psobjs.c

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        break;

      if ( !IS_PS_XDIGIT( *cur ) )
        break;
    }

    if ( cur < limit && *cur != '>' )
    {
      FT_ERROR(( "skip_string: missing closing delimiter `>'\n" ));
      err = PSaux_Err_Invalid_File_Format;
    }
    else
      cur++;

    *acur = cur;
    return err;
  }


  /* first character must be the opening brace that */
  /* starts the procedure                           */

  /* NB: [ and ] need not match:                    */
  /* `/foo {[} def' is a valid PostScript fragment, */
  /* even within a Type1 font                       */

  static FT_Error
  skip_procedure( FT_Byte*  *acur,
                  FT_Byte*   limit )
  {
    FT_Byte*  cur;
    FT_Int    embed = 0;
    FT_Error  error = PSaux_Err_Ok;


    FT_ASSERT( **acur == '{' );

    for ( cur = *acur; cur < limit && error == PSaux_Err_Ok; ++cur )
    {
      switch ( *cur )
      {
      case '{':
        ++embed;
        break;

      case '}':
        --embed;
        if ( embed == 0 )
        {
          ++cur;
          goto end;
        }
        break;

      case '(':
        error = skip_literal_string( &cur, limit );
        break;

      case '<':
        error = skip_string( &cur, limit );
        break;

      case '%':
        skip_comment( &cur, limit );
        break;
      }
    }

  end:
    if ( embed != 0 )
      error = PSaux_Err_Invalid_File_Format;

    *acur = cur;

    return error;
  }


  /***********************************************************************/
  /*                                                                     */
  /* All exported parsing routines handle leading whitespace and stop at */
  /* the first character which isn't part of the just handled token.     */
  /*                                                                     */
  /***********************************************************************/


  FT_LOCAL_DEF( void )
  ps_parser_skip_PS_token( PS_Parser  parser )
  {
    /* Note: PostScript allows any non-delimiting, non-whitespace        */
    /*       character in a name (PS Ref Manual, 3rd ed, p31).           */
    /*       PostScript delimiters are (, ), <, >, [, ], {, }, /, and %. */

    FT_Byte*  cur   = parser->cursor;
    FT_Byte*  limit = parser->limit;
    FT_Error  error = PSaux_Err_Ok;


    skip_spaces( &cur, limit );             /* this also skips comments */
    if ( cur >= limit )
      goto Exit;

    /* self-delimiting, single-character tokens */
    if ( *cur == '[' || *cur == ']' )
    {
      cur++;
      goto Exit;
    }

    /* skip balanced expressions (procedures and strings) */

    if ( *cur == '{' )                              /* {...} */
    {
      error = skip_procedure( &cur, limit );
      goto Exit;
    }

    if ( *cur == '(' )                              /* (...) */
    {
      error = skip_literal_string( &cur, limit );
      goto Exit;
    }

    if ( *cur == '<' )                              /* <...> */
    {
      if ( cur + 1 < limit && *(cur + 1) == '<' )   /* << */
      {
        cur++;
        cur++;
      }
      else
        error = skip_string( &cur, limit );

      goto Exit;
    }

    if ( *cur == '>' )
    {
      cur++;
      if ( cur >= limit || *cur != '>' )             /* >> */
      {
        FT_ERROR(( "ps_parser_skip_PS_token: "
                   "unexpected closing delimiter `>'\n" ));
        error = PSaux_Err_Invalid_File_Format;
        goto Exit;
      }
      cur++;
      goto Exit;
    }

    if ( *cur == '/' )
      cur++;

    /* anything else */
    while ( cur < limit )
    {
      /* *cur might be invalid (e.g., ')' or '}'), but this   */
      /* is handled by the test `cur == parser->cursor' below */
      if ( IS_PS_DELIM( *cur ) )
        break;

      cur++;
    }

  Exit:
    if ( cur == parser->cursor )
    {
      FT_ERROR(( "ps_parser_skip_PS_token: "
                 "current token is `%c', which is self-delimiting "
                 "but invalid at this point\n",
                 *cur ));

      error = PSaux_Err_Invalid_File_Format;
    }

    FT_ASSERT( parser->error == PSaux_Err_Ok );
    parser->error  = error;
    parser->cursor = cur;
  }


  FT_LOCAL_DEF( void )
  ps_parser_skip_spaces( PS_Parser  parser )
  {
    skip_spaces( &parser->cursor, parser->limit );
  }


  /* `token' here means either something between balanced delimiters */
  /* or the next token; the delimiters are not removed.              */

  FT_LOCAL_DEF( void )
  ps_parser_to_token( PS_Parser  parser,
                      T1_Token   token )
  {
    FT_Byte*  cur;
    FT_Byte*  limit;
    FT_Int    embed;


    token->type  = T1_TOKEN_TYPE_NONE;
    token->start = 0;
    token->limit = 0;

    /* first of all, skip leading whitespace */
    ps_parser_skip_spaces( parser );

    cur   = parser->cursor;
    limit = parser->limit;

    if ( cur >= limit )
      return;

    switch ( *cur )
    {
      /************* check for literal string *****************/
    case '(':
      token->type  = T1_TOKEN_TYPE_STRING;
      token->start = cur;

      if ( skip_literal_string( &cur, limit ) == PSaux_Err_Ok )
        token->limit = cur;
      break;

      /************* check for programs/array *****************/
    case '{':
      token->type  = T1_TOKEN_TYPE_ARRAY;
      token->start = cur;

      if ( skip_procedure( &cur, limit ) == PSaux_Err_Ok )
        token->limit = cur;
      break;

      /************* check for table/array ********************/
      /* XXX: in theory we should also look for "<<"          */
      /*      since this is semantically equivalent to "[";   */
      /*      in practice it doesn't matter (?)               */
    case '[':
      token->type  = T1_TOKEN_TYPE_ARRAY;
      embed        = 1;
      token->start = cur++;

      /* we need this to catch `[ ]' */
      parser->cursor = cur;
      ps_parser_skip_spaces( parser );
      cur = parser->cursor;

      while ( cur < limit && !parser->error )
      {
        /* XXX: this is wrong because it does not      */
        /*      skip comments, procedures, and strings */
        if ( *cur == '[' )
          embed++;
        else if ( *cur == ']' )
        {
          embed--;
          if ( embed <= 0 )
          {
            token->limit = ++cur;
            break;
          }
        }

        parser->cursor = cur;
        ps_parser_skip_PS_token( parser );
        /* we need this to catch `[XXX ]' */
        ps_parser_skip_spaces  ( parser );
        cur = parser->cursor;
      }
      break;

      /* ************ otherwise, it is any token **************/
    default:
      token->start = cur;
      token->type  = ( *cur == '/' ? T1_TOKEN_TYPE_KEY : T1_TOKEN_TYPE_ANY );
      ps_parser_skip_PS_token( parser );
      cur = parser->cursor;
      if ( !parser->error )
        token->limit = cur;
    }

    if ( !token->limit )
    {
      token->start = 0;
      token->type  = T1_TOKEN_TYPE_NONE;
    }

    parser->cursor = cur;
  }


  /* NB: `tokens' can be NULL if we only want to count */
  /* the number of array elements                      */

  FT_LOCAL_DEF( void )
  ps_parser_to_token_array( PS_Parser  parser,
                            T1_Token   tokens,
                            FT_UInt    max_tokens,
                            FT_Int*    pnum_tokens )
  {
    T1_TokenRec  master;


    *pnum_tokens = -1;

    /* this also handles leading whitespace */
    ps_parser_to_token( parser, &master );

    if ( master.type == T1_TOKEN_TYPE_ARRAY )
    {
      FT_Byte*  old_cursor = parser->cursor;
      FT_Byte*  old_limit  = parser->limit;
      T1_Token  cur        = tokens;
      T1_Token  limit      = cur + max_tokens;


      /* don't include outermost delimiters */
      parser->cursor = master.start + 1;
      parser->limit  = master.limit - 1;

      while ( parser->cursor < parser->limit )
      {
        T1_TokenRec  token;


        ps_parser_to_token( parser, &token );
        if ( !token.type )
          break;

        if ( tokens != NULL && cur < limit )
          *cur = token;

        cur++;
      }

      *pnum_tokens = (FT_Int)( cur - tokens );

      parser->cursor = old_cursor;
      parser->limit  = old_limit;
    }
  }


  /* first character must be a delimiter or a part of a number */
  /* NB: `coords' can be NULL if we just want to skip the      */
  /*     array; in this case we ignore `max_coords'            */

  static FT_Int
  ps_tocoordarray( FT_Byte*  *acur,
                   FT_Byte*   limit,
                   FT_Int     max_coords,
                   FT_Short*  coords )
  {
    FT_Byte*  cur   = *acur;
    FT_Int    count = 0;
    FT_Byte   c, ender;


    if ( cur >= limit )
      goto Exit;

    /* check for the beginning of an array; otherwise, only one number */
    /* will be read                                                    */
    c     = *cur;
    ender = 0;

    if ( c == '[' )
      ender = ']';

    if ( c == '{' )
      ender = '}';

    if ( ender )
      cur++;

    /* now, read the coordinates */
    while ( cur < limit )
    {
      FT_Short dummy;


      /* skip whitespace in front of data */
      skip_spaces( &cur, limit );
      if ( cur >= limit )
        goto Exit;

      if ( coords != NULL && count >= max_coords )
        break;

      if ( *cur == ender )
      {
        cur++;
        break;
      }

      /* call PS_Conv_ToFixed() even if coords == NULL */
      /* to properly parse number at `cur'             */
      *( coords != NULL ? &coords[count] : &dummy ) =
        (FT_Short)( PS_Conv_ToFixed( &cur, limit, 0 ) >> 16 );
      count++;

      if ( !ender )
        break;
    }

  Exit:
    *acur = cur;
    return count;
  }


  /* first character must be a delimiter or a part of a number */
  /* NB: `values' can be NULL if we just want to skip the      */
  /*     array in this case we ignore `max_values'             */

  static FT_Int
  ps_tofixedarray( FT_Byte*  *acur,
                   FT_Byte*   limit,
                   FT_Int     max_values,