sysdeps-unix: Diagnose failure to open /proc/self/oom_score_adj

Previously, we silently ignored this, but now that we're more careful
about the contexts in which we try to reset the OOM score and whether
we log failures as a warning, we can let the dbus-daemon-launch-helper
show a message if it can't write there.

Signed-off-by: Simon McVittie <smcv@collabora.com>
(cherry picked from commit 226f24144a4db4898a1f5958293d200b975baee0)

diff --git a/dbus/dbus-sysdeps-util-unix.c b/dbus/dbus-sysdeps-util-unix.c
index ffbc7ae..bed6fd3 100644 (file)
--- a/dbus/dbus-sysdeps-util-unix.c
+++ b/dbus/dbus-sysdeps-util-unix.c
@@ -1658,12 +1658,19 @@ _dbus_reset_oom_score_adj (const char **error_str_p)
       /* Success */
       ret = TRUE;
     }
-  else
+  else if (errno == ENOENT)
     {
-      /* TODO: Historically we ignored this error, although ideally we
-       * would diagnose it */
+      /* If /proc/self/oom_score_adj doesn't exist, assume the kernel
+       * doesn't support this feature and ignore it. */
       ret = TRUE;
     }
+  else
+    {
+      ret = FALSE;
+      error_str = "open(/proc/self/oom_score_adj)";
+      saved_errno = errno;
+      goto out;
+    }
 
 out:
   if (fd >= 0)