You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
599 lines
15 KiB
599 lines
15 KiB
(* 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.
|
|
|