600 lines
15 KiB
ObjectPascal
600 lines
15 KiB
ObjectPascal
(* example.c -- usage example of the zlib compression library
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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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* Pascal translation
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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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* Adaptation to the zlibpas interface
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* Copyright (C) 2003 by Cosmin Truta.
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* For conditions of distribution and use, see copyright notice in readme.txt
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*)
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program example;
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{$DEFINE TEST_COMPRESS}
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{DO NOT $DEFINE TEST_GZIO}
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{$DEFINE TEST_DEFLATE}
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{$DEFINE TEST_INFLATE}
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{$DEFINE TEST_FLUSH}
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{$DEFINE TEST_SYNC}
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{$DEFINE TEST_DICT}
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uses SysUtils, zlibpas;
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const TESTFILE = 'foo.gz';
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(* "hello world" would be more standard, but the repeated "hello"
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* stresses the compression code better, sorry...
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*)
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const hello: PChar = 'hello, hello!';
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const dictionary: PChar = 'hello';
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var dictId: LongInt; (* Adler32 value of the dictionary *)
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procedure CHECK_ERR(err: Integer; msg: String);
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begin
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if err <> Z_OK then
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begin
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WriteLn(msg, ' error: ', err);
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Halt(1);
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end;
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end;
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procedure EXIT_ERR(const msg: String);
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begin
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WriteLn('Error: ', msg);
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Halt(1);
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end;
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(* ===========================================================================
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* Test compress and uncompress
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*)
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{$IFDEF TEST_COMPRESS}
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procedure test_compress(compr: Pointer; comprLen: LongInt;
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uncompr: Pointer; uncomprLen: LongInt);
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var err: Integer;
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len: LongInt;
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begin
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len := StrLen(hello)+1;
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err := compress(compr, comprLen, hello, len);
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CHECK_ERR(err, 'compress');
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StrCopy(PChar(uncompr), 'garbage');
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err := uncompress(uncompr, uncomprLen, compr, comprLen);
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CHECK_ERR(err, 'uncompress');
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if StrComp(PChar(uncompr), hello) <> 0 then
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EXIT_ERR('bad uncompress')
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else
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WriteLn('uncompress(): ', PChar(uncompr));
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test read/write of .gz files
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*)
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{$IFDEF TEST_GZIO}
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procedure test_gzio(const fname: PChar; (* compressed file name *)
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uncompr: Pointer;
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uncomprLen: LongInt);
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var err: Integer;
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len: Integer;
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zfile: gzFile;
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pos: LongInt;
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begin
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len := StrLen(hello)+1;
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zfile := gzopen(fname, 'wb');
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if zfile = NIL then
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begin
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WriteLn('gzopen error');
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Halt(1);
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end;
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gzputc(zfile, 'h');
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if gzputs(zfile, 'ello') <> 4 then
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begin
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WriteLn('gzputs err: ', gzerror(zfile, err));
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Halt(1);
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end;
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{$IFDEF GZ_FORMAT_STRING}
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if gzprintf(zfile, ', %s!', 'hello') <> 8 then
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begin
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WriteLn('gzprintf err: ', gzerror(zfile, err));
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Halt(1);
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end;
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{$ELSE}
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if gzputs(zfile, ', hello!') <> 8 then
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begin
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WriteLn('gzputs err: ', gzerror(zfile, err));
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Halt(1);
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end;
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{$ENDIF}
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gzseek(zfile, 1, SEEK_CUR); (* add one zero byte *)
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gzclose(zfile);
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zfile := gzopen(fname, 'rb');
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if zfile = NIL then
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begin
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WriteLn('gzopen error');
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Halt(1);
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end;
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StrCopy(PChar(uncompr), 'garbage');
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if gzread(zfile, uncompr, uncomprLen) <> len then
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begin
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WriteLn('gzread err: ', gzerror(zfile, err));
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Halt(1);
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end;
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if StrComp(PChar(uncompr), hello) <> 0 then
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begin
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WriteLn('bad gzread: ', PChar(uncompr));
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Halt(1);
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end
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else
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WriteLn('gzread(): ', PChar(uncompr));
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pos := gzseek(zfile, -8, SEEK_CUR);
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if (pos <> 6) or (gztell(zfile) <> pos) then
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begin
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WriteLn('gzseek error, pos=', pos, ', gztell=', gztell(zfile));
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Halt(1);
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end;
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if gzgetc(zfile) <> ' ' then
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begin
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WriteLn('gzgetc error');
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Halt(1);
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end;
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if gzungetc(' ', zfile) <> ' ' then
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begin
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WriteLn('gzungetc error');
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Halt(1);
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end;
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gzgets(zfile, PChar(uncompr), uncomprLen);
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uncomprLen := StrLen(PChar(uncompr));
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if uncomprLen <> 7 then (* " hello!" *)
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begin
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WriteLn('gzgets err after gzseek: ', gzerror(zfile, err));
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Halt(1);
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end;
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if StrComp(PChar(uncompr), hello + 6) <> 0 then
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begin
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WriteLn('bad gzgets after gzseek');
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Halt(1);
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end
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else
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WriteLn('gzgets() after gzseek: ', PChar(uncompr));
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gzclose(zfile);
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test deflate with small buffers
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*)
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{$IFDEF TEST_DEFLATE}
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procedure test_deflate(compr: Pointer; comprLen: LongInt);
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var c_stream: z_stream; (* compression stream *)
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err: Integer;
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len: LongInt;
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begin
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len := StrLen(hello)+1;
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c_stream.zalloc := NIL;
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c_stream.zfree := NIL;
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c_stream.opaque := NIL;
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err := deflateInit(c_stream, Z_DEFAULT_COMPRESSION);
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CHECK_ERR(err, 'deflateInit');
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c_stream.next_in := hello;
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c_stream.next_out := compr;
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while (c_stream.total_in <> len) and
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(c_stream.total_out < comprLen) do
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begin
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c_stream.avail_out := 1; { force small buffers }
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c_stream.avail_in := 1;
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err := deflate(c_stream, Z_NO_FLUSH);
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CHECK_ERR(err, 'deflate');
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end;
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(* Finish the stream, still forcing small buffers: *)
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while TRUE do
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begin
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c_stream.avail_out := 1;
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err := deflate(c_stream, Z_FINISH);
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if err = Z_STREAM_END then
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break;
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CHECK_ERR(err, 'deflate');
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end;
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err := deflateEnd(c_stream);
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CHECK_ERR(err, 'deflateEnd');
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test inflate with small buffers
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*)
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{$IFDEF TEST_INFLATE}
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procedure test_inflate(compr: Pointer; comprLen : LongInt;
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uncompr: Pointer; uncomprLen : LongInt);
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var err: Integer;
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d_stream: z_stream; (* decompression stream *)
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begin
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StrCopy(PChar(uncompr), 'garbage');
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d_stream.zalloc := NIL;
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d_stream.zfree := NIL;
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d_stream.opaque := NIL;
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d_stream.next_in := compr;
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d_stream.avail_in := 0;
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d_stream.next_out := uncompr;
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err := inflateInit(d_stream);
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CHECK_ERR(err, 'inflateInit');
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while (d_stream.total_out < uncomprLen) and
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(d_stream.total_in < comprLen) do
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begin
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d_stream.avail_out := 1; (* force small buffers *)
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d_stream.avail_in := 1;
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err := inflate(d_stream, Z_NO_FLUSH);
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if err = Z_STREAM_END then
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break;
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CHECK_ERR(err, 'inflate');
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end;
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err := inflateEnd(d_stream);
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CHECK_ERR(err, 'inflateEnd');
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if StrComp(PChar(uncompr), hello) <> 0 then
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EXIT_ERR('bad inflate')
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else
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WriteLn('inflate(): ', PChar(uncompr));
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test deflate with large buffers and dynamic change of compression level
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*)
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{$IFDEF TEST_DEFLATE}
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procedure test_large_deflate(compr: Pointer; comprLen: LongInt;
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uncompr: Pointer; uncomprLen: LongInt);
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var c_stream: z_stream; (* compression stream *)
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err: Integer;
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begin
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c_stream.zalloc := NIL;
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c_stream.zfree := NIL;
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c_stream.opaque := NIL;
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err := deflateInit(c_stream, Z_BEST_SPEED);
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CHECK_ERR(err, 'deflateInit');
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c_stream.next_out := compr;
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c_stream.avail_out := Integer(comprLen);
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(* At this point, uncompr is still mostly zeroes, so it should compress
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* very well:
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*)
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c_stream.next_in := uncompr;
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c_stream.avail_in := Integer(uncomprLen);
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err := deflate(c_stream, Z_NO_FLUSH);
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CHECK_ERR(err, 'deflate');
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if c_stream.avail_in <> 0 then
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EXIT_ERR('deflate not greedy');
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(* Feed in already compressed data and switch to no compression: *)
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deflateParams(c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
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c_stream.next_in := compr;
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c_stream.avail_in := Integer(comprLen div 2);
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err := deflate(c_stream, Z_NO_FLUSH);
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CHECK_ERR(err, 'deflate');
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(* Switch back to compressing mode: *)
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deflateParams(c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
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c_stream.next_in := uncompr;
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c_stream.avail_in := Integer(uncomprLen);
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err := deflate(c_stream, Z_NO_FLUSH);
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CHECK_ERR(err, 'deflate');
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err := deflate(c_stream, Z_FINISH);
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if err <> Z_STREAM_END then
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EXIT_ERR('deflate should report Z_STREAM_END');
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err := deflateEnd(c_stream);
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CHECK_ERR(err, 'deflateEnd');
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test inflate with large buffers
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*)
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{$IFDEF TEST_INFLATE}
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procedure test_large_inflate(compr: Pointer; comprLen: LongInt;
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uncompr: Pointer; uncomprLen: LongInt);
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var err: Integer;
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d_stream: z_stream; (* decompression stream *)
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begin
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StrCopy(PChar(uncompr), 'garbage');
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d_stream.zalloc := NIL;
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d_stream.zfree := NIL;
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d_stream.opaque := NIL;
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d_stream.next_in := compr;
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d_stream.avail_in := Integer(comprLen);
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err := inflateInit(d_stream);
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CHECK_ERR(err, 'inflateInit');
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while TRUE do
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begin
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d_stream.next_out := uncompr; (* discard the output *)
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d_stream.avail_out := Integer(uncomprLen);
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err := inflate(d_stream, Z_NO_FLUSH);
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if err = Z_STREAM_END then
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break;
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CHECK_ERR(err, 'large inflate');
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end;
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err := inflateEnd(d_stream);
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CHECK_ERR(err, 'inflateEnd');
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if d_stream.total_out <> 2 * uncomprLen + comprLen div 2 then
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begin
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WriteLn('bad large inflate: ', d_stream.total_out);
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Halt(1);
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end
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else
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WriteLn('large_inflate(): OK');
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test deflate with full flush
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*)
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{$IFDEF TEST_FLUSH}
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procedure test_flush(compr: Pointer; var comprLen : LongInt);
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var c_stream: z_stream; (* compression stream *)
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err: Integer;
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len: Integer;
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begin
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len := StrLen(hello)+1;
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c_stream.zalloc := NIL;
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c_stream.zfree := NIL;
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c_stream.opaque := NIL;
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err := deflateInit(c_stream, Z_DEFAULT_COMPRESSION);
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CHECK_ERR(err, 'deflateInit');
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c_stream.next_in := hello;
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c_stream.next_out := compr;
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c_stream.avail_in := 3;
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c_stream.avail_out := Integer(comprLen);
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err := deflate(c_stream, Z_FULL_FLUSH);
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CHECK_ERR(err, 'deflate');
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Inc(PByteArray(compr)^[3]); (* force an error in first compressed block *)
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c_stream.avail_in := len - 3;
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err := deflate(c_stream, Z_FINISH);
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if err <> Z_STREAM_END then
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CHECK_ERR(err, 'deflate');
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err := deflateEnd(c_stream);
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CHECK_ERR(err, 'deflateEnd');
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comprLen := c_stream.total_out;
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test inflateSync()
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*)
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{$IFDEF TEST_SYNC}
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procedure test_sync(compr: Pointer; comprLen: LongInt;
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uncompr: Pointer; uncomprLen : LongInt);
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var err: Integer;
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d_stream: z_stream; (* decompression stream *)
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begin
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StrCopy(PChar(uncompr), 'garbage');
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d_stream.zalloc := NIL;
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d_stream.zfree := NIL;
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d_stream.opaque := NIL;
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d_stream.next_in := compr;
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d_stream.avail_in := 2; (* just read the zlib header *)
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err := inflateInit(d_stream);
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CHECK_ERR(err, 'inflateInit');
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d_stream.next_out := uncompr;
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d_stream.avail_out := Integer(uncomprLen);
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inflate(d_stream, Z_NO_FLUSH);
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CHECK_ERR(err, 'inflate');
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d_stream.avail_in := Integer(comprLen-2); (* read all compressed data *)
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err := inflateSync(d_stream); (* but skip the damaged part *)
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CHECK_ERR(err, 'inflateSync');
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err := inflate(d_stream, Z_FINISH);
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if err <> Z_DATA_ERROR then
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EXIT_ERR('inflate should report DATA_ERROR');
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(* Because of incorrect adler32 *)
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err := inflateEnd(d_stream);
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CHECK_ERR(err, 'inflateEnd');
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WriteLn('after inflateSync(): hel', PChar(uncompr));
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test deflate with preset dictionary
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*)
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{$IFDEF TEST_DICT}
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procedure test_dict_deflate(compr: Pointer; comprLen: LongInt);
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var c_stream: z_stream; (* compression stream *)
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err: Integer;
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begin
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c_stream.zalloc := NIL;
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c_stream.zfree := NIL;
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c_stream.opaque := NIL;
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err := deflateInit(c_stream, Z_BEST_COMPRESSION);
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CHECK_ERR(err, 'deflateInit');
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err := deflateSetDictionary(c_stream, dictionary, StrLen(dictionary));
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CHECK_ERR(err, 'deflateSetDictionary');
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dictId := c_stream.adler;
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c_stream.next_out := compr;
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c_stream.avail_out := Integer(comprLen);
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c_stream.next_in := hello;
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c_stream.avail_in := StrLen(hello)+1;
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err := deflate(c_stream, Z_FINISH);
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if err <> Z_STREAM_END then
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EXIT_ERR('deflate should report Z_STREAM_END');
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err := deflateEnd(c_stream);
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CHECK_ERR(err, 'deflateEnd');
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end;
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{$ENDIF}
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(* ===========================================================================
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* Test inflate with a preset dictionary
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*)
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{$IFDEF TEST_DICT}
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procedure test_dict_inflate(compr: Pointer; comprLen: LongInt;
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uncompr: Pointer; uncomprLen: LongInt);
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var err: Integer;
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d_stream: z_stream; (* decompression stream *)
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begin
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StrCopy(PChar(uncompr), 'garbage');
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d_stream.zalloc := NIL;
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d_stream.zfree := NIL;
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d_stream.opaque := NIL;
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d_stream.next_in := compr;
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d_stream.avail_in := Integer(comprLen);
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err := inflateInit(d_stream);
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CHECK_ERR(err, 'inflateInit');
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d_stream.next_out := uncompr;
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d_stream.avail_out := Integer(uncomprLen);
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while TRUE do
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begin
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err := inflate(d_stream, Z_NO_FLUSH);
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if err = Z_STREAM_END then
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break;
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if err = Z_NEED_DICT then
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begin
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if d_stream.adler <> dictId then
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EXIT_ERR('unexpected dictionary');
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err := inflateSetDictionary(d_stream, dictionary, StrLen(dictionary));
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end;
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CHECK_ERR(err, 'inflate with dict');
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end;
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err := inflateEnd(d_stream);
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CHECK_ERR(err, 'inflateEnd');
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if StrComp(PChar(uncompr), hello) <> 0 then
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EXIT_ERR('bad inflate with dict')
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else
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WriteLn('inflate with dictionary: ', PChar(uncompr));
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end;
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{$ENDIF}
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var compr, uncompr: Pointer;
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comprLen, uncomprLen: LongInt;
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begin
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if zlibVersion^ <> ZLIB_VERSION[1] then
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EXIT_ERR('Incompatible zlib version');
|
|
|
|
WriteLn('zlib version: ', zlibVersion);
|
|
WriteLn('zlib compile flags: ', Format('0x%x', [zlibCompileFlags]));
|
|
|
|
comprLen := 10000 * SizeOf(Integer); (* don't overflow on MSDOS *)
|
|
uncomprLen := comprLen;
|
|
GetMem(compr, comprLen);
|
|
GetMem(uncompr, uncomprLen);
|
|
if (compr = NIL) or (uncompr = NIL) then
|
|
EXIT_ERR('Out of memory');
|
|
(* compr and uncompr are cleared to avoid reading uninitialized
|
|
* data and to ensure that uncompr compresses well.
|
|
*)
|
|
FillChar(compr^, comprLen, 0);
|
|
FillChar(uncompr^, uncomprLen, 0);
|
|
|
|
{$IFDEF TEST_COMPRESS}
|
|
WriteLn('** Testing compress');
|
|
test_compress(compr, comprLen, uncompr, uncomprLen);
|
|
{$ENDIF}
|
|
|
|
{$IFDEF TEST_GZIO}
|
|
WriteLn('** Testing gzio');
|
|
if ParamCount >= 1 then
|
|
test_gzio(ParamStr(1), uncompr, uncomprLen)
|
|
else
|
|
test_gzio(TESTFILE, uncompr, uncomprLen);
|
|
{$ENDIF}
|
|
|
|
{$IFDEF TEST_DEFLATE}
|
|
WriteLn('** Testing deflate with small buffers');
|
|
test_deflate(compr, comprLen);
|
|
{$ENDIF}
|
|
{$IFDEF TEST_INFLATE}
|
|
WriteLn('** Testing inflate with small buffers');
|
|
test_inflate(compr, comprLen, uncompr, uncomprLen);
|
|
{$ENDIF}
|
|
|
|
{$IFDEF TEST_DEFLATE}
|
|
WriteLn('** Testing deflate with large buffers');
|
|
test_large_deflate(compr, comprLen, uncompr, uncomprLen);
|
|
{$ENDIF}
|
|
{$IFDEF TEST_INFLATE}
|
|
WriteLn('** Testing inflate with large buffers');
|
|
test_large_inflate(compr, comprLen, uncompr, uncomprLen);
|
|
{$ENDIF}
|
|
|
|
{$IFDEF TEST_FLUSH}
|
|
WriteLn('** Testing deflate with full flush');
|
|
test_flush(compr, comprLen);
|
|
{$ENDIF}
|
|
{$IFDEF TEST_SYNC}
|
|
WriteLn('** Testing inflateSync');
|
|
test_sync(compr, comprLen, uncompr, uncomprLen);
|
|
{$ENDIF}
|
|
comprLen := uncomprLen;
|
|
|
|
{$IFDEF TEST_DICT}
|
|
WriteLn('** Testing deflate and inflate with preset dictionary');
|
|
test_dict_deflate(compr, comprLen);
|
|
test_dict_inflate(compr, comprLen, uncompr, uncomprLen);
|
|
{$ENDIF}
|
|
|
|
FreeMem(compr, comprLen);
|
|
FreeMem(uncompr, uncomprLen);
|
|
end.
|