misc/android: use adb exec-out instead of adb shell to avoid buffering

According to

https://stackoverflow.com/questions/46233200/stop-buffering-of-adb-shell-output

the adb exec-out commands avoids the buffering inherent to adb shell.

Let's see if using exec-out will fix the android builder flakyness where
exitcodes or output were sometimes missing.

Updates #30512 (perhaps fixes it).

Change-Id: Ib953ef0262b20730e0d4c332058d29c5066bfeb2
Reviewed-on: https://go-review.googlesource.com/c/164661
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

diff --git a/misc/android/go_android_exec.go b/misc/android/go_android_exec.go
index ffdacb3db8538cb376968c2d7b0e54238e1b99ed..166ced8d0f66d483613c8fd2599c2cb2b2a2c32b 100644 (file)
--- a/misc/android/go_android_exec.go
+++ b/misc/android/go_android_exec.go
@@ -75,12 +75,12 @@ func main() {
        // In case we're booting a device or emulator alongside all.bash, wait for
        // it to be ready. adb wait-for-device is not enough, we have to
        // wait for sys.boot_completed.
-       run("wait-for-device", "shell", "while [[ -z $(getprop sys.boot_completed) ]]; do sleep 1; done;")
+       run("wait-for-device", "exec-out", "while [[ -z $(getprop sys.boot_completed) ]]; do sleep 1; done;")
 
        // Prepare a temporary directory that will be cleaned up at the end.
        deviceGotmp := fmt.Sprintf("/data/local/tmp/%s-%d",
                filepath.Base(os.Args[1]), os.Getpid())
-       run("shell", "mkdir", "-p", deviceGotmp)
+       run("exec-out", "mkdir", "-p", deviceGotmp)
 
        // Determine the package by examining the current working
        // directory, which will look something like
@@ -94,7 +94,7 @@ func main() {
        } else {
                adbSyncGoroot()
        }
-       run("shell", "mkdir", "-p", deviceCwd)
+       run("exec-out", "mkdir", "-p", deviceCwd)
 
        // Binary names can conflict.
        // E.g. template.test from the {html,text}/template packages.
@@ -114,16 +114,13 @@ func main() {
                for range quit {
                        // We don't have the PID of the running process; use the
                        // binary name instead.
-                       run("shell", "killall -QUIT "+binName)
+                       run("exec-out", "killall -QUIT "+binName)
                }
        }()
-       // The adb shell command will return an exit code of 0 regardless
-       // of the command run. E.g.
-       //      $ adb shell false
-       //      $ echo $?
-       //      0
+       // In light of
        // https://code.google.com/p/android/issues/detail?id=3254
-       // So we append the exitcode to the output and parse it from there.
+       // dont trust the exitcode of adb. Instead, append the exitcode to
+       // the output and parse it from there.
        const exitstr = "exitcode="
        cmd := `export TMPDIR="` + deviceGotmp + `"` +
                `; export GOROOT="` + deviceGoroot + `"` +
@@ -131,11 +128,11 @@ func main() {
                `; cd "` + deviceCwd + `"` +
                "; '" + deviceBin + "' " + strings.Join(os.Args[2:], " ") +
                "; echo -n " + exitstr + "$?"
-       output := run("shell", cmd)
+       output := run("exec-out", cmd)
        signal.Reset(syscall.SIGQUIT)
        close(quit)
 
-       run("shell", "rm", "-rf", deviceGotmp) // Clean up.
+       run("exec-out", "rm", "-rf", deviceGotmp) // Clean up.
 
        exitIdx := strings.LastIndex(output, exitstr)
        if exitIdx == -1 {
@@ -211,8 +208,8 @@ func adbSyncGoroot() {
                return
        }
        devRoot := "/data/local/tmp/goroot"
-       run("shell", "rm", "-rf", devRoot)
-       run("shell", "mkdir", "-p", devRoot+"/pkg")
+       run("exec-out", "rm", "-rf", devRoot)
+       run("exec-out", "mkdir", "-p", devRoot+"/pkg")
        goroot := runtime.GOROOT()
        goCmd := filepath.Join(goroot, "bin", "go")
        runtimea, err := exec.Command(goCmd, "list", "-f", "{{.Target}}", "runtime").Output()