[wxWidgets.git] / src / freetype / sfnt / ttcmap.c

/***************************************************************************/
/*                                                                         */
/*  ttcmap.c                                                               */
/*                                                                         */
/*    TrueType character mapping table (cmap) support (body).              */
/*                                                                         */
/*  Copyright 1996-2000 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 <freetype/internal/ftdebug.h>
#include <freetype/internal/tterrors.h>


#ifdef FT_FLAT_COMPILE

#include "ttload.h"
#include "ttcmap.h"

#else

#include <sfnt/ttload.h>
#include <sfnt/ttcmap.h>

#endif


  /*************************************************************************/
  /*                                                                       */
  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  /* messages during execution.                                            */
  /*                                                                       */
#undef  FT_COMPONENT
#define FT_COMPONENT  trace_ttcmap


  static FT_UInt  code_to_index0( TT_CMapTable*  charmap,
                                  FT_ULong       char_code );
  static FT_UInt  code_to_index2( TT_CMapTable*  charmap,
                                  FT_ULong       char_code );
  static FT_UInt  code_to_index4( TT_CMapTable*  charmap,
                                  FT_ULong       char_code );
  static FT_UInt  code_to_index6( TT_CMapTable*  charmap,
                                  FT_ULong       char_code );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_CharMap_Load                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads a given TrueType character map into memory.                  */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: A handle to the parent face object.                      */
  /*    stream :: A handle to the current stream object.                   */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    table  :: A pointer to a cmap object.                              */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    The function assumes that the stream is already in use (i.e.,      */
  /*    opened).  In case of error, all partially allocated tables are     */
  /*    released.                                                          */
  /*                                                                       */
  LOCAL_FUNC
  FT_Error  TT_CharMap_Load( TT_Face        face,
                             TT_CMapTable*  cmap,
                             FT_Stream      stream )
  {
    FT_Error   error;
    FT_Memory  memory;
    FT_UShort  num_SH, num_Seg, i;

    FT_UShort  u, l;

    TT_CMap0*  cmap0;
    TT_CMap2*  cmap2;
    TT_CMap4*  cmap4;
    TT_CMap6*  cmap6;

    TT_CMap2SubHeader*  cmap2sub;
    TT_CMap4Segment*    segments;


    if ( cmap->loaded )
      return TT_Err_Ok;

    memory = stream->memory;

    if ( FILE_Seek( cmap->offset ) )
      return error;

    switch ( cmap->format )
    {
    case 0:
      cmap0 = &cmap->c.cmap0;

      if ( ALLOC( cmap0->glyphIdArray, 256L )            ||
           FILE_Read( cmap0->glyphIdArray, 256L ) )
         goto Fail;

      cmap->get_index = code_to_index0;
      break;

    case 2:
      num_SH = 0;
      cmap2  = &cmap->c.cmap2;

      /* allocate subheader keys */

      if ( ALLOC_ARRAY( cmap2->subHeaderKeys, 256, FT_UShort ) ||
           ACCESS_Frame( 512L )                                )
        goto Fail;

      for ( i = 0; i < 256; i++ )
      {
        u = GET_UShort() / 8;
        cmap2->subHeaderKeys[i] = u;

        if ( num_SH < u )
          num_SH = u;
      }

      FORGET_Frame();

      /* load subheaders */

      cmap2->numGlyphId = l =
        ( ( cmap->length - 2L * ( 256 + 3 ) - num_SH * 8L ) & 0xFFFF ) / 2;

      if ( ALLOC_ARRAY( cmap2->subHeaders,
                        num_SH + 1,
                        TT_CMap2SubHeader )    ||
           ACCESS_Frame( ( num_SH + 1 ) * 8L ) )
        goto Fail;

      cmap2sub = cmap2->subHeaders;

      for ( i = 0; i <= num_SH; i++ )
      {
        cmap2sub->firstCode     = GET_UShort();
        cmap2sub->entryCount    = GET_UShort();
        cmap2sub->idDelta       = GET_Short();
        /* we apply the location offset immediately */
        cmap2sub->idRangeOffset = GET_UShort() - ( num_SH - i ) * 8 - 2;

        cmap2sub++;
      }

      FORGET_Frame();

      /* load glyph IDs */

      if ( ALLOC_ARRAY( cmap2->glyphIdArray, l, FT_UShort ) ||
           ACCESS_Frame( l * 2L )                           )
        goto Fail;

      for ( i = 0; i < l; i++ )
        cmap2->glyphIdArray[i] = GET_UShort();

      FORGET_Frame();

      cmap->get_index = code_to_index2;
      break;

    case 4:
      cmap4 = &cmap->c.cmap4;

      /* load header */

      if ( ACCESS_Frame( 8L ) )
        goto Fail;

      cmap4->segCountX2    = GET_UShort();
      cmap4->searchRange   = GET_UShort();
      cmap4->entrySelector = GET_UShort();
      cmap4->rangeShift    = GET_UShort();

      num_Seg = cmap4->segCountX2 / 2;

      FORGET_Frame();

      /* load segments */

      if ( ALLOC_ARRAY( cmap4->segments,
                        num_Seg,
                        TT_CMap4Segment )           ||
           ACCESS_Frame( ( num_Seg * 4 + 1 ) * 2L ) )
        goto Fail;

      segments = cmap4->segments;

      for ( i = 0; i < num_Seg; i++ )
        segments[i].endCount      = GET_UShort();

      (void)GET_UShort();

      for ( i = 0; i < num_Seg; i++ )
        segments[i].startCount    = GET_UShort();

      for ( i = 0; i < num_Seg; i++ )
        segments[i].idDelta       = GET_Short();

      for ( i = 0; i < num_Seg; i++ )
        segments[i].idRangeOffset = GET_UShort();

      FORGET_Frame();

      cmap4->numGlyphId = l =
        ( ( cmap->length - ( 16L + 8L * num_Seg ) ) & 0xFFFF ) / 2;

      /* load IDs */

      if ( ALLOC_ARRAY( cmap4->glyphIdArray, l, FT_UShort ) ||
           ACCESS_Frame( l * 2L )                           )
        goto Fail;

      for ( i = 0; i < l; i++ )
        cmap4->glyphIdArray[i] = GET_UShort();

      FORGET_Frame();

      cmap->get_index = code_to_index4;

      cmap4->last_segment = cmap4->segments;
      break;

    case 6:
      cmap6 = &cmap->c.cmap6;

      if ( ACCESS_Frame( 4L ) )
        goto Fail;

      cmap6->firstCode  = GET_UShort();
      cmap6->entryCount = GET_UShort();

      FORGET_Frame();

      l = cmap6->entryCount;

      if ( ALLOC_ARRAY( cmap6->glyphIdArray,
                        cmap6->entryCount,
                        FT_Short )           ||
           ACCESS_Frame( l * 2L )            )
        goto Fail;

      for ( i = 0; i < l; i++ )
        cmap6->glyphIdArray[i] = GET_UShort();

      FORGET_Frame();
      cmap->get_index = code_to_index6;
      break;

    default:   /* corrupt character mapping table */
      return TT_Err_Invalid_CharMap_Format;

    }

    return TT_Err_Ok;

  Fail:
    TT_CharMap_Free( face, cmap );
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_CharMap_Free                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Destroys a character mapping table.                                */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face :: A handle to the parent face object.                        */
  /*    cmap :: A handle to a cmap object.                                 */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  LOCAL_FUNC
  FT_Error  TT_CharMap_Free( TT_Face        face,
                             TT_CMapTable*  cmap )
  {
    FT_Memory  memory;


    if ( !cmap )
      return TT_Err_Ok;

    memory = face->root.driver->root.memory;

    switch ( cmap->format )
    {
    case 0:
      FREE( cmap->c.cmap0.glyphIdArray );
      break;

    case 2:
      FREE( cmap->c.cmap2.subHeaderKeys );
      FREE( cmap->c.cmap2.subHeaders );
      FREE( cmap->c.cmap2.glyphIdArray );
      break;

    case 4:
      FREE( cmap->c.cmap4.segments );
      FREE( cmap->c.cmap4.glyphIdArray );
      cmap->c.cmap4.segCountX2 = 0;
      break;

    case 6:
      FREE( cmap->c.cmap6.glyphIdArray );
      cmap->c.cmap6.entryCount = 0;
      break;

    default:
      /* invalid table format, do nothing */
      ;
    }

    cmap->loaded = FALSE;
    return TT_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    code_to_index0                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Converts the character code into a glyph index.  Uses format 0.    */
  /*    `charCode' must be in the range 0x00-0xFF (otherwise 0 is          */
  /*    returned).                                                         */
  /*                                                                       */
  /* <Input>                                                               */
  /*    charCode :: The wanted character code.                             */
  /*    cmap0    :: A pointer to a cmap table in format 0.                 */
  /*                                                                       */
  /* <Return>                                                              */
  /*    Glyph index into the glyphs array.  0 if the glyph does not exist. */
  /*                                                                       */
  static
  FT_UInt  code_to_index0( TT_CMapTable*  cmap,
                           FT_ULong       charCode )
  {
    TT_CMap0*  cmap0 = &cmap->c.cmap0;


    return ( charCode <= 0xFF ? cmap0->glyphIdArray[charCode] : 0 );
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    code_to_index2                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Converts the character code into a glyph index.  Uses format 2.    */
  /*                                                                       */
  /* <Input>                                                               */
  /*    charCode :: The wanted character code.                             */
  /*    cmap2    :: A pointer to a cmap table in format 2.                 */
  /*                                                                       */
  /* <Return>                                                              */
  /*    Glyph index into the glyphs array.  0 if the glyph does not exist. */
  /*                                                                       */
  static
  FT_UInt  code_to_index2( TT_CMapTable*  cmap,
                           FT_ULong       charCode )
  {
    FT_UInt             result, index1, offset;
    FT_UInt             char_lo;
    FT_ULong            char_hi;
    TT_CMap2SubHeader*  sh2;
    TT_CMap2*           cmap2;


    cmap2   = &cmap->c.cmap2;
    result  = 0;
    char_lo = (FT_UInt)( charCode & 0xFF );
    char_hi = charCode >> 8;

    if ( char_hi == 0 )
    {
      /* an 8-bit character code -- we use the subHeader 0 in this case */
      /* to test whether the character code is in the charmap           */
      if ( cmap2->subHeaderKeys[char_lo] == 0 )
        result = cmap2->glyphIdArray[char_lo];
    }
    else
    {
      /* a 16-bit character code */
      index1 = cmap2->subHeaderKeys[char_hi & 0xFF];
      if ( index1 )
      {
        sh2      = cmap2->subHeaders + index1;
        char_lo -= sh2->firstCode;

        if ( char_lo < sh2->entryCount )
        {
          offset = sh2->idRangeOffset / 2 + char_lo;
          if ( offset < cmap2->numGlyphId )
          {
            result = cmap2->glyphIdArray[offset];
            if ( result )
              result = ( result + sh2->idDelta ) & 0xFFFF;
          }
        }
      }
    }

    return result;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    code_to_index4                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Converts the character code into a glyph index.  Uses format 4.    */
  /*                                                                       */
  /* <Input>                                                               */
  /*    charCode :: The wanted character code.                             */
  /*    cmap4    :: A pointer to a cmap table in format 4.                 */
  /*                                                                       */
  /* <Return>                                                              */
  /*    Glyph index into the glyphs array.  0 if the glyph does not exist. */
  /*                                                                       */
  static
  FT_UInt  code_to_index4( TT_CMapTable*  cmap,
                           FT_ULong       charCode )
  {
    FT_UInt          result, index1, segCount;
    TT_CMap4*        cmap4;
    TT_CMap4Segment  *seg4, *limit;


    cmap4    = &cmap->c.cmap4;
    result   = 0;
    segCount = cmap4->segCountX2 / 2;
    seg4     = cmap4->segments;
    limit    = seg4 + segCount;

    /* check against the last segment */
    seg4 = cmap4->last_segment;

    /* the following is equivalent to performing two tests, as in         */
    /*                                                                    */
    /*  if ( charCode >= seg4->startCount && charCode <= seg4->endCount ) */
    /*                                                                    */
    /* Yes, that's a bit strange, but it's faster, and the idea behind    */
    /* the cache is to significantly speed up charcode to glyph index     */
    /* conversion.                                                        */

    if ( (FT_ULong)(charCode       - seg4->startCount) <
         (FT_ULong)(seg4->endCount - seg4->startCount) )
      goto Found;

    for ( seg4 = cmap4->segments; seg4 < limit; seg4++ )
    {
      /* the ranges are sorted in increasing order.  If we are out of */
      /* the range here, the char code isn't in the charmap, so exit. */

      if ( charCode > seg4->endCount )
        continue;

      if ( charCode >= seg4->startCount )
        goto Found;
    }
    return 0;

 Found:
    cmap4->last_segment = seg4;

    /* if the idRangeOffset is 0, we can compute the glyph index */
    /* directly                                                  */

    if ( seg4->idRangeOffset == 0 )
      result = ( charCode + seg4->idDelta ) & 0xFFFF;
    else
    {
      /* otherwise, we must use the glyphIdArray to do it */
      index1 = seg4->idRangeOffset / 2
               + ( charCode - seg4->startCount )
               + ( seg4 - cmap4->segments )
               - segCount;

      if ( index1 < cmap4->numGlyphId       &&
           cmap4->glyphIdArray[index1] != 0 )
        result = ( cmap4->glyphIdArray[index1] + seg4->idDelta ) & 0xFFFF;
    }

    return result;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    code_to_index6                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Converts the character code into a glyph index.  Uses format 6.    */
  /*                                                                       */
  /* <Input>                                                               */
  /*    charCode :: The wanted character code.                             */
  /*    cmap6    :: A pointer to a cmap table in format 6.                 */
  /*                                                                       */
  /* <Return>                                                              */
  /*    Glyph index into the glyphs array.  0 if the glyph does not exist. */
  /*                                                                       */
  static
  FT_UInt  code_to_index6( TT_CMapTable*  cmap,
                           FT_ULong       charCode )
  {
    TT_CMap6*  cmap6;
    FT_UInt    result = 0;


    cmap6     = &cmap->c.cmap6;
    result    = 0;
    charCode -= cmap6->firstCode;

    if ( charCode < cmap6->entryCount )
      result =  cmap6->glyphIdArray[charCode];

    return result;
  }


/* END */
Commit	Line	Data
cabec872 RR	1	/***************************************************************************/
	2	/* */
	3	/* ttcmap.c */
	4	/* */
	5	/* TrueType character mapping table (cmap) support (body). */
	6	/* */
	7	/* Copyright 1996-2000 by */
	8	/* David Turner, Robert Wilhelm, and Werner Lemberg. */
	9	/* */
	10	/* This file is part of the FreeType project, and may only be used, */
	11	/* modified, and distributed under the terms of the FreeType project */
	12	/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
	13	/* this file you indicate that you have read the license and */
	14	/* understand and accept it fully. */
	15	/* */
	16	/***************************************************************************/
	17
	18
	19	#include <freetype/internal/ftdebug.h>
	20	#include <freetype/internal/tterrors.h>
	21
	22
	23	#ifdef FT_FLAT_COMPILE
	24
	25	#include "ttload.h"
	26	#include "ttcmap.h"
	27
	28	#else
	29
	30	#include <sfnt/ttload.h>
	31	#include <sfnt/ttcmap.h>
	32
	33	#endif
	34
	35
	36	/*************************************************************************/
	37	/* */
	38	/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
	39	/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
	40	/* messages during execution. */
	41	/* */
	42	#undef FT_COMPONENT
	43	#define FT_COMPONENT trace_ttcmap
	44
	45
	46	static FT_UInt code_to_index0( TT_CMapTable* charmap,
	47	FT_ULong char_code );
	48	static FT_UInt code_to_index2( TT_CMapTable* charmap,
	49	FT_ULong char_code );
	50	static FT_UInt code_to_index4( TT_CMapTable* charmap,
	51	FT_ULong char_code );
	52	static FT_UInt code_to_index6( TT_CMapTable* charmap,
	53	FT_ULong char_code );
	54
	55
	56	/*************************************************************************/
	57	/* */
	58	/* <Function> */
	59	/* TT_CharMap_Load */
	60	/* */
	61	/* <Description> */
	62	/* Loads a given TrueType character map into memory. */
	63	/* */
	64	/* <Input> */
65	/* face :: A handle to the parent face object. */
66	/* stream :: A handle to the current stream object. */
67	/* */
68	/* <InOut> */
69	/* table :: A pointer to a cmap object. */
70	/* */
71	/* <Return> */
72	/* FreeType error code. 0 means success. */
73	/* */
74	/* <Note> */
75	/* The function assumes that the stream is already in use (i.e., */
76	/* opened). In case of error, all partially allocated tables are */
77	/* released. */
78	/* */
79	LOCAL_FUNC
80	FT_Error TT_CharMap_Load( TT_Face face,
81	TT_CMapTable* cmap,
82	FT_Stream stream )
83	{
84	FT_Error error;
85	FT_Memory memory;
86	FT_UShort num_SH, num_Seg, i;
87
88	FT_UShort u, l;
89
90	TT_CMap0* cmap0;
91	TT_CMap2* cmap2;
92	TT_CMap4* cmap4;
93	TT_CMap6* cmap6;
94
95	TT_CMap2SubHeader* cmap2sub;
96	TT_CMap4Segment* segments;
97
98
99	if ( cmap->loaded )
100	return TT_Err_Ok;
101
102	memory = stream->memory;
103
104	if ( FILE_Seek( cmap->offset ) )
105	return error;
106
107	switch ( cmap->format )
108	{
109	case 0:
110	cmap0 = &cmap->c.cmap0;
111
112	if ( ALLOC( cmap0->glyphIdArray, 256L ) \|\|
113	FILE_Read( cmap0->glyphIdArray, 256L ) )
114	goto Fail;
115
116	cmap->get_index = code_to_index0;
117	break;
118
119	case 2:
120	num_SH = 0;
121	cmap2 = &cmap->c.cmap2;
122
123	/* allocate subheader keys */
124
125	if ( ALLOC_ARRAY( cmap2->subHeaderKeys, 256, FT_UShort ) \|\|
126	ACCESS_Frame( 512L ) )
127	goto Fail;
128
129	for ( i = 0; i < 256; i++ )
130	{
131	u = GET_UShort() / 8;
132	cmap2->subHeaderKeys[i] = u;
133
134	if ( num_SH < u )
135	num_SH = u;
136	}
137
138	FORGET_Frame();
139
140	/* load subheaders */
141
142	cmap2->numGlyphId = l =
143	( ( cmap->length - 2L * ( 256 + 3 ) - num_SH * 8L ) & 0xFFFF ) / 2;
144
145	if ( ALLOC_ARRAY( cmap2->subHeaders,
146	num_SH + 1,
147	TT_CMap2SubHeader ) \|\|
148	ACCESS_Frame( ( num_SH + 1 ) * 8L ) )
149	goto Fail;
150
151	cmap2sub = cmap2->subHeaders;
152
153	for ( i = 0; i <= num_SH; i++ )
154	{
155	cmap2sub->firstCode = GET_UShort();
156	cmap2sub->entryCount = GET_UShort();
157	cmap2sub->idDelta = GET_Short();
158	/* we apply the location offset immediately */
159	cmap2sub->idRangeOffset = GET_UShort() - ( num_SH - i ) * 8 - 2;
160
161	cmap2sub++;
162	}
163
164	FORGET_Frame();
165
166	/* load glyph IDs */
167
168	if ( ALLOC_ARRAY( cmap2->glyphIdArray, l, FT_UShort ) \|\|
169	ACCESS_Frame( l * 2L ) )
170	goto Fail;
171
172	for ( i = 0; i < l; i++ )
173	cmap2->glyphIdArray[i] = GET_UShort();
174
175	FORGET_Frame();
176
177	cmap->get_index = code_to_index2;
178	break;
179
180	case 4:
181	cmap4 = &cmap->c.cmap4;
182
183	/* load header */
184
185	if ( ACCESS_Frame( 8L ) )
186	goto Fail;
187
188	cmap4->segCountX2 = GET_UShort();
189	cmap4->searchRange = GET_UShort();
190	cmap4->entrySelector = GET_UShort();
191	cmap4->rangeShift = GET_UShort();
192
193	num_Seg = cmap4->segCountX2 / 2;
194
195	FORGET_Frame();
196
197	/* load segments */
198
199	if ( ALLOC_ARRAY( cmap4->segments,
200	num_Seg,
201	TT_CMap4Segment ) \|\|
202	ACCESS_Frame( ( num_Seg * 4 + 1 ) * 2L ) )
203	goto Fail;
204
205	segments = cmap4->segments;
206
207	for ( i = 0; i < num_Seg; i++ )
208	segments[i].endCount = GET_UShort();
209
210	(void)GET_UShort();
211
212	for ( i = 0; i < num_Seg; i++ )
213	segments[i].startCount = GET_UShort();
214
215	for ( i = 0; i < num_Seg; i++ )
216	segments[i].idDelta = GET_Short();
217
218	for ( i = 0; i < num_Seg; i++ )
219	segments[i].idRangeOffset = GET_UShort();
220
221	FORGET_Frame();
222
223	cmap4->numGlyphId = l =
224	( ( cmap->length - ( 16L + 8L * num_Seg ) ) & 0xFFFF ) / 2;
225
226	/* load IDs */
227
228	if ( ALLOC_ARRAY( cmap4->glyphIdArray, l, FT_UShort ) \|\|
229	ACCESS_Frame( l * 2L ) )
230	goto Fail;
231
232	for ( i = 0; i < l; i++ )
233	cmap4->glyphIdArray[i] = GET_UShort();
234
235	FORGET_Frame();
236
237	cmap->get_index = code_to_index4;
238
239	cmap4->last_segment = cmap4->segments;
240	break;
241
242	case 6:
243	cmap6 = &cmap->c.cmap6;
244
245	if ( ACCESS_Frame( 4L ) )
246	goto Fail;
247
248	cmap6->firstCode = GET_UShort();
249	cmap6->entryCount = GET_UShort();
250
251	FORGET_Frame();
252
253	l = cmap6->entryCount;
254
255	if ( ALLOC_ARRAY( cmap6->glyphIdArray,
256	cmap6->entryCount,
257	FT_Short ) \|\|
258	ACCESS_Frame( l * 2L ) )
259	goto Fail;
260
261	for ( i = 0; i < l; i++ )
262	cmap6->glyphIdArray[i] = GET_UShort();
263
264	FORGET_Frame();
265	cmap->get_index = code_to_index6;
266	break;
267
268	default: /* corrupt character mapping table */
269	return TT_Err_Invalid_CharMap_Format;
270
271	}
272
273	return TT_Err_Ok;
274
275	Fail:
276	TT_CharMap_Free( face, cmap );
277	return error;
278	}
279
280
281	/*************************************************************************/
282	/* */
283	/* <Function> */
284	/* TT_CharMap_Free */
285	/* */
286	/* <Description> */
287	/* Destroys a character mapping table. */
288	/* */
289	/* <Input> */
290	/* face :: A handle to the parent face object. */
291	/* cmap :: A handle to a cmap object. */
292	/* */
293	/* <Return> */
294	/* FreeType error code. 0 means success. */
295	/* */
296	LOCAL_FUNC
297	FT_Error TT_CharMap_Free( TT_Face face,
298	TT_CMapTable* cmap )
299	{
300	FT_Memory memory;
301
302
303	if ( !cmap )
304	return TT_Err_Ok;
305
306	memory = face->root.driver->root.memory;
307
308	switch ( cmap->format )
309	{
310	case 0:
311	FREE( cmap->c.cmap0.glyphIdArray );
312	break;
313
314	case 2:
315	FREE( cmap->c.cmap2.subHeaderKeys );
316	FREE( cmap->c.cmap2.subHeaders );
317	FREE( cmap->c.cmap2.glyphIdArray );
318	break;
319
320	case 4:
321	FREE( cmap->c.cmap4.segments );
322	FREE( cmap->c.cmap4.glyphIdArray );
323	cmap->c.cmap4.segCountX2 = 0;
324	break;
325
326	case 6:
327	FREE( cmap->c.cmap6.glyphIdArray );
328	cmap->c.cmap6.entryCount = 0;
329	break;
330
331	default:
332	/* invalid table format, do nothing */
333	;
334	}
335
336	cmap->loaded = FALSE;
337	return TT_Err_Ok;
338	}
339
340
341	/*************************************************************************/
342	/* */
343	/* <Function> */
344	/* code_to_index0 */
345	/* */
346	/* <Description> */
347	/* Converts the character code into a glyph index. Uses format 0. */
348	/* `charCode' must be in the range 0x00-0xFF (otherwise 0 is */
349	/* returned). */
350	/* */
351	/* <Input> */
352	/* charCode :: The wanted character code. */
353	/* cmap0 :: A pointer to a cmap table in format 0. */
354	/* */
355	/* <Return> */
356	/* Glyph index into the glyphs array. 0 if the glyph does not exist. */
357	/* */
358	static
359	FT_UInt code_to_index0( TT_CMapTable* cmap,
360	FT_ULong charCode )
361	{
362	TT_CMap0* cmap0 = &cmap->c.cmap0;
363
364
365	return ( charCode <= 0xFF ? cmap0->glyphIdArray[charCode] : 0 );
366	}
367
368
369	/*************************************************************************/
370	/* */
371	/* <Function> */
372	/* code_to_index2 */
373	/* */
374	/* <Description> */
375	/* Converts the character code into a glyph index. Uses format 2. */
376	/* */
377	/* <Input> */
378	/* charCode :: The wanted character code. */
379	/* cmap2 :: A pointer to a cmap table in format 2. */
380	/* */
381	/* <Return> */
382	/* Glyph index into the glyphs array. 0 if the glyph does not exist. */
383	/* */
384	static
385	FT_UInt code_to_index2( TT_CMapTable* cmap,
386	FT_ULong charCode )
387	{
388	FT_UInt result, index1, offset;
389	FT_UInt char_lo;
390	FT_ULong char_hi;
391	TT_CMap2SubHeader* sh2;
392	TT_CMap2* cmap2;
393
394
395	cmap2 = &cmap->c.cmap2;
396	result = 0;
397	char_lo = (FT_UInt)( charCode & 0xFF );
398	char_hi = charCode >> 8;
399
400	if ( char_hi == 0 )
401	{
402	/* an 8-bit character code -- we use the subHeader 0 in this case */
403	/* to test whether the character code is in the charmap */
404	if ( cmap2->subHeaderKeys[char_lo] == 0 )
405	result = cmap2->glyphIdArray[char_lo];
406	}
407	else
408	{
409	/* a 16-bit character code */
410	index1 = cmap2->subHeaderKeys[char_hi & 0xFF];
411	if ( index1 )
412	{
413	sh2 = cmap2->subHeaders + index1;
414	char_lo -= sh2->firstCode;
415
416	if ( char_lo < sh2->entryCount )
417	{
418	offset = sh2->idRangeOffset / 2 + char_lo;
419	if ( offset < cmap2->numGlyphId )
420	{
421	result = cmap2->glyphIdArray[offset];
422	if ( result )
423	result = ( result + sh2->idDelta ) & 0xFFFF;
424	}
425	}
426	}
427	}
428
429	return result;
430	}
431
432
433	/*************************************************************************/
434	/* */
435	/* <Function> */
436	/* code_to_index4 */
437	/* */
438	/* <Description> */
439	/* Converts the character code into a glyph index. Uses format 4. */
440	/* */
441	/* <Input> */
442	/* charCode :: The wanted character code. */
443	/* cmap4 :: A pointer to a cmap table in format 4. */
444	/* */
445	/* <Return> */
446	/* Glyph index into the glyphs array. 0 if the glyph does not exist. */
447	/* */
448	static
449	FT_UInt code_to_index4( TT_CMapTable* cmap,
450	FT_ULong charCode )
451	{
452	FT_UInt result, index1, segCount;
453	TT_CMap4* cmap4;
454	TT_CMap4Segment seg4, limit;
455
456
457	cmap4 = &cmap->c.cmap4;
458	result = 0;
459	segCount = cmap4->segCountX2 / 2;
460	seg4 = cmap4->segments;
461	limit = seg4 + segCount;
462
463	/* check against the last segment */
464	seg4 = cmap4->last_segment;
465
466	/* the following is equivalent to performing two tests, as in */
467	/* */
468	/* if ( charCode >= seg4->startCount && charCode <= seg4->endCount ) */
469	/* */
470	/* Yes, that's a bit strange, but it's faster, and the idea behind */
471	/* the cache is to significantly speed up charcode to glyph index */
472	/* conversion. */
473
474	if ( (FT_ULong)(charCode - seg4->startCount) <
475	(FT_ULong)(seg4->endCount - seg4->startCount) )
476	goto Found;
477
478	for ( seg4 = cmap4->segments; seg4 < limit; seg4++ )
479	{
480	/* the ranges are sorted in increasing order. If we are out of */
481	/* the range here, the char code isn't in the charmap, so exit. */
482
483	if ( charCode > seg4->endCount )
484	continue;
485
486	if ( charCode >= seg4->startCount )
487	goto Found;
488	}
489	return 0;
490
491	Found:
492	cmap4->last_segment = seg4;
493
494	/* if the idRangeOffset is 0, we can compute the glyph index */
495	/* directly */
496
497	if ( seg4->idRangeOffset == 0 )
498	result = ( charCode + seg4->idDelta ) & 0xFFFF;
499	else
500	{
501	/* otherwise, we must use the glyphIdArray to do it */
502	index1 = seg4->idRangeOffset / 2
503	+ ( charCode - seg4->startCount )
504	+ ( seg4 - cmap4->segments )
505	- segCount;
506
507	if ( index1 < cmap4->numGlyphId &&
508	cmap4->glyphIdArray[index1] != 0 )
509	result = ( cmap4->glyphIdArray[index1] + seg4->idDelta ) & 0xFFFF;
510	}
511
512	return result;
513	}
514
515
516	/*************************************************************************/
517	/* */
518	/* <Function> */
519	/* code_to_index6 */
520	/* */
521	/* <Description> */
522	/* Converts the character code into a glyph index. Uses format 6. */
523	/* */
524	/* <Input> */
525	/* charCode :: The wanted character code. */
526	/* cmap6 :: A pointer to a cmap table in format 6. */
527	/* */
528	/* <Return> */
529	/* Glyph index into the glyphs array. 0 if the glyph does not exist. */
530	/* */
531	static
532	FT_UInt code_to_index6( TT_CMapTable* cmap,
533	FT_ULong charCode )
534	{
535	TT_CMap6* cmap6;
536	FT_UInt result = 0;
537
538
539	cmap6 = &cmap->c.cmap6;
540	result = 0;
541	charCode -= cmap6->firstCode;
542
543	if ( charCode < cmap6->entryCount )
544	result = cmap6->glyphIdArray[charCode];
545
546	return result;
547	}
548
549
550	/* END */