Browse code
Move signal handling code to pkg/signal.Trap
Signed-off-by: Solomon Hykes <solomon@docker.com>
Solomon Hykes authored on 2014/08/06 01:32:24Showing 2 changed files
| 1 | 1 |
new file mode 100644 |
| ... | ... |
@@ -0,0 +1,53 @@ |
| 0 |
+package signal |
|
| 1 |
+ |
|
| 2 |
+import ( |
|
| 3 |
+ "log" |
|
| 4 |
+ "os" |
|
| 5 |
+ gosignal "os/signal" |
|
| 6 |
+ "sync/atomic" |
|
| 7 |
+ "syscall" |
|
| 8 |
+) |
|
| 9 |
+ |
|
| 10 |
+// Trap sets up a simplified signal "trap", appropriate for common |
|
| 11 |
+// behavior expected from a vanilla unix command-line tool in general |
|
| 12 |
+// (and the Docker engine in particular). |
|
| 13 |
+// |
|
| 14 |
+// * If SIGINT or SIGTERM are received, `cleanup` is called, then the process is terminated. |
|
| 15 |
+// * If SIGINT or SIGTERM are repeated 3 times before cleanup is complete, then cleanup is |
|
| 16 |
+// skipped and the process terminated directly. |
|
| 17 |
+// * If "DEBUG" is set in the environment, SIGQUIT causes an exit without cleanup. |
|
| 18 |
+// |
|
| 19 |
+func Trap(cleanup func()) {
|
|
| 20 |
+ c := make(chan os.Signal, 1) |
|
| 21 |
+ signals := []os.Signal{os.Interrupt, syscall.SIGTERM}
|
|
| 22 |
+ if os.Getenv("DEBUG") == "" {
|
|
| 23 |
+ signals = append(signals, syscall.SIGQUIT) |
|
| 24 |
+ } |
|
| 25 |
+ gosignal.Notify(c, signals...) |
|
| 26 |
+ go func() {
|
|
| 27 |
+ interruptCount := uint32(0) |
|
| 28 |
+ for sig := range c {
|
|
| 29 |
+ go func(sig os.Signal) {
|
|
| 30 |
+ log.Printf("Received signal '%v', starting shutdown of docker...\n", sig)
|
|
| 31 |
+ switch sig {
|
|
| 32 |
+ case os.Interrupt, syscall.SIGTERM: |
|
| 33 |
+ // If the user really wants to interrupt, let him do so. |
|
| 34 |
+ if atomic.LoadUint32(&interruptCount) < 3 {
|
|
| 35 |
+ atomic.AddUint32(&interruptCount, 1) |
|
| 36 |
+ // Initiate the cleanup only once |
|
| 37 |
+ if atomic.LoadUint32(&interruptCount) == 1 {
|
|
| 38 |
+ // Call cleanup handler |
|
| 39 |
+ cleanup() |
|
| 40 |
+ } else {
|
|
| 41 |
+ return |
|
| 42 |
+ } |
|
| 43 |
+ } else {
|
|
| 44 |
+ log.Printf("Force shutdown of docker, interrupting cleanup\n")
|
|
| 45 |
+ } |
|
| 46 |
+ case syscall.SIGQUIT: |
|
| 47 |
+ } |
|
| 48 |
+ os.Exit(128 + int(sig.(syscall.Signal))) |
|
| 49 |
+ }(sig) |
|
| 50 |
+ } |
|
| 51 |
+ }() |
|
| 52 |
+} |
| ... | ... |
@@ -6,15 +6,11 @@ package server |
| 6 | 6 |
|
| 7 | 7 |
import ( |
| 8 | 8 |
"fmt" |
| 9 |
- "log" |
|
| 10 |
- "os" |
|
| 11 |
- gosignal "os/signal" |
|
| 12 |
- "sync/atomic" |
|
| 13 |
- "syscall" |
|
| 14 | 9 |
|
| 15 | 10 |
"github.com/docker/docker/daemon" |
| 16 | 11 |
"github.com/docker/docker/daemonconfig" |
| 17 | 12 |
"github.com/docker/docker/engine" |
| 13 |
+ "github.com/docker/docker/pkg/signal" |
|
| 18 | 14 |
"github.com/docker/docker/utils" |
| 19 | 15 |
) |
| 20 | 16 |
|
| ... | ... |
@@ -50,38 +46,10 @@ func InitServer(job *engine.Job) engine.Status {
|
| 50 | 50 |
return job.Error(err) |
| 51 | 51 |
} |
| 52 | 52 |
job.Logf("Setting up signal traps")
|
| 53 |
- c := make(chan os.Signal, 1) |
|
| 54 |
- signals := []os.Signal{os.Interrupt, syscall.SIGTERM}
|
|
| 55 |
- if os.Getenv("DEBUG") == "" {
|
|
| 56 |
- signals = append(signals, syscall.SIGQUIT) |
|
| 57 |
- } |
|
| 58 |
- gosignal.Notify(c, signals...) |
|
| 59 |
- go func() {
|
|
| 60 |
- interruptCount := uint32(0) |
|
| 61 |
- for sig := range c {
|
|
| 62 |
- go func(sig os.Signal) {
|
|
| 63 |
- log.Printf("Received signal '%v', starting shutdown of docker...\n", sig)
|
|
| 64 |
- switch sig {
|
|
| 65 |
- case os.Interrupt, syscall.SIGTERM: |
|
| 66 |
- // If the user really wants to interrupt, let him do so. |
|
| 67 |
- if atomic.LoadUint32(&interruptCount) < 3 {
|
|
| 68 |
- atomic.AddUint32(&interruptCount, 1) |
|
| 69 |
- // Initiate the cleanup only once |
|
| 70 |
- if atomic.LoadUint32(&interruptCount) == 1 {
|
|
| 71 |
- utils.RemovePidFile(srv.daemon.Config().Pidfile) |
|
| 72 |
- srv.Close() |
|
| 73 |
- } else {
|
|
| 74 |
- return |
|
| 75 |
- } |
|
| 76 |
- } else {
|
|
| 77 |
- log.Printf("Force shutdown of docker, interrupting cleanup\n")
|
|
| 78 |
- } |
|
| 79 |
- case syscall.SIGQUIT: |
|
| 80 |
- } |
|
| 81 |
- os.Exit(128 + int(sig.(syscall.Signal))) |
|
| 82 |
- }(sig) |
|
| 83 |
- } |
|
| 84 |
- }() |
|
| 53 |
+ signal.Trap(func() {
|
|
| 54 |
+ utils.RemovePidFile(srv.daemon.Config().Pidfile) |
|
| 55 |
+ srv.Close() |
|
| 56 |
+ }) |
|
| 85 | 57 |
job.Eng.Hack_SetGlobalVar("httpapi.server", srv)
|
| 86 | 58 |
job.Eng.Hack_SetGlobalVar("httpapi.daemon", srv.daemon)
|
| 87 | 59 |
|