Custom Query (1630 matches)

The alist-ref call in the definition of z3:error in the source file z3.scm has a missing argument.

The code currently says:

(alist-ref code errors "unknown")

If the optional DEFAULT argument is given, the optional TEST argument which precedes it must also be specified in the call. The correct value here is eqv?

So it should read:

(alist-ref code errors eqv? "unknown")

The effect of the bug is that error messages are not displayed and the program confuses the end user by complaining that "unknown" isn't a function.

RFC1951 is the DEFLATE format. RFC1952 is the gzip file format. A gzip file is a data stream encoded using the DEFLATE format, in a file wrapper specified by RFC1952.

Although it is presented as a gzip egg that "Provides functions to read and write compressed data using the gzip algorithm", some of the calls actually use the raw DEFLATE format without being clear about it, resulting in unexpected errors.

Four interfaces are specified by this egg: the raw data interface, the buffer interface, the file system interface and the port interface.

The first two only read and write DEFLATE (RFC1951) format, while the second two read and write gzip (RFC1952) format.

The upshot is that if one reads a gzip file into a buffer and then attempts to use the z3 raw data or buffer interface functions to decode it, an error will result because they do not understand gzip file format.

In the interim, the egg documentation should specify the data formats being handled by each set of functions.

In the long run a buffer interface that handles RFC1952 format in memory would be useful because this format is commonly used, for instance, for data transmission from web servers to clients. At present if a RFC1952 stream is captured in a memory buffer the only way z3 can decode it is by writing to a temporary file and then using the file system or port interface to decode the file contents.

See attached patch. This also makes the abort optional.