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Diffstat (limited to 'zlib/contrib/pascal/example.pas')
-rw-r--r-- | zlib/contrib/pascal/example.pas | 599 |
1 files changed, 599 insertions, 0 deletions
diff --git a/zlib/contrib/pascal/example.pas b/zlib/contrib/pascal/example.pas new file mode 100644 index 000000000..5518b36a7 --- /dev/null +++ b/zlib/contrib/pascal/example.pas @@ -0,0 +1,599 @@ +(* example.c -- usage example of the zlib compression library + * Copyright (C) 1995-2003 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + * + * Pascal translation + * Copyright (C) 1998 by Jacques Nomssi Nzali. + * For conditions of distribution and use, see copyright notice in readme.txt + * + * Adaptation to the zlibpas interface + * Copyright (C) 2003 by Cosmin Truta. + * For conditions of distribution and use, see copyright notice in readme.txt + *) + +program example; + +{$DEFINE TEST_COMPRESS} +{DO NOT $DEFINE TEST_GZIO} +{$DEFINE TEST_DEFLATE} +{$DEFINE TEST_INFLATE} +{$DEFINE TEST_FLUSH} +{$DEFINE TEST_SYNC} +{$DEFINE TEST_DICT} + +uses SysUtils, zlibpas; + +const TESTFILE = 'foo.gz'; + +(* "hello world" would be more standard, but the repeated "hello" + * stresses the compression code better, sorry... + *) +const hello: PChar = 'hello, hello!'; + +const dictionary: PChar = 'hello'; + +var dictId: LongInt; (* Adler32 value of the dictionary *) + +procedure CHECK_ERR(err: Integer; msg: String); +begin + if err <> Z_OK then + begin + WriteLn(msg, ' error: ', err); + Halt(1); + end; +end; + +procedure EXIT_ERR(const msg: String); +begin + WriteLn('Error: ', msg); + Halt(1); +end; + +(* =========================================================================== + * Test compress and uncompress + *) +{$IFDEF TEST_COMPRESS} +procedure test_compress(compr: Pointer; comprLen: LongInt; + uncompr: Pointer; uncomprLen: LongInt); +var err: Integer; + len: LongInt; +begin + len := StrLen(hello)+1; + + err := compress(compr, comprLen, hello, len); + CHECK_ERR(err, 'compress'); + + StrCopy(PChar(uncompr), 'garbage'); + + err := uncompress(uncompr, uncomprLen, compr, comprLen); + CHECK_ERR(err, 'uncompress'); + + if StrComp(PChar(uncompr), hello) <> 0 then + EXIT_ERR('bad uncompress') + else + WriteLn('uncompress(): ', PChar(uncompr)); +end; +{$ENDIF} + +(* =========================================================================== + * Test read/write of .gz files + *) +{$IFDEF TEST_GZIO} +procedure test_gzio(const fname: PChar; (* compressed file name *) + uncompr: Pointer; + uncomprLen: LongInt); +var err: Integer; + len: Integer; + zfile: gzFile; + pos: LongInt; +begin + len := StrLen(hello)+1; + + zfile := gzopen(fname, 'wb'); + if zfile = NIL then + begin + WriteLn('gzopen error'); + Halt(1); + end; + gzputc(zfile, 'h'); + if gzputs(zfile, 'ello') <> 4 then + begin + WriteLn('gzputs err: ', gzerror(zfile, err)); + Halt(1); + end; + {$IFDEF GZ_FORMAT_STRING} + if gzprintf(zfile, ', %s!', 'hello') <> 8 then + begin + WriteLn('gzprintf err: ', gzerror(zfile, err)); + Halt(1); + end; + {$ELSE} + if gzputs(zfile, ', hello!') <> 8 then + begin + WriteLn('gzputs err: ', gzerror(zfile, err)); + Halt(1); + end; + {$ENDIF} + gzseek(zfile, 1, SEEK_CUR); (* add one zero byte *) + gzclose(zfile); + + zfile := gzopen(fname, 'rb'); + if zfile = NIL then + begin + WriteLn('gzopen error'); + Halt(1); + end; + + StrCopy(PChar(uncompr), 'garbage'); + + if gzread(zfile, uncompr, uncomprLen) <> len then + begin + WriteLn('gzread err: ', gzerror(zfile, err)); + Halt(1); + end; + if StrComp(PChar(uncompr), hello) <> 0 then + begin + WriteLn('bad gzread: ', PChar(uncompr)); + Halt(1); + end + else + WriteLn('gzread(): ', PChar(uncompr)); + + pos := gzseek(zfile, -8, SEEK_CUR); + if (pos <> 6) or (gztell(zfile) <> pos) then + begin + WriteLn('gzseek error, pos=', pos, ', gztell=', gztell(zfile)); + Halt(1); + end; + + if gzgetc(zfile) <> ' ' then + begin + WriteLn('gzgetc error'); + Halt(1); + end; + + if gzungetc(' ', zfile) <> ' ' then + begin + WriteLn('gzungetc error'); + Halt(1); + end; + + gzgets(zfile, PChar(uncompr), uncomprLen); + uncomprLen := StrLen(PChar(uncompr)); + if uncomprLen <> 7 then (* " hello!" *) + begin + WriteLn('gzgets err after gzseek: ', gzerror(zfile, err)); + Halt(1); + end; + if StrComp(PChar(uncompr), hello + 6) <> 0 then + begin + WriteLn('bad gzgets after gzseek'); + Halt(1); + end + else + WriteLn('gzgets() after gzseek: ', PChar(uncompr)); + + gzclose(zfile); +end; +{$ENDIF} + +(* =========================================================================== + * Test deflate with small buffers + *) +{$IFDEF TEST_DEFLATE} +procedure test_deflate(compr: Pointer; comprLen: LongInt); +var c_stream: z_stream; (* compression stream *) + err: Integer; + len: LongInt; +begin + len := StrLen(hello)+1; + + c_stream.zalloc := NIL; + c_stream.zfree := NIL; + c_stream.opaque := NIL; + + err := deflateInit(c_stream, Z_DEFAULT_COMPRESSION); + CHECK_ERR(err, 'deflateInit'); + + c_stream.next_in := hello; + c_stream.next_out := compr; + + while (c_stream.total_in <> len) and + (c_stream.total_out < comprLen) do + begin + c_stream.avail_out := 1; { force small buffers } + c_stream.avail_in := 1; + err := deflate(c_stream, Z_NO_FLUSH); + CHECK_ERR(err, 'deflate'); + end; + + (* Finish the stream, still forcing small buffers: *) + while TRUE do + begin + c_stream.avail_out := 1; + err := deflate(c_stream, Z_FINISH); + if err = Z_STREAM_END then + break; + CHECK_ERR(err, 'deflate'); + end; + + err := deflateEnd(c_stream); + CHECK_ERR(err, 'deflateEnd'); +end; +{$ENDIF} + +(* =========================================================================== + * Test inflate with small buffers + *) +{$IFDEF TEST_INFLATE} +procedure test_inflate(compr: Pointer; comprLen : LongInt; + uncompr: Pointer; uncomprLen : LongInt); +var err: Integer; + d_stream: z_stream; (* decompression stream *) +begin + StrCopy(PChar(uncompr), 'garbage'); + + d_stream.zalloc := NIL; + d_stream.zfree := NIL; + d_stream.opaque := NIL; + + d_stream.next_in := compr; + d_stream.avail_in := 0; + d_stream.next_out := uncompr; + + err := inflateInit(d_stream); + CHECK_ERR(err, 'inflateInit'); + + while (d_stream.total_out < uncomprLen) and + (d_stream.total_in < comprLen) do + begin + d_stream.avail_out := 1; (* force small buffers *) + d_stream.avail_in := 1; + err := inflate(d_stream, Z_NO_FLUSH); + if err = Z_STREAM_END then + break; + CHECK_ERR(err, 'inflate'); + end; + + err := inflateEnd(d_stream); + CHECK_ERR(err, 'inflateEnd'); + + if StrComp(PChar(uncompr), hello) <> 0 then + EXIT_ERR('bad inflate') + else + WriteLn('inflate(): ', PChar(uncompr)); +end; +{$ENDIF} + +(* =========================================================================== + * Test deflate with large buffers and dynamic change of compression level + *) +{$IFDEF TEST_DEFLATE} +procedure test_large_deflate(compr: Pointer; comprLen: LongInt; + uncompr: Pointer; uncomprLen: LongInt); +var c_stream: z_stream; (* compression stream *) + err: Integer; +begin + c_stream.zalloc := NIL; + c_stream.zfree := NIL; + c_stream.opaque := NIL; + + err := deflateInit(c_stream, Z_BEST_SPEED); + CHECK_ERR(err, 'deflateInit'); + + c_stream.next_out := compr; + c_stream.avail_out := Integer(comprLen); + + (* At this point, uncompr is still mostly zeroes, so it should compress + * very well: + *) + c_stream.next_in := uncompr; + c_stream.avail_in := Integer(uncomprLen); + err := deflate(c_stream, Z_NO_FLUSH); + CHECK_ERR(err, 'deflate'); + if c_stream.avail_in <> 0 then + EXIT_ERR('deflate not greedy'); + + (* Feed in already compressed data and switch to no compression: *) + deflateParams(c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY); + c_stream.next_in := compr; + c_stream.avail_in := Integer(comprLen div 2); + err := deflate(c_stream, Z_NO_FLUSH); + CHECK_ERR(err, 'deflate'); + + (* Switch back to compressing mode: *) + deflateParams(c_stream, Z_BEST_COMPRESSION, Z_FILTERED); + c_stream.next_in := uncompr; + c_stream.avail_in := Integer(uncomprLen); + err := deflate(c_stream, Z_NO_FLUSH); + CHECK_ERR(err, 'deflate'); + + err := deflate(c_stream, Z_FINISH); + if err <> Z_STREAM_END then + EXIT_ERR('deflate should report Z_STREAM_END'); + + err := deflateEnd(c_stream); + CHECK_ERR(err, 'deflateEnd'); +end; +{$ENDIF} + +(* =========================================================================== + * Test inflate with large buffers + *) +{$IFDEF TEST_INFLATE} +procedure test_large_inflate(compr: Pointer; comprLen: LongInt; + uncompr: Pointer; uncomprLen: LongInt); +var err: Integer; + d_stream: z_stream; (* decompression stream *) +begin + StrCopy(PChar(uncompr), 'garbage'); + + d_stream.zalloc := NIL; + d_stream.zfree := NIL; + d_stream.opaque := NIL; + + d_stream.next_in := compr; + d_stream.avail_in := Integer(comprLen); + + err := inflateInit(d_stream); + CHECK_ERR(err, 'inflateInit'); + + while TRUE do + begin + d_stream.next_out := uncompr; (* discard the output *) + d_stream.avail_out := Integer(uncomprLen); + err := inflate(d_stream, Z_NO_FLUSH); + if err = Z_STREAM_END then + break; + CHECK_ERR(err, 'large inflate'); + end; + + err := inflateEnd(d_stream); + CHECK_ERR(err, 'inflateEnd'); + + if d_stream.total_out <> 2 * uncomprLen + comprLen div 2 then + begin + WriteLn('bad large inflate: ', d_stream.total_out); + Halt(1); + end + else + WriteLn('large_inflate(): OK'); +end; +{$ENDIF} + +(* =========================================================================== + * Test deflate with full flush + *) +{$IFDEF TEST_FLUSH} +procedure test_flush(compr: Pointer; var comprLen : LongInt); +var c_stream: z_stream; (* compression stream *) + err: Integer; + len: Integer; +begin + len := StrLen(hello)+1; + + c_stream.zalloc := NIL; + c_stream.zfree := NIL; + c_stream.opaque := NIL; + + err := deflateInit(c_stream, Z_DEFAULT_COMPRESSION); + CHECK_ERR(err, 'deflateInit'); + + c_stream.next_in := hello; + c_stream.next_out := compr; + c_stream.avail_in := 3; + c_stream.avail_out := Integer(comprLen); + err := deflate(c_stream, Z_FULL_FLUSH); + CHECK_ERR(err, 'deflate'); + + Inc(PByteArray(compr)^[3]); (* force an error in first compressed block *) + c_stream.avail_in := len - 3; + + err := deflate(c_stream, Z_FINISH); + if err <> Z_STREAM_END then + CHECK_ERR(err, 'deflate'); + + err := deflateEnd(c_stream); + CHECK_ERR(err, 'deflateEnd'); + + comprLen := c_stream.total_out; +end; +{$ENDIF} + +(* =========================================================================== + * Test inflateSync() + *) +{$IFDEF TEST_SYNC} +procedure test_sync(compr: Pointer; comprLen: LongInt; + uncompr: Pointer; uncomprLen : LongInt); +var err: Integer; + d_stream: z_stream; (* decompression stream *) +begin + StrCopy(PChar(uncompr), 'garbage'); + + d_stream.zalloc := NIL; + d_stream.zfree := NIL; + d_stream.opaque := NIL; + + d_stream.next_in := compr; + d_stream.avail_in := 2; (* just read the zlib header *) + + err := inflateInit(d_stream); + CHECK_ERR(err, 'inflateInit'); + + d_stream.next_out := uncompr; + d_stream.avail_out := Integer(uncomprLen); + + inflate(d_stream, Z_NO_FLUSH); + CHECK_ERR(err, 'inflate'); + + d_stream.avail_in := Integer(comprLen-2); (* read all compressed data *) + err := inflateSync(d_stream); (* but skip the damaged part *) + CHECK_ERR(err, 'inflateSync'); + + err := inflate(d_stream, Z_FINISH); + if err <> Z_DATA_ERROR then + EXIT_ERR('inflate should report DATA_ERROR'); + (* Because of incorrect adler32 *) + + err := inflateEnd(d_stream); + CHECK_ERR(err, 'inflateEnd'); + + WriteLn('after inflateSync(): hel', PChar(uncompr)); +end; +{$ENDIF} + +(* =========================================================================== + * Test deflate with preset dictionary + *) +{$IFDEF TEST_DICT} +procedure test_dict_deflate(compr: Pointer; comprLen: LongInt); +var c_stream: z_stream; (* compression stream *) + err: Integer; +begin + c_stream.zalloc := NIL; + c_stream.zfree := NIL; + c_stream.opaque := NIL; + + err := deflateInit(c_stream, Z_BEST_COMPRESSION); + CHECK_ERR(err, 'deflateInit'); + + err := deflateSetDictionary(c_stream, dictionary, StrLen(dictionary)); + CHECK_ERR(err, 'deflateSetDictionary'); + + dictId := c_stream.adler; + c_stream.next_out := compr; + c_stream.avail_out := Integer(comprLen); + + c_stream.next_in := hello; + c_stream.avail_in := StrLen(hello)+1; + + err := deflate(c_stream, Z_FINISH); + if err <> Z_STREAM_END then + EXIT_ERR('deflate should report Z_STREAM_END'); + + err := deflateEnd(c_stream); + CHECK_ERR(err, 'deflateEnd'); +end; +{$ENDIF} + +(* =========================================================================== + * Test inflate with a preset dictionary + *) +{$IFDEF TEST_DICT} +procedure test_dict_inflate(compr: Pointer; comprLen: LongInt; + uncompr: Pointer; uncomprLen: LongInt); +var err: Integer; + d_stream: z_stream; (* decompression stream *) +begin + StrCopy(PChar(uncompr), 'garbage'); + + d_stream.zalloc := NIL; + d_stream.zfree := NIL; + d_stream.opaque := NIL; + + d_stream.next_in := compr; + d_stream.avail_in := Integer(comprLen); + + err := inflateInit(d_stream); + CHECK_ERR(err, 'inflateInit'); + + d_stream.next_out := uncompr; + d_stream.avail_out := Integer(uncomprLen); + + while TRUE do + begin + err := inflate(d_stream, Z_NO_FLUSH); + if err = Z_STREAM_END then + break; + if err = Z_NEED_DICT then + begin + if d_stream.adler <> dictId then + EXIT_ERR('unexpected dictionary'); + err := inflateSetDictionary(d_stream, dictionary, StrLen(dictionary)); + end; + CHECK_ERR(err, 'inflate with dict'); + end; + + err := inflateEnd(d_stream); + CHECK_ERR(err, 'inflateEnd'); + + if StrComp(PChar(uncompr), hello) <> 0 then + EXIT_ERR('bad inflate with dict') + else + WriteLn('inflate with dictionary: ', PChar(uncompr)); +end; +{$ENDIF} + +var compr, uncompr: Pointer; + comprLen, uncomprLen: LongInt; + +begin + if zlibVersion^ <> ZLIB_VERSION[1] then + EXIT_ERR('Incompatible zlib version'); + + WriteLn('zlib version: ', zlibVersion); + WriteLn('zlib compile flags: ', Format('0x%x', [zlibCompileFlags])); + + comprLen := 10000 * SizeOf(Integer); (* don't overflow on MSDOS *) + uncomprLen := comprLen; + GetMem(compr, comprLen); + GetMem(uncompr, uncomprLen); + if (compr = NIL) or (uncompr = NIL) then + EXIT_ERR('Out of memory'); + (* compr and uncompr are cleared to avoid reading uninitialized + * data and to ensure that uncompr compresses well. + *) + FillChar(compr^, comprLen, 0); + FillChar(uncompr^, uncomprLen, 0); + + {$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. |