--- /dev/null
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import "Private/GULSwizzler.h"
+
+#import <objc/runtime.h>
+
+#import <GoogleUtilities/GULLogger.h>
+#import "../Common/GULLoggerCodes.h"
+
+#ifdef GUL_UNSWIZZLING_ENABLED
+#import <GoogleUtilities/GULSwizzlingCache.h>
+// We need a private method for an assert.
+#import <GoogleUtilities/GULSwizzlingCache_Private.h>
+#endif
+
+static GULLoggerService kGULLoggerSwizzler = @"[GoogleUtilites/MethodSwizzler]";
+
+dispatch_queue_t GetGULSwizzlingQueue() {
+ static dispatch_queue_t queue;
+ static dispatch_once_t onceToken;
+ dispatch_once(&onceToken, ^{
+ queue = dispatch_queue_create("com.google.GULSwizzler", DISPATCH_QUEUE_SERIAL);
+ });
+ return queue;
+}
+
+@implementation GULSwizzler
+
++ (void)swizzleClass:(Class)aClass
+ selector:(SEL)selector
+ isClassSelector:(BOOL)isClassSelector
+ withBlock:(nullable id)block {
+ dispatch_sync(GetGULSwizzlingQueue(), ^{
+ NSAssert(selector, @"The selector cannot be NULL");
+ NSAssert(aClass, @"The class cannot be Nil");
+ Class resolvedClass = aClass;
+ Method method = nil;
+ if (isClassSelector) {
+ method = class_getClassMethod(aClass, selector);
+ resolvedClass = object_getClass(aClass);
+ } else {
+ method = class_getInstanceMethod(aClass, selector);
+ }
+ NSAssert(method, @"You're attempting to swizzle a method that doesn't exist. (%@, %@)",
+ NSStringFromClass(resolvedClass), NSStringFromSelector(selector));
+ IMP newImp = imp_implementationWithBlock(block);
+
+#ifdef GUL_UNSWIZZLING_ENABLED
+ IMP currentImp = class_getMethodImplementation(resolvedClass, selector);
+ [[GULSwizzlingCache sharedInstance] cacheCurrentIMP:currentImp
+ forNewIMP:newImp
+ forClass:resolvedClass
+ withSelector:selector];
+#endif
+
+ const char *typeEncoding = method_getTypeEncoding(method);
+ __unused IMP originalImpOfClass =
+ class_replaceMethod(resolvedClass, selector, newImp, typeEncoding);
+
+#ifdef GUL_UNSWIZZLING_ENABLED
+ // If !originalImpOfClass, then the IMP came from a superclass.
+ if (originalImpOfClass) {
+ if (originalImpOfClass !=
+ [[GULSwizzlingCache sharedInstance] originalIMPOfCurrentIMP:currentImp]) {
+ GULLogWarning(kGULLoggerSwizzler, NO,
+ [NSString stringWithFormat:@"I-SWZ%06ld",
+ (long)kGULSwizzlerMessageCodeMethodSwizzling000],
+ @"Swizzling class: %@ SEL:%@ after it has been previously been swizzled.",
+ NSStringFromClass(resolvedClass), NSStringFromSelector(selector));
+ }
+ }
+#endif
+ });
+}
+
++ (void)unswizzleClass:(Class)aClass selector:(SEL)selector isClassSelector:(BOOL)isClassSelector {
+#ifdef GUL_UNSWIZZLING_ENABLED
+ dispatch_sync(GetGULSwizzlingQueue(), ^{
+ NSAssert(aClass != nil && selector != nil, @"You cannot unswizzle a nil class or selector.");
+ Method method = nil;
+ Class resolvedClass = aClass;
+ if (isClassSelector) {
+ resolvedClass = object_getClass(aClass);
+ method = class_getClassMethod(aClass, selector);
+ } else {
+ method = class_getInstanceMethod(aClass, selector);
+ }
+ NSAssert(method, @"Couldn't find the method you're unswizzling in the runtime.");
+ IMP originalImp =
+ [[GULSwizzlingCache sharedInstance] cachedIMPForClass:resolvedClass withSelector:selector];
+ NSAssert(originalImp, @"This class/selector combination hasn't been swizzled");
+ IMP currentImp = method_setImplementation(method, originalImp);
+ BOOL didRemoveBlock = imp_removeBlock(currentImp);
+ NSAssert(didRemoveBlock, @"Wasn't able to remove the block of a swizzled IMP.");
+ [[GULSwizzlingCache sharedInstance] clearCacheForSwizzledIMP:currentImp
+ selector:selector
+ aClass:resolvedClass];
+ });
+#else
+ NSAssert(NO, @"Unswizzling is disabled.");
+#endif
+}
+
++ (nullable IMP)originalImplementationForClass:(Class)aClass
+ selector:(SEL)selector
+ isClassSelector:(BOOL)isClassSelector {
+#ifdef GUL_UNSWIZZLING_ENABLED
+ __block IMP originalImp = nil;
+ dispatch_sync(GetGULSwizzlingQueue(), ^{
+ Class resolvedClass = isClassSelector ? object_getClass(aClass) : aClass;
+ originalImp =
+ [[GULSwizzlingCache sharedInstance] cachedIMPForClass:resolvedClass withSelector:selector];
+ NSAssert(originalImp, @"The IMP for this class/selector combo doesn't exist (%@, %@).",
+ NSStringFromClass(resolvedClass), NSStringFromSelector(selector));
+ });
+ return originalImp;
+#else
+ NSAssert(NO, @"Unswizzling is disabled and the original IMP is not cached.");
+ return nil;
+#endif
+}
+
++ (nullable IMP)currentImplementationForClass:(Class)aClass
+ selector:(SEL)selector
+ isClassSelector:(BOOL)isClassSelector {
+ NSAssert(selector, @"The selector cannot be NULL");
+ NSAssert(aClass, @"The class cannot be Nil");
+ if (selector == NULL || aClass == nil) {
+ return nil;
+ }
+ __block IMP currentIMP = nil;
+ dispatch_sync(GetGULSwizzlingQueue(), ^{
+ Method method = nil;
+ if (isClassSelector) {
+ method = class_getClassMethod(aClass, selector);
+ } else {
+ method = class_getInstanceMethod(aClass, selector);
+ }
+ NSAssert(method, @"The Method for this class/selector combo doesn't exist (%@, %@).",
+ NSStringFromClass(aClass), NSStringFromSelector(selector));
+ if (method == nil) {
+ return;
+ }
+ currentIMP = method_getImplementation(method);
+ NSAssert(currentIMP, @"The IMP for this class/selector combo doesn't exist (%@, %@).",
+ NSStringFromClass(aClass), NSStringFromSelector(selector));
+ });
+ return currentIMP;
+}
+
++ (BOOL)selector:(SEL)selector existsInClass:(Class)aClass isClassSelector:(BOOL)isClassSelector {
+ Method method = isClassSelector ? class_getClassMethod(aClass, selector)
+ : class_getInstanceMethod(aClass, selector);
+ return method != nil;
+}
+
++ (NSArray<id> *)ivarObjectsForObject:(id)object {
+ NSMutableArray *array = [NSMutableArray array];
+ unsigned int count;
+ Ivar *vars = class_copyIvarList([object class], &count);
+ for (NSUInteger i = 0; i < count; i++) {
+ const char *typeEncoding = ivar_getTypeEncoding(vars[i]);
+ // Check to see if the ivar is an object.
+ if (strncmp(typeEncoding, "@", 1) == 0) {
+ id ivarObject = object_getIvar(object, vars[i]);
+ [array addObject:ivarObject];
+ }
+ }
+ free(vars);
+ return array;
+}
+
+@end
fnp / wl-app.git / blobdiff