Merge lp:~robert-ancell/lightdm/process-cleanup into lp:lightdm

[Robert Ancell]

Make sure processes can only be stopped once, don't warn if process doesn't exist when sending it a signal (we will pick that up in the wait())

[Robert Ancell (robert-ancell)]

review: Approve

[PS Jenkins bot (ps-jenkins)]

review: Approve (continuous-integration)

=== modified file 'src/process.c'
--- src/process.c	2014-03-04 03:23:30 +0000
+++ src/process.c	2014-03-05 22:35:48 +0000
@@ -55,6 +55,9 @@
     /* Exit status of process */
     int exit_status;
 
+    /* TRUE if stopping this process (waiting for child process to stop) */
+    gboolean stopping;
+
     /* Timeout waiting for process to quit */
     guint quit_timeout;
 
@@ -292,7 +295,11 @@
     g_debug ("Sending signal %d to process %d", signum, process->priv->pid);
 
     if (kill (process->priv->pid, signum) < 0)
-        g_warning ("Error sending signal %d to process %d: %s", signum, process->priv->pid, strerror (errno));
+    {
+        /* Ignore ESRCH, we will pick that up in our wait */
+        if (errno != ESRCH)
+            g_warning ("Error sending signal %d to process %d: %s", signum, process->priv->pid, strerror (errno));
+    }
 }
 
 static gboolean
@@ -308,6 +315,14 @@
 {
     g_return_if_fail (process != NULL);
 
+    if (process->priv->stopping)
+        return;
+    process->priv->stopping = TRUE;
+
+    /* If already stopped then we're done! */
+    if (process->priv->pid == 0)
+        return;
+
     /* Send SIGTERM, and then SIGKILL if no response */
     process->priv->quit_timeout = g_timeout_add (5000, (GSourceFunc) quit_timeout_cb, process);
     process_signal (process, SIGTERM);