interface-event.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <unistd.h>
   5
   6 #include <libubox/uloop.h>
   7
   8 #include "netifd.h"
   9 #include "interface.h"
  10 #include "ubus.h"
  11
  12 char *hotplug_cmd_path = DEFAULT_HOTPLUG_PATH;
  13 static struct interface *current;
  14 static enum interface_event current_ev;
  15 static struct list_head pending = LIST_HEAD_INIT(pending);
  16
  17 static void task_complete(struct uloop_process *proc, int ret);
  18 static struct uloop_process task = {
  19         .cb = task_complete,
  20 };
  21
  22 static void
  23 run_cmd(const char *ifname, bool up)
  24 {
  25         char *argv[3];
  26         int pid;
  27
  28         pid = fork();
  29         if (pid < 0)
  30                 return task_complete(NULL, -1);
  31
  32         if (pid > 0) {
  33                 task.pid = pid;
  34                 uloop_process_add(&task);
  35                 return;
  36         }
  37
  38         setenv("ACTION", up ? "ifup" : "ifdown", 1);
  39         setenv("INTERFACE", ifname, 1);
  40         argv[0] = hotplug_cmd_path;
  41         argv[1] = "network";
  42         argv[2] = NULL;
  43         execvp(argv[0], argv);
  44         exit(127);
  45 }
  46
  47 static void
  48 call_hotplug(void)
  49 {
  50         if (list_empty(&pending))
  51                 return;
  52
  53         current = list_first_entry(&pending, struct interface, hotplug_list);
  54         current_ev = current->hotplug_ev;
  55         list_del_init(&current->hotplug_list);
  56
  57         D(SYSTEM, "Call hotplug handler for interface '%s'\n", current->name);
  58         run_cmd(current->name, current_ev == IFEV_UP);
  59 }
  60
  61 static void
  62 task_complete(struct uloop_process *proc, int ret)
  63 {
  64         if (current)
  65                 D(SYSTEM, "Complete hotplug handler for interface '%s'\n", current->name);
  66         current = NULL;
  67         call_hotplug();
  68 }
  69
  70 /*
  71  * Queue an interface for an up/down event.
  72  * An interface can only have one event in the queue and one
  73  * event waiting for completion.
  74  * When queueing an event that is the same as the one waiting for
  75  * completion, remove the interface from the queue
  76  */
  77 void
  78 interface_queue_event(struct interface *iface, enum interface_event ev)
  79 {
  80         enum interface_event last_ev;
  81
  82         D(SYSTEM, "Queue hotplug handler for interface '%s'\n", iface->name);
  83         netifd_ubus_interface_event(iface, ev == IFEV_UP);
  84         if (current == iface)
  85                 last_ev = current_ev;
  86         else
  87                 last_ev = iface->hotplug_ev;
  88
  89         iface->hotplug_ev = ev;
  90         if (last_ev == ev && !list_empty(&iface->hotplug_list))
  91                 list_del(&iface->hotplug_list);
  92         else if (last_ev != ev && list_empty(&iface->hotplug_list))
  93                 list_add(&iface->hotplug_list, &pending);
  94
  95         if (!task.pending && !current)
  96                 call_hotplug();
  97 }
  98
  99 void
 100 interface_dequeue_event(struct interface *iface)
 101 {
 102         if (iface == current)
 103                 current = NULL;
 104
 105         if (!list_empty(&iface->hotplug_list))
 106                 list_del_init(&iface->hotplug_list);
 107 }