Terminate plugin processes on a delayed task to allow the plugins to shutdown gracefully, i.e. NP...

content/browser/child_process_launcher.cc

Index: content/browser/child_process_launcher.cc
===================================================================
--- content/browser/child_process_launcher.cc	(revision 86295)
+++ content/browser/child_process_launcher.cc	(working copy)
@@ -105,6 +105,7 @@
 #endif
       CommandLine* cmd_line) {
     scoped_ptr<CommandLine> cmd_line_deleter(cmd_line);
+    process_type_ = cmd_line->GetSwitchValueASCII(switches::kProcessType);
     base::ProcessHandle handle = base::kNullProcessHandle;
 #if defined(OS_WIN)
     handle = sandbox::StartProcessWithAccess(cmd_line, exposed_dir);
@@ -210,16 +211,30 @@
     if (!process_.handle())
       return;
 
+    const int kPluginProcessTerminateTimeoutMs = 2000;
+
     // On Posix, EnsureProcessTerminated can lead to 2 seconds of sleep!  So
     // don't this on the UI/IO threads.
-    BrowserThread::PostTask(
-        BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
-        NewRunnableFunction(
-            &ChildProcessLauncher::Context::TerminateInternal,
-#if defined(OS_LINUX)
-            zygote_,
-#endif
-            process_.handle()));
+    // Allow plugins to shutdown gracefully before terminating the process.
+    if (process_type_ == switches::kPluginProcess) {

[jam, 2011/05/23 22:32:59]

ChildProcessLauncher is the base class that's used by all child processes.  It
seems out of place to add this logic to it, which is specific to plugins.

Either way, what happens if we post a task to kill the plugin, and the browser
shuts before the task runs?  Then we can end up with a zombie plugin process,
which would be very bad (i.e. wouldn't allow auto-update etc).

+      BrowserThread::PostDelayedTask(
+          BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
+          NewRunnableFunction(
+              &ChildProcessLauncher::Context::TerminateInternal,
+  #if defined(OS_LINUX)
+              zygote_,
+  #endif
+              process_.handle()), kPluginProcessTerminateTimeoutMs);
+    } else {
+      BrowserThread::PostTask(
+          BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
+          NewRunnableFunction(
+              &ChildProcessLauncher::Context::TerminateInternal,
+  #if defined(OS_LINUX)
+              zygote_,
+  #endif
+              process_.handle()));
+    }
     process_.set_handle(base::kNullProcessHandle);
   }
 
@@ -257,6 +272,7 @@
   BrowserThread::ID client_thread_id_;
   base::Process process_;
   bool starting_;
+  std::string process_type_;
 
 #if defined(OS_LINUX)
   bool zygote_;