Make possible to check memory allocations inside chromium

base/process/memory_mac.mm

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/process/memory.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 #include <errno.h>
 #include <mach/mach.h>
 #include <mach/mach_vm.h>
@@ skipping 484 matching lines @@
 id oom_killer_allocWithZone(id self, SEL _cmd, NSZone* zone)
 {
   id result = g_old_allocWithZone(self, _cmd, zone);
   if (!result)
     debug::BreakDebugger();
   return result;
 }
 
 }  // namespace
 
-void* UncheckedMalloc(size_t size) {
+bool UncheckedMalloc(size_t size, void** result) {
   if (g_old_malloc) {
 #if ARCH_CPU_32_BITS
     ScopedClearErrno clear_errno;
     ThreadLocalBooleanAutoReset flag(g_unchecked_alloc.Pointer(), true);
 #endif  // ARCH_CPU_32_BITS
-    return g_old_malloc(malloc_default_zone(), size);
+    return *result = g_old_malloc(malloc_default_zone(), size);
+  } else {
+    *result = malloc(size);
   }
-  return malloc(size);
+
+  return *result;
 }
 
-void* UncheckedCalloc(size_t num_items, size_t size) {
+bool UncheckedCalloc(size_t num_items, size_t size, void** result) {
   if (g_old_calloc) {
 #if ARCH_CPU_32_BITS
     ScopedClearErrno clear_errno;
     ThreadLocalBooleanAutoReset flag(g_unchecked_alloc.Pointer(), true);
 #endif  // ARCH_CPU_32_BITS
-    return g_old_calloc(malloc_default_zone(), num_items, size);
+    *result = g_old_calloc(malloc_default_zone(), num_items, size);
+  } else {
+    *result = calloc(num_items, size);
   }
-  return calloc(num_items, size);
+
+  return *result;

[jar (doing other things), 2014/02/26 03:59:52]

nit: Clearer might be:
return NULL != *result;

+}
+
+void* UncheckedMalloc(size_t size) {
+  void* address;
+  bool result ALLOW_UNUSED = UncheckedMalloc(size, &address);

[jar (doing other things), 2014/02/26 03:59:52]

It is a bit distressing to see both a bool return, and a NULL vs non-NULL
return.  Replication of results leads to bugs IMO.

IMO, better to have one source of truth... and it sure seems ilke the pointer is
a safer thing to use consistently.

+  return address;
+}
+
+void* UncheckedCalloc(size_t num_items, size_t size) {
+  void* address;
+  bool result ALLOW_UNUSED = UncheckedCalloc(num_items, size, &address);
+  return address;
 }
 
 void EnableTerminationOnOutOfMemory() {
   if (g_oom_killer_enabled)
     return;
 
   g_oom_killer_enabled = true;
 
   // === C malloc/calloc/valloc/realloc/posix_memalign ===
 
@@ skipping 186 matching lines @@
                                             @selector(allocWithZone:));
   g_old_allocWithZone = reinterpret_cast<allocWithZone_t>(
       method_getImplementation(orig_method));
   CHECK(g_old_allocWithZone)
       << "Failed to get allocWithZone allocation function.";
   method_setImplementation(orig_method,
                            reinterpret_cast<IMP>(oom_killer_allocWithZone));
 }
 
 }  // namespace base