Makes wait-for-debugger=content_browser work for mash

This changes the command line switch "n" to "process-service-name" and
makes mash-runner look for it.

BUG=none
TEST=none
R=rockot@chromium.org

Review-Url: https://codereview.chromium.org/2571603002
Cr-Commit-Position: refs/heads/master@{#437999}

chrome/app/chrome_main.cc

@@ -94,6 +94,7 @@ int ChromeMain(int argc, const char** argv) {
         *base::CommandLine::ForCurrentProcess();
     if (command_line.HasSwitch("mash"))
       return MashMain();
+    WaitForMashDebuggerIfNecessary();
   }
 #endif  // BUILDFLAG(ENABLE_PACKAGE_MASH_SERVICES)
 

chrome/app/mash/mash_runner.cc

@@ -6,6 +6,7 @@
 
 #include "base/at_exit.h"
 #include "base/base_paths.h"
+#include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/debugger.h"
@@ -16,6 +17,7 @@
 #include "base/message_loop/message_loop.h"
 #include "base/path_service.h"
 #include "base/process/launch.h"
+#include "base/process/process.h"
 #include "base/run_loop.h"
 #include "base/task_scheduler/task_scheduler.h"
 #include "base/threading/sequenced_worker_pool.h"
@@ -36,6 +38,7 @@
 #include "services/service_manager/public/cpp/service_context.h"
 #include "services/service_manager/public/cpp/standalone_service/standalone_service.h"
 #include "services/service_manager/public/interfaces/service_factory.mojom.h"
+#include "services/service_manager/runner/common/client_util.h"
 #include "services/service_manager/runner/common/switches.h"
 #include "services/service_manager/runner/init.h"
 #include "services/service_manager/standalone/context.h"
@@ -242,3 +245,23 @@ int MashMain() {
   MashRunner mash_runner;
   return mash_runner.Run();
 }
+
+void WaitForMashDebuggerIfNecessary() {
+  if (!service_manager::ServiceManagerIsRemote())
+    return;
+
+  const base::CommandLine* command_line =
+      base::CommandLine::ForCurrentProcess();
+  const std::string service_name =
+      command_line->GetSwitchValueASCII(switches::kProcessServiceName);
+  if (service_name !=
+      command_line->GetSwitchValueASCII(switches::kWaitForDebugger)) {
+    return;
+  }
+
+  // Include the pid as logging may not have been initialized yet (the pid
+  // printed out by logging is wrong).
+  LOG(WARNING) << "waiting for debugger to attach for service " << service_name
+               << " pid=" << base::Process::Current().Pid();
+  base::debug::WaitForDebugger(120, true);
+}

chrome/app/mash/mash_runner.h

@@ -40,4 +40,8 @@ class MashRunner {
 
 int MashMain();
 
+// Called if the command line isn't mash to potentially wait for a debugger
+// to attach.
+void WaitForMashDebuggerIfNecessary();
+
 #endif  // CHROME_APP_MASH_MASH_RUNNER_H_

services/service_manager/runner/common/switches.cc

@@ -18,6 +18,9 @@ const char kEnableSandbox[] = "enable-sandbox";
 // primordial message pipe to the parent.
 const char kPrimordialPipeToken[] = "primordial-pipe-token";
 
+// The name of the service the process is starting for.
+const char kProcessServiceName[] = "process-service-name";
+
 // Specifies a JSON file from which to read a set of service metadata overrides.
 // This can be used with the standalone mojo_runner to override executable and
 // package resolution behavior.

services/service_manager/runner/common/switches.h

@@ -12,6 +12,7 @@ namespace switches {
 extern const char kChildProcess[];
 extern const char kEnableSandbox[];
 extern const char kPrimordialPipeToken[];
+extern const char kProcessServiceName[];
 extern const char kServiceOverrides[];
 
 }  // namespace switches

services/service_manager/runner/host/child_process_host.cc

@@ -81,8 +81,9 @@ mojom::ServicePtr ChildProcessHost::Start(
 
   child_command_line->AppendArguments(parent_command_line, false);
 
+  child_command_line->AppendSwitchASCII(::switches::kProcessServiceName,
+                                        target.name());
 #ifndef NDEBUG
-  child_command_line->AppendSwitchASCII("n", target.name());
   child_command_line->AppendSwitchASCII("u", target.user_id());
 #endif