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

3 files changed, 29 insertions, 181 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)
diff --git a/DebugUtils/GTMMethodCheck.m b/DebugUtils/GTMMethodCheck.m
index 0ff795e..5a9a363 100644
--- a/DebugUtils/GTMMethodCheck.m
+++ b/DebugUtils/GTMMethodCheck.m
@@ -16,103 +16,5 @@
 //  the License.
 //
 
-// Don't want any of this in release builds
-#ifdef DEBUG
-#import "GTMDefines.h"
-#import "GTMMethodCheck.h"
-#import "GTMObjC2Runtime.h"
-#import <dlfcn.h>
-
-void GTMMethodCheckMethodChecker(void) {
-  // Run through all the classes looking for class methods that are
-  // prefixed with xxGMMethodCheckMethod. If it finds one, it calls it.
-  // See GTMMethodCheck.h to see what it does.
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
-#else
-  @autoreleasepool {
-#endif
-  // Since GTMMethodCheckMethodChecker is not exported, we should always find
-  // the copy in our local image. This will give us access to our local image
-  // in the methodCheckerInfo structure.
-  Dl_info methodCheckerInfo;
-  int foundMethodChecker = dladdr(GTMMethodCheckMethodChecker,
-                                  &methodCheckerInfo);
-  _GTMDevAssert(foundMethodChecker, @"GTMMethodCheckMethodChecker: Unable to "
-                @"get dladdr for GTMMethodCheckMethodChecker");
-  int numClasses = 0;
-  int newNumClasses = objc_getClassList(NULL, 0);
-  int i;
-  Class *classes = NULL;
-  while (numClasses < newNumClasses) {
-    numClasses = newNumClasses;
-    classes = (Class *)realloc(classes, sizeof(Class) * numClasses);
-    _GTMDevAssert(classes, @"Unable to allocate memory for classes");
-    newNumClasses = objc_getClassList(classes, numClasses);
-  }
-  for (i = 0; i < numClasses && classes; ++i) {
-    Class cls = classes[i];
-    const char *className = class_getName(cls);
-    _GTMDevAssert(className, @"GTMMethodCheckMethodChecker: Unable to "
-                  @"get className for class %d", i);
-    // Since we are looking for a class method (+xxGMMethodCheckMethod...)
-    // we need to query the isa pointer to see what methods it support, but
-    // send the method (if it's supported) to the class itself.
-    if (strcmp(className, "__ARCLite__") == 0) {
-      // __ARCLite__ is "magic" and does not have a metaClass.
-      continue;
-    }
-    Class metaClass = objc_getMetaClass(className);
-    _GTMDevAssert(metaClass, @"GTMMethodCheckMethodChecker: Unable to "
-                  @"get metaClass for %s", className);
-    unsigned int count;
-    Method *methods = class_copyMethodList(metaClass, &count);
-    if (count == 0) {
-      continue;
-    }
-    _GTMDevAssert(methods, @"GTMMethodCheckMethodChecker: Unable to "
-                  @"get methods for class %s", className);
-
-    unsigned int j;
-    for (j = 0; j < count; ++j) {
-      SEL selector = method_getName(methods[j]);
-      _GTMDevAssert(selector, @"GTMMethodCheckMethodChecker: Unable to "
-                    @"get selector for method %d of %s", j, className);
-      const char *name = sel_getName(selector);
-      _GTMDevAssert(selector, @"GTMMethodCheckMethodChecker: Unable to "
-                    @"get name for method %d of %s", j, className);
-      if (strstr(name, "xxGTMMethodCheckMethod") == name) {
-        Dl_info methodInfo;
-        IMP imp = method_getImplementation(methods[j]);
-        _GTMDevAssert(selector, @"GTMMethodCheckMethodChecker: Unable to "
-                      @"get IMP for method %s of %s", name, className);
-        int foundMethod = dladdr(imp, &methodInfo);
-        _GTMDevAssert(foundMethod, @"GTMMethodCheckMethodChecker: Unable to "
-                      @"get dladdr for method %s of %s", name, className);
-
-        // Check to make sure that the method we are checking comes from the
-        // same image that we are in. We compare the address of the local
-        // image (stored in |methodCheckerInfo| as noted above) with the
-        // address of the image which implements the method we want to
-        // check. If they match we continue. This does two things:
-        // a) minimizes the amount of calls we make to the xxxGTMMethodCheck
-        //    methods. They should only be called once.
-        // b) prevents initializers for various classes being called too
-        //    early
-        if (methodCheckerInfo.dli_fbase == methodInfo.dli_fbase) {
-          void (*func)(id, SEL) = (void *)imp;
-          func(cls, selector);
-        }
-      }
-    }
-    free(methods);
-  }
-  free(classes);
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-  [pool drain];
-#else
-  }  // @autoreleasepool
-#endif
-}
-
-#endif  // DEBUG
+// TODO(dmaclach): This file is no longer needed. Delete once we have cleaned
+//                 up GTM projects.
diff --git a/DebugUtils/GTMMethodCheckTest.m b/DebugUtils/GTMMethodCheckTest.m
index 1fba238..9d90563 100644
--- a/DebugUtils/GTMMethodCheckTest.m
+++ b/DebugUtils/GTMMethodCheckTest.m
@@ -15,40 +15,5 @@
 //  the License.
 //
 
-#import "GTMSenTestCase.h"
-#import "GTMMethodCheck.h"
-
-static BOOL gTestCheckVar = NO;
-
-@interface GTMMethodCheckTest : GTMTestCase
-+ (void)GTMMethodCheckTestClassMethod;
-- (void)GTMMethodCheckTestMethod;
-@end
-
-@implementation GTMMethodCheckTest
-GTM_METHOD_CHECK(GTMMethodCheckTest, GTMMethodCheckTestMethod);
-GTM_METHOD_CHECK(GTMMethodCheckTest, GTMMethodCheckTestClassMethod);
-
-- (void)GTMMethodCheckTestMethod {
-}
-
-+ (void)GTMMethodCheckTestClassMethod {
-}
-
-+ (void)xxGTMMethodCheckMethodTestCheck {
-  // This gets called because of its special name by GMMethodCheck
-  // Look at the Macros in GMMethodCheck.h for details.
-  gTestCheckVar = YES;
-}
-
-- (void)testGTMMethodCheck {
-#ifdef DEBUG
-  // GTMMethodCheck only runs in debug
-  STAssertTrue(gTestCheckVar, @"Should be true");
-#endif
-
-  // Next two calls just verify our code coverage
-  [self GTMMethodCheckTestMethod];
-  [[self class] GTMMethodCheckTestClassMethod];
-}
-@end
+// TODO(dmaclach): This file no longer needed. Delete once we have cleaned up
+// GTM projects.