bdflib.c

下载来的一个看图软件的源代码

      /* Resize the list if necessary. */
      if ( list->used == list->size )
      {
        if ( list->size == 0 )
        {
          if ( FT_NEW_ARRAY( list->field, 5 ) )
            goto Exit;
        }
        else
        {
          if ( FT_RENEW_ARRAY ( list->field ,
                                list->size,
                                list->size + 5 ) )
            goto Exit;
        }

        list->size += 5;
      }

      /* Assign the field appropriately. */
      list->field[list->used++] = ( ep > sp ) ? sp : empty;

      sp = ep;

      if ( mult )
      {
        /* If multiple separators should be collapsed, do it now by */
        /* setting all the separator characters to 0.               */
        for ( ; *ep && sbitset( seps, *ep ); ep++ )
          *ep = 0;
      }
      else if ( *ep != 0 )
        /* Don't collapse multiple separators by making them 0, so just */
        /* make the one encountered 0.                                  */
        *ep++ = 0;

      final_empty = ( ep > sp && *ep == 0 );
      sp = ep;
    }

    /* Finally, NULL-terminate the list. */
    if ( list->used + final_empty + 1 >= list->size )
    {
      if ( list->used == list->size )
      {
        if ( list->size == 0 )
        {
          if ( FT_NEW_ARRAY( list->field, 5 ) )
            goto Exit;
        }
        else
        {
          if ( FT_RENEW_ARRAY( list->field,
                               list->size,
                               list->size + 5 ) )
            goto Exit;
        }

        list->size += 5;
      }
    }

    if ( final_empty )
      list->field[list->used++] = empty;

    if ( list->used == list->size )
    {
      if ( list->size == 0 )
      {
        if ( FT_NEW_ARRAY( list->field, 5 ) )
          goto Exit;
      }
      else
      {
        if ( FT_RENEW_ARRAY( list->field,
                             list->size,
                             list->size + 5 ) )
          goto Exit;
      }

      list->size += 5;
    }

    list->field[list->used] = 0;

  Exit:
    return error;
  }


  static void
  _bdf_shift( unsigned long  n,
              _bdf_list_t*   list )
  {
    unsigned long  i, u;


    if ( list == 0 || list->used == 0 || n == 0 )
      return;

    if ( n >= list->used )
    {
      list->used = 0;
      return;
    }

    for ( u = n, i = 0; u < list->used; i++, u++ )
      list->field[i] = list->field[u];
    list->used -= n;
  }


  static char *
  _bdf_join( int             c,
             unsigned long*  len,
             _bdf_list_t*    list )
  {
    unsigned long  i, j;
    char           *fp, *dp;


    if ( list == 0 || list->used == 0 )
      return 0;

    *len = 0;

    dp = list->field[0];
    for ( i = j = 0; i < list->used; i++ )
    {
      fp = list->field[i];
      while ( *fp )
        dp[j++] = *fp++;

      if ( i + 1 < list->used )
        dp[j++] = (char)c;
    }
    dp[j] = 0;

    *len = j;
    return dp;
  }


  /* High speed file reader that passes each line to a callback. */
  static FT_Error
  bdf_internal_readstream( FT_Stream  stream,
                           char*      buffer,
                           int        count,
                           int       *read_bytes )
  {
    int            rbytes;
    unsigned long  pos   = stream->pos;
    FT_Error       error = BDF_Err_Ok;


    if ( pos > stream->size )
    {
      FT_ERROR(( "bdf_internal_readstream:" ));
      FT_ERROR(( " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
                 pos, stream->size ));
      error = BDF_Err_Invalid_Stream_Operation;
      goto Exit;
    }

    if ( stream->read )
      rbytes = stream->read( stream, pos,
                             (unsigned char *)buffer, count );
    else
    {
      rbytes = stream->size - pos;
      if ( rbytes > count )
        rbytes = count;

      FT_MEM_COPY( buffer, stream->base + pos, rbytes );
    }

    stream->pos = pos + rbytes;

    *read_bytes = rbytes;

  Exit:
    return error;
  }


  static FT_Error
  _bdf_readstream( FT_Stream         stream,
                   _bdf_line_func_t  callback,
                   void*             client_data,
                   unsigned long    *lno )
  {
    _bdf_line_func_t  cb;
    unsigned long     lineno;
    int               n, done, refill, bytes, hold;
    char              *ls, *le, *pp, *pe, *hp;
    char              *buf = 0;
    FT_Memory         memory = stream->memory;
    FT_Error          error = BDF_Err_Ok;


    if ( callback == 0 )
    {
      error = BDF_Err_Invalid_Argument;
      goto Exit;
    }

    if ( FT_NEW_ARRAY( buf, 65536L ) )
      goto Exit;

    cb     = callback;
    lineno = 1;
    buf[0] = 0;

    done = 0;
    pp = ls = le = buf;

    bytes = 65536L;

    while ( !done )
    {
      error = bdf_internal_readstream( stream, pp, bytes, &n );
      if ( error )
        goto Exit;

      if ( n == 0 )
        break;

      /* Determine the new end of the buffer pages. */
      pe = pp + n;

      for ( refill = 0; done == 0 && refill == 0; )
      {
        while ( le < pe && *le != '\n' && *le != '\r' )
          le++;

        if ( le == pe )
        {
          /* Hit the end of the last page in the buffer.  Need to find */
          /* out how many pages to shift and how many pages need to be */
          /* read in.  Adjust the line start and end pointers down to  */
          /* point to the right places in the pages.                   */

          pp  = buf + ( ( ( ls - buf ) >> 13 ) << 13 );
          n   = pp - buf;
          ls -= n;
          le -= n;
          n   = pe - pp;

          FT_MEM_MOVE( buf, pp, n );

          pp     = buf + n;
          bytes  = 65536L - n;
          refill = 1;
        }
        else
        {
          /* Temporarily NULL-terminate the line. */
          hp   = le;
          hold = *le;
          *le  = 0;

          /* XXX: Use encoding independent value for 0x1a */
          if ( *ls != '#' && *ls != 0x1a                          &&
               le > ls                                            &&
               ( error = (*cb)( ls, le - ls, lineno, (void *)&cb,
                                client_data ) ) != BDF_Err_Ok     )
            done = 1;
          else
          {
            ls = ++le;
            /* Handle the case of DOS crlf sequences. */
            if ( le < pe && hold == '\n' && *le =='\r' )
              ls = ++le;
          }

          /* Increment the line number. */
          lineno++;

          /* Restore the character at the end of the line. */
          *hp = (char)hold;
        }
      }
    }

    *lno             = lineno;

  Exit:
    FT_FREE( buf );
    return error;
  }


  /* XXX: make this work with EBCDIC also */

  static const unsigned char  a2i[128] =
  {
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
  };

  static const unsigned char  odigits[32] =
  {
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  };

  static const unsigned char  ddigits[32] =
  {
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0x03,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  };

  static const unsigned char  hdigits[32] =
  {
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0x03,
    0x7e, 0x00, 0x00, 0x00, 0x7e, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  };


#define isdigok( m, d )  (m[(d) >> 3] & ( 1 << ( (d) & 7 ) ) )


  /* Routine to convert an ASCII string into an unsigned long integer. */
  static unsigned long
  _bdf_atoul( char*   s,
              char**  end,
              int     base )
  {
    unsigned long         v;
    const unsigned char*  dmap;


    if ( s == 0 || *s == 0 )
      return 0;

    /* Make sure the radix is something recognizable.  Default to 10. */
    switch ( base )
    {
    case 8:
      dmap = odigits;
      break;
    case 16:
      dmap = hdigits;
      break;
    default:
      base = 10;
      dmap = ddigits;
      break;
    }

    /* Check for the special hex prefix. */
    if ( *s == '0'                                  &&
         ( *( s + 1 ) == 'x' || *( s + 1 ) == 'X' ) )
    {
      base = 16;
      dmap = hdigits;
      s   += 2;
    }

    for ( v = 0; isdigok( dmap, *s ); s++ )
      v = v * base + a2i[(int)*s];

    if ( end != 0 )
      *end = s;

    return v;
  }


  /* Routine to convert an ASCII string into an signed long integer. */
  static long
  _bdf_atol( char*   s,
             char**  end,
             int     base )
  {
    long                  v, neg;
    const unsigned char*  dmap;


    if ( s == 0 || *s == 0 )
      return 0;

    /* Make sure the radix is something recognizable.  Default to 10. */
    switch ( base )
    {
    case 8:
      dmap = odigits;
      break;
    case 16:
      dmap = hdigits;
      break;
    default:
      base = 10;
      dmap = ddigits;
      break;
    }

    /* Check for a minus sign. */
    neg = 0;
    if ( *s == '-' )
    {
      s++;
      neg = 1;
    }

    /* Check for the special hex prefix. */
    if ( *s == '0'                                  &&
         ( *( s + 1 ) == 'x' || *( s + 1 ) == 'X' ) )
    {
      base = 16;
      dmap = hdigits;
      s   += 2;
    }

    for ( v = 0; isdigok( dmap, *s ); s++ )
      v = v * base + a2i[(int)*s];

    if ( end != 0 )
      *end = s;

    return ( !neg ) ? v : -v;
  }


  /* Routine to convert an ASCII string into an signed short integer. */
  static short
  _bdf_atos( char*   s,
             char**  end,
             int     base )
  {
    short                 v, neg;
    const unsigned char*  dmap;