From 7df612f527bd5dc2e785bf766d7d61124c260b94 Mon Sep 17 00:00:00 2001 From: Paul Buetow Date: Mon, 16 Nov 2020 22:11:44 +0000 Subject: remove drun command for simplicity. only focus on interactive commands dealing with log streams --- internal/io/run/run.go | 150 ------------------------------------------------- 1 file changed, 150 deletions(-) delete mode 100644 internal/io/run/run.go (limited to 'internal/io') diff --git a/internal/io/run/run.go b/internal/io/run/run.go deleted file mode 100644 index 2bb3756..0000000 --- a/internal/io/run/run.go +++ /dev/null @@ -1,150 +0,0 @@ -package run - -import ( - "bufio" - "context" - "io" - "os/exec" - "sync" - "syscall" - "time" - - "github.com/mimecast/dtail/internal/io/line" - "github.com/mimecast/dtail/internal/io/logger" -) - -// Run is for execute a command. -type Run struct { - command string - args []string - cmd *exec.Cmd - pgroupKilled chan struct{} -} - -// New returns a new command runner. -func New(command string, args []string) Run { - return Run{ - command: command, - args: args, - pgroupKilled: make(chan struct{}), - } -} - -// StartBackground starts running the command in background. -func (r Run) StartBackground(ctx context.Context, wg *sync.WaitGroup, ec chan<- int, lines chan<- line.Line) (pid int, err error) { - pid = -1 - - if len(r.args) > 0 { - logger.Debug(r.command, r.args, " ") - r.cmd = exec.CommandContext(ctx, r.command, r.args...) - } else { - logger.Debug(r.command) - r.cmd = exec.CommandContext(ctx, r.command) - } - - // Create a new process group, so that kill() will only kill this command + pgroup. - r.cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} - - stdoutPipe, myErr := r.cmd.StdoutPipe() - if err != nil { - wg.Done() - err = myErr - return - } - - stderrPipe, myErr := r.cmd.StderrPipe() - if myErr != nil { - wg.Done() - err = myErr - return - } - - if myErr := r.cmd.Start(); err != nil { - wg.Done() - err = myErr - return - } - - if r.cmd.Process != nil { - pid = r.cmd.Process.Pid - } - - commandExited := make(chan struct{}) - - var pipeWg sync.WaitGroup - pipeWg.Add(2) - - go r.killPgroup(ctx, commandExited, pid) - go r.pipeToLines(commandExited, &pipeWg, pid, stdoutPipe, "STDOUT", lines) - go r.pipeToLines(commandExited, &pipeWg, pid, stderrPipe, "STDERR", lines) - - go func() { - exitCode := 255 - if waitErr := r.cmd.Wait(); waitErr != nil { - if exitError, ok := waitErr.(*exec.ExitError); ok { - exitCode = exitError.ExitCode() - } - } - ec <- exitCode - - // Tell pipes we are done - close(commandExited) - // Wait for process group to be killed - <-r.pgroupKilled - // Wait for the pipes to flush the contents - pipeWg.Wait() - // Now the job is truly done - wg.Done() - }() - - return -} - -func (r Run) pipeToLines(commandExited chan struct{}, wg *sync.WaitGroup, pid int, reader io.Reader, what string, lines chan<- line.Line) { - defer wg.Done() - bufReader := bufio.NewReader(reader) - - for { - time.Sleep(time.Millisecond * 10) - lineStr, err := bufReader.ReadString('\n') - - if err != nil { - select { - case <-commandExited: - return - default: - } - continue - } - - newLine := line.Line{ - Content: []byte(lineStr), - Count: uint64(pid), - TransmittedPerc: 100, - SourceID: what, - } - - select { - case lines <- newLine: - case <-commandExited: - return - } - } -} - -func (r Run) killPgroup(ctx context.Context, commandExited chan struct{}, pid int) { - if pid == -1 { - close(r.pgroupKilled) - return - } - - if pgid, err := syscall.Getpgid(pid); err == nil { - // Kill process group when done - select { - case <-ctx.Done(): - case <-commandExited: - } - syscall.Kill(-pgid, syscall.SIGKILL) - close(r.pgroupKilled) - } -} -- cgit v1.2.3