mac: Periodically shim new malloc zones immediately after startup.

base/allocator/allocator_interception_mac_unittest.mm

Index: base/allocator/allocator_interception_mac_unittest.mm
diff --git a/base/allocator/allocator_interception_mac_unittest.mm b/base/allocator/allocator_interception_mac_unittest.mm
new file mode 100644
index 0000000000000000000000000000000000000000..c919ca0e8a9a8fbd3c535e756823999e68758fdd
--- /dev/null
+++ b/base/allocator/allocator_interception_mac_unittest.mm
@@ -0,0 +1,64 @@
+// Copyright 2017 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 <mach/mach.h>
+
+#include "base/allocator/allocator_interception_mac.h"
+#include "base/allocator/allocator_shim.h"
+#include "base/allocator/malloc_zone_functions_mac.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace base {
+namespace allocator {
+
+namespace {
+void ResetMallocZone(ChromeMallocZone* zone) {
+  MallocZoneFunctions& functions = GetFunctionsForZone(zone);
+  ReplaceZoneFunctions(zone, &functions);
+}
+
+void ResetAllMallocZones() {
+  ChromeMallocZone* default_malloc_zone =
+      reinterpret_cast<ChromeMallocZone*>(malloc_default_zone());
+  ResetMallocZone(default_malloc_zone);
+
+  vm_address_t* zones;
+  unsigned int count;
+  kern_return_t kr = malloc_get_all_zones(mach_task_self(), 0, &zones, &count);
+  if (kr != KERN_SUCCESS)
+    return;
+  for (unsigned int i = 0; i < count; ++i) {
+    ChromeMallocZone* zone = reinterpret_cast<ChromeMallocZone*>(zones[i]);
+    ResetMallocZone(zone);
+  }
+}
+}  // namespace
+
+class AllocatorInterceptionTest : public testing::Test {
+ protected:
+  void TearDown() override {
+    ResetAllMallocZones();
+    ClearAllMallocZonesForTesting();
+  }
+};
+
+#if !defined(MEMORY_TOOL_REPLACES_ALLOCATOR)
+TEST_F(AllocatorInterceptionTest, ShimNewMallocZones) {
+  InitializeAllocatorShim();
+  ChromeMallocZone* default_malloc_zone =
+      reinterpret_cast<ChromeMallocZone*>(malloc_default_zone());
+
+  malloc_zone_t new_zone;
+  memset(&new_zone, 1, sizeof(malloc_zone_t));
+  malloc_zone_register(&new_zone);
+  EXPECT_NE(new_zone.malloc, default_malloc_zone->malloc);
+  ShimNewMallocZones();
+  EXPECT_EQ(new_zone.malloc, default_malloc_zone->malloc);
+
+  malloc_zone_unregister(&new_zone);
+}
+#endif
+
+}  // namespace allocator
+}  // namespace base