package log import ( "io" "log" "os" "time" "v2ray.com/core/common/platform" "v2ray.com/core/common/signal/done" "v2ray.com/core/common/signal/semaphore" ) // Writer is the interface for writing logs. type Writer interface { Write(string) error io.Closer } // WriterCreator is a function to create LogWriters. type WriterCreator func() Writer type generalLogger struct { creator WriterCreator buffer chan Message access *semaphore.Instance done *done.Instance } // NewLogger returns a generic log handler that can handle all type of messages. func NewLogger(logWriterCreator WriterCreator) Handler { return &generalLogger{ creator: logWriterCreator, buffer: make(chan Message, 16), access: semaphore.New(1), done: done.New(), } } func (l *generalLogger) run() { defer l.access.Signal() dataWritten := false ticker := time.NewTicker(time.Minute) defer ticker.Stop() logger := l.creator() if logger == nil { return } defer logger.Close() for { select { case <-l.done.Wait(): return case msg := <-l.buffer: logger.Write(msg.String() + platform.LineSeparator()) dataWritten = true case <-ticker.C: if !dataWritten { return } dataWritten = false } } } func (l *generalLogger) Handle(msg Message) { select { case l.buffer <- msg: default: } select { case <-l.access.Wait(): go l.run() default: } } func (l *generalLogger) Close() error { return l.done.Close() } type consoleLogWriter struct { logger *log.Logger } func (w *consoleLogWriter) Write(s string) error { w.logger.Print(s) return nil } func (w *consoleLogWriter) Close() error { return nil } type fileLogWriter struct { file *os.File logger *log.Logger } func (w *fileLogWriter) Write(s string) error { w.logger.Print(s) return nil } func (w *fileLogWriter) Close() error { return w.file.Close() } // CreateStdoutLogWriter returns a LogWriterCreator that creates LogWriter for stdout. func CreateStdoutLogWriter() WriterCreator { return func() Writer { return &consoleLogWriter{ logger: log.New(os.Stdout, "", log.Ldate|log.Ltime), } } } // CreateStderrLogWriter returns a LogWriterCreator that creates LogWriter for stderr. func CreateStderrLogWriter() WriterCreator { return func() Writer { return &consoleLogWriter{ logger: log.New(os.Stderr, "", log.Ldate|log.Ltime), } } } // CreateFileLogWriter returns a LogWriterCreator that creates LogWriter for the given file. func CreateFileLogWriter(path string) (WriterCreator, error) { file, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600) if err != nil { return nil, err } file.Close() return func() Writer { file, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600) if err != nil { return nil } return &fileLogWriter{ file: file, logger: log.New(file, "", log.Ldate|log.Ltime), } }, nil } func init() { RegisterHandler(NewLogger(CreateStdoutLogWriter())) }