| /* uncompr.c -- decompress a memory buffer |
| * Copyright (C) 1995-2003, 2010, 2014 Jean-loup Gailly, Mark Adler |
| * For conditions of distribution and use, see copyright notice in zlib.h |
| */ |
| |
| /* @(#) $Id$ */ |
| |
| #define ZLIB_INTERNAL |
| #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. |
| |
| 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) |
| Bytef *dest; |
| uLongf *destLen; |
| const Bytef *source; |
| uLong sourceLen; |
| { |
| z_stream stream; |
| int err; |
| const uInt max = -1; |
| uLong left; |
| Byte buf[1]; /* for detection of incomplete stream when *destLen == 0 */ |
| |
| if (*destLen) { |
| left = *destLen; |
| *destLen = 0; |
| } |
| else { |
| left = 1; |
| dest = buf; |
| } |
| |
| stream.next_in = (z_const Bytef *)source; |
| stream.avail_in = 0; |
| stream.zalloc = (alloc_func)0; |
| stream.zfree = (free_func)0; |
| stream.opaque = (voidpf)0; |
| |
| err = inflateInit(&stream); |
| if (err != Z_OK) return err; |
| |
| stream.next_out = dest; |
| stream.avail_out = 0; |
| |
| do { |
| if (stream.avail_out == 0) { |
| stream.avail_out = left > (uLong)max ? max : (uInt)left; |
| left -= stream.avail_out; |
| } |
| if (stream.avail_in == 0) { |
| stream.avail_in = sourceLen > (uLong)max ? max : (uInt)sourceLen; |
| sourceLen -= stream.avail_in; |
| } |
| err = inflate(&stream, Z_NO_FLUSH); |
| } while (err == Z_OK); |
| |
| if (dest != buf) |
| *destLen = stream.total_out; |
| else if (stream.total_out && err == Z_BUF_ERROR) |
| left = 1; |
| |
| inflateEnd(&stream); |
| return err == Z_STREAM_END ? Z_OK : |
| err == Z_NEED_DICT ? Z_DATA_ERROR : |
| err == Z_BUF_ERROR && left + stream.avail_out ? Z_DATA_ERROR : |
| err; |
| } |