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 function  e_Buffer_Read_Int64(B: pTBuffer): Int64;
  54
  55 function  e_Buffer_Read_String(B: pTBuffer): string;
  56
  57 function  e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
  58
  59
  60 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
  61
  62 function  e_Raw_Read_Char(P: Pointer): Char;
  63
  64 function  e_Raw_Read_Byte(P: Pointer): Byte;
  65 function  e_Raw_Read_Word(P: Pointer): Word;
  66 function  e_Raw_Read_LongWord(P: Pointer): LongWord;
  67
  68 function  e_Raw_Read_ShortInt(P: Pointer): ShortInt;
  69 function  e_Raw_Read_SmallInt(P: Pointer): SmallInt;
  70 function  e_Raw_Read_LongInt(P: Pointer): LongInt;
  71
  72 function  e_Raw_Read_String(P: Pointer): string;
  73
  74 function  e_Raw_Read_MD5(P: Pointer): TMD5Digest;
  75
  76 procedure e_Raw_Seek(I: Cardinal);
  77
  78 implementation
  79
  80 uses SysUtils, BinEditor;
  81
  82 procedure e_Buffer_Clear(B: pTBuffer);
  83 begin
  84   B^.WritePos := 0;
  85   B^.ReadPos := 0;
  86   B^.Len := 0;
  87 end;
  88
  89
  90 procedure e_Buffer_Write_Generic(B: pTBuffer; var V; N: Cardinal);
  91 begin
  92   if (B^.WritePos + N >= BUF_SIZE) then Exit;
  93   if (B^.WritePos + N > B^.Len) then
  94     B^.Len := B^.WritePos + N + 1;
  95
  96   CopyMemory(Pointer(Cardinal(Addr(B^.Data)) + B^.WritePos),
  97              @V, N);
  98
  99   B^.WritePos := B^.WritePos + N;
 100 end;
 101 procedure e_Buffer_Read_Generic(B: pTBuffer; var V; N: Cardinal);
 102 begin
 103   if (B^.ReadPos + N >= BUF_SIZE) then Exit;
 104
 105   CopyMemory(@V, Pointer(Cardinal(Addr(B^.Data)) + B^.ReadPos), N);
 106
 107   B^.ReadPos := B^.ReadPos + N;
 108 end;
 109
 110
 111 procedure e_Buffer_Write(B: pTBuffer; V: Char); overload;
 112 begin
 113   e_Buffer_Write_Generic(B, V, 1);
 114 end;
 115
 116 procedure e_Buffer_Write(B: pTBuffer; V: Byte); overload;
 117 begin
 118   e_Buffer_Write_Generic(B, V, 1);
 119 end;
 120 procedure e_Buffer_Write(B: pTBuffer; V: Word); overload;
 121 begin
 122   e_Buffer_Write_Generic(B, V, 2);
 123 end;
 124 procedure e_Buffer_Write(B: pTBuffer; V: LongWord); overload;
 125 begin
 126   e_Buffer_Write_Generic(B, V, 4);
 127 end;
 128
 129 procedure e_Buffer_Write(B: pTBuffer; V: ShortInt); overload;
 130 begin
 131   e_Buffer_Write_Generic(B, V, 1);
 132 end;
 133 procedure e_Buffer_Write(B: pTBuffer; V: SmallInt); overload;
 134 begin
 135   e_Buffer_Write_Generic(B, V, 2);
 136 end;
 137 procedure e_Buffer_Write(B: pTBuffer; V: LongInt); overload;
 138 begin
 139   e_Buffer_Write_Generic(B, V, 4);
 140 end;
 141
 142 procedure e_Buffer_Write(B: pTBuffer; V: string); overload;
 143 var
 144   Len: Byte;
 145   P: Cardinal;
 146 begin
 147   Len := Length(V);
 148   e_Buffer_Write_Generic(B, Len, 1);
 149
 150   if (Len = 0) then Exit;
 151
 152   P := B^.WritePos + Len;
 153   if (P >= BUF_SIZE) then
 154   begin
 155     Len := BUF_SIZE - B^.WritePos;
 156     P := BUF_SIZE;
 157   end;
 158
 159   if (P > B^.Len) then B^.Len := P;
 160
 161   CopyMemory(Pointer(Cardinal(Addr(B^.Data)) + B^.WritePos),
 162              @V[1], Len);
 163
 164   B^.WritePos := P;
 165 end;
 166
 167 procedure e_Buffer_Write(B: pTBuffer; V: TMD5Digest); overload;
 168 var
 169   I: Integer;
 170 begin
 171   for I := 0 to 15 do
 172     e_Buffer_Write(B, V[I]);
 173 end;
 174
 175
 176 function e_Buffer_Read_Char(B: pTBuffer): Char;
 177 begin
 178   e_Buffer_Read_Generic(B, Result, 1);
 179 end;
 180
 181 function e_Buffer_Read_Byte(B: pTBuffer): Byte;
 182 begin
 183   e_Buffer_Read_Generic(B, Result, 1);
 184 end;
 185 function e_Buffer_Read_Word(B: pTBuffer): Word;
 186 begin
 187   e_Buffer_Read_Generic(B, Result, 2);
 188 end;
 189 function e_Buffer_Read_LongWord(B: pTBuffer): LongWord;
 190 begin
 191   e_Buffer_Read_Generic(B, Result, 4);
 192 end;
 193
 194 function e_Buffer_Read_ShortInt(B: pTBuffer): ShortInt;
 195 begin
 196   e_Buffer_Read_Generic(B, Result, 1);
 197 end;
 198 function e_Buffer_Read_SmallInt(B: pTBuffer): SmallInt;
 199 begin
 200   e_Buffer_Read_Generic(B, Result, 2);
 201 end;
 202 function e_Buffer_Read_LongInt(B: pTBuffer): LongInt;
 203 begin
 204   e_Buffer_Read_Generic(B, Result, 4);
 205 end;
 206 function e_Buffer_Read_Int64(B: pTBuffer): Int64;
 207 begin
 208   e_Buffer_Read_Generic(B, Result, 8);
 209 end;
 210
 211 function e_Buffer_Read_String(B: pTBuffer): string;
 212 var
 213   Len: Byte;
 214 begin
 215   Len := e_Buffer_Read_Byte(B);
 216   Result := '';
 217   if Len = 0 then Exit;
 218
 219   if B^.ReadPos + Len > B^.Len then
 220     Len := B^.Len - B^.ReadPos;
 221
 222   SetLength(Result, Len);
 223   CopyMemory(@Result[1], Pointer(Cardinal(Addr(B^.Data)) + B^.ReadPos), Len);
 224
 225   B^.ReadPos := B^.ReadPos + Len;
 226 end;
 227
 228 function e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
 229 var
 230   I: Integer;
 231 begin
 232   for I := 0 to 15 do
 233     Result[I] := e_Buffer_Read_Byte(B);
 234 end;
 235
 236 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
 237 begin
 238   CopyMemory(@V, Pointer(Cardinal(P) + RawPos), N);
 239
 240   RawPos := RawPos + N;
 241 end;
 242
 243 function e_Raw_Read_Char(P: Pointer): Char;
 244 begin
 245   e_Raw_Read_Generic(P, Result, 1);
 246 end;
 247
 248 function e_Raw_Read_Byte(P: Pointer): Byte;
 249 begin
 250   e_Raw_Read_Generic(P, Result, 1);
 251 end;
 252 function e_Raw_Read_Word(P: Pointer): Word;
 253 begin
 254   e_Raw_Read_Generic(P, Result, 2);
 255 end;
 256 function e_Raw_Read_LongWord(P: Pointer): LongWord;
 257 begin
 258   e_Raw_Read_Generic(P, Result, 4);
 259 end;
 260
 261 function e_Raw_Read_ShortInt(P: Pointer): ShortInt;
 262 begin
 263   e_Raw_Read_Generic(P, Result, 1);
 264 end;
 265 function e_Raw_Read_SmallInt(P: Pointer): SmallInt;
 266 begin
 267   e_Raw_Read_Generic(P, Result, 2);
 268 end;
 269 function e_Raw_Read_LongInt(P: Pointer): LongInt;
 270 begin
 271   e_Raw_Read_Generic(P, Result, 4);
 272 end;
 273
 274 function e_Raw_Read_String(P: Pointer): string;
 275 var
 276   Len: Byte;
 277 begin
 278   Len := e_Raw_Read_Byte(P);
 279   Result := '';
 280   if Len = 0 then Exit;
 281
 282   SetLength(Result, Len);
 283   CopyMemory(@Result[1], Pointer(Cardinal(P) + RawPos), Len);
 284
 285   RawPos := RawPos + Len;
 286 end;
 287
 288 function e_Raw_Read_MD5(P: Pointer): TMD5Digest;
 289 var
 290   I: Integer;
 291 begin
 292   for I := 0 to 15 do
 293     Result[I] := e_Raw_Read_Byte(P);
 294 end;
 295
 296 procedure e_Raw_Seek(I: Cardinal);
 297 begin
 298   RawPos := I;
 299 end;
 300
 301 end.