Don't delete g_vlog_info

base/logging.cc

 // Copyright (c) 2011 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 "base/logging.h"
 
 #if defined(OS_WIN)
 #include <io.h>
 #include <windows.h>
 typedef HANDLE FileHandle;
@@ skipping 46 matching lines @@
 #include "base/safe_strerror_posix.h"
 #endif
 
 #if defined(OS_ANDROID)
 #include <android/log.h>
 #endif
 
 namespace logging {
 
 DcheckState g_dcheck_state = DISABLE_DCHECK_FOR_NON_OFFICIAL_RELEASE_BUILDS;
+
+namespace {
+
 VlogInfo* g_vlog_info = NULL;
+VlogInfo* g_vlog_info_prev = NULL;
 
 const char* const log_severity_names[LOG_NUM_SEVERITIES] = {
   "INFO", "WARNING", "ERROR", "ERROR_REPORT", "FATAL" };
 
 int min_log_level = 0;
 
 // The default set here for logging_destination will only be used if
 // InitLogging is not called.  On Windows, use a file next to the exe;
 // on POSIX platforms, where it may not even be possible to locate the
 // executable on disk, use stderr.
@@ skipping 265 matching lines @@
 #elif defined(OS_POSIX)
     log_file = fopen(log_file_name->c_str(), "a");
     if (log_file == NULL)
       return false;
 #endif
   }
 
   return true;
 }
 
+}  // namespace
+
+
 bool BaseInitLoggingImpl(const PathChar* new_log_file,
                          LoggingDestination logging_dest,
                          LogLockingState lock_log,
                          OldFileDeletionState delete_old,
                          DcheckState dcheck_state) {
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   g_dcheck_state = dcheck_state;
-  delete g_vlog_info;
-  g_vlog_info = NULL;
+
   // Don't bother initializing g_vlog_info unless we use one of the
   // vlog switches.
   if (command_line->HasSwitch(switches::kV) ||
       command_line->HasSwitch(switches::kVModule)) {
+    // NOTE: If g_vlog_info has already been initialized, it might be in use
+    // by another thread. Don't delete the old VLogInfo, just create a second
+    // one. We keep track of both to avoid memory leak warnings.
+    CHECK(!g_vlog_info_prev);
+    g_vlog_info_prev = g_vlog_info;
+
     g_vlog_info =
         new VlogInfo(command_line->GetSwitchValueASCII(switches::kV),
                      command_line->GetSwitchValueASCII(switches::kVModule),
                      &min_log_level);
   }
 
   LoggingLock::Init(lock_log, new_log_file);
 
   LoggingLock logging_lock;
 
@@ skipping 27 matching lines @@
 int GetMinLogLevel() {
   return min_log_level;
 }
 
 int GetVlogVerbosity() {
   return std::max(-1, LOG_INFO - GetMinLogLevel());
 }
 
 int GetVlogLevelHelper(const char* file, size_t N) {
   DCHECK_GT(N, 0U);
-  return g_vlog_info ?
-      g_vlog_info->GetVlogLevel(base::StringPiece(file, N - 1)) :
+  // Note: g_vlog_info may change on a different thread during startup
+  // (but will always be valid or NULL).
+  VlogInfo* vlog_info = g_vlog_info;
+  return vlog_info ?
+      vlog_info->GetVlogLevel(base::StringPiece(file, N - 1)) :
       GetVlogVerbosity();
 }
 
 void SetLogItems(bool enable_process_id, bool enable_thread_id,
                  bool enable_timestamp, bool enable_tickcount) {
   log_process_id = enable_process_id;
   log_thread_id = enable_thread_id;
   log_timestamp = enable_timestamp;
   log_tickcount = enable_tickcount;
 }
@@ skipping 420 matching lines @@
 
 // This was defined at the beginnig of this file.
 #undef write
 
 std::ostream& operator<<(std::ostream& o, const StringPiece& piece) {
   o.write(piece.data(), static_cast<std::streamsize>(piece.size()));
   return o;
 }
 
 }  // namespace base