Basic process manager

modules/process/manager.go

@@ -0,0 +1,89 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package process
+
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"time"
+
+	"github.com/gogits/gogs/modules/log"
+)
+
+// Process represents a working process inherit from Gogs.
+type Process struct {
+	Pid         int64 // Process ID, not system one.
+	Description string
+	Start       time.Time
+	Cmd         *exec.Cmd
+}
+
+// List of existing processes.
+var (
+	curPid    int64 = 1
+	Processes []*Process
+)
+
+// Add adds a existing process and returns its PID.
+func Add(desc string, cmd *exec.Cmd) int64 {
+	pid := curPid
+	Processes = append(Processes, &Process{
+		Pid:         pid,
+		Description: desc,
+		Start:       time.Now(),
+		Cmd:         cmd,
+	})
+	curPid++
+	return pid
+}
+
+func ExecDir(dir, desc, cmdName string, args ...string) (string, string, error) {
+	bufOut := new(bytes.Buffer)
+	bufErr := new(bytes.Buffer)
+
+	cmd := exec.Command(cmdName, args...)
+	cmd.Dir = dir
+	cmd.Stdout = bufOut
+	cmd.Stderr = bufErr
+
+	pid := Add(desc, cmd)
+	err := cmd.Run()
+	if errKill := Kill(pid); errKill != nil {
+		log.Error("Exec: %v", pid, desc, errKill)
+	}
+	return bufOut.String(), bufErr.String(), err
+}
+
+// Exec starts executing a command and record its process.
+func Exec(desc, cmdName string, args ...string) (string, string, error) {
+	return ExecDir("", desc, cmdName, args...)
+}
+
+// Remove removes a process from list.
+func Remove(pid int64) {
+	for i, proc := range Processes {
+		if proc.Pid == pid {
+			Processes = append(Processes[:i], Processes[i+1:]...)
+			return
+		}
+	}
+}
+
+// Kill kills and removes a process from list.
+func Kill(pid int64) error {
+	for i, proc := range Processes {
+		if proc.Pid == pid {
+			if proc.Cmd.Process != nil && proc.Cmd.ProcessState != nil && !proc.Cmd.ProcessState.Exited() {
+				if err := proc.Cmd.Process.Kill(); err != nil {
+					return fmt.Errorf("fail to kill process(%d/%s): %v", proc.Pid, proc.Description, err)
+				}
+			}
+			Processes = append(Processes[:i], Processes[i+1:]...)
+			return nil
+		}
+	}
+	return nil
+}