Fix up GTM_METHOD_CHECK so that it doesn't need the objectivec runtime calls.

1 files changed, 25 insertions, 44 deletions

diff --git a/DebugUtils/GTMMethodCheck.h b/DebugUtils/GTMMethodCheck.h
index 7b0919b..9fad81d 100644
--- a/DebugUtils/GTMMethodCheck.h
+++ b/DebugUtils/GTMMethodCheck.h
@@ -1,14 +1,14 @@
 //
 //  GTMMethodCheck.h
-//  
-//  Copyright 2006-2008 Google Inc.
+//
+//  Copyright 2006-2016 Google Inc.
 //
 //  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
@@ -21,66 +21,47 @@
 #import <sysexits.h>
 
 /// A macro for enforcing debug time checks to make sure all required methods are linked in
-// 
+//
 // When using categories, it can be very easy to forget to include the
-// implementation of a category. 
+// implementation of a category.
 // Let's say you had a class foo that depended on method bar of class baz, and
 // method bar was implemented as a member of a category.
 // You could add the following code:
-// @implementation foo
+//
 // GTM_METHOD_CHECK(baz, bar)
-// @end
+//
 // and the code would check to make sure baz was implemented just before main
 // was called. This works for both dynamic libraries, and executables.
 //
-// Classes (or one of their superclasses) being checked must conform to the 
-// NSObject protocol. We will check this, and spit out a warning if a class does 
-// not conform to NSObject.
 //
 // This is not compiled into release builds.
 
 #ifdef DEBUG
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-  
-// If you get an error for GTMMethodCheckMethodChecker not being defined, 
-// you need to link in GTMMethodCheck.m. We keep it hidden so that we can have 
-// it living in several separate images without conflict.
-// Functions with the ((constructor)) attribute are called after all +loads
-// have been called. See "Initializing Objective-C Classes" in 
-// http://developer.apple.com/documentation/DeveloperTools/Conceptual/DynamicLibraries/Articles/DynamicLibraryDesignGuidelines.html#//apple_ref/doc/uid/TP40002013-DontLinkElementID_20
-  
-__attribute__ ((constructor, visibility("hidden"))) void GTMMethodCheckMethodChecker(void);
-  
-#ifdef __cplusplus
-};
-#endif
-
 // This is the "magic".
-// A) we need a multi layer define here so that the stupid preprocessor
-//    expands __LINE__ out the way we want it. We need LINE so that each of
-//    out GTM_METHOD_CHECKs generates a unique class method for the class.
+// A) we need a multi layer define here so that the preprocessor expands
+//    __LINE__ the way we want it. We need __LINE__ so that each of our
+//    GTM_METHOD_CHECKs generates a unique function name.
 #define GTM_METHOD_CHECK(class, method) GTM_METHOD_CHECK_INNER(class, method, __LINE__)
-#define GTM_METHOD_CHECK_INNER(class, method, line) GTM_METHOD_CHECK_INNER_INNER(class, method, line)
+#define GTM_METHOD_CHECK_INNER(class, method, line) \
+    GTM_METHOD_CHECK_INNER_INNER(class, method, line)
 
-// B) Create up a class method called xxGMethodCheckMethod+class+line that the 
-//    GTMMethodCheckMethodChecker function can look for and call. We
-//    look for GTMMethodCheckMethodChecker to enforce linkage of
-//    GTMMethodCheck.m.
+// B) define a function that is called at startup to check that |class| has an
+//    implementation for |method| (either a class method or an instance method).
 #define GTM_METHOD_CHECK_INNER_INNER(class, method, line) \
-+ (void)xxGTMMethodCheckMethod ## class ## line { \
-  void (*addr)() = GTMMethodCheckMethodChecker; \
-  if (addr && ![class instancesRespondToSelector:@selector(method)] \
-      && ![class respondsToSelector:@selector(method)]) { \
-    fprintf(stderr, "%s:%d: error: We need method '%s' to be linked in for class '%s'\n", \
-            __FILE__, line, #method, #class); \
-    exit(EX_SOFTWARE); \
+__attribute__ ((constructor, visibility("hidden"))) \
+    static void xxGTMMethodCheckMethod ## class ## line () { \
+  @autoreleasepool { \
+    if (![class instancesRespondToSelector:@selector(method)] \
+        && ![class respondsToSelector:@selector(method)]) { \
+      fprintf(stderr, "%s:%d: error: We need method '%s' to be linked in for class '%s'\n", \
+              __FILE__, line, #method, #class); \
+      exit(EX_SOFTWARE); \
+    } \
   } \
 }
 
-#else // !DEBUG
+#else  // DEBUG
 
 // Do nothing in release.
 #define GTM_METHOD_CHECK(class, method)