fix infinite loop in logging when the logged process dies
[project/netifd.git] / main.c
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <getopt.h>
5 #include <unistd.h>
6 #include <signal.h>
7 #include <stdarg.h>
8 #include <syslog.h>
9
10 #include "netifd.h"
11 #include "ubus.h"
12 #include "config.h"
13 #include "system.h"
14 #include "interface.h"
15
16 unsigned int debug_mask = 0;
17 const char *main_path = DEFAULT_MAIN_PATH;
18 const char *resolv_conf = DEFAULT_RESOLV_CONF;
19 static char **global_argv;
20
21 static struct list_head process_list = LIST_HEAD_INIT(process_list);
22 static struct list_head fds = LIST_HEAD_INIT(fds);
23
24 #define DEFAULT_LOG_LEVEL L_NOTICE
25
26 enum {
27 L_CRIT,
28 L_WARNING,
29 L_NOTICE,
30 L_INFO,
31 L_DEBUG
32 };
33
34 static int log_level = DEFAULT_LOG_LEVEL;
35 static const int log_class[] = {
36 [L_CRIT] = LOG_CRIT,
37 [L_WARNING] = LOG_WARNING,
38 [L_NOTICE] = LOG_NOTICE,
39 [L_INFO] = LOG_INFO,
40 [L_DEBUG] = LOG_DEBUG
41 };
42
43 #ifdef DUMMY_MODE
44 #define use_syslog false
45 #else
46 static bool use_syslog = true;
47 #endif
48
49
50 static void
51 netifd_delete_process(struct netifd_process *proc)
52 {
53 if (proc->uloop.pending)
54 uloop_process_delete(&proc->uloop);
55 list_del(&proc->list);
56 netifd_fd_delete(&proc->log_fd);
57 }
58
59 void
60 netifd_log_message(int priority, const char *format, ...)
61 {
62 va_list vl;
63
64 if (priority > log_level)
65 return;
66
67 va_start(vl, format);
68 if (use_syslog)
69 vsyslog(log_class[priority], format, vl);
70 else
71 vfprintf(stderr, format, vl);
72 va_end(vl);
73 }
74
75 static void
76 netifd_process_log_cb(struct uloop_fd *fd, unsigned int events)
77 {
78 struct netifd_process *proc;
79 const char *log_prefix;
80 char *buf, *cur;
81 int maxlen, len, read_len;
82
83 proc = container_of(fd, struct netifd_process, log_uloop);
84
85 if (!proc->log_buf)
86 proc->log_buf = malloc(LOG_BUF_SIZE + 1);
87
88 buf = proc->log_buf + proc->log_buf_ofs;
89 maxlen = LOG_BUF_SIZE - proc->log_buf_ofs;
90
91 log_prefix = proc->log_prefix;
92 if (!log_prefix)
93 log_prefix = "process";
94
95 retry:
96 read_len = len = read(fd->fd, buf, maxlen);
97 if (len <= 0) {
98 if (errno == EINTR)
99 goto retry;
100
101 goto out;
102 }
103 proc->log_buf_ofs += len;
104
105 cur = buf;
106 buf = proc->log_buf;
107 while ((cur = memchr(cur, '\n', len))) {
108 *cur = 0;
109
110 if (!proc->log_overflow)
111 netifd_log_message(L_NOTICE, "%s (%d): %s\n",
112 log_prefix, proc->uloop.pid, buf);
113 else
114 proc->log_overflow = false;
115
116 cur++;
117 len -= cur - buf;
118 buf = cur;
119 }
120
121 if (buf > proc->log_buf && len > 0)
122 memmove(buf, proc->log_buf, len);
123
124 if (len == LOG_BUF_SIZE) {
125 if (!proc->log_overflow) {
126 proc->log_buf[LOG_BUF_SIZE] = 0;
127 netifd_log_message(L_NOTICE, "%s (%d): %s [...]\n",
128 log_prefix, proc->uloop.pid, proc->log_buf);
129 proc->log_overflow = true;
130 }
131 len = 0;
132 }
133 proc->log_buf_ofs = len;
134
135 if (read_len == maxlen)
136 goto retry;
137
138 out:
139 if (fd->eof)
140 uloop_fd_delete(fd);
141 }
142
143 static void
144 netifd_process_cb(struct uloop_process *proc, int ret)
145 {
146 struct netifd_process *np;
147 np = container_of(proc, struct netifd_process, uloop);
148 netifd_process_log_cb(&np->log_uloop, 0);
149 netifd_delete_process(np);
150 return np->cb(np, ret);
151 }
152
153 int
154 netifd_start_process(const char **argv, char **env, struct netifd_process *proc)
155 {
156 struct netifd_fd *fd;
157 int pfds[2];
158 int pid;
159
160 netifd_kill_process(proc);
161
162 if (pipe(pfds) < 0)
163 return -1;
164
165 if ((pid = fork()) < 0)
166 goto error;
167
168 if (!pid) {
169 if (env) {
170 while (*env) {
171 putenv(*env);
172 env++;
173 }
174 }
175 if (proc->dir_fd >= 0)
176 fchdir(proc->dir_fd);
177
178 /* close all non-essential fds */
179 list_for_each_entry(fd, &fds, list) {
180 if (fd->proc == proc)
181 continue;
182 close(fd->fd);
183 }
184
185 dup2(pfds[1], 0);
186 dup2(pfds[1], 1);
187 dup2(pfds[1], 2);
188
189 close(pfds[0]);
190 close(pfds[1]);
191
192 execvp(argv[0], (char **) argv);
193 exit(127);
194 }
195
196 if (pid < 0)
197 goto error;
198
199 close(pfds[1]);
200 proc->uloop.cb = netifd_process_cb;
201 proc->uloop.pid = pid;
202 uloop_process_add(&proc->uloop);
203 list_add_tail(&proc->list, &process_list);
204
205 proc->log_uloop.fd = proc->log_fd.fd = pfds[0];
206 proc->log_uloop.cb = netifd_process_log_cb;
207 netifd_fd_add(&proc->log_fd);
208 uloop_fd_add(&proc->log_uloop, ULOOP_EDGE_TRIGGER | ULOOP_READ);
209
210 return 0;
211
212 error:
213 close(pfds[0]);
214 close(pfds[1]);
215 return -1;
216 }
217
218 void
219 netifd_kill_process(struct netifd_process *proc)
220 {
221 if (!proc->uloop.pending)
222 return;
223
224 kill(proc->uloop.pid, SIGTERM);
225 netifd_delete_process(proc);
226 }
227
228 void
229 netifd_fd_add(struct netifd_fd *fd)
230 {
231 list_add_tail(&fd->list, &fds);
232 }
233
234 void
235 netifd_fd_delete(struct netifd_fd *fd)
236 {
237 list_del(&fd->list);
238 }
239
240 static void netifd_do_restart(struct uloop_timeout *timeout)
241 {
242 execvp(global_argv[0], global_argv);
243 }
244
245 static void netifd_do_reload(struct uloop_timeout *timeout)
246 {
247 config_init_interfaces(NULL);
248 }
249
250 static struct uloop_timeout main_timer;
251
252 void netifd_reload(void)
253 {
254 main_timer.cb = netifd_do_reload;
255 uloop_timeout_set(&main_timer, 100);
256 }
257
258 void netifd_restart(void)
259 {
260 main_timer.cb = netifd_do_restart;
261 interface_set_down(NULL);
262 uloop_timeout_set(&main_timer, 1000);
263 }
264
265 static int usage(const char *progname)
266 {
267 fprintf(stderr, "Usage: %s [options]\n"
268 "Options:\n"
269 " -d <mask>: Mask for debug messages\n"
270 " -s <path>: Path to the ubus socket\n"
271 " -p <path>: Path to netifd addons (default: %s)\n"
272 " -h <path>: Path to the hotplug script\n"
273 " -r <path>: Path to resolv.conf\n"
274 " -l <level>: Log output level (default: %d)\n"
275 " -S: Use stderr instead of syslog for log messages\n"
276 " (default: "DEFAULT_HOTPLUG_PATH")\n"
277 "\n", progname, main_path, DEFAULT_LOG_LEVEL);
278
279 return 1;
280 }
281
282 static void
283 netifd_handle_signal(int signo)
284 {
285 uloop_end();
286 }
287
288 static void
289 netifd_setup_signals(void)
290 {
291 struct sigaction s;
292
293 memset(&s, 0, sizeof(s));
294 s.sa_handler = netifd_handle_signal;
295 s.sa_flags = 0;
296 sigaction(SIGINT, &s, NULL);
297 sigaction(SIGTERM, &s, NULL);
298 sigaction(SIGUSR1, &s, NULL);
299 sigaction(SIGUSR2, &s, NULL);
300
301 s.sa_handler = SIG_IGN;
302 sigaction(SIGPIPE, &s, NULL);
303 }
304
305 static void
306 netifd_kill_processes(void)
307 {
308 struct netifd_process *proc, *tmp;
309
310 list_for_each_entry_safe(proc, tmp, &process_list, list)
311 netifd_kill_process(proc);
312 }
313
314 int main(int argc, char **argv)
315 {
316 const char *socket = NULL;
317 int ch;
318
319 global_argv = argv;
320
321 while ((ch = getopt(argc, argv, "d:s:p:h:r:l:S")) != -1) {
322 switch(ch) {
323 case 'd':
324 debug_mask = strtoul(optarg, NULL, 0);
325 break;
326 case 's':
327 socket = optarg;
328 break;
329 case 'p':
330 main_path = optarg;
331 break;
332 case 'h':
333 hotplug_cmd_path = optarg;
334 break;
335 case 'r':
336 resolv_conf = optarg;
337 break;
338 case 'l':
339 log_level = atoi(optarg);
340 if (log_level >= ARRAY_SIZE(log_class))
341 log_level = ARRAY_SIZE(log_class) - 1;
342 break;
343 #ifndef DUMMY_MODE
344 case 'S':
345 use_syslog = false;
346 break;
347 #endif
348 default:
349 return usage(argv[0]);
350 }
351 }
352
353 if (use_syslog)
354 openlog("netifd", 0, LOG_DAEMON);
355
356 netifd_setup_signals();
357 if (netifd_ubus_init(socket) < 0) {
358 fprintf(stderr, "Failed to connect to ubus\n");
359 return 1;
360 }
361
362 if (system_init()) {
363 fprintf(stderr, "Failed to initialize system control\n");
364 return 1;
365 }
366
367 config_init_interfaces(NULL);
368
369 uloop_run();
370 netifd_kill_processes();
371
372 netifd_ubus_done();
373
374 if (use_syslog)
375 closelog();
376
377 return 0;
378 }