Added udev operation mode and -x/-X options to kill a running instance.

1 files changed, 64 insertions, 13 deletions

diff --git a/usbmuxd/main.c b/usbmuxd/main.c
index 88c31da..579a21f 100644
--- a/usbmuxd/main.c
+++ b/usbmuxd/main.c
@@ -47,11 +47,12 @@ static const char *lockfile = "/var/run/usbmuxd.lock";
 
 int should_exit;
 
-struct sigaction sa_old;
-
 static int verbose = 0;
 static int foreground = 0;
 static int drop_privileges = 0;
+static int opt_udev = 0;
+static int opt_exit = 0;
+static int exit_signal = 0;
 
 int create_socket(void) {
         struct sockaddr_un bind_addr;
@@ -89,13 +90,19 @@ int create_socket(void) {
 
 void handle_signal(int sig)
 {
-        if(sig == SIGINT) {
-                usbmuxd_log(LL_NOTICE,"Caught SIGINT");
+        if (sig == SIGTERM) {
+                should_exit = 1;
         } else {
-                usbmuxd_log(LL_NOTICE,"Caught unknown signal %d", sig);
+                usbmuxd_log(LL_NOTICE,"Caught signal %d", sig);
+                usbmuxd_log(LL_INFO, "Checking if we can terminate (no more devices attached)...");
+                if (device_get_count() > 0) {
+                        // we can't quit, there are still devices attached.
+                        usbmuxd_log(LL_NOTICE, "Refusing to terminate, there are still devices attached. Kill me with signal 15 (TERM) to force quit.");
+                } else {
+                        // it's safe to quit
+                        should_exit = 1;
+                }
         }
-        should_exit = 1;
-        sigaction(SIGINT, &sa_old, NULL);
 }
 
 void set_signal_handlers(void)
@@ -103,7 +110,9 @@ void set_signal_handlers(void)
         struct sigaction sa;
         memset(&sa, 0, sizeof(struct sigaction));
         sa.sa_handler = handle_signal;
-        sigaction(SIGINT, &sa, &sa_old);
+        sigaction(SIGINT, &sa, NULL);
+        sigaction(SIGQUIT, &sa, NULL);
+        sigaction(SIGTERM, &sa, NULL);
 }
 
 int main_loop(int listenfd)
@@ -228,6 +237,10 @@ static void usage()
         printf("\t-v|--verbose              Be verbose (use twice or more to increase).\n");
         printf("\t-f|--foreground           Do not daemonize (implies a verbosity of 4).\n");
         printf("\t-d|--drop-privileges      Drop privileges after startup.\n");
+        printf("\t-u|--udev                 Run in udev operation mode.\n");
+        printf("\t-x|--exit                 Tell a running instance to exit.\n");
+        printf("\t-X|--force-exit           Tell a running instance to exit, even if\n");
+        printf("\t                          there are still devices connected.\n");
         printf("\n");
 }
 
@@ -238,12 +251,15 @@ static void parse_opts(int argc, char **argv)
                 {"foreground", 0, NULL, 'f'},
                 {"verbose", 0, NULL, 'v'},
                 {"drop-privileges", 0, NULL, 'd'},
+                {"udev", 0, NULL, 'u'},
+                {"exit", 0, NULL, 'x'},
+                {"force-exit", 0, NULL, 'X'},
                 {NULL, 0, NULL, 0}
         };
         int c;
 
         while (1) {
-                c = getopt_long(argc, argv, "hfvd", longopts, (int *) 0);
+                c = getopt_long(argc, argv, "hfvduxX", longopts, (int *) 0);
                 if (c == -1) {
                         break;
                 }
@@ -261,11 +277,24 @@ static void parse_opts(int argc, char **argv)
                 case 'd':
                         drop_privileges = 1;
                         break;
+                case 'u':
+                        opt_udev = 1;
+                        break;
+                case 'x':
+                        opt_exit = 1;
+                        exit_signal = SIGQUIT;
+                        break;
+                case 'X':
+                        opt_exit = 1;
+                        exit_signal = SIGTERM;
+                        break;
                 default:
                         usage();
                         exit(2);
                 }
         }
+        if (opt_udev)
+                foreground = 0;
 }
 
 int main(int argc, char *argv[])
@@ -303,13 +332,35 @@ int main(int argc, char *argv[])
                 fcntl(fileno(lfd), F_GETLK, &lock);
                 fclose(lfd);
                 if (lock.l_type != F_UNLCK) {
-                        usbmuxd_log(LL_NOTICE,
-                                   "another instance is already running (pid %d). exiting.", lock.l_pid);
-                        res = -1;
-                        goto terminate;
+                        if (opt_exit) {
+                                if (lock.l_pid && !kill(lock.l_pid, 0)) {
+                                        usbmuxd_log(LL_NOTICE, "sending signal %d to instance with pid %d", exit_signal, lock.l_pid);
+                                        if (kill(lock.l_pid, exit_signal) < 0) {
+                                                usbmuxd_log(LL_ERROR, "Error: could not deliver signal %d to pid %d", exit_signal, lock.l_pid);
+                                        }
+                                        res = 0;
+                                        goto terminate;
+                                } else {
+                                        usbmuxd_log(LL_ERROR, "Error: could not determine pid of the other running instance!");
+                                        res = -1;
+                                        goto terminate;
+                                }
+                        } else {
+                                usbmuxd_log(LL_NOTICE,
+                                           "another instance is already running (pid %d). exiting.", lock.l_pid);
+                                if (!opt_udev) {
+                                        res = -1;
+                                }
+                                goto terminate;
+                        }
                 }
         }
 
+        if (opt_exit) {
+                usbmuxd_log(LL_NOTICE, "no running instance found, none killed. exiting.");
+                goto terminate;
+        }
+
         usbmuxd_log(LL_INFO, "Creating socket");
         listenfd = create_socket();
         if(listenfd < 0)