chiark / gitweb /
udevd: clarify worker exit status
[elogind.git] / udev / udevadm-monitor.c
1 /*
2  * Copyright (C) 2004-2010 Kay Sievers <kay.sievers@vrfy.org>
3  *
4  * This program is free software: you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation, either version 2 of the License, or
7  * (at your option) any later version.
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  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17
18 #include <unistd.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <stddef.h>
22 #include <string.h>
23 #include <fcntl.h>
24 #include <errno.h>
25 #include <signal.h>
26 #include <getopt.h>
27 #include <sys/time.h>
28 #include <sys/socket.h>
29 #include <sys/un.h>
30 #include <sys/epoll.h>
31 #include <linux/types.h>
32 #include <linux/netlink.h>
33
34 #include "udev.h"
35
36 static bool udev_exit;
37
38 static void sig_handler(int signum)
39 {
40         if (signum == SIGINT || signum == SIGTERM)
41                 udev_exit = true;
42 }
43
44 static void print_device(struct udev_device *device, const char *source, int prop)
45 {
46         struct timeval tv;
47         struct timezone tz;
48
49         gettimeofday(&tv, &tz);
50         printf("%-6s[%llu.%06u] %-8s %s (%s)\n",
51                source,
52                (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec,
53                udev_device_get_action(device),
54                udev_device_get_devpath(device),
55                udev_device_get_subsystem(device));
56         if (prop) {
57                 struct udev_list_entry *list_entry;
58
59                 udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(device))
60                         printf("%s=%s\n",
61                                udev_list_entry_get_name(list_entry),
62                                udev_list_entry_get_value(list_entry));
63                 printf("\n");
64         }
65 }
66
67 int udevadm_monitor(struct udev *udev, int argc, char *argv[])
68 {
69         struct sigaction act;
70         sigset_t mask;
71         int option;
72         bool prop = false;
73         bool print_kernel = false;
74         bool print_udev = false;
75         struct udev_list_node subsystem_match_list;
76         struct udev_list_node tag_match_list;
77         struct udev_monitor *udev_monitor = NULL;
78         struct udev_monitor *kernel_monitor = NULL;
79         int fd_ep = -1;
80         int fd_kernel = -1, fd_udev = -1;
81         struct epoll_event ep_kernel, ep_udev;
82         int rc = 0;
83
84         static const struct option options[] = {
85                 { "property", no_argument, NULL, 'p' },
86                 { "environment", no_argument, NULL, 'e' },
87                 { "kernel", no_argument, NULL, 'k' },
88                 { "udev", no_argument, NULL, 'u' },
89                 { "subsystem-match", required_argument, NULL, 's' },
90                 { "tag-match", required_argument, NULL, 't' },
91                 { "help", no_argument, NULL, 'h' },
92                 {}
93         };
94
95         udev_list_init(&subsystem_match_list);
96         udev_list_init(&tag_match_list);
97
98         for (;;) {
99                 option = getopt_long(argc, argv, "pekus:t:h", options, NULL);
100                 if (option == -1)
101                         break;
102
103                 switch (option) {
104                 case 'p':
105                 case 'e':
106                         prop = true;
107                         break;
108                 case 'k':
109                         print_kernel = true;
110                         break;
111                 case 'u':
112                         print_udev = true;
113                         break;
114                 case 's':
115                         {
116                                 char subsys[UTIL_NAME_SIZE];
117                                 char *devtype;
118
119                                 util_strscpy(subsys, sizeof(subsys), optarg);
120                                 devtype = strchr(subsys, '/');
121                                 if (devtype != NULL) {
122                                         devtype[0] = '\0';
123                                         devtype++;
124                                 }
125                                 udev_list_entry_add(udev, &subsystem_match_list, subsys, devtype, 0, 0);
126                                 break;
127                         }
128                 case 't':
129                         udev_list_entry_add(udev, &tag_match_list, optarg, NULL, 0, 0);
130                         break;
131                 case 'h':
132                         printf("Usage: udevadm monitor [--property] [--kernel] [--udev] [--help]\n"
133                                "  --property                              print the event properties\n"
134                                "  --kernel                                print kernel uevents\n"
135                                "  --udev                                  print udev events\n"
136                                "  --subsystem-match=<subsystem[/devtype]> filter events by subsystem\n"
137                                "  --tag-match=<tag>                       filter events by tag\n"
138                                "  --help\n\n");
139                         goto out;
140                 }
141         }
142
143         if (!print_kernel && !print_udev) {
144                 print_kernel = true;
145                 print_udev = true;
146         }
147
148         /* set signal handlers */
149         memset(&act, 0x00, sizeof(struct sigaction));
150         act.sa_handler = sig_handler;
151         sigemptyset(&act.sa_mask);
152         act.sa_flags = SA_RESTART;
153         sigaction(SIGINT, &act, NULL);
154         sigaction(SIGTERM, &act, NULL);
155         sigemptyset(&mask);
156         sigaddset(&mask, SIGINT);
157         sigaddset(&mask, SIGTERM);
158         sigprocmask(SIG_UNBLOCK, &mask, NULL);
159
160         fd_ep = epoll_create1(EPOLL_CLOEXEC);
161         if (fd_ep < 0) {
162                 err(udev, "error creating epoll fd: %m\n");
163                 goto out;
164         }
165
166         printf("monitor will print the received events for:\n");
167         if (print_udev) {
168                 struct udev_list_entry *entry;
169
170                 udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
171                 if (udev_monitor == NULL) {
172                         fprintf(stderr, "error: unable to create netlink socket\n");
173                         rc = 1;
174                         goto out;
175                 }
176                 udev_monitor_set_receive_buffer_size(udev_monitor, 128*1024*1024);
177                 fd_udev = udev_monitor_get_fd(udev_monitor);
178
179                 udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
180                         const char *subsys = udev_list_entry_get_name(entry);
181                         const char *devtype = udev_list_entry_get_value(entry);
182
183                         if (udev_monitor_filter_add_match_subsystem_devtype(udev_monitor, subsys, devtype) < 0)
184                                 fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
185                 }
186
187                 udev_list_entry_foreach(entry, udev_list_get_entry(&tag_match_list)) {
188                         const char *tag = udev_list_entry_get_name(entry);
189
190                         if (udev_monitor_filter_add_match_tag(udev_monitor, tag) < 0)
191                                 fprintf(stderr, "error: unable to apply tag filter '%s'\n", tag);
192                 }
193
194                 if (udev_monitor_enable_receiving(udev_monitor) < 0) {
195                         fprintf(stderr, "error: unable to subscribe to udev events\n");
196                         rc = 2;
197                         goto out;
198                 }
199
200                 memset(&ep_udev, 0, sizeof(struct epoll_event));
201                 ep_udev.events = EPOLLIN;
202                 ep_udev.data.fd = fd_udev;
203                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_udev, &ep_udev) < 0) {
204                         err(udev, "fail to add fd to epoll: %m\n");
205                         goto out;
206                 }
207
208                 printf("UDEV - the event which udev sends out after rule processing\n");
209         }
210
211         if (print_kernel) {
212                 struct udev_list_entry *entry;
213
214                 kernel_monitor = udev_monitor_new_from_netlink(udev, "kernel");
215                 if (kernel_monitor == NULL) {
216                         fprintf(stderr, "error: unable to create netlink socket\n");
217                         rc = 3;
218                         goto out;
219                 }
220                 udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024);
221                 fd_kernel = udev_monitor_get_fd(kernel_monitor);
222
223                 udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
224                         const char *subsys = udev_list_entry_get_name(entry);
225
226                         if (udev_monitor_filter_add_match_subsystem_devtype(kernel_monitor, subsys, NULL) < 0)
227                                 fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
228                 }
229
230                 if (udev_monitor_enable_receiving(kernel_monitor) < 0) {
231                         fprintf(stderr, "error: unable to subscribe to kernel events\n");
232                         rc = 4;
233                         goto out;
234                 }
235
236                 memset(&ep_kernel, 0, sizeof(struct epoll_event));
237                 ep_kernel.events = EPOLLIN;
238                 ep_kernel.data.fd = fd_kernel;
239                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_kernel, &ep_kernel) < 0) {
240                         err(udev, "fail to add fd to epoll: %m\n");
241                         goto out;
242                 }
243
244                 printf("KERNEL - the kernel uevent\n");
245         }
246         printf("\n");
247
248         while (!udev_exit) {
249                 int fdcount;
250                 struct epoll_event ev[4];
251                 int i;
252
253                 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
254                 if (fdcount < 0) {
255                         if (errno != EINTR)
256                                 fprintf(stderr, "error receiving uevent message: %m\n");
257                         continue;
258                 }
259
260                 for (i = 0; i < fdcount; i++) {
261                         if (ev[i].data.fd == fd_kernel && ev[i].events & EPOLLIN) {
262                                 struct udev_device *device;
263
264                                 device = udev_monitor_receive_device(kernel_monitor);
265                                 if (device == NULL)
266                                         continue;
267                                 print_device(device, "KERNEL", prop);
268                                 udev_device_unref(device);
269                         } else if (ev[i].data.fd == fd_udev && ev[i].events & EPOLLIN) {
270                                 struct udev_device *device;
271
272                                 device = udev_monitor_receive_device(udev_monitor);
273                                 if (device == NULL)
274                                         continue;
275                                 print_device(device, "UDEV", prop);
276                                 udev_device_unref(device);
277                         }
278                 }
279         }
280 out:
281         if (fd_ep >= 0)
282                 close(fd_ep);
283         udev_monitor_unref(udev_monitor);
284         udev_monitor_unref(kernel_monitor);
285         udev_list_cleanup_entries(udev, &subsystem_match_list);
286         udev_list_cleanup_entries(udev, &tag_match_list);
287         return rc;
288 }