Get a filename of dumped heap profile in a V8 extension HeapProfilerDump().

third_party/tcmalloc/chromium/src/heap-profiler.cc

Index: third_party/tcmalloc/chromium/src/heap-profiler.cc
diff --git a/third_party/tcmalloc/chromium/src/heap-profiler.cc b/third_party/tcmalloc/chromium/src/heap-profiler.cc
index c86a3c2b010c23ea0f6c8eae44e90fdcb317ee45..4aee0cf4ec7eea1b8d34af05d245b2237b275784 100644
--- a/third_party/tcmalloc/chromium/src/heap-profiler.cc
+++ b/third_party/tcmalloc/chromium/src/heap-profiler.cc
@@ -272,7 +272,9 @@ static void NewHook(const void* ptr, size_t size);
 static void DeleteHook(const void* ptr);
 
 // Helper for HeapProfilerDump.
-static void DumpProfileLocked(const char* reason) {
+static void DumpProfileLocked(const char* reason,
+                              char* filename_buffer,
+                              size_t filename_buffer_length) {
   RAW_DCHECK(heap_lock.IsHeld(), "");
   RAW_DCHECK(is_on, "");
   RAW_DCHECK(!dumping, "");
@@ -282,18 +284,17 @@ static void DumpProfileLocked(const char* reason) {
   dumping = true;
 
   // Make file name
-  char file_name[1000];
   dump_count++;
-  snprintf(file_name, sizeof(file_name), "%s.%05d.%04d%s",
+  snprintf(filename_buffer, filename_buffer_length, "%s.%05d.%04d%s",
            filename_prefix, getpid(), dump_count, HeapProfileTable::kFileExt);
 
   // Dump the profile
-  RAW_VLOG(0, "Dumping heap profile to %s (%s)", file_name, reason);
+  RAW_VLOG(0, "Dumping heap profile to %s (%s)", filename_buffer, reason);
   // We must use file routines that don't access memory, since we hold
   // a memory lock now.
-  RawFD fd = RawOpenForWriting(file_name);
+  RawFD fd = RawOpenForWriting(filename_buffer);
   if (fd == kIllegalRawFD) {
-    RAW_LOG(ERROR, "Failed dumping heap profile to %s", file_name);
+    RAW_LOG(ERROR, "Failed dumping heap profile to %s", filename_buffer);
     dumping = false;
     return;
   }
@@ -312,10 +313,10 @@ static void DumpProfileLocked(const char* reason) {
 
 #if defined(TYPE_PROFILING)
   if (FLAGS_heap_profile_type_statistics) {
-    snprintf(file_name, sizeof(file_name), "%s.%05d.%04d.type",
+    snprintf(filename_buffer, filename_buffer_length, "%s.%05d.%04d.type",
              filename_prefix, getpid(), dump_count);
-    RAW_VLOG(0, "Dumping type statistics to %s", file_name);
-    heap_profile->DumpTypeStatistics(file_name);
+    RAW_VLOG(0, "Dumping type statistics to %s", filename_buffer);
+    heap_profile->DumpTypeStatistics(filename_buffer);
   }
 #endif  // defined(TYPE_PROFILING)
 
@@ -364,7 +365,8 @@ static void MaybeDumpProfileLocked() {
       last_dump_time = current_time;
     }
     if (need_to_dump) {
-      DumpProfileLocked(buf);
+      char filename_buffer[1000];
+      DumpProfileLocked(buf, filename_buffer, sizeof(filename_buffer));
 
       last_dump_alloc = total.alloc_size;
       last_dump_free = total.free_size;
@@ -619,7 +621,17 @@ extern "C" void HeapProfilerStop() {
 extern "C" void HeapProfilerDump(const char* reason) {
   SpinLockHolder l(&heap_lock);
   if (is_on && !dumping) {
-    DumpProfileLocked(reason);
+    char filename_buffer[1000];
+    DumpProfileLocked(reason, filename_buffer, sizeof(filename_buffer));
+  }
+}
+
+extern "C" void HeapProfilerDumpWithFileName(const char* reason,
+                                             char* dumped_filename_buffer,
+                                             int filename_buffer_length) {
+  SpinLockHolder l(&heap_lock);
+  if (is_on && !dumping) {
+    DumpProfileLocked(reason, dumped_filename_buffer, filename_buffer_length);
   }
 }