src/freetype/freetype/internal/ftstream.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  ftstream.h                                                             */
   4 /*                                                                         */
   5 /*    Stream handling(specification).                                      */
   6 /*                                                                         */
   7 /*  Copyright 1996-2000 by                                                 */
   8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
   9 /*                                                                         */
  10 /*  This file is part of the FreeType project, and may only be used,       */
  11 /*  modified, and distributed under the terms of the FreeType project      */
  12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  13 /*  this file you indicate that you have read the license and              */
  14 /*  understand and accept it fully.                                        */
  15 /*                                                                         */
  16 /***************************************************************************/
  17
  18
  19 #ifndef FTSTREAM_H
  20 #define FTSTREAM_H
  21
  22 #include <freetype/internal/ftobjs.h>
  23
  24
  25 #ifdef __cplusplus
  26   extern "C" {
  27 #endif
  28
  29
  30   /* format of an 8-bit frame_op value = [ xxxxx | e | s ] */
  31   /* s is set to 1 if the value is signed,                 */
  32   /* e is set to 1 if the value is little-endian           */
  33   /* xxxxx is a command                                    */
  34
  35 #define FT_FRAME_OP_SHIFT         2
  36 #define FT_FRAME_OP_SIGNED        1
  37 #define FT_FRAME_OP_LITTLE        2
  38 #define FT_FRAME_OP_COMMAND( x )  ( x >> FT_FRAME_OP_SHIFT )
  39
  40 #define FT_MAKE_FRAME_OP( command, little, sign ) \
  41           ( ( command << FT_FRAME_OP_SHIFT ) | ( little << 1 ) | sign )
  42
  43 #define FT_FRAME_OP_END   0
  44 #define FT_FRAME_OP_START 1  /* start a new frame     */
  45 #define FT_FRAME_OP_BYTE  2  /* read 1-byte value     */
  46 #define FT_FRAME_OP_SHORT 3  /* read 2-byte value     */
  47 #define FT_FRAME_OP_LONG  4  /* read 4-byte value     */
  48 #define FT_FRAME_OP_OFF3  5  /* read 3-byte value     */
  49 #define FT_FRAME_OP_BYTES 6  /* read a bytes sequence */
  50
  51
  52   typedef enum  FT_Frame_Op_
  53   {
  54     ft_frame_end       = 0,
  55     ft_frame_start     = FT_MAKE_FRAME_OP( FT_FRAME_OP_START, 0, 0 ),
  56
  57     ft_frame_byte      = FT_MAKE_FRAME_OP( FT_FRAME_OP_BYTE,  0, 0 ),
  58     ft_frame_schar     = FT_MAKE_FRAME_OP( FT_FRAME_OP_BYTE,  0, 1 ),
  59
  60     ft_frame_ushort_be = FT_MAKE_FRAME_OP( FT_FRAME_OP_SHORT, 0, 0 ),
  61     ft_frame_short_be  = FT_MAKE_FRAME_OP( FT_FRAME_OP_SHORT, 0, 1 ),
  62     ft_frame_ushort_le = FT_MAKE_FRAME_OP( FT_FRAME_OP_SHORT, 1, 0 ),
  63     ft_frame_short_le  = FT_MAKE_FRAME_OP( FT_FRAME_OP_SHORT, 1, 1 ),
  64
  65     ft_frame_ulong_be  = FT_MAKE_FRAME_OP( FT_FRAME_OP_LONG, 0, 0 ),
  66     ft_frame_ulong_le  = FT_MAKE_FRAME_OP( FT_FRAME_OP_LONG, 0, 1 ),
  67     ft_frame_long_be   = FT_MAKE_FRAME_OP( FT_FRAME_OP_LONG, 1, 0 ),
  68     ft_frame_long_le   = FT_MAKE_FRAME_OP( FT_FRAME_OP_LONG, 1, 1 ),
  69
  70     ft_frame_uoff3_be  = FT_MAKE_FRAME_OP( FT_FRAME_OP_OFF3, 0, 0 ),
  71     ft_frame_uoff3_le  = FT_MAKE_FRAME_OP( FT_FRAME_OP_OFF3, 0, 1 ),
  72     ft_frame_off3_be   = FT_MAKE_FRAME_OP( FT_FRAME_OP_OFF3, 1, 0 ),
  73     ft_frame_off3_le   = FT_MAKE_FRAME_OP( FT_FRAME_OP_OFF3, 1, 1 ),
  74
  75     ft_frame_bytes     = FT_MAKE_FRAME_OP( FT_FRAME_OP_BYTES, 0, 0 ),
  76     ft_frame_skip      = FT_MAKE_FRAME_OP( FT_FRAME_OP_BYTES, 0, 1 )
  77
  78   } FT_Frame_Op;
  79
  80
  81   typedef struct  FT_Frame_Field_
  82   {
  83     FT_Frame_Op  value;
  84     char         size;
  85     FT_UShort    offset;
  86
  87   } FT_Frame_Field;
  88
  89
  90   /* make-up a FT_Frame_Field out of a structure type and a field name */
  91 #define FT_FIELD_REF( s, f )  (((s*)0)->f)
  92
  93 #define FT_FRAME_FIELD( frame_op, struct_type, field )            \
  94           {                                                       \
  95             frame_op,                                             \
  96             sizeof ( FT_FIELD_REF( struct_type,field ) ),         \
  97             (FT_UShort)(char*)&FT_FIELD_REF( struct_type, field ) \
  98           }
  99
 100 #define FT_MAKE_EMPTY_FIELD( frame_op )  { frame_op, 0, 0 }
 101
 102 #define FT_FRAME_START( s )         { ft_frame_start, 0, s }
 103 #define FT_FRAME_END                { ft_frame_end, 0, 0 }
 104
 105 #define FT_FRAME_LONG( s, f )       FT_FRAME_FIELD( ft_frame_long_be, s, f )
 106 #define FT_FRAME_ULONG( s, f )      FT_FRAME_FIELD( ft_frame_ulong_be, s, f )
 107 #define FT_FRAME_SHORT( s, f )      FT_FRAME_FIELD( ft_frame_short_be, s, f )
 108 #define FT_FRAME_USHORT( s, f )     FT_FRAME_FIELD( ft_frame_ushort_be, s, f )
 109 #define FT_FRAME_BYTE( s, f )       FT_FRAME_FIELD( ft_frame_byte, s, f )
 110 #define FT_FRAME_CHAR( s, f )       FT_FRAME_FIELD( ft_frame_schar, s, f )
 111
 112 #define FT_FRAME_LONG_LE( s, f )    FT_FRAME_FIELD( ft_frame_long_le, s, f )
 113 #define FT_FRAME_ULONG_LE( s, f )   FT_FRAME_FIELD( ft_frame_ulong_le, s, f )
 114 #define FT_FRAME_SHORT_LE( s, f )   FT_FRAME_FIELD( ft_frame_short_le, s, f )
 115 #define FT_FRAME_USHORT_LE( s, f )  FT_FRAME_FIELD( ft_frame_ushort_le, s, f )
 116
 117 #define FT_FRAME_SKIP_LONG          { ft_frame_long_be, 0, 0 }
 118 #define FT_FRAME_SKIP_SHORT         { ft_frame_short_be, 0, 0 }
 119 #define FT_FRAME_SKIP_BYTE          { ft_frame_byte, 0, 0 }
 120
 121 #define FT_FRAME_BYTES( struct_type, field, count )               \
 122           {                                                       \
 123             ft_frame_bytes,                                       \
 124             count,                                                \
 125             (FT_UShort)(char*)&FT_FIELD_REF( struct_type, field ) \
 126           }
 127 #define FT_FRAME_SKIP_BYTES( count )  { ft_frame_skip, count, 0 }
 128
 129
 130
 131   /*************************************************************************/
 132   /*                                                                       */
 133   /* integer extraction macros -- the `buffer' parameter must ALWAYS be of */
 134   /* type `char*' or equivalent (1-byte elements).                         */
 135   /*                                                                       */
 136 #define NEXT_Char( buffer )            \
 137           ( (signed char)*buffer++ )
 138 #define NEXT_Byte( buffer )            \
 139           ( (unsigned char)*buffer++ )
 140
 141 #define NEXT_Short( buffer )                              \
 142           ( buffer += 2,                                  \
 143             ( (short)( (signed   char)buffer[-2] << 8 ) | \
 144                        (unsigned char)buffer[-1]        ) )
 145
 146 #define NEXT_UShort( buffer )                      \
 147           ( (unsigned short)NEXT_Short( buffer ) )
 148
 149 #define NEXT_Offset( buffer )                             \
 150           ( buffer += 3,                                  \
 151             ( ( (long)(signed   char)buffer[-3] << 16 ) | \
 152               ( (long)(unsigned char)buffer[-2] <<  8 ) | \
 153                 (long)(unsigned char)buffer[-1]         ) )
 154
 155 #define NEXT_UOffset( buffer )                     \
 156           ( (unsigned long)NEXT_Offset( buffer ) )
 157
 158 #define NEXT_Long( buffer )                               \
 159           ( buffer += 4,                                  \
 160             ( ( (long)(signed   char)buffer[-4] << 24 ) | \
 161               ( (long)(unsigned char)buffer[-3] << 16 ) | \
 162               ( (long)(unsigned char)buffer[-2] <<  8 ) | \
 163                 (long)(unsigned char)buffer[-1]         ) )
 164
 165 #define NEXT_ULong( buffer )                     \
 166           ( (unsigned long)NEXT_Long( buffer ) )
 167
 168
 169 #define NEXT_ShortLE( buffer )                            \
 170           ( buffer += 2,                                  \
 171             ( (short)( (signed   char)buffer[-1] << 8 ) | \
 172                        (unsigned char)buffer[-2]        ) )
 173
 174 #define NEXT_UShortLE( buffer )                      \
 175           ( (unsigned short)NEXT_ShortLE( buffer ) )
 176
 177 #define NEXT_OffsetLE( buffer )                           \
 178           ( buffer += 3,                                  \
 179             ( ( (long)(signed   char)buffer[-1] << 16 ) | \
 180               ( (long)(unsigned char)buffer[-2] <<  8 ) | \
 181                 (long)(unsigned char)buffer[-3]         ) )
 182
 183 #define NEXT_UOffsetLE( buffer )                     \
 184           ( (unsigned long)NEXT_OffsetLE( buffer ) )
 185
 186
 187 #define NEXT_LongLE( buffer )                             \
 188           ( buffer += 4,                                  \
 189             ( ( (long)(signed   char)buffer[-1] << 24 ) | \
 190               ( (long)(unsigned char)buffer[-2] << 16 ) | \
 191               ( (long)(unsigned char)buffer[-3] <<  8 ) | \
 192                 (long)(unsigned char)buffer[-4]         ) )
 193
 194 #define NEXT_ULongLE( buffer )                     \
 195           ( (unsigned long)NEXT_LongLE( buffer ) )
 196
 197
 198   /*************************************************************************/
 199   /*                                                                       */
 200   /* Each GET_xxxx() macro uses an implicit `stream' variable.             */
 201   /*                                                                       */
 202 #define FT_GET_MACRO( func, type )        ( (type)func( stream ) )
 203
 204 #define GET_Char()      FT_GET_MACRO( FT_Get_Char, FT_Char )
 205 #define GET_Byte()      FT_GET_MACRO( FT_Get_Char, FT_Byte )
 206 #define GET_Short()     FT_GET_MACRO( FT_Get_Short, FT_Short )
 207 #define GET_UShort()    FT_GET_MACRO( FT_Get_Short, FT_UShort )
 208 #define GET_Offset()    FT_GET_MACRO( FT_Get_Offset, FT_Long )
 209 #define GET_UOffset()   FT_GET_MACRO( FT_Get_Offset, FT_ULong )
 210 #define GET_Long()      FT_GET_MACRO( FT_Get_Long, FT_Long )
 211 #define GET_ULong()     FT_GET_MACRO( FT_Get_Long, FT_ULong )
 212 #define GET_Tag4()      FT_GET_MACRO( FT_Get_Long, FT_ULong )
 213
 214 #define GET_ShortLE()   FT_GET_MACRO( FT_Get_ShortLE, FT_Short )
 215 #define GET_UShortLE()  FT_GET_MACRO( FT_Get_ShortLE, FT_UShort )
 216 #define GET_LongLE()    FT_GET_MACRO( FT_Get_LongLE, FT_Short )
 217 #define GET_ULongLE()   FT_GET_MACRO( FT_Get_LongLE, FT_Short )
 218
 219 #define FT_READ_MACRO( func, type, var )        \
 220           ( var = (type)func( stream, &error ), \
 221             error != FT_Err_Ok )
 222
 223 #define READ_Byte( var )      FT_READ_MACRO( FT_Read_Char, FT_Byte, var )
 224 #define READ_Char( var )      FT_READ_MACRO( FT_Read_Char, FT_Char, var )
 225 #define READ_Short( var )     FT_READ_MACRO( FT_Read_Short, FT_Short, var )
 226 #define READ_UShort( var )    FT_READ_MACRO( FT_Read_Short, FT_UShort, var )
 227 #define READ_Offset( var )    FT_READ_MACRO( FT_Read_Offset, FT_Long, var )
 228 #define READ_UOffset( var )   FT_READ_MACRO( FT_Read_Offset, FT_ULong, var )
 229 #define READ_Long( var )      FT_READ_MACRO( FT_Read_Long, FT_Long, var )
 230 #define READ_ULong( var )     FT_READ_MACRO( FT_Read_Long, FT_ULong, var )
 231
 232 #define READ_ShortLE( var )   FT_READ_MACRO( FT_Read_ShortLE, FT_Short, var )
 233 #define READ_UShortLE( var )  FT_READ_MACRO( FT_Read_ShortLE, FT_UShort, var )
 234 #define READ_LongLE( var )    FT_READ_MACRO( FT_Read_LongLE, FT_Long, var )
 235 #define READ_ULongLE( var )   FT_READ_MACRO( FT_Read_LongLE, FT_ULong, var )
 236
 237
 238   BASE_DEF( void )  FT_New_Memory_Stream( FT_Library  library,
 239                                           FT_Byte*    base,
 240                                           FT_ULong    size,
 241                                           FT_Stream   stream );
 242
 243   BASE_DEF( FT_Error )  FT_Seek_Stream( FT_Stream  stream,
 244                                         FT_ULong   pos );
 245
 246   BASE_DEF( FT_Error )  FT_Skip_Stream( FT_Stream  stream,
 247                                         FT_Long    distance );
 248
 249   BASE_DEF( FT_Long )  FT_Stream_Pos( FT_Stream  stream );
 250
 251
 252   BASE_DEF( FT_Error )  FT_Read_Stream( FT_Stream  stream,
 253                                         FT_Byte*   buffer,
 254                                         FT_ULong   count );
 255
 256   BASE_DEF( FT_Error )  FT_Read_Stream_At( FT_Stream  stream,
 257                                            FT_ULong   pos,
 258                                            FT_Byte*   buffer,
 259                                            FT_ULong   count );
 260
 261   BASE_DEF( FT_Error )  FT_Access_Frame( FT_Stream  stream,
 262                                          FT_ULong   count );
 263
 264   BASE_DEF( void )  FT_Forget_Frame( FT_Stream  stream );
 265
 266   BASE_DEF( FT_Error )  FT_Extract_Frame( FT_Stream  stream,
 267                                           FT_ULong   count,
 268                                           FT_Byte**  pbytes );
 269
 270   BASE_DEF( void )  FT_Release_Frame( FT_Stream  stream,
 271                                       FT_Byte**  pbytes );
 272
 273   BASE_DEF( FT_Char )  FT_Get_Char( FT_Stream  stream );
 274
 275   BASE_DEF( FT_Short )  FT_Get_Short( FT_Stream  stream );
 276
 277   BASE_DEF( FT_Long )  FT_Get_Offset( FT_Stream  stream );
 278
 279   BASE_DEF( FT_Long )  FT_Get_Long( FT_Stream  stream );
 280
 281   BASE_DEF( FT_Short )  FT_Get_ShortLE( FT_Stream  stream );
 282
 283   BASE_DEF( FT_Long )  FT_Get_LongLE( FT_Stream  stream );
 284
 285
 286   BASE_DEF( FT_Char )  FT_Read_Char( FT_Stream  stream,
 287                                      FT_Error*  error );
 288
 289   BASE_DEF( FT_Short )  FT_Read_Short( FT_Stream  stream,
 290                                        FT_Error*  error );
 291
 292   BASE_DEF( FT_Long )  FT_Read_Offset( FT_Stream  stream,
 293                                        FT_Error*  error );
 294
 295   BASE_DEF( FT_Long )  FT_Read_Long( FT_Stream  stream,
 296                                      FT_Error*  error );
 297
 298   BASE_DEF( FT_Short )  FT_Read_ShortLE( FT_Stream  stream,
 299                                          FT_Error*  error );
 300
 301   BASE_DEF( FT_Long )  FT_Read_LongLE( FT_Stream  stream,
 302                                        FT_Error*  error );
 303
 304   BASE_DEF( FT_Error )  FT_Read_Fields( FT_Stream              stream,
 305                                         const FT_Frame_Field*  fields,
 306                                         void*                  structure );
 307
 308
 309 #define USE_Stream( resource, stream )                       \
 310           FT_SET_ERROR( FT_Open_Stream( resource, stream ) )
 311
 312 #define DONE_Stream( stream )      \
 313           FT_Done_Stream( stream )
 314
 315
 316 #define ACCESS_Frame( size )                              \
 317           FT_SET_ERROR( FT_Access_Frame( stream, size ) )
 318
 319 #define FORGET_Frame()              \
 320           FT_Forget_Frame( stream )
 321
 322 #define EXTRACT_Frame( size, bytes )                              \
 323           FT_SET_ERROR( FT_Extract_Frame( stream, size,           \
 324                                           (FT_Byte**)&(bytes) ) )
 325
 326 #define RELEASE_Frame( bytes )                            \
 327           FT_Release_Frame( stream, (FT_Byte**)&(bytes) )
 328
 329 #define FILE_Seek( position )                                \
 330           FT_SET_ERROR( FT_Seek_Stream( stream, position ) )
 331
 332 #define FILE_Skip( distance )                                \
 333           FT_SET_ERROR( FT_Skip_Stream( stream, distance ) )
 334
 335 #define FILE_Pos()                \
 336           FT_Stream_Pos( stream )
 337
 338 #define FILE_Read( buffer, count )                        \
 339           FT_SET_ERROR( FT_Read_Stream( stream,           \
 340                                         (FT_Byte*)buffer, \
 341                                         count ) )
 342
 343 #define FILE_Read_At( position, buffer, count )              \
 344           FT_SET_ERROR( FT_Read_Stream_At( stream,           \
 345                                            position,         \
 346                                            (FT_Byte*)buffer, \
 347                                            count ) )
 348
 349 #define READ_Fields( fields, object )  \
 350         ( ( error = FT_Read_Fields( stream, fields, object ) ) != FT_Err_Ok )
 351
 352
 353 #ifdef __cplusplus
 354   }
 355 #endif
 356
 357
 358 #endif /* FTSTREAM_H */
 359
 360
 361 /* END */