added tc_malloc_skip_new_handler

This is port of corresponding chromium change at:
https://codereview.chromium.org/55333002/

Basic idea is that sometimes apps that use tc_set_new_mode in order to
have C++ out-of-memory handler catch OOMs in malloc, need to invoke
usual malloc that returns 0 on OOM.

That new API is exactly for that. It'll always return NULL on OOM even
if tc_new_mode is set to true.

src/debugallocation.cc

@@ -1486,3 +1486,9 @@ extern "C" PERFTOOLS_DLL_DECL struct mallinfo tc_mallinfo(void) __THROW {
 extern "C" PERFTOOLS_DLL_DECL size_t tc_malloc_size(void* ptr) __THROW {
   return MallocExtension::instance()->GetAllocatedSize(ptr);
 }
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_malloc_skip_new_handler(size_t size) __THROW {
+  void* result = DebugAllocate(size, MallocBlock::kMallocType);
+  MallocHook::InvokeNewHook(result, size);
+  return result;
+}

src/gperftools/tcmalloc.h.in

@@ -89,6 +89,7 @@ extern "C" {
                                             const char** patch) __THROW;
 
   PERFTOOLS_DLL_DECL void* tc_malloc(size_t size) __THROW;
+  PERFTOOLS_DLL_DECL void* tc_malloc_skip_new_handler(size_t size) __THROW;
   PERFTOOLS_DLL_DECL void tc_free(void* ptr) __THROW;
   PERFTOOLS_DLL_DECL void* tc_realloc(void* ptr, size_t size) __THROW;
   PERFTOOLS_DLL_DECL void* tc_calloc(size_t nmemb, size_t size) __THROW;

src/tcmalloc.cc

@@ -1735,4 +1735,10 @@ extern "C" PERFTOOLS_DLL_DECL size_t tc_malloc_size(void* ptr) __THROW {
   return MallocExtension::instance()->GetAllocatedSize(ptr);
 }
 
+extern "C" PERFTOOLS_DLL_DECL void* tc_malloc_skip_new_handler(size_t size)  __THROW {
+  void* result = do_malloc(size);
+  MallocHook::InvokeNewHook(result, size);
+  return result;
+}
+
 #endif  // TCMALLOC_USING_DEBUGALLOCATION

src/tests/tcmalloc_unittest.cc

@@ -1132,6 +1132,11 @@ static int RunAllTests(int argc, char** argv) {
     free(p1);
     VerifyDeleteHookWasCalled();
 
+    p1 = tc_malloc_skip_new_handler(10);
+    CHECK(p1 != NULL);
+    VerifyNewHookWasCalled();
+    free(p1);
+    VerifyDeleteHookWasCalled();
 
     p1 = calloc(10, 2);
     CHECK(p1 != NULL);

src/windows/gperftools/tcmalloc.h

@@ -79,6 +79,7 @@ extern "C" {
                                             const char** patch) __THROW;
 
   PERFTOOLS_DLL_DECL void* tc_malloc(size_t size) __THROW;
+  PERFTOOLS_DLL_DECL void* tc_malloc_skip_new_handler(size_t size) __THROW;
   PERFTOOLS_DLL_DECL void tc_free(void* ptr) __THROW;
   PERFTOOLS_DLL_DECL void* tc_realloc(void* ptr, size_t size) __THROW;
   PERFTOOLS_DLL_DECL void* tc_calloc(size_t nmemb, size_t size) __THROW;

src/windows/gperftools/tcmalloc.h.in

@@ -79,6 +79,7 @@ extern "C" {
                                             const char** patch) __THROW;
 
   PERFTOOLS_DLL_DECL void* tc_malloc(size_t size) __THROW;
+  PERFTOOLS_DLL_DECL void* tc_malloc_skip_new_handler(size_t size) __THROW;
   PERFTOOLS_DLL_DECL void tc_free(void* ptr) __THROW;
   PERFTOOLS_DLL_DECL void* tc_realloc(void* ptr, size_t size) __THROW;
   PERFTOOLS_DLL_DECL void* tc_calloc(size_t nmemb, size_t size) __THROW;