62 lines
2 KiB
C
62 lines
2 KiB
C
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/* uncompr.c -- decompress a memory buffer
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* Copyright (C) 1995-2003 Jean-loup Gailly.
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* For conditions of distribution and use, see copyright notice in zlib.h
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*/
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/* @(#) $Id$ */
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#define ZLIB_INTERNAL
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#include "zlib.h"
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/* ===========================================================================
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Decompresses the source buffer into the destination buffer. sourceLen is
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the byte length of the source buffer. Upon entry, destLen is the total
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size of the destination buffer, which must be large enough to hold the
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entire uncompressed data. (The size of the uncompressed data must have
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been saved previously by the compressor and transmitted to the decompressor
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by some mechanism outside the scope of this compression library.)
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Upon exit, destLen is the actual size of the compressed buffer.
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This function can be used to decompress a whole file at once if the
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input file is mmap'ed.
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uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
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enough memory, Z_BUF_ERROR if there was not enough room in the output
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buffer, or Z_DATA_ERROR if the input data was corrupted.
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*/
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int ZEXPORT uncompress (dest, destLen, source, sourceLen)
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Bytef *dest;
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uLongf *destLen;
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const Bytef *source;
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uLong sourceLen;
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{
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z_stream stream;
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int err;
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stream.next_in = (Bytef*)source;
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stream.avail_in = (uInt)sourceLen;
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/* Check for source > 64K on 16-bit machine: */
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if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
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stream.next_out = dest;
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stream.avail_out = (uInt)*destLen;
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if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
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stream.zalloc = (alloc_func)0;
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stream.zfree = (free_func)0;
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err = inflateInit(&stream);
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if (err != Z_OK) return err;
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err = inflate(&stream, Z_FINISH);
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if (err != Z_STREAM_END) {
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inflateEnd(&stream);
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if (err == Z_NEED_DICT || (err == Z_BUF_ERROR && stream.avail_in == 0))
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return Z_DATA_ERROR;
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return err;
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}
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*destLen = stream.total_out;
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err = inflateEnd(&stream);
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return err;
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}
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