815 lines
22 KiB
C
815 lines
22 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-3-Clause
|
|
*
|
|
* Copyright (c) 1999 Berkeley Software Design, Inc. 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. Berkeley Software Design Inc's name may not be used to endorse or
|
|
* promote products derived from this software without specific prior
|
|
* written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``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 BERKELEY SOFTWARE DESIGN INC 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.
|
|
*
|
|
* From BSDI: daemon.c,v 1.2 1996/08/15 01:11:09 jch Exp
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/wait.h>
|
|
|
|
#include <fcntl.h>
|
|
#include <err.h>
|
|
#include <errno.h>
|
|
#include <getopt.h>
|
|
#include <libutil.h>
|
|
#include <login_cap.h>
|
|
#include <paths.h>
|
|
#include <pwd.h>
|
|
#include <signal.h>
|
|
#include <stdio.h>
|
|
#include <stdbool.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <strings.h>
|
|
#define SYSLOG_NAMES
|
|
#include <syslog.h>
|
|
#include <time.h>
|
|
#include <assert.h>
|
|
|
|
#define LBUF_SIZE 4096
|
|
|
|
struct daemon_state {
|
|
sigset_t mask_orig;
|
|
sigset_t mask_read;
|
|
sigset_t mask_term;
|
|
sigset_t mask_susp;
|
|
int pipe_fd[2];
|
|
char **argv;
|
|
const char *child_pidfile;
|
|
const char *parent_pidfile;
|
|
const char *output_filename;
|
|
const char *syslog_tag;
|
|
const char *title;
|
|
const char *user;
|
|
struct pidfh *parent_pidfh;
|
|
struct pidfh *child_pidfh;
|
|
int keep_cur_workdir;
|
|
int restart_delay;
|
|
int stdmask;
|
|
int syslog_priority;
|
|
int syslog_facility;
|
|
int keep_fds_open;
|
|
int output_fd;
|
|
bool supervision_enabled;
|
|
bool child_eof;
|
|
bool restart_enabled;
|
|
bool syslog_enabled;
|
|
bool log_reopen;
|
|
};
|
|
|
|
static void setup_signals(struct daemon_state *);
|
|
static void restrict_process(const char *);
|
|
static void handle_term(int);
|
|
static void handle_chld(int);
|
|
static void handle_hup(int);
|
|
static int open_log(const char *);
|
|
static void reopen_log(struct daemon_state *);
|
|
static bool listen_child(int, struct daemon_state *);
|
|
static int get_log_mapping(const char *, const CODE *);
|
|
static void open_pid_files(struct daemon_state *);
|
|
static void do_output(const unsigned char *, size_t, struct daemon_state *);
|
|
static void daemon_sleep(time_t, long);
|
|
static void daemon_state_init(struct daemon_state *);
|
|
static void daemon_eventloop(struct daemon_state *);
|
|
static void daemon_terminate(struct daemon_state *);
|
|
|
|
static volatile sig_atomic_t terminate = 0;
|
|
static volatile sig_atomic_t child_gone = 0;
|
|
static volatile sig_atomic_t pid = 0;
|
|
static volatile sig_atomic_t do_log_reopen = 0;
|
|
|
|
static const char shortopts[] = "+cfHSp:P:ru:o:s:l:t:m:R:T:h";
|
|
|
|
static const struct option longopts[] = {
|
|
{ "change-dir", no_argument, NULL, 'c' },
|
|
{ "close-fds", no_argument, NULL, 'f' },
|
|
{ "sighup", no_argument, NULL, 'H' },
|
|
{ "syslog", no_argument, NULL, 'S' },
|
|
{ "output-file", required_argument, NULL, 'o' },
|
|
{ "output-mask", required_argument, NULL, 'm' },
|
|
{ "child-pidfile", required_argument, NULL, 'p' },
|
|
{ "supervisor-pidfile", required_argument, NULL, 'P' },
|
|
{ "restart", no_argument, NULL, 'r' },
|
|
{ "restart-delay", required_argument, NULL, 'R' },
|
|
{ "title", required_argument, NULL, 't' },
|
|
{ "user", required_argument, NULL, 'u' },
|
|
{ "syslog-priority", required_argument, NULL, 's' },
|
|
{ "syslog-facility", required_argument, NULL, 'l' },
|
|
{ "syslog-tag", required_argument, NULL, 'T' },
|
|
{ "help", no_argument, NULL, 'h' },
|
|
{ NULL, 0, NULL, 0 }
|
|
};
|
|
|
|
static _Noreturn void
|
|
usage(int exitcode)
|
|
{
|
|
(void)fprintf(stderr,
|
|
"usage: daemon [-cfHrS] [-p child_pidfile] [-P supervisor_pidfile]\n"
|
|
" [-u user] [-o output_file] [-t title]\n"
|
|
" [-l syslog_facility] [-s syslog_priority]\n"
|
|
" [-T syslog_tag] [-m output_mask] [-R restart_delay_secs]\n"
|
|
"command arguments ...\n");
|
|
|
|
(void)fprintf(stderr,
|
|
" --change-dir -c Change the current working directory to root\n"
|
|
" --close-fds -f Set stdin, stdout, stderr to /dev/null\n"
|
|
" --sighup -H Close and re-open output file on SIGHUP\n"
|
|
" --syslog -S Send output to syslog\n"
|
|
" --output-file -o <file> Append output of the child process to file\n"
|
|
" --output-mask -m <mask> What to send to syslog/file\n"
|
|
" 1=stdout, 2=stderr, 3=both\n"
|
|
" --child-pidfile -p <file> Write PID of the child process to file\n"
|
|
" --supervisor-pidfile -P <file> Write PID of the supervisor process to file\n"
|
|
" --restart -r Restart child if it terminates (1 sec delay)\n"
|
|
" --restart-delay -R <N> Restart child if it terminates after N sec\n"
|
|
" --title -t <title> Set the title of the supervisor process\n"
|
|
" --user -u <user> Drop privileges, run as given user\n"
|
|
" --syslog-priority -s <prio> Set syslog priority\n"
|
|
" --syslog-facility -l <flty> Set syslog facility\n"
|
|
" --syslog-tag -T <tag> Set syslog tag\n"
|
|
" --help -h Show this help\n");
|
|
|
|
exit(exitcode);
|
|
}
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
char *p = NULL;
|
|
int ch = 0;
|
|
struct daemon_state state;
|
|
|
|
daemon_state_init(&state);
|
|
|
|
/*
|
|
* Supervision mode is enabled if one of the following options are used:
|
|
* --child-pidfile -p
|
|
* --supervisor-pidfile -P
|
|
* --restart -r / --restart-delay -R
|
|
* --syslog -S
|
|
* --syslog-facility -l
|
|
* --syslog-priority -s
|
|
* --syslog-tag -T
|
|
*
|
|
* In supervision mode daemon executes the command in a forked process
|
|
* and observes the child by waiting for SIGCHILD. In supervision mode
|
|
* daemon must never exit before the child, this is necessary to prevent
|
|
* orphaning the child and leaving a stale pid file.
|
|
* To achieve this daemon catches SIGTERM and
|
|
* forwards it to the child, expecting to get SIGCHLD eventually.
|
|
*/
|
|
while ((ch = getopt_long(argc, argv, shortopts, longopts, NULL)) != -1) {
|
|
switch (ch) {
|
|
case 'c':
|
|
state.keep_cur_workdir = 0;
|
|
break;
|
|
case 'f':
|
|
state.keep_fds_open = 0;
|
|
break;
|
|
case 'H':
|
|
state.log_reopen = true;
|
|
break;
|
|
case 'l':
|
|
state.syslog_facility = get_log_mapping(optarg,
|
|
facilitynames);
|
|
if (state.syslog_facility == -1) {
|
|
errx(5, "unrecognized syslog facility");
|
|
}
|
|
state.syslog_enabled = true;
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 'm':
|
|
state.stdmask = strtol(optarg, &p, 10);
|
|
if (p == optarg || state.stdmask < 0 || state.stdmask > 3) {
|
|
errx(6, "unrecognized listening mask");
|
|
}
|
|
break;
|
|
case 'o':
|
|
state.output_filename = optarg;
|
|
/*
|
|
* TODO: setting output filename doesn't have to turn
|
|
* the supervision mode on. For non-supervised mode
|
|
* daemon could open the specified file and set it's
|
|
* descriptor as both stderr and stout before execve()
|
|
*/
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 'p':
|
|
state.child_pidfile = optarg;
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 'P':
|
|
state.parent_pidfile = optarg;
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 'r':
|
|
state.restart_enabled = true;
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 'R':
|
|
state.restart_enabled = true;
|
|
state.restart_delay = strtol(optarg, &p, 0);
|
|
if (p == optarg || state.restart_delay < 1) {
|
|
errx(6, "invalid restart delay");
|
|
}
|
|
break;
|
|
case 's':
|
|
state.syslog_priority = get_log_mapping(optarg,
|
|
prioritynames);
|
|
if (state.syslog_priority == -1) {
|
|
errx(4, "unrecognized syslog priority");
|
|
}
|
|
state.syslog_enabled = true;
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 'S':
|
|
state.syslog_enabled = true;
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 't':
|
|
state.title = optarg;
|
|
break;
|
|
case 'T':
|
|
state.syslog_tag = optarg;
|
|
state.syslog_enabled = true;
|
|
state.supervision_enabled = true;
|
|
break;
|
|
case 'u':
|
|
state.user = optarg;
|
|
break;
|
|
case 'h':
|
|
usage(0);
|
|
__builtin_unreachable();
|
|
default:
|
|
usage(1);
|
|
}
|
|
}
|
|
argc -= optind;
|
|
argv += optind;
|
|
state.argv = argv;
|
|
|
|
if (argc == 0) {
|
|
usage(1);
|
|
}
|
|
|
|
if (!state.title) {
|
|
state.title = argv[0];
|
|
}
|
|
|
|
if (state.output_filename) {
|
|
state.output_fd = open_log(state.output_filename);
|
|
if (state.output_fd == -1) {
|
|
err(7, "open");
|
|
}
|
|
}
|
|
|
|
if (state.syslog_enabled) {
|
|
openlog(state.syslog_tag, LOG_PID | LOG_NDELAY,
|
|
state.syslog_facility);
|
|
}
|
|
|
|
/*
|
|
* Try to open the pidfile before calling daemon(3),
|
|
* to be able to report the error intelligently
|
|
*/
|
|
open_pid_files(&state);
|
|
if (daemon(state.keep_cur_workdir, state.keep_fds_open) == -1) {
|
|
warn("daemon");
|
|
daemon_terminate(&state);
|
|
}
|
|
/* Write out parent pidfile if needed. */
|
|
pidfile_write(state.parent_pidfh);
|
|
|
|
if (state.supervision_enabled) {
|
|
/* Block SIGTERM to avoid racing until the child is spawned. */
|
|
if (sigprocmask(SIG_BLOCK, &state.mask_term, &state.mask_orig)) {
|
|
warn("sigprocmask");
|
|
daemon_terminate(&state);
|
|
}
|
|
|
|
setup_signals(&state);
|
|
|
|
/*
|
|
* Try to protect against pageout kill. Ignore the
|
|
* error, madvise(2) will fail only if a process does
|
|
* not have superuser privileges.
|
|
*/
|
|
(void)madvise(NULL, 0, MADV_PROTECT);
|
|
}
|
|
do {
|
|
daemon_eventloop(&state);
|
|
close(state.pipe_fd[0]);
|
|
state.pipe_fd[0] = -1;
|
|
} while (state.restart_enabled && !terminate);
|
|
|
|
daemon_terminate(&state);
|
|
}
|
|
|
|
|
|
/*
|
|
* Main event loop: fork the child and watch for events.
|
|
* In legacy mode simply execve into the target process.
|
|
*
|
|
* Signal handling logic:
|
|
*
|
|
* - SIGTERM is masked while there is no child.
|
|
*
|
|
* - SIGCHLD is masked while reading from the pipe. SIGTERM has to be
|
|
* caught, to avoid indefinite blocking on read().
|
|
*
|
|
* - Both SIGCHLD and SIGTERM are masked before calling sigsuspend()
|
|
* to avoid racing.
|
|
*
|
|
* - After SIGTERM is recieved and propagated to the child there are
|
|
* several options on what to do next:
|
|
* - read until EOF
|
|
* - read until EOF but only for a while
|
|
* - bail immediately
|
|
* Currently the third option is used, because otherwise there is no
|
|
* guarantee that read() won't block indefinitely if the child refuses
|
|
* to depart. To handle the second option, a different approach
|
|
* would be needed (procctl()?).
|
|
*
|
|
* - Child's exit might be detected by receiveing EOF from the pipe.
|
|
* But the child might have closed its stdout and stderr, so deamon
|
|
* must wait for the SIGCHLD to ensure that the child is actually gone.
|
|
*/
|
|
static void
|
|
daemon_eventloop(struct daemon_state *state)
|
|
{
|
|
if (state->supervision_enabled) {
|
|
if (pipe(state->pipe_fd)) {
|
|
err(1, "pipe");
|
|
}
|
|
/*
|
|
* Spawn a child to exec the command.
|
|
*/
|
|
child_gone = 0;
|
|
pid = fork();
|
|
}
|
|
|
|
/* fork failed, this can only happen when supervision is enabled */
|
|
if (pid == -1) {
|
|
warn("fork");
|
|
daemon_terminate(state);
|
|
}
|
|
|
|
/* fork succeeded, this is child's branch or supervision is disabled */
|
|
if (pid == 0) {
|
|
pidfile_write(state->child_pidfh);
|
|
|
|
if (state->user != NULL) {
|
|
restrict_process(state->user);
|
|
}
|
|
/*
|
|
* In supervision mode, the child gets the original sigmask,
|
|
* and dup'd pipes.
|
|
*/
|
|
if (state->supervision_enabled) {
|
|
close(state->pipe_fd[0]);
|
|
if (sigprocmask(SIG_SETMASK, &state->mask_orig, NULL)) {
|
|
err(1, "sigprogmask");
|
|
}
|
|
if (state->stdmask & STDERR_FILENO) {
|
|
if (dup2(state->pipe_fd[1], STDERR_FILENO) == -1) {
|
|
err(1, "dup2");
|
|
}
|
|
}
|
|
if (state->stdmask & STDOUT_FILENO) {
|
|
if (dup2(state->pipe_fd[1], STDOUT_FILENO) == -1) {
|
|
err(1, "dup2");
|
|
}
|
|
}
|
|
if (state->pipe_fd[1] != STDERR_FILENO &&
|
|
state->pipe_fd[1] != STDOUT_FILENO) {
|
|
close(state->pipe_fd[1]);
|
|
}
|
|
}
|
|
execvp(state->argv[0], state->argv);
|
|
/* execvp() failed - report error and exit this process */
|
|
err(1, "%s", state->argv[0]);
|
|
}
|
|
|
|
/*
|
|
* else: pid > 0
|
|
* fork succeeded, this is the parent branch, this can only happen when
|
|
* supervision is enabled.
|
|
*
|
|
* Unblock SIGTERM - now there is a valid child PID to signal to.
|
|
*/
|
|
if (sigprocmask(SIG_UNBLOCK, &state->mask_term, NULL)) {
|
|
warn("sigprocmask");
|
|
daemon_terminate(state);
|
|
}
|
|
close(state->pipe_fd[1]);
|
|
state->pipe_fd[1] = -1;
|
|
|
|
setproctitle("%s[%d]", state->title, (int)pid);
|
|
for (;;) {
|
|
if (child_gone && state->child_eof) {
|
|
break;
|
|
}
|
|
|
|
if (terminate) {
|
|
daemon_terminate(state);
|
|
}
|
|
|
|
if (state->child_eof) {
|
|
if (sigprocmask(SIG_BLOCK, &state->mask_susp, NULL)) {
|
|
warn("sigprocmask");
|
|
daemon_terminate(state);
|
|
}
|
|
while (!terminate && !child_gone) {
|
|
sigsuspend(&state->mask_orig);
|
|
}
|
|
if (sigprocmask(SIG_UNBLOCK, &state->mask_susp, NULL)) {
|
|
warn("sigprocmask");
|
|
daemon_terminate(state);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
if (sigprocmask(SIG_BLOCK, &state->mask_read, NULL)) {
|
|
warn("sigprocmask");
|
|
daemon_terminate(state);
|
|
}
|
|
|
|
state->child_eof = !listen_child(state->pipe_fd[0], state);
|
|
|
|
if (sigprocmask(SIG_UNBLOCK, &state->mask_read, NULL)) {
|
|
warn("sigprocmask");
|
|
daemon_terminate(state);
|
|
}
|
|
|
|
}
|
|
|
|
/*
|
|
* At the end of the loop the the child is already gone.
|
|
* Block SIGTERM to avoid racing until the child is spawned.
|
|
*/
|
|
if (sigprocmask(SIG_BLOCK, &state->mask_term, NULL)) {
|
|
warn("sigprocmask");
|
|
daemon_terminate(state);
|
|
}
|
|
|
|
/* sleep before exiting mainloop if restart is enabled */
|
|
if (state->restart_enabled && !terminate) {
|
|
daemon_sleep(state->restart_delay, 0);
|
|
}
|
|
}
|
|
|
|
static void
|
|
daemon_sleep(time_t secs, long nsecs)
|
|
{
|
|
struct timespec ts = { secs, nsecs };
|
|
|
|
while (!terminate && nanosleep(&ts, &ts) == -1) {
|
|
if (errno != EINTR) {
|
|
err(1, "nanosleep");
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Setup SIGTERM, SIGCHLD and SIGHUP handlers.
|
|
* To avoid racing SIGCHLD with SIGTERM corresponding
|
|
* signal handlers mask the other signal.
|
|
*/
|
|
static void
|
|
setup_signals(struct daemon_state *state)
|
|
{
|
|
struct sigaction act_term = { 0 };
|
|
struct sigaction act_chld = { 0 };
|
|
struct sigaction act_hup = { 0 };
|
|
|
|
/* Setup SIGTERM */
|
|
act_term.sa_handler = handle_term;
|
|
sigemptyset(&act_term.sa_mask);
|
|
sigaddset(&act_term.sa_mask, SIGCHLD);
|
|
if (sigaction(SIGTERM, &act_term, NULL) == -1) {
|
|
warn("sigaction");
|
|
daemon_terminate(state);
|
|
}
|
|
|
|
/* Setup SIGCHLD */
|
|
act_chld.sa_handler = handle_chld;
|
|
sigemptyset(&act_chld.sa_mask);
|
|
sigaddset(&act_chld.sa_mask, SIGTERM);
|
|
if (sigaction(SIGCHLD, &act_chld, NULL) == -1) {
|
|
warn("sigaction");
|
|
daemon_terminate(state);
|
|
}
|
|
|
|
/* Setup SIGHUP if configured */
|
|
if (!state->log_reopen || state->output_fd < 0) {
|
|
return;
|
|
}
|
|
|
|
act_hup.sa_handler = handle_hup;
|
|
sigemptyset(&act_hup.sa_mask);
|
|
if (sigaction(SIGHUP, &act_hup, NULL) == -1) {
|
|
warn("sigaction");
|
|
daemon_terminate(state);
|
|
}
|
|
}
|
|
|
|
static void
|
|
open_pid_files(struct daemon_state *state)
|
|
{
|
|
pid_t fpid;
|
|
int serrno;
|
|
|
|
if (state->child_pidfile) {
|
|
state->child_pidfh = pidfile_open(state->child_pidfile, 0600, &fpid);
|
|
if (state->child_pidfh == NULL) {
|
|
if (errno == EEXIST) {
|
|
errx(3, "process already running, pid: %d",
|
|
fpid);
|
|
}
|
|
err(2, "pidfile ``%s''", state->child_pidfile);
|
|
}
|
|
}
|
|
/* Do the same for the actual daemon process. */
|
|
if (state->parent_pidfile) {
|
|
state->parent_pidfh= pidfile_open(state->parent_pidfile, 0600, &fpid);
|
|
if (state->parent_pidfh == NULL) {
|
|
serrno = errno;
|
|
pidfile_remove(state->child_pidfh);
|
|
errno = serrno;
|
|
if (errno == EEXIST) {
|
|
errx(3, "process already running, pid: %d",
|
|
fpid);
|
|
}
|
|
err(2, "ppidfile ``%s''", state->parent_pidfile);
|
|
}
|
|
}
|
|
}
|
|
|
|
static int
|
|
get_log_mapping(const char *str, const CODE *c)
|
|
{
|
|
const CODE *cp;
|
|
for (cp = c; cp->c_name; cp++)
|
|
if (strcmp(cp->c_name, str) == 0) {
|
|
return cp->c_val;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
static void
|
|
restrict_process(const char *user)
|
|
{
|
|
struct passwd *pw = NULL;
|
|
|
|
pw = getpwnam(user);
|
|
if (pw == NULL) {
|
|
errx(1, "unknown user: %s", user);
|
|
}
|
|
|
|
if (setusercontext(NULL, pw, pw->pw_uid, LOGIN_SETALL) != 0) {
|
|
errx(1, "failed to set user environment");
|
|
}
|
|
|
|
setenv("USER", pw->pw_name, 1);
|
|
setenv("HOME", pw->pw_dir, 1);
|
|
setenv("SHELL", *pw->pw_shell ? pw->pw_shell : _PATH_BSHELL, 1);
|
|
}
|
|
|
|
/*
|
|
* We try to collect whole lines terminated by '\n'. Otherwise we collect a
|
|
* full buffer, and then output it.
|
|
*
|
|
* Return value of false is assumed to mean EOF or error, and true indicates to
|
|
* continue reading.
|
|
*/
|
|
static bool
|
|
listen_child(int fd, struct daemon_state *state)
|
|
{
|
|
static unsigned char buf[LBUF_SIZE];
|
|
static size_t bytes_read = 0;
|
|
int rv;
|
|
|
|
assert(state != NULL);
|
|
assert(bytes_read < LBUF_SIZE - 1);
|
|
|
|
if (do_log_reopen) {
|
|
reopen_log(state);
|
|
}
|
|
rv = read(fd, buf + bytes_read, LBUF_SIZE - bytes_read - 1);
|
|
if (rv > 0) {
|
|
unsigned char *cp;
|
|
|
|
bytes_read += rv;
|
|
assert(bytes_read <= LBUF_SIZE - 1);
|
|
/* Always NUL-terminate just in case. */
|
|
buf[LBUF_SIZE - 1] = '\0';
|
|
/*
|
|
* Chomp line by line until we run out of buffer.
|
|
* This does not take NUL characters into account.
|
|
*/
|
|
while ((cp = memchr(buf, '\n', bytes_read)) != NULL) {
|
|
size_t bytes_line = cp - buf + 1;
|
|
assert(bytes_line <= bytes_read);
|
|
do_output(buf, bytes_line, state);
|
|
bytes_read -= bytes_line;
|
|
memmove(buf, cp + 1, bytes_read);
|
|
}
|
|
/* Wait until the buffer is full. */
|
|
if (bytes_read < LBUF_SIZE - 1) {
|
|
return true;
|
|
}
|
|
do_output(buf, bytes_read, state);
|
|
bytes_read = 0;
|
|
return true;
|
|
} else if (rv == -1) {
|
|
/* EINTR should trigger another read. */
|
|
if (errno == EINTR) {
|
|
return true;
|
|
} else {
|
|
warn("read");
|
|
return false;
|
|
}
|
|
}
|
|
/* Upon EOF, we have to flush what's left of the buffer. */
|
|
if (bytes_read > 0) {
|
|
do_output(buf, bytes_read, state);
|
|
bytes_read = 0;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* The default behavior is to stay silent if the user wants to redirect
|
|
* output to a file and/or syslog. If neither are provided, then we bounce
|
|
* everything back to parent's stdout.
|
|
*/
|
|
static void
|
|
do_output(const unsigned char *buf, size_t len, struct daemon_state *state)
|
|
{
|
|
assert(len <= LBUF_SIZE);
|
|
assert(state != NULL);
|
|
|
|
if (len < 1) {
|
|
return;
|
|
}
|
|
if (state->syslog_enabled) {
|
|
syslog(state->syslog_priority, "%.*s", (int)len, buf);
|
|
}
|
|
if (state->output_fd != -1) {
|
|
if (write(state->output_fd, buf, len) == -1)
|
|
warn("write");
|
|
}
|
|
if (state->keep_fds_open &&
|
|
!state->syslog_enabled &&
|
|
state->output_fd == -1) {
|
|
printf("%.*s", (int)len, buf);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We use the global PID acquired directly from fork. If there is no valid
|
|
* child pid, the handler should be blocked and/or child_gone == 1.
|
|
*/
|
|
static void
|
|
handle_term(int signo)
|
|
{
|
|
if (pid > 0 && !child_gone) {
|
|
kill(pid, signo);
|
|
}
|
|
terminate = 1;
|
|
}
|
|
|
|
static void
|
|
handle_chld(int signo __unused)
|
|
{
|
|
|
|
for (;;) {
|
|
int rv = waitpid(-1, NULL, WNOHANG);
|
|
if (pid == rv) {
|
|
child_gone = 1;
|
|
break;
|
|
} else if (rv == -1 && errno != EINTR) {
|
|
warn("waitpid");
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
handle_hup(int signo __unused)
|
|
{
|
|
|
|
do_log_reopen = 1;
|
|
}
|
|
|
|
static int
|
|
open_log(const char *outfn)
|
|
{
|
|
|
|
return open(outfn, O_CREAT | O_WRONLY | O_APPEND | O_CLOEXEC, 0600);
|
|
}
|
|
|
|
static void
|
|
reopen_log(struct daemon_state *state)
|
|
{
|
|
int outfd;
|
|
|
|
do_log_reopen = 0;
|
|
outfd = open_log(state->output_filename);
|
|
if (state->output_fd >= 0) {
|
|
close(state->output_fd);
|
|
}
|
|
state->output_fd = outfd;
|
|
}
|
|
|
|
static void
|
|
daemon_state_init(struct daemon_state *state)
|
|
{
|
|
*state = (struct daemon_state) {
|
|
.pipe_fd = { -1, -1 },
|
|
.argv = NULL,
|
|
.parent_pidfh = NULL,
|
|
.child_pidfh = NULL,
|
|
.child_pidfile = NULL,
|
|
.parent_pidfile = NULL,
|
|
.title = NULL,
|
|
.user = NULL,
|
|
.supervision_enabled = false,
|
|
.child_eof = false,
|
|
.restart_enabled = false,
|
|
.keep_cur_workdir = 1,
|
|
.restart_delay = 1,
|
|
.stdmask = STDOUT_FILENO | STDERR_FILENO,
|
|
.syslog_enabled = false,
|
|
.log_reopen = false,
|
|
.syslog_priority = LOG_NOTICE,
|
|
.syslog_tag = "daemon",
|
|
.syslog_facility = LOG_DAEMON,
|
|
.keep_fds_open = 1,
|
|
.output_fd = -1,
|
|
.output_filename = NULL,
|
|
};
|
|
|
|
sigemptyset(&state->mask_susp);
|
|
sigemptyset(&state->mask_read);
|
|
sigemptyset(&state->mask_term);
|
|
sigemptyset(&state->mask_orig);
|
|
sigaddset(&state->mask_susp, SIGTERM);
|
|
sigaddset(&state->mask_susp, SIGCHLD);
|
|
sigaddset(&state->mask_term, SIGTERM);
|
|
sigaddset(&state->mask_read, SIGCHLD);
|
|
|
|
}
|
|
|
|
static _Noreturn void
|
|
daemon_terminate(struct daemon_state *state)
|
|
{
|
|
assert(state != NULL);
|
|
close(state->output_fd);
|
|
close(state->pipe_fd[0]);
|
|
close(state->pipe_fd[1]);
|
|
if (state->syslog_enabled) {
|
|
closelog();
|
|
}
|
|
pidfile_remove(state->child_pidfh);
|
|
pidfile_remove(state->parent_pidfh);
|
|
|
|
/*
|
|
* Note that the exit value here doesn't matter in the case of a clean
|
|
* exit; daemon(3) already detached us from the caller, nothing is left
|
|
* to care about this one.
|
|
*/
|
|
exit(1);
|
|
}
|