blob: d005df559c821a80074b935dc0dd2655047a44e7 [file] [log] [blame]
// 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.
#ifndef TOOLS_GN_SCHEDULER_H_
#define TOOLS_GN_SCHEDULER_H_
#include <condition_variable>
#include <map>
#include <mutex>
#include "base/atomic_ref_count.h"
#include "base/files/file_path.h"
#include "base/macros.h"
#include "tools/gn/input_file_manager.h"
#include "tools/gn/label.h"
#include "tools/gn/source_file.h"
#include "tools/gn/token.h"
#include "util/msg_loop.h"
#include "util/task.h"
#include "util/worker_pool.h"
class Target;
// Maintains the thread pool and error state.
class Scheduler {
public:
Scheduler();
~Scheduler();
bool Run();
MsgLoop* task_runner() {
DCHECK(main_thread_run_loop_);
return main_thread_run_loop_;
}
InputFileManager* input_file_manager() { return input_file_manager_.get(); }
bool verbose_logging() const { return verbose_logging_; }
void set_verbose_logging(bool v) { verbose_logging_ = v; }
// TODO(brettw) data race on this access (benign?).
bool is_failed() const { return is_failed_; }
void Log(const std::string& verb, const std::string& msg);
void FailWithError(const Err& err);
void ScheduleWork(Task work);
void Shutdown();
// Declares that the given file was read and affected the build output.
//
// Some consumers expect provided path to be absolute.kk
//
// TODO(brettw) this is global rather than per-BuildSettings. If we
// start using >1 build settings, then we probably want this to take a
// BuildSettings object so we know the depdency on a per-build basis.
// If moved, most of the Add/Get functions below should move as well.
void AddGenDependency(const base::FilePath& file);
std::vector<base::FilePath> GetGenDependencies() const;
// Tracks calls to write_file for resolving with the unknown generated
// inputs (see AddUnknownGeneratedInput below).
void AddWrittenFile(const SourceFile& file);
// Schedules a file to be written due to a target setting write_runtime_deps.
void AddWriteRuntimeDepsTarget(const Target* entry);
std::vector<const Target*> GetWriteRuntimeDepsTargets() const;
bool IsFileGeneratedByWriteRuntimeDeps(const OutputFile& file) const;
// Tracks generated_file calls.
void AddGeneratedFile(const SourceFile& entry);
bool IsFileGeneratedByTarget(const SourceFile& file) const;
// Unknown generated inputs are files that a target declares as an input
// in the output directory, but which aren't generated by any dependency.
//
// Some of these files will be files written by write_file and will be
// GenDependencies (see AddWrittenFile above). There are OK and include
// things like response files for scripts. Others cases will be ones where
// the file is generated by a target that's not a dependency.
//
// In order to distinguish these two cases, the checking for these input
// files needs to be done after all targets are complete. This also has the
// nice side effect that if a target generates the file we can find it and
// tell the user which dependency is missing.
//
// The result returned by GetUnknownGeneratedInputs will not count any files
// that were written by write_file during execution.
void AddUnknownGeneratedInput(const Target* target, const SourceFile& file);
std::multimap<SourceFile, const Target*> GetUnknownGeneratedInputs() const;
void ClearUnknownGeneratedInputsAndWrittenFiles(); // For testing.
// We maintain a count of the things we need to do that works like a
// refcount. When this reaches 0, the program exits.
void IncrementWorkCount();
void DecrementWorkCount();
void SuppressOutputForTesting(bool suppress);
private:
void LogOnMainThread(const std::string& verb, const std::string& msg);
void FailWithErrorOnMainThread(const Err& err);
void DoTargetFileWrite(const Target* target);
void OnComplete();
// Waits for tasks scheduled via ScheduleWork() to complete their execution.
void WaitForPoolTasks();
MsgLoop* main_thread_run_loop_;
scoped_refptr<InputFileManager> input_file_manager_;
bool verbose_logging_ = false;
base::AtomicRefCount work_count_;
// Number of tasks scheduled by ScheduleWork() that haven't completed their
// execution.
base::AtomicRefCount pool_work_count_;
// Lock for |pool_work_count_cv_|.
std::mutex pool_work_count_lock_;
// Condition variable signaled when |pool_work_count_| reaches zero.
std::condition_variable pool_work_count_cv_;
WorkerPool worker_pool_;
mutable std::mutex lock_;
bool is_failed_ = false;
bool suppress_output_for_testing_ = false;
// Used to track whether the worker pool has been shutdown. This is necessary
// to clean up after tests that make a scheduler but don't run the message
// loop.
bool has_been_shutdown_ = false;
// Protected by the lock. See the corresponding Add/Get functions above.
std::vector<base::FilePath> gen_dependencies_;
std::vector<SourceFile> written_files_;
std::vector<const Target*> write_runtime_deps_targets_;
std::multimap<SourceFile, const Target*> unknown_generated_inputs_;
std::map<SourceFile, bool> generated_files_;
DISALLOW_COPY_AND_ASSIGN(Scheduler);
};
extern Scheduler* g_scheduler;
#endif // TOOLS_GN_SCHEDULER_H_