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

components/crash/content/app/crashpad.cc

 // Copyright 2015 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 "components/crash/content/app/crashpad.h"
 
 #include <stddef.h>
 #include <string.h>
 
 #include <algorithm>
@@ skipping 34 matching lines @@
 
 void SetCrashKeyValue(const base::StringPiece& key,
                       const base::StringPiece& value) {
   g_simple_string_dictionary->SetKeyValue(key.data(), value.data());
 }
 
 void ClearCrashKey(const base::StringPiece& key) {
   g_simple_string_dictionary->RemoveKey(key.data());
 }
 
-bool LogMessageHandler(int severity,
-                       const char* file,
-                       int line,
-                       size_t message_start,
-                       const std::string& string) {
+class LogMessageListener : logging::LogMessageListener {
+  void OnMessage(int severity,
+                 const char* file,
+                 int line,
+                 size_t message_start,
+                 const std::string& string) override;
+};
+
+void LogMessageListener::OnMessage(int severity,
+                                   const char* file,
+                                   int line,
+                                   size_t message_start,
+                                   const std::string& string) {
   // Only handle FATAL.
   if (severity != logging::LOG_FATAL) {
-    return false;
+    return;
   }
 
   // In case of an out-of-memory condition, this code could be reentered when
   // constructing and storing the key. Using a static is not thread-safe, but if
   // multiple threads are in the process of a fatal crash at the same time, this
   // should work.
   static bool guarded = false;
   if (guarded) {
-    return false;
+    return;
   }
   base::AutoReset<bool> guard(&guarded, true);
 
   // Only log last path component.  This matches logging.cc.
   if (file) {
     const char* slash = strrchr(file, '/');
     if (slash) {
       file = slash + 1;
     }
   }
 
   CHECK_LE(message_start, string.size());
   std::string message = base::StringPrintf("%s:%d: %s", file, line,
                                            string.c_str() + message_start);
   SetCrashKeyValue("LOG_FATAL", message);
 
   // Rather than including the code to force the crash here, allow the caller to
   // do it.
-  return false;
 }
 
 void DumpWithoutCrashing() {
   CRASHPAD_SIMULATE_CRASH();
 }
 
 void InitializeCrashpadImpl(bool initial_client,
                             const std::string& process_type,
                             bool embedded_handler) {
   static bool initialized = false;
@@ skipping 56 matching lines @@
   crash_reporter_client->RegisterCrashKeys();
 
   SetCrashKeyValue("ptype", browser_process ? base::StringPiece("browser")
                                             : base::StringPiece(process_type));
 #if defined(OS_POSIX)
   SetCrashKeyValue("pid", base::IntToString(getpid()));
 #elif defined(OS_WIN)
   SetCrashKeyValue("pid", base::IntToString(::GetCurrentProcessId()));
 #endif
 
-  logging::SetLogMessageHandler(LogMessageHandler);
+  // Intentionally leak the listener.
+  new LogMessageListener();
 
   // If clients called CRASHPAD_SIMULATE_CRASH() instead of
   // base::debug::DumpWithoutCrashing(), these dumps would appear as crashes in
   // the correct function, at the correct file and line. This would be
   // preferable to having all occurrences show up in DumpWithoutCrashing() at
   // the same file and line.
   base::debug::SetDumpWithoutCrashingFunction(DumpWithoutCrashing);
 
 #if defined(OS_MACOSX)
   // On Mac, we only want the browser to initialize the database, but not the
@@ skipping 160 matching lines @@
 
 // This helper is invoked by code in chrome.dll to wait for the handler start to
 // complete.
 void __declspec(dllexport) BlockUntilHandlerStartedImpl() {
   crash_reporter::BlockUntilHandlerStarted();
 }
 
 }  // extern "C"
 
 #endif  // OS_WIN