void check_errors_in_children(int signo) { int status; if (!signo) { /* block waiting for any child */ if (wait(&status) < 0) //FIXME: check EINTR? return; /* probably there are no children */ goto check_status; } /* Wait for any child without blocking */ for (;;) { if (wait_any_nohang(&status) < 0) //FIXME: check EINTR? /* wait failed?! I'm confused... */ return; check_status: /*if (WIFEXITED(status) && WEXITSTATUS(status) == 0)*/ /* On Linux, the above can be checked simply as: */ if (status == 0) /* this child exited with 0 */ continue; /* Cannot happen: if (!WIFSIGNALED(status) && !WIFEXITED(status)) ???; */ bb_got_signal = 1; } }
static void handle_SIGCHLD(int status) { /* Actually, 'status' is a signo. We reuse it for other needs */ /* Wait for any child without blocking */ if (wait_any_nohang(&status) < 0) /* wait failed?! I'm confused... */ return; if (WIFEXITED(status) && WEXITSTATUS(status)==0) /* child exited with 0 */ return; /* Cannot happen? if (!WIFSIGNALED(status) && !WIFEXITED(status)) return; */ child_error = 1; }
static void sig_child_handler(int sig ATTRIBUTE_UNUSED) { int wstat; int pid; while ((pid = wait_any_nohang(&wstat)) > 0) { if (max_per_host) ipsvd_perhost_remove(pid); if (cnum) cnum--; if (verbose) print_waitstat(pid, wstat); } if (verbose) connection_status(); }
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 = 0; int wstat; int curdir; pid_t pid; unsigned deadline; unsigned now; unsigned stampcheck; int i; int need_rescan = 1; char *opt_s_argv[3]; INIT_G(); opt_complementary = "-1"; opt_s_argv[0] = NULL; opt_s_argv[2] = NULL; getopt32(argv, "Ps:", &opt_s_argv[0]); argv += optind; bb_signals(0 | (1 << SIGTERM) | (1 << SIGHUP) /* For busybox's init, SIGTERM == reboot, * SIGUSR1 == halt * SIGUSR2 == poweroff * so we need to intercept SIGUSRn 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. */ | (getpid() == 1 ? ((1 << SIGUSR1) | (1 << SIGUSR2)) : 0) , record_signo); svdir = *argv++; #if ENABLE_FEATURE_RUNSVDIR_LOG /* setup log */ if (*argv) { rplog = *argv; rploglen = strlen(rplog); if (rploglen < 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(); for (;;) { /* collect children */ for (;;) { pid = wait_any_nohang(&wstat); 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 deadline = (need_rescan ? 1 : 5); sig_block(SIGCHLD); #if ENABLE_FEATURE_RUNSVDIR_LOG if (rplog) poll(pfd, 1, deadline*1000); else #endif sleep(deadline); sig_unblock(SIGCHLD); #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; i < rploglen; i++) rplog[i-1] = rplog[i]; rplog[rploglen-1] = ch; } } #endif if (!bb_got_signal) continue; /* -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]) { /* Single parameter: signal# */ opt_s_argv[1] = utoa(bb_got_signal); pid = spawn(opt_s_argv); if (pid > 0) { /* Remembering to wait for _any_ children, * not just pid */ while (wait(NULL) != pid) continue; } } if (bb_got_signal == 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 (getpid() != 1) return (SIGHUP == bb_got_signal) ? 111 : EXIT_SUCCESS; /* init continues to monitor services forever */ bb_got_signal = 0; } /* for (;;) */ }
int runsv_main(int argc UNUSED_PARAM, char **argv) { struct stat s; int fd; int r; char buf[256]; INIT_G(); dir = single_argv(argv); xpiped_pair(selfpipe); close_on_exec_on(selfpipe.rd); close_on_exec_on(selfpipe.wr); ndelay_on(selfpipe.rd); ndelay_on(selfpipe.wr); sig_block(SIGCHLD); bb_signals_recursive_norestart(1 << SIGCHLD, s_child); sig_block(SIGTERM); bb_signals_recursive_norestart(1 << SIGTERM, s_term); xchdir(dir); /* bss: svd[0].pid = 0; */ if (S_DOWN) svd[0].state = S_DOWN; /* otherwise already 0 (bss) */ if (C_NOOP) svd[0].ctrl = C_NOOP; if (W_UP) svd[0].sd_want = W_UP; /* bss: svd[0].islog = 0; */ /* bss: svd[1].pid = 0; */ gettimeofday_ns(&svd[0].start); if (stat("down", &s) != -1) svd[0].sd_want = W_DOWN; if (stat("log", &s) == -1) { if (errno != ENOENT) warn_cannot("stat ./log"); } else { if (!S_ISDIR(s.st_mode)) { errno = 0; warn_cannot("stat log/down: log is not a directory"); } else { haslog = 1; svd[1].state = S_DOWN; svd[1].ctrl = C_NOOP; svd[1].sd_want = W_UP; svd[1].islog = 1; gettimeofday_ns(&svd[1].start); if (stat("log/down", &s) != -1) svd[1].sd_want = W_DOWN; xpiped_pair(logpipe); close_on_exec_on(logpipe.rd); close_on_exec_on(logpipe.wr); } } if (mkdir("supervise", 0700) == -1) { r = readlink("supervise", buf, sizeof(buf)); if (r != -1) { if (r == sizeof(buf)) fatal2x_cannot("readlink ./supervise", ": name too long"); buf[r] = 0; mkdir(buf, 0700); } else { if ((errno != ENOENT) && (errno != EINVAL)) fatal_cannot("readlink ./supervise"); } } svd[0].fdlock = xopen3("log/supervise/lock"+4, O_WRONLY|O_NDELAY|O_APPEND|O_CREAT, 0600); if (flock(svd[0].fdlock, LOCK_EX | LOCK_NB) == -1) fatal_cannot("lock supervise/lock"); close_on_exec_on(svd[0].fdlock); if (haslog) { if (mkdir("log/supervise", 0700) == -1) { r = readlink("log/supervise", buf, 256); if (r != -1) { if (r == 256) fatal2x_cannot("readlink ./log/supervise", ": name too long"); buf[r] = 0; fd = xopen(".", O_RDONLY|O_NDELAY); xchdir("./log"); mkdir(buf, 0700); if (fchdir(fd) == -1) fatal_cannot("change back to service directory"); close(fd); } else { if ((errno != ENOENT) && (errno != EINVAL)) fatal_cannot("readlink ./log/supervise"); } } svd[1].fdlock = xopen3("log/supervise/lock", O_WRONLY|O_NDELAY|O_APPEND|O_CREAT, 0600); if (flock(svd[1].fdlock, LOCK_EX) == -1) fatal_cannot("lock log/supervise/lock"); close_on_exec_on(svd[1].fdlock); } mkfifo("log/supervise/control"+4, 0600); svd[0].fdcontrol = xopen("log/supervise/control"+4, O_RDONLY|O_NDELAY); close_on_exec_on(svd[0].fdcontrol); svd[0].fdcontrolwrite = xopen("log/supervise/control"+4, O_WRONLY|O_NDELAY); close_on_exec_on(svd[0].fdcontrolwrite); update_status(&svd[0]); if (haslog) { mkfifo("log/supervise/control", 0600); svd[1].fdcontrol = xopen("log/supervise/control", O_RDONLY|O_NDELAY); close_on_exec_on(svd[1].fdcontrol); svd[1].fdcontrolwrite = xopen("log/supervise/control", O_WRONLY|O_NDELAY); close_on_exec_on(svd[1].fdcontrolwrite); update_status(&svd[1]); } mkfifo("log/supervise/ok"+4, 0600); fd = xopen("log/supervise/ok"+4, O_RDONLY|O_NDELAY); close_on_exec_on(fd); if (haslog) { mkfifo("log/supervise/ok", 0600); fd = xopen("log/supervise/ok", O_RDONLY|O_NDELAY); close_on_exec_on(fd); } for (;;) { struct pollfd x[3]; unsigned deadline; char ch; if (haslog) if (!svd[1].pid && svd[1].sd_want == W_UP) startservice(&svd[1]); if (!svd[0].pid) if (svd[0].sd_want == W_UP || svd[0].state == S_FINISH) startservice(&svd[0]); x[0].fd = selfpipe.rd; x[0].events = POLLIN; x[1].fd = svd[0].fdcontrol; x[1].events = POLLIN; /* x[2] is used only if haslog == 1 */ x[2].fd = svd[1].fdcontrol; x[2].events = POLLIN; sig_unblock(SIGTERM); sig_unblock(SIGCHLD); poll(x, 2 + haslog, 3600*1000); sig_block(SIGTERM); sig_block(SIGCHLD); while (read(selfpipe.rd, &ch, 1) == 1) continue; for (;;) { pid_t child; int wstat; child = wait_any_nohang(&wstat); if (!child) break; if ((child == -1) && (errno != EINTR)) break; if (child == svd[0].pid) { svd[0].wstat = wstat; svd[0].pid = 0; pidchanged = 1; svd[0].ctrl &= ~C_TERM; if (svd[0].state != S_FINISH) { fd = open("finish", O_RDONLY|O_NDELAY); if (fd != -1) { close(fd); svd[0].state = S_FINISH; update_status(&svd[0]); continue; } } svd[0].state = S_DOWN; deadline = svd[0].start.tv_sec + 1; gettimeofday_ns(&svd[0].start); update_status(&svd[0]); if (LESS(svd[0].start.tv_sec, deadline)) sleep(1); } if (haslog) { if (child == svd[1].pid) { svd[0].wstat = wstat; svd[1].pid = 0; pidchanged = 1; svd[1].state = S_DOWN; svd[1].ctrl &= ~C_TERM; deadline = svd[1].start.tv_sec + 1; gettimeofday_ns(&svd[1].start); update_status(&svd[1]); if (LESS(svd[1].start.tv_sec, deadline)) sleep(1); } } } /* for (;;) */ if (read(svd[0].fdcontrol, &ch, 1) == 1) ctrl(&svd[0], ch); if (haslog) if (read(svd[1].fdcontrol, &ch, 1) == 1) ctrl(&svd[1], ch); if (sigterm) { ctrl(&svd[0], 'x'); sigterm = 0; } if (svd[0].sd_want == W_EXIT && svd[0].state == S_DOWN) { if (svd[1].pid == 0) _exit(EXIT_SUCCESS); if (svd[1].sd_want != W_EXIT) { svd[1].sd_want = W_EXIT; /* stopservice(&svd[1]); */ update_status(&svd[1]); close(logpipe.wr); close(logpipe.rd); } } } /* for (;;) */ /* not reached */ return 0; }