chiark / gitweb /
udevd: improve error message in case exec() fails
[elogind.git] / udev / udevadm-settle.c
index 8a765f61cf6b83bc02a4c433c65a1f23ec2bb5fc..9492abd401e0dbb8f9efd193ac383d045139ac29 100644 (file)
@@ -1,5 +1,7 @@
 /*
- * Copyright (C) 2006-2008 Kay Sievers <kay@vrfy.org>
+ * Copyright (C) 2006-2009 Kay Sievers <kay@vrfy.org>
+ * Copyright (C) 2009 Canonical Ltd.
+ * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
 #include <fcntl.h>
 #include <syslog.h>
 #include <getopt.h>
+#include <signal.h>
+#include <time.h>
+#include <sys/inotify.h>
+#include <sys/poll.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 
 #include "udev.h"
 
-#define DEFAULT_TIMEOUT                        180
-#define LOOP_PER_SECOND                        20
-
 int udevadm_settle(struct udev *udev, int argc, char *argv[])
 {
        static const struct option options[] = {
+               { "seq-start", required_argument, NULL, 's' },
+               { "seq-end", required_argument, NULL, 'e' },
                { "timeout", required_argument, NULL, 't' },
+               { "exit-if-exists", required_argument, NULL, 'E' },
                { "quiet", no_argument, NULL, 'q' },
                { "help", no_argument, NULL, 'h' },
                {}
        };
-       int timeout = DEFAULT_TIMEOUT;
+       unsigned long long start_usec = now_usec();
+       unsigned long long start = 0;
+       unsigned long long end = 0;
        int quiet = 0;
+       const char *exists = NULL;
+       unsigned int timeout = 120;
+       struct pollfd pfd[1];
        struct udev_queue *udev_queue = NULL;
-       int loop;
-       int rc = 0;
+       int rc = EXIT_FAILURE;
 
        dbg(udev, "version %s\n", VERSION);
 
-       while (1) {
+       for (;;) {
                int option;
                int seconds;
 
-               option = getopt_long(argc, argv, "t:qh", options, NULL);
+               option = getopt_long(argc, argv, "s:e:t:E:qh", options, NULL);
                if (option == -1)
                        break;
 
                switch (option) {
+               case 's':
+                       start = strtoull(optarg, NULL, 0);
+                       break;
+               case 'e':
+                       end = strtoull(optarg, NULL, 0);
+                       break;
                case 't':
                        seconds = atoi(optarg);
                        if (seconds >= 0)
@@ -69,35 +85,137 @@ int udevadm_settle(struct udev *udev, int argc, char *argv[])
                case 'q':
                        quiet = 1;
                        break;
+               case 'E':
+                       exists = optarg;
+                       break;
                case 'h':
-                       printf("Usage: udevadm settle [--help] [--timeout=<seconds>] [--quiet]\n\n");
-                       goto exit;
+                       printf("Usage: udevadm settle OPTIONS\n"
+                              "  --timeout=<seconds>     maximum time to wait for events\n"
+                              "  --seq-start=<seqnum>    first seqnum to wait for\n"
+                              "  --seq-end=<seqnum>      last seqnum to wait for\n"
+                              "  --exit-if-exists=<file> stop waiting if file exists\n"
+                              "  --quiet                 do not print list after timeout\n"
+                              "  --help\n\n");
+                       exit(0);
                }
        }
 
        udev_queue = udev_queue_new(udev);
        if (udev_queue == NULL)
-               goto exit;
-       loop = timeout * LOOP_PER_SECOND;
-       while (loop--) {
-               if (udev_queue_get_queue_is_empty(udev_queue))
-                       break;
-               usleep(1000 * 1000 / LOOP_PER_SECOND);
+               exit(2);
+
+       if (start > 0) {
+               unsigned long long kernel_seq;
+
+               kernel_seq = udev_queue_get_kernel_seqnum(udev_queue);
+
+               /* unless specified, the last event is the current kernel seqnum */
+               if (end == 0)
+                       end = udev_queue_get_kernel_seqnum(udev_queue);
+
+               if (start > end) {
+                       err(udev, "seq-start larger than seq-end, ignoring\n");
+                       start = 0;
+                       end = 0;
+               }
+
+               if (start > kernel_seq || end > kernel_seq) {
+                       err(udev, "seq-start or seq-end larger than current kernel value, ignoring\n");
+                       start = 0;
+                       end = 0;
+               }
+               info(udev, "start=%llu end=%llu current=%llu\n", start, end, kernel_seq);
+       } else {
+               if (end > 0) {
+                       err(udev, "seq-end needs seq-start parameter, ignoring\n");
+                       end = 0;
+               }
+       }
+
+       /* guarantee that the udev daemon isn't pre-processing */
+       if (getuid() == 0) {
+               struct udev_ctrl *uctrl;
+
+               uctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
+               if (uctrl != NULL) {
+                       if (udev_ctrl_send_ping(uctrl, timeout) < 0) {
+                               info(udev, "no connection to daemon\n");
+                               udev_ctrl_unref(uctrl);
+                               rc = EXIT_SUCCESS;
+                               goto out;
+                       }
+                       udev_ctrl_unref(uctrl);
+               }
        }
-       if (loop <= 0) {
-               struct udev_list_entry *list_entry;
-
-               if (!quiet) {
-                       info(udev, "timeout waiting for udev queue\n");
-                       printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
-                       udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
-                               printf("  %s (%s)\n",
-                                      udev_list_entry_get_name(list_entry),
-                                      udev_list_entry_get_value(list_entry));
+
+       pfd[0].events = POLLIN;
+       pfd[0].fd = inotify_init1(IN_CLOEXEC);
+       if (pfd[0].fd < 0) {
+               err(udev, "inotify_init failed: %m\n");
+       } else {
+               if (inotify_add_watch(pfd[0].fd, udev_get_run_path(udev), IN_CLOSE_WRITE) < 0) {
+                       err(udev, "watching '%s' failed\n", udev_get_run_path(udev));
+                       close(pfd[0].fd);
+                       pfd[0].fd = -1;
+               }
+       }
+
+       for (;;) {
+               struct stat statbuf;
+
+               if (exists != NULL && stat(exists, &statbuf) == 0) {
+                       rc = EXIT_SUCCESS;
+                       break;
+               }
+
+               if (start > 0) {
+                       /* if asked for, wait for a specific sequence of events */
+                       if (udev_queue_get_seqnum_sequence_is_finished(udev_queue, start, end) == 1) {
+                               rc = EXIT_SUCCESS;
+                               break;
+                       }
+               } else {
+                       /* exit if queue is empty */
+                       if (udev_queue_get_queue_is_empty(udev_queue)) {
+                               rc = EXIT_SUCCESS;
+                               break;
+                       }
+               }
+
+               if (pfd[0].fd >= 0) {
+                       /* wake up once every second, or whenever the queue file gets gets closed */
+                       if (poll(pfd, 1, 1000) > 0 && pfd[0].revents & POLLIN) {
+                               char buf[sizeof(struct inotify_event) + PATH_MAX];
+
+                               read(pfd[0].fd, buf, sizeof(buf));
+                       }
+               } else {
+                       sleep(1);
+               }
+
+               if (timeout > 0) {
+                       unsigned long long age_usec;
+
+                       age_usec = now_usec() - start_usec;
+                       if (age_usec / (1000 * 1000) >= timeout) {
+                               struct udev_list_entry *list_entry;
+
+                               if (!quiet && udev_queue_get_queued_list_entry(udev_queue) != NULL) {
+                                       info(udev, "timeout waiting for udev queue\n");
+                                       printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
+                                       udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
+                                               printf("  %s (%s)\n",
+                                               udev_list_entry_get_name(list_entry),
+                                               udev_list_entry_get_value(list_entry));
+                               }
+
+                               break;
+                       }
                }
-               rc = 1;
        }
-exit:
+out:
+       if (pfd[0].fd >= 0)
+               close(pfd[0].fd);
        udev_queue_unref(udev_queue);
        return rc;
 }