(* zlibpas -- Pascal interface to the zlib data compression library

 *

 * Copyright (C) 2003 Cosmin Truta.

 * Derived from original sources by Bob Dellaca.

 * For conditions of distribution and use, see copyright notice in readme.txt

 *)

unit zlibpas;

interface

const

  ZLIB_VERSION = '1.2.3';

type

  alloc_func = function(opaque: Pointer; items, size: Integer): Pointer;

                 cdecl;

  free_func  = procedure(opaque, address: Pointer);

                 cdecl;

  in_func    = function(opaque: Pointer; var buf: PByte): Integer;

                 cdecl;

  out_func   = function(opaque: Pointer; buf: PByte; size: Integer): Integer;

                 cdecl;

  z_streamp = ^z_stream;

  z_stream = packed record

    next_in: PChar;       (* next input byte *)

    avail_in: Integer;    (* number of bytes available at next_in *)

    total_in: LongInt;    (* total nb of input bytes read so far *)

    next_out: PChar;      (* next output byte should be put there *)

    avail_out: Integer;   (* remaining free space at next_out *)

    total_out: LongInt;   (* total nb of bytes output so far *)

    msg: PChar;           (* last error message, NULL if no error *)

    state: Pointer;       (* not visible by applications *)

    zalloc: alloc_func;   (* used to allocate the internal state *)

    zfree: free_func;     (* 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;

(* constants *)

const

  Z_NO_FLUSH      = 0;

  Z_PARTIAL_FLUSH = 1;

  Z_SYNC_FLUSH    = 2;

  Z_FULL_FLUSH    = 3;

  Z_FINISH        = 4;

  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;

  Z_NO_COMPRESSION       =  0;

  Z_BEST_SPEED           =  1;

  Z_BEST_COMPRESSION     =  9;

  Z_DEFAULT_COMPRESSION  = -1;

  Z_FILTERED            = 1;

  Z_HUFFMAN_ONLY        = 2;

  Z_RLE                 = 3;

  Z_DEFAULT_STRATEGY    = 0;

  Z_BINARY   = 0;

  Z_ASCII    = 1;

  Z_UNKNOWN  = 2;

  Z_DEFLATED = 8;

(* basic functions *)

function zlibVersion: PChar;

function deflateInit(var strm: z_stream; level: Integer): Integer;

function deflate(var strm: z_stream; flush: Integer): Integer;

function deflateEnd(var strm: z_stream): Integer;

function inflateInit(var strm: z_stream): Integer;

function inflate(var strm: z_stream; flush: Integer): Integer;

function inflateEnd(var strm: z_stream): Integer;

(* advanced functions *)

function deflateInit2(var strm: z_stream; level, method, windowBits,

                      memLevel, strategy: Integer): Integer;

function deflateSetDictionary(var strm: z_stream; const dictionary: PChar;

                              dictLength: Integer): Integer;

function deflateCopy(var dest, source: z_stream): Integer;

function deflateReset(var strm: z_stream): Integer;

function deflateParams(var strm: z_stream; level, strategy: Integer): Integer;

function deflateBound(var strm: z_stream; sourceLen: LongInt): LongInt;

function deflatePrime(var strm: z_stream; bits, value: Integer): Integer;

function inflateInit2(var strm: z_stream; windowBits: Integer): Integer;

function inflateSetDictionary(var strm: z_stream; const dictionary: PChar;

                              dictLength: Integer): Integer;

function inflateSync(var strm: z_stream): Integer;

function inflateCopy(var dest, source: z_stream): Integer;

function inflateReset(var strm: z_stream): Integer;

function inflateBackInit(var strm: z_stream;

                         windowBits: Integer; window: PChar): Integer;

function inflateBack(var strm: z_stream; in_fn: in_func; in_desc: Pointer;

                     out_fn: out_func; out_desc: Pointer): Integer;

function inflateBackEnd(var strm: z_stream): Integer;

function zlibCompileFlags: LongInt;

(* utility functions *)

function compress(dest: PChar; var destLen: LongInt;

                  const source: PChar; sourceLen: LongInt): Integer;

function compress2(dest: PChar; var destLen: LongInt;

                  const source: PChar; sourceLen: LongInt;

                  level: Integer): Integer;

function compressBound(sourceLen: LongInt): LongInt;

function uncompress(dest: PChar; var destLen: LongInt;

                    const source: PChar; sourceLen: LongInt): Integer;

(* checksum functions *)

function adler32(adler: LongInt; const buf: PChar; len: Integer): LongInt;

function crc32(crc: LongInt; const buf: PChar; len: Integer): LongInt;

(* various hacks, don't look :) *)

function deflateInit_(var strm: z_stream; level: Integer;

                      const version: PChar; stream_size: Integer): Integer;

function inflateInit_(var strm: z_stream; const version: PChar;

                      stream_size: Integer): Integer;

function deflateInit2_(var strm: z_stream;

                       level, method, windowBits, memLevel, strategy: Integer;

                       const version: PChar; stream_size: Integer): Integer;

function inflateInit2_(var strm: z_stream; windowBits: Integer;

                       const version: PChar; stream_size: Integer): Integer;

function inflateBackInit_(var strm: z_stream;

                          windowBits: Integer; window: PChar;

                          const version: PChar; stream_size: Integer): Integer;

implementation

{$L adler32.obj}

{$L compress.obj}

{$L crc32.obj}

{$L deflate.obj}

{$L infback.obj}

{$L inffast.obj}

{$L inflate.obj}

{$L inftrees.obj}

{$L trees.obj}

{$L uncompr.obj}

{$L zutil.obj}

function adler32; external;

function compress; external;

function compress2; external;

function compressBound; external;

function crc32; external;

function deflate; external;

function deflateBound; external;

function deflateCopy; external;

function deflateEnd; external;

function deflateInit_; external;

function deflateInit2_; external;

function deflateParams; external;

function deflatePrime; external;

function deflateReset; external;

function deflateSetDictionary; external;

function inflate; external;

function inflateBack; external;

function inflateBackEnd; external;

function inflateBackInit_; external;

function inflateCopy; external;

function inflateEnd; external;

function inflateInit_; external;

function inflateInit2_; external;

function inflateReset; external;

function inflateSetDictionary; external;

function inflateSync; external;

function uncompress; external;

function zlibCompileFlags; external;

function zlibVersion; external;

function deflateInit(var strm: z_stream; level: Integer): Integer;

begin

  Result := deflateInit_(strm, level, ZLIB_VERSION, sizeof(z_stream));

end;

function deflateInit2(var strm: z_stream; level, method, windowBits, memLevel,

                      strategy: Integer): Integer;

begin

  Result := deflateInit2_(strm, level, method, windowBits, memLevel, strategy,

                          ZLIB_VERSION, sizeof(z_stream));

end;

function inflateInit(var strm: z_stream): Integer;

begin

  Result := inflateInit_(strm, ZLIB_VERSION, sizeof(z_stream));

end;

function inflateInit2(var strm: z_stream; windowBits: Integer): Integer;

begin

  Result := inflateInit2_(strm, windowBits, ZLIB_VERSION, sizeof(z_stream));

end;

function inflateBackInit(var strm: z_stream;

                         windowBits: Integer; window: PChar): Integer;

begin

  Result := inflateBackInit_(strm, windowBits, window,

                             ZLIB_VERSION, sizeof(z_stream));

end;

function _malloc(Size: Integer): Pointer; cdecl;

begin

  GetMem(Result, Size);

end;

procedure _free(Block: Pointer); cdecl;

begin

  FreeMem(Block);

end;

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;

end.