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