[tor-commits] [meek/master] Update client shutdown procedure.

[dcf at torproject.org]

commit 0ec986eb2b4bc23d81e6e8beffd382890f55bfb1
Author: David Fifield <david at bamsoftware.com>
Date:   Thu Jun 29 16:43:01 2017 -0700

    Update client shutdown procedure.
    
    Ignore SIGINT, handle TOR_PT_EXIT_ON_STDIN_CLOSE.
---
 meek-client-torbrowser/meek-client-torbrowser.go |  2 +-
 meek-client/meek-client.go                       | 34 +++++++++++++-----------
 2 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/meek-client-torbrowser/meek-client-torbrowser.go b/meek-client-torbrowser/meek-client-torbrowser.go
index cbbf9ca..691a566 100644
--- a/meek-client-torbrowser/meek-client-torbrowser.go
+++ b/meek-client-torbrowser/meek-client-torbrowser.go
@@ -308,7 +308,7 @@ func main() {
 	signal.Notify(make(chan os.Signal, 1), syscall.SIGPIPE)
 
 	sigChan := make(chan os.Signal, 1)
-	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+	signal.Notify(sigChan, syscall.SIGTERM)
 
 	// Unset environment variables that Firefox sets after a restart (as
 	// caused by, for example, an update or the installation of an add-on).
diff --git a/meek-client/meek-client.go b/meek-client/meek-client.go
index c3eadc4..9a818d0 100644
--- a/meek-client/meek-client.go
+++ b/meek-client/meek-client.go
@@ -36,6 +36,7 @@ import (
 	"flag"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"log"
 	"net"
 	"net/http"
@@ -441,9 +442,19 @@ func main() {
 	var numHandlers int = 0
 	var sig os.Signal
 	sigChan := make(chan os.Signal, 1)
-	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+	signal.Notify(sigChan, syscall.SIGTERM)
 
-	// Wait for first signal.
+	if os.Getenv("TOR_PT_EXIT_ON_STDIN_CLOSE") == "1" {
+		// This environment variable means we should treat EOF on stdin
+		// just like SIGTERM: https://bugs.torproject.org/15435.
+		go func() {
+			io.Copy(ioutil.Discard, os.Stdin)
+			log.Printf("synthesizing SIGTERM because of stdin close")
+			sigChan <- syscall.SIGTERM
+		}()
+	}
+
+	// Keep track of handlers and wait for a signal.
 	sig = nil
 	for sig == nil {
 		select {
@@ -453,23 +464,14 @@ func main() {
 			log.Printf("got signal %s", sig)
 		}
 	}
+
 	for _, ln := range listeners {
 		ln.Close()
 	}
-
-	if sig == syscall.SIGTERM {
-		log.Printf("done")
-		return
-	}
-
-	// Wait for second signal or no more handlers.
-	sig = nil
-	for sig == nil && numHandlers != 0 {
-		select {
-		case n := <-handlerChan:
-			numHandlers += n
-		case sig = <-sigChan:
-			log.Printf("got second signal %s", sig)
+	for n := range handlerChan {
+		numHandlers += n
+		if numHandlers == 0 {
+			break
 		}
 	}