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Diffstat (limited to 'Build/source/libs/libttf/ttextend.c')
-rw-r--r-- | Build/source/libs/libttf/ttextend.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/Build/source/libs/libttf/ttextend.c b/Build/source/libs/libttf/ttextend.c new file mode 100644 index 00000000000..cb77e7ff885 --- /dev/null +++ b/Build/source/libs/libttf/ttextend.c @@ -0,0 +1,212 @@ +/******************************************************************* + * + * ttextend.h 2.0 + * + * Extensions Interface + * + * Copyright 1996-1999 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. + * + * This is an updated version of the extension component, now + * located in the main library's source directory. It allows + * the dynamic registration/use of various face object extensions + * through a simple API. + * + ******************************************************************/ + +#include "ttextend.h" +#include "ttengine.h" +#include "ttmemory.h" + +/* required by the tracing mode */ +#undef TT_COMPONENT +#define TT_COMPONENT trace_extend + + + struct TExtension_Registry_ + { + Int num_extensions; + Long cur_offset; + TExtension_Class classes[TT_MAX_EXTENSIONS]; + }; + + typedef struct TExtension_Registry_ TExtension_Registry; + typedef TExtension_Registry* PExtension_Registry; + + + + /* Initialize the extension component */ + + LOCAL_FUNC + TT_Error TTExtend_Init( PEngine_Instance engine ) + { + TT_Error error; + PExtension_Registry exts; + + + if ( ALLOC( exts, sizeof ( TExtension_Registry ) ) ) + return error; + + exts->num_extensions = 0; + exts->cur_offset = 0; + engine->extension_component = (void*)exts; + + return TT_Err_Ok; + } + + + /* Finalize the extension component */ + + LOCAL_FUNC + TT_Error TTExtend_Done( PEngine_Instance engine ) + { + FREE( engine->extension_component ); + return TT_Err_Ok; + } + + + /* Register a new extension */ + + EXPORT_FUNC + TT_Error TT_Register_Extension( PEngine_Instance engine, + Long id, + Long size, + PExt_Constructor create, + PExt_Destructor destroy ) + { + PExtension_Registry exts; + PExtension_Class clazz; + Int p; + + + exts = (PExtension_Registry)engine->extension_component; + if ( !exts ) + return TT_Err_Ok; + + p = exts->num_extensions; + + if ( p >= TT_MAX_EXTENSIONS ) + return TT_Err_Too_Many_Extensions; + + clazz = exts->classes + p; + clazz->id = id; + clazz->size = size; + clazz->build = create; + clazz->destroy = destroy; + + clazz->offset = exts->cur_offset; + + exts->num_extensions++; + exts->cur_offset += ( size + ALIGNMENT-1 ) & -ALIGNMENT; + + return TT_Err_Ok; + } + + + /* Query an extension block by extension_ID */ + + EXPORT_FUNC + TT_Error TT_Extension_Get( PFace face, + Long extension_id, + void** extension_block ) + { + PExtension_Registry registry; + PExtension_Class clazz; + Int n; + + + if ( !face->extension ) + return TT_Err_Extensions_Unsupported; + + registry = (PExtension_Registry)face->engine->extension_component; + + for ( n = 0; n < face->n_extensions; n++ ) + { + clazz = registry->classes + n; + if ( clazz->id == extension_id ) + { + *extension_block = (PByte)face->extension + clazz->offset; + return TT_Err_Ok; + } + } + + return TT_Err_Invalid_Extension_Id; + } + + + /* Destroy all extensions within a face object. Called by the */ + /* face object destructor. */ + + LOCAL_FUNC + TT_Error Extension_Destroy( PFace face ) + { + PEngine_Instance engine = face->engine; + PExtension_Registry registry; + PExtension_Class clazz; + Int n; + PByte ext; + + + registry = (PExtension_Registry)engine->extension_component; + + for ( n = 0; n < face->n_extensions; n++ ) + { + clazz = registry->classes + n; + ext = (PByte)face->extension + clazz->offset; + + /* the destructor is optional */ + if ( clazz->destroy ) + clazz->destroy( (void*)ext, face ); + } + + /* destroy the face's extension block too */ + FREE( face->extension ); + face->n_extensions = 0; + + return TT_Err_Ok; + } + + + /* Create an extension within a face object. Called by the */ + /* face object constructor. */ + + LOCAL_FUNC + TT_Error Extension_Create( PFace face ) + { + PEngine_Instance engine = face->engine; + PExtension_Registry registry; + PExtension_Class clazz; + TT_Error error; + Int n; + PByte ext; + + + registry = (PExtension_Registry)engine->extension_component; + + face->n_extensions = registry->num_extensions; + if ( ALLOC( face->extension, registry->cur_offset ) ) + return error; + + for ( n = 0; n < face->n_extensions; n++ ) + { + clazz = registry->classes + n; + ext = (PByte)face->extension + clazz->offset; + error = clazz->build( (void*)ext, face ); + if ( error ) + goto Fail; + } + return TT_Err_Ok; + + Fail: + Extension_Destroy( face ); + return error; + } + + +/* END */ |