untaPlib by ErazerZ

{

  untaPlib by ErazerZ

  25. Juni 2006

  Example:

    CompressFile('c:\Data.dat', 'c:\Compressed.dat');

    DecompressFile('c:\Compressed.dat', 'c:\Data_ok.dat');

}

unit untaPlib;

interface

uses Windows;

function CompressMemory(lpBuffer: Pointer; var Size: Cardinal): Pointer;

function DecompressMemory(lpBuffer: Pointer; var Size: Cardinal): Pointer;

function CompressFile(lpFilename, lpOutputfile: String): Boolean;

function DecompressFile(lpFilename, lpOutputfile: String): Boolean;

{

  Taken out from aPlibu

}

type

  TaPack_Status = function(w0, w1, w2 : DWORD; cbparam : Pointer) : DWORD;cdecl;

  function _aP_pack(var Source; var Destination; Length : DWORD; var WorkMem; Callback: TaPack_Status; cbparam : Pointer): DWORD; cdecl;

  function _aP_workmem_size(InputSize : DWORD): DWORD; cdecl;

  function _aPsafe_pack(var Source; var Destination; Length : DWORD; var WorkMem; Callback : TaPack_Status; cbparam : Pointer): DWORD; cdecl;

  function _aPsafe_get_orig_size(var Source): DWORD; cdecl;

  function _aPsafe_depack(var Source; SrcLen: DWORD; var Destination; DstLen :DWORD): DWORD; cdecl;

  function _aP_depack_asm(var Source, Destination) : DWORD; cdecl;

  function _aP_crc32(var Source; Length : DWORD): DWORD; cdecl;

  function _aP_depack_asm_safe(var Source; SrcLen : DWORD; var Destination; DstLen :DWORD) : DWORD; cdecl;

implementation

function _aP_pack(var Source; var Destination; Length : DWORD; var WorkMem; Callback : TaPack_Status; cbparam : Pointer) : DWORD; external;

function _aP_workmem_size(InputSize : DWORD) : DWORD; external;

function _aPsafe_pack(var Source; var Destination; Length : DWORD; var WorkMem; Callback : TaPack_Status; cbparam : Pointer) : DWORD; external;

function _aPsafe_get_orig_size(var Source) : DWORD; external;

function _aPsafe_depack(var Source; SrcLen : DWORD; var Destination; DstLen :DWORD) : DWORD; external;

function _aP_depack_asm(var Source, Destination) : DWORD; external;

function _aP_crc32(var Source; Length : DWORD): DWORD; external;

function _aP_depack_asm_safe(var Source; SrcLen : DWORD; var Destination; DstLen :DWORD) : DWORD; external;

function GetPointerSize(lpBuffer: Pointer): Cardinal;

begin

  if lpBuffer = nil then

    Result := Cardinal(-1)

  else

    Result := Cardinal(Pointer(Cardinal(lpBuffer) -4)^) and $7FFFFFFC -4;

end;

{

  Result: Pointer of the Compressed Buffer.

  lpBuffer: Buffer that should be compressed.

  var Size: Length of how much should be compressed, later the compressed size.

  Safe: Should be True

}

function CompressMemory(lpBuffer: Pointer; var Size: Cardinal): Pointer;

var

  lpOutput, lpWorkspace: Pointer;

begin

  Result := nil;

  if lpBuffer = nil then

    Exit;

  if Size = INVALID_HANDLE_VALUE then

    Size := GetPointerSize(lpBuffer);

  lpWorkspace := VirtualAlloc(nil, _aP_workmem_size(Size), MEM_COMMIT, PAGE_READWRITE);

  lpOutput := VirtualAlloc(nil, Size, MEM_COMMIT, PAGE_READWRITE);

  Size := _aPsafe_pack(lpBuffer^, lpOutput^, Size, lpWorkspace^, nil, nil);

  Result := lpOutput;

  VirtualFree(lpWorkspace, 0, MEM_RELEASE);

end;

{

  Result: Pointer of the Decompressed Buffer.

  lpBuffer: Buffer that should be decompressed.

  var Size: Length of how much should be decompressed (FileSize), later the decompressed size.

  Safe: Should be True

}

function DecompressMemory(lpBuffer: Pointer; var Size: Cardinal): Pointer;

var

  lpOutput: Pointer;

  dwOrginalSize: Cardinal;

begin

  Result := nil;

  if lpBuffer = nil then

    Exit;

  if Size = INVALID_HANDLE_VALUE then

    Size := GetPointerSize(lpBuffer);

  dwOrginalSize := _aPsafe_get_orig_size(lpBuffer^);

  if (dwOrginalSize <> INVALID_HANDLE_VALUE) or (dwOrginalSize <> 0) then

  begin

    lpOutput := VirtualAlloc(nil, dwOrginalSize, MEM_COMMIT, PAGE_READWRITE);

    Size := _aPsafe_depack(lpBuffer^, Size, lpOutput^, dwOrginalSize) ;

    Result := lpOutput;

  end;

end;

function CompressFile(lpFilename, lpOutputfile: String): Boolean;

var

  hFileIn, hFileMappingObjectIn,

  hFileOut: THandle;

  dwFileSize, lpNumberOfBytesWritten: DWORD;

  lpBaseAddressIn, lpBuffer: Pointer;

begin

  Result := False;

  hFileIn := CreateFile(PChar(lpFilename), GENERIC_READ or GENERIC_WRITE, FILE_SHARE_READ or FILE_SHARE_WRITE, nil, OPEN_ALWAYS, 0, 0);

  if hFileIn = INVALID_HANDLE_VALUE then

    Exit;

  dwFileSize := Windows.GetFileSize(hFileIn, nil);

  hFileMappingObjectIn := CreateFileMapping(hFileIn, nil, PAGE_READWRITE, 0, 0, nil);

  lpBaseAddressIn := MapViewOfFile(hFileMappingObjectIn, FILE_MAP_READ or FILE_MAP_WRITE, 0, 0, 0);

  lpBuffer := CompressMemory(lpBaseAddressIn, dwFileSize);

  hFileOut := CreateFile(PChar(lpOutputfile), GENERIC_READ or GENERIC_WRITE, FILE_SHARE_READ or FILE_SHARE_WRITE, nil, CREATE_ALWAYS, 0, 0);

  if hFileOut <> INVALID_HANDLE_VALUE then

  begin

    WriteFile(hFileOut, lpBuffer^, dwFileSize, lpNumberOfBytesWritten, nil);

    CloseHandle(hFileOut);

  end;

  UnmapViewOfFile(lpBaseAddressIn);

  CloseHandle(hFileMappingObjectIn);

  CloseHandle(hFileIn);

end;

function DecompressFile(lpFilename, lpOutputfile: String): Boolean;

var

  hFileIn, hFileMappingObjectIn,

  hFileOut: THandle;

  dwFileSize, lpNumberOfBytesWritten: DWORD;

  lpBaseAddressIn, lpBuffer: Pointer;

begin

  Result := False;

  hFileIn := CreateFile(PChar(lpFilename), GENERIC_READ or GENERIC_WRITE, FILE_SHARE_READ or FILE_SHARE_WRITE, nil, OPEN_ALWAYS, 0, 0);

  if hFileIn = INVALID_HANDLE_VALUE then

    Exit;

  dwFileSize := Windows.GetFileSize(hFileIn, nil);

  hFileMappingObjectIn := CreateFileMapping(hFileIn, nil, PAGE_READWRITE, 0, 0, nil);

  lpBaseAddressIn := MapViewOfFile(hFileMappingObjectIn, FILE_MAP_READ or FILE_MAP_WRITE, 0, 0, 0);

  lpBuffer := DecompressMemory(lpBaseAddressIn, dwFileSize);

  hFileOut := CreateFile(PChar(lpOutputfile), GENERIC_READ or GENERIC_WRITE, FILE_SHARE_READ or FILE_SHARE_WRITE, nil, CREATE_ALWAYS, 0, 0);

  if hFileOut <> INVALID_HANDLE_VALUE then

  begin

    WriteFile(hFileOut, lpBuffer^, dwFileSize, lpNumberOfBytesWritten, nil);

    CloseHandle(hFileOut);

  end;

  VirtualFree(lpBuffer, 0, MEM_RELEASE);

  UnmapViewOfFile(lpBaseAddressIn);

  CloseHandle(hFileMappingObjectIn);

  CloseHandle(hFileIn);

end;

end.