Die on an OOM situation in many more cases....

base/process_util_mac.mm

Index: base/process_util_mac.mm
===================================================================
--- base/process_util_mac.mm	(revision 41837)
+++ base/process_util_mac.mm	(working copy)
@@ -11,12 +11,14 @@
 #include <mach/mach_init.h>
 #include <mach/task.h>
 #include <malloc/malloc.h>
+#import <objc/runtime.h>
 #include <spawn.h>
 #include <sys/mman.h>
 #include <sys/sysctl.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 
+#include <new>
 #include <string>
 
 #include "base/debug_util.h"
@@ -355,6 +357,10 @@
 
 namespace {
 
+bool g_oom_killer_enabled;
+
+// === C malloc/calloc/valloc/realloc ===
+
 typedef void* (*malloc_type)(struct _malloc_zone_t* zone,
                              size_t size);
 typedef void* (*calloc_type)(struct _malloc_zone_t* zone,
@@ -405,26 +411,87 @@
   return result;
 }
 
+// === C++ operator new ===
+
+void oom_killer_new() {
+  DebugUtil::BreakDebugger();
+}
+
+// === Core Foundation CFAllocators ===
+
+// This is the real structure of a CFAllocatorRef behind the scenes. See
+// http://opensource.apple.com/source/CF/CF-550/CFBase.c for details.
+struct ChromeCFAllocator {
+  _malloc_zone_t fake_malloc_zone;
+  void* allocator;
+  CFAllocatorContext context;
+};
+typedef ChromeCFAllocator* ChromeCFAllocatorRef;
+
+CFAllocatorAllocateCallBack g_old_cfallocator_system_default;
+CFAllocatorAllocateCallBack g_old_cfallocator_malloc;
+CFAllocatorAllocateCallBack g_old_cfallocator_malloc_zone;
+
+void* oom_killer_cfallocator_system_default(CFIndex alloc_size,
+                                            CFOptionFlags hint,
+                                            void* info) {
+  void* result = g_old_cfallocator_system_default(alloc_size, hint, info);
+  if (!result)
+    DebugUtil::BreakDebugger();
+  return result;
+}
+
+void* oom_killer_cfallocator_malloc(CFIndex alloc_size,
+                                    CFOptionFlags hint,
+                                    void* info) {
+  void* result = g_old_cfallocator_malloc(alloc_size, hint, info);
+  if (!result)
+    DebugUtil::BreakDebugger();
+  return result;
+}
+
+void* oom_killer_cfallocator_malloc_zone(CFIndex alloc_size,
+                                         CFOptionFlags hint,
+                                         void* info) {
+  void* result = g_old_cfallocator_malloc_zone(alloc_size, hint, info);
+  if (!result)
+    DebugUtil::BreakDebugger();
+  return result;
+}
+
+// === Cocoa NSObject allocation ===
+
+typedef id (*allocWithZone_t)(id, SEL, NSZone*);
+allocWithZone_t g_old_allocWithZone;
+
+id oom_killer_allocWithZone(id self, SEL _cmd, NSZone* zone)
+{
+  id result = g_old_allocWithZone(self, _cmd, zone);
+  if (!result)
+    DebugUtil::BreakDebugger();
+  return result;
+}
+
 }  // namespace
 
 void EnableTerminationOnOutOfMemory() {
+  if (g_oom_killer_enabled)
+    return;
+
+  g_oom_killer_enabled = true;
+
+  // === C malloc/calloc/valloc/realloc ===
+
+  // This approach is not perfect, as requests for amounts of memory larger than
+  // MALLOC_ABSOLUTE_MAX_SIZE (currently SIZE_T_MAX - (2 * PAGE_SIZE)) will
+  // still fail with a NULL rather than dying (see
+  // http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c for details).
+  // Unfortunately, it's the best we can do. Also note that this does not affect
+  // allocations from non-default zones.
+
   CHECK(!g_old_malloc && !g_old_calloc && !g_old_valloc && !g_old_realloc)
-      << "EnableTerminationOnOutOfMemory() called twice!";
+      << "Old allocators unexpectedly non-null";
 
-  // This approach is sub-optimal:
-  // - Requests for amounts of memory larger than MALLOC_ABSOLUTE_MAX_SIZE
-  //   (currently SIZE_T_MAX - (2 * PAGE_SIZE)) will still fail with a NULL
-  //   rather than dying (see
-  //   http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c for
-  //   details).
-  // - It is unclear whether allocations via the C++ operator new() are affected
-  //   by this (although it is likely).
-  // - This does not affect allocations from non-default zones.
-  // - It is unclear whether allocations from CoreFoundation's
-  //   kCFAllocatorDefault or +[NSObject alloc] are affected by this.
-  // Nevertheless this is better than nothing for now.
-  // TODO(avi):Do better. http://crbug.com/12673
-
   int32 major;
   int32 minor;
   int32 bugfix;
@@ -459,6 +526,62 @@
   if (zone_allocators_protected) {
     mprotect(reinterpret_cast<void*>(page_start), len, PROT_READ);
   }
+
+  // === C++ operator new ===
+
+  // Yes, operator new does call through to malloc, but this will catch failures
+  // that our imperfect handling of malloc cannot.
+
+  std::set_new_handler(oom_killer_new);
+
+  // === Core Foundation CFAllocators ===
+
+  // This will not catch allocation done by custom allocators, but will catch
+  // all allocation done by system-provided ones.
+
+  CHECK(!g_old_cfallocator_system_default && !g_old_cfallocator_malloc &&
+        !g_old_cfallocator_malloc_zone)
+      << "Old allocators unexpectedly non-null";
+
+  ChromeCFAllocatorRef allocator = const_cast<ChromeCFAllocatorRef>(
+      reinterpret_cast<const ChromeCFAllocator*>(kCFAllocatorSystemDefault));
+  g_old_cfallocator_system_default = allocator->context.allocate;
+  CHECK(g_old_cfallocator_system_default)
+      << "Failed to get kCFAllocatorSystemDefault allocation function.";
+  allocator->context.allocate = oom_killer_cfallocator_system_default;
+
+  allocator = const_cast<ChromeCFAllocatorRef>(
+      reinterpret_cast<const ChromeCFAllocator*>(kCFAllocatorMalloc));
+  g_old_cfallocator_malloc = allocator->context.allocate;
+  CHECK(g_old_cfallocator_malloc)
+      << "Failed to get kCFAllocatorMalloc allocation function.";
+  allocator->context.allocate = oom_killer_cfallocator_malloc;
+
+  allocator = const_cast<ChromeCFAllocatorRef>(
+      reinterpret_cast<const ChromeCFAllocator*>(kCFAllocatorMallocZone));
+  g_old_cfallocator_malloc_zone = allocator->context.allocate;
+  CHECK(g_old_cfallocator_malloc_zone)
+      << "Failed to get kCFAllocatorMallocZone allocation function.";
+  allocator->context.allocate = oom_killer_cfallocator_malloc_zone;
+
+  // === Cocoa NSObject allocation ===
+
+  // Note that both +[NSObject new] and +[NSObject alloc] call through to
+  // +[NSObject allocWithZone:].
+
+  CHECK(!g_old_allocWithZone)
+      << "Old allocator unexpectedly non-null";
+
+  Class nsobject_class = [NSObject class];
+  Method orig_method = class_getClassMethod(nsobject_class,
+                                            @selector(allocWithZone:));

[Mark Mentovai, 2010/03/18 19:43:10]

I'm still curious about what sel_getName(method_getName(orig_method)) would be
here - that might be the key to why this didn't work with
method_exchangeImplementations the first time you tried it.

+  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));
+

[Avi (use Gerrit), 2010/03/17 21:44:06]

removed blank line here.

 }
 
 }  // namespace base