1 /***************************************************************************/
5 /* The FreeType services (specification only). */
7 /* Copyright 2003, 2004, 2005 by */
8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */
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. */
16 /***************************************************************************/
18 /*************************************************************************/
20 /* Each module can export one or more `services'. Each service is */
21 /* identified by a constant string and modeled by a pointer; the latter */
22 /* generally corresponds to a structure containing function pointers. */
24 /* Note that a service's data cannot be a mere function pointer because */
25 /* in C it is possible that function pointers might be implemented */
26 /* differently than data pointers (e.g. 48 bits instead of 32). */
28 /*************************************************************************/
37 #if defined( _MSC_VER ) /* Visual C++ (and Intel C++) */
39 /* we disable the warning `conditional expression is constant' here */
40 /* in order to compile cleanly with the maximum level of warnings */
41 #pragma warning( disable : 4127 )
47 * FT_FACE_FIND_SERVICE
50 * This macro is used to look up a service from a face's driver module.
54 * The source face handle.
57 * A string describing the service as defined in the service's
58 * header files (e.g. FT_SERVICE_ID_MULTI_MASTERS which expands to
59 * `multi-masters'). It is automatically prefixed with
64 * A variable that receives the service pointer. Will be NULL
69 #define FT_FACE_FIND_SERVICE( face, ptr, id ) \
71 FT_Module module = FT_MODULE( FT_FACE( face )->driver ); \
72 FT_Pointer _tmp_ = NULL; \
73 FT_Pointer* _pptr_ = (FT_Pointer*)&(ptr); \
76 if ( module->clazz->get_interface ) \
77 _tmp_ = module->clazz->get_interface( module, FT_SERVICE_ID_ ## id ); \
83 #define FT_FACE_FIND_SERVICE( face, ptr, id ) \
85 FT_Module module = FT_MODULE( FT_FACE( face )->driver ); \
86 FT_Pointer _tmp_ = NULL; \
88 if ( module->clazz->get_interface ) \
89 _tmp_ = module->clazz->get_interface( module, FT_SERVICE_ID_ ## id ); \
97 * FT_FACE_FIND_GLOBAL_SERVICE
100 * This macro is used to look up a service from all modules.
104 * The source face handle.
107 * A string describing the service as defined in the service's
108 * header files (e.g. FT_SERVICE_ID_MULTI_MASTERS which expands to
109 * `multi-masters'). It is automatically prefixed with
114 * A variable that receives the service pointer. Will be NULL
119 #define FT_FACE_FIND_GLOBAL_SERVICE( face, ptr, id ) \
121 FT_Module module = FT_MODULE( FT_FACE( face )->driver ); \
123 FT_Pointer* _pptr_ = (FT_Pointer*)&(ptr); \
126 _tmp_ = ft_module_get_service( module, FT_SERVICE_ID_ ## id ); \
132 #define FT_FACE_FIND_GLOBAL_SERVICE( face, ptr, id ) \
134 FT_Module module = FT_MODULE( FT_FACE( face )->driver ); \
138 _tmp_ = ft_module_get_service( module, FT_SERVICE_ID_ ## id ); \
145 /*************************************************************************/
146 /*************************************************************************/
148 /***** S E R V I C E D E S C R I P T O R S *****/
150 /*************************************************************************/
151 /*************************************************************************/
154 * The following structure is used to _describe_ a given service
155 * to the library. This is useful to build simple static service lists.
157 typedef struct FT_ServiceDescRec_
159 const char* serv_id; /* service name */
160 const void* serv_data; /* service pointer/data */
164 typedef const FT_ServiceDescRec* FT_ServiceDesc;
168 * Parse a list of FT_ServiceDescRec descriptors and look for
169 * a specific service by ID. Note that the last element in the
170 * array must be { NULL, NULL }, and that the function should
171 * return NULL if the service isn't available.
173 * This function can be used by modules to implement their
174 * `get_service' method.
176 FT_BASE( FT_Pointer )
177 ft_service_list_lookup( FT_ServiceDesc service_descriptors,
178 const char* service_id );
181 /*************************************************************************/
182 /*************************************************************************/
184 /***** S E R V I C E S C A C H E *****/
186 /*************************************************************************/
187 /*************************************************************************/
190 * This structure is used to store a cache for several frequently used
191 * services. It is the type of `face->internal->services'. You
192 * should only use FT_FACE_LOOKUP_SERVICE to access it.
194 * All fields should have the type FT_Pointer to relax compilation
195 * dependencies. We assume the developer isn't completely stupid.
197 * Each field must be named `service_XXXX' where `XXX' corresponds to
198 * the correct FT_SERVICE_ID_XXXX macro. See the definition of
199 * FT_FACE_LOOKUP_SERVICE below how this is implemented.
202 typedef struct FT_ServiceCacheRec_
204 FT_Pointer service_POSTSCRIPT_FONT_NAME;
205 FT_Pointer service_MULTI_MASTERS;
206 FT_Pointer service_GLYPH_DICT;
207 FT_Pointer service_PFR_METRICS;
208 FT_Pointer service_WINFNT;
210 } FT_ServiceCacheRec, *FT_ServiceCache;
214 * A magic number used within the services cache.
216 #define FT_SERVICE_UNAVAILABLE ((FT_Pointer)-2) /* magic number */
221 * FT_FACE_LOOKUP_SERVICE
224 * This macro is used to lookup a service from a face's driver module
229 * The source face handle containing the cache.
232 * The field name in the cache.
239 * A variable receiving the service data. NULL if not available.
243 #define FT_FACE_LOOKUP_SERVICE( face, ptr, id ) \
246 FT_Pointer* Pptr = (FT_Pointer*)&(ptr); \
249 svc = FT_FACE( face )->internal->services. service_ ## id; \
250 if ( svc == FT_SERVICE_UNAVAILABLE ) \
252 else if ( svc == NULL ) \
254 FT_FACE_FIND_SERVICE( face, svc, id ); \
256 FT_FACE( face )->internal->services. service_ ## id = \
257 (FT_Pointer)( svc != NULL ? svc \
258 : FT_SERVICE_UNAVAILABLE ); \
265 #define FT_FACE_LOOKUP_SERVICE( face, ptr, id ) \
270 svc = FT_FACE( face )->internal->services. service_ ## id; \
271 if ( svc == FT_SERVICE_UNAVAILABLE ) \
273 else if ( svc == NULL ) \
275 FT_FACE_FIND_SERVICE( face, svc, id ); \
277 FT_FACE( face )->internal->services. service_ ## id = \
278 (FT_Pointer)( svc != NULL ? svc \
279 : FT_SERVICE_UNAVAILABLE ); \
287 * A macro used to define new service structure types.
290 #define FT_DEFINE_SERVICE( name ) \
291 typedef struct FT_Service_ ## name ## Rec_ \
292 FT_Service_ ## name ## Rec ; \
293 typedef struct FT_Service_ ## name ## Rec_ \
294 const * FT_Service_ ## name ; \
295 struct FT_Service_ ## name ## Rec_
300 * The header files containing the services.
303 #define FT_SERVICE_BDF_H <freetype/internal/services/svbdf.h>
304 #define FT_SERVICE_GLYPH_DICT_H <freetype/internal/services/svgldict.h>
305 #define FT_SERVICE_MULTIPLE_MASTERS_H <freetype/internal/services/svmm.h>
306 #define FT_SERVICE_OPENTYPE_VALIDATE_H <freetype/internal/services/svotval.h>
307 #define FT_SERVICE_PFR_H <freetype/internal/services/svpfr.h>
308 #define FT_SERVICE_POSTSCRIPT_CMAPS_H <freetype/internal/services/svpscmap.h>
309 #define FT_SERVICE_POSTSCRIPT_INFO_H <freetype/internal/services/svpsinfo.h>
310 #define FT_SERVICE_POSTSCRIPT_NAME_H <freetype/internal/services/svpostnm.h>
311 #define FT_SERVICE_SFNT_H <freetype/internal/services/svsfnt.h>
312 #define FT_SERVICE_TT_CMAP_H <freetype/internal/services/svttcmap.h>
313 #define FT_SERVICE_WINFNT_H <freetype/internal/services/svwinfnt.h>
314 #define FT_SERVICE_XFREE86_NAME_H <freetype/internal/services/svxf86nm.h>
320 #endif /* __FTSERV_H__ */