syz-ci: add continuous integration system

1 files changed, 120 insertions, 0 deletions

diff --git a/syz-ci/managercmd.go b/syz-ci/managercmd.go
new file mode 100644
index 000000000..2f495b73f
--- /dev/null
+++ b/syz-ci/managercmd.go
@@ -0,0 +1,120 @@
+// Copyright 2017 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package main
+
+import (
+	"os"
+	"os/exec"
+	"syscall"
+	"time"
+
+	. "github.com/google/syzkaller/pkg/log"
+)
+
+// ManagerCmd encapsulates a single instance of syz-manager process.
+// It automatically restarts syz-manager if it exits unexpectedly,
+// and supports graceful shutdown via SIGINT.
+type ManagerCmd struct {
+	name    string
+	log     string
+	bin     string
+	args    []string
+	closing chan bool
+}
+
+// NewManagerCmd starts new syz-manager process.
+// name - name for logging.
+// log - manager log file with stdout/stderr.
+// bin/args - process binary/args.
+func NewManagerCmd(name, log, bin string, args ...string) *ManagerCmd {
+	mc := &ManagerCmd{
+		name:    name,
+		log:     log,
+		bin:     bin,
+		args:    args,
+		closing: make(chan bool),
+	}
+	go mc.loop()
+	return mc
+}
+
+// Close gracefully shutdowns the process and waits for its termination.
+func (mc *ManagerCmd) Close() {
+	mc.closing <- true
+	<-mc.closing
+}
+
+func (mc *ManagerCmd) loop() {
+	const (
+		restartPeriod    = time.Minute // don't restart crashing manager more frequently than that
+		interruptTimeout = time.Minute // give manager that much time to react to SIGINT
+	)
+	var (
+		cmd         *exec.Cmd
+		started     time.Time
+		interrupted time.Time
+		stopped     = make(chan error, 1)
+		closing     = mc.closing
+		ticker1     = time.NewTicker(restartPeriod)
+		ticker2     = time.NewTicker(interruptTimeout)
+	)
+	defer func() {
+		ticker1.Stop()
+		ticker2.Stop()
+	}()
+	for closing != nil || cmd != nil {
+		if cmd == nil {
+			// cmd is not running
+			// don't restart too frequently (in case it instantly exits with an error)
+			if time.Since(started) > restartPeriod {
+				started = time.Now()
+				logfile, err := os.Create(mc.log)
+				if err != nil {
+					Logf(1, "%v: failed to create manager log: %v", mc.name, err)
+				} else {
+					cmd = exec.Command(mc.bin, mc.args...)
+					cmd.Stdout = logfile
+					cmd.Stderr = logfile
+					err := cmd.Start()
+					logfile.Close()
+					if err != nil {
+						Logf(1, "%v: failed to start manager: %v", mc.name, err)
+						cmd = nil
+					} else {
+						Logf(1, "%v: started manager", mc.name)
+						go func() {
+							stopped <- cmd.Wait()
+						}()
+					}
+				}
+			}
+		} else {
+			// cmd is running
+			if closing == nil && time.Since(interrupted) > interruptTimeout {
+				Logf(1, "%v: killing manager", mc.name)
+				cmd.Process.Kill()
+				interrupted = time.Now()
+			}
+		}
+
+		select {
+		case <-closing:
+			closing = nil
+			if cmd != nil {
+				Logf(1, "%v: stopping manager", mc.name)
+				cmd.Process.Signal(syscall.SIGINT)
+				interrupted = time.Now()
+			}
+		case err := <-stopped:
+			if cmd == nil {
+				panic("spurious stop signal")
+			}
+			cmd = nil
+			Logf(1, "%v: manager exited with %v", mc.name, err)
+		case <-ticker1.C:
+		case <-ticker2.C:
+		}
+	}
+	close(mc.closing)
+}