Added code for renderer to cleanly exit.

content/renderer/renderer_main.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.
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/debug/debugger.h"
 #include "base/debug/trace_event.h"
 #include "base/i18n/rtl.h"
 #include "base/memory/ref_counted.h"
@@ skipping 108 matching lines @@
     if (!begin_process_message_.is_null())
       process_times_->AddTime(base::TimeTicks::Now() - begin_process_message_);
   }
 
  private:
   base::TimeTicks begin_process_message_;
   base::Histogram* const process_times_;
   DISALLOW_COPY_AND_ASSIGN(RendererMessageLoopObserver);
 };
 
+#if defined(RENDERER_SIGTERM_HANDLER)
+static void SigtermHandler(int signum)
+{

[Evan Martin, 2012/03/26 17:17:25]

curly should be on same line of function decl (see surrounding code)

+  LOG(INFO) << "SIGTERM caught by the renderer process. Calling exit().";

[Evan Martin, 2012/03/26 17:17:25]

I think LOG() probably does a bunch of stuff that isn't safe from a signal
handler.  You might want to just write() to the stderr fd.

+  exit(signum);
+}
+
+static void AddSigtermHandler()
+{
+  struct sigaction termAction;

[Evan Martin, 2012/03/26 17:17:25]

variable names should be like term_action

+  termAction.sa_handler = SigtermHandler;
+  sigfillset(&termAction.sa_mask);
+  termAction.sa_flags = 0;
+  LOG(INFO) << "Installing SIGTERM handler to the renderer process.";
+  sigaction(SIGTERM, &termAction, NULL);
+  LOG(INFO) << "Added SIGTERM handler to the renderer process.";

[Evan Martin, 2012/03/26 17:17:25]

Rather than this, perhaps you should just check the return value of sigaction? 
grep the code for use of the PLOG() macro to automatically strerror(errno).

+}
+#endif
+
 // mainline routine for running as the Renderer process
 int RendererMain(const content::MainFunctionParams& parameters) {
   TRACE_EVENT_BEGIN_ETW("RendererMain", 0, "");
 
   const CommandLine& parsed_command_line = parameters.command_line;
 
 #if defined(OS_MACOSX)
   base::mac::ScopedNSAutoreleasePool* pool = parameters.autorelease_pool;
   InstallFrameworkHacks();
 #endif  // OS_MACOSX
@@ skipping 86 matching lines @@
     }
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
     RenderProcessImpl render_process;
     new RenderThreadImpl();
 #endif
 
     platform.RunSandboxTests();
 
     startup_timer.Stop();  // End of Startup Time Measurement.
 
+#if defined(RENDERER_SIGTERM_HANDLER)
+    AddSigtermHandler();
+#endif
+
     if (run_loop) {
 #if defined(OS_MACOSX)
       if (pool)
         pool->Recycle();
 #endif
       TRACE_EVENT_BEGIN_ETW("RendererMain.START_MSG_LOOP", 0, 0);
       MessageLoop::current()->Run();
       TRACE_EVENT_END_ETW("RendererMain.START_MSG_LOOP", 0, 0);
     }
   }
   platform.PlatformUninitialize();
   TRACE_EVENT_END_ETW("RendererMain", 0, "");
   return 0;
 }