src/engine/e_fixedbuffer.pas

   1 (* Copyright (C)  DooM 2D:Forever Developers
   2  *
   3  * This program is free software: you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation, either version 3 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  *)
  16 {$INCLUDE e_amodes.inc}
  17 unit e_fixedbuffer;
  18
  19 interface
  20
  21 uses md5;
  22
  23 const
  24   BUF_SIZE = 65536;
  25
  26 type
  27   TBuffer = record
  28     Data: array [0..BUF_SIZE] of Byte; // îäèí áàéò ñâåðõó íà âñÿêèé ñëó÷àé
  29     ReadPos: Cardinal;
  30     WritePos: Cardinal;
  31     Len: Cardinal;
  32   end;
  33   pTBuffer = ^TBuffer;
  34
  35 var
  36   RawPos: Cardinal = 0;
  37
  38 procedure e_Buffer_Clear(B: pTBuffer);
  39
  40
  41 procedure e_Buffer_Write_Generic(B: pTBuffer; var V; N: Cardinal);
  42 procedure e_Buffer_Read_Generic(B: pTBuffer; var V; N: Cardinal);
  43
  44
  45 procedure e_Buffer_Write(B: pTBuffer; V: Char); overload;
  46
  47 procedure e_Buffer_Write(B: pTBuffer; V: Byte); overload;
  48 procedure e_Buffer_Write(B: pTBuffer; V: Word); overload;
  49 procedure e_Buffer_Write(B: pTBuffer; V: LongWord); overload;
  50
  51 procedure e_Buffer_Write(B: pTBuffer; V: ShortInt); overload;
  52 procedure e_Buffer_Write(B: pTBuffer; V: SmallInt); overload;
  53 procedure e_Buffer_Write(B: pTBuffer; V: LongInt); overload;
  54 procedure e_Buffer_Write(B: pTBuffer; V: Int64); overload;
  55
  56 procedure e_Buffer_Write(B: pTBuffer; V: string); overload;
  57
  58 procedure e_Buffer_Write(B: pTBuffer; V: TMD5Digest); overload;
  59
  60
  61 function  e_Buffer_Read_Char(B: pTBuffer): Char;
  62
  63 function  e_Buffer_Read_Byte(B: pTBuffer): Byte;
  64 function  e_Buffer_Read_Word(B: pTBuffer): Word;
  65 function  e_Buffer_Read_LongWord(B: pTBuffer): LongWord;
  66
  67 function  e_Buffer_Read_ShortInt(B: pTBuffer): ShortInt;
  68 function  e_Buffer_Read_SmallInt(B: pTBuffer): SmallInt;
  69 function  e_Buffer_Read_LongInt(B: pTBuffer): LongInt;
  70 function  e_Buffer_Read_Int64(B: pTBuffer): Int64;
  71
  72 function  e_Buffer_Read_String(B: pTBuffer): string;
  73
  74 function  e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
  75
  76
  77 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
  78
  79 function  e_Raw_Read_Char(P: Pointer): Char;
  80
  81 function  e_Raw_Read_Byte(P: Pointer): Byte;
  82 function  e_Raw_Read_Word(P: Pointer): Word;
  83 function  e_Raw_Read_LongWord(P: Pointer): LongWord;
  84
  85 function  e_Raw_Read_ShortInt(P: Pointer): ShortInt;
  86 function  e_Raw_Read_SmallInt(P: Pointer): SmallInt;
  87 function  e_Raw_Read_LongInt(P: Pointer): LongInt;
  88
  89 function  e_Raw_Read_String(P: Pointer): string;
  90
  91 function  e_Raw_Read_MD5(P: Pointer): TMD5Digest;
  92
  93 procedure e_Raw_Seek(I: Cardinal);
  94
  95 implementation
  96
  97 uses SysUtils, BinEditor;
  98
  99 procedure e_Buffer_Clear(B: pTBuffer);
 100 begin
 101   B^.WritePos := 0;
 102   B^.ReadPos := 0;
 103   B^.Len := 0;
 104 end;
 105
 106
 107 procedure e_Buffer_Write_Generic(B: pTBuffer; var V; N: Cardinal);
 108 begin
 109   if (B^.WritePos + N >= BUF_SIZE) then Exit;
 110   if (B^.WritePos + N > B^.Len) then
 111     B^.Len := B^.WritePos + N + 1;
 112
 113   CopyMemory(Pointer(NativeUInt(Addr(B^.Data)) + B^.WritePos),
 114              @V, N);
 115
 116   B^.WritePos := B^.WritePos + N;
 117 end;
 118 procedure e_Buffer_Read_Generic(B: pTBuffer; var V; N: Cardinal);
 119 begin
 120   if (B^.ReadPos + N >= BUF_SIZE) then Exit;
 121
 122   CopyMemory(@V, Pointer(NativeUInt(Addr(B^.Data)) + B^.ReadPos), N);
 123
 124   B^.ReadPos := B^.ReadPos + N;
 125 end;
 126
 127
 128 procedure e_Buffer_Write(B: pTBuffer; V: Char); overload;
 129 begin
 130   e_Buffer_Write_Generic(B, V, 1);
 131 end;
 132
 133 procedure e_Buffer_Write(B: pTBuffer; V: Byte); overload;
 134 begin
 135   e_Buffer_Write_Generic(B, V, 1);
 136 end;
 137 procedure e_Buffer_Write(B: pTBuffer; V: Word); overload;
 138 begin
 139   e_Buffer_Write_Generic(B, V, 2);
 140 end;
 141 procedure e_Buffer_Write(B: pTBuffer; V: LongWord); overload;
 142 begin
 143   e_Buffer_Write_Generic(B, V, 4);
 144 end;
 145
 146 procedure e_Buffer_Write(B: pTBuffer; V: ShortInt); overload;
 147 begin
 148   e_Buffer_Write_Generic(B, V, 1);
 149 end;
 150 procedure e_Buffer_Write(B: pTBuffer; V: SmallInt); overload;
 151 begin
 152   e_Buffer_Write_Generic(B, V, 2);
 153 end;
 154 procedure e_Buffer_Write(B: pTBuffer; V: LongInt); overload;
 155 begin
 156   e_Buffer_Write_Generic(B, V, 4);
 157 end;
 158 procedure e_Buffer_Write(B: pTBuffer; V: Int64); overload;
 159 begin
 160   e_Buffer_Write_Generic(B, V, 8);
 161 end;
 162
 163 procedure e_Buffer_Write(B: pTBuffer; V: string); overload;
 164 var
 165   Len: Byte;
 166   P: Cardinal;
 167 begin
 168   Len := Length(V);
 169   e_Buffer_Write_Generic(B, Len, 1);
 170
 171   if (Len = 0) then Exit;
 172
 173   P := B^.WritePos + Len;
 174   if (P >= BUF_SIZE) then
 175   begin
 176     Len := BUF_SIZE - B^.WritePos;
 177     P := BUF_SIZE;
 178   end;
 179
 180   if (P > B^.Len) then B^.Len := P;
 181
 182   CopyMemory(Pointer(NativeUInt(Addr(B^.Data)) + B^.WritePos),
 183              @V[1], Len);
 184
 185   B^.WritePos := P;
 186 end;
 187
 188 procedure e_Buffer_Write(B: pTBuffer; V: TMD5Digest); overload;
 189 var
 190   I: Integer;
 191 begin
 192   for I := 0 to 15 do
 193     e_Buffer_Write(B, V[I]);
 194 end;
 195
 196
 197 function e_Buffer_Read_Char(B: pTBuffer): Char;
 198 begin
 199   e_Buffer_Read_Generic(B, Result, 1);
 200 end;
 201
 202 function e_Buffer_Read_Byte(B: pTBuffer): Byte;
 203 begin
 204   e_Buffer_Read_Generic(B, Result, 1);
 205 end;
 206 function e_Buffer_Read_Word(B: pTBuffer): Word;
 207 begin
 208   e_Buffer_Read_Generic(B, Result, 2);
 209 end;
 210 function e_Buffer_Read_LongWord(B: pTBuffer): LongWord;
 211 begin
 212   e_Buffer_Read_Generic(B, Result, 4);
 213 end;
 214
 215 function e_Buffer_Read_ShortInt(B: pTBuffer): ShortInt;
 216 begin
 217   e_Buffer_Read_Generic(B, Result, 1);
 218 end;
 219 function e_Buffer_Read_SmallInt(B: pTBuffer): SmallInt;
 220 begin
 221   e_Buffer_Read_Generic(B, Result, 2);
 222 end;
 223 function e_Buffer_Read_LongInt(B: pTBuffer): LongInt;
 224 begin
 225   e_Buffer_Read_Generic(B, Result, 4);
 226 end;
 227 function e_Buffer_Read_Int64(B: pTBuffer): Int64;
 228 begin
 229   e_Buffer_Read_Generic(B, Result, 8);
 230 end;
 231
 232 function e_Buffer_Read_String(B: pTBuffer): string;
 233 var
 234   Len: Byte;
 235 begin
 236   Len := e_Buffer_Read_Byte(B);
 237   Result := '';
 238   if Len = 0 then Exit;
 239
 240   if B^.ReadPos + Len > B^.Len then
 241     Len := B^.Len - B^.ReadPos;
 242
 243   SetLength(Result, Len);
 244   CopyMemory(@Result[1], Pointer(NativeUInt(Addr(B^.Data)) + B^.ReadPos), Len);
 245
 246   B^.ReadPos := B^.ReadPos + Len;
 247 end;
 248
 249 function e_Buffer_Read_MD5(B: pTBuffer): TMD5Digest;
 250 var
 251   I: Integer;
 252 begin
 253   for I := 0 to 15 do
 254     Result[I] := e_Buffer_Read_Byte(B);
 255 end;
 256
 257 procedure e_Raw_Read_Generic(P: Pointer; var V; N: Cardinal);
 258 begin
 259   CopyMemory(@V, Pointer(NativeUInt(P) + RawPos), N);
 260
 261   RawPos := RawPos + N;
 262 end;
 263
 264 function e_Raw_Read_Char(P: Pointer): Char;
 265 begin
 266   e_Raw_Read_Generic(P, Result, 1);
 267 end;
 268
 269 function e_Raw_Read_Byte(P: Pointer): Byte;
 270 begin
 271   e_Raw_Read_Generic(P, Result, 1);
 272 end;
 273 function e_Raw_Read_Word(P: Pointer): Word;
 274 begin
 275   e_Raw_Read_Generic(P, Result, 2);
 276 end;
 277 function e_Raw_Read_LongWord(P: Pointer): LongWord;
 278 begin
 279   e_Raw_Read_Generic(P, Result, 4);
 280 end;
 281
 282 function e_Raw_Read_ShortInt(P: Pointer): ShortInt;
 283 begin
 284   e_Raw_Read_Generic(P, Result, 1);
 285 end;
 286 function e_Raw_Read_SmallInt(P: Pointer): SmallInt;
 287 begin
 288   e_Raw_Read_Generic(P, Result, 2);
 289 end;
 290 function e_Raw_Read_LongInt(P: Pointer): LongInt;
 291 begin
 292   e_Raw_Read_Generic(P, Result, 4);
 293 end;
 294
 295 function e_Raw_Read_String(P: Pointer): string;
 296 var
 297   Len: Byte;
 298 begin
 299   Len := e_Raw_Read_Byte(P);
 300   Result := '';
 301   if Len = 0 then Exit;
 302
 303   SetLength(Result, Len);
 304   CopyMemory(@Result[1], Pointer(NativeUInt(P) + RawPos), Len);
 305
 306   RawPos := RawPos + Len;
 307 end;
 308
 309 function e_Raw_Read_MD5(P: Pointer): TMD5Digest;
 310 var
 311   I: Integer;
 312 begin
 313   for I := 0 to 15 do
 314     Result[I] := e_Raw_Read_Byte(P);
 315 end;
 316
 317 procedure e_Raw_Seek(I: Cardinal);
 318 begin
 319   RawPos := I;
 320 end;
 321
 322 end.