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diff --git a/zlib/contrib/puff/README b/zlib/contrib/puff/README deleted file mode 100644 index bbc4cb5..0000000 --- a/zlib/contrib/puff/README +++ /dev/null @@ -1,63 +0,0 @@ -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(). |