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
+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,
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
-/* Busyboxed by Denis Vlasenko <vda.linux@googlemail.com> */
-/* TODO: depends on runit_lib.c - review and reduce/eliminate */
+/* Busyboxed by Denys Vlasenko <vda.linux@googlemail.com> */
+
+//config:config RUNSVDIR
+//config: bool "runsvdir (6.3 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/poll.h>
#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;
};
-static struct service *sv;
-static char *svdir;
-static int svnum;
-static char *rplog;
-static int rploglen;
-static int logpipe[2];
-static struct pollfd pfd[1];
-static unsigned stamplog;
-static smallint check = 1;
-static smallint exitsoon;
-static smallint set_pgrp;
+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: cannot %s%s", svdir, m1, 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)
}
static void warn2_cannot(const char *m1, const char *m2)
{
- warn3x("cannot ", m1, m2);
+ warn3x("can't ", m1, m2);
}
+#if ENABLE_FEATURE_RUNSVDIR_LOG
static void warnx(const char *m1)
{
warn3x(m1, "", "");
}
+#endif
-static void s_term(int sig_no)
-{
- exitsoon = 1;
-}
-static void s_hangup(int sig_no)
-{
- exitsoon = 2;
-}
-
-static void runsv(int no, const char *name)
+/* inlining + vfork -> bigger code */
+static NOINLINE pid_t runsv(const char *name)
{
pid_t pid;
- char *prog[3];
- prog[0] = (char*)"runsv";
- prog[1] = (char*)name;
- prog[2] = NULL;
+ /* If we got signaled, stop spawning children at once! */
+ if (bb_got_signal)
+ return 0;
pid = vfork();
-
if (pid == -1) {
warn2_cannot("vfork", "");
- return;
+ return 0;
}
if (pid == 0) {
/* child */
- if (set_pgrp)
+ if (option_mask32 & 1) /* -P option? */
setsid();
- signal(SIGHUP, SIG_DFL);
- signal(SIGTERM, SIG_DFL);
- execvp(prog[0], prog);
+/* 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);
}
- sv[no].pid = pid;
+ return pid;
}
-static void runsvdir(void)
+/* gcc 4.3.0 does better with NOINLINE */
+static NOINLINE int do_rescan(void)
{
DIR *dir;
- direntry *d;
+ struct dirent *d;
int i;
struct stat s;
+ int need_rescan = 0;
dir = opendir(".");
if (!dir) {
warn2_cannot("open directory ", svdir);
- return;
+ return 1; /* need to rescan again soon */
}
for (i = 0; i < svnum; i++)
sv[i].isgone = 1;
- errno = 0;
- while ((d = readdir(dir))) {
+
+ 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);
- errno = 0;
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) && (sv[i].dev == s.st_dev)) {
- sv[i].isgone = 0;
- if (!sv[i].pid)
- runsv(i, d->d_name);
- break;
+ 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;
}
}
- if (i == svnum) {
- /* new service */
+ { /* Not found, make new service */
struct service *svnew = realloc(sv, (i+1) * sizeof(*sv));
if (!svnew) {
- warn3x("cannot start runsv ", d->d_name,
- " too many services");
+ warn2_cannot("start runsv ", d->d_name);
+ need_rescan = 1;
continue;
}
sv = svnew;
svnum++;
- memset(&sv[i], 0, sizeof(sv[i]));
- sv[i].ino = s.st_ino;
+#if CHECK_DEVNO_TOO
sv[i].dev = s.st_dev;
- /*sv[i].pid = 0;*/
- /*sv[i].isgone = 0;*/
- runsv(i, d->d_name);
- check = 1;
+#endif
+ sv[i].ino = s.st_ino;
+ run_ith_sv:
+ sv[i].pid = runsv(d->d_name);
+ sv[i].isgone = 0;
}
+ next_dentry: ;
}
- if (errno) {
+ i = errno;
+ closedir(dir);
+ if (i) { /* readdir failed */
warn2_cannot("read directory ", svdir);
- closedir(dir);
- check = 1;
- return;
+ return 1; /* need to rescan again soon */
}
- closedir(dir);
- /* SIGTERM removed runsv's */
+ /* 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);
- sv[i] = sv[--svnum];
- check = 1;
+ svnum--;
+ sv[i] = sv[svnum];
+ i--; /* so that we don't skip new sv[i] (bug was here!) */
}
+ return need_rescan;
}
-static int setup_log(void)
-{
- rploglen = strlen(rplog);
- if (rploglen < 7) {
- warnx("log must have at least seven characters");
- return 0;
- }
- if (pipe(logpipe)) {
- warnx("cannot create pipe for log");
- return -1;
- }
- close_on_exec_on(logpipe[1]);
- close_on_exec_on(logpipe[0]);
- ndelay_on(logpipe[0]);
- ndelay_on(logpipe[1]);
- if (dup2(logpipe[1], 2) == -1) {
- warnx("cannot set filedescriptor for log");
- return -1;
- }
- pfd[0].fd = logpipe[0];
- pfd[0].events = POLLIN;
- stamplog = monotonic_sec();
- return 1;
-}
-
-int runsvdir_main(int argc, char **argv);
-int runsvdir_main(int argc, char **argv)
+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 = 0;
- int wstat;
+ time_t last_mtime;
int curdir;
- int pid;
- unsigned deadline;
- unsigned now;
unsigned stampcheck;
- char ch;
int i;
+ int need_rescan;
+ bool i_am_init;
+ char *opt_s_argv[3];
- argv++;
- if (!*argv)
- bb_show_usage();
- if (argv[0][0] == '-') {
- switch (argv[0][1]) {
- case 'P': set_pgrp = 1;
- case '-': ++argv;
- }
- if (!*argv)
- bb_show_usage();
- }
+ INIT_G();
- sig_catch(SIGTERM, s_term);
- sig_catch(SIGHUP, s_hangup);
+ 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 (argv && *argv) {
+
+#if ENABLE_FEATURE_RUNSVDIR_LOG
+ /* setup log */
+ if (*argv) {
rplog = *argv;
- if (setup_log() != 1) {
- rplog = 0;
- warnx("log service disabled");
+ 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");
}
- curdir = open_read(".");
+ 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 = wait_nohang(&wstat);
+ pid_t pid = wait_any_nohang(NULL);
if (pid <= 0)
break;
for (i = 0; i < svnum; i++) {
if (pid == sv[i].pid) {
- /* runsv has gone */
+ /* runsv has died */
sv[i].pid = 0;
- check = 1;
- break;
+ need_rescan = 1;
}
}
}
stampcheck = now + 1;
if (stat(svdir, &s) != -1) {
- if (check || s.st_mtime != last_mtime
+ if (need_rescan || s.st_mtime != last_mtime
|| s.st_ino != last_ino || s.st_dev != last_dev
) {
/* svdir modified */
last_mtime = s.st_mtime;
last_dev = s.st_dev;
last_ino = s.st_ino;
- check = 0;
- //if (now <= mtime)
- // sleep(1);
- runsvdir();
+ /* 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
+ } else {
warn2_cannot("change directory to ", svdir);
+ }
}
- } else
+ } else {
warn2_cannot("stat ", svdir);
+ }
}
+#if ENABLE_FEATURE_RUNSVDIR_LOG
if (rplog) {
if ((int)(now - stamplog) >= 0) {
- write(logpipe[1], ".", 1);
+ write(logpipe.wr, ".", 1);
stamplog = now + 900;
}
}
-
pfd[0].revents = 0;
- sig_block(SIGCHLD);
- deadline = (check ? 1 : 5);
- if (rplog)
- poll(pfd, 1, deadline*1000);
- else
- sleep(deadline);
- sig_unblock(SIGCHLD);
+#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) {
- while (read(logpipe[0], &ch, 1) > 0) {
- if (ch) {
- for (i = 6; i < rploglen; i++)
- rplog[i-1] = rplog[i];
- rplog[rploglen-1] = ch;
- }
+ 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;
}
}
- switch (exitsoon) {
- case 1:
- _exit(0);
- case 2:
+ if (sig == SIGHUP) {
for (i = 0; i < svnum; i++)
if (sv[i].pid)
kill(sv[i].pid, SIGTERM);
- _exit(111);
}
- }
- /* not reached */
- return 0;
+ /* 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 (;;) */
}
projects / oweals / busybox.git / blobdiff