From 04f0d148e9946d4ec20d8d8a521560b091877665 Mon Sep 17 00:00:00 2001
From: Alex Brainman <alex.brainman@gmail.com>
Date: Fri, 14 Dec 2012 17:33:59 +1100
Subject: [PATCH] cmd/go: handle os signals

Ignore signals during "go run" and wait for running child
process to exit. Stop executing further tests during "go test",
wait for running tests to exit and report error exit code.

Original CL 6351053 by dfc.

Fixes #3572.
Fixes #3581.

R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/6903061
---
 src/cmd/dist/build.c         |  1 +
 src/cmd/go/build.go          | 31 +++++++++++++++++++++----------
 src/cmd/go/run.go            |  1 +
 src/cmd/go/signal.go         | 31 +++++++++++++++++++++++++++++++
 src/cmd/go/signal_notunix.go | 13 +++++++++++++
 src/cmd/go/signal_unix.go    | 14 ++++++++++++++
 src/cmd/go/test.go           |  1 +
 7 files changed, 82 insertions(+), 10 deletions(-)
 create mode 100644 src/cmd/go/signal.go
 create mode 100644 src/cmd/go/signal_notunix.go
 create mode 100644 src/cmd/go/signal_unix.go

diff --git a/src/cmd/dist/build.c b/src/cmd/dist/build.c
index fca668ceb8..13dbe0e81d 100644
--- a/src/cmd/dist/build.c
+++ b/src/cmd/dist/build.c
@@ -1183,6 +1183,7 @@ static char *buildorder[] = {
 	"pkg/go/ast",
 	"pkg/go/parser",
 	"pkg/os/exec",
+	"pkg/os/signal",
 	"pkg/net/url",
 	"pkg/text/template/parse",
 	"pkg/text/template",
diff --git a/src/cmd/go/build.go b/src/cmd/go/build.go
index 7e3d2f496d..5f91227f15 100644
--- a/src/cmd/go/build.go
+++ b/src/cmd/go/build.go
@@ -548,7 +548,6 @@ func (b *builder) do(root *action) {
 	}
 
 	b.readySema = make(chan bool, len(all))
-	done := make(chan bool)
 
 	// Initialize per-action execution state.
 	for _, a := range all {
@@ -596,10 +595,11 @@ func (b *builder) do(root *action) {
 
 		if a == root {
 			close(b.readySema)
-			done <- true
 		}
 	}
 
+	var wg sync.WaitGroup
+
 	// Kick off goroutines according to parallelism.
 	// If we are using the -n flag (just printing commands)
 	// drop the parallelism to 1, both to make the output
@@ -609,19 +609,30 @@ func (b *builder) do(root *action) {
 		par = 1
 	}
 	for i := 0; i < par; i++ {
+		wg.Add(1)
 		go func() {
-			for _ = range b.readySema {
-				// Receiving a value from b.sema entitles
-				// us to take from the ready queue.
-				b.exec.Lock()
-				a := b.ready.pop()
-				b.exec.Unlock()
-				handle(a)
+			defer wg.Done()
+			for {
+				select {
+				case _, ok := <-b.readySema:
+					if !ok {
+						return
+					}
+					// Receiving a value from b.readySema entitles
+					// us to take from the ready queue.
+					b.exec.Lock()
+					a := b.ready.pop()
+					b.exec.Unlock()
+					handle(a)
+				case <-interrupted:
+					setExitStatus(1)
+					return
+				}
 			}
 		}()
 	}
 
-	<-done
+	wg.Wait()
 }
 
 // build is the action for building a single package or command.
diff --git a/src/cmd/go/run.go b/src/cmd/go/run.go
index 0f41fa61be..88f57617e4 100644
--- a/src/cmd/go/run.go
+++ b/src/cmd/go/run.go
@@ -84,6 +84,7 @@ func runStdin(cmdargs ...interface{}) {
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
+	startSigHandlers()
 	if err := cmd.Run(); err != nil {
 		errorf("%v", err)
 	}
diff --git a/src/cmd/go/signal.go b/src/cmd/go/signal.go
new file mode 100644
index 0000000000..e8ba0d3655
--- /dev/null
+++ b/src/cmd/go/signal.go
@@ -0,0 +1,31 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"os"
+	"os/signal"
+	"sync"
+)
+
+// interrupted is closed, if go process is interrupted.
+var interrupted = make(chan struct{})
+
+// processSignals setups signal handler.
+func processSignals() {
+	sig := make(chan os.Signal)
+	signal.Notify(sig, signalsToIgnore...)
+	go func() {
+		<-sig
+		close(interrupted)
+	}()
+}
+
+var onceProcessSignals sync.Once
+
+// startSigHandlers start signal handlers.
+func startSigHandlers() {
+	onceProcessSignals.Do(processSignals)
+}
diff --git a/src/cmd/go/signal_notunix.go b/src/cmd/go/signal_notunix.go
new file mode 100644
index 0000000000..ef13c19195
--- /dev/null
+++ b/src/cmd/go/signal_notunix.go
@@ -0,0 +1,13 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build plan9 windows
+
+package main
+
+import (
+	"os"
+)
+
+var signalsToIgnore = []os.Signal{os.Interrupt}
diff --git a/src/cmd/go/signal_unix.go b/src/cmd/go/signal_unix.go
new file mode 100644
index 0000000000..489a73b83b
--- /dev/null
+++ b/src/cmd/go/signal_unix.go
@@ -0,0 +1,14 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin freebsd linux netbsd openbsd
+
+package main
+
+import (
+	"os"
+	"syscall"
+)
+
+var signalsToIgnore = []os.Signal{os.Interrupt, syscall.SIGQUIT}
diff --git a/src/cmd/go/test.go b/src/cmd/go/test.go
index efd14609aa..555c6f50ed 100644
--- a/src/cmd/go/test.go
+++ b/src/cmd/go/test.go
@@ -644,6 +644,7 @@ func (b *builder) runTest(a *action) error {
 	// running.
 	tick := time.NewTimer(testKillTimeout)
 	if err == nil {
+		startSigHandlers()
 		done := make(chan error)
 		go func() {
 			done <- cmd.Wait()
-- 
2.48.1