Fix dhcpcd-online for recent libdhcpcd changes
[dhcpcd-ui] / src / dhcpcd-online / dhcpcd-online.c
1 /*
2  * dhcpcd-online
3  * Copyright 2014-2015 Roy Marples <roy@marples.name>
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26
27 #include <errno.h>
28 #include <limits.h>
29 #include <poll.h>
30 #include <stdbool.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <syslog.h>
35 #include <time.h>
36 #include <unistd.h>
37
38 #include "dhcpcd.h"
39
40 #if __GNUC__ > 2 || defined(__INTEL_COMPILER)
41 # ifndef __dead
42 #  define __dead __attribute__((__noreturn__))
43 # endif
44 # ifndef __unused
45 #  define __unused   __attribute__((__unused__))
46 # endif
47 #else
48 # ifndef __dead
49 #  define __dead
50 # endif
51 # ifndef __unused
52 #  define __unused
53 # endif
54 #endif
55
56 #ifndef timespeccmp
57 #define timespeccmp(tsp, usp, cmp)                                      \
58         (((tsp)->tv_sec == (usp)->tv_sec) ?                             \
59             ((tsp)->tv_nsec cmp (usp)->tv_nsec) :                       \
60             ((tsp)->tv_sec cmp (usp)->tv_sec))
61 #endif
62 #ifndef timespecsub
63 #define timespecsub(tsp, usp, vsp)                                      \
64         do {                                                            \
65                 (vsp)->tv_sec = (tsp)->tv_sec - (usp)->tv_sec;          \
66                 (vsp)->tv_nsec = (tsp)->tv_nsec - (usp)->tv_nsec;       \
67                 if ((vsp)->tv_nsec < 0) {                               \
68                         (vsp)->tv_sec--;                                \
69                         (vsp)->tv_nsec += 1000000000L;                  \
70                 }                                                       \
71         } while (/* CONSTCOND */ 0)
72 #endif
73
74 static void __dead
75 do_exit(DHCPCD_CONNECTION *con, int code)
76 {
77
78         /* Unregister the status callback so that close doesn't spam. */
79         dhcpcd_set_status_callback(con, NULL, NULL);
80
81         dhcpcd_close(con);
82         dhcpcd_free(con);
83         exit(code);
84 }
85
86 static void
87 do_status_cb(DHCPCD_CONNECTION *con,
88     unsigned int status, const char *status_msg, void *arg)
89 {
90         struct pollfd *pfd;
91
92         syslog(LOG_INFO, "%s", status_msg);
93         switch (status)
94         {
95         case DHC_CONNECTED:
96                 do_exit(con, EXIT_SUCCESS);
97                 break;
98         case DHC_DOWN:
99                 pfd = arg;
100                 pfd->fd = -1;
101                 break;
102         }
103 }
104
105 int
106 main(int argc, char **argv)
107 {
108         DHCPCD_CONNECTION *con;
109         bool xflag;
110         struct timespec now, end, t;
111         struct pollfd pfd;
112         int timeout, n, lerrno;
113         long lnum;
114         char *lend;
115
116         /* Defaults */
117         timeout = 30;
118
119         xflag = false;
120
121         openlog("dhcpcd-online", LOG_PERROR, 0);
122         setlogmask(LOG_UPTO(LOG_INFO));
123
124         while ((n = getopt(argc, argv, "qt:x")) != -1) {
125                 switch (n) {
126                 case 'q':
127                         closelog();
128                         openlog("dhcpcd-online", 0, 0);
129                         break;
130                 case 't':
131                         lnum = strtol(optarg, &lend, 0);
132                         if (lend == NULL || *lend != '\0' ||
133                             lnum < 0 || lnum > INT_MAX)
134                         {
135                                 syslog(LOG_ERR, "-t %s: invalid timeout",
136                                     optarg);
137                                 exit(EXIT_FAILURE);
138                         }
139                         timeout = (int)lnum;
140                         break;
141                 case 'x':
142                         xflag = true;
143                         break;
144                 case '?':
145                         fprintf(stderr, "usage: dhcpcd-online "
146                             "[-q] [-t timeout]\n");
147                         exit(EXIT_FAILURE);
148                 }
149         }
150
151         if ((con = dhcpcd_new()) == NULL) {
152                 syslog(LOG_ERR, "dhcpcd_new: %m");
153                 return EXIT_FAILURE;
154         }
155
156         dhcpcd_set_status_callback(con, do_status_cb, &pfd);
157
158         if ((pfd.fd = dhcpcd_open(con, false)) == -1) {
159                 lerrno = errno;
160                 syslog(LOG_WARNING, "dhcpcd_open: %m");
161                 if (xflag)
162                         do_exit(con, EXIT_FAILURE);
163         } else
164                 lerrno = 0;
165         pfd.events = POLLIN;
166         pfd.revents = 0;
167
168         /* Work out our timeout time */
169         if (clock_gettime(CLOCK_MONOTONIC, &end) == -1) {
170                 syslog(LOG_ERR, "clock_gettime: %m");
171                 do_exit(con, EXIT_FAILURE);
172         }
173         end.tv_sec += timeout;
174
175         for (;;) {
176                 if (clock_gettime(CLOCK_MONOTONIC, &now) == -1) {
177                         syslog(LOG_ERR, "clock_gettime: %m");
178                         do_exit(con, EXIT_FAILURE);
179                 }
180                 if (timespeccmp(&now, &end, >)) {
181                         syslog(LOG_ERR, "timed out");
182                         do_exit(con, EXIT_FAILURE);
183                 }
184                 if (pfd.fd == -1) {
185                         n = poll(NULL, 0, DHCPCD_RETRYOPEN);
186                 } else {
187                         /* poll(2) should really take a timespec */
188                         timespecsub(&end, &now, &t);
189                         if (t.tv_sec > INT_MAX / 1000 ||
190                             (t.tv_sec == INT_MAX / 1000 &&
191                             (t.tv_nsec + 999999) / 1000000 > INT_MAX % 1000000))
192                                 timeout = INT_MAX;
193                         else
194                                 timeout = (int)(t.tv_sec * 1000 +
195                                     (t.tv_nsec + 999999) / 1000000);
196                         n = poll(&pfd, 1, timeout);
197                 }
198                 if (n == -1) {
199                         syslog(LOG_ERR, "poll: %m");
200                         do_exit(con, EXIT_FAILURE);
201                 }
202                 if (pfd.fd == -1) {
203                         if ((pfd.fd = dhcpcd_open(con, false)) == -1) {
204                                 if (lerrno != errno) {
205                                         lerrno = errno;
206                                         syslog(LOG_WARNING, "dhcpcd_open: %m");
207                                 }
208                         }
209                 } else {
210                         if (n > 0 && pfd.revents)
211                                 dhcpcd_dispatch(con);
212                 }
213         }
214
215         /* Impossible to reach here */
216         do_exit(con, EXIT_FAILURE);
217 }