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- /*
- 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 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 (;;) */
- }
|