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-rw-r--r--modules/freetype2/src/cache/ftccmap.c323
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diff --git a/modules/freetype2/src/cache/ftccmap.c b/modules/freetype2/src/cache/ftccmap.c
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+/****************************************************************************
+ *
+ * ftccmap.c
+ *
+ * FreeType CharMap cache (body)
+ *
+ * Copyright (C) 2000-2023 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/freetype.h>
+#include <freetype/ftcache.h>
+#include "ftcmanag.h"
+#include <freetype/internal/ftmemory.h>
+#include <freetype/internal/ftobjs.h>
+#include <freetype/internal/ftdebug.h>
+
+#include "ftccback.h"
+#include "ftcerror.h"
+
+#undef FT_COMPONENT
+#define FT_COMPONENT cache
+
+
+ /**************************************************************************
+ *
+ * Each FTC_CMapNode contains a simple array to map a range of character
+ * codes to equivalent glyph indices.
+ *
+ * For now, the implementation is very basic: Each node maps a range of
+ * 128 consecutive character codes to their corresponding glyph indices.
+ *
+ * We could do more complex things, but I don't think it is really very
+ * useful.
+ *
+ */
+
+
+ /* number of glyph indices / character code per node */
+#define FTC_CMAP_INDICES_MAX 128
+
+ /* compute a query/node hash */
+#define FTC_CMAP_HASH( faceid, index, charcode ) \
+ ( FTC_FACE_ID_HASH( faceid ) + 211 * (index) + \
+ ( (charcode) / FTC_CMAP_INDICES_MAX ) )
+
+ /* the charmap query */
+ typedef struct FTC_CMapQueryRec_
+ {
+ FTC_FaceID face_id;
+ FT_UInt cmap_index;
+ FT_UInt32 char_code;
+
+ } FTC_CMapQueryRec, *FTC_CMapQuery;
+
+#define FTC_CMAP_QUERY( x ) ((FTC_CMapQuery)(x))
+
+ /* the cmap cache node */
+ typedef struct FTC_CMapNodeRec_
+ {
+ FTC_NodeRec node;
+ FTC_FaceID face_id;
+ FT_UInt cmap_index;
+ FT_UInt32 first; /* first character in node */
+ FT_UInt16 indices[FTC_CMAP_INDICES_MAX]; /* array of glyph indices */
+
+ } FTC_CMapNodeRec, *FTC_CMapNode;
+
+#define FTC_CMAP_NODE( x ) ( (FTC_CMapNode)( x ) )
+
+ /* if (indices[n] == FTC_CMAP_UNKNOWN), we assume that the corresponding */
+ /* glyph indices haven't been queried through FT_Get_Glyph_Index() yet */
+#define FTC_CMAP_UNKNOWN (FT_UInt16)~0
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /***** *****/
+ /***** CHARMAP NODES *****/
+ /***** *****/
+ /*************************************************************************/
+ /*************************************************************************/
+
+
+ FT_CALLBACK_DEF( void )
+ ftc_cmap_node_free( FTC_Node ftcnode,
+ FTC_Cache cache )
+ {
+ FTC_CMapNode node = (FTC_CMapNode)ftcnode;
+ FT_Memory memory = cache->memory;
+
+
+ FT_FREE( node );
+ }
+
+
+ /* initialize a new cmap node */
+ FT_CALLBACK_DEF( FT_Error )
+ ftc_cmap_node_new( FTC_Node *ftcanode,
+ FT_Pointer ftcquery,
+ FTC_Cache cache )
+ {
+ FTC_CMapNode *anode = (FTC_CMapNode*)ftcanode;
+ FTC_CMapQuery query = (FTC_CMapQuery)ftcquery;
+ FT_Error error;
+ FT_Memory memory = cache->memory;
+ FTC_CMapNode node = NULL;
+ FT_UInt nn;
+
+
+ if ( !FT_QNEW( node ) )
+ {
+ node->face_id = query->face_id;
+ node->cmap_index = query->cmap_index;
+ node->first = (query->char_code / FTC_CMAP_INDICES_MAX) *
+ FTC_CMAP_INDICES_MAX;
+
+ for ( nn = 0; nn < FTC_CMAP_INDICES_MAX; nn++ )
+ node->indices[nn] = FTC_CMAP_UNKNOWN;
+ }
+
+ *anode = node;
+ return error;
+ }
+
+
+ /* compute the weight of a given cmap node */
+ FT_CALLBACK_DEF( FT_Offset )
+ ftc_cmap_node_weight( FTC_Node cnode,
+ FTC_Cache cache )
+ {
+ FT_UNUSED( cnode );
+ FT_UNUSED( cache );
+
+ return sizeof ( *cnode );
+ }
+
+
+ /* compare a cmap node to a given query */
+ FT_CALLBACK_DEF( FT_Bool )
+ ftc_cmap_node_compare( FTC_Node ftcnode,
+ FT_Pointer ftcquery,
+ FTC_Cache cache,
+ FT_Bool* list_changed )
+ {
+ FTC_CMapNode node = (FTC_CMapNode)ftcnode;
+ FTC_CMapQuery query = (FTC_CMapQuery)ftcquery;
+ FT_UNUSED( cache );
+
+
+ if ( list_changed )
+ *list_changed = FALSE;
+ if ( node->face_id == query->face_id &&
+ node->cmap_index == query->cmap_index )
+ {
+ FT_UInt32 offset = (FT_UInt32)( query->char_code - node->first );
+
+
+ return FT_BOOL( offset < FTC_CMAP_INDICES_MAX );
+ }
+
+ return 0;
+ }
+
+
+ FT_CALLBACK_DEF( FT_Bool )
+ ftc_cmap_node_remove_faceid( FTC_Node ftcnode,
+ FT_Pointer ftcface_id,
+ FTC_Cache cache,
+ FT_Bool* list_changed )
+ {
+ FTC_CMapNode node = (FTC_CMapNode)ftcnode;
+ FTC_FaceID face_id = (FTC_FaceID)ftcface_id;
+ FT_UNUSED( cache );
+
+
+ if ( list_changed )
+ *list_changed = FALSE;
+ return FT_BOOL( node->face_id == face_id );
+ }
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /***** *****/
+ /***** GLYPH IMAGE CACHE *****/
+ /***** *****/
+ /*************************************************************************/
+ /*************************************************************************/
+
+
+ static
+ const FTC_CacheClassRec ftc_cmap_cache_class =
+ {
+ ftc_cmap_node_new, /* FTC_Node_NewFunc node_new */
+ ftc_cmap_node_weight, /* FTC_Node_WeightFunc node_weight */
+ ftc_cmap_node_compare, /* FTC_Node_CompareFunc node_compare */
+ ftc_cmap_node_remove_faceid, /* FTC_Node_CompareFunc node_remove_faceid */
+ ftc_cmap_node_free, /* FTC_Node_FreeFunc node_free */
+
+ sizeof ( FTC_CacheRec ),
+ ftc_cache_init, /* FTC_Cache_InitFunc cache_init */
+ ftc_cache_done, /* FTC_Cache_DoneFunc cache_done */
+ };
+
+
+ /* documentation is in ftcache.h */
+
+ FT_EXPORT_DEF( FT_Error )
+ FTC_CMapCache_New( FTC_Manager manager,
+ FTC_CMapCache *acache )
+ {
+ return FTC_Manager_RegisterCache( manager,
+ &ftc_cmap_cache_class,
+ FTC_CACHE_P( acache ) );
+ }
+
+
+ /* documentation is in ftcache.h */
+
+ FT_EXPORT_DEF( FT_UInt )
+ FTC_CMapCache_Lookup( FTC_CMapCache cmap_cache,
+ FTC_FaceID face_id,
+ FT_Int cmap_index,
+ FT_UInt32 char_code )
+ {
+ FTC_Cache cache = FTC_CACHE( cmap_cache );
+ FTC_CMapQueryRec query;
+ FTC_Node node;
+ FT_Error error;
+ FT_UInt gindex = 0;
+ FT_Offset hash;
+ FT_Int no_cmap_change = 0;
+
+
+ if ( cmap_index < 0 )
+ {
+ /* Treat a negative cmap index as a special value, meaning that you */
+ /* don't want to change the FT_Face's character map through this */
+ /* call. This can be useful if the face requester callback already */
+ /* sets the face's charmap to the appropriate value. */
+
+ no_cmap_change = 1;
+ cmap_index = 0;
+ }
+
+ if ( !cache )
+ {
+ FT_TRACE0(( "FTC_CMapCache_Lookup: bad arguments, returning 0\n" ));
+ return 0;
+ }
+
+ query.face_id = face_id;
+ query.cmap_index = (FT_UInt)cmap_index;
+ query.char_code = char_code;
+
+ hash = FTC_CMAP_HASH( face_id, (FT_UInt)cmap_index, char_code );
+
+#if 1
+ FTC_CACHE_LOOKUP_CMP( cache, ftc_cmap_node_compare, hash, &query,
+ node, error );
+#else
+ error = FTC_Cache_Lookup( cache, hash, &query, &node );
+#endif
+ if ( error )
+ goto Exit;
+
+ FT_ASSERT( char_code - FTC_CMAP_NODE( node )->first <
+ FTC_CMAP_INDICES_MAX );
+
+ /* something rotten can happen with rogue clients */
+ if ( char_code - FTC_CMAP_NODE( node )->first >= FTC_CMAP_INDICES_MAX )
+ return 0; /* XXX: should return appropriate error */
+
+ gindex = FTC_CMAP_NODE( node )->indices[char_code -
+ FTC_CMAP_NODE( node )->first];
+ if ( gindex == FTC_CMAP_UNKNOWN )
+ {
+ FT_Face face;
+
+
+ gindex = 0;
+
+ error = FTC_Manager_LookupFace( cache->manager,
+ FTC_CMAP_NODE( node )->face_id,
+ &face );
+ if ( error )
+ goto Exit;
+
+ if ( cmap_index < face->num_charmaps )
+ {
+ FT_CharMap old = face->charmap;
+ FT_CharMap cmap = face->charmaps[cmap_index];
+
+
+ if ( !no_cmap_change )
+ face->charmap = cmap;
+
+ gindex = FT_Get_Char_Index( face, char_code );
+
+ if ( !no_cmap_change )
+ face->charmap = old;
+ }
+
+ FTC_CMAP_NODE( node )->indices[char_code -
+ FTC_CMAP_NODE( node )->first]
+ = (FT_UShort)gindex;
+ }
+
+ Exit:
+ return gindex;
+ }
+
+
+/* END */
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