ftsystem.c.svn-base

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  /*                                                                       */
  /* <Description>                                                         */
  /*    The function to close a stream which is created by ft_alloc.       */
  /*                                                                       */
  /* <Input>                                                               */
  /*    stream :: A pointer to the stream object.                          */
  /*                                                                       */
  FT_CALLBACK_DEF( void )
  ft_close_stream_by_free( FT_Stream  stream )
  {
    ft_free( NULL, stream->descriptor.pointer );

    stream->descriptor.pointer = NULL;
    stream->size               = 0;
    stream->base               = 0;
  }


  /* documentation is in ftobjs.h */

  FT_BASE_DEF( FT_Error )
  FT_Stream_Open( FT_Stream    stream,
                  const char*  filepathname )
  {
    int          file;
    struct stat  stat_buf;


    if ( !stream )
      return FT_Err_Invalid_Stream_Handle;

    /* open the file */
    file = open( filepathname, O_RDONLY );
    if ( file < 0 )
    {
      FT_ERROR(( "FT_Stream_Open:" ));
      FT_ERROR(( " could not open `%s'\n", filepathname ));
      return FT_Err_Cannot_Open_Resource;
    }

    /* Here we ensure that a "fork" will _not_ duplicate   */
    /* our opened input streams on Unix.  This is critical */
    /* since it avoids some (possible) access control      */
    /* issues and cleans up the kernel file table a bit.   */
    /*                                                     */
#ifdef F_SETFD
#ifdef FD_CLOEXEC
    (void)fcntl( file, F_SETFD, FD_CLOEXEC );
#else
    (void)fcntl( file, F_SETFD, 1 );
#endif /* FD_CLOEXEC */
#endif /* F_SETFD */

    if ( fstat( file, &stat_buf ) < 0 )
    {
      FT_ERROR(( "FT_Stream_Open:" ));
      FT_ERROR(( " could not `fstat' file `%s'\n", filepathname ));
      goto Fail_Map;
    }

    /* XXX: TODO -- real 64bit platform support                        */
    /*                                                                 */
    /* `stream->size' is typedef'd to unsigned long (in                */
    /* freetype/ftsystem.h); `stat_buf.st_size', however, is usually   */
    /* typedef'd to off_t (in sys/stat.h).                             */
    /* On some platforms, the former is 32bit and the latter is 64bit. */
    /* To avoid overflow caused by fonts in huge files larger than     */
    /* 2GB, do a test.  Temporary fix proposed by Sean McBride.        */
    /*                                                                 */
    if ( stat_buf.st_size > LONG_MAX )
    {
      FT_ERROR(( "FT_Stream_Open: file is too big" ));
      goto Fail_Map;
    }

    /* This cast potentially truncates a 64bit to 32bit! */
    stream->size = (unsigned long)stat_buf.st_size;
    stream->pos  = 0;
    stream->base = (unsigned char *)mmap( NULL,
                                          stream->size,
                                          PROT_READ,
                                          MAP_FILE | MAP_PRIVATE,
                                          file,
                                          0 );

    /* on some RTOS, mmap might return 0 */
    if ( (long)stream->base != -1 && stream->base != NULL )
      stream->close = ft_close_stream_by_munmap;
    else
    {
      ssize_t  total_read_count;


      FT_ERROR(( "FT_Stream_Open:" ));
      FT_ERROR(( " could not `mmap' file `%s'\n", filepathname ));

      stream->base = (unsigned char*)ft_alloc( NULL, stream->size );

      if ( !stream->base )
      {
        FT_ERROR(( "FT_Stream_Open:" ));
        FT_ERROR(( " could not `alloc' memory\n" ));
        goto Fail_Map;
      }

      total_read_count = 0;
      do {
        ssize_t  read_count;


        read_count = read( file,
                           stream->base + total_read_count,
                           stream->size - total_read_count );

        if ( read_count <= 0 )
        {
          if ( read_count == -1 && errno == EINTR )
            continue;

          FT_ERROR(( "FT_Stream_Open:" ));
          FT_ERROR(( " error while `read'ing file `%s'\n", filepathname ));
          goto Fail_Read;
        }

        total_read_count += read_count;

      } while ( (unsigned long)total_read_count != stream->size );

      stream->close = ft_close_stream_by_free;
    }

    close( file );

    stream->descriptor.pointer = stream->base;
    stream->pathname.pointer   = (char*)filepathname;

    stream->read = 0;

    FT_TRACE1(( "FT_Stream_Open:" ));
    FT_TRACE1(( " opened `%s' (%d bytes) successfully\n",
                filepathname, stream->size ));

    return FT_Err_Ok;

  Fail_Read:
    ft_free( NULL, stream->base );

  Fail_Map:
    close( file );

    stream->base = NULL;
    stream->size = 0;
    stream->pos  = 0;

    return FT_Err_Cannot_Open_Stream;
  }


#ifdef FT_DEBUG_MEMORY

  extern FT_Int
  ft_mem_debug_init( FT_Memory  memory );

  extern void
  ft_mem_debug_done( FT_Memory  memory );

#endif


  /* documentation is in ftobjs.h */

  FT_BASE_DEF( FT_Memory )
  FT_New_Memory( void )
  {
    FT_Memory  memory;


    memory = (FT_Memory)malloc( sizeof ( *memory ) );
    if ( memory )
    {
      memory->user    = 0;
      memory->alloc   = ft_alloc;
      memory->realloc = ft_realloc;
      memory->free    = ft_free;
#ifdef FT_DEBUG_MEMORY
      ft_mem_debug_init( memory );
#endif
    }

    return memory;
  }


  /* documentation is in ftobjs.h */

  FT_BASE_DEF( void )
  FT_Done_Memory( FT_Memory  memory )
  {
#ifdef FT_DEBUG_MEMORY
    ft_mem_debug_done( memory );
#endif
    memory->free( memory, memory );
  }


/* END */