src/engine/e_fixedbuffer.pas

   1 unit e_fixedbuffer;
   2
   3 interface
   4
   5 uses md5;
   6
   7 const
   8   BUF_SIZE = 65536;
   9
  10 type
  11   TBuffer = record
  12     Data: array [0..BUF_SIZE] of Byte; // îäèí áàéò ñâåðõó íà âñÿêèé ñëó÷àé
  13     ReadPos: Cardinal;
  14     WritePos: Cardinal;
  15     Len: Cardinal;
  16   end;
  17   pTBuffer = ^TBuffer;
  18
  19 var
  20   RawPos: Cardinal = 0;
  21
  22 procedure e_Buffer_Clear(B: pTBuffer);
  23
  24
  25 procedure e_Buffer_Write_Generic(B: pTBuffer; var V; N: Cardinal);
  26 procedure e_Buffer_Read_Generic(B: pTBuffer; var V; N: Cardinal);
  27
  28
  29 procedure e_Buffer_Write(B: pTBuffer; V: Char); overload;
  30
  31 procedure e_Buffer_Write(B: pTBuffer; V: Byte); overload;
  32 procedure e_Buffer_Write(B: pTBuffer; V: Word); overload;
  33 procedure e_Buffer_Write(B: pTBuffer; V: LongWord); overload;
  34
  35 procedure e_Buffer_Write(B: pTBuffer; V: ShortInt); overload;
  36 procedure e_Buffer_Write(B: pTBuffer; V: SmallInt); overload;
  37 procedure e_Buffer_Write(B: pTBuffer; V: LongInt); overload;
  38
  39 procedure e_Buffer_Write(B: pTBuffer; V: string); overload;
  40
  41 procedure e_Buffer_Write(B: pTBuffer; V: TMD5Digest); overload;
  42
  43
  44 function  e_Buffer_Read_Char(B: pTBuffer): Char;
  45
  46 function  e_Buffer_Read_Byte(B: pTBuffer): Byte;
  47 function  e_Buffer_Read_Word(B: pTBuffer): Word;
  48 function  e_Buffer_Read_LongWord(B: pTBuffer): LongWord;
  49
  50 function  e_Buffer_Read_ShortInt(B: pTBuffer): ShortInt;
  51 function  e_Buffer_Read_SmallInt(B: pTBuffer): SmallInt;
  52 function  e_Buffer_Read_LongInt(B: pTBuffer): LongInt;
  53
  54 function  e_Buffer_Read_String(B: pTBuffer): string;
  55
  56 function  e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
  57
  58
  59 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
  60
  61 function  e_Raw_Read_Char(P: Pointer): Char;
  62
  63 function  e_Raw_Read_Byte(P: Pointer): Byte;
  64 function  e_Raw_Read_Word(P: Pointer): Word;
  65 function  e_Raw_Read_LongWord(P: Pointer): LongWord;
  66
  67 function  e_Raw_Read_ShortInt(P: Pointer): ShortInt;
  68 function  e_Raw_Read_SmallInt(P: Pointer): SmallInt;
  69 function  e_Raw_Read_LongInt(P: Pointer): LongInt;
  70
  71 function  e_Raw_Read_String(P: Pointer): string;
  72
  73 function  e_Raw_Read_MD5(P: Pointer): TMD5Digest;
  74
  75 procedure e_Raw_Seek(I: Cardinal);
  76
  77 implementation
  78
  79 uses SysUtils, BinEditor;
  80
  81 procedure e_Buffer_Clear(B: pTBuffer);
  82 begin
  83   B^.WritePos := 0;
  84   B^.ReadPos := 0;
  85   B^.Len := 0;
  86 end;
  87
  88
  89 procedure e_Buffer_Write_Generic(B: pTBuffer; var V; N: Cardinal);
  90 begin
  91   if (B^.WritePos + N >= BUF_SIZE) then Exit;
  92   if (B^.WritePos + N > B^.Len) then
  93     B^.Len := B^.WritePos + N + 1;
  94
  95   CopyMemory(Pointer(Cardinal(Addr(B^.Data)) + B^.WritePos),
  96              @V, N);
  97
  98   B^.WritePos := B^.WritePos + N;
  99 end;
 100 procedure e_Buffer_Read_Generic(B: pTBuffer; var V; N: Cardinal);
 101 begin
 102   if (B^.ReadPos + N >= BUF_SIZE) then Exit;
 103
 104   CopyMemory(@V, Pointer(Cardinal(Addr(B^.Data)) + B^.ReadPos), N);
 105
 106   B^.ReadPos := B^.ReadPos + N;
 107 end;
 108
 109
 110 procedure e_Buffer_Write(B: pTBuffer; V: Char); overload;
 111 begin
 112   e_Buffer_Write_Generic(B, V, 1);
 113 end;
 114
 115 procedure e_Buffer_Write(B: pTBuffer; V: Byte); overload;
 116 begin
 117   e_Buffer_Write_Generic(B, V, 1);
 118 end;
 119 procedure e_Buffer_Write(B: pTBuffer; V: Word); overload;
 120 begin
 121   e_Buffer_Write_Generic(B, V, 2);
 122 end;
 123 procedure e_Buffer_Write(B: pTBuffer; V: LongWord); overload;
 124 begin
 125   e_Buffer_Write_Generic(B, V, 4);
 126 end;
 127
 128 procedure e_Buffer_Write(B: pTBuffer; V: ShortInt); overload;
 129 begin
 130   e_Buffer_Write_Generic(B, V, 1);
 131 end;
 132 procedure e_Buffer_Write(B: pTBuffer; V: SmallInt); overload;
 133 begin
 134   e_Buffer_Write_Generic(B, V, 2);
 135 end;
 136 procedure e_Buffer_Write(B: pTBuffer; V: LongInt); overload;
 137 begin
 138   e_Buffer_Write_Generic(B, V, 4);
 139 end;
 140
 141 procedure e_Buffer_Write(B: pTBuffer; V: string); overload;
 142 var
 143   Len: Byte;
 144   P: Cardinal;
 145 begin
 146   Len := Length(V);
 147   e_Buffer_Write_Generic(B, Len, 1);
 148
 149   if (Len = 0) then Exit;
 150
 151   P := B^.WritePos + Len;
 152   if (P >= BUF_SIZE) then
 153   begin
 154     Len := BUF_SIZE - B^.WritePos;
 155     P := BUF_SIZE;
 156   end;
 157
 158   if (P > B^.Len) then B^.Len := P;
 159
 160   CopyMemory(Pointer(Cardinal(Addr(B^.Data)) + B^.WritePos),
 161              @V[1], Len);
 162
 163   B^.WritePos := P;
 164 end;
 165
 166 procedure e_Buffer_Write(B: pTBuffer; V: TMD5Digest); overload;
 167 var
 168   I: Integer;
 169 begin
 170   for I := 0 to 15 do
 171     e_Buffer_Write(B, V[I]);
 172 end;
 173
 174
 175 function e_Buffer_Read_Char(B: pTBuffer): Char;
 176 begin
 177   e_Buffer_Read_Generic(B, Result, 1);
 178 end;
 179
 180 function e_Buffer_Read_Byte(B: pTBuffer): Byte;
 181 begin
 182   e_Buffer_Read_Generic(B, Result, 1);
 183 end;
 184 function e_Buffer_Read_Word(B: pTBuffer): Word;
 185 begin
 186   e_Buffer_Read_Generic(B, Result, 2);
 187 end;
 188 function e_Buffer_Read_LongWord(B: pTBuffer): LongWord;
 189 begin
 190   e_Buffer_Read_Generic(B, Result, 4);
 191 end;
 192
 193 function e_Buffer_Read_ShortInt(B: pTBuffer): ShortInt;
 194 begin
 195   e_Buffer_Read_Generic(B, Result, 1);
 196 end;
 197 function e_Buffer_Read_SmallInt(B: pTBuffer): SmallInt;
 198 begin
 199   e_Buffer_Read_Generic(B, Result, 2);
 200 end;
 201 function e_Buffer_Read_LongInt(B: pTBuffer): LongInt;
 202 begin
 203   e_Buffer_Read_Generic(B, Result, 4);
 204 end;
 205
 206 function e_Buffer_Read_String(B: pTBuffer): string;
 207 var
 208   Len: Byte;
 209 begin
 210   Len := e_Buffer_Read_Byte(B);
 211   Result := '';
 212   if Len = 0 then Exit;
 213
 214   if B^.ReadPos + Len > B^.Len then
 215     Len := B^.Len - B^.ReadPos;
 216
 217   SetLength(Result, Len);
 218   CopyMemory(@Result[1], Pointer(Cardinal(Addr(B^.Data)) + B^.ReadPos), Len);
 219
 220   B^.ReadPos := B^.ReadPos + Len;
 221 end;
 222
 223 function e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
 224 var
 225   I: Integer;
 226 begin
 227   for I := 0 to 15 do
 228     Result[I] := e_Buffer_Read_Byte(B);
 229 end;
 230
 231 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
 232 begin
 233   CopyMemory(@V, Pointer(Cardinal(P) + RawPos), N);
 234
 235   RawPos := RawPos + N;
 236 end;
 237
 238 function e_Raw_Read_Char(P: Pointer): Char;
 239 begin
 240   e_Raw_Read_Generic(P, Result, 1);
 241 end;
 242
 243 function e_Raw_Read_Byte(P: Pointer): Byte;
 244 begin
 245   e_Raw_Read_Generic(P, Result, 1);
 246 end;
 247 function e_Raw_Read_Word(P: Pointer): Word;
 248 begin
 249   e_Raw_Read_Generic(P, Result, 2);
 250 end;
 251 function e_Raw_Read_LongWord(P: Pointer): LongWord;
 252 begin
 253   e_Raw_Read_Generic(P, Result, 4);
 254 end;
 255
 256 function e_Raw_Read_ShortInt(P: Pointer): ShortInt;
 257 begin
 258   e_Raw_Read_Generic(P, Result, 1);
 259 end;
 260 function e_Raw_Read_SmallInt(P: Pointer): SmallInt;
 261 begin
 262   e_Raw_Read_Generic(P, Result, 2);
 263 end;
 264 function e_Raw_Read_LongInt(P: Pointer): LongInt;
 265 begin
 266   e_Raw_Read_Generic(P, Result, 4);
 267 end;
 268
 269 function e_Raw_Read_String(P: Pointer): string;
 270 var
 271   Len: Byte;
 272 begin
 273   Len := e_Raw_Read_Byte(P);
 274   Result := '';
 275   if Len = 0 then Exit;
 276
 277   SetLength(Result, Len);
 278   CopyMemory(@Result[1], Pointer(Cardinal(P) + RawPos), Len);
 279
 280   RawPos := RawPos + Len;
 281 end;
 282
 283 function e_Raw_Read_MD5(P: Pointer): TMD5Digest;
 284 var
 285   I: Integer;
 286 begin
 287   for I := 0 to 15 do
 288     Result[I] := e_Raw_Read_Byte(P);
 289 end;
 290
 291 procedure e_Raw_Seek(I: Cardinal);
 292 begin
 293   RawPos := I;
 294 end;
 295
 296 end.