GN threading refactor

tools/gn/scheduler.cc

 // Copyright (c) 2013 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 "tools/gn/scheduler.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
-#include "tools/gn/ninja_target_writer.h"
 #include "tools/gn/standard_out.h"
 
 Scheduler* g_scheduler = NULL;
 
 namespace {
 
 int GetThreadCount() {
   std::string thread_count =
       CommandLine::ForCurrentProcess()->GetSwitchValueASCII("threads");
 
   int result;
   if (thread_count.empty() || !base::StringToInt(thread_count, &result))
     return 32;
   return result;
 }
 
 }  // namespace
 
 Scheduler::Scheduler()
     : pool_(new base::SequencedWorkerPool(GetThreadCount(), "worker_")),
       input_file_manager_(new InputFileManager),
       verbose_logging_(false),
       work_count_(0),
-      is_failed_(false) {
+      is_failed_(false),
+      has_been_shutdown_(false) {
   g_scheduler = this;
 }
 
 Scheduler::~Scheduler() {
+  if (!has_been_shutdown_)
+    pool_->Shutdown();
   g_scheduler = NULL;
 }
 
 bool Scheduler::Run() {
   runner_.Run();
+  base::AutoLock lock(lock_);
   pool_->Shutdown();
+  has_been_shutdown_ = true;
   return !is_failed();
 }
 
 void Scheduler::Log(const std::string& verb, const std::string& msg) {
   if (base::MessageLoop::current() == &main_loop_) {
     LogOnMainThread(verb, msg);
   } else {
     // The run loop always joins on the sub threads, so the lifetime of this
     // object outlives the invocations of this function, hence "unretained".
     main_loop_.PostTask(FROM_HERE,
@@ skipping 24 matching lines @@
 }
 
 void Scheduler::ScheduleWork(const base::Closure& work) {
   IncrementWorkCount();
   pool_->PostWorkerTaskWithShutdownBehavior(
       FROM_HERE, base::Bind(&Scheduler::DoWork,
                             base::Unretained(this), work),
       base::SequencedWorkerPool::BLOCK_SHUTDOWN);
 }
 
-void Scheduler::ScheduleTargetFileWrite(const Target* target) {
-  pool_->PostWorkerTaskWithShutdownBehavior(
-      FROM_HERE, base::Bind(&Scheduler::DoTargetFileWrite,
-                            base::Unretained(this), target),
-      base::SequencedWorkerPool::BLOCK_SHUTDOWN);
-}
-
 void Scheduler::AddGenDependency(const base::FilePath& file) {
   base::AutoLock lock(lock_);
   gen_dependencies_.push_back(file);
 }
 
 std::vector<base::FilePath> Scheduler::GetGenDependencies() const {
   base::AutoLock lock(lock_);
   return gen_dependencies_;
 }
 
@@ skipping 17 matching lines @@
                                 const std::string& msg) {
   OutputString(verb, DECORATION_YELLOW);
   OutputString(" " + msg + "\n");
 }
 
 void Scheduler::FailWithErrorOnMainThread(const Err& err) {
   err.PrintToStdout();
   runner_.Quit();
 }
 
-void Scheduler::DoTargetFileWrite(const Target* target) {
-  NinjaTargetWriter::RunAndWriteFile(target);
-}
-
 void Scheduler::DoWork(const base::Closure& closure) {
   closure.Run();
   DecrementWorkCount();
 }
 
 void Scheduler::OnComplete() {
   // Should be called on the main thread.
   DCHECK(base::MessageLoop::current() == main_loop());
   runner_.Quit();
 }