diff options
| -rw-r--r-- | libobjc/ChangeLog | 12 | ||||
| -rw-r--r-- | libobjc/init.c | 66 | ||||
| -rw-r--r-- | libobjc/objc-private/runtime.h | 2 |
3 files changed, 60 insertions, 20 deletions
diff --git a/libobjc/ChangeLog b/libobjc/ChangeLog index e75730251d0..d1521f94ce9 100644 --- a/libobjc/ChangeLog +++ b/libobjc/ChangeLog @@ -1,5 +1,17 @@ 2010-12-22 Nicola Pero <nicola.pero@meta-innovation.com> + * init.c (duplicate_classes): New. + (__objc_exec_class): Initialize duplicate_classes. + (__objc_create_classes_tree): Ignore classes in the + duplicate_classes table. + (__objc_call_load_callback): Same. + (__objc_init_class): If a duplicate class is found, add it to + duplicate_classes instead of aborting. Return YES if the class is + not a duplicate, and NO if it is. + * objc-private/runtime.h (__objc_init_class): Updated prototype. + +2010-12-22 Nicola Pero <nicola.pero@meta-innovation.com> + * objc-private/objc-list.h: Reindented file. No code changes. * objc-private/sarray.h: Same change. diff --git a/libobjc/init.c b/libobjc/init.c index 0401fa432e9..d19355e3270 100644 --- a/libobjc/init.c +++ b/libobjc/init.c @@ -56,6 +56,16 @@ static struct objc_list *unclaimed_proto_list = 0; /* !T:MUTEX */ /* List of unresolved static instances. */ static struct objc_list *uninitialized_statics = 0; /* !T:MUTEX */ +/* List of duplicated classes found while loading modules. If we find + a class twice, we ignore it the second time. On some platforms, + where the order in which modules are loaded is well defined, this + allows you to replace a class in a shared library by linking in a + new implementation which is loaded in in the right order, and which + overrides the existing one. + + Protected by __objc_runtime_mutex. */ +static cache_ptr duplicate_classes = NULL; + /* Global runtime "write" mutex. Having a single mutex prevents deadlocks, but reduces concurrency. To improve concurrency, some groups of functions in the runtime have their own separate mutex @@ -87,7 +97,7 @@ static void __objc_class_add_protocols (Class, struct objc_protocol_list *); /* Load callback hook. */ void (*_objc_load_callback) (Class class, struct objc_category *category) = 0; /* !T:SAFE */ -/* Are all categories/classes resolved? */ +/* Are all categories/classes resolved ? */ BOOL __objc_dangling_categories = NO; /* !T:UNUSED */ /* Sends +load to all classes and categories in certain @@ -110,9 +120,11 @@ static void __objc_call_load_callback (struct objc_module *module); installed in the runtime. */ static BOOL class_is_subclass_of_class (Class class, Class superclass); -typedef struct objc_class_tree { +typedef struct objc_class_tree +{ Class class; - struct objc_list *subclasses; /* `head' is pointer to an objc_class_tree */ + struct objc_list *subclasses; /* `head' is a pointer to an + objc_class_tree. */ } objc_class_tree; /* This is a linked list of objc_class_tree trees. The head of these @@ -583,6 +595,9 @@ __objc_exec_class (struct objc_module *module) __objc_init_selector_tables (); __objc_init_class_tables (); __objc_init_dispatch_tables (); + duplicate_classes = objc_hash_new (8, + (hash_func_type)objc_hash_ptr, + objc_compare_ptrs); __objc_class_tree_list = list_cons (NULL, __objc_class_tree_list); __objc_load_methods = objc_hash_new (128, (hash_func_type)objc_hash_ptr, @@ -619,13 +634,14 @@ __objc_exec_class (struct objc_module *module) isn't and this crashes the program. */ class->subclass_list = NULL; - __objc_init_class (class); - - /* Check to see if the superclass is known in this point. If - it's not add the class to the unresolved_classes list. */ - if (superclass && ! objc_getClass (superclass)) - unresolved_classes = list_cons (class, unresolved_classes); - } + if (__objc_init_class (class)) + { + /* Check to see if the superclass is known in this point. If + it's not add the class to the unresolved_classes list. */ + if (superclass && ! objc_getClass (superclass)) + unresolved_classes = list_cons (class, unresolved_classes); + } + } /* Process category information from the module. */ for (i = 0; i < symtab->cat_def_cnt; ++i) @@ -637,7 +653,6 @@ __objc_exec_class (struct objc_module *module) methods. */ if (class) { - DEBUG_PRINTF ("processing categories from (module,object): %s, %s\n", module->name, class->name); @@ -808,7 +823,8 @@ __objc_create_classes_tree (struct objc_module *module) { Class class = (Class) symtab->defs[i]; - objc_tree_insert_class (class); + if (!objc_hash_is_key_in_hash (duplicate_classes, class)) + objc_tree_insert_class (class); } /* Now iterate over "claimed" categories too (ie, categories that @@ -845,9 +861,12 @@ __objc_call_load_callback (struct objc_module *module) for (i = 0; i < symtab->cls_def_cnt; i++) { Class class = (Class) symtab->defs[i]; - - /* Call the _objc_load_callback for this class. */ - _objc_load_callback (class, 0); + + if (!objc_hash_is_key_in_hash (duplicate_classes, class)) + { + /* Call the _objc_load_callback for this class. */ + _objc_load_callback (class, 0); + } } /* Call the _objc_load_callback for categories. Don't register @@ -874,8 +893,11 @@ init_check_module_version (struct objc_module *module) } } -/* __objc_init_class must be called with __objc_runtime_mutex already locked. */ -void +/* __objc_init_class must be called with __objc_runtime_mutex already + locked. Return YES if the class could be setup; return NO if the + class could not be setup because a class with the same name already + exists. */ +BOOL __objc_init_class (Class class) { /* Store the class in the class table and assign class numbers. */ @@ -895,10 +917,16 @@ __objc_init_class (Class class) if (class->protocols) __objc_init_protocols (class->protocols); + + return YES; } else - _objc_abort ("Module contains duplicate class '%s'\n", - class->name); + { + /* The module contains a duplicate class. Remember it so that + we will ignore it later. */ + objc_hash_add (&duplicate_classes, class, class); + return NO; + } } /* __objc_init_protocol must be called with __objc_runtime_mutex diff --git a/libobjc/objc-private/runtime.h b/libobjc/objc-private/runtime.h index f4ad2e7178e..5406294f2c3 100644 --- a/libobjc/objc-private/runtime.h +++ b/libobjc/objc-private/runtime.h @@ -57,7 +57,7 @@ extern void __objc_update_dispatch_table_for_class (Class);/* (objc-msg.c) */ extern int __objc_init_thread_system (void); /* thread.c */ extern int __objc_fini_thread_system (void); /* thread.c */ -extern void __objc_init_class (Class class); /* init.c */ +extern BOOL __objc_init_class (Class class); /* init.c */ extern void class_add_method_list (Class, struct objc_method_list *); /* Registering instance methods as class methods for root classes */ |