Thread-local trace-event buffers

content/browser/browser_shutdown_profile_dumper.cc

 // Copyright 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 "content/browser/browser_shutdown_profile_dumper.h"
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/debug/trace_event_impl.h"
@@ skipping 28 matching lines @@
     LOG(ERROR) << "Failed to open performance trace file: " <<
         file_name.value();
     return;
   }
   WriteString("{\"traceEvents\":");
   WriteString("[");
 
   base::debug::TraceLog::GetInstance()->Flush(
       base::Bind(&BrowserShutdownProfileDumper::WriteTraceDataCollected,
       base::Unretained(this)));
-
-  WriteString("]");
-  WriteString("}");
-  CloseFile();
 }
 
 base::FilePath BrowserShutdownProfileDumper::GetFileName() {
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   base::FilePath trace_file =
       command_line.GetSwitchValuePath(switches::kTraceShutdownFile);
 
   if (!trace_file.empty())
     return trace_file;
 
   // Default to saving the startup trace into the current dir.
   return base::FilePath().AppendASCII("chrometrace.log");
 }
 
 void BrowserShutdownProfileDumper::WriteTraceDataCollected(
-    const scoped_refptr<base::RefCountedString>& events_str) {
+    const scoped_refptr<base::RefCountedString>& events_str,
+    bool has_more_events) {
   if (!IsFileValid())
     return;
   if (blocks_) {
     // Blocks are not comma separated. Beginning with the second block we
     // start therefore to add one in front of the previous block.
     WriteString(",");
   }
   ++blocks_;
   WriteString(events_str->data());
+
+  if (!has_more_events) {
+    WriteString("]");
+    WriteString("}");
+    CloseFile();
+  }
 }
 
 bool BrowserShutdownProfileDumper::IsFileValid() {
   return dump_file_ && (ferror(dump_file_) == 0);
 }
 
 void BrowserShutdownProfileDumper::WriteString(const std::string& string) {
   WriteChars(string.data(), string.size());
 }
 
@@ skipping 10 matching lines @@
 }
 
 void BrowserShutdownProfileDumper::CloseFile() {
   if (!dump_file_)
     return;
   file_util::CloseFile(dump_file_);
   dump_file_ = NULL;
 }
 
 }  // namespace content