linux: improve warnings when NSS/PR shutdowns fail

base/nss_init.cc

 // Copyright (c) 2008 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/nss_init.h"
 
 #include <dlfcn.h>
 #include <nss.h>
 #include <plarena.h>
 #include <prerror.h>
@@ skipping 113 matching lines @@
     if (root_) {
       SECMOD_UnloadUserModule(root_);
       SECMOD_DestroyModule(root_);
       root_ = NULL;
     }
 
     // Have to clear the cache, or NSS_Shutdown fails with SEC_ERROR_BUSY
     SSL_ClearSessionCache();
 
     SECStatus status = NSS_Shutdown();
-    if (status != SECSuccess)
-      LOG(ERROR) << "NSS_Shutdown failed, leak?  See "
-                    "http://code.google.com/p/chromium/issues/detail?id=4609";
+    if (status != SECSuccess) {
+      // We LOG(INFO) because this failure is relatively harmless
+      // (leaking, but we're shutting down anyway).
+      LOG(INFO) << "NSS_Shutdown failed; see "
+                   "http://code.google.com/p/chromium/issues/detail?id=4609";
+    }
 
     PL_ArenaFinish();
 
     PRStatus prstatus = PR_Cleanup();
-    if (prstatus != PR_SUCCESS)
-      LOG(ERROR) << "PR_Cleanup failed?";
+    if (prstatus != PR_SUCCESS) {
+      // We LOG(ERROR) here because this failure is bad: it indicates
+      // a potential race.

[wtc, 2009/08/04 17:42:21]

Nit: "a potential race" => "NSPR isn't initialized and cleaned up on the same
thread"

+      LOG(ERROR) << "PR_Cleanup failed; see "
+                    "http://code.google.com/p/chromium/issues/detail?id=18410";
+    }
   }
 
  private:
   SECMODModule *root_;
 };
 
 }  // namespace
 
 namespace base {
 
 void EnsureNSSInit() {
   Singleton<NSSInitSingleton>::get();
 }
 
 }  // namespace base