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93 lines
2.4 KiB
ObjectPascal
93 lines
2.4 KiB
ObjectPascal
Unit zUnCompr;
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{ uncompr.c -- decompress a memory buffer
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Copyright (C) 1995-1998 Jean-loup Gailly.
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Pascal tranlastion
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Copyright (C) 1998 by Jacques Nomssi Nzali
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For conditions of distribution and use, see copyright notice in readme.txt
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}
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interface
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{$I zconf.inc}
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uses
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zutil, zbase, zInflate;
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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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function uncompress (dest : pBytef;
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var destLen : uLong;
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source : pBytef;
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sourceLen : uLong) : int;
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implementation
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function uncompress (dest : pBytef;
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var destLen : uLong;
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source : pBytef;
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sourceLen : uLong) : int;
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var
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stream : z_stream;
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err : int;
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begin
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stream.next_in := 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) then
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begin
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uncompress := Z_BUF_ERROR;
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exit;
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end;
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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) then
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begin
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uncompress := Z_BUF_ERROR;
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exit;
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end;
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stream.zalloc := NIL; { alloc_func(0); }
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stream.zfree := NIL; { free_func(0); }
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err := inflateInit(stream);
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if (err <> Z_OK) then
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begin
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uncompress := err;
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exit;
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end;
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err := inflate(stream, Z_FINISH);
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if (err <> Z_STREAM_END) then
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begin
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inflateEnd(stream);
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if err = Z_OK then
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uncompress := Z_BUF_ERROR
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else
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uncompress := err;
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exit;
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end;
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destLen := stream.total_out;
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err := inflateEnd(stream);
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uncompress := err;
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end;
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end.
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