psobjs.c

QT 开发环境里面一个很重要的文件

/***************************************************************************/
/*                                                                         */
/*  psobjs.c                                                               */
/*                                                                         */
/*    Auxiliary functions for PostScript fonts (body).                     */
/*                                                                         */
/*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006 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 "psconv.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_PtrDist  delta  = 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  = FT_PAD_CEIL( new_size, 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                          *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/


  /* first character must be already part of the comment */

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


    while ( cur < limit )
    {
      if ( IS_PS_NEWLINE( *cur ) )
        break;
      cur++;
    }

    *acur = cur;
  }


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


    while ( cur < limit )
    {
      if ( !IS_PS_SPACE( *cur ) )
      {
        if ( *cur == '%' )
          /* According to the PLRM, a comment is equal to a space. */
          skip_comment( &cur, limit );
        else
          break;
      }
      cur++;
    }

    *acur = cur;
  }


  /* first character must be `(' */

  static void
  skip_literal_string( FT_Byte*  *acur,
                       FT_Byte*   limit )
  {
    FT_Byte*  cur   = *acur;
    FT_Int    embed = 0;


    while ( cur < limit )
    {
      if ( *cur == '\\' )
        cur++;
      else if ( *cur == '(' )
        embed++;
      else if ( *cur == ')' )
      {
        embed--;
        if ( embed == 0 )
        {
          cur++;
          break;
        }
      }
      cur++;
    }

    *acur = cur;
  }


  /* first character must be `<' */

  static void
  skip_string( PS_Parser  parser )
  {
    FT_Byte*  cur   = parser->cursor;
    FT_Byte*  limit = parser->limit;


    while ( ++cur < limit )
    {
      /* All whitespace characters are ignored. */
      skip_spaces( &cur, limit );
      if ( cur >= limit )
        break;

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

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

    parser->cursor = cur;
  }


  /***********************************************************************/
  /*                                                                     */
  /* 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;


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

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

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

    if ( *cur == '<' )                              /* <...> */
    {
      if ( cur + 1 < limit && *(cur + 1) == '<' )   /* << */
      {
        cur++;
        cur++;
        goto Exit;
      }
      parser->cursor = cur;
      skip_string( parser );
      return;
    }

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

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

    /* anything else */
    while ( cur < limit )
    {
      if ( *cur == ')' )
      {
        FT_ERROR(( "ps_parser_skip_PS_token: "
                   "unexpected closing delimiter `)'\n" ));
        parser->error = PSaux_Err_Invalid_File_Format;
        goto Exit;
      }
      else if ( IS_PS_DELIM( *cur ) )
        break;

      cur++;
    }

  Exit:
    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_Byte   starter, ender;
    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;