psobjs.c

下载来的一个看图软件的源代码

/***************************************************************************/
/*                                                                         */
/*  psobjs.c                                                               */
/*                                                                         */
/*    Auxiliary functions for PostScript fonts (body).                     */
/*                                                                         */
/*  Copyright 1996-2001, 2002, 2003 by                                     */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#include <ft2build.h>
#include FT_INTERNAL_POSTSCRIPT_AUX_H
#include FT_INTERNAL_DEBUG_H

#include "psobjs.h"

#include "psauxerr.h"


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                             PS_TABLE                          *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    ps_table_new                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a PS_Table.                                            */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    table  :: The address of the target table.                         */
  /*                                                                       */
  /* <Input>                                                               */
  /*    count  :: The table size = the maximum number of elements.         */
  /*                                                                       */
  /*    memory :: The memory object to use for all subsequent              */
  /*              reallocations.                                           */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  ps_table_new( PS_Table   table,
                FT_Int     count,
                FT_Memory  memory )
  {
    FT_Error  error;


    table->memory = memory;
    if ( FT_NEW_ARRAY( table->elements, count ) ||
         FT_NEW_ARRAY( table->lengths,  count ) )
      goto Exit;

    table->max_elems = count;
    table->init      = 0xDEADBEEFUL;
    table->num_elems = 0;
    table->block     = 0;
    table->capacity  = 0;
    table->cursor    = 0;

    *(PS_Table_FuncsRec*)&table->funcs = ps_table_funcs;

  Exit:
    if ( error )
      FT_FREE( table->elements );

    return error;
  }


  static void
  shift_elements( PS_Table  table,
                  FT_Byte*  old_base )
  {
    FT_Long    delta  = (FT_Long)( table->block - old_base );
    FT_Byte**  offset = table->elements;
    FT_Byte**  limit  = offset + table->max_elems;


    for ( ; offset < limit; offset++ )
    {
      if ( offset[0] )
        offset[0] += delta;
    }
  }


  static FT_Error
  reallocate_t1_table( PS_Table  table,
                       FT_Long   new_size )
  {
    FT_Memory  memory   = table->memory;
    FT_Byte*   old_base = table->block;
    FT_Error   error;


    /* allocate new base block */
    if ( FT_ALLOC( table->block, new_size ) )
    {
      table->block = old_base;
      return error;
    }

    /* copy elements and shift offsets */
    if (old_base )
    {
      FT_MEM_COPY( table->block, old_base, table->capacity );
      shift_elements( table, old_base );
      FT_FREE( old_base );
    }

    table->capacity = new_size;

    return PSaux_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    ps_table_add                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Adds an object to a PS_Table, possibly growing its memory block.   */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    table  :: The target table.                                        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    idx  :: The index of the object in the table.                      */
  /*                                                                       */
  /*    object :: The address of the object to copy in memory.             */
  /*                                                                       */
  /*    length :: The length in bytes of the source object.                */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.  An error is returned if a  */
  /*    reallocation fails.                                                */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  ps_table_add( PS_Table    table,
                FT_Int      idx,
                void*       object,
                FT_PtrDist  length )
  {
    if ( idx < 0 || idx > table->max_elems )
    {
      FT_ERROR(( "ps_table_add: invalid index\n" ));
      return PSaux_Err_Invalid_Argument;
    }

    /* grow the base block if needed */
    if ( table->cursor + length > table->capacity )
    {
      FT_Error   error;
      FT_Offset  new_size  = table->capacity;
      FT_Long    in_offset;


      in_offset = (FT_Long)((FT_Byte*)object - table->block);
      if ( (FT_ULong)in_offset >= table->capacity )
        in_offset = -1;

      while ( new_size < table->cursor + length )
      {
        /* increase size by 25% and round up to the nearest multiple
           of 1024 */
        new_size += ( new_size >> 2 ) + 1;
        new_size  = ( new_size + 1023 ) & -1024;
      }

      error = reallocate_t1_table( table, new_size );
      if ( error )
        return error;

      if ( in_offset >= 0 )
        object = table->block + in_offset;
    }

    /* add the object to the base block and adjust offset */
    table->elements[idx] = table->block + table->cursor;
    table->lengths [idx] = length;
    FT_MEM_COPY( table->block + table->cursor, object, length );

    table->cursor += length;
    return PSaux_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    ps_table_done                                                      */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Finalizes a PS_TableRec (i.e., reallocate it to its current        */
  /*    cursor).                                                           */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    table :: The target table.                                         */
  /*                                                                       */
  /* <Note>                                                                */
  /*    This function does NOT release the heap's memory block.  It is up  */
  /*    to the caller to clean it, or reference it in its own structures.  */
  /*                                                                       */
  FT_LOCAL_DEF( void )
  ps_table_done( PS_Table  table )
  {
    FT_Memory  memory = table->memory;
    FT_Error   error;
    FT_Byte*   old_base = table->block;


    /* should never fail, because rec.cursor <= rec.size */
    if ( !old_base )
      return;

    if ( FT_ALLOC( table->block, table->cursor ) )
      return;
    FT_MEM_COPY( table->block, old_base, table->cursor );
    shift_elements( table, old_base );

    table->capacity = table->cursor;
    FT_FREE( old_base );

    FT_UNUSED( error );
  }


  FT_LOCAL_DEF( void )
  ps_table_release( PS_Table  table )
  {
    FT_Memory  memory = table->memory;


    if ( (FT_ULong)table->init == 0xDEADBEEFUL )
    {
      FT_FREE( table->block );
      FT_FREE( table->elements );
      FT_FREE( table->lengths );
      table->init = 0;
    }
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                            T1 PARSER                          *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* In the PostScript Language Reference Manual (PLRM) the following */
  /* characters are called `white-space characters'.                  */
#define IS_T1_WHITESPACE( c )  ( (c) == ' '  || (c) == '\t' )
#define IS_T1_LINESPACE( c )   ( (c) == '\r' || (c) == '\n' || (c) == '\f' )
#define IS_T1_NULLSPACE( c )   ( (c) == '\0' )

  /* According to the PLRM all white-space characters are equivalent, */
  /* except in comments and strings.                                  */
#define IS_T1_SPACE( c )  ( IS_T1_WHITESPACE( c ) || \
                            IS_T1_LINESPACE( c )  || \
                            IS_T1_NULLSPACE( c )  )


  static void
  skip_spaces( FT_Byte**  acur,
               FT_Byte*   limit )
  {
    FT_Byte* cur = *acur;


    while ( cur < limit )
    {
      FT_Byte  c = *cur;


      if ( !IS_T1_SPACE( c ) )
        break;
      cur++;
    }

    *acur = cur;
  }


  static void
  skip_alpha( FT_Byte**  acur,
              FT_Byte*   limit )
  {
    FT_Byte*  cur = *acur;


    while ( cur < limit )
    {
      FT_Byte  c = *cur;


      if ( IS_T1_SPACE( c ) )
        break;
      cur++;
    }

    *acur = cur;
  }


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


  FT_LOCAL_DEF( void )
  ps_parser_skip_alpha( PS_Parser  parser )
  {
    skip_alpha( &parser->cursor, parser->limit );
  }


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


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

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

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

    if ( cur < limit )
    {
      switch ( *cur )
      {
        /************* check for strings ***********************/
      case '(':
        token->type = T1_TOKEN_TYPE_STRING;
        ender = ')';
        goto Lookup_Ender;

        /************* check for programs/array ****************/
      case '{':
        token->type = T1_TOKEN_TYPE_ARRAY;
        ender = '}';
        goto Lookup_Ender;

        /************* check for table/array ******************/
      case '[':
        token->type = T1_TOKEN_TYPE_ARRAY;
        ender = ']';

      Lookup_Ender:
        embed   = 1;
        starter = *cur++;
        token->start = cur;
        while ( cur < limit )
        {
          if ( *cur == starter )
            embed++;
          else if ( *cur == ender )
          {
            embed--;
            if ( embed <= 0 )
            {
              token->limit = cur++;
              break;
            }
          }
          cur++;
        }
        break;

        /* **************** otherwise, it's any token **********/
      default:
        token->start = cur++;
        token->type  = T1_TOKEN_TYPE_ANY;
        while ( cur < limit && !IS_T1_SPACE( *cur ) )
          cur++;

        token->limit = cur;
      }

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

      parser->cursor = cur;
    }
  }


  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;

    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;


      parser->cursor = master.start;
      parser->limit  = master.limit;

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


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

        if ( cur < limit )
          *cur = token;

        cur++;
      }

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

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


  static FT_Long
  T1Radix( FT_Long    radixBase,
           FT_Byte**  cur,
           FT_Byte*   limit )
  {
    FT_Long  result = 0;
    FT_Byte  radixEndChar0 =
               (FT_Byte)( radixBase > 10 ? '9' + 1 : '0' + radixBase );
    FT_Byte  radixEndChar1 =
               (FT_Byte)( 'A' + radixBase - 10 );
    FT_Byte  radixEndChar2 =
               (FT_Byte)( 'a' + radixBase - 10 );


    while( *cur < limit )
    {
      if ( (*cur)[0] >= '0' && (*cur)[0] < radixEndChar0 )
        result = result * radixBase + (*cur)[0] - '0';

      else if ( radixBase > 10 &&
                (*cur)[0] >= 'A' && (*cur)[0] < radixEndChar1 )
        result = result * radixBase + ( (*cur)[0] - 'A' + 10 );

      else if ( radixBase > 10 &&
                (*cur)[0] >= 'a' && (*cur)[0] < radixEndChar2 )
        result = result * radixBase + ( (*cur)[0] - 'a' + 10 );

      else
        return result;

      (*cur)++;
    }

    return result;
  }


  static FT_Long
  t1_toint( FT_Byte**  cursor,
            FT_Byte*   limit )
  {