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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 | /* Copyright (c) 2001-2006, Gerrit Pape All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. The name of the author may not be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* Busyboxed by Denys Vlasenko <vda.linux@googlemail.com> */ //config:config RUNSVDIR //config: bool "runsvdir (6.6 kb)" //config: default y //config: help //config: runsvdir starts a runsv process for each subdirectory, or symlink to //config: a directory, in the services directory dir, up to a limit of 1000 //config: subdirectories, and restarts a runsv process if it terminates. //config: //config:config FEATURE_RUNSVDIR_LOG //config: bool "Enable scrolling argument log" //config: depends on RUNSVDIR //config: default n //config: help //config: Enable feature where second parameter of runsvdir holds last error //config: message (viewable via top/ps). Otherwise (feature is off //config: or no parameter), error messages go to stderr only. //applet:IF_RUNSVDIR(APPLET(runsvdir, BB_DIR_USR_BIN, BB_SUID_DROP)) //kbuild:lib-$(CONFIG_RUNSVDIR) += runsvdir.o //usage:#define runsvdir_trivial_usage //usage: "[-P] [-s SCRIPT] DIR" //usage:#define runsvdir_full_usage "\n\n" //usage: "Start a runsv process for each subdirectory. If it exits, restart it.\n" //usage: "\n -P Put each runsv in a new session" //usage: "\n -s SCRIPT Run SCRIPT <signo> after signal is processed" #include <sys/file.h> #include "libbb.h" #include "common_bufsiz.h" #include "runit_lib.h" #define MAXSERVICES 1000 /* Should be not needed - all dirs are on same FS, right? */ #define CHECK_DEVNO_TOO 0 struct service { #if CHECK_DEVNO_TOO dev_t dev; #endif ino_t ino; pid_t pid; smallint isgone; }; struct globals { struct service *sv; char *svdir; int svnum; #if ENABLE_FEATURE_RUNSVDIR_LOG char *rplog; struct fd_pair logpipe; struct pollfd pfd[1]; unsigned stamplog; #endif } FIX_ALIASING; #define G (*(struct globals*)bb_common_bufsiz1) #define sv (G.sv ) #define svdir (G.svdir ) #define svnum (G.svnum ) #define rplog (G.rplog ) #define logpipe (G.logpipe ) #define pfd (G.pfd ) #define stamplog (G.stamplog ) #define INIT_G() do { setup_common_bufsiz(); } while (0) static void fatal2_cannot(const char *m1, const char *m2) { bb_perror_msg_and_die("%s: fatal: can't %s%s", svdir, m1, m2); /* was exiting 100 */ } static void warn3x(const char *m1, const char *m2, const char *m3) { bb_error_msg("%s: warning: %s%s%s", svdir, m1, m2, m3); } static void warn2_cannot(const char *m1, const char *m2) { warn3x("can't ", m1, m2); } #if ENABLE_FEATURE_RUNSVDIR_LOG static void warnx(const char *m1) { warn3x(m1, "", ""); } #endif /* inlining + vfork -> bigger code */ static NOINLINE pid_t runsv(const char *name) { pid_t pid; /* If we got signaled, stop spawning children at once! */ if (bb_got_signal) return 0; pid = vfork(); if (pid == -1) { warn2_cannot("vfork", ""); return 0; } if (pid == 0) { /* child */ if (option_mask32 & 1) /* -P option? */ setsid(); /* man execv: * "Signals set to be caught by the calling process image * shall be set to the default action in the new process image." * Therefore, we do not need this: */ #if 0 bb_signals(0 | (1 << SIGHUP) | (1 << SIGTERM) , SIG_DFL); #endif execlp("runsv", "runsv", name, (char *) NULL); fatal2_cannot("start runsv ", name); } return pid; } /* gcc 4.3.0 does better with NOINLINE */ static NOINLINE int do_rescan(void) { DIR *dir; struct dirent *d; int i; struct stat s; int need_rescan = 0; dir = opendir("."); if (!dir) { warn2_cannot("open directory ", svdir); return 1; /* need to rescan again soon */ } for (i = 0; i < svnum; i++) sv[i].isgone = 1; while (1) { errno = 0; d = readdir(dir); if (!d) break; if (d->d_name[0] == '.') continue; if (stat(d->d_name, &s) == -1) { warn2_cannot("stat ", d->d_name); continue; } if (!S_ISDIR(s.st_mode)) continue; /* Do we have this service listed already? */ for (i = 0; i < svnum; i++) { if (sv[i].ino == s.st_ino #if CHECK_DEVNO_TOO && sv[i].dev == s.st_dev #endif ) { if (sv[i].pid == 0) /* restart if it has died */ goto run_ith_sv; sv[i].isgone = 0; /* "we still see you" */ goto next_dentry; } } { /* Not found, make new service */ struct service *svnew = realloc(sv, (i+1) * sizeof(*sv)); if (!svnew) { warn2_cannot("start runsv ", d->d_name); need_rescan = 1; continue; } sv = svnew; svnum++; #if CHECK_DEVNO_TOO sv[i].dev = s.st_dev; #endif sv[i].ino = s.st_ino; run_ith_sv: sv[i].pid = runsv(d->d_name); sv[i].isgone = 0; } next_dentry: ; } i = errno; closedir(dir); if (i) { /* readdir failed */ warn2_cannot("read directory ", svdir); return 1; /* need to rescan again soon */ } /* Send SIGTERM to runsv whose directories * were no longer found (-> must have been removed) */ for (i = 0; i < svnum; i++) { if (!sv[i].isgone) continue; if (sv[i].pid) kill(sv[i].pid, SIGTERM); svnum--; sv[i] = sv[svnum]; i--; /* so that we don't skip new sv[i] (bug was here!) */ } return need_rescan; } int runsvdir_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int runsvdir_main(int argc UNUSED_PARAM, char **argv) { struct stat s; dev_t last_dev = last_dev; /* for gcc */ ino_t last_ino = last_ino; /* for gcc */ time_t last_mtime; int curdir; unsigned stampcheck; int i; int need_rescan; bool i_am_init; char *opt_s_argv[3]; INIT_G(); opt_s_argv[0] = NULL; opt_s_argv[2] = NULL; getopt32(argv, "^" "Ps:" "\0" "-1", &opt_s_argv[0]); argv += optind; i_am_init = (getpid() == 1); bb_signals(0 | (1 << SIGTERM) | (1 << SIGHUP) /* For busybox's init, SIGTERM == reboot, * SIGUSR1 == halt, * SIGUSR2 == poweroff, * Ctlr-ALt-Del sends SIGINT to init, * so we need to intercept SIGUSRn and SIGINT too. * Note that we do not implement actual reboot * (killall(TERM) + umount, etc), we just pause * respawing and avoid exiting (-> making kernel oops). * The user is responsible for the rest. */ | (i_am_init ? ((1 << SIGUSR1) | (1 << SIGUSR2) | (1 << SIGINT)) : 0) , record_signo); svdir = *argv++; #if ENABLE_FEATURE_RUNSVDIR_LOG /* setup log */ if (*argv) { rplog = *argv; if (strlen(rplog) < 7) { warnx("log must have at least seven characters"); } else if (piped_pair(logpipe)) { warnx("can't create pipe for log"); } else { close_on_exec_on(logpipe.rd); close_on_exec_on(logpipe.wr); ndelay_on(logpipe.rd); ndelay_on(logpipe.wr); if (dup2(logpipe.wr, 2) == -1) { warnx("can't set filedescriptor for log"); } else { pfd[0].fd = logpipe.rd; pfd[0].events = POLLIN; stamplog = monotonic_sec(); goto run; } } rplog = NULL; warnx("log service disabled"); } run: #endif curdir = open(".", O_RDONLY|O_NDELAY); if (curdir == -1) fatal2_cannot("open current directory", ""); close_on_exec_on(curdir); stampcheck = monotonic_sec(); need_rescan = 1; last_mtime = 0; for (;;) { unsigned now; unsigned sig; /* collect children */ for (;;) { pid_t pid = wait_any_nohang(NULL); if (pid <= 0) break; for (i = 0; i < svnum; i++) { if (pid == sv[i].pid) { /* runsv has died */ sv[i].pid = 0; need_rescan = 1; } } } now = monotonic_sec(); if ((int)(now - stampcheck) >= 0) { /* wait at least a second */ stampcheck = now + 1; if (stat(svdir, &s) != -1) { if (need_rescan || s.st_mtime != last_mtime || s.st_ino != last_ino || s.st_dev != last_dev ) { /* svdir modified */ if (chdir(svdir) != -1) { last_mtime = s.st_mtime; last_dev = s.st_dev; last_ino = s.st_ino; /* if the svdir changed this very second, wait until the * next second, because we won't be able to detect more * changes within this second */ while (time(NULL) == last_mtime) usleep(100000); need_rescan = do_rescan(); while (fchdir(curdir) == -1) { warn2_cannot("change directory, pausing", ""); sleep(5); } } else { warn2_cannot("change directory to ", svdir); } } } else { warn2_cannot("stat ", svdir); } } #if ENABLE_FEATURE_RUNSVDIR_LOG if (rplog) { if ((int)(now - stamplog) >= 0) { write(logpipe.wr, ".", 1); stamplog = now + 900; } } pfd[0].revents = 0; #endif { unsigned deadline = (need_rescan ? 1 : 5); #if ENABLE_FEATURE_RUNSVDIR_LOG if (rplog) poll(pfd, 1, deadline*1000); else #endif sleep(deadline); } #if ENABLE_FEATURE_RUNSVDIR_LOG if (pfd[0].revents & POLLIN) { char ch; while (read(logpipe.rd, &ch, 1) > 0) { if (ch < ' ') ch = ' '; for (i = 6; rplog[i] != '\0'; i++) rplog[i-1] = rplog[i]; rplog[i-1] = ch; } } #endif sig = bb_got_signal; if (!sig) continue; bb_got_signal = 0; /* -s SCRIPT: useful if we are init. * In this case typically script never returns, * it halts/powers off/reboots the system. */ if (opt_s_argv[0]) { pid_t pid; /* Single parameter: signal# */ opt_s_argv[1] = utoa(sig); pid = spawn(opt_s_argv); if (pid > 0) { /* Remembering to wait for _any_ children, * not just pid */ while (wait(NULL) != pid) continue; } } if (sig == SIGHUP) { for (i = 0; i < svnum; i++) if (sv[i].pid) kill(sv[i].pid, SIGTERM); } /* SIGHUP or SIGTERM (or SIGUSRn if we are init) */ /* Exit unless we are init */ if (!i_am_init) return (SIGHUP == sig) ? 111 : EXIT_SUCCESS; /* init continues to monitor services forever */ } /* for (;;) */ } |