = TRUE;
2943            for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_digit];
2944            continue;
2945
2946            case ESC_w:
2947            for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_word];
2948            continue;
2949
2950            case ESC_W:
2951            should_flip_negation = TRUE;
2952            for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_word];
2953            continue;
2954
2955            case ESC_s:
2956            for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_space];
2957            classbits[1] &= ~0x08;   /* Perl 5.004 onwards omits VT from \s */
2958            continue;
2959
2960            case ESC_S:
2961            should_flip_negation = TRUE;
2962            for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_space];
2963            classbits[1] |= 0x08;    /* Perl 5.004 onwards omits VT from \s */
2964            continue;
2965
2966            default:    /* Not recognized; fall through */
2967            break;      /* Need "default" setting to stop compiler warning. */
2968            }
2969
2970          /* In the pre-compile phase, just do the recognition. */
2971
2972          else if (c == -ESC_d || c == -ESC_D || c == -ESC_w ||
2973                   c == -ESC_W || c == -ESC_s || c == -ESC_S) continue;
2974
2975          /* We need to deal with \H, \h, \V, and \v in both phases because
2976          they use extra memory. */
2977
2978          if (-c == ESC_h)
2979            {
2980            SETBIT(classbits, 0x09); /* VT */
2981            SETBIT(classbits, 0x20); /* SPACE */
2982            SETBIT(classbits, 0xa0); /* NSBP */
2983#ifdef SUPPORT_UTF8
2984            if (utf8)
2985              {
2986              class_utf8 = TRUE;
2987              *class_utf8data++ = XCL_SINGLE;
2988              class_utf8data += _pcre_ord2utf8(0x1680, class_utf8data);
2989              *class_utf8data++ = XCL_SINGLE;
2990              class_utf8data += _pcre_ord2utf8(0x180e, class_utf8data);
2991              *class_utf8data++ = XCL_RANGE;
2992              class_utf8data += _pcre_ord2utf8(0x2000, class_utf8data);
2993              class_utf8data += _pcre_ord2utf8(0x200A, class_utf8data);
2994              *class_utf8data++ = XCL_SINGLE;
2995              class_utf8data += _pcre_ord2utf8(0x202f, class_utf8data);
2996              *class_utf8data++ = XCL_SINGLE;
2997              class_utf8data += _pcre_ord2utf8(0x205f, class_utf8data);
2998              *class_utf8data++ = XCL_SINGLE;
2999              class_utf8data += _pcre_ord2utf8(0x3000, class_utf8data);
3000              }
3001#endif
3002            continue;
3003            }
3004
3005          if (-c == ESC_H)
3006            {
3007            for (c = 0; c < 32; c++)
3008              {
3009              int x = 0xff;
3010              switch (c)
3011                {
3012                case 0x09/8: x ^= 1 << (0x09%8); break;
3013                case 0x20/8: x ^= 1 << (0x20%8); break;
3014                case 0xa0/8: x ^= 1 << (0xa0%8); break;
3015                default: break;
3016                }
3017              classbits[c] |= x;
3018              }
3019
3020#ifdef SUPPORT_UTF8
3021            if (utf8)
3022              {
3023              class_utf8 = TRUE;
3024              *class_utf8data++ = XCL_RANGE;
3025              class_utf8data += _pcre_ord2utf8(0x0100, class_utf8data);
3026              class_utf8data += _pcre_ord2utf8(0x167f, class_utf8data);
3027              *class_utf8data++ = XCL_RANGE;
3028              class_utf8data += _pcre_ord2utf8(0x1681, class_utf8data);
3029              class_utf8data += _pcre_ord2utf8(0x180d, class_utf8data);
3030              *class_utf8data++ = XCL_RANGE;
3031              class_utf8data += _pcre_ord2utf8(0x180f, class_utf8data);
3032              class_utf8data += _pcre_ord2utf8(0x1fff, class_utf8data);
3033              *class_utf8data++ = XCL_RANGE;
3034              class_utf8data += _pcre_ord2utf8(0x200B, class_utf8data);
3035              class_utf8data += _pcre_ord2utf8(0x202e, class_utf8data);
3036              *class_utf8data++ = XCL_RANGE;
3037              class_utf8data += _pcre_ord2utf8(0x2030, class_utf8data);
3038              class_utf8data += _pcre_ord2utf8(0x205e, class_utf8data);
3039              *class_utf8data++ = XCL_RANGE;
3040              class_utf8data += _pcre_ord2utf8(0x2060, class_utf8data);
3041              class_utf8data += _pcre_ord2utf8(0x2fff, class_utf8data);
3042              *class_utf8data++ = XCL_RANGE;
3043              class_utf8data += _pcre_ord2utf8(0x3001, class_utf8data);
3044              class_utf8data += _pcre_ord2utf8(0x7fffffff, class_utf8data);
3045              }
3046#endif
3047            continue;
3048            }
3049
3050          if (-c == ESC_v)
3051            {
3052            SETBIT(classbits, 0x0a); /* LF */
3053            SETBIT(classbits, 0x0b); /* VT */
3054            SETBIT(classbits, 0x0c); /* FF */
3055            SETBIT(classbits, 0x0d); /* CR */
3056            SETBIT(classbits, 0x85); /* NEL */
3057#ifdef SUPPORT_UTF8
3058            if (utf8)
3059              {
3060              class_utf8 = TRUE;
3061              *class_utf8data++ = XCL_RANGE;
3062              class_utf8data += _pcre_ord2utf8(0x2028, class_utf8data);
3063              class_utf8data += _pcre_ord2utf8(0x2029, class_utf8data);
3064              }
3065#endif
3066            continue;
3067            }
3068
3069          if (-c == ESC_V)
3070            {
3071            for (c = 0; c < 32; c++)
3072              {
3073              int x = 0xff;
3074              switch (c)
3075                {
3076                case 0x0a/8: x ^= 1 << (0x0a%8);
3077                             x ^= 1 << (0x0b%8);
3078                             x ^= 1 << (0x0c%8);
3079                             x ^= 1 << (0x0d%8);
3080                             break;
3081                case 0x85/8: x ^= 1 << (0x85%8); break;
3082                default: break;
3083                }
3084              classbits[c] |= x;
3085              }
3086
3087#ifdef SUPPORT_UTF8
3088            if (utf8)
3089              {
3090              class_utf8 = TRUE;
3091              *class_utf8data++ = XCL_RANGE;
3092              class_utf8data += _pcre_ord2utf8(0x0100, class_utf8data);
3093              class_utf8data += _pcre_ord2utf8(0x2027, class_utf8data);
3094              *class_utf8data++ = XCL_RANGE;
3095              class_utf8data += _pcre_ord2utf8(0x2029, class_utf8data);
3096              class_utf8data += _pcre_ord2utf8(0x7fffffff, class_utf8data);
3097              }
3098#endif
3099            continue;
3100            }
3101
3102          /* We need to deal with \P and \p in both phases. */
3103
3104#ifdef SUPPORT_UCP
3105          if (-c == ESC_p || -c == ESC_P)
3106            {
3107            BOOL negated;
3108            int pdata;
3109            int ptype = get_ucp(&ptr, &negated, &pdata, errorcodeptr);
3110            if (ptype < 0) goto FAILED;
3111            class_utf8 = TRUE;
3112            *class_utf8data++ = ((-c == ESC_p) != negated)?
3113              XCL_PROP : XCL_NOTPROP;
3114            *class_utf8data++ = ptype;
3115            *class_utf8data++ = pdata;
3116            class_charcount -= 2;   /* Not a < 256 character */
3117            continue;
3118            }
3119#endif
3120          /* Unrecognized escapes are faulted if PCRE is running in its
3121          strict mode. By default, for compatibility with Perl, they are
3122          treated as literals. */
3123
3124          if ((options & PCRE_EXTRA) != 0)
3125            {
3126            *errorcodeptr = ERR7;
3127            goto FAILED;
3128            }
3129
3130          class_charcount -= 2;  /* Undo the default count from above */
3131          c = *ptr;              /* Get the final character and fall through */
3132          }
3133
3134        /* Fall through if we have a single character (c >= 0). This may be
3135        greater than 256 in UTF-8 mode. */
3136
3137        }   /* End of backslash handling */
3138
3139      /* A single character may be followed by '-' to form a range. However,
3140      Perl does not permit ']' to be the end of the range. A '-' character
3141      at the end is treated as a literal. Perl ignores orphaned \E sequences
3142      entirely. The code for handling \Q and \E is messy. */
3143
3144      CHECK_RANGE:
3145      while (ptr[1] == '\\' && ptr[2] == 'E')
3146        {
3147        inescq = FALSE;
3148        ptr += 2;
3149        }
3150
3151      oldptr = ptr;
3152
3153      /* Remember \r or \n */
3154
3155      if (c == '\r' || c == '\n') cd->external_flags |= PCRE_HASCRORLF;
3156
3157      /* Check for range */
3158
3159      if (!inescq && ptr[1] == '-')
3160        {
3161        int d;
3162        ptr += 2;
3163        while (*ptr == '\\' && ptr[1] == 'E') ptr += 2;
3164
3165        /* If we hit \Q (not followed by \E) at this point, go into escaped
3166        mode. */
3167
3168        while (*ptr == '\\' && ptr[1] == 'Q')
3169          {
3170          ptr += 2;
3171          if (*ptr == '\\' && ptr[1] == 'E') { ptr += 2; continue; }
3172          inescq = TRUE;
3173          break;
3174          }
3175
3176        if (*ptr == 0 || (!inescq && *ptr == ']'))
3177          {
3178          ptr = oldptr;
3179          goto LONE_SINGLE_CHARACTER;
3180          }
3181
3182#ifdef SUPPORT_UTF8
3183        if (utf8)
3184          {                           /* Braces are required because the */
3185          GETCHARLEN(d, ptr, ptr);    /* macro generates multiple statements */
3186          }
3187        else
3188#endif
3189        d = *ptr;  /* Not UTF-8 mode */
3190
3191        /* The second part of a range can be a single-character escape, but
3192        not any of the other escapes. Perl 5.6 treats a hyphen as a literal
3193        in such circumstances. */
3194
3195        if (!inescq && d == '\\')
3196          {
3197          d = check_escape(&ptr, errorcodeptr, cd->bracount, options, TRUE);
3198          if (*errorcodeptr != 0) goto FAILED;
3199
3200          /* \b is backspace; \X is literal X; \R is literal R; any other
3201          special means the '-' was literal */
3202
3203          if (d < 0)
3204            {
3205            if (d == -ESC_b) d = '\b';
3206            else if (d == -ESC_X) d = 'X';
3207            else if (d == -ESC_R) d = 'R'; else
3208              {
3209              ptr = oldptr;
3210              goto LONE_SINGLE_CHARACTER;  /* A few lines below */
3211              }
3212            }
3213          }
3214
3215        /* Check that the two values are in the correct order. Optimize
3216        one-character ranges */
3217
3218        if (d < c)
3219          {
3220          *errorcodeptr = ERR8;
3221          goto FAILED;
3222          }
3223
3224        if (d == c) goto LONE_SINGLE_CHARACTER;  /* A few lines below */
3225
3226        /* Remember \r or \n */
3227
3228        if (d == '\r' || d == '\n') cd->external_flags |= PCRE_HASCRORLF;
3229
3230        /* In UTF-8 mode, if the upper limit is > 255, or > 127 for caseless
3231        matching, we have to use an XCLASS with extra data items. Caseless
3232        matching for characters > 127 is available only if UCP support is
3233        available. */
3234
3235#ifdef SUPPORT_UTF8
3236        if (utf8 && (d > 255 || ((options & PCRE_CASELESS) != 0 && d > 127)))
3237          {
3238          class_utf8 = TRUE;
3239
3240          /* With UCP support, we can find the other case equivalents of
3241          the relevant characters. There may be several ranges. Optimize how
3242          they fit with the basic range. */
3243
3244#ifdef SUPPORT_UCP
3245          if ((options & PCRE_CASELESS) != 0)
3246            {
3247            unsigned int occ, ocd;
3248            unsigned int cc = c;
3249            unsigned int origd = d;
3250            while (get_othercase_range(&cc, origd, &occ, &ocd))
3251              {
3252              if (occ >= (unsigned int)c &&
3253                  ocd <= (unsigned int)d)
3254                continue;                          /* Skip embedded ranges */
3255
3256              if (occ < (unsigned int)&&
3257                  ocd >= (unsigned int)c - 1)      /* Extend the basic range */
3258                {                                  /* if there is overlap,   */
3259                c = occ;                           /* noting that if occ < c */
3260                continue;                          /* we can't have ocd > d  */
3261                }                                  /* because a subrange is  */
3262              if (ocd > (unsigned int)d &&
3263                  occ <= (unsigned int)d + 1)      /* always shorter than    */
3264                {                                  /* the basic range.       */
3265                d = ocd;
3266                continue;
3267                }
3268
3269              if (occ == ocd)
3270                {
3271                *class_utf8data++ = XCL_SINGLE;
3272                }
3273              else
3274                {
3275                *class_utf8data++ = XCL_RANGE;
3276                class_utf8data += _pcre_ord2utf8(occ, class_utf8data);
3277                }
3278              class_utf8data += _pcre_ord2utf8(ocd, class_utf8data);
3279              }
3280            }
3281#endif  /* SUPPORT_UCP */
3282
3283          /* Now record the original range, possibly modified for UCP caseless
3284          overlapping ranges. */
3285
3286          *class_utf8data++ = XCL_RANGE;
3287          class_utf8data += _pcre_ord2utf8(c, class_utf8data);
3288          class_utf8data += _pcre_ord2utf8(d, class_utf8data);
3289
3290          /* With UCP support, we are done. Without UCP support, there is no
3291          caseless matching for UTF-8 characters > 127; we can use the bit map
3292          for the smaller ones. */
3293
3294#ifdef SUPPORT_UCP
3295          continue;    /* With next character in the class */
3296#else
3297          if ((options & PCRE_CASELESS) == 0 || c > 127) continue;
3298
3299          /* Adjust upper limit and fall through to set up the map */
3300
3301          d = 127;
3302
3303#endif  /* SUPPORT_UCP */
3304          }
3305#endif  /* SUPPORT_UTF8 */
3306
3307        /* We use the bit map for all cases when not in UTF-8 mode; else
3308        ranges that lie entirely within 0-127 when there is UCP support; else
3309        for partial ranges without UCP support. */
3310
3311        class_charcount += d - c + 1;
3312        class_lastchar = d;
3313
3314        /* We can save a bit of time by skipping this in the pre-compile. */
3315
3316        if (lengthptr == NULL) for (; c <= d; c++)
3317          {
3318          classbits[c/8] |= (1 << (c&7));
3319          if ((options & PCRE_CASELESS) != 0)
3320            {
3321            int uc = cd->fcc[c];           /* flip case */
3322            classbits[uc/8] |= (1 << (uc&7));
3323            }
3324          }
3325
3326        continue;   /* Go get the next char in the class */
3327        }
3328
3329      /* Handle a lone single character - we can get here for a normal
3330      non-escape char, or after \ that introduces a single character or for an
3331      apparent range that isn't. */
3332
3333      LONE_SINGLE_CHARACTER:
3334
3335      /* Handle a character that cannot go in the bit map */
3336
3337#ifdef SUPPORT_UTF8
3338      if (utf8 && (c > 255 || ((options & PCRE_CASELESS) != 0 && c > 127)))
3339        {
3340        class_utf8 = TRUE;
3341        *class_utf8data++ = XCL_SINGLE;
3342        class_utf8data += _pcre_ord2utf8(c, class_utf8data);
3343
3344#ifdef SUPPORT_UCP
3345        if ((options & PCRE_CASELESS) != 0)
3346          {
3347          unsigned int othercase;
3348          if ((othercase = UCD_OTHERCASE(c)) != c)
3349            {
3350            *class_utf8data++ = XCL_SINGLE;
3351            class_utf8data += _pcre_ord2utf8(othercase, class_utf8data);
3352            }
3353          }
3354#endif  /* SUPPORT_UCP */
3355
3356        }
3357      else
3358#endif  /* SUPPORT_UTF8 */
3359
3360      /* Handle a single-byte character */
3361        {
3362        classbits[c/8] |= (1 << (c&7));
3363        if ((options & PCRE_CASELESS) != 0)
3364          {
3365          c = cd->fcc[c];   /* flip case */
3366          classbits[c/8] |= (1 << (c&7));
3367          }
3368        class_charcount++;
3369        class_lastchar = c;
3370        }
3371      }
3372
3373    /* Loop until ']' reached. This "while" is the end of the "do" above. */
3374
3375    while ((c = *(++ptr)) != 0 && (c != ']' || inescq));
3376
3377    if (c == 0)                          /* Missing terminating ']' */
3378      {
3379      *errorcodeptr = ERR6;
3380      goto FAILED;
3381      }
3382
3383
3384/* This code has been disabled because it would mean that \s counts as
3385an explicit \r or \n reference, and that's not really what is wanted. Now
3386we set the flag only if there is a literal "\r" or "\n" in the class. */
3387
3388#if 0
3389    /* Remember whether \r or \n are in this class */
3390
3391    if (negate_class)
3392      {
3393      if ((classbits[1] & 0x24) != 0x24) cd->external_flags |= PCRE_HASCRORLF;
3394      }
3395    else
3396      {
3397      if ((classbits[1] & 0x24) != 0) cd->external_flags |= PCRE_HASCRORLF;
3398      }
3399#endif
3400
3401
3402    /* If class_charcount is 1, we saw precisely one character whose value is
3403    less than 256. As long as there were no characters >= 128 and there was no
3404    use of \p or \P, in other words, no use of any XCLASS features, we can
3405    optimize.
3406
3407    In UTF-8 mode, we can optimize the negative case only if there were no
3408    characters >= 128 because OP_NOT and the related opcodes like OP_NOTSTAR
3409    operate on single-bytes only. This is an historical hangover. Maybe one day
3410    we can tidy these opcodes to handle multi-byte characters.
3411
3412    The optimization throws away the bit map. We turn the item into a
3413    1-character OP_CHAR[NC] if it's positive, or OP_NOT if it's negative. Note
3414    that OP_NOT does not support multibyte characters. In the positive case, it
3415    can cause firstbyte to be set. Otherwise, there can be no first char if
3416    this item is first, whatever repeat count may follow. In the case of
3417    reqbyte, save the previous value for reinstating. */
3418
3419#ifdef SUPPORT_UTF8
3420    if (class_charcount == 1 && !class_utf8 &&
3421      (!utf8 || !negate_class || class_lastchar < 128))
3422#else
3423    if (class_charcount == 1)
3424#endif
3425      {
3426      zeroreqbyte = reqbyte;
3427
3428      /* The OP_NOT opcode works on one-byte characters only. */
3429
3430      if (negate_class)
3431        {
3432        if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
3433        zerofirstbyte = firstbyte;
3434        *code++ = OP_NOT;
3435        *code++ = class_lastchar;
3436        break;
3437        }
3438
3439      /* For a single, positive character, get the value into mcbuffer, and
3440      then we can handle this with the normal one-character code. */
3441
3442#ifdef SUPPORT_UTF8
3443      if (utf8 && class_lastchar > 127)
3444        mclength = _pcre_ord2utf8(class_lastchar, mcbuffer);
3445      else
3446#endif
3447        {
3448        mcbuffer[0] = class_lastchar;
3449        mclength = 1;
3450        }
3451      goto ONE_CHAR;
3452      }       /* End of 1-char optimization */
3453
3454    /* The general case - not the one-char optimization. If this is the first
3455    thing in the branch, there can be no first char setting, whatever the
3456    repeat count. Any reqbyte setting must remain unchanged after any kind of
3457    repeat. */
3458
3459    if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
3460    zerofirstbyte = firstbyte;
3461    zeroreqbyte = reqbyte;
3462
3463    /* If there are characters with values > 255, we have to compile an
3464    extended class, with its own opcode, unless there was a negated special
3465    such as \S in the class, because in that case all characters > 255 are in
3466    the class, so any that were explicitly given as well can be ignored. If
3467    (when there are explicit characters > 255 that must be listed) there are no
3468    characters < 256, we can omit the bitmap in the actual compiled code. */
3469
3470#ifdef SUPPORT_UTF8
3471    if (class_utf8 && !should_flip_negation)
3472      {
3473      *class_utf8data++ = XCL_END;    /* Marks the end of extra data */
3474      *code++ = OP_XCLASS;
3475      code += LINK_SIZE;
3476      *code = negate_class? XCL_NOT : 0;
3477
3478      /* If the map is required, move up the extra data to make room for it;
3479      otherwise just move the code pointer to the end of the extra data. */
3480
3481      if (class_charcount > 0)
3482        {
3483        *code++ |= XCL_MAP;
3484        memmove(code + 32, code, class_utf8data - code);
3485        memcpy(code, classbits, 32);
3486        code = class_utf8data + 32;
3487        }
3488      else code = class_utf8data;
3489
3490      /* Now fill in the complete length of the item */
3491
3492      PUT(previous, 1, code - previous);
3493      break;   /* End of class handling */
3494      }
3495#endif
3496
3497    /* If there are no characters > 255, set the opcode to OP_CLASS or
3498    OP_NCLASS, depending on whether the whole class was negated and whether
3499    there were negative specials such as \S in the class. Then copy the 32-byte
3500    map into the code vector, negating it if necessary. */
3501
3502    *code++ = (negate_class == should_flip_negation) ? OP_CLASS : OP_NCLASS;
3503    if (negate_class)
3504      {
3505      if (lengthptr == NULL)    /* Save time in the pre-compile phase */
3506        for (c = 0; c < 32; c++) code[c] = ~classbits[c];
3507      }
3508    else
3509      {
3510      memcpy(code, classbits, 32);
3511      }
3512    code += 32;
3513    break;
3514
3515
3516    /* ===================================================================*/
3517    /* Various kinds of repeat; '{' is not necessarily a quantifier, but this
3518    has been tested above. */
3519
3520    case '{':
3521    if (!is_quantifier) goto NORMAL_CHAR;
3522    ptr = read_repeat_counts(ptr+1, &repeat_min, &repeat_max, errorcodeptr);
3523    if (*errorcodeptr != 0) goto FAILED;
3524    goto REPEAT;
3525
3526    case '*':
3527    repeat_min = 0;
3528    repeat_max = -1;
3529    goto REPEAT;
3530
3531    case '+':
3532    repeat_min = 1;
3533    repeat_max = -1;
3534    goto REPEAT;
3535
3536    case '?':
3537    repeat_min = 0;
3538    repeat_max = 1;
3539
3540    REPEAT:
3541    if (previous == NULL)
3542      {
3543      *errorcodeptr = ERR9;
3544      goto FAILED;
3545      }
3546
3547    if (repeat_min == 0)
3548      {
3549      firstbyte = zerofirstbyte;    /* Adjust for zero repeat */
3550      reqbyte = zeroreqbyte;        /* Ditto */
3551      }
3552
3553    /* Remember whether this is a variable length repeat */
3554
3555    reqvary = (repeat_min == repeat_max)? 0 : REQ_VARY;
3556
3557    op_type = 0;                    /* Default single-char op codes */
3558    possessive_quantifier = FALSE;  /* Default not possessive quantifier */
3559
3560    /* Save start of previous item, in case we have to move it up to make space
3561    for an inserted OP_ONCE for the additional '+' extension. */
3562
3563    tempcode = previous;
3564
3565    /* If the next character is '+', we have a possessive quantifier. This
3566    implies greediness, whatever the setting of the PCRE_UNGREEDY option.
3567    If the next character is '?' this is a minimizing repeat, by default,
3568    but if PCRE_UNGREEDY is set, it works the other way round. We change the
3569    repeat type to the non-default. */
3570
3571    if (ptr[1] == '+')
3572      {
3573      repeat_type = 0;                  /* Force greedy */
3574      possessive_quantifier = TRUE;
3575      ptr++;
3576      }
3577    else if (ptr[1] == '?')
3578      {
3579      repeat_type = greedy_non_default;
3580      ptr++;
3581      }
3582    else repeat_type = greedy_default;
3583
3584    /* If previous was a character match, abolish the item and generate a
3585    repeat item instead. If a char item has a minumum of more than one, ensure
3586    that it is set in reqbyte - it might not be if a sequence such as x{3} is
3587    the first thing in a branch because the x will have gone into firstbyte
3588    instead.  */
3589
3590    if (*previous == OP_CHAR || *previous == OP_CHARNC)
3591      {
3592      /* Deal with UTF-8 characters that take up more than one byte. It's
3593      easier to write this out separately than try to macrify it. Use c to
3594      hold the length of the character in bytes, plus 0x80 to flag that it's a
3595      length rather than a small character. */
3596
3597#ifdef SUPPORT_UTF8
3598      if (utf8 && (code[-1] & 0x80) != 0)
3599        {
3600        uschar *lastchar = code - 1;
3601        while((*lastchar & 0xc0) == 0x80) lastchar--;
3602        c = code - lastchar;            /* Length of UTF-8 character */
3603        memcpy(utf8_char, lastchar, c); /* Save the char */
3604        c |= 0x80;                      /* Flag c as a length */
3605        }
3606      else
3607#endif
3608
3609      /* Handle the case of a single byte - either with no UTF8 support, or
3610      with UTF-8 disabled, or for a UTF-8 character < 128. */
3611
3612        {
3613        c = code[-1];
3614        if (repeat_min > 1) reqbyte = c | req_caseopt | cd->req_varyopt;
3615        }
3616
3617      /* If the repetition is unlimited, it pays to see if the next thing on
3618      the line is something that cannot possibly match this character. If so,
3619      automatically possessifying this item gains some performance in the case
3620      where the match fails. */
3621
3622      if (!possessive_quantifier &&
3623          repeat_max < 0 &&
3624          check_auto_possessive(*previous, c, utf8, utf8_char, ptr + 1,
3625            options, cd))
3626        {
3627        repeat_type = 0;    /* Force greedy */
3628        possessive_quantifier = TRUE;
3629        }
3630
3631      goto OUTPUT_SINGLE_REPEAT;   /* Code shared with single character types */
3632      }
3633
3634    /* If previous was a single negated character ([^a] or similar), we use
3635    one of the special opcodes, replacing it. The code is shared with single-
3636    character repeats by setting opt_type to add a suitable offset into
3637    repeat_type. We can also test for auto-possessification. OP_NOT is
3638    currently used only for single-byte chars. */
3639
3640    else if (*previous == OP_NOT)
3641      {
3642      op_type = OP_NOTSTAR - OP_STAR;  /* Use "not" opcodes */
3643      c = previous[1];
3644      if (!possessive_quantifier &&
3645          repeat_max < 0 &&
3646          check_auto_possessive(OP_NOT, c, utf8, NULL, ptr + 1, options, cd))
3647        {
3648        repeat_type = 0;    /* Force greedy */
3649        possessive_quantifier = TRUE;
3650        }
3651      goto OUTPUT_SINGLE_REPEAT;
3652      }
3653
3654    /* If previous was a character type match (\d or similar), abolish it and
3655    create a suitable repeat item. The code is shared with single-character
3656    repeats by setting op_type to add a suitable offset into repeat_type. Note
3657    the the Unicode property types will be present only when SUPPORT_UCP is
3658    defined, but we don't wrap the little bits of code here because it just
3659    makes it horribly messy. */
3660
3661    else if (*previous < OP_EODN)
3662      {
3663      uschar *oldcode;
3664      int prop_type, prop_value;
3665      op_type = OP_TYPESTAR - OP_STAR;  /* Use type opcodes */
3666      c = *previous;
3667
3668      if (!possessive_quantifier &&
3669          repeat_max < 0 &&
3670          check_auto_possessive(c, 0, utf8, NULL, ptr + 1, options, cd))
3671        {
3672        repeat_type = 0;    /* Force greedy */
3673        possessive_quantifier = TRUE;
3674        }
3675
3676      OUTPUT_SINGLE_REPEAT:
3677      if (*previous == OP_PROP || *previous == OP_NOTPROP)
3678        {
3679        prop_type = previous[1];
3680        prop_value = previous[2];
3681        }
3682      else prop_type = prop_value = -1;
3683
3684      oldcode = code;
3685      code = previous;                  /* Usually overwrite previous item */
3686
3687      /* If the maximum is zero then the minimum must also be zero; Perl allows
3688      this case, so we do too - by simply omitting the item altogether. */
3689
3690      if (repeat_max == 0) goto END_REPEAT;
3691
3692      /* All real repeats make it impossible to handle partial matching (maybe
3693      one day we will be able to remove this restriction). */
3694
3695      if (repeat_max != 1) cd->external_flags |= PCRE_NOPARTIAL;
3696
3697      /* Combine the op_type with the repeat_type */
3698
3699      repeat_type += op_type;
3700
3701      /* A minimum of zero is handled either as the special case * or ?, or as
3702      an UPTO, with the maximum given. */
3703
3704      if (repeat_min == 0)
3705        {
3706        if (repeat_max == -1) *code++ = OP_STAR + repeat_type;
3707          else if (repeat_max == 1) *code++ = OP_QUERY + repeat_type;
3708        else
3709          {
3710          *code++ = OP_UPTO + repeat_type;
3711          PUT2INC(code, 0, repeat_max);
3712          }
3713        }
3714
3715      /* A repeat minimum of 1 is optimized into some special cases. If the
3716      maximum is unlimited, we use OP_PLUS. Otherwise, the original item is
3717      left in place and, if the maximum is greater than 1, we use OP_UPTO with
3718      one less than the maximum. */
3719
3720      else if (repeat_min == 1)
3721        {
3722        if (repeat_max == -1)
3723          *code++ = OP_PLUS + repeat_type;
3724        else
3725          {
3726          code = oldcode;                 /* leave previous item in place */
3727          if (repeat_max == 1) goto END_REPEAT;
3728          *code++ = OP_UPTO + repeat_type;
3729          PUT2INC(code, 0, repeat_max - 1);
3730          }
3731        }
3732
3733      /* The case {n,n} is just an EXACT, while the general case {n,m} is
3734      handled as an EXACT followed by an UPTO. */
3735
3736      else
3737        {
3738        *code++ = OP_EXACT + op_type;  /* NB EXACT doesn't have repeat_type */
3739        PUT2INC(code, 0, repeat_min);
3740
3741        /* If the maximum is unlimited, insert an OP_STAR. Before doing so,
3742        we have to insert the character for the previous code. For a repeated
3743        Unicode property match, there are two extra bytes that define the
3744        required property. In UTF-8 mode, long characters have their length in
3745        c, with the 0x80 bit as a flag. */
3746
3747        if (repeat_max < 0)
3748          {
3749#ifdef SUPPORT_UTF8
3750          if (utf8 && c >= 128)
3751            {
3752            memcpy(code, utf8_char, c & 7);
3753            code += c & 7;
3754            }
3755          else
3756#endif
3757            {
3758            *code++ = c;
3759            if (prop_type >= 0)
3760              {
3761              *code++ = prop_type;
3762              *code++ = prop_value;
3763              }
3764            }
3765          *code++ = OP_STAR + repeat_type;
3766          }
3767
3768        /* Else insert an UPTO if the max is greater than the min, again
3769        preceded by the character, for the previously inserted code. If the
3770        UPTO is just for 1 instance, we can use QUERY instead. */
3771
3772        else if (repeat_max != repeat_min)
3773          {
3774#ifdef SUPPORT_UTF8
3775          if (utf8 && c >= 128)
3776            {
3777            memcpy(code, utf8_char, c & 7);
3778            code += c & 7;
3779            }
3780          else
3781#endif
3782          *code++ = c;
3783          if (prop_type >= 0)
3784            {
3785            *code++ = prop_type;
3786            *code++ = prop_value;
3787            }
3788          repeat_max -= repeat_min;
3789
3790          if (repeat_max == 1)
3791            {
3792            *code++ = OP_QUERY + repeat_type;
3793            }
3794          else
3795            {
3796            *code++ = OP_UPTO + repeat_type;
3797            PUT2INC(code, 0, repeat_max);
3798            }
3799          }
3800        }
3801
3802      /* The character or character type itself comes last in all cases. */
3803
3804#ifdef SUPPORT_UTF8
3805      if (utf8 && c >= 128)
3806        {
3807        memcpy(code, utf8_char, c & 7);
3808        code += c & 7;
3809        }
3810      else
3811#endif
3812      *code++ = c;
3813
3814      /* For a repeated Unicode property match, there are two extra bytes that
3815      define the required property. */
3816
3817#ifdef SUPPORT_UCP
3818      if (prop_type >= 0)
3819        {
3820        *code++ = prop_type;
3821        *code++ = prop_value;
3822        }
3823#endif
3824      }
3825
3826    /* If previous was a character class or a back reference, we put the repeat
3827    stuff after it, but just skip the item if the repeat was {0,0}. */
3828
3829    else if (*previous == OP_CLASS ||
3830             *previous == OP_NCLASS ||
3831#ifdef SUPPORT_UTF8
3832             *previous == OP_XCLASS ||
3833#endif
3834             *previous == OP_REF)
3835      {
3836      if (repeat_max == 0)
3837        {
3838        code = previous;
3839        goto END_REPEAT;
3840        }
3841
3842      /* All real repeats make it impossible to handle partial matching (maybe
3843      one day we will be able to remove this restriction). */
3844
3845      if (repeat_max != 1) cd->external_flags |= PCRE_NOPARTIAL;
3846
3847      if (repeat_min == 0 && repeat_max == -1)
3848        *code++ = OP_CRSTAR + repeat_type;
3849      else if (repeat_min == 1 && repeat_max == -1)
3850        *code++ = OP_CRPLUS + repeat_type;
3851      else if (repeat_min == 0 && repeat_max == 1)
3852        *code++ = OP_CRQUERY + repeat_type;
3853      else
3854        {
3855        *code++ = OP_CRRANGE + repeat_type;
3856        PUT2INC(code, 0, repeat_min);
3857        if (repeat_max == -1) repeat_max = 0;  /* 2-byte encoding for max */
3858        PUT2INC(code, 0, repeat_max);
3859        }
3860      }
3861
3862    /* If previous was a bracket group, we may have to replicate it in certain
3863    cases. */
3864
3865    else if (*previous == OP_BRA  || *previous == OP_CBRA ||
3866             *previous == OP_ONCE || *previous == OP_COND)
3867      {
3868      register int i;
3869      int ketoffset = 0;
3870      int len = code - previous;
3871      uschar *bralink = NULL;
3872
3873      /* Repeating a DEFINE group is pointless */
3874
3875      if (*previous == OP_COND && previous[LINK_SIZE+1] == OP_DEF)
3876        {
3877        *errorcodeptr = ERR55;
3878        goto FAILED;
3879        }
3880
3881      /* If the maximum repeat count is unlimited, find the end of the bracket
3882      by scanning through from the start, and compute the offset back to it
3883      from the current code pointer. There may be an OP_OPT setting following
3884      the final KET, so we can't find the end just by going back from the code
3885      pointer. */
3886
3887      if (repeat_max == -1)
3888        {
3889        register uschar *ket = previous;
3890        do ket += GET(ket, 1); while (*ket != OP_KET);
3891        ketoffset = code - ket;
3892        }
3893
3894      /* The case of a zero minimum is special because of the need to stick
3895      OP_BRAZERO in front of it, and because the group appears once in the
3896      data, whereas in other cases it appears the minimum number of times. For
3897      this reason, it is simplest to treat this case separately, as otherwise
3898      the code gets far too messy. There are several special subcases when the
3899      minimum is zero. */
3900
3901      if (repeat_min == 0)
3902        {
3903        /* If the maximum is also zero, we used to just omit the group from the
3904        output altogether, like this:
3905
3906        ** if (repeat_max == 0)
3907        **   {
3908        **   code = previous;
3909        **   goto END_REPEAT;
3910        **   }
3911
3912        However, that fails when a group is referenced as a subroutine from
3913        elsewhere in the pattern, so now we stick in OP_SKIPZERO in front of it
3914        so that it is skipped on execution. As we don't have a list of which
3915        groups are referenced, we cannot do this selectively.
3916
3917        If the maximum is 1 or unlimited, we just have to stick in the BRAZERO
3918        and do no more at this point. However, we do need to adjust any
3919        OP_RECURSE calls inside the group that refer to the group itself or any
3920        internal or forward referenced group, because the offset is from the
3921        start of the whole regex. Temporarily terminate the pattern while doing
3922        this. */
3923
3924        if (repeat_max <= 1)    /* Covers 0, 1, and unlimited */
3925          {
3926          *code = OP_END;
3927          adjust_recurse(previous, 1, utf8, cd, save_hwm);
3928          memmove(previous+1, previous, len);
3929          code++;
3930          if (repeat_max == 0)
3931            {
3932            *previous++ = OP_SKIPZERO;
3933            goto END_REPEAT;
3934            }
3935          *previous++ = OP_BRAZERO + repeat_type;
3936          }
3937
3938        /* If the maximum is greater than 1 and limited, we have to replicate
3939        in a nested fashion, sticking OP_BRAZERO before each set of brackets.
3940        The first one has to be handled carefully because it's the original
3941        copy, which has to be moved up. The remainder can be handled by code
3942        that is common with the non-zero minimum case below. We have to
3943        adjust the value or repeat_max, since one less copy is required. Once
3944        again, we may have to adjust any OP_RECURSE calls inside the group. */
3945
3946        else
3947          {
3948          int offset;
3949          *code = OP_END;
3950          adjust_recurse(previous, 2 + LINK_SIZE, utf8, cd, save_hwm);
3951          memmove(previous + 2 + LINK_SIZE, previous, len);
3952          code += 2 + LINK_SIZE;
3953          *previous++ = OP_BRAZERO + repeat_type;
3954          *previous++ = OP_BRA;
3955
3956          /* We chain together the bracket offset fields that have to be
3957          filled in later when the ends of the brackets are reached. */
3958
3959          offset = (bralink == NULL)? 0 : previous - bralink;
3960          bralink = previous;
3961          PUTINC(previous, 0, offset);
3962          }
3963
3964        repeat_max--;
3965        }
3966
3967      /* If the minimum is greater than zero, replicate the group as many
3968      times as necessary, and adjust the maximum to the number of subsequent
3969      copies that we need. If we set a first char from the group, and didn't
3970      set a required char, copy the latter from the former. If there are any
3971      forward reference subroutine calls in the group, there will be entries on
3972      the workspace list; replicate these with an appropriate increment. */
3973
3974      else
3975        {
3976        if (repeat_min > 1)
3977          {
3978          /* In the pre-compile phase, we don't actually do the replication. We
3979          just adjust the length as if we had. Do some paranoid checks for
3980          potential integer overflow. */
3981
3982          if (lengthptr != NULL)
3983            {
3984            int delta = (repeat_min - 1)*length_prevgroup;
3985            if ((double)(repeat_min - 1)*(double)length_prevgroup >
3986                                                            (double)INT_MAX ||
3987                OFLOW_MAX - *lengthptr < delta)
3988              {
3989              *errorcodeptr = ERR20;
3990              goto FAILED;
3991              }
3992            *lengthptr += delta;
3993            }
3994
3995          /* This is compiling for real */
3996
3997          else
3998            {
3999            if (groupsetfirstbyte && reqbyte < 0) reqbyte = firstbyte;
4000            for (i = 1; i < repeat_min; i++)
4001              {
4002              uschar *hc;
4003              uschar *this_hwm = cd->hwm;
4004              memcpy(code, previous, len);
4005              for (hc = save_hwm; hc < this_hwm; hc += LINK_SIZE)
4006                {
4007                PUT(cd->hwm, 0, GET(hc, 0) + len);
4008                cd->hwm += LINK_SIZE;
4009                }
4010              save_hwm = this_hwm;
4011              code += len;
4012              }
4013            }
4014          }
4015
4016        if (repeat_max > 0) repeat_max -= repeat_min;
4017        }
4018
4019      /* This code is common to both the zero and non-zero minimum cases. If
4020      the maximum is limited, it replicates the group in a nested fashion,
4021      remembering the bracket starts on a stack. In the case of a zero minimum,
4022      the first one was set up above. In all cases the repeat_max now specifies
4023      the number of additional copies needed. Again, we must remember to
4024      replicate entries on the forward reference list. */
4025
4026      if (repeat_max >= 0)
4027        {
4028        /* In the pre-compile phase, we don't actually do the replication. We
4029        just adjust the length as if we had. For each repetition we must add 1
4030        to the length for BRAZERO and for all but the last repetition we must
4031        add 2 + 2*LINKSIZE to allow for the nesting that occurs. Do some
4032        paranoid checks to avoid integer overflow. */
4033
4034        if (lengthptr != NULL && repeat_max > 0)
4035          {
4036          int delta = repeat_max * (length_prevgroup + 1 + 2 + 2*LINK_SIZE) -
4037                      2 - 2*LINK_SIZE;   /* Last one doesn't nest */
4038          if ((double)repeat_max *
4039                (double)(length_prevgroup + 1 + 2 + 2*LINK_SIZE)
4040                  > (double)INT_MAX ||
4041              OFLOW_MAX - *lengthptr < delta)
4042            {
4043            *errorcodeptr = ERR20;
4044            goto FAILED;
4045            }
4046          *lengthptr += delta;
4047          }
4048
4049        /* This is compiling for real */
4050
4051        else for (i = repeat_max - 1; i >= 0; i--)
4052          {
4053          uschar *hc;
4054          uschar *this_hwm = cd->hwm;
4055
4056          *code++ = OP_BRAZERO + repeat_type;
4057
4058          /* All but the final copy start a new nesting, maintaining the
4059          chain of brackets outstanding. */
4060
4061          if (i != 0)
4062            {
4063            int offset;
4064            *code++ = OP_BRA;
4065            offset = (bralink == NULL)? 0 : code - bralink;
4066            bralink = code;
4067            PUTINC(code, 0, offset);
4068            }
4069
4070          memcpy(code, previous, len);
4071          for (hc = save_hwm; hc < this_hwm; hc += LINK_SIZE)
4072            {
4073            PUT(cd->hwm, 0, GET(hc, 0) + len + ((i != 0)? 2+LINK_SIZE : 1));
4074            cd->hwm += LINK_SIZE;
4075            }
4076          save_hwm = this_hwm;
4077          code += len;
4078          }
4079
4080        /* Now chain through the pending brackets, and fill in their length
4081        fields (which are holding the chain links pro tem). */
4082
4083        while (bralink != NULL)
4084          {
4085          int oldlinkoffset;
4086          int offset = code - bralink + 1;
4087          uschar *bra = code - offset;
4088          oldlinkoffset = GET(bra, 1);
4089          bralink = (oldlinkoffset == 0)? NULL : bralink - oldlinkoffset;
4090          *code++ = OP_KET;
4091          PUTINC(code, 0, offset);
4092          PUT(bra, 1, offset);
4093          }
4094        }
4095
4096      /* If the maximum is unlimited, set a repeater in the final copy. We
4097      can't just offset backwards from the current code point, because we
4098      don't know if there's been an options resetting after the ket. The
4099      correct offset was computed above.
4100
4101      Then, when we are doing the actual compile phase, check to see whether
4102      this group is a non-atomic one that could match an empty string. If so,
4103      convert the initial operator to the S form (e.g. OP_BRA -> OP_SBRA) so
4104      that runtime checking can be done. [This check is also applied to
4105      atomic groups at runtime, but in a different way.] */
4106
4107      else
4108        {
4109        uschar *ketcode = code - ketoffset;
4110        uschar *bracode = ketcode - GET(ketcode, 1);
4111        *ketcode = OP_KETRMAX + repeat_type;
4112        if (lengthptr == NULL && *bracode != OP_ONCE)
4113          {
4114          uschar *scode = bracode;
4115          do
4116            {
4117            if (could_be_empty_branch(scode, ketcode, utf8))
4118              {
4119              *bracode += OP_SBRA - OP_BRA;
4120              break;
4121              }
4122            scode += GET(scode, 1);
4123            }
4124          while (*scode == OP_ALT);
4125          }
4126        }
4127      }
4128
4129    /* If previous is OP_FAIL, it was generated by an empty class [] in
4130    JavaScript mode. The other ways in which OP_FAIL can be generated, that is
4131    by (*FAIL) or (?!) set previous to NULL, which gives a "nothing to repeat"
4132    error above. We can just ignore the repeat in JS case. */
4133
4134    else if (*previous == OP_FAIL) goto END_REPEAT;
4135
4136    /* Else there's some kind of shambles */
4137
4138    else
4139      {
4140      *errorcodeptr = ERR11;
4141      goto FAILED;
4142      }
4143
4144    /* If the character following a repeat is '+', or if certain optimization
4145    tests above succeeded, possessive_quantifier is TRUE. For some of the
4146    simpler opcodes, there is an special alternative opcode for this. For
4147    anything else, we wrap the entire repeated item inside OP_ONCE brackets.
4148    The '+' notation is just syntactic sugar, taken from Sun's Java package,
4149    but the special opcodes can optimize it a bit. The repeated item starts at
4150    tempcode, not at previous, which might be the first part of a string whose
4151    (former) last char we repeated.
4152
4153    Possessifying an 'exact' quantifier has no effect, so we can ignore it. But
4154    an 'upto' may follow. We skip over an 'exact' item, and then test the
4155    length of what remains before proceeding. */
4156
4157    if (possessive_quantifier)
4158      {
4159      int len;
4160      if (*tempcode == OP_EXACT || *tempcode == OP_TYPEEXACT ||
4161          *tempcode == OP_NOTEXACT)
4162        tempcode += _pcre_OP_lengths[*tempcode] +
4163          ((*tempcode == OP_TYPEEXACT &&
4164             (tempcode[3] == OP_PROP || tempcode[3] == OP_NOTPROP))? 2:0);
4165      len = code - tempcode;
4166      if (len > 0) switch (*tempcode)
4167        {
4168        case OP_STAR:  *tempcode = OP_POSSTAR; break;
4169        case OP_PLUS:  *tempcode = OP_POSPLUS; break;
4170        case OP_QUERY: *tempcode = OP_POSQUERY; break;
4171        case OP_UPTO:  *tempcode = OP_POSUPTO; break;
4172
4173        case OP_TYPESTAR:  *tempcode = OP_TYPEPOSSTAR; break;
4174        case OP_TYPEPLUS:  *tempcode = OP_TYPEPOSPLUS; break;
4175        case OP_TYPEQUERY: *tempcode = OP_TYPEPOSQUERY; break;
4176        case OP_TYPEUPTO:  *tempcode = OP_TYPEPOSUPTO; break;
4177
4178        case OP_NOTSTAR:  *tempcode = OP_NOTPOSSTAR; break;
4179        case OP_NOTPLUS:  *tempcode = OP_NOTPOSPLUS; break;
4180        case OP_NOTQUERY: *tempcode = OP_NOTPOSQUERY; break;
4181        case OP_NOTUPTO:  *tempcode = OP_NOTPOSUPTO; break;
4182
4183        default:
4184        memmove(tempcode + 1+LINK_SIZE, tempcode, len);
4185        code += 1 + LINK_SIZE;
4186        len += 1 + LINK_SIZE;
4187        tempcode[0] = OP_ONCE;
4188        *code++ = OP_KET;
4189        PUTINC(code, 0, len);
4190        PUT(tempcode, 1, len);
4191        break;
4192        }
4193      }
4194
4195    /* In all case we no longer have a previous item. We also set the
4196    "follows varying string" flag for subsequently encountered reqbytes if
4197    it isn't already set and we have just passed a varying length item. */
4198
4199    END_REPEAT:
4200    previous = NULL;
4201    cd->req_varyopt |= reqvary;
4202    break;
4203
4204
4205    /* ===================================================================*/
4206    /* Start of nested parenthesized sub-expression, or comment or lookahead or
4207    lookbehind or option setting or condition or all the other extended
4208    parenthesis forms.  */
4209
4210    case '(':
4211    newoptions = options;
4212    skipbytes = 0;
4213    bravalue = OP_CBRA;
4214    save_hwm = cd->hwm;
4215    reset_bracount = FALSE;
4216
4217    /* First deal with various "verbs" that can be introduced by '*'. */
4218
4219    if (*(++ptr) == '*' && (cd->ctypes[ptr[1]] & ctype_letter) != 0)
4220      {
4221      int i, namelen;
4222      const char *vn = verbnames;
4223      const uschar *name = ++ptr;
4224      previous = NULL;
4225      while ((cd->ctypes[*++ptr] & ctype_letter) != 0) {};
4226      if (*ptr == ':')
4227        {
4228        *errorcodeptr = ERR59;   /* Not supported */
4229        goto FAILED;
4230        }
4231      if (*ptr != ')')
4232        {
4233        *errorcodeptr = ERR60;
4234        goto FAILED;
4235        }
4236      namelen = ptr - name;
4237      for (i = 0; i < verbcount; i++)
4238        {
4239        if (namelen == verbs[i].len &&
4240            strncmp((char *)name, vn, namelen) == 0)
4241          {
4242          *code = verbs[i].op;
4243          if (*code++ == OP_ACCEPT) cd->had_accept = TRUE;
4244          break;
4245          }
4246        vn += verbs[i].len + 1;
4247        }
4248      if (i < verbcount) continue;
4249      *errorcodeptr = ERR60;
4250      goto FAILED;
4251      }
4252
4253    /* Deal with the extended parentheses; all are introduced by '?', and the
4254    appearance of any of them means that this is not a capturing group. */
4255
4256    else if (*ptr == '?')
4257      {
4258      int i, set, unset, namelen;
4259      int *optset;
4260      const uschar *name;
4261      uschar *slot;
4262
4263      switch (*(++ptr))
4264        {
4265        case '#':                 /* Comment; skip to ket */
4266        ptr++;
4267        while (*ptr != 0 && *ptr != ')') ptr++;
4268        if (*ptr == 0)
4269          {
4270          *errorcodeptr = ERR18;
4271          goto FAILED;
4272          }
4273        continue;
4274
4275
4276        /* ------------------------------------------------------------ */
4277        case '|':                 /* Reset capture count for each branch */
4278        reset_bracount = TRUE;
4279        /* Fall through */
4280
4281        /* ------------------------------------------------------------ */
4282        case ':':                 /* Non-capturing bracket */
4283        bravalue = OP_BRA;
4284        ptr++;
4285        break;
4286
4287
4288        /* ------------------------------------------------------------ */
4289        case '(':
4290        bravalue = OP_COND;       /* Conditional group */
4291
4292        /* A condition can be an assertion, a number (referring to a numbered
4293        group), a name (referring to a named group), or 'R', referring to
4294        recursion. R<digits> and R&name are also permitted for recursion tests.
4295
4296        There are several syntaxes for testing a named group: (?(name)) is used
4297        by Python; Perl 5.10 onwards uses (?(<name>) or (?('name')).
4298
4299        There are two unfortunate ambiguities, caused by history. (a) 'R' can
4300        be the recursive thing or the name 'R' (and similarly for 'R' followed
4301        by digits), and (b) a number could be a name that consists of digits.
4302        In both cases, we look for a name first; if not found, we try the other
4303        cases. */
4304
4305        /* For conditions that are assertions, check the syntax, and then exit
4306        the switch. This will take control down to where bracketed groups,
4307        including assertions, are processed. */
4308
4309        if (ptr[1] == '?' && (ptr[2] == '=' || ptr[2] == '!' || ptr[2] == '<'))
4310          break;
4311
4312        /* Most other conditions use OP_CREF (a couple change to OP_RREF
4313        below), and all need to skip 3 bytes at the start of the group. */
4314
4315        code[1+LINK_SIZE] = OP_CREF;
4316        skipbytes = 3;
4317        refsign = -1;
4318
4319        /* Check for a test for recursion in a named group. */
4320
4321        if (ptr[1] == 'R' && ptr[2] == '&')
4322          {
4323          terminator = -1;
4324          ptr += 2;
4325          code[1+LINK_SIZE] = OP_RREF;    /* Change the type of test */
4326          }
4327
4328        /* Check for a test for a named group's having been set, using the Perl
4329        syntax (?(<name>) or (?('name') */
4330
4331        else if (ptr[1] == '<')
4332          {
4333          terminator = '>';
4334          ptr++;
4335          }
4336        else if (ptr[1] == '\'')
4337          {
4338          terminator = '\'';
4339          ptr++;
4340          }
4341        else
4342          {
4343          terminator = 0;
4344          if (ptr[1] == '-' || ptr[1] == '+') refsign = *(++ptr);
4345          }
4346
4347        /* We now expect to read a name; any thing else is an error */
4348
4349        if ((cd->ctypes[ptr[1]] & ctype_word) == 0)
4350          {
4351          ptr += 1;  /* To get the right offset */
4352          *errorcodeptr = ERR28;
4353          goto FAILED;
4354          }
4355
4356        /* Read the name, but also get it as a number if it's all digits */
4357
4358        recno = 0;
4359        name = ++ptr;
4360        while ((cd->ctypes[*ptr] & ctype_word) != 0)
4361          {
4362          if (recno >= 0)
4363            recno = ((digitab[*ptr] & ctype_digit) != 0)?
4364              recno * 10 + *ptr - '0' : -1;
4365          ptr++;
4366          }
4367        namelen = ptr - name;
4368
4369        if ((terminator > 0 && *ptr++ != terminator) || *ptr++ != ')')
4370          {
4371          ptr--;      /* Error offset */
4372          *errorcodeptr = ERR26;
4373          goto FAILED;
4374          }
4375
4376        /* Do no further checking in the pre-compile phase. */
4377
4378        if (lengthptr != NULL) break;
4379
4380        /* In the real compile we do the work of looking for the actual
4381        reference. If the string started with "+" or "-" we require the rest to
4382        be digits, in which case recno will be set. */
4383
4384        if (refsign > 0)
4385          {
4386          if (recno <= 0)
4387            {
4388            *errorcodeptr = ERR58;
4389            goto FAILED;
4390            }
4391          recno = (refsign == '-')?
4392            cd->bracount - recno + 1 : recno +cd->bracount;
4393          if (recno <= 0 || recno > cd->final_bracount)
4394            {
4395            *errorcodeptr = ERR15;
4396            goto FAILED;
4397            }
4398          PUT2(code, 2+LINK_SIZE, recno);
4399          break;
4400          }
4401
4402        /* Otherwise (did not start with "+" or "-"), start by looking for the
4403        name. */
4404
4405        slot = cd->name_table;
4406        for (i = 0; i < cd->names_found; i++)
4407          {
4408          if (strncmp((char *)name, (char *)slot+2, namelen) == 0) break;
4409          slot += cd->name_entry_size;
4410          }
4411
4412        /* Found a previous named subpattern */
4413
4414        if (i < cd->names_found)
4415          {
4416          recno = GET2(slot, 0);
4417          PUT2(code, 2+LINK_SIZE, recno);
4418          }
4419
4420        /* Search the pattern for a forward reference */
4421
4422        else if ((i = find_parens(ptr, cd, name, namelen,
4423                        (options & PCRE_EXTENDED) != 0)) > 0)
4424          {
4425          PUT2(code, 2+LINK_SIZE, i);
4426          }
4427
4428        /* If terminator == 0 it means that the name followed directly after
4429        the opening parenthesis [e.g. (?(abc)...] and in this case there are
4430        some further alternatives to try. For the cases where terminator != 0
4431        [things like (?(<name>... or (?('name')... or (?(R&name)... ] we have
4432        now checked all the possibilities, so give an error. */
4433
4434        else if (terminator != 0)
4435          {
4436          *errorcodeptr = ERR15;
4437          goto FAILED;
4438          }
4439
4440        /* Check for (?(R) for recursion. Allow digits after R to specify a
4441        specific group number. */
4442
4443        else if (*name == 'R')
4444          {
4445          recno = 0;
4446          for (i = 1; i < namelen; i++)
4447            {
4448            if ((digitab[name[i]] & ctype_digit) == 0)
4449              {
4450              *errorcodeptr = ERR15;
4451              goto FAILED;
4452              }
4453            recno = recno * 10 + name[i] - '0';
4454            }
4455          if (recno == 0) recno = RREF_ANY;
4456          code[1+LINK_SIZE] = OP_RREF;      /* Change test type */
4457          PUT2(code, 2+LINK_SIZE, recno);
4458          }
4459
4460        /* Similarly, check for the (?(DEFINE) "condition", which is always
4461        false. */
4462
4463        else if (namelen == 6 && strncmp((char *)name, "DEFINE", 6) == 0)
4464          {
4465          code[1+LINK_SIZE] = OP_DEF;
4466          skipbytes = 1;
4467          }
4468
4469        /* Check for the "name" actually being a subpattern number. We are
4470        in the second pass here, so final_bracount is set. */
4471
4472        else if (recno > 0 && recno <= cd->final_bracount)
4473          {
4474          PUT2(code, 2+LINK_SIZE, recno);
4475          }
4476
4477        /* Either an unidentified subpattern, or a reference to (?(0) */
4478
4479        else
4480          {
4481          *errorcodeptr = (recno == 0)? ERR35: ERR15;
4482          goto FAILED;
4483          }
4484        break;
4485
4486
4487        /* ------------------------------------------------------------ */
4488        case '=':                 /* Positive lookahead */
4489        bravalue = OP_ASSERT;
4490        ptr++;
4491        break;
4492
4493
4494        /* ------------------------------------------------------------ */
4495        case '!':                 /* Negative lookahead */
4496        ptr++;
4497        if (*ptr == ')')          /* Optimize (?!) */
4498          {
4499          *code++ = OP_FAIL;
4500          previous = NULL;
4501          continue;
4502          }
4503        bravalue = OP_ASSERT_NOT;
4504        break;
4505
4506
4507        /* ------------------------------------------------------------ */
4508        case '<':                 /* Lookbehind or named define */
4509        switch (ptr[1])
4510          {
4511          case '=':               /* Positive lookbehind */
4512          bravalue = OP_ASSERTBACK;
4513          ptr += 2;
4514          break;
4515
4516          case '!':               /* Negative lookbehind */
4517          bravalue = OP_ASSERTBACK_NOT;
4518          ptr += 2;
4519          break;
4520
4521          default:                /* Could be name define, else bad */
4522          if ((cd->ctypes[ptr[1]] & ctype_word) != 0) goto DEFINE_NAME;
4523          ptr++;                  /* Correct offset for error */
4524          *errorcodeptr = ERR24;
4525          goto FAILED;
4526          }
4527        break;
4528
4529
4530        /* ------------------------------------------------------------ */
4531        case '>':                 /* One-time brackets */
4532        bravalue = OP_ONCE;
4533        ptr++;
4534        break;
4535
4536
4537        /* ------------------------------------------------------------ */
4538        case 'C':                 /* Callout - may be followed by digits; */
4539        previous_callout = code;  /* Save for later completion */
4540        after_manual_callout = 1; /* Skip one item before completing */
4541        *code++ = OP_CALLOUT;
4542          {
4543          int n = 0;
4544          while ((digitab[*(++ptr)] & ctype_digit) != 0)
4545            n = n * 10 + *ptr - '0';
4546          if (*ptr != ')')
4547            {
4548            *errorcodeptr = ERR39;
4549            goto FAILED;
4550            }
4551          if (n > 255)
4552            {
4553            *errorcodeptr = ERR38;
4554            goto FAILED;
4555            }
4556          *code++ = n;
4557          PUT(code, 0, ptr - cd->start_pattern + 1);  /* Pattern offset */
4558          PUT(code, LINK_SIZE, 0);                    /* Default length */
4559          code += 2 * LINK_SIZE;
4560          }
4561        previous = NULL;
4562        continue;
4563
4564
4565        /* ------------------------------------------------------------ */
4566        case 'P':                 /* Python-style named subpattern handling */
4567        if (*(++ptr) == '=' || *ptr == '>')  /* Reference or recursion */
4568          {
4569          is_recurse = *ptr == '>';
4570          terminator = ')';
4571          goto NAMED_REF_OR_RECURSE;
4572          }
4573        else if (*ptr != '<')    /* Test for Python-style definition */
4574          {
4575          *errorcodeptr = ERR41;
4576          goto FAILED;
4577          }
4578        /* Fall through to handle (?P< as (?< is handled */
4579
4580
4581        /* ------------------------------------------------------------ */
4582        DEFINE_NAME:    /* Come here from (?< handling */
4583        case '\'':
4584          {
4585          terminator = (*ptr == '<')? '>' : '\'';
4586          name = ++ptr;
4587
4588          while ((cd->ctypes[*ptr] & ctype_word) != 0) ptr++;
4589          namelen = ptr - name;
4590
4591          /* In the pre-compile phase, just do a syntax check. */
4592
4593          if (lengthptr != NULL)
4594            {
4595            if (*ptr != terminator)
4596              {
4597              *errorcodeptr = ERR42;
4598              goto FAILED;
4599              }
4600            if (cd->names_found >= MAX_NAME_COUNT)
4601              {
4602              *errorcodeptr = ERR49;
4603              goto FAILED;
4604              }
4605            if (namelen + 3 > cd->name_entry_size)
4606              {
4607              cd->name_entry_size = namelen + 3;
4608              if (namelen > MAX_NAME_SIZE)
4609                {
4610                *errorcodeptr = ERR48;
4611                goto FAILED;
4612                }
4613              }
4614            }
4615
4616          /* In the real compile, create the entry in the table */
4617
4618          else
4619            {
4620            slot = cd->name_table;
4621            for (i = 0; i < cd->names_found; i++)
4622              {
4623              int crc = memcmp(name, slot+2, namelen);
4624              if (crc == 0)
4625                {
4626                if (slot[2+namelen] == 0)
4627                  {
4628                  if ((options & PCRE_DUPNAMES) == 0)
4629                    {
4630                    *errorcodeptr = ERR43;
4631                    goto FAILED;
4632                    }
4633                  }
4634                else crc = -1;      /* Current name is substring */
4635                }
4636              if (crc < 0)
4637                {
4638                memmove(slot + cd->name_entry_size, slot,
4639                  (cd->names_found - i) * cd->name_entry_size);
4640                break;
4641                }
4642              slot += cd->name_entry_size;
4643              }
4644
4645            PUT2(slot, 0, cd->bracount + 1);
4646            memcpy(slot + 2, name, namelen);
4647            slot[2+namelen] = 0;
4648            }
4649          }
4650
4651        /* In both cases, count the number of names we've encountered. */
4652
4653        ptr++;                    /* Move past > or ' */
4654        cd->names_found++;
4655        goto NUMBERED_GROUP;
4656
4657
4658        /* ------------------------------------------------------------ */
4659        case '&':                 /* Perl recursion/subroutine syntax */
4660        terminator = ')';
4661        is_recurse = TRUE;
4662        /* Fall through */
4663
4664        /* We come here from the Python syntax above that handles both
4665        references (?P=name) and recursion (?P>name), as well as falling
4666        through from the Perl recursion syntax (?&name). We also come here from
4667        the Perl \k<name> or \k'name' back reference syntax and the \k{name}
4668        .NET syntax, and the Oniguruma \g<...> and \g'...' subroutine syntax. */
4669
4670        NAMED_REF_OR_RECURSE:
4671        name = ++ptr;
4672        while ((cd->ctypes[*ptr] & ctype_word) != 0) ptr++;
4673        namelen = ptr - name;
4674
4675        /* In the pre-compile phase, do a syntax check and set a dummy
4676        reference number. */
4677
4678        if (lengthptr != NULL)
4679          {
4680          if (namelen == 0)
4681            {
4682            *errorcodeptr = ERR62;
4683            goto FAILED;
4684            }
4685          if (*ptr != terminator)
4686            {
4687            *errorcodeptr = ERR42;
4688            goto FAILED;
4689            }
4690          if (namelen > MAX_NAME_SIZE)
4691            {
4692            *errorcodeptr = ERR48;
4693            goto FAILED;
4694            }
4695          recno = 0;
4696          }
4697
4698        /* In the real compile, seek the name in the table. We check the name
4699        first, and then check that we have reached the end of the name in the
4700        table. That way, if the name that is longer than any in the table,
4701        the comparison will fail without reading beyond the table entry. */
4702
4703        else
4704          {
4705          slot = cd->name_table;
4706          for (i = 0; i < cd->names_found; i++)
4707            {
4708            if (strncmp((char *)name, (char *)slot+2, namelen) == 0 &&
4709                slot[2+namelen] == 0)
4710              break;
4711            slot += cd->name_entry_size;
4712            }
4713
4714          if (i < cd->names_found)         /* Back reference */
4715            {
4716            recno = GET2(slot, 0);
4717            }
4718          else if ((recno =                /* Forward back reference */
4719                    find_parens(ptr, cd, name, namelen,
4720                      (options & PCRE_EXTENDED) != 0)) <= 0)
4721            {
4722            *errorcodeptr = ERR15;
4723            goto FAILED;
4724            }
4725          }
4726
4727        /* In both phases, we can now go to the code than handles numerical
4728        recursion or backreferences. */
4729
4730        if (is_recurse) goto HANDLE_RECURSION;
4731          else goto HANDLE_REFERENCE;
4732
4733
4734        /* ------------------------------------------------------------ */
4735        case 'R':                 /* Recursion */
4736        ptr++;                    /* Same as (?0)      */
4737        /* Fall through */
4738
4739
4740        /* ------------------------------------------------------------ */
4741        case '-': case '+':
4742        case '0': case '1': case '2': case '3': case '4':   /* Recursion or */
4743        case '5': case '6': case '7': case '8': case '9':   /* subroutine */
4744          {
4745          const uschar *called;
4746          terminator = ')';
4747
4748          /* Come here from the \g<...> and \g'...' code (Oniguruma
4749          compatibility). However, the syntax has been checked to ensure that
4750          the ... are a (signed) number, so that neither ERR63 nor ERR29 will
4751          be called on this path, nor with the jump to OTHER_CHAR_AFTER_QUERY
4752          ever be taken. */
4753
4754          HANDLE_NUMERICAL_RECURSION:
4755
4756          if ((refsign = *ptr) == '+')
4757            {
4758            ptr++;
4759            if ((digitab[*ptr] & ctype_digit) == 0)
4760              {
4761              *errorcodeptr = ERR63;
4762              goto FAILED;
4763              }
4764            }
4765          else if (refsign == '-')
4766            {
4767            if ((digitab[ptr[1]] & ctype_digit) == 0)
4768              goto OTHER_CHAR_AFTER_QUERY;
4769            ptr++;
4770            }
4771
4772          recno = 0;
4773          while((digitab[*ptr] & ctype_digit) != 0)
4774            recno = recno * 10 + *ptr++ - '0';
4775
4776          if (*ptr != terminator)
4777            {
4778            *errorcodeptr = ERR29;
4779            goto FAILED;
4780            }
4781
4782          if (refsign == '-')
4783            {
4784            if (recno == 0)
4785              {
4786              *errorcodeptr = ERR58;
4787              goto FAILED;
4788              }
4789            recno = cd->bracount - recno + 1;
4790            if (recno <= 0)
4791              {
4792              *errorcodeptr = ERR15;
4793              goto FAILED;
4794              }
4795            }
4796          else if (refsign == '+')
4797            {
4798            if (recno == 0)
4799              {
4800              *errorcodeptr = ERR58;
4801              goto FAILED;
4802              }
4803            recno += cd->bracount;
4804            }
4805
4806          /* Come here from code above that handles a named recursion */
4807
4808          HANDLE_RECURSION:
4809
4810          previous = code;
4811          called = cd->start_code;
4812
4813          /* When we are actually compiling, find the bracket that is being
4814          referenced. Temporarily end the regex in case it doesn't exist before
4815          this point. If we end up with a forward reference, first check that
4816          the bracket does occur later so we can give the error (and position)
4817          now. Then remember this forward reference in the workspace so it can
4818          be filled in at the end. */
4819
4820          if (lengthptr == NULL)
4821            {
4822            *code = OP_END;
4823            if (recno != 0) called = find_bracket(cd->start_code, utf8, recno);
4824
4825            /* Forward reference */
4826
4827            if (called == NULL)
4828              {
4829              if (find_parens(ptr, cd, NULL, recno,
4830                    (options & PCRE_EXTENDED) != 0) < 0)
4831                {
4832                *errorcodeptr = ERR15;
4833                goto FAILED;
4834                }
4835              called = cd->start_code + recno;
4836              PUTINC(cd->hwm, 0, code + 2 + LINK_SIZE - cd->start_code);
4837              }
4838
4839            /* If not a forward reference, and the subpattern is still open,
4840            this is a recursive call. We check to see if this is a left
4841            recursion that could loop for ever, and diagnose that case. */
4842
4843            else if (GET(called, 1) == 0 &&
4844                     could_be_empty(called, code, bcptr, utf8))
4845              {
4846              *errorcodeptr = ERR40;
4847              goto FAILED;
4848              }
4849            }
4850
4851          /* Insert the recursion/subroutine item, automatically wrapped inside
4852          "once" brackets. Set up a "previous group" length so that a
4853          subsequent quantifier will work. */
4854
4855          *code = OP_ONCE;
4856          PUT(code, 1, 2 + 2*LINK_SIZE);
4857          code += 1 + LINK_SIZE;
4858
4859          *code = OP_RECURSE;
4860          PUT(code, 1, called - cd->start_code);
4861          code += 1 + LINK_SIZE;
4862
4863          *code = OP_KET;
4864          PUT(code, 1, 2 + 2*LINK_SIZE);
4865          code += 1 + LINK_SIZE;
4866
4867          length_prevgroup = 3 + 3*LINK_SIZE;
4868          }
4869
4870        /* Can't determine a first byte now */
4871
4872        if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
4873        continue;
4874
4875
4876        /* ------------------------------------------------------------ */
4877        default:              /* Other characters: check option setting */
4878        OTHER_CHAR_AFTER_QUERY:
4879        set = unset = 0;
4880        optset = &set;
4881
4882        while (*ptr != ')' && *ptr != ':')
4883          {
4884          switch (*ptr++)
4885            {
4886            case '-': optset = &unset; break;
4887
4888            case 'J':    /* Record that it changed in the external options */
4889            *optset |= PCRE_DUPNAMES;
4890            cd->external_flags |= PCRE_JCHANGED;
4891            break;
4892
4893            case 'i': *optset |= PCRE_CASELESS; break;
4894            case 'm': *optset |= PCRE_MULTILINE; break;
4895            case 's': *optset |= PCRE_DOTALL; break;
4896            case 'x': *optset |= PCRE_EXTENDED; break;
4897            case 'U': *optset |= PCRE_UNGREEDY; break;
4898            case 'X': *optset |= PCRE_EXTRA; break;
4899
4900            default:  *errorcodeptr = ERR12;
4901                      ptr--;    /* Correct the offset */
4902                      goto FAILED;
4903            }
4904          }
4905
4906        /* Set up the changed option bits, but don't change anything yet. */
4907
4908        newoptions = (options | set) & (~unset);
4909
4910        /* If the options ended with ')' this is not the start of a nested
4911        group with option changes, so the options change at this level. If this
4912        item is right at the start of the pattern, the options can be
4913        abstracted and made external in the pre-compile phase, and ignored in
4914        the compile phase. This can be helpful when matching -- for instance in
4915        caseless checking of required bytes.
4916
4917        If the code pointer is not (cd->start_code + 1 + LINK_SIZE), we are
4918        definitely *not* at the start of the pattern because something has been
4919        compiled. In the pre-compile phase, however, the code pointer can have
4920        that value after the start, because it gets reset as code is discarded
4921        during the pre-compile. However, this can happen only at top level - if
4922        we are within parentheses, the starting BRA will still be present. At
4923        any parenthesis level, the length value can be used to test if anything
4924        has been compiled at that level. Thus, a test for both these conditions
4925        is necessary to ensure we correctly detect the start of the pattern in
4926        both phases.
4927
4928        If we are not at the pattern start, compile code to change the ims
4929        options if this setting actually changes any of them, and reset the
4930        greedy defaults and the case value for firstbyte and reqbyte. */
4931
4932        if (*ptr == ')')
4933          {
4934          if (code == cd->start_code + 1 + LINK_SIZE &&
4935               (lengthptr == NULL || *lengthptr == 2 + 2*LINK_SIZE))
4936            {
4937            cd->external_options = newoptions;
4938            }
4939         else
4940            {
4941            if ((options & PCRE_IMS) != (newoptions & PCRE_IMS))
4942              {
4943              *code++ = OP_OPT;
4944              *code++ = newoptions & PCRE_IMS;
4945              }
4946            greedy_default = ((newoptions & PCRE_UNGREEDY) != 0);
4947            greedy_non_default = greedy_default ^ 1;
4948            req_caseopt = ((newoptions & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;
4949            }
4950
4951          /* Change options at this level, and pass them back for use
4952          in subsequent branches. When not at the start of the pattern, this
4953          information is also necessary so that a resetting item can be
4954          compiled at the end of a group (if we are in a group). */
4955
4956          *optionsptr = options = newoptions;
4957          previous = NULL;       /* This item can't be repeated */
4958          continue;              /* It is complete */
4959          }
4960
4961        /* If the options ended with ':' we are heading into a nested group
4962        with possible change of options. Such groups are non-capturing and are
4963        not assertions of any kind. All we need to do is skip over the ':';
4964        the newoptions value is handled below. */
4965
4966        bravalue = OP_BRA;
4967        ptr++;
4968        }     /* End of switch for character following (? */
4969      }       /* End of (? handling */
4970
4971    /* Opening parenthesis not followed by '?'. If PCRE_NO_AUTO_CAPTURE is set,
4972    all unadorned brackets become non-capturing and behave like (?:...)
4973    brackets. */
4974
4975    else if ((options & PCRE_NO_AUTO_CAPTURE) != 0)
4976      {
4977      bravalue = OP_BRA;
4978      }
4979
4980    /* Else we have a capturing group. */
4981
4982    else
4983      {
4984      NUMBERED_GROUP:
4985      cd->bracount += 1;
4986      PUT2(code, 1+LINK_SIZE, cd->bracount);
4987      skipbytes = 2;
4988      }
4989
4990    /* Process nested bracketed regex. Assertions may not be repeated, but
4991    other kinds can be. All their opcodes are >= OP_ONCE. We copy code into a
4992    non-register variable in order to be able to pass its address because some
4993    compilers complain otherwise. Pass in a new setting for the ims options if
4994    they have changed. */
4995
4996    previous = (bravalue >= OP_ONCE)? code : NULL;
4997    *code = bravalue;
4998    tempcode = code;
4999    tempreqvary = cd->req_varyopt;     /* Save value before bracket */
5000    length_prevgroup = 0;              /* Initialize for pre-compile phase */
5001
5002    if (!compile_regex(
5003         newoptions,                   /* The complete new option state */
5004         options & PCRE_IMS,           /* The previous ims option state */
5005         &tempcode,                    /* Where to put code (updated) */
5006         &ptr,                         /* Input pointer (updated) */
5007         errorcodeptr,                 /* Where to put an error message */
5008         (bravalue == OP_ASSERTBACK ||
5009          bravalue == OP_ASSERTBACK_NOT), /* TRUE if back assert */
5010         reset_bracount,               /* True if (?| group */
5011         skipbytes,                    /* Skip over bracket number */
5012         &subfirstbyte,                /* For possible first char */
5013         &subreqbyte,                  /* For possible last char */
5014         bcptr,                        /* Current branch chain */
5015         cd,                           /* Tables block */
5016         (lengthptr == NULL)? NULL :   /* Actual compile phase */
5017           &length_prevgroup           /* Pre-compile phase */
5018         ))
5019      goto FAILED;
5020
5021    /* At the end of compiling, code is still pointing to the start of the
5022    group, while tempcode has been updated to point past the end of the group
5023    and any option resetting that may follow it. The pattern pointer (ptr)
5024    is on the bracket. */
5025
5026    /* If this is a conditional bracket, check that there are no more than
5027    two branches in the group, or just one if it's a DEFINE group. We do this
5028    in the real compile phase, not in the pre-pass, where the whole group may
5029    not be available. */
5030
5031    if (bravalue == OP_COND && lengthptr == NULL)
5032      {
5033      uschar *tc = code;
5034      int condcount = 0;
5035
5036      do {
5037         condcount++;
5038         tc += GET(tc,1);
5039         }
5040      while (*tc != OP_KET);
5041
5042      /* A DEFINE group is never obeyed inline (the "condition" is always
5043      false). It must have only one branch. */
5044
5045      if (code[LINK_SIZE+1] == OP_DEF)
5046        {
5047        if (condcount > 1)
5048          {
5049          *errorcodeptr = ERR54;
5050          goto FAILED;
5051          }
5052        bravalue = OP_DEF;   /* Just a flag to suppress char handling below */
5053        }
5054
5055      /* A "normal" conditional group. If there is just one branch, we must not
5056      make use of its firstbyte or reqbyte, because this is equivalent to an
5057      empty second branch. */
5058
5059      else
5060        {
5061        if (condcount > 2)
5062          {
5063          *errorcodeptr = ERR27;
5064          goto FAILED;
5065          }
5066        if (condcount == 1) subfirstbyte = subreqbyte = REQ_NONE;
5067        }
5068      }
5069
5070    /* Error if hit end of pattern */
5071
5072    if (*ptr != ')')
5073      {
5074      *errorcodeptr = ERR14;
5075      goto FAILED;
5076      }
5077
5078    /* In the pre-compile phase, update the length by the length of the group,
5079    less the brackets at either end. Then reduce the compiled code to just a
5080    set of non-capturing brackets so that it doesn't use much memory if it is
5081    duplicated by a quantifier.*/
5082
5083    if (lengthptr != NULL)
5084      {
5085      if (OFLOW_MAX - *lengthptr < length_prevgroup - 2 - 2*LINK_SIZE)
5086        {
5087        *errorcodeptr = ERR20;
5088        goto FAILED;
5089        }
5090      *lengthptr += length_prevgroup - 2 - 2*LINK_SIZE;
5091      *code++ = OP_BRA;
5092      PUTINC(code, 0, 1 + LINK_SIZE);
5093      *code++ = OP_KET;
5094      PUTINC(code, 0, 1 + LINK_SIZE);
5095      break;    /* No need to waste time with special character handling */
5096      }
5097
5098    /* Otherwise update the main code pointer to the end of the group. */
5099
5100    code = tempcode;
5101
5102    /* For a DEFINE group, required and first character settings are not
5103    relevant. */
5104
5105    if (bravalue == OP_DEF) break;
5106
5107    /* Handle updating of the required and first characters for other types of
5108    group. Update for normal brackets of all kinds, and conditions with two
5109    branches (see code above). If the bracket is followed by a quantifier with
5110    zero repeat, we have to back off. Hence the definition of zeroreqbyte and
5111    zerofirstbyte outside the main loop so that they can be accessed for the
5112    back off. */
5113
5114    zeroreqbyte = reqbyte;
5115    zerofirstbyte = firstbyte;
5116    groupsetfirstbyte = FALSE;
5117
5118    if (bravalue >= OP_ONCE)
5119      {
5120      /* If we have not yet set a firstbyte in this branch, take it from the
5121      subpattern, remembering that it was set here so that a repeat of more
5122      than one can replicate it as reqbyte if necessary. If the subpattern has
5123      no firstbyte, set "none" for the whole branch. In both cases, a zero
5124      repeat forces firstbyte to "none". */
5125
5126      if (firstbyte == REQ_UNSET)
5127        {
5128        if (subfirstbyte >= 0)
5129          {
5130          firstbyte = subfirstbyte;
5131          groupsetfirstbyte = TRUE;
5132          }
5133        else firstbyte = REQ_NONE;
5134        zerofirstbyte = REQ_NONE;
5135        }
5136
5137      /* If firstbyte was previously set, convert the subpattern's firstbyte
5138      into reqbyte if there wasn't one, using the vary flag that was in
5139      existence beforehand. */
5140
5141      else if (subfirstbyte >= 0 && subreqbyte < 0)
5142        subreqbyte = subfirstbyte | tempreqvary;
5143
5144      /* If the subpattern set a required byte (or set a first byte that isn't
5145      really the first byte - see above), set it. */
5146
5147      if (subreqbyte >= 0) reqbyte = subreqbyte;
5148      }
5149
5150    /* For a forward assertion, we take the reqbyte, if set. This can be
5151    helpful if the pattern that follows the assertion doesn't set a different
5152    char. For example, it's useful for /(?=abcde).+/. We can't set firstbyte
5153    for an assertion, however because it leads to incorrect effect for patterns
5154    such as /(?=a)a.+/ when the "real" "a" would then become a reqbyte instead
5155    of a firstbyte. This is overcome by a scan at the end if there's no
5156    firstbyte, looking for an asserted first char. */
5157
5158    else if (bravalue == OP_ASSERT && subreqbyte >= 0) reqbyte = subreqbyte;
5159    break;     /* End of processing '(' */
5160
5161
5162    /* ===================================================================*/
5163    /* Handle metasequences introduced by \. For ones like \d, the ESC_ values
5164    are arranged to be the negation of the corresponding OP_values. For the
5165    back references, the values are ESC_REF plus the reference number. Only
5166    back references and those types that consume a character may be repeated.
5167    We can test for values between ESC_b and ESC_Z for the latter; this may
5168    have to change if any new ones are ever created. */
5169
5170    case '\\':
5171    tempptr = ptr;
5172    c = check_escape(&ptr, errorcodeptr, cd->bracount, options, FALSE);
5173    if (*errorcodeptr != 0) goto FAILED;
5174
5175    if (c < 0)
5176      {
5177      if (-c == ESC_Q)            /* Handle start of quoted string */
5178        {
5179        if (ptr[1] == '\\' && ptr[2] == 'E') ptr += 2; /* avoid empty string */
5180          else inescq = TRUE;
5181        continue;
5182        }
5183
5184      if (-c == ESC_E) continue;  /* Perl ignores an orphan \E */
5185
5186      /* For metasequences that actually match a character, we disable the
5187      setting of a first character if it hasn't already been set. */
5188
5189      if (firstbyte == REQ_UNSET && -c > ESC_b && -c < ESC_Z)
5190        firstbyte = REQ_NONE;
5191
5192      /* Set values to reset to if this is followed by a zero repeat. */
5193
5194      zerofirstbyte = firstbyte;
5195      zeroreqbyte = reqbyte;
5196
5197      /* \g<name> or \g'name' is a subroutine call by name and \g<n> or \g'n'
5198      is a subroutine call by number (Oniguruma syntax). In fact, the value
5199      -ESC_g is returned only for these cases. So we don't need to check for <
5200      or ' if the value is -ESC_g. For the Perl syntax \g{n} the value is
5201      -ESC_REF+n, and for the Perl syntax \g{name} the result is -ESC_k (as
5202      that is a synonym for a named back reference). */
5203
5204      if (-c == ESC_g)
5205        {
5206        const uschar *p;
5207        save_hwm = cd->hwm;   /* Normally this is set when '(' is read */
5208        terminator = (*(++ptr) == '<')? '>' : '\'';
5209
5210        /* These two statements stop the compiler for warning about possibly
5211        unset variables caused by the jump to HANDLE_NUMERICAL_RECURSION. In
5212        fact, because we actually check for a number below, the paths that
5213        would actually be in error are never taken. */
5214
5215        skipbytes = 0;
5216        reset_bracount = FALSE;
5217
5218        /* Test for a name */
5219
5220        if (ptr[1] != '+' && ptr[1] != '-')
5221          {
5222          BOOL isnumber = TRUE;
5223          for (p = ptr + 1; *p != 0 && *p != terminator; p++)
5224            {
5225            if ((cd->ctypes[*p] & ctype_digit) == 0) isnumber = FALSE;
5226            if ((cd->ctypes[*p] & ctype_word) == 0) break;
5227            }
5228          if (*p != terminator)
5229            {
5230            *errorcodeptr = ERR57;
5231            break;
5232            }
5233          if (isnumber)
5234            {
5235            ptr++;
5236            goto HANDLE_NUMERICAL_RECURSION;
5237            }
5238          is_recurse = TRUE;
5239          goto NAMED_REF_OR_RECURSE;
5240          }
5241
5242        /* Test a signed number in angle brackets or quotes. */
5243
5244        p = ptr + 2;
5245        while ((digitab[*p] & ctype_digit) != 0) p++;
5246        if (*p != terminator)
5247          {
5248          *errorcodeptr = ERR57;
5249          break;
5250          }
5251        ptr++;
5252        goto HANDLE_NUMERICAL_RECURSION;
5253        }
5254
5255      /* \k<name> or \k'name' is a back reference by name (Perl syntax).
5256      We also support \k{name} (.NET syntax) */
5257
5258      if (-c == ESC_k && (ptr[1] == '<' || ptr[1] == '\'' || ptr[1] == '{'))
5259        {
5260        is_recurse = FALSE;
5261        terminator = (*(++ptr) == '<')? '>' : (*ptr == '\'')? '\'' : '}';
5262        goto NAMED_REF_OR_RECURSE;
5263        }
5264
5265      /* Back references are handled specially; must disable firstbyte if
5266      not set to cope with cases like (?=(\w+))\1: which would otherwise set
5267      ':' later. */
5268
5269      if (-c >= ESC_REF)
5270        {
5271        recno = -c - ESC_REF;
5272
5273        HANDLE_REFERENCE:    /* Come here from named backref handling */
5274        if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
5275        previous = code;
5276        *code++ = OP_REF;
5277        PUT2INC(code, 0, recno);
5278        cd->backref_map |= (recno < 32)? (1 << recno) : 1;
5279        if (recno > cd->top_backref) cd->top_backref = recno;
5280        }
5281
5282      /* So are Unicode property matches, if supported. */
5283
5284#ifdef SUPPORT_UCP
5285      else if (-c == ESC_P || -c == ESC_p)
5286        {
5287        BOOL negated;
5288        int pdata;
5289        int ptype = get_ucp(&ptr, &negated, &pdata, errorcodeptr);
5290        if (ptype < 0) goto FAILED;
5291        previous = code;
5292        *code++ = ((-c == ESC_p) != negated)? OP_PROP : OP_NOTPROP;
5293        *code++ = ptype;
5294        *code++ = pdata;
5295        }
5296#else
5297
5298      /* If Unicode properties are not supported, \X, \P, and \p are not
5299      allowed. */
5300
5301      else if (-c == ESC_X || -c == ESC_P || -c == ESC_p)
5302        {
5303        *errorcodeptr = ERR45;
5304        goto FAILED;
5305        }
5306#endif
5307
5308      /* For the rest (including \X when Unicode properties are supported), we
5309      can obtain the OP value by negating the escape value. */
5310
5311      else
5312        {
5313        previous = (-c > ESC_b && -c < ESC_Z)? code : NULL;
5314        *code++ = -c;
5315        }
5316      continue;
5317      }
5318
5319    /* We have a data character whose value is in c. In UTF-8 mode it may have
5320    a value > 127. We set its representation in the length/buffer, and then
5321    handle it as a data character. */
5322
5323#ifdef SUPPORT_UTF8
5324    if (utf8 && c > 127)
5325      mclength = _pcre_ord2utf8(c, mcbuffer);
5326    else
5327#endif
5328
5329     {
5330     mcbuffer[0] = c;
5331     mclength = 1;
5332     }
5333    goto ONE_CHAR;
5334
5335
5336    /* ===================================================================*/
5337    /* Handle a literal character. It is guaranteed not to be whitespace or #
5338    when the extended flag is set. If we are in UTF-8 mode, it may be a
5339    multi-byte literal character. */
5340
5341    default:
5342    NORMAL_CHAR:
5343    mclength = 1;
5344    mcbuffer[0] = c;
5345
5346#ifdef SUPPORT_UTF8
5347    if (utf8 && c >= 0xc0)
5348      {
5349      while ((ptr[1] & 0xc0) == 0x80)
5350        mcbuffer[mclength++] = *(++ptr);
5351      }
5352#endif
5353
5354    /* At this point we have the character's bytes in mcbuffer, and the length
5355    in mclength. When not in UTF-8 mode, the length is always 1. */
5356
5357    ONE_CHAR:
5358    previous = code;
5359    *code++ = ((options & PCRE_CASELESS) != 0)? OP_CHARNC : OP_CHAR;
5360    for (c = 0; c < mclength; c++) *code++ = mcbuffer[c];
5361
5362    /* Remember if \r or \n were seen */
5363
5364    if (mcbuffer[0] == '\r' || mcbuffer[0] == '\n')
5365      cd->external_flags |= PCRE_HASCRORLF;
5366
5367    /* Set the first and required bytes appropriately. If no previous first
5368    byte, set it from this character, but revert to none on a zero repeat.
5369    Otherwise, leave the firstbyte value alone, and don't change it on a zero
5370    repeat. */
5371
5372    if (firstbyte == REQ_UNSET)
5373      {
5374      zerofirstbyte = REQ_NONE;
5375      zeroreqbyte = reqbyte;
5376
5377      /* If the character is more than one byte long, we can set firstbyte
5378      only if it is not to be matched caselessly. */
5379
5380      if (mclength == 1 || req_caseopt == 0)
5381        {
5382        firstbyte = mcbuffer[0] | req_caseopt;
5383        if (mclength != 1) reqbyte = code[-1] | cd->req_varyopt;
5384        }
5385      else firstbyte = reqbyte = REQ_NONE;
5386      }
5387
5388    /* firstbyte was previously set; we can set reqbyte only the length is
5389    1 or the matching is caseful. */
5390
5391    else
5392      {
5393      zerofirstbyte = firstbyte;
5394      zeroreqbyte = reqbyte;
5395      if (mclength == 1 || req_caseopt == 0)
5396        reqbyte = code[-1] | req_caseopt | cd->req_varyopt;
5397      }
5398
5399    break;            /* End of literal character handling */
5400    }
5401  }                   /* end of big loop */
5402
5403
5404/* Control never reaches here by falling through, only by a goto for all the
5405error states. Pass back the position in the pattern so that it can be displayed
5406to the user for diagnosing the error. */
5407
5408FAILED:
5409*ptrptr = ptr;
5410return FALSE;
5411}
5412
5413
5414
5415
5416/*************************************************
5417*     Compile sequence of alternatives           *
5418*************************************************/
5419
5420/* On entry, ptr is pointing past the bracket character, but on return it
5421points to the closing bracket, or vertical bar, or end of string. The code
5422variable is pointing at the byte into which the BRA operator has been stored.
5423If the ims options are changed at the start (for a (?ims: group) or during any
5424branch, we need to insert an OP_OPT item at the start of every following branch
5425to ensure they get set correctly at run time, and also pass the new options
5426into every subsequent branch compile.
5427
5428This function is used during the pre-compile phase when we are trying to find
5429out the amount of memory needed, as well as during the real compile phase. The
5430value of lengthptr distinguishes the two phases.
5431
5432Arguments:
5433  options        option bits, including any changes for this subpattern
5434  oldims         previous settings of ims option bits
5435  codeptr        -> the address of the current code pointer
5436  ptrptr         -> the address of the current pattern pointer
5437  errorcodeptr   -> pointer to error code variable
5438  lookbehind     TRUE if this is a lookbehind assertion
5439  reset_bracount TRUE to reset the count for each branch
5440  skipbytes      skip this many bytes at start (for brackets and OP_COND)
5441  firstbyteptr   place to put the first required character, or a negative number
5442  reqbyteptr     place to put the last required character, or a negative number
5443  bcptr          pointer to the chain of currently open branches
5444  cd             points to the data block with tables pointers etc.
5445  lengthptr      NULL during the real compile phase
5446                 points to length accumulator during pre-compile phase
5447
5448Returns:         TRUE on success
5449*/
5450
5451static BOOL
5452compile_regex(int options, int oldims, uschar **codeptr, const uschar **ptrptr,
5453  int *errorcodeptr, BOOL lookbehind, BOOL reset_bracount, int skipbytes,
5454  int *firstbyteptr, int *reqbyteptr, branch_chain *bcptr, compile_data *cd,
5455  int *lengthptr)
5456{
5457const uschar *ptr = *ptrptr;
5458uschar *code = *codeptr;
5459uschar *last_branch = code;
5460uschar *start_bracket = code;
5461uschar *reverse_count = NULL;
5462int firstbyte, reqbyte;
5463int branchfirstbyte, branchreqbyte;
5464int length;
5465int orig_bracount;
5466int max_bracount;
5467branch_chain bc;
5468
5469bc.outer = bcptr;
5470bc.current = code;
5471
5472firstbyte = reqbyte = REQ_UNSET;
5473
5474/* Accumulate the length for use in the pre-compile phase. Start with the
5475length of the BRA and KET and any extra bytes that are required at the
5476beginning. We accumulate in a local variable to save frequent testing of
5477lenthptr for NULL. We cannot do this by looking at the value of code at the
5478start and end of each alternative, because compiled items are discarded during
5479the pre-compile phase so that the work space is not exceeded. */
5480
5481length = 2 + 2*LINK_SIZE + skipbytes;
5482
5483/* WARNING: If the above line is changed for any reason, you must also change
5484the code that abstracts option settings at the start of the pattern and makes
5485them global. It tests the value of length for (2 + 2*LINK_SIZE) in the
5486pre-compile phase to find out whether anything has yet been compiled or not. */
5487
5488/* Offset is set zero to mark that this bracket is still open */
5489
5490PUT(code, 1, 0);
5491code += 1 + LINK_SIZE + skipbytes;
5492
5493/* Loop for each alternative branch */
5494
5495orig_bracount = max_bracount = cd->bracount;
5496for (;;)
5497  {
5498  /* For a (?| group, reset the capturing bracket count so that each branch
5499  uses the same numbers. */
5500
5501  if (reset_bracount) cd->bracount = orig_bracount;
5502
5503  /* Handle a change of ims options at the start of the branch */
5504
5505  if ((options & PCRE_IMS) != oldims)
5506    {
5507    *code++ = OP_OPT;
5508    *code++ = options & PCRE_IMS;
5509    length += 2;
5510    }
5511
5512  /* Set up dummy OP_REVERSE if lookbehind assertion */
5513
5514  if (lookbehind)
5515    {
5516    *code++ = OP_REVERSE;
5517    reverse_count = code;
5518    PUTINC(code, 0, 0);
5519    length += 1 + LINK_SIZE;
5520    }
5521
5522  /* Now compile the branch; in the pre-compile phase its length gets added
5523  into the length. */
5524
5525  if (!compile_branch(&options, &code, &ptr, errorcodeptr, &branchfirstbyte,
5526        &branchreqbyte, &bc, cd, (lengthptr == NULL)? NULL : &length))
5527    {
5528    *ptrptr = ptr;
5529    return FALSE;
5530    }
5531
5532  /* Keep the highest bracket count in case (?| was used and some branch
5533  has fewer than the rest. */
5534
5535  if (cd->bracount > max_bracount) max_bracount = cd->bracount;
5536
5537  /* In the real compile phase, there is some post-processing to be done. */
5538
5539  if (lengthptr == NULL)
5540    {
5541    /* If this is the first branch, the firstbyte and reqbyte values for the
5542    branch become the values for the regex. */
5543
5544    if (*last_branch != OP_ALT)
5545      {
5546      firstbyte = branchfirstbyte;
5547      reqbyte = branchreqbyte;
5548      }
5549
5550    /* If this is not the first branch, the first char and reqbyte have to
5551    match the values from all the previous branches, except that if the
5552    previous value for reqbyte didn't have REQ_VARY set, it can still match,
5553    and we set REQ_VARY for the regex. */
5554
5555    else
5556      {
5557      /* If we previously had a firstbyte, but it doesn't match the new branch,
5558      we have to abandon the firstbyte for the regex, but if there was
5559      previously no reqbyte, it takes on the value of the old firstbyte. */
5560
5561      if (firstbyte >= 0 && firstbyte != branchfirstbyte)
5562        {
5563        if (reqbyte < 0) reqbyte = firstbyte;
5564        firstbyte = REQ_NONE;
5565        }
5566
5567      /* If we (now or from before) have no firstbyte, a firstbyte from the
5568      branch becomes a reqbyte if there isn't a branch reqbyte. */
5569
5570      if (firstbyte < 0 && branchfirstbyte >= 0 && branchreqbyte < 0)
5571          branchreqbyte = branchfirstbyte;
5572
5573      /* Now ensure that the reqbytes match */
5574
5575      if ((reqbyte & ~REQ_VARY) != (branchreqbyte & ~REQ_VARY))
5576        reqbyte = REQ_NONE;
5577      else reqbyte |= branchreqbyte;   /* To "or" REQ_VARY */
5578      }
5579
5580    /* If lookbehind, check that this branch matches a fixed-length string, and
5581    put the length into the OP_REVERSE item. Temporarily mark the end of the
5582    branch with OP_END. */
5583
5584    if (lookbehind)
5585      {
5586      int fixed_length;
5587      *code = OP_END;
5588      fixed_length = find_fixedlength(last_branch, options);
5589      DPRINTF(("fixed length = %d\n", fixed_length));
5590      if (fixed_length < 0)
5591        {
5592        *errorcodeptr = (fixed_length == -2)? ERR36 : ERR25;
5593        *ptrptr = ptr;
5594        return FALSE;
5595        }
5596      PUT(reverse_count, 0, fixed_length);
5597      }
5598    }
5599
5600  /* Reached end of expression, either ')' or end of pattern. In the real
5601  compile phase, go back through the alternative branches and reverse the chain
5602  of offsets, with the field in the BRA item now becoming an offset to the
5603  first alternative. If there are no alternatives, it points to the end of the
5604  group. The length in the terminating ket is always the length of the whole
5605  bracketed item. If any of the ims options were changed inside the group,
5606  compile a resetting op-code following, except at the very end of the pattern.
5607  Return leaving the pointer at the terminating char. */
5608
5609  if (*ptr != '|')
5610    {
5611    if (lengthptr == NULL)
5612      {
5613      int branch_length = code - last_branch;
5614      do
5615        {
5616        int prev_length = GET(last_branch, 1);
5617        PUT(last_branch, 1, branch_length);
5618        branch_length = prev_length;
5619        last_branch -= branch_length;
5620        }
5621      while (branch_length > 0);
5622      }
5623
5624    /* Fill in the ket */
5625
5626    *code = OP_KET;
5627    PUT(code, 1, code - start_bracket);
5628    code += 1 + LINK_SIZE;
5629
5630    /* Resetting option if needed */
5631
5632    if ((options & PCRE_IMS) != oldims && *ptr == ')')
5633      {
5634      *code++ = OP_OPT;
5635      *code++ = oldims;
5636      length += 2;
5637      }
5638
5639    /* Retain the highest bracket number, in case resetting was used. */
5640
5641    cd->bracount = max_bracount;
5642
5643    /* Set values to pass back */
5644
5645    *codeptr = code;
5646    *ptrptr = ptr;
5647    *firstbyteptr = firstbyte;
5648    *reqbyteptr = reqbyte;
5649    if (lengthptr != NULL)
5650      {
5651      if (OFLOW_MAX - *lengthptr < length)
5652        {
5653        *errorcodeptr = ERR20;
5654        return FALSE;
5655        }
5656      *lengthptr += length;
5657      }
5658    return TRUE;
5659    }
5660
5661  /* Another branch follows. In the pre-compile phase, we can move the code
5662  pointer back to where it was for the start of the first branch. (That is,
5663  pretend that each branch is the only one.)
5664
5665  In the real compile phase, insert an ALT node. Its length field points back
5666  to the previous branch while the bracket remains open. At the end the chain
5667  is reversed. It's done like this so that the start of the bracket has a
5668  zero offset until it is closed, making it possible to detect recursion. */
5669
5670  if (lengthptr != NULL)
5671    {
5672    code = *codeptr + 1 + LINK_SIZE + skipbytes;
5673    length += 1 + LINK_SIZE;
5674    }
5675  else
5676    {
5677    *code = OP_ALT;
5678    PUT(code, 1, code - last_branch);
5679    bc.current = last_branch = code;
5680    code += 1 + LINK_SIZE;
5681    }
5682
5683  ptr++;
5684  }
5685/* Control never reaches here */
5686}
5687
5688
5689
5690
5691/*************************************************
5692*          Check for anchored expression         *
5693*************************************************/
5694
5695/* Try to find out if this is an anchored regular expression. Consider each
5696alternative branch. If they all start with OP_SOD or OP_CIRC, or with a bracket
5697all of whose alternatives start with OP_SOD or OP_CIRC (recurse ad lib), then
5698it's anchored. However, if this is a multiline pattern, then only OP_SOD
5699counts, since OP_CIRC can match in the middle.
5700
5701We can also consider a regex to be anchored if OP_SOM starts all its branches.
5702This is the code for \G, which means "match at start of match position, taking
5703into account the match offset".
5704
5705A branch is also implicitly anchored if it starts with .* and DOTALL is set,
5706because that will try the rest of the pattern at all possible matching points,
5707so there is no point trying again.... er ....
5708
5709.... except when the .* appears inside capturing parentheses, and there is a
5710subsequent back reference to those parentheses. We haven't enough information
5711to catch that case precisely.
5712
5713At first, the best we could do was to detect when .* was in capturing brackets
5714and the highest back reference was greater than or equal to that level.
5715However, by keeping a bitmap of the first 31 back references, we can catch some
5716of the more common cases more precisely.
5717
5718Arguments:
5719  code           points to start of expression (the bracket)
5720  options        points to the options setting
5721  bracket_map    a bitmap of which brackets we are inside while testing; this
5722                  handles up to substring 31; after that we just have to take
5723                  the less precise approach
5724  backref_map    the back reference bitmap
5725
5726Returns:     TRUE or FALSE
5727*/
5728
5729static BOOL
5730is_anchored(register const uschar *code, int *options, unsigned int bracket_map,
5731  unsigned int backref_map)
5732{
5733do {
5734   const uschar *scode = first_significant_code(code + _pcre_OP_lengths[*code],
5735     options, PCRE_MULTILINE, FALSE);
5736   register int op = *scode;
5737
5738   /* Non-capturing brackets */
5739
5740   if (op == OP_BRA)
5741     {
5742     if (!is_anchored(scode, options, bracket_map, backref_map)) return FALSE;
5743     }
5744
5745   /* Capturing brackets */
5746
5747   else if (op == OP_CBRA)
5748     {
5749     int n = GET2(scode, 1+LINK_SIZE);
5750     int new_map = bracket_map | ((n < 32)? (1 << n) : 1);
5751     if (!is_anchored(scode, options, new_map, backref_map)) return FALSE;
5752     }
5753
5754   /* Other brackets */
5755
5756   else if (op == OP_ASSERT || op == OP_ONCE || op == OP_COND)
5757     {
5758     if (!is_anchored(scode, options, bracket_map, backref_map)) return FALSE;
5759     }
5760
5761   /* .* is not anchored unless DOTALL is set (which generates OP_ALLANY) and
5762   it isn't in brackets that are or may be referenced. */
5763
5764   else if ((op == OP_TYPESTAR || op == OP_TYPEMINSTAR ||
5765             op == OP_TYPEPOSSTAR))
5766     {
5767     if (scode[1] != OP_ALLANY || (bracket_map & backref_map) != 0)
5768       return FALSE;
5769     }
5770
5771   /* Check for explicit anchoring */
5772
5773   else if (op != OP_SOD && op != OP_SOM &&
5774           ((*options & PCRE_MULTILINE) != 0 || op != OP_CIRC))
5775     return FALSE;
5776   code += GET(code, 1);
5777   }
5778while (*code == OP_ALT);   /* Loop for each alternative */
5779return TRUE;
5780}
5781
5782
5783
5784/*************************************************
5785*         Check for starting with ^ or .*        *
5786*************************************************/
5787
5788/* This is called to find out if every branch starts with ^ or .* so that
5789"first char" processing can be done to speed things up in multiline
5790matching and for non-DOTALL patterns that start with .* (which must start at
5791the beginning or after \n). As in the case of is_anchored() (see above), we
5792have to take account of back references to capturing brackets that contain .*
5793because in that case we can't make the assumption.
5794
5795Arguments:
5796  code           points to start of expression (the bracket)
5797  bracket_map    a bitmap of which brackets we are inside while testing; this
5798                  handles up to substring 31; after that we just have to take
5799                  the less precise approach
5800  backref_map    the back reference bitmap
5801
5802Returns:         TRUE or FALSE
5803*/
5804
5805static BOOL
5806is_startline(const uschar *code, unsigned int bracket_map,
5807  unsigned int backref_map)
5808{
5809do {
5810   const uschar *scode = first_significant_code(code + _pcre_OP_lengths[*code],
5811     NULL, 0, FALSE);
5812   register int op = *scode;
5813
5814   /* Non-capturing brackets */
5815
5816   if (op == OP_BRA)
5817     {
5818     if (!is_startline(scode, bracket_map, backref_map)) return FALSE;
5819     }
5820
5821   /* Capturing brackets */
5822
5823   else if (op == OP_CBRA)
5824     {
5825     int n = GET2(scode, 1+LINK_SIZE);
5826     int new_map = bracket_map | ((n < 32)? (1 << n) : 1);
5827     if (!is_startline(scode, new_map, backref_map)) return FALSE;
5828     }
5829
5830   /* Other brackets */
5831
5832   else if (op == OP_ASSERT || op == OP_ONCE || op == OP_COND)
5833     { if (!is_startline(scode, bracket_map, backref_map)) return FALSE; }
5834
5835   /* .* means "start at start or after \n" if it isn't in brackets that
5836   may be referenced. */
5837
5838   else if (op == OP_TYPESTAR || op == OP_TYPEMINSTAR || op == OP_TYPEPOSSTAR)
5839     {
5840     if (scode[1] != OP_ANY || (bracket_map & backref_map) != 0) return FALSE;
5841     }
5842
5843   /* Check for explicit circumflex */
5844
5845   else if (op != OP_CIRC) return FALSE;
5846
5847   /* Move on to the next alternative */
5848
5849   code += GET(code, 1);
5850   }
5851while (*code == OP_ALT);  /* Loop for each alternative */
5852return TRUE;
5853}
5854
5855
5856
5857/*************************************************
5858*       Check for asserted fixed first char      *
5859*************************************************/
5860
5861/* During compilation, the "first char" settings from forward assertions are
5862discarded, because they can cause conflicts with actual literals that follow.
5863However, if we end up without a first char setting for an unanchored pattern,
5864it is worth scanning the regex to see if there is an initial asserted first
5865char. If all branches start with the same asserted char, or with a bracket all
5866of whose alternatives start with the same asserted char (recurse ad lib), then
5867we return that char, otherwise -1.
5868
5869Arguments:
5870  code       points to start of expression (the bracket)
5871  options    pointer to the options (used to check casing changes)
5872  inassert   TRUE if in an assertion
5873
5874Returns:     -1 or the fixed first char
5875*/
5876
5877static int
5878find_firstassertedchar(const uschar *code, int *options, BOOL inassert)
5879{
5880register int c = -1;
5881do {
5882   int d;
5883   const uschar *scode =
5884     first_significant_code(code + 1+LINK_SIZE, options, PCRE_CASELESS, TRUE);
5885   register int op = *scode;
5886
5887   switch(op)
5888     {
5889     default:
5890     return -1;
5891
5892     case OP_BRA:
5893     case OP_CBRA:
5894     case OP_ASSERT:
5895     case OP_ONCE:
5896     case OP_COND:
5897     if ((d = find_firstassertedchar(scode, options, op == OP_ASSERT)) < 0)
5898       return -1;
5899     if (c < 0) c = d; else if (c != d) return -1;
5900     break;
5901
5902     case OP_EXACT:       /* Fall through */
5903     scode += 2;
5904
5905     case OP_CHAR:
5906     case OP_CHARNC:
5907     case OP_PLUS:
5908     case OP_MINPLUS:
5909     case OP_POSPLUS:
5910     if (!inassert) return -1;
5911     if (c < 0)
5912       {
5913       c = scode[1];
5914       if ((*options & PCRE_CASELESS) != 0) c |= REQ_CASELESS;
5915       }
5916     else if (c != scode[1]) return -1;
5917     break;
5918     }
5919
5920   code += GET(code, 1);
5921   }
5922while (*code == OP_ALT);
5923return c;
5924}
5925
5926
5927
5928/*************************************************
5929*        Compile a Regular Expression            *
5930*************************************************/
5931
5932/* This function takes a string and returns a pointer to a block of store
5933holding a compiled version of the expression. The original API for this
5934function had no error code return variable; it is retained for backwards
5935compatibility. The new function is given a new name.
5936
5937Arguments:
5938  pattern       the regular expression
5939  options       various option bits
5940  errorcodeptr  pointer to error code variable (pcre_compile2() only)
5941                  can be NULL if you don't want a code value
5942  errorptr      pointer to pointer to error text
5943  erroroffset   ptr offset in pattern where error was detected
5944  tables        pointer to character tables or NULL
5945
5946Returns:        pointer to compiled data block, or NULL on error,
5947                with errorptr and erroroffset set
5948*/
5949
5950PCRE_EXP_DEFN pcre * PCRE_CALL_CONVENTION
5951pcre_compile(const char *pattern, int options, const char **errorptr,
5952  int *erroroffset, const unsigned char *tables)
5953{
5954return pcre_compile2(pattern, options, NULL, errorptr, erroroffset, tables);
5955}
5956
5957
5958PCRE_EXP_DEFN pcre * PCRE_CALL_CONVENTION
5959pcre_compile2(const char *pattern, int options, int *errorcodeptr,
5960  const char **errorptr, int *erroroffset, const unsigned char *tables)
5961{
5962real_pcre *re;
5963int length = 1;  /* For final END opcode */
5964int firstbyte, reqbyte, newline;
5965int errorcode = 0;
5966int skipatstart = 0;
5967#ifdef SUPPORT_UTF8
5968BOOL utf8;
5969#endif
5970size_t size;
5971uschar *code;
5972const uschar *codestart;
5973const uschar *ptr;
5974compile_data compile_block;
5975compile_data *cd = &compile_block;
5976
5977/* This space is used for "compiling" into during the first phase, when we are
5978computing the amount of memory that is needed. Compiled items are thrown away
5979as soon as possible, so that a fairly large buffer should be sufficient for
5980this purpose. The same space is used in the second phase for remembering where
5981to fill in forward references to subpatterns. */
5982
5983uschar cworkspace[COMPILE_WORK_SIZE];
5984
5985/* Set this early so that early errors get offset 0. */
5986
5987ptr = (const uschar *)pattern;
5988
5989/* We can't pass back an error message if errorptr is NULL; I guess the best we
5990can do is just return NULL, but we can set a code value if there is a code
5991pointer. */
5992
5993if (errorptr == NULL)
5994  {
5995  if (errorcodeptr != NULL) *errorcodeptr = 99;
5996  return NULL;
5997  }
5998
5999*errorptr = NULL;
6000if (errorcodeptr != NULL) *errorcodeptr = ERR0;
6001
6002/* However, we can give a message for this error */
6003
6004if (erroroffset == NULL)
6005  {
6006  errorcode = ERR16;
6007  goto PCRE_EARLY_ERROR_RETURN2;
6008  }
6009
6010*erroroffset = 0;
6011
6012/* Can't support UTF8 unless PCRE has been compiled to include the code. */
6013
6014#ifdef SUPPORT_UTF8
6015utf8 = (options & PCRE_UTF8) != 0;
6016if (utf8 && (options & PCRE_NO_UTF8_CHECK) == 0 &&
6017     (*erroroffset = _pcre_valid_utf8((uschar *)pattern, -1)) >= 0)
6018  {
6019  errorcode = ERR44;
6020  goto PCRE_EARLY_ERROR_RETURN2;
6021  }
6022#else
6023if ((options & PCRE_UTF8) != 0)
6024  {
6025  errorcode = ERR32;
6026  goto PCRE_EARLY_ERROR_RETURN;
6027  }
6028#endif
6029
6030if ((options & ~PUBLIC_OPTIONS) != 0)
6031  {
6032  errorcode = ERR17;
6033  goto PCRE_EARLY_ERROR_RETURN;
6034  }
6035
6036/* Set up pointers to the individual character tables */
6037
6038if (tables == NULL) tables = _pcre_default_tables;
6039cd->lcc = tables + lcc_offset;
6040cd->fcc = tables + fcc_offset;
6041cd->cbits = tables + cbits_offset;
6042cd->ctypes = tables + ctypes_offset;
6043
6044/* Check for global one-time settings at the start of the pattern, and remember
6045the offset for later. */
6046
6047while (ptr[skipatstart] == '(' && ptr[skipatstart+1] == '*')
6048  {
6049  int newnl = 0;
6050  int newbsr = 0;
6051
6052  if (strncmp((char *)(ptr+skipatstart+2), "CR)", 3) == 0)
6053    { skipatstart += 5; newnl = PCRE_NEWLINE_CR; }
6054  else if (strncmp((char *)(ptr+skipatstart+2), "LF)", 3)  == 0)
6055    { skipatstart += 5; newnl = PCRE_NEWLINE_LF; }
6056  else if (strncmp((char *)(ptr+skipatstart+2), "CRLF)", 5)  == 0)
6057    { skipatstart += 7; newnl = PCRE_NEWLINE_CR + PCRE_NEWLINE_LF; }
6058  else if (strncmp((char *)(ptr+skipatstart+2), "ANY)", 4) == 0)
6059    { skipatstart += 6; newnl = PCRE_NEWLINE_ANY; }
6060  else if (strncmp((char *)(ptr+skipatstart+2), "ANYCRLF)", 8)  == 0)
6061    { skipatstart += 10; newnl = PCRE_NEWLINE_ANYCRLF; }
6062
6063  else if (strncmp((char *)(ptr+skipatstart+2), "BSR_ANYCRLF)", 12) == 0)
6064    { skipatstart += 14; newbsr = PCRE_BSR_ANYCRLF; }
6065  else if (strncmp((char *)(ptr+skipatstart+2), "BSR_UNICODE)", 12) == 0)
6066    { skipatstart += 14; newbsr = PCRE_BSR_UNICODE; }
6067
6068  if (newnl != 0)
6069    options = (options & ~PCRE_NEWLINE_BITS) | newnl;
6070  else if (newbsr != 0)
6071    options = (options & ~(PCRE_BSR_ANYCRLF|PCRE_BSR_UNICODE)) | newbsr;
6072  else break;
6073  }
6074
6075/* Check validity of \R options. */
6076
6077switch (options & (PCRE_BSR_ANYCRLF|PCRE_BSR_UNICODE))
6078  {
6079  case 0:
6080  case PCRE_BSR_ANYCRLF:
6081  case PCRE_BSR_UNICODE:
6082  break;
6083  default: errorcode = ERR56; goto PCRE_EARLY_ERROR_RETURN;
6084  }
6085
6086/* Handle different types of newline. The three bits give seven cases. The
6087current code allows for fixed one- or two-byte sequences, plus "any" and
6088"anycrlf". */
6089
6090switch (options & PCRE_NEWLINE_BITS)
6091  {
6092  case 0: newline = NEWLINE; break;   /* Build-time default */
6093  case PCRE_NEWLINE_CR: newline = '\r'; break;
6094  case PCRE_NEWLINE_LF: newline = '\n'; break;
6095  case PCRE_NEWLINE_CR+
6096       PCRE_NEWLINE_LF: newline = ('\r' << 8) | '\n'; break;
6097  case PCRE_NEWLINE_ANY: newline = -1; break;
6098  case PCRE_NEWLINE_ANYCRLF: newline = -2; break;
6099  default: errorcode = ERR56; goto PCRE_EARLY_ERROR_RETURN;
6100  }
6101
6102if (newline == -2)
6103  {
6104  cd->nltype = NLTYPE_ANYCRLF;
6105  }
6106else if (newline < 0)
6107  {
6108  cd->nltype = NLTYPE_ANY;
6109  }
6110else
6111  {
6112  cd->nltype = NLTYPE_FIXED;
6113  if (newline > 255)
6114    {
6115    cd->nllen = 2;
6116    cd->nl[0] = (newline >> 8) & 255;
6117    cd->nl[1] = newline & 255;
6118    }
6119  else
6120    {
6121    cd->nllen = 1;
6122    cd->nl[0] = newline;
6123    }
6124  }
6125
6126/* Maximum back reference and backref bitmap. The bitmap records up to 31 back
6127references to help in deciding whether (.*) can be treated as anchored or not.
6128*/
6129
6130cd->top_backref = 0;
6131cd->backref_map = 0;
6132
6133/* Reflect pattern for debugging output */
6134
6135DPRINTF(("------------------------------------------------------------------\n"));
6136DPRINTF(("%s\n", pattern));
6137
6138/* Pretend to compile the pattern while actually just accumulating the length
6139of memory required. This behaviour is triggered by passing a non-NULL final
6140argument to compile_regex(). We pass a block of workspace (cworkspace) for it
6141to compile parts of the pattern into; the compiled code is discarded when it is
6142no longer needed, so hopefully this workspace will never overflow, though there
6143is a test for its doing so. */
6144
6145cd->bracount = cd->final_bracount = 0;
6146cd->names_found = 0;
6147cd->name_entry_size = 0;
6148cd->name_table = NULL;
6149cd->start_workspace = cworkspace;
6150cd->start_code = cworkspace;
6151cd->hwm = cworkspace;
6152cd->start_pattern = (const uschar *)pattern;
6153cd->end_pattern = (const uschar *)(pattern + strlen(pattern));
6154cd->req_varyopt = 0;
6155cd->external_options = options;
6156cd->external_flags = 0;
6157
6158/* Now do the pre-compile. On error, errorcode will be set non-zero, so we
6159don't need to look at the result of the function here. The initial options have
6160been put into the cd block so that they can be changed if an option setting is
6161found within the regex right at the beginning. Bringing initial option settings
6162outside can help speed up starting point checks. */
6163
6164ptr += skipatstart;
6165code = cworkspace;
6166*code = OP_BRA;
6167(void)compile_regex(cd->external_options, cd->external_options & PCRE_IMS,
6168  &code, &ptr, &errorcode, FALSE, FALSE, 0, &firstbyte, &reqbyte, NULL, cd,
6169  &length);
6170if (errorcode != 0) goto PCRE_EARLY_ERROR_RETURN;
6171
6172DPRINTF(("end pre-compile: length=%d workspace=%d\n", length,
6173  cd->hwm - cworkspace));
6174
6175if (length > MAX_PATTERN_SIZE)
6176  {
6177  errorcode = ERR20;
6178  goto PCRE_EARLY_ERROR_RETURN;
6179  }
6180
6181/* Compute the size of data block needed and get it, either from malloc or
6182externally provided function. Integer overflow should no longer be possible
6183because nowadays we limit the maximum value of cd->names_found and
6184cd->name_entry_size. */
6185
6186size = length + sizeof(real_pcre) + cd->names_found * (cd->name_entry_size + 3);
6187re = (real_pcre *)(pcre_malloc)(size);
6188
6189if (re == NULL)
6190  {
6191  errorcode = ERR21;
6192  goto PCRE_EARLY_ERROR_RETURN;
6193  }
6194
6195/* Put in the magic number, and save the sizes, initial options, internal
6196flags, and character table pointer. NULL is used for the default character
6197tables. The nullpad field is at the end; it's there to help in the case when a
6198regex compiled on a system with 4-byte pointers is run on another with 8-byte
6199pointers. */
6200
6201re->magic_number = MAGIC_NUMBER;
6202re->size = size;
6203re->options = cd->external_options;
6204re->flags = cd->external_flags;
6205re->dummy1 = 0;
6206re->first_byte = 0;
6207re->req_byte = 0;
6208re->name_table_offset = sizeof(real_pcre);
6209re->name_entry_size = cd->name_entry_size;
6210re->name_count = cd->names_found;
6211re->ref_count = 0;
6212re->tables = (tables == _pcre_default_tables)? NULL : tables;
6213re->nullpad = NULL;
6214
6215/* The starting points of the name/number translation table and of the code are
6216passed around in the compile data block. The start/end pattern and initial
6217options are already set from the pre-compile phase, as is the name_entry_size
6218field. Reset the bracket count and the names_found field. Also reset the hwm
6219field; this time it's used for remembering forward references to subpatterns.
6220*/
6221
6222cd->final_bracount = cd->bracount;  /* Save for checking forward references */
6223cd->bracount = 0;
6224cd->names_found = 0;
6225cd->name_table = (uschar *)re + re->name_table_offset;
6226codestart = cd->name_table + re->name_entry_size * re->name_count;
6227cd->start_code = codestart;
6228cd->hwm = cworkspace;
6229cd->req_varyopt = 0;
6230cd->had_accept = FALSE;
6231
6232/* Set up a starting, non-extracting bracket, then compile the expression. On
6233error, errorcode will be set non-zero, so we don't need to look at the result
6234of the function here. */
6235
6236ptr = (const uschar *)pattern + skipatstart;
6237code = (uschar *)codestart;
6238*code = OP_BRA;
6239(void)compile_regex(re->options, re->options & PCRE_IMS, &code, &ptr,
6240  &errorcode, FALSE, FALSE, 0, &firstbyte, &reqbyte, NULL, cd, NULL);
6241re->top_bracket = cd->bracount;
6242re->top_backref = cd->top_backref;
6243re->flags = cd->external_flags;
6244
6245if (cd->had_accept) reqbyte = -1;   /* Must disable after (*ACCEPT) */
6246
6247/* If not reached end of pattern on success, there's an excess bracket. */
6248
6249if (errorcode == 0 && *ptr != 0) errorcode = ERR22;
6250
6251/* Fill in the terminating state and check for disastrous overflow, but
6252if debugging, leave the test till after things are printed out. */
6253
6254*code++ = OP_END;
6255
6256#ifndef DEBUG
6257if (code - codestart > length) errorcode = ERR23;
6258#endif
6259
6260/* Fill in any forward references that are required. */
6261
6262while (errorcode == 0 && cd->hwm > cworkspace)
6263  {
6264  int offset, recno;
6265  const uschar *groupptr;
6266  cd->hwm -= LINK_SIZE;
6267  offset = GET(cd->hwm, 0);
6268  recno = GET(codestart, offset);
6269  groupptr = find_bracket(codestart, (re->options & PCRE_UTF8) != 0, recno);
6270  if (groupptr == NULL) errorcode = ERR53;
6271    else PUT(((uschar *)codestart), offset, groupptr - codestart);
6272  }
6273
6274/* Give an error if there's back reference to a non-existent capturing
6275subpattern. */
6276
6277if