Edit
kc3-lang/freetype/src/cache/ftccmap.c
Werner Lemberg
- src/cache/ftccmap.c
-
/***************************************************************************/ /* */ /* ftccmap.c */ /* */ /* FreeType CharMap cache (body) */ /* */ /* Copyright 2000-2001, 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_FREETYPE_H #include FT_CACHE_H #include "ftcmanag.h" #include FT_INTERNAL_MEMORY_H #include FT_INTERNAL_DEBUG_H #include FT_TRUETYPE_IDS_H #include "ftccback.h" #include "ftcerror.h" #undef FT_COMPONENT #define FT_COMPONENT trace_cache #ifdef FT_CONFIG_OPTION_OLD_INTERNALS typedef enum FTC_OldCMapType_ { FTC_OLD_CMAP_BY_INDEX = 0, FTC_OLD_CMAP_BY_ENCODING = 1, FTC_OLD_CMAP_BY_ID = 2 } FTC_OldCMapType; typedef struct FTC_OldCMapIdRec_ { FT_UInt platform; FT_UInt encoding; } FTC_OldCMapIdRec, *FTC_OldCMapId; typedef struct FTC_OldCMapDescRec_ { FTC_FaceID face_id; FTC_OldCMapType type; union { FT_UInt index; FT_Encoding encoding; FTC_OldCMapIdRec id; } u; } FTC_OldCMapDescRec, *FTC_OldCMapDesc; #endif /* FT_CONFIG_OLD_INTERNALS */ /*************************************************************************/ /* */ /* 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 ) + \ ( (char_code) / 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)) #define FTC_CMAP_QUERY_HASH( x ) \ FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->char_code ) /* 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 ) ) #define FTC_CMAP_NODE_HASH( x ) \ FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->first ) /* 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)-1 ) /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** 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; FT_UInt nn; if ( !FT_NEW( 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_ULong ) 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 ) { FTC_CMapNode node = (FTC_CMapNode)ftcnode; FTC_CMapQuery query = (FTC_CMapQuery)ftcquery; FT_UNUSED( cache ); 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 ) { FTC_CMapNode node = (FTC_CMapNode)ftcnode; FTC_FaceID face_id = (FTC_FaceID)ftcface_id; FT_UNUSED( cache ); return FT_BOOL( node->face_id == face_id ); } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** GLYPH IMAGE CACHE *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ FT_CALLBACK_TABLE_DEF const FTC_CacheClassRec ftc_cmap_cache_class = { ftc_cmap_node_new, ftc_cmap_node_weight, ftc_cmap_node_compare, ftc_cmap_node_remove_faceid, ftc_cmap_node_free, sizeof ( FTC_CacheRec ), ftc_cache_init, ftc_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 ) ); } #ifdef FT_CONFIG_OPTION_OLD_INTERNALS /* * Unfortunately, it is not possible to support binary backwards * compatibility in the cmap cache. The FTC_CMapCache_Lookup signature * changes were too deep, and there is no clever hackish way to detect * what kind of structure we are being passed. * * On the other hand it seems that no production code is using this * function on Unix distributions. */ #endif /* 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_CMapNode node; FT_Error error; FT_UInt gindex = 0; FT_UInt32 hash; if ( !cache ) { FT_ERROR(( "FTC_CMapCache_Lookup: bad arguments, returning 0!\n" )); return 0; } #ifdef FT_CONFIG_OPTION_OLD_INTERNALS /* * Detect a call from a rogue client that thinks it is linking * to FreeType 2.1.7. This is possible because the third parameter * is then a character code, and we have never seen any font with * more than a few charmaps, so if the index is very large... * * It is also very unlikely that a rogue client is interested * in Unicode values 0 to 15. * * NOTE: The original threshold was 4, but we found a font from the * Adobe Acrobat Reader Pack, named `KozMinProVI-Regular.otf', * which contains more than 5 charmaps. */ if ( cmap_index >= 16 ) { FTC_OldCMapDesc desc = (FTC_OldCMapDesc) face_id; char_code = (FT_UInt32)cmap_index; query.face_id = desc->face_id; switch ( desc->type ) { case FTC_OLD_CMAP_BY_INDEX: query.cmap_index = desc->u.index; query.char_code = (FT_UInt32)cmap_index; break; case FTC_OLD_CMAP_BY_ENCODING: { FT_Face face; error = FTC_Manager_LookupFace( cache->manager, desc->face_id, &face ); if ( error ) return 0; FT_Select_Charmap( face, desc->u.encoding ); return FT_Get_Char_Index( face, char_code ); } break; default: return 0; } } else #endif /* FT_CONFIG_OPTION_OLD_INTERNALS */ { query.face_id = face_id; query.cmap_index = (FT_UInt)cmap_index; query.char_code = char_code; } hash = FTC_CMAP_HASH( face_id, 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, (FTC_Node*) &node ); #endif if ( error ) goto Exit; FT_ASSERT( (FT_UInt)( char_code - node->first ) < FTC_CMAP_INDICES_MAX ); /* something rotten can happen with rogue clients */ if ( (FT_UInt)( char_code - node->first >= FTC_CMAP_INDICES_MAX ) ) return 0; gindex = node->indices[char_code - node->first]; if ( gindex == FTC_CMAP_UNKNOWN ) { FT_Face face; gindex = 0; error = FTC_Manager_LookupFace( cache->manager, node->face_id, &face ); if ( error ) goto Exit; if ( (FT_UInt)cmap_index < (FT_UInt)face->num_charmaps ) { FT_CharMap old, cmap = NULL; old = face->charmap; cmap = face->charmaps[cmap_index]; if ( old != cmap ) FT_Set_Charmap( face, cmap ); gindex = FT_Get_Char_Index( face, char_code ); if ( old != cmap ) FT_Set_Charmap( face, old ); } node->indices[char_code - node->first] = (FT_UShort)gindex; } Exit: return gindex; } /* END */