Allow multiple logging::LogMessage{Handler,Listener}s

net/tools/stress_cache/stress_cache.cc

 // Copyright (c) 2012 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.
 
 // This is a simple application that stress-tests the crash recovery of the disk
 // cache. The main application starts a copy of itself on a loop, checking the
 // exit code of the child process. When the child dies in an unexpected way,
 // the main application quits.
 
 // The child application has two threads: one to exercise the cache in an
@@ skipping 366 matching lines @@
 
   RunSoon(thread->task_runner());
   return true;
 }
 
 void CrashHandler(const std::string& str) {
   g_crashing = true;
   base::debug::BreakDebugger();
 }
 
-bool MessageHandler(int severity, const char* file, int line,
-                    size_t message_start, const std::string& str) {
-  const size_t kMaxMessageLen = 48;
-  char message[kMaxMessageLen];
-  size_t len = std::min(str.length() - message_start, kMaxMessageLen - 1);
+class MessageListener : logging::LogMessageListener {
+ public:
+  void OnMessage(int severity,
+                 const char* file,
+                 int line,
+                 size_t message_start,
+                 const std::string& str) override {
+    const size_t kMaxMessageLen = 48;
+    char message[kMaxMessageLen];
+    size_t len = std::min(str.length() - message_start, kMaxMessageLen - 1);
 
-  memcpy(message, str.c_str() + message_start, len);
-  message[len] = '\0';
+    memcpy(message, str.c_str() + message_start, len);
+    message[len] = '\0';
 #if !defined(DISK_CACHE_TRACE_TO_LOG)
-  disk_cache::Trace("%s", message);
+    disk_cache::Trace("%s", message);
 #endif
-  return false;
-}
+  }
+};
 
 // -----------------------------------------------------------------------
 
 #if defined(OS_WIN)
 // {B9A153D4-31C3-48e4-9ABF-D54383F14A0D}
 const GUID kStressCacheTraceProviderName = {
     0xb9a153d4, 0x31c3, 0x48e4,
         { 0x9a, 0xbf, 0xd5, 0x43, 0x83, 0xf1, 0x4a, 0xd } };
 #endif
 
 int main(int argc, const char* argv[]) {
   // Setup an AtExitManager so Singleton objects will be destructed.
   base::AtExitManager at_exit_manager;
 
   if (argc < 2)
     return MasterCode();
 
   logging::SetLogAssertHandler(CrashHandler);
-  logging::SetLogMessageHandler(MessageHandler);
+  MessageListener listener;
 
 #if defined(OS_WIN)
   logging::LogEventProvider::Initialize(kStressCacheTraceProviderName);
 #else
   base::CommandLine::Init(argc, argv);
   logging::LoggingSettings settings;
   settings.logging_dest = logging::LOG_TO_SYSTEM_DEBUG_LOG;
   logging::InitLogging(settings);
 #endif
 
   // Some time for the memory manager to flush stuff.
   base::PlatformThread::Sleep(base::TimeDelta::FromSeconds(3));
   base::MessageLoopForIO message_loop;
 
   char* end;
   long int iteration = strtol(argv[1], &end, 0);
 
   if (!StartCrashThread()) {
     printf("failed to start thread\n");
     return kError;
   }
 
   StressTheCache(iteration);
   return 0;
 }