Fix dhclient probe/remove race condition

diff --git a/plugins/dhclient.c b/plugins/dhclient.c
index 90f8e2f..56e1575 100644 (file)
--- a/plugins/dhclient.c
+++ b/plugins/dhclient.c
@@ -45,6 +45,7 @@ struct dhclient_task {
        int ifindex;
        gchar *ifname;
        struct connman_element *element;
+       struct dhclient_task *pending;
 };
 
 static GSList *task_list = NULL;
@@ -107,6 +108,8 @@ static void unlink_task(struct dhclient_task *task)
        g_free(pathname);
 }
 
+static int start_dhclient(struct dhclient_task *task);
+
 static void task_died(GPid pid, gint status, gpointer data)
 {
        struct dhclient_task *task = data;
@@ -123,6 +126,9 @@ static void task_died(GPid pid, gint status, gpointer data)
 
        unlink_task(task);
 
+       if (task->pending != NULL)
+               start_dhclient(task->pending);
+
        g_free(task->ifname);
        g_free(task);
 }
@@ -136,32 +142,11 @@ static void task_setup(gpointer data)
        task->killed = FALSE;
 }
 
-static int dhclient_probe(struct connman_element *element)
+static int start_dhclient(struct dhclient_task *task)
 {
-       struct dhclient_task *task;
        char *argv[16], *envp[1], address[128], pidfile[PATH_MAX];
        char leases[PATH_MAX], config[PATH_MAX], script[PATH_MAX];
 
-       DBG("element %p name %s", element, element->name);
-
-       if (access(DHCLIENT, X_OK) < 0)
-               return -errno;
-
-       task = g_try_new0(struct dhclient_task, 1);
-       if (task == NULL)
-               return -ENOMEM;
-
-       task->ifindex = element->index;
-       task->ifname = connman_inet_ifname(element->index);
-       task->element = element;
-
-       if (task->ifname == NULL) {
-               g_free(task);
-               return -ENOMEM;
-       }
-
-       DBG("request %s", task->ifname);
-
        snprintf(address, sizeof(address) - 1, "BUSNAME=%s", busname);
        snprintf(pidfile, sizeof(pidfile) - 1,
                        "%s/dhclient.%s.pid", STATEDIR, task->ifname);
@@ -204,6 +189,37 @@ static int dhclient_probe(struct connman_element *element)
        return 0;
 }
 
+static int dhclient_probe(struct connman_element *element)
+{
+       struct dhclient_task *task, *previous;
+       DBG("element %p name %s", element, element->name);
+
+       if (access(DHCLIENT, X_OK) < 0)
+               return -errno;
+
+       task = g_try_new0(struct dhclient_task, 1);
+       if (task == NULL)
+               return -ENOMEM;
+
+       task->ifindex = element->index;
+       task->ifname  = connman_inet_ifname(element->index);
+       task->element = element;
+
+       if (task->ifname == NULL) {
+               g_free(task);
+               return -ENOMEM;
+       }
+
+       previous= find_task_by_index(element->index);
+       if (previous != NULL) {
+               previous->pending = task;
+               kill_task(previous);
+               return 0;
+       }
+
+       return start_dhclient(task);
+}
+
 static void dhclient_remove(struct connman_element *element)
 {
        struct dhclient_task *task;