From: Tom Clegg <tclegg@veritasgenetics.com>
Date: Wed, 13 Feb 2019 16:11:03 +0000 (-0500)
Subject: 14807: Fix crunch-run --list output when /var/lock is a symlink.
X-Git-Tag: 1.4.0~142^2~20
X-Git-Url: https://git.arvados.org/arvados.git/commitdiff_plain/de9a5e2703cca69b0ba6e8e3e6102ee267b7447e

14807: Fix crunch-run --list output when /var/lock is a symlink.

filepath.Walk(/var/lock) does not return entries inside /var/lock if
/var/lock is a symlink, as it is on debian:9.

Arvados-DCO-1.1-Signed-off-by: Tom Clegg <tclegg@veritasgenetics.com>
---

diff --git a/services/crunch-run/background.go b/services/crunch-run/background.go
index a508538370..0d4612908c 100644
--- a/services/crunch-run/background.go
+++ b/services/crunch-run/background.go
@@ -155,8 +155,11 @@ func kill(uuid string, signal syscall.Signal, stdout, stderr io.Writer) error {
 
 // List UUIDs of active crunch-run processes.
 func ListProcesses(stdout, stderr io.Writer) int {
-	return exitcode(stderr, filepath.Walk(lockdir, func(path string, info os.FileInfo, err error) error {
-		if info.IsDir() {
+	// filepath.Walk does not follow symlinks, so we must walk
+	// lockdir+"/." in case lockdir itself is a symlink.
+	walkdir := lockdir + "/."
+	return exitcode(stderr, filepath.Walk(walkdir, func(path string, info os.FileInfo, err error) error {
+		if info.IsDir() && path != walkdir {
 			return filepath.SkipDir
 		}
 		if name := info.Name(); !strings.HasPrefix(name, lockprefix) || !strings.HasSuffix(name, locksuffix) {