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author | Mark Adler <madler@alumni.caltech.edu> | 2016-11-15 20:45:01 -0700 |
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committer | Mark Adler <madler@alumni.caltech.edu> | 2016-12-04 07:48:47 -0800 |
commit | 37281ac222ee7ceb8cc3253f13c8fa26a88dd566 (patch) | |
tree | 0ac0add0b56a769f7714e3a2af5a8b0210803f75 /uncompr.c | |
parent | 001300d0d91f75f03eed5ec97eca160452f62d61 (diff) | |
download | zlib-37281ac222ee7ceb8cc3253f13c8fa26a88dd566.tar.gz |
Add uncompress2() function, which returns the input size used.
Diffstat (limited to 'uncompr.c')
-rw-r--r-- | uncompr.c | 47 |
1 files changed, 30 insertions, 17 deletions
@@ -1,5 +1,5 @@ /* uncompr.c -- decompress a memory buffer - * Copyright (C) 1995-2003, 2010, 2014 Jean-loup Gailly, Mark Adler + * Copyright (C) 1995-2003, 2010, 2014, 2016 Jean-loup Gailly, Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h */ @@ -9,31 +9,34 @@ #include "zlib.h" /* =========================================================================== - Decompresses the source buffer into the destination buffer. sourceLen is - the byte length of the source buffer. Upon entry, destLen is the total - size of the destination buffer, which must be large enough to hold the - entire uncompressed data. (The size of the uncompressed data must have - been saved previously by the compressor and transmitted to the decompressor - by some mechanism outside the scope of this compression library.) - Upon exit, destLen is the actual size of the compressed buffer. + Decompresses the source buffer into the destination buffer. *sourceLen is + the byte length of the source buffer. Upon entry, *destLen is the total size + of the destination buffer, which must be large enough to hold the entire + uncompressed data. (The size of the uncompressed data must have been saved + previously by the compressor and transmitted to the decompressor by some + mechanism outside the scope of this compression library.) Upon exit, + *destLen is the size of the decompressed data and *sourceLen is the number + of source bytes consumed. Upon return, source + *sourceLen points to the + first unused input byte. - uncompress returns Z_OK if success, Z_MEM_ERROR if there was not - enough memory, Z_BUF_ERROR if there was not enough room in the output - buffer, or Z_DATA_ERROR if the input data was corrupted, including if the - input data is an incomplete zlib stream. + uncompress returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_BUF_ERROR if there was not enough room in the output buffer, or + Z_DATA_ERROR if the input data was corrupted, including if the input data is + an incomplete zlib stream. */ -int ZEXPORT uncompress (dest, destLen, source, sourceLen) +int ZEXPORT uncompress2 (dest, destLen, source, sourceLen) Bytef *dest; uLongf *destLen; const Bytef *source; - uLong sourceLen; + uLong *sourceLen; { z_stream stream; int err; const uInt max = (uInt)0 - 1; - uLong left; + uLong len, left; Byte buf[1]; /* for detection of incomplete stream when *destLen == 0 */ + len = *sourceLen; if (*destLen) { left = *destLen; *destLen = 0; @@ -61,12 +64,13 @@ int ZEXPORT uncompress (dest, destLen, source, sourceLen) left -= stream.avail_out; } if (stream.avail_in == 0) { - stream.avail_in = sourceLen > (uLong)max ? max : (uInt)sourceLen; - sourceLen -= stream.avail_in; + stream.avail_in = len > (uLong)max ? max : (uInt)len; + len -= stream.avail_in; } err = inflate(&stream, Z_NO_FLUSH); } while (err == Z_OK); + *sourceLen -= len + stream.avail_in; if (dest != buf) *destLen = stream.total_out; else if (stream.total_out && err == Z_BUF_ERROR) @@ -78,3 +82,12 @@ int ZEXPORT uncompress (dest, destLen, source, sourceLen) err == Z_BUF_ERROR && left + stream.avail_out ? Z_DATA_ERROR : err; } + +int ZEXPORT uncompress (dest, destLen, source, sourceLen) + Bytef *dest; + uLongf *destLen; + const Bytef *source; + uLong sourceLen; +{ + return uncompress2(dest, destLen, source, &sourceLen); +} |