src/engine/e_fixedbuffer.pas

   1 unit e_fixedbuffer;
   2
   3 // ß íå õî÷ó òðàõàòüñÿ ñ êëàññàìè è ñîçäàíèåì ïî äâà îáúåêòà íà êàæäûé áóôåð,
   4 // êàê â BinEditor/WADEDITOR, ïîýòîìó áóäåò òàê. Ïëþñ ôèêñèðîâàííûé ðàçìåð
   5 // áûñòðåå.   --   Primus
   6
   7 interface
   8
   9 uses md5asm;
  10
  11 const
  12   BUF_SIZE = 65536;
  13
  14 type
  15   TBuffer = record
  16     Data: array [0..BUF_SIZE] of Byte; // îäèí áàéò ñâåðõó íà âñÿêèé ñëó÷àé
  17     ReadPos: Cardinal;
  18     WritePos: Cardinal;
  19     Len: Cardinal;
  20   end;
  21   pTBuffer = ^TBuffer;
  22
  23 var
  24   RawPos: Cardinal = 0;
  25
  26 procedure e_Buffer_Clear(B: pTBuffer);
  27
  28
  29 procedure e_Buffer_Write_Generic(B: pTBuffer; var V; N: Cardinal);
  30 procedure e_Buffer_Read_Generic(B: pTBuffer; var V; N: Cardinal);
  31
  32
  33 procedure e_Buffer_Write(B: pTBuffer; V: Char); overload;
  34
  35 procedure e_Buffer_Write(B: pTBuffer; V: Byte); overload;
  36 procedure e_Buffer_Write(B: pTBuffer; V: Word); overload;
  37 procedure e_Buffer_Write(B: pTBuffer; V: LongWord); overload;
  38
  39 procedure e_Buffer_Write(B: pTBuffer; V: ShortInt); overload;
  40 procedure e_Buffer_Write(B: pTBuffer; V: SmallInt); overload;
  41 procedure e_Buffer_Write(B: pTBuffer; V: LongInt); overload;
  42
  43 procedure e_Buffer_Write(B: pTBuffer; V: string); overload;
  44
  45 procedure e_Buffer_Write(B: pTBuffer; V: TMD5Digest); overload;
  46
  47
  48 function  e_Buffer_Read_Char(B: pTBuffer): Char;
  49
  50 function  e_Buffer_Read_Byte(B: pTBuffer): Byte;
  51 function  e_Buffer_Read_Word(B: pTBuffer): Word;
  52 function  e_Buffer_Read_LongWord(B: pTBuffer): LongWord;
  53
  54 function  e_Buffer_Read_ShortInt(B: pTBuffer): ShortInt;
  55 function  e_Buffer_Read_SmallInt(B: pTBuffer): SmallInt;
  56 function  e_Buffer_Read_LongInt(B: pTBuffer): LongInt;
  57
  58 function  e_Buffer_Read_String(B: pTBuffer): string;
  59
  60 function  e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
  61
  62
  63 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
  64
  65 function  e_Raw_Read_Char(P: Pointer): Char;
  66
  67 function  e_Raw_Read_Byte(P: Pointer): Byte;
  68 function  e_Raw_Read_Word(P: Pointer): Word;
  69 function  e_Raw_Read_LongWord(P: Pointer): LongWord;
  70
  71 function  e_Raw_Read_ShortInt(P: Pointer): ShortInt;
  72 function  e_Raw_Read_SmallInt(P: Pointer): SmallInt;
  73 function  e_Raw_Read_LongInt(P: Pointer): LongInt;
  74
  75 function  e_Raw_Read_String(P: Pointer): string;
  76
  77 function  e_Raw_Read_MD5(P: Pointer): TMD5Digest;
  78
  79 procedure e_Raw_Seek(I: Cardinal);
  80
  81 implementation
  82
  83 uses Windows, SysUtils;
  84
  85 procedure e_Buffer_Clear(B: pTBuffer);
  86 begin
  87   B^.WritePos := 0;
  88   B^.ReadPos := 0;
  89   B^.Len := 0;
  90 end;
  91
  92
  93 procedure e_Buffer_Write_Generic(B: pTBuffer; var V; N: Cardinal);
  94 begin
  95   if (B^.WritePos + N >= BUF_SIZE) then Exit;
  96   if (B^.WritePos + N > B^.Len) then
  97     B^.Len := B^.WritePos + N + 1;
  98
  99   MoveMemory(Pointer(Cardinal(Addr(B^.Data)) + B^.WritePos),
 100              @V, N);
 101
 102   B^.WritePos := B^.WritePos + N;
 103 end;
 104 procedure e_Buffer_Read_Generic(B: pTBuffer; var V; N: Cardinal);
 105 begin
 106   if (B^.ReadPos + N >= BUF_SIZE) then Exit;
 107
 108   MoveMemory(@V, Pointer(Cardinal(Addr(B^.Data)) + B^.ReadPos), N);
 109
 110   B^.ReadPos := B^.ReadPos + N;
 111 end;
 112
 113
 114 procedure e_Buffer_Write(B: pTBuffer; V: Char); overload;
 115 begin
 116   e_Buffer_Write_Generic(B, V, 1);
 117 end;
 118
 119 procedure e_Buffer_Write(B: pTBuffer; V: Byte); overload;
 120 begin
 121   e_Buffer_Write_Generic(B, V, 1);
 122 end;
 123 procedure e_Buffer_Write(B: pTBuffer; V: Word); overload;
 124 begin
 125   e_Buffer_Write_Generic(B, V, 2);
 126 end;
 127 procedure e_Buffer_Write(B: pTBuffer; V: LongWord); overload;
 128 begin
 129   e_Buffer_Write_Generic(B, V, 4);
 130 end;
 131
 132 procedure e_Buffer_Write(B: pTBuffer; V: ShortInt); overload;
 133 begin
 134   e_Buffer_Write_Generic(B, V, 1);
 135 end;
 136 procedure e_Buffer_Write(B: pTBuffer; V: SmallInt); overload;
 137 begin
 138   e_Buffer_Write_Generic(B, V, 2);
 139 end;
 140 procedure e_Buffer_Write(B: pTBuffer; V: LongInt); overload;
 141 begin
 142   e_Buffer_Write_Generic(B, V, 4);
 143 end;
 144
 145 procedure e_Buffer_Write(B: pTBuffer; V: string); overload;
 146 var
 147   Len: Byte;
 148   P: Cardinal;
 149 begin
 150   Len := Length(V);
 151   e_Buffer_Write_Generic(B, Len, 1);
 152
 153   if (Len = 0) then Exit;
 154
 155   P := B^.WritePos + Len;
 156   if (P >= BUF_SIZE) then
 157   begin
 158     Len := BUF_SIZE - B^.WritePos;
 159     P := BUF_SIZE;
 160   end;
 161
 162   if (P > B^.Len) then B^.Len := P;
 163
 164   CopyMemory(Pointer(Cardinal(Addr(B^.Data)) + B^.WritePos),
 165              @V[1], Len);
 166
 167   B^.WritePos := P;
 168 end;
 169
 170 procedure e_Buffer_Write(B: pTBuffer; V: TMD5Digest); overload;
 171 var
 172   I: Integer;
 173 begin
 174   for I := 0 to 15 do
 175     e_Buffer_Write(B, V.v[I]);
 176 end;
 177
 178
 179 function e_Buffer_Read_Char(B: pTBuffer): Char;
 180 begin
 181   e_Buffer_Read_Generic(B, Result, 1);
 182 end;
 183
 184 function e_Buffer_Read_Byte(B: pTBuffer): Byte;
 185 begin
 186   e_Buffer_Read_Generic(B, Result, 1);
 187 end;
 188 function e_Buffer_Read_Word(B: pTBuffer): Word;
 189 begin
 190   e_Buffer_Read_Generic(B, Result, 2);
 191 end;
 192 function e_Buffer_Read_LongWord(B: pTBuffer): LongWord;
 193 begin
 194   e_Buffer_Read_Generic(B, Result, 4);
 195 end;
 196
 197 function e_Buffer_Read_ShortInt(B: pTBuffer): ShortInt;
 198 begin
 199   e_Buffer_Read_Generic(B, Result, 1);
 200 end;
 201 function e_Buffer_Read_SmallInt(B: pTBuffer): SmallInt;
 202 begin
 203   e_Buffer_Read_Generic(B, Result, 2);
 204 end;
 205 function e_Buffer_Read_LongInt(B: pTBuffer): LongInt;
 206 begin
 207   e_Buffer_Read_Generic(B, Result, 4);
 208 end;
 209
 210 function e_Buffer_Read_String(B: pTBuffer): string;
 211 var
 212   Len: Byte;
 213 begin
 214   Len := e_Buffer_Read_Byte(B);
 215   Result := '';
 216   if Len = 0 then Exit;
 217
 218   if B^.ReadPos + Len > B^.Len then
 219     Len := B^.Len - B^.ReadPos;
 220
 221   SetLength(Result, Len);
 222   MoveMemory(@Result[1], Pointer(Cardinal(Addr(B^.Data)) + B^.ReadPos), Len);
 223
 224   B^.ReadPos := B^.ReadPos + Len;
 225 end;
 226
 227 function e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
 228 var
 229   I: Integer;
 230 begin
 231   for I := 0 to 15 do
 232     Result.v[I] := e_Buffer_Read_Byte(B);
 233 end;
 234
 235 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
 236 begin
 237   MoveMemory(@V, Pointer(Cardinal(P) + RawPos), N);
 238
 239   RawPos := RawPos + N;
 240 end;
 241
 242 function e_Raw_Read_Char(P: Pointer): Char;
 243 begin
 244   e_Raw_Read_Generic(P, Result, 1);
 245 end;
 246
 247 function e_Raw_Read_Byte(P: Pointer): Byte;
 248 begin
 249   e_Raw_Read_Generic(P, Result, 1);
 250 end;
 251 function e_Raw_Read_Word(P: Pointer): Word;
 252 begin
 253   e_Raw_Read_Generic(P, Result, 2);
 254 end;
 255 function e_Raw_Read_LongWord(P: Pointer): LongWord;
 256 begin
 257   e_Raw_Read_Generic(P, Result, 4);
 258 end;
 259
 260 function e_Raw_Read_ShortInt(P: Pointer): ShortInt;
 261 begin
 262   e_Raw_Read_Generic(P, Result, 1);
 263 end;
 264 function e_Raw_Read_SmallInt(P: Pointer): SmallInt;
 265 begin
 266   e_Raw_Read_Generic(P, Result, 2);
 267 end;
 268 function e_Raw_Read_LongInt(P: Pointer): LongInt;
 269 begin
 270   e_Raw_Read_Generic(P, Result, 4);
 271 end;
 272
 273 function e_Raw_Read_String(P: Pointer): string;
 274 var
 275   Len: Byte;
 276 begin
 277   Len := e_Raw_Read_Byte(P);
 278   Result := '';
 279   if Len = 0 then Exit;
 280
 281   SetLength(Result, Len);
 282   MoveMemory(@Result[1], Pointer(Cardinal(P) + RawPos), Len);
 283
 284   RawPos := RawPos + Len;
 285 end;
 286
 287 function e_Raw_Read_MD5(P: Pointer): TMD5Digest;
 288 var
 289   I: Integer;
 290 begin
 291   for I := 0 to 15 do
 292     Result.v[I] := e_Raw_Read_Byte(P);
 293 end;
 294
 295 procedure e_Raw_Seek(I: Cardinal);
 296 begin
 297   RawPos := I;
 298 end;
 299
 300 end.