+++ /dev/null
-Puff -- A Simple Inflate
-3 Mar 2003
-Mark Adler
-madler@alumni.caltech.edu
-
-What this is --
-
-puff.c provides the routine puff() to decompress the deflate data format. It
-does so more slowly than zlib, but the code is about one-fifth the size of the
-inflate code in zlib, and written to be very easy to read.
-
-Why I wrote this --
-
-puff.c was written to document the deflate format unambiguously, by virtue of
-being working C code. It is meant to supplement RFC 1951, which formally
-describes the deflate format. I have received many questions on details of the
-deflate format, and I hope that reading this code will answer those questions.
-puff.c is heavily commented with details of the deflate format, especially
-those little nooks and cranies of the format that might not be obvious from a
-specification.
-
-puff.c may also be useful in applications where code size or memory usage is a
-very limited resource, and speed is not as important.
-
-How to use it --
-
-Well, most likely you should just be reading puff.c and using zlib for actual
-applications, but if you must ...
-
-Include puff.h in your code, which provides this prototype:
-
-int puff(unsigned char *dest, /* pointer to destination pointer */
- unsigned long *destlen, /* amount of output space */
- unsigned char *source, /* pointer to source data pointer */
- unsigned long *sourcelen); /* amount of input available */
-
-Then you can call puff() to decompress a deflate stream that is in memory in
-its entirety at source, to a sufficiently sized block of memory for the
-decompressed data at dest. puff() is the only external symbol in puff.c The
-only C library functions that puff.c needs are setjmp() and longjmp(), which
-are used to simplify error checking in the code to improve readabilty. puff.c
-does no memory allocation, and uses less than 2K bytes off of the stack.
-
-If destlen is not enough space for the uncompressed data, then inflate will
-return an error without writing more than destlen bytes. Note that this means
-that in order to decompress the deflate data successfully, you need to know
-the size of the uncompressed data ahead of time.
-
-If needed, puff() can determine the size of the uncompressed data with no
-output space. This is done by passing dest equal to (unsigned char *)0. Then
-the initial value of *destlen is ignored and *destlen is set to the length of
-the uncompressed data. So if the size of the uncompressed data is not known,
-then two passes of puff() can be used--first to determine the size, and second
-to do the actual inflation after allocating the appropriate memory. Not
-pretty, but it works. (This is one of the reasons you should be using zlib.)
-
-The deflate format is self-terminating. If the deflate stream does not end
-in *sourcelen bytes, puff() will return an error without reading at or past
-endsource.
-
-On return, *sourcelen is updated to the amount of input data consumed, and
-*destlen is updated to the size of the uncompressed data. See the comments
-in puff.c for the possible return codes for puff().
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