X-Git-Url: http://git.sourceforge.jp/view?p=pf3gnuchains%2Fgcc-fork.git;a=blobdiff_plain;f=libobjc%2Finit.c;h=23ba41ba128b04ad52b1cc71c9bc22a34d4f78af;hp=8e60bed97c49d41a092a7cd2ab9a179603c5860b;hb=d32a1b12c47dbca08c63d97aaae3a464ed9d5015;hpb=84297d8d804abd36de7f0b8dccf8558c8a753183;ds=sidebyside diff --git a/libobjc/init.c b/libobjc/init.c index 8e60bed97c4..23ba41ba128 100644 --- a/libobjc/init.c +++ b/libobjc/init.c @@ -24,6 +24,10 @@ a copy of the GCC Runtime Library Exception along with this program; see the files COPYING3 and COPYING.RUNTIME respectively. If not, see . */ +/* Uncommented the following line to enable debug logging. Use this + only while debugging the runtime. */ +/* #define DEBUG 1 */ + #include "objc-private/common.h" #include "objc-private/error.h" #include "objc/runtime.h" @@ -56,6 +60,16 @@ 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 +101,7 @@ 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 @@ -95,9 +109,9 @@ BOOL __objc_dangling_categories = NO; /* !T:UNUSED */ static void objc_send_load (void); /* Inserts all the classes defined in module in a tree of classes that - resembles the class hierarchy. This tree is traversed in preorder + resembles the class hierarchy. This tree is traversed in preorder and the classes in its nodes receive the +load message if these - methods were not executed before. The algorithm ensures that when + methods were not executed before. The algorithm ensures that when the +load method of a class is executed all the superclasses have been already received the +load message. */ static void __objc_create_classes_tree (struct objc_module *module); @@ -110,13 +124,22 @@ 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 { +/* This is a node in the class tree hierarchy used to send +load + messages. */ +typedef struct objc_class_tree +{ + /* The class corresponding to the node. */ Class class; - struct objc_list *subclasses; /* `head' is pointer to an objc_class_tree */ + + /* This is a linked list of all the direct subclasses of this class. + 'head' points to a subclass node; 'tail' points to the next + objc_list node (whose 'head' points to another subclass node, + etc). */ + struct objc_list *subclasses; } objc_class_tree; -/* This is a linked list of objc_class_tree trees. The head of these - trees are root classes (their super class is Nil). These different +/* This is a linked list of objc_class_tree trees. The head of these + trees are root classes (their super class is Nil). These different trees represent different class hierarchies. */ static struct objc_list *__objc_class_tree_list = NULL; @@ -129,7 +152,7 @@ static cache_ptr __objc_load_methods = NULL; is really needed so that superclasses will get the message before subclasses. - This tree will contain classes which are being loaded (or have just + This tree may contain classes which are being loaded (or have just being loaded), and whose super_class pointers have not yet been resolved. This implies that their super_class pointers point to a string with the name of the superclass; when the first message is @@ -168,29 +191,30 @@ static Class class_superclass_of_class (Class class) /* Creates a tree of classes whose topmost class is directly inherited - from `upper' and the bottom class in this tree is - `bottom_class'. The classes in this tree are super classes of - `bottom_class'. `subclasses' member of each tree node point to the - next subclass tree node. */ + from `upper' and the bottom class in this tree is `bottom_class'. + If `upper' is Nil, creates a class hierarchy up to a root class. + The classes in this tree are super classes of `bottom_class'. The + `subclasses' member of each tree node point to the list of + subclasses for the node. */ static objc_class_tree * create_tree_of_subclasses_inherited_from (Class bottom_class, Class upper) { Class superclass; objc_class_tree *tree, *prev; - if (bottom_class->super_class) - superclass = objc_getClass ((char *) bottom_class->super_class); - else - superclass = Nil; - DEBUG_PRINTF ("create_tree_of_subclasses_inherited_from:"); - DEBUG_PRINTF ("bottom_class = %s, upper = %s\n", + DEBUG_PRINTF (" bottom_class = %s, upper = %s\n", (bottom_class ? bottom_class->name : NULL), (upper ? upper->name : NULL)); - tree = prev = objc_calloc (1, sizeof (objc_class_tree)); + superclass = class_superclass_of_class (bottom_class); + + prev = objc_calloc (1, sizeof (objc_class_tree)); prev->class = bottom_class; + if (superclass == upper) + return prev; + while (superclass != upper) { tree = objc_calloc (1, sizeof (objc_class_tree)); @@ -204,23 +228,23 @@ create_tree_of_subclasses_inherited_from (Class bottom_class, Class upper) } /* Insert the `class' into the proper place in the `tree' class - hierarchy. This function returns a new tree if the class has been + hierarchy. This function returns a new tree if the class has been successfully inserted into the tree or NULL if the class is not - part of the classes hierarchy described by `tree'. This function is - private to objc_tree_insert_class (), you should not call it + part of the classes hierarchy described by `tree'. This function + is private to objc_tree_insert_class (), you should not call it directly. */ static objc_class_tree * __objc_tree_insert_class (objc_class_tree *tree, Class class) { - DEBUG_PRINTF ("__objc_tree_insert_class: tree = %p, class = %s\n", - tree, class->name); + DEBUG_PRINTF ("__objc_tree_insert_class: tree = %p (root: %s), class = %s\n", + tree, ((tree && tree->class) ? tree->class->name : "Nil"), class->name); if (tree == NULL) return create_tree_of_subclasses_inherited_from (class, NULL); else if (class == tree->class) { /* `class' has been already inserted. */ - DEBUG_PRINTF ("1. class %s was previously inserted\n", class->name); + DEBUG_PRINTF (" 1. class %s was previously inserted\n", class->name); return tree; } else if (class_superclass_of_class (class) == tree->class) @@ -237,7 +261,7 @@ __objc_tree_insert_class (objc_class_tree *tree, Class class) the tree. */ if (((objc_class_tree *) list->head)->class == class) { - DEBUG_PRINTF ("2. class %s was previously inserted\n", + DEBUG_PRINTF (" 2. class %s was previously inserted\n", class->name); return tree; } @@ -249,7 +273,7 @@ __objc_tree_insert_class (objc_class_tree *tree, Class class) node = objc_calloc (1, sizeof (objc_class_tree)); node->class = class; tree->subclasses = list_cons (node, tree->subclasses); - DEBUG_PRINTF ("3. class %s inserted\n", class->name); + DEBUG_PRINTF (" 3. class %s inserted\n", class->name); return tree; } else @@ -275,7 +299,7 @@ __objc_tree_insert_class (objc_class_tree *tree, Class class) since nothing has been changed. */ subclasses->head = __objc_tree_insert_class (subclasses->head, class); - DEBUG_PRINTF ("4. class %s inserted\n", class->name); + DEBUG_PRINTF (" 4. class %s inserted\n", class->name); return tree; } } @@ -287,7 +311,7 @@ __objc_tree_insert_class (objc_class_tree *tree, Class class) objc_class_tree *new_tree = create_tree_of_subclasses_inherited_from (class, tree->class); tree->subclasses = list_cons (new_tree, tree->subclasses); - DEBUG_PRINTF ("5. class %s inserted\n", class->name); + DEBUG_PRINTF (" 5. class %s inserted\n", class->name); return tree; } } @@ -299,27 +323,26 @@ objc_tree_insert_class (Class class) { struct objc_list *list_node; objc_class_tree *tree; - + list_node = __objc_class_tree_list; while (list_node) { + /* Try to insert the class in this class hierarchy. */ tree = __objc_tree_insert_class (list_node->head, class); if (tree) { list_node->head = tree; - break; + return; } else list_node = list_node->tail; } - - /* If the list was finished but the class hasn't been inserted, - insert it here. */ - if (! list_node) - { - __objc_class_tree_list = list_cons (NULL, __objc_class_tree_list); - __objc_class_tree_list->head = __objc_tree_insert_class (NULL, class); - } + + /* If the list was finished but the class hasn't been inserted, we + don't have an existing class hierarchy that can accomodate it. + Create a new one. */ + __objc_class_tree_list = list_cons (NULL, __objc_class_tree_list); + __objc_class_tree_list->head = __objc_tree_insert_class (NULL, class); } /* Traverse tree in preorder. Used to send +load. */ @@ -402,10 +425,10 @@ __objc_send_load_using_method_list (struct objc_method_list *method_list, Class mth->method_imp, mth->method_imp); - DEBUG_PRINTF ("sending +load in class: %s\n", class->name); - /* Call +load. */ + DEBUG_PRINTF (" begin of [%s +load]\n", class->name); (*mth->method_imp) ((id)class, mth->method_name); + DEBUG_PRINTF (" end of [%s +load]\n", class->name); break; } @@ -421,6 +444,7 @@ __objc_send_load (objc_class_tree *tree, Class class = tree->class; struct objc_method_list *method_list = class->class_pointer->methods; + DEBUG_PRINTF ("+load: need to send load to class '%s'\n", class->name); __objc_send_load_using_method_list (method_list, class); } @@ -566,7 +590,7 @@ __objc_exec_class (struct objc_module *module) int i; - DEBUG_PRINTF ("received module: %s\n", module->name); + DEBUG_PRINTF ("\n__objc_exec_class (%p) - start processing module...\n", module); /* Check gcc version. */ init_check_module_version (module); @@ -583,7 +607,9 @@ __objc_exec_class (struct objc_module *module) __objc_init_selector_tables (); __objc_init_class_tables (); __objc_init_dispatch_tables (); - __objc_class_tree_list = list_cons (NULL, __objc_class_tree_list); + duplicate_classes = objc_hash_new (8, + (hash_func_type)objc_hash_ptr, + objc_compare_ptrs); __objc_load_methods = objc_hash_new (128, (hash_func_type)objc_hash_ptr, objc_compare_ptrs); @@ -600,11 +626,13 @@ __objc_exec_class (struct objc_module *module) /* Replace referenced selectors from names to SELs. */ if (selectors) - __objc_register_selectors_from_module (selectors); + { + DEBUG_PRINTF (" registering selectors\n"); + __objc_register_selectors_from_module (selectors); + } /* Parse the classes in the load module and gather selector information. */ - DEBUG_PRINTF ("gathering selectors from module: %s\n", module->name); for (i = 0; i < symtab->cls_def_cnt; ++i) { Class class = (Class) symtab->defs[i]; @@ -613,19 +641,29 @@ __objc_exec_class (struct objc_module *module) /* Make sure we have what we think. */ assert (CLS_ISCLASS (class)); assert (CLS_ISMETA (class->class_pointer)); - DEBUG_PRINTF ("phase 1, processing class: %s\n", class->name); + DEBUG_PRINTF (" installing class '%s'\n", class->name); + + /* Workaround for a bug in clang: Clang may set flags other than + _CLS_CLASS and _CLS_META even when compiling for the + traditional ABI (version 8), confusing our runtime. Try to + wipe these flags out. */ + if (CLS_ISCLASS (class)) + __CLS_INFO (class) = _CLS_CLASS; + else + __CLS_INFO (class) = _CLS_META; /* Initialize the subclass list to be NULL. In some cases it 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) @@ -637,11 +675,7 @@ __objc_exec_class (struct objc_module *module) methods. */ if (class) { - - DEBUG_PRINTF ("processing categories from (module,object): %s, %s\n", - module->name, - class->name); - + DEBUG_PRINTF (" installing category '%s (%s)'\n", category->class_name, category->category_name); /* Do instance methods. */ if (category->instance_methods) class_add_method_list (class, category->instance_methods); @@ -663,6 +697,7 @@ __objc_exec_class (struct objc_module *module) } else { + DEBUG_PRINTF (" delaying installation of category '%s (%s)'\n", category->class_name, category->category_name); /* The object to which the category methods belong can't be found. Save the information. */ unclaimed_categories = list_cons (category, unclaimed_categories); @@ -683,9 +718,7 @@ __objc_exec_class (struct objc_module *module) if (class) { - DEBUG_PRINTF ("attaching stored categories to object: %s\n", - class->name); - + DEBUG_PRINTF (" installing (delayed) category '%s (%s)'\n", category->class_name, category->category_name); list_remove_head (cell); if (category->instance_methods) @@ -725,9 +758,14 @@ __objc_exec_class (struct objc_module *module) "resolving the class links" at this point, which will setup all the class/superclass pointers. */ if (!unresolved_classes && objc_getClass ("Object")) - __objc_resolve_class_links (); + { + DEBUG_PRINTF (" resolving class links\n"); + __objc_resolve_class_links (); + } objc_mutex_unlock (__objc_runtime_mutex); + + DEBUG_PRINTF ("__objc_exec_class (%p) - finished processing module...\n\n", module); } /* This function needs to be called with the objc_runtime_mutex @@ -808,7 +846,8 @@ __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 +884,13 @@ __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. */ + DEBUG_PRINTF (" calling the load callback for class '%s'\n", class->name); + _objc_load_callback (class, 0); + } } /* Call the _objc_load_callback for categories. Don't register @@ -858,6 +901,8 @@ __objc_call_load_callback (struct objc_module *module) struct objc_category *category = symtab->defs[i + symtab->cls_def_cnt]; Class class = objc_getClass (category->class_name); + DEBUG_PRINTF (" calling the load callback for category '%s (%s)'\n", + category->class_name, category->category_name); _objc_load_callback (class, category); } } @@ -874,27 +919,41 @@ 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. */ - __objc_add_class_to_hash (class); - - /* Register all of the selectors in the class and meta class. */ - __objc_register_selectors_from_class (class); - __objc_register_selectors_from_class ((Class) class->class_pointer); - - /* Install the fake dispatch tables. */ - __objc_install_premature_dtable (class); - __objc_install_premature_dtable (class->class_pointer); - - /* Register the instance methods as class methods, this is only done - for root classes. */ - __objc_register_instance_methods_to_class (class); + if (__objc_add_class_to_hash (class)) + { + /* Register all of the selectors in the class and meta class. */ + __objc_register_selectors_from_class (class); + __objc_register_selectors_from_class ((Class) class->class_pointer); + + /* Install the fake dispatch tables. */ + __objc_install_premature_dtable (class); + __objc_install_premature_dtable (class->class_pointer); + + /* Register the instance methods as class methods, this is only + done for root classes. */ + __objc_register_instance_methods_to_class (class); + + if (class->protocols) + __objc_init_protocols (class->protocols); - if (class->protocols) - __objc_init_protocols (class->protocols); + return YES; + } + else + { + /* The module contains a duplicate class. Remember it so that + we will ignore it later. */ + DEBUG_PRINTF (" duplicate class '%s' - will be ignored\n", class->name); + objc_hash_add (&duplicate_classes, class, class); + return NO; + } } /* __objc_init_protocol must be called with __objc_runtime_mutex