diff options
author | William Hubbs <w.d.hubbs@gmail.com> | 2018-11-30 11:45:48 -0600 |
---|---|---|
committer | William Hubbs <w.d.hubbs@gmail.com> | 2018-12-02 18:33:25 -0600 |
commit | 77262c359c4aaf15ba00b07cd51f3987ce514769 (patch) | |
tree | 07696411df3f4b178326a648e33e112c20858e69 | |
parent | 7f23e0461d6c6d24f5cfa39b9e404a7ec9cfd9c1 (diff) |
supervise-daemon: add support for a fifo
This will allow us to signal the daemon we are supervising as well as
send other commands to the supervisor in the future.
This fixes #227.
-rw-r--r-- | man/supervise-daemon.8 | 12 | ||||
-rw-r--r-- | src/rc/supervise-daemon.c | 56 |
2 files changed, 61 insertions, 7 deletions
diff --git a/man/supervise-daemon.8 b/man/supervise-daemon.8 index 0da1c5ac..1bf19de0 100644 --- a/man/supervise-daemon.8 +++ b/man/supervise-daemon.8 @@ -57,6 +57,11 @@ .Ar daemon .Fl r , -chroot .Ar chrootpath +.Nm +.Fl s , -signal +.Ar signal +.Fl r , -chroot +.Ar chrootpath .Sh DESCRIPTION .Nm provides a consistent method of starting, stopping and restarting @@ -64,11 +69,8 @@ daemons. If .Fl K , -stop is not provided, then we assume we are starting the daemon. .Nm -only works with daemons which do not fork. Also, it uses its own pid -file, so the daemon should not write a pid file, or the pid file passed -to -.Nm -should not be the one the daemon writes. +only works with daemons which do not fork. If your daemon has options to +tell it not to fork, it should be configured to not fork. .Pp Here are the options to specify the daemon and how it should start or stop: .Bl -tag -width indent diff --git a/src/rc/supervise-daemon.c b/src/rc/supervise-daemon.c index cce0f9db..bfbb85f6 100644 --- a/src/rc/supervise-daemon.c +++ b/src/rc/supervise-daemon.c @@ -68,7 +68,7 @@ static struct pam_conv conv = { NULL, NULL}; const char *applet = NULL; const char *extraopts = NULL; -const char *getoptstring = "A:a:D:d:e:g:H:I:Kk:m:N:p:R:r:Su:1:2:3" \ +const char *getoptstring = "A:a:D:d:e:g:H:I:Kk:m:N:p:R:r:s:Su:1:2:3" \ getoptstring_COMMON; const struct option longopts[] = { { "healthcheck-timer", 1, NULL, 'a'}, @@ -86,6 +86,7 @@ const struct option longopts[] = { { "respawn-period", 1, NULL, 'P'}, { "retry", 1, NULL, 'R'}, { "chroot", 1, NULL, 'r'}, + { "signal", 1, NULL, 's'}, { "start", 0, NULL, 'S'}, { "user", 1, NULL, 'u'}, { "stdout", 1, NULL, '1'}, @@ -109,6 +110,7 @@ const char * const longopts_help[] = { "Set respawn time period", "Retry schedule to use when stopping", "Chroot to this directory", + "Send a signal to the daemon", "Start daemon", "Change the process user", "Redirect stdout to file", @@ -142,6 +144,8 @@ static int respawn_count = 0; static int respawn_delay = 0; static int respawn_max = 10; static int respawn_period = 5; +static char *fifopath = NULL; +static int fifo_fd = 0; static char *pidfile = NULL; static char *svcname = NULL; @@ -439,10 +443,14 @@ static void child_process(char *exec, char **argv) static void supervisor(char *exec, char **argv) { FILE *fp; + char buf[2048]; + char cmd[2048]; + int count; int health_status; int healthcheck_respawn; int i; int nkilled; + int sig_send; pid_t health_pid; pid_t wait_pid; sigset_t old_signals; @@ -489,9 +497,29 @@ static void supervisor(char *exec, char **argv) alarm(healthcheckdelay); else if (healthchecktimer) alarm(healthchecktimer); + fifo_fd = open(fifopath, O_RDONLY |O_NONBLOCK); while (!exiting) { healthcheck_respawn = 0; - wait_pid = waitpid(child_pid, &i, 0); + wait_pid = waitpid(child_pid, &i, WNOHANG); + memset(buf, 0, sizeof(buf)); + if (fifo_fd >= 0) { + count = read(fifo_fd, buf, sizeof(buf) - 1); + if (count != -1) + buf[count] = 0; + } + if (strlen(buf) > 0) { + syslog(LOG_DEBUG, "Received %s from fifo", buf); + if (strncasecmp(buf, "sig", 3) == 0) { + if ((sscanf(buf, "%s %d", cmd, &sig_send) == 2) + && (sig_send >= 0 && sig_send < NSIG)) { + syslog(LOG_INFO, "Sending signal %d to %d", sig_send, + child_pid); + if (kill(child_pid, sig_send) == -1) + syslog(LOG_ERR, "Unable to send signal %d to %d", + sig_send, child_pid); + } + } + } if (do_healthcheck) { do_healthcheck = 0; alarm(0); @@ -578,6 +606,8 @@ static void supervisor(char *exec, char **argv) if (pidfile && exists(pidfile)) unlink(pidfile); + if (fifopath && exists(fifopath)) + unlink(fifopath); if (svcname) { rc_service_daemon_set(svcname, exec, (const char *const *)argv, pidfile, false); @@ -595,6 +625,7 @@ int main(int argc, char **argv) bool start = false; bool stop = false; bool reexec = false; + bool sendsig = false; char *exec = NULL; char *retry = NULL; int sig = SIGTERM; @@ -700,6 +731,10 @@ int main(int argc, char **argv) eerrorx("Invalid respawn-period value '%s'", optarg); break; + case 's': /* --signal */ + sig = parse_signal(applet, optarg); + sendsig = true; + break; case 'S': /* --start */ start = true; break; @@ -818,6 +853,10 @@ int main(int argc, char **argv) umask(numask); xasprintf(&pidfile, "/var/run/supervise-%s.pid", svcname); + xasprintf(&fifopath, "%s/supervise-%s.ctl", RC_SVCDIR, svcname); + if (mkfifo(fifopath, 0600) == -1 && errno != EEXIST) + eerrorx("%s: unable to create control fifo: %s", + applet, strerror(errno)); if (reexec) { str = rc_service_value_get(svcname, "argc"); @@ -989,5 +1028,18 @@ int main(int argc, char **argv) rc_service_mark(svcname, RC_SERVICE_STOPPED); } exit(EXIT_SUCCESS); + } else if (sendsig) { + fifo_fd = open(fifopath, O_WRONLY |O_NONBLOCK); + if (fifo_fd < 0) + eerrorx("%s: unable to open control fifo %s", applet, strerror(errno)); + xasprintf(&str, "sig %d", sig); + x = write(fifo_fd, str, strlen(str)); + if (x == -1) { + free(tmp); + eerrorx("%s: error writing to control fifo: %s", applet, + strerror(errno)); + } + free(tmp); + exit(EXIT_SUCCESS); } } |