lasarus_compotents/fwzip/zlib_external.pas

982 lines
31 KiB
ObjectPascal

{*****************************************************************************
* ZLib.pas (zlib 1.2.3) *
* *
* copyright (c) 2002-2005 Roberto Della Pasqua (www.dellapasqua.com) *
* copyright (c) 2000-2002 base2 technologies (www.base2ti.com) *
* copyright (c) 1997 Borland International (www.borland.com) *
* *
* revision history *
* 2008.02.15 updated to be interface compatible with old codegear zlib *
* while not changing new zlib 1.2.3 interface *
* 2006.04.21 updated with latest Borland C++ 2006 SP2 *
* 2005.02.03 updated with latest zlib 1.2.2, thanks to Fabio Dell'Aria *
* (www.eurekalog.com) for provide me the compiled objects *
* zlib is compiled without crc32-compressBound *
* 2003.12.18 updated with latest zlib 1.2.1 (see www.zlib.org) *
* obj's compiled with fastest speed optimizations (bcc 5.6.4) *
* (hint:see basm newsgroup about a Move RTL fast replacement) *
* Thanks to Cosmin Truta for the pascal zlib reference *
* *
* 2002.11.02 ZSendToBrowser: deflate algorithm for HTTP1.1 compression *
* 2002.10.24 ZFastCompressString and ZFastDecompressString:300% faster *
* 2002.10.15 recompiled zlib 1.1.4 c sources with speed optimizations *
* (and targeting 686+ cpu) and changes to accomodate Borland *
* standards (C++ v5.6 compiler) *
* 2002.10.15 optimized move mem for not aligned structures (strings,etc)*
* 2002.10.15 little changes to avoid system unique string calls *
* *
* 2002.03.15 updated to zlib version 1.1.4 *
* 2001.11.27 enhanced TZDecompressionStream.Read to adjust source *
* stream position upon end of compression data *
* fixed endless loop in TZDecompressionStream.Read when *
* destination count was greater than uncompressed data *
* 2001.10.26 renamed unit to integrate "nicely" with delphi 6 *
* 2000.11.24 added soFromEnd condition to TZDecompressionStream.Seek *
* added ZCompressStream and ZDecompressStream *
* 2000.06.13 optimized, fixed, rewrote, and enhanced the zlib.pas unit *
* included on the delphi cd (zlib version 1.1.3) *
* *
* acknowledgements *
* erik turner Z*Stream routines *
* david bennion finding the nastly little endless loop quirk with the *
* TZDecompressionStream.Read method *
* burak kalayci informing me about the zlib 1.1.4 update *
*****************************************************************************}
unit zlib_external deprecated;
{$MESSAGE WARN 'Модуль zlib_external устарел, ипользуйте директиву USE_ZLIB_EX и обновленные модули ZLib, см. пункт 11 Readme.txt'}
interface
uses
Windows,
Sysutils,
Classes;
const
ZLIB_VERSION = '1.2.3'; //do not localize
type
{$IF NOT DEFINED(TBytes)}
TBytes = array of Byte;
{$IFEND}
TZAlloc = function(opaque: Pointer; items, size: Integer): Pointer;
TZFree = procedure(opaque, block: Pointer);
TZCompressionLevel = (zcNone, zcFastest, zcDefault, zcMax);
// CG: Define old enum for compression level
TCompressionLevel = (clNone = Integer(zcNone), clFastest, clDefault, clMax);
{** TZStreamRec ***********************************************************}
TZStreamRec = packed record
next_in: PAnsiChar; // next input byte
avail_in: Longint; // number of bytes available at next_in
total_in: Longint; // total nb of input bytes read so far
next_out: PAnsiChar; // next output byte should be put here
avail_out: Longint; // remaining free space at next_out
total_out: Longint; // total nb of bytes output so far
msg: PAnsiChar; // last error message, NULL if no error
state: Pointer; // not visible by applications
zalloc: TZAlloc; // used to allocate the internal state
zfree: TZFree; // used to free the internal state
opaque: Pointer; // private data object passed to zalloc and zfree
data_type: Integer; // best guess about the data type: ascii or binary
adler: Longint; // adler32 value of the uncompressed data
reserved: Longint; // reserved for future use
end;
{** TCustomZStream ********************************************************}
TCustomZStream = class(TStream)
private
FStream: TStream;
FStreamPos: Int64;
FOnProgress: TNotifyEvent;
FZStream: TZStreamRec;
FBuffer: array[Word] of AnsiChar;
protected
constructor Create(stream: TStream);
procedure DoProgress; dynamic;
property OnProgress: TNotifyEvent read FOnProgress write FOnProgress;
end;
// CG: Add alias of classname to old Zlib classname
TCustomZLibStream = TCustomZStream;
{** TZCompressionStream ***************************************************}
TZCompressionStream = class(TCustomZStream)
private
function GetCompressionRate: Single;
public
constructor Create(dest: TStream; compressionLevel: TZCompressionLevel = zcDefault); overload;
// CG: Add overloaded constructor for old parameter type and order
constructor Create(compressionLevel: TCompressionLevel; dest: TStream); overload;
destructor Destroy; override;
function Read(var buffer; count: Longint): Longint; override;
function Write(const buffer; count: Longint): Longint; override;
function Seek(offset: Longint; origin: Word): Longint; override;
property CompressionRate: Single read GetCompressionRate;
property OnProgress;
end;
// CG: Add alias of classname to old Zlib classname
TCompressionStream = TZCompressionStream;
{** TZDecompressionStream *************************************************}
TZDecompressionStream = class(TCustomZStream)
public
constructor Create(source: TStream);
destructor Destroy; override;
function Read(var buffer; count: Longint): Longint; override;
function Write(const buffer; count: Longint): Longint; override;
function Seek(offset: Longint; origin: Word): Longint; override;
property OnProgress;
end;
// CG: Add alias of classname to old Zlib classname
TDecompressionStream = TZDecompressionStream;
{** zlib public routines ****************************************************}
{*****************************************************************************
* ZCompress *
* *
* pre-conditions *
* inBuffer = pointer to uncompressed data *
* inSize = size of inBuffer (bytes) *
* outBuffer = pointer (unallocated) *
* level = compression level *
* *
* post-conditions *
* outBuffer = pointer to compressed data (allocated) *
* outSize = size of outBuffer (bytes) *
*****************************************************************************}
procedure ZCompress(const inBuffer: Pointer; inSize: Integer;
out outBuffer: Pointer; out outSize: Integer;
level: TZCompressionLevel = zcDefault); overload;
// CG: Add overload to take old enum type
procedure ZCompress(const inBuffer: Pointer; inSize: Integer;
out outBuffer: Pointer; out outSize: Integer;
level: TCompressionLevel); overload;
{$IF CompilerVersion >= 19}inline;{$IFEND}
{*****************************************************************************
* ZDecompress *
* *
* pre-conditions *
* inBuffer = pointer to compressed data *
* inSize = size of inBuffer (bytes) *
* outBuffer = pointer (unallocated) *
* outEstimate = estimated size of uncompressed data (bytes) *
* *
* post-conditions *
* outBuffer = pointer to decompressed data (allocated) *
* outSize = size of outBuffer (bytes) *
*****************************************************************************}
procedure ZDecompress(const inBuffer: Pointer; inSize: Integer;
out outBuffer: Pointer; out outSize: Integer; outEstimate: Integer = 0);
{** string routines *********************************************************}
function ZCompressStr(const s: string; level: TZCompressionLevel = zcDefault): TBytes; overload;
// CG: Add overload to take old enum type
function ZCompressStr(const s: string; level: TCompressionLevel): TBytes; overload;
{$IF CompilerVersion >= 19}inline;{$IFEND}
function ZDecompressStr(const s: TBytes): string;
{** stream routines *********************************************************}
procedure ZCompressStream(inStream, outStream: TStream;
level: TZCompressionLevel = zcDefault); overload;
// CG: Add overload to take old enum type
procedure ZCompressStream(inStream, outStream: TStream;
level: TCompressionLevel); overload;
{$IF CompilerVersion >= 19}inline;{$IFEND}
procedure ZDecompressStream(inStream, outStream: TStream);
// CG: Routines from old version of ZLib required for CodeGear backwards compatability
function zlibAllocMem(AppData: Pointer; Items, Size: Integer): Pointer;
procedure zlibFreeMem(AppData, Block: Pointer);
{** export routines ********************************************************}
function adler32(adler: LongInt; const buf: PChar; len: Integer): LongInt;
procedure MoveI32(const Source; var Dest; Count: Integer);
procedure ZSendToBrowser(var s: string);
function deflateInit_(var strm: TZStreamRec; level: Integer; version: PChar; recsize: Integer): Integer;
function DeflateInit2_(var strm: TZStreamRec; level: integer; method: integer; windowBits: integer; memLevel: integer; strategy: integer; version: PChar; recsize: integer): integer;
function deflate(var strm: TZStreamRec; flush: Integer): Integer;
function deflateEnd(var strm: TZStreamRec): Integer;
function inflateInit_(var strm: TZStreamRec; version: PChar; recsize: Integer): Integer;
function inflateInit2_(var strm: TZStreamRec; windowBits: integer; version: PChar; recsize: integer): integer;
function inflate(var strm: TZStreamRec; flush: Integer): Integer;
function inflateEnd(var strm: TZStreamRec): Integer;
function inflateReset(var strm: TZStreamRec): Integer;
type
EZLibError = class(Exception);
EZCompressionError = class(EZLibError);
EZDecompressionError = class(EZLibError);
const
{** flush constants *******************************************************}
Z_NO_FLUSH = 0;
Z_PARTIAL_FLUSH = 1;
Z_SYNC_FLUSH = 2;
Z_FULL_FLUSH = 3;
Z_FINISH = 4;
{** return codes **********************************************************}
Z_OK = 0;
Z_STREAM_END = 1;
Z_NEED_DICT = 2;
Z_ERRNO = (-1);
Z_STREAM_ERROR = (-2);
Z_DATA_ERROR = (-3);
Z_MEM_ERROR = (-4);
Z_BUF_ERROR = (-5);
Z_VERSION_ERROR = (-6);
{** compression levels ****************************************************}
Z_NO_COMPRESSION = 0;
Z_BEST_SPEED = 1;
Z_BEST_COMPRESSION = 9;
Z_DEFAULT_COMPRESSION = (-1);
{** compression strategies ************************************************}
Z_FILTERED = 1;
Z_HUFFMAN_ONLY = 2;
Z_DEFAULT_STRATEGY = 0;
{** data types ************************************************************}
Z_BINARY = 0;
Z_ASCII = 1;
Z_UNKNOWN = 2;
{** compression methods ***************************************************}
Z_DEFLATED = 8;
{** return code messages **************************************************}
_z_errmsg: array[0..9] of PChar = (
'need dictionary', // Z_NEED_DICT (2) //do not localize
'stream end', // Z_STREAM_END (1) //do not localize
'', // Z_OK (0) //do not localize
'file error', // Z_ERRNO (-1) //do not localize
'stream error', // Z_STREAM_ERROR (-2) //do not localize
'data error', // Z_DATA_ERROR (-3) //do not localize
'insufficient memory', // Z_MEM_ERROR (-4)//do not localize
'buffer error', // Z_BUF_ERROR (-5) //do not localize
'incompatible version', // Z_VERSION_ERROR (-6)//do not localize
''//do not localize
);
ZLevels: array[TZCompressionLevel] of Shortint = (
Z_NO_COMPRESSION,
Z_BEST_SPEED,
Z_DEFAULT_COMPRESSION,
Z_BEST_COMPRESSION
);
SZInvalid = 'Invalid ZStream operation!';
implementation
const
zlib_d2010 = 'zlib_d2010.dll';
//{** link zlib 1.2.3 **************************************************************}
//{** bcc32 -c -6 -O2 -Ve -X -pr -a8 -b -d -k- -vi -tWM -r -RT- -ff *.c **}
//
//{$L Zlib/adler32.obj}
//{$L Zlib/deflate.obj}
//{$L Zlib/infback.obj}
//{$L Zlib/inffast.obj}
//{$L Zlib/inflate.obj}
//{$L Zlib/inftrees.obj}
//{$L Zlib/trees.obj}
//{$L Zlib/compress.obj}
//{$L Zlib/crc32.obj}
{*****************************************************************************
* note: do not reorder the above -- doing so will result in external *
* functions being undefined *
*****************************************************************************}
{*********************** Peter Morris not aligned move **********************}
procedure MoveI32(const Source; var Dest; Count: Integer); register;
asm
cmp ECX,0
Je @JustQuit
push ESI
push EDI
mov ESI, EAX
mov EDI, EDX
@Loop:
Mov AL, [ESI]
Inc ESI
mov [EDI], AL
Inc EDI
Dec ECX
Jnz @Loop
pop EDI
pop ESI
@JustQuit:
end;
{****************************************************************************}
{** deflate routines ********************************************************}
function deflateInit_(var strm: TZStreamRec; level: Integer; version: PChar;
recsize: Integer): Integer; external zlib_d2010;
function DeflateInit2_(var strm: TZStreamRec; level: integer; method: integer; windowBits: integer;
memLevel: integer; strategy: integer; version: PChar; recsize: integer): integer; external zlib_d2010;
function deflate(var strm: TZStreamRec; flush: Integer): Integer;
external zlib_d2010;
function deflateEnd(var strm: TZStreamRec): Integer; external zlib_d2010;
{** inflate routines ********************************************************}
function inflateInit_(var strm: TZStreamRec; version: PChar;
recsize: Integer): Integer; external zlib_d2010;
function inflateInit2_(var strm: TZStreamRec; windowBits: integer;
version: PChar; recsize: integer): integer; external zlib_d2010;
function inflate(var strm: TZStreamRec; flush: Integer): Integer;
external zlib_d2010;
function inflateEnd(var strm: TZStreamRec): Integer; external zlib_d2010;
function inflateReset(var strm: TZStreamRec): Integer; external zlib_d2010;
{** utility routines *******************************************************}
function adler32; external zlib_d2010;
//function crc32; external;
//function compressBound; external;
{** zlib function implementations *******************************************}
function zcalloc(opaque: Pointer; items, size: Integer): Pointer;
begin
GetMem(result, items * size);
end;
procedure zcfree(opaque, block: Pointer);
begin
FreeMem(block);
end;
{** c function implementations **********************************************}
procedure _memset(p: Pointer; b: Byte; count: Integer); cdecl;
begin
FillChar(p^, count, b);
end;
procedure _memcpy(dest, source: Pointer; count: Integer); cdecl;
begin
Move(source^, dest^, count);
end;
function _malloc(Size: Integer): Pointer; cdecl;
begin
GetMem(Result, Size);
end;
procedure _free(Block: Pointer); cdecl;
begin
FreeMem(Block);
end;
{** custom zlib routines ****************************************************}
function DeflateInit(var stream: TZStreamRec; level: Integer): Integer;
begin
result := DeflateInit_(stream, level, ZLIB_VERSION, SizeOf(TZStreamRec));
end;
function DeflateInit2(var stream: TZStreamRec; level, method, windowBits,
memLevel, strategy: Integer): Integer;
begin
result := DeflateInit2_(stream, level, method, windowBits, memLevel, strategy, ZLIB_VERSION, SizeOf(TZStreamRec));
end;
function InflateInit(var stream: TZStreamRec): Integer;
begin
result := InflateInit_(stream, ZLIB_VERSION, SizeOf(TZStreamRec));
end;
function InflateInit2(var stream: TZStreamRec; windowBits: Integer): Integer;
begin
result := InflateInit2_(stream, windowBits, ZLIB_VERSION, SizeOf(TZStreamRec));
end;
{****************************************************************************}
function ZCompressCheck(code: Integer): Integer;
begin
result := code;
if code < 0 then
begin
raise EZCompressionError.Create(_z_errmsg[2 - code]);
end;
end;
function ZDecompressCheck(code: Integer): Integer;
begin
Result := code;
if code < 0 then
begin
raise EZDecompressionError.Create(_z_errmsg[2 - code]);
end;
end;
procedure ZCompress(const inBuffer: Pointer; inSize: Integer;
out outBuffer: Pointer; out outSize: Integer;
level: TZCompressionLevel);
const
delta = 256;
var
zstream: TZStreamRec;
begin
FillChar(zstream, SizeOf(TZStreamRec), 0);
outSize := ((inSize + (inSize div 10) + 12) + 255) and not 255;
GetMem(outBuffer, outSize);
try
zstream.next_in := inBuffer;
zstream.avail_in := inSize;
zstream.next_out := outBuffer;
zstream.avail_out := outSize;
ZCompressCheck(DeflateInit(zstream, ZLevels[level]));
try
while ZCompressCheck(deflate(zstream, Z_FINISH)) <> Z_STREAM_END do
begin
Inc(outSize, delta);
ReallocMem(outBuffer, outSize);
zstream.next_out := PAnsiChar(Integer(outBuffer) + zstream.total_out);
zstream.avail_out := delta;
end;
finally
ZCompressCheck(deflateEnd(zstream));
end;
ReallocMem(outBuffer, zstream.total_out);
outSize := zstream.total_out;
except
FreeMem(outBuffer);
raise;
end;
end;
procedure ZCompress(const inBuffer: Pointer; inSize: Integer;
out outBuffer: Pointer; out outSize: Integer;
level: TCompressionLevel);
begin
ZCompress(inBuffer, inSize, outBuffer, outSize, TZCompressionLevel(Integer(level)));
end;
procedure ZCompress2(const inBuffer: Pointer; inSize: Integer;
out outBuffer: Pointer; out outSize: Integer);
const
delta = 256;
var
zstream: TZStreamRec;
begin
FillChar(zstream, SizeOf(TZStreamRec), 0);
outSize := ((inSize + (inSize div 10) + 12) + 255) and not 255;
GetMem(outBuffer, outSize);
try
zstream.next_in := inBuffer;
zstream.avail_in := inSize;
zstream.next_out := outBuffer;
zstream.avail_out := outSize;
ZCompressCheck(DeflateInit2(zstream, 1, 8, -15, 9, 0));
try
while ZCompressCheck(deflate(zstream, Z_FINISH)) <> Z_STREAM_END do
begin
Inc(outSize, delta);
ReallocMem(outBuffer, outSize);
zstream.next_out := PAnsiChar(Integer(outBuffer) + zstream.total_out);
zstream.avail_out := delta;
end;
finally
ZCompressCheck(deflateEnd(zstream));
end;
ReallocMem(outBuffer, zstream.total_out);
outSize := zstream.total_out;
except
FreeMem(outBuffer);
raise;
end;
end;
procedure ZDecompress(const inBuffer: Pointer; inSize: Integer;
out outBuffer: Pointer; out outSize: Integer; outEstimate: Integer);
var
zstream: TZStreamRec;
delta: Integer;
begin
FillChar(zstream, SizeOf(TZStreamRec), 0);
delta := (inSize + 255) and not 255;
if outEstimate = 0 then outSize := delta
else outSize := outEstimate;
GetMem(outBuffer, outSize);
try
zstream.next_in := inBuffer;
zstream.avail_in := inSize;
zstream.next_out := outBuffer;
zstream.avail_out := outSize;
ZDecompressCheck(InflateInit(zstream));
try
while ZDecompressCheck(inflate(zstream, Z_NO_FLUSH)) <> Z_STREAM_END do
begin
Inc(outSize, delta);
ReallocMem(outBuffer, outSize);
zstream.next_out := PAnsiChar(Integer(outBuffer) + zstream.total_out);
zstream.avail_out := delta;
end;
finally
ZDecompressCheck(inflateEnd(zstream));
end;
ReallocMem(outBuffer, zstream.total_out);
outSize := zstream.total_out;
except
FreeMem(outBuffer);
raise;
end;
end;
{** string routines *********************************************************}
function ZCompressStr(const s: string; level: TZCompressionLevel): TBytes;
var
buffer: Pointer;
size: Integer;
begin
ZCompress(PChar(s), Length(s) * SizeOf(Char), buffer, size, level);
SetLength(result, size);
Move(buffer^, pointer(result)^, size);
FreeMem(buffer);
end;
function ZCompressStr(const s: string; level: TCompressionLevel): TBytes;
begin
Result := ZCompressStr(s, TZCompressionLevel(Integer(level)));
end;
{$IF NOT DECLARED(ByteLength)}
function ByteLength(const S: string): Integer;
begin
Result := Length(S) * SizeOf(Char);
end;
{$IFEND}
procedure ZSendToBrowser(var s: string);
var
outBuf: Pointer;
outBytes: Integer;
begin
ZCompress2(pointer(s), ByteLength(s), outBuf, outBytes);
SetLength(s, outBytes);
Move(pointer(outBuf)^, pointer(s)^, outBytes);
FreeMem(outBuf);
end;
function ZDecompressStr(const s: TBytes): string;
var
buffer: Pointer;
size: Integer;
begin
ZDecompress(Pointer(s), Length(s), buffer, size);
SetLength(result, size div SizeOf(Char));
Move(buffer^, pointer(result)^, size);
FreeMem(buffer);
end;
{** stream routines *********************************************************}
procedure ZCompressStream(inStream, outStream: TStream;
level: TZCompressionLevel);
const
bufferSize = 32768;
var
zstream: TZStreamRec;
zresult: Integer;
inBuffer: array[0..bufferSize - 1] of AnsiChar;
outBuffer: array[0..bufferSize - 1] of AnsiChar;
inSize: Integer;
outSize: Integer;
begin
FillChar(zstream, SizeOf(TZStreamRec), 0);
ZCompressCheck(DeflateInit(zstream, ZLevels[level]));
inSize := inStream.Read(inBuffer, bufferSize);
while inSize > 0 do
begin
zstream.next_in := inBuffer;
zstream.avail_in := inSize;
repeat
zstream.next_out := outBuffer;
zstream.avail_out := bufferSize;
ZCompressCheck(deflate(zstream, Z_NO_FLUSH));
// outSize := zstream.next_out - outBuffer;
outSize := bufferSize - zstream.avail_out;
outStream.Write(outBuffer, outSize);
until (zstream.avail_in = 0) and (zstream.avail_out > 0);
inSize := inStream.Read(inBuffer, bufferSize);
end;
repeat
zstream.next_out := outBuffer;
zstream.avail_out := bufferSize;
zresult := ZCompressCheck(deflate(zstream, Z_FINISH));
// outSize := zstream.next_out - outBuffer;
outSize := bufferSize - zstream.avail_out;
outStream.Write(outBuffer, outSize);
until (zresult = Z_STREAM_END) and (zstream.avail_out > 0);
ZCompressCheck(deflateEnd(zstream));
end;
procedure ZCompressStream(inStream, outStream: TStream;
level: TCompressionLevel);
begin
ZCompressStream(inStream, outStream, TZCompressionLevel(Integer(level)))
end;
procedure ZDecompressStream(inStream, outStream: TStream);
const
bufferSize = 32768;
var
zstream: TZStreamRec;
zresult: Integer;
inBuffer: array[0..bufferSize - 1] of AnsiChar;
outBuffer: array[0..bufferSize - 1] of AnsiChar;
inSize: Integer;
outSize: Integer;
begin
FillChar(zstream, SizeOf(TZStreamRec), 0);
ZCompressCheck(InflateInit(zstream));
inSize := inStream.Read(inBuffer, bufferSize);
while inSize > 0 do
begin
zstream.next_in := inBuffer;
zstream.avail_in := inSize;
repeat
zstream.next_out := outBuffer;
zstream.avail_out := bufferSize;
ZCompressCheck(inflate(zstream, Z_NO_FLUSH));
// outSize := zstream.next_out - outBuffer;
outSize := bufferSize - zstream.avail_out;
outStream.Write(outBuffer, outSize);
until (zstream.avail_in = 0) and (zstream.avail_out > 0);
inSize := inStream.Read(inBuffer, bufferSize);
end;
repeat
zstream.next_out := outBuffer;
zstream.avail_out := bufferSize;
zresult := ZCompressCheck(inflate(zstream, Z_FINISH));
// outSize := zstream.next_out - outBuffer;
outSize := bufferSize - zstream.avail_out;
outStream.Write(outBuffer, outSize);
until (zresult = Z_STREAM_END) and (zstream.avail_out > 0);
ZCompressCheck(inflateEnd(zstream));
end;
{** TCustomZStream **********************************************************}
constructor TCustomZStream.Create(stream: TStream);
begin
inherited Create;
FStream := stream;
FStreamPos := stream.Position;
end;
procedure TCustomZStream.DoProgress;
begin
if Assigned(FOnProgress) then FOnProgress(Self);
end;
{** TZCompressionStream *****************************************************}
constructor TZCompressionStream.Create(dest: TStream;
compressionLevel: TZCompressionLevel);
begin
inherited Create(dest);
FZStream.next_out := FBuffer;
FZStream.avail_out := SizeOf(FBuffer);
ZCompressCheck(DeflateInit(FZStream, ZLevels[compressionLevel]));
end;
constructor TZCompressionStream.Create(compressionLevel: TCompressionLevel; dest: TStream);
begin
Create(dest, TZCompressionLevel(Byte(compressionLevel)));
end;
destructor TZCompressionStream.Destroy;
begin
FZStream.next_in := nil;
FZStream.avail_in := 0;
try
if FStream.Position <> FStreamPos then FStream.Position := FStreamPos;
while ZCompressCheck(deflate(FZStream, Z_FINISH)) <> Z_STREAM_END do
begin
FStream.WriteBuffer(FBuffer, SizeOf(FBuffer) - FZStream.avail_out);
FZStream.next_out := FBuffer;
FZStream.avail_out := SizeOf(FBuffer);
end;
if FZStream.avail_out < SizeOf(FBuffer) then
begin
FStream.WriteBuffer(FBuffer, SizeOf(FBuffer) - FZStream.avail_out);
end;
finally
deflateEnd(FZStream);
end;
inherited Destroy;
end;
function TZCompressionStream.Read(var buffer; count: Longint): Longint;
begin
raise EZCompressionError.Create(SZInvalid);
end;
function TZCompressionStream.Write(const buffer; count: Longint): Longint;
begin
FZStream.next_in := @buffer;
FZStream.avail_in := count;
if FStream.Position <> FStreamPos then FStream.Position := FStreamPos;
while FZStream.avail_in > 0 do
begin
ZCompressCheck(deflate(FZStream, Z_NO_FLUSH));
if FZStream.avail_out = 0 then
begin
FStream.WriteBuffer(FBuffer, SizeOf(FBuffer));
FZStream.next_out := FBuffer;
FZStream.avail_out := SizeOf(FBuffer);
FStreamPos := FStream.Position;
DoProgress;
end;
end;
result := Count;
end;
function TZCompressionStream.Seek(offset: Longint; origin: Word): Longint;
begin
if (offset = 0) and (origin = soFromCurrent) then
begin
result := FZStream.total_in;
end
else raise EZCompressionError.Create(SZInvalid);
end;
function TZCompressionStream.GetCompressionRate: Single;
begin
if FZStream.total_in = 0 then result := 0
else result := (1.0 - (FZStream.total_out / FZStream.total_in)) * 100.0;
end;
{** TZDecompressionStream ***************************************************}
constructor TZDecompressionStream.Create(source: TStream);
begin
inherited Create(source);
FZStream.next_in := FBuffer;
FZStream.avail_in := 0;
ZDecompressCheck(InflateInit(FZStream));
end;
destructor TZDecompressionStream.Destroy;
begin
inflateEnd(FZStream);
inherited Destroy;
end;
function TZDecompressionStream.Read(var buffer; count: Longint): Longint;
var
zresult: Integer;
begin
FZStream.next_out := @buffer;
FZStream.avail_out := count;
if FStream.Position <> FStreamPos then FStream.Position := FStreamPos;
zresult := Z_OK;
while (FZStream.avail_out > 0) and (zresult <> Z_STREAM_END) do
begin
if FZStream.avail_in = 0 then
begin
FZStream.avail_in := FStream.Read(FBuffer, SizeOf(FBuffer));
if FZStream.avail_in = 0 then
begin
result := count - FZStream.avail_out;
Exit;
end;
FZStream.next_in := FBuffer;
FStreamPos := FStream.Position;
DoProgress;
end;
zresult := ZDecompressCheck(inflate(FZStream, Z_NO_FLUSH));
end;
if (zresult = Z_STREAM_END) and (FZStream.avail_in > 0) then
begin
FStream.Position := FStream.Position - FZStream.avail_in;
FStreamPos := FStream.Position;
FZStream.avail_in := 0;
end;
result := count - FZStream.avail_out;
end;
function TZDecompressionStream.Write(const Buffer; Count: Longint): Longint;
begin
raise EZDecompressionError.Create(SZInvalid);
end;
function TZDecompressionStream.Seek(Offset: Longint; Origin: Word): Longint;
var
buf: array[0..8191] of Char;
i: Integer;
begin
if (offset = 0) and (origin = soFromBeginning) then
begin
ZDecompressCheck(inflateReset(FZStream));
FZStream.next_in := FBuffer;
FZStream.avail_in := 0;
FStream.Position := 0;
FStreamPos := 0;
end
else if ((offset >= 0) and (origin = soFromCurrent)) or
(((offset - FZStream.total_out) > 0) and (origin = soFromBeginning)) then
begin
if origin = soFromBeginning then Dec(offset, FZStream.total_out);
if offset > 0 then
begin
for i := 1 to offset div SizeOf(buf) do ReadBuffer(buf, SizeOf(buf));
ReadBuffer(buf, offset mod SizeOf(buf));
end;
end
else if (offset = 0) and (origin = soFromEnd) then
begin
while Read(buf, SizeOf(buf)) > 0 do ;
end
else raise EZDecompressionError.Create(SZInvalid);
result := FZStream.total_out;
end;
function zlibAllocMem(AppData: Pointer; Items, Size: Integer): Pointer;
{$IFDEF MSWINDOWS}
register;
{$ENDIF}
{$IFDEF LINUX}
cdecl;
{$ENDIF}
begin
Result := AllocMem(Items * Size);
end;
procedure zlibFreeMem(AppData, Block: Pointer);
{$IFDEF MSWINDOWS}
register;
{$ENDIF}
{$IFDEF LINUX}
cdecl;
{$ENDIF}
begin
FreeMem(Block);
end;
end.