POSIX: don't spawn zombies.

chrome/browser/browser_main.cc

 // Copyright (c) 2006-2008 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 "build/build_config.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/field_trial.h"
@@ skipping 38 matching lines @@
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 #include "grit/net_resources.h"
 #include "net/base/net_module.h"
 #include "net/http/http_network_session.h"
 
 #if defined(OS_POSIX)
 // TODO(port): get rid of this include. It's used just to provide declarations
 // and stub definitions for classes we encouter during the porting effort.
 #include "chrome/common/temp_scaffolding_stubs.h"
+#include <signal.h>
 #endif
 
 // TODO(port): several win-only methods have been pulled out of this, but
 // BrowserMain() as a whole needs to be broken apart so that it's usable by
 // other platforms. For now, it's just a stub. This is a serious work in
 // progress and should not be taken as an indication of a real refactoring.
 
 #if defined(OS_WIN)
 
 #include <windows.h>
@@ skipping 104 matching lines @@
 }
 
 void RunUIMessageLoop(BrowserProcess* browser_process) {
 #if defined(OS_WIN)
   MessageLoopForUI::current()->Run(browser_process->accelerator_handler());
 #elif defined(OS_POSIX)
   MessageLoopForUI::current()->Run();
 #endif
 }
 
+#if defined(OS_POSIX)
+// See comment below, where sigaction is called.
+void SIGCHLDHandler(int signal) {
+}
+#endif
+
 }  // namespace
 
 // Main routine for running as the Browser process.
 int BrowserMain(const MainFunctionParams& parameters) {
   const CommandLine& parsed_command_line = parameters.command_line_;
   base::ScopedNSAutoreleasePool* pool = parameters.autorelease_pool_;
 
   // WARNING: If we get a WM_ENDSESSION objects created on the stack here
   // are NOT deleted. If you need something to run during WM_ENDSESSION add it
   // to browser_shutdown::Shutdown or BrowserProcess::EndSession.
 
   // TODO(beng, brettw): someday, break this out into sub functions with well
   //                     defined roles (e.g. pre/post-profile startup, etc).
 
 #ifdef TRACK_ALL_TASK_OBJECTS
   // Start tracking the creation and deletion of Task instance.
   // This construction MUST be done before main_message_loop, so that it is
   // destroyed after the main_message_loop.
   tracked_objects::AutoTracking tracking_objects;
 #endif
 
+#if defined(OS_POSIX)
+  // We need to accept SIGCHLD, even though our handler is a no-op because
+  // otherwise we cannot wait on children. (According to POSIX 2001.)
+  struct sigaction action = {0};
+  action.sa_handler = SIGCHLDHandler;
+  CHECK(sigaction(SIGCHLD, &action, NULL) == 0);
+#endif
+
   // Do platform-specific things (such as finishing initializing Cocoa)
   // prior to instantiating the message loop. This could be turned into a
   // broadcast notification.
   Platform::WillInitializeMainMessageLoop(parsed_command_line);
 
   MessageLoop main_message_loop(MessageLoop::TYPE_UI);
 
   // Initialize the SystemMonitor
   base::SystemMonitor::Start();
 
@@ skipping 400 matching lines @@
   if (metrics)
     metrics->Stop();
 
   // browser_shutdown takes care of deleting browser_process, so we need to
   // release it.
   browser_process.release();
   browser_shutdown::Shutdown();
 
   return result_code;
 }