ubus.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <sys/resource.h>
  16 #include <stdlib.h>
  17 #include <unistd.h>
  18 #include <signal.h>
  19
  20 #include "procd.h"
  21
  22 char *ubus_socket = NULL;
  23 static struct ubus_context *ctx;
  24 static struct uloop_process ubus_proc;
  25 static bool ubus_connected = false;
  26
  27 static void procd_ubus_connection_lost(struct ubus_context *old_ctx);
  28
  29 static void ubus_proc_cb(struct uloop_process *proc, int ret)
  30 {
  31         /* nothing to do here */
  32 }
  33
  34 static void procd_restart_ubus(void)
  35 {
  36         char *argv[] = { "ubusd", NULL, ubus_socket, NULL };
  37
  38         if (ubus_proc.pending) {
  39                 ERROR("Killing existing ubus instance, pid=%d\n", (int) ubus_proc.pid);
  40                 kill(ubus_proc.pid, SIGKILL);
  41                 uloop_process_delete(&ubus_proc);
  42         }
  43
  44         if (ubus_socket)
  45                 argv[1] = "-s";
  46
  47         ubus_proc.pid = fork();
  48         if (!ubus_proc.pid) {
  49                 setpriority(PRIO_PROCESS, 0, -20);
  50                 execvp(argv[0], argv);
  51                 exit(-1);
  52         }
  53
  54         if (ubus_proc.pid <= 0) {
  55                 ERROR("Failed to start new ubus instance\n");
  56                 return;
  57         }
  58
  59         DEBUG(1, "Launched new ubus instance, pid=%d\n", (int) ubus_proc.pid);
  60         uloop_process_add(&ubus_proc);
  61 }
  62
  63 static void procd_ubus_try_connect(void)
  64 {
  65         if (ctx) {
  66                 ubus_connected = !ubus_reconnect(ctx, ubus_socket);
  67                 return;
  68         }
  69
  70         ctx = ubus_connect(ubus_socket);
  71         if (!ctx) {
  72                 DEBUG(2, "Connection to ubus failed\n");
  73                 return;
  74         }
  75
  76         ctx->connection_lost = procd_ubus_connection_lost;
  77         ubus_connected = true;
  78         ubus_init_service(ctx);
  79         if (getpid() == 1) {
  80                 ubus_init_log(ctx);
  81                 ubus_init_system(ctx);
  82         }
  83 }
  84
  85 static void procd_ubus_connection_lost(struct ubus_context *old_ctx)
  86 {
  87         procd_ubus_try_connect();
  88         while (!ubus_connected) {
  89                 procd_restart_ubus();
  90                 sleep(1);
  91                 procd_ubus_try_connect();
  92         }
  93
  94         DEBUG(1, "Connected to ubus, id=%08x\n", ctx->local_id);
  95         ubus_add_uloop(ctx);
  96 }
  97
  98 void procd_connect_ubus(void)
  99 {
 100         ubus_proc.cb = ubus_proc_cb;
 101         procd_ubus_connection_lost(NULL);
 102 }
 103