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Diffstat (limited to 'usr.sbin/daemon/daemon.c')
| -rw-r--r-- | usr.sbin/daemon/daemon.c | 936 |
1 files changed, 936 insertions, 0 deletions
diff --git a/usr.sbin/daemon/daemon.c b/usr.sbin/daemon/daemon.c new file mode 100644 index 000000000000..efba87de19d4 --- /dev/null +++ b/usr.sbin/daemon/daemon.c @@ -0,0 +1,936 @@ +/*- + * 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/event.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> +#define SYSLOG_NAMES +#include <syslog.h> +#include <time.h> +#include <assert.h> + +/* 1 year in seconds */ +#define MAX_RESTART_DELAY 60*60*24*365 + +/* Maximum number of restarts */ +#define MAX_RESTART_COUNT 128 + +#define LBUF_SIZE 4096 + +enum daemon_mode { + MODE_DAEMON = 0, /* simply daemonize, no supervision */ + MODE_SUPERVISE, /* initial supervision state */ + MODE_TERMINATING, /* user requested termination */ + MODE_NOCHILD, /* child is terminated, final state of the event loop */ +}; + + +struct daemon_state { + unsigned char buf[LBUF_SIZE]; + size_t pos; + 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; + enum daemon_mode mode; + int pid; + int pipe_rd; + int pipe_wr; + int keep_cur_workdir; + int kqueue_fd; + int restart_delay; + int stdmask; + int syslog_priority; + int syslog_facility; + int keep_fds_open; + int output_fd; + bool restart_enabled; + bool syslog_enabled; + bool log_reopen; + int restart_count; + int restarted_count; +}; + +static void restrict_process(const char *); +static int open_log(const char *); +static void reopen_log(struct daemon_state *); +static bool listen_child(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(struct daemon_state *); +static void daemon_state_init(struct daemon_state *); +static void daemon_eventloop(struct daemon_state *); +static void daemon_terminate(struct daemon_state *); +static void daemon_exec(struct daemon_state *); +static bool daemon_is_child_dead(struct daemon_state *); +static void daemon_set_child_pipe(struct daemon_state *); +static int daemon_setup_kqueue(void); + +static int pidfile_truncate(struct pidfh *); + +static const char shortopts[] = "+cfHSp:P:ru:o:s:l:t:m:R:T:C: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-count", required_argument, NULL, 'C' }, + { "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" + " [-C restart_count]\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-count -C <N> Restart child at most N times, then exit\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[]) +{ + const char *e = NULL; + int ch = 0; + struct daemon_state state; + + daemon_state_init(&state); + + /* Signals are processed via kqueue */ + signal(SIGHUP, SIG_IGN); + signal(SIGTERM, SIG_IGN); + + /* + * 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 'C': + state.restart_count = (int)strtonum(optarg, 0, + MAX_RESTART_COUNT, &e); + if (e != NULL) { + errx(6, "invalid restart count: %s", e); + } + 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.mode = MODE_SUPERVISE; + break; + case 'm': + state.stdmask = (int)strtonum(optarg, 0, 3, &e); + if (e != NULL) { + errx(6, "unrecognized listening mask: %s", e); + } + 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.mode = MODE_SUPERVISE; + break; + case 'p': + state.child_pidfile = optarg; + state.mode = MODE_SUPERVISE; + break; + case 'P': + state.parent_pidfile = optarg; + state.mode = MODE_SUPERVISE; + break; + case 'r': + state.restart_enabled = true; + state.mode = MODE_SUPERVISE; + break; + case 'R': + state.restart_enabled = true; + state.restart_delay = (int)strtonum(optarg, 1, + MAX_RESTART_DELAY, &e); + if (e != NULL) { + errx(6, "invalid restart delay: %s", e); + } + state.mode = MODE_SUPERVISE; + 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.mode = MODE_SUPERVISE; + break; + case 'S': + state.syslog_enabled = true; + state.mode = MODE_SUPERVISE; + break; + case 't': + state.title = optarg; + break; + case 'T': + state.syslog_tag = optarg; + state.syslog_enabled = true; + state.mode = MODE_SUPERVISE; + break; + case 'u': + state.user = optarg; + break; + case 'h': + usage(0); + __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); + + /* + * TODO: add feature to avoid backgrounding + * i.e. --foreground, -f + */ + if (daemon(state.keep_cur_workdir, state.keep_fds_open) == -1) { + warn("daemon"); + daemon_terminate(&state); + } + + if (state.mode == MODE_DAEMON) { + daemon_exec(&state); + } + + /* Write out parent pidfile if needed. */ + pidfile_write(state.parent_pidfh); + + state.kqueue_fd = daemon_setup_kqueue(); + + do { + state.mode = MODE_SUPERVISE; + daemon_eventloop(&state); + daemon_sleep(&state); + if (state.restart_enabled && state.restart_count > -1) { + if (state.restarted_count >= state.restart_count) { + state.restart_enabled = false; + } + state.restarted_count++; + } + } while (state.restart_enabled); + + daemon_terminate(&state); +} + +static void +daemon_exec(struct daemon_state *state) +{ + pidfile_write(state->child_pidfh); + + if (state->user != NULL) { + restrict_process(state->user); + } + + /* Ignored signals remain ignored after execve, unignore them */ + signal(SIGHUP, SIG_DFL); + signal(SIGTERM, SIG_DFL); + execvp(state->argv[0], state->argv); + /* execvp() failed - report error and exit this process */ + err(1, "%s", state->argv[0]); +} + +/* Main event loop: fork the child and watch for events. + * After SIGTERM is received 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()?). + */ +static void +daemon_eventloop(struct daemon_state *state) +{ + struct kevent event; + int kq; + int ret; + int pipe_fd[2]; + + /* + * 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); + + if (pipe(pipe_fd)) { + err(1, "pipe"); + } + state->pipe_rd = pipe_fd[0]; + state->pipe_wr = pipe_fd[1]; + + kq = state->kqueue_fd; + EV_SET(&event, state->pipe_rd, EVFILT_READ, EV_ADD|EV_CLEAR, 0, 0, + NULL); + if (kevent(kq, &event, 1, NULL, 0, NULL) == -1) { + err(EXIT_FAILURE, "failed to register kevent"); + } + + memset(&event, 0, sizeof(struct kevent)); + + /* Spawn a child to exec the command. */ + state->pid = fork(); + + /* fork failed, this can only happen when supervision is enabled */ + switch (state->pid) { + case -1: + warn("fork"); + state->mode = MODE_NOCHILD; + return; + /* fork succeeded, this is child's branch */ + case 0: + close(kq); + daemon_set_child_pipe(state); + daemon_exec(state); + break; + } + + /* case: pid > 0; fork succeeded */ + close(state->pipe_wr); + state->pipe_wr = -1; + setproctitle("%s[%d]", state->title, (int)state->pid); + setbuf(stdout, NULL); + + while (state->mode != MODE_NOCHILD) { + ret = kevent(kq, NULL, 0, &event, 1, NULL); + switch (ret) { + case -1: + if (errno == EINTR) + continue; + err(EXIT_FAILURE, "kevent wait"); + case 0: + continue; + } + + if (event.flags & EV_ERROR) { + errx(EXIT_FAILURE, "Event error: %s", + strerror((int)event.data)); + } + + switch (event.filter) { + case EVFILT_SIGNAL: + + switch (event.ident) { + case SIGCHLD: + if (daemon_is_child_dead(state)) { + /* child is dead, read all until EOF */ + state->pid = -1; + state->mode = MODE_NOCHILD; + while (listen_child(state)) { + continue; + } + } + continue; + case SIGTERM: + if (state->mode != MODE_SUPERVISE) { + /* user is impatient */ + /* TODO: warn about repeated SIGTERM? */ + continue; + } + + state->mode = MODE_TERMINATING; + state->restart_enabled = false; + if (state->pid > 0) { + kill(state->pid, SIGTERM); + } + /* + * TODO set kevent timer to exit + * unconditionally after some time + */ + continue; + case SIGHUP: + if (state->log_reopen && state->output_fd >= 0) { + reopen_log(state); + } + continue; + } + break; + + case EVFILT_READ: + /* + * detecting EOF is no longer necessary + * if child closes the pipe daemon will stop getting + * EVFILT_READ events + */ + + if (event.data > 0) { + (void)listen_child(state); + } + continue; + default: + assert(0 && "Unexpected kevent filter type"); + continue; + } + } + + /* EVFILT_READ kqueue filter goes away here. */ + close(state->pipe_rd); + state->pipe_rd = -1; + + /* + * We don't have to truncate the pidfile, but it's easier to test + * daemon(8) behavior in some respects if we do. We won't bother if + * the child won't be restarted. + */ + if (state->child_pidfh != NULL && state->restart_enabled) { + pidfile_truncate(state->child_pidfh); + } +} + +/* + * Note that daemon_sleep() should not be called with anything but the signal + * events in the kqueue without further consideration. + */ +static void +daemon_sleep(struct daemon_state *state) +{ + struct kevent event = { 0 }; + int ret; + + assert(state->pipe_rd == -1); + assert(state->pipe_wr == -1); + + if (!state->restart_enabled) { + return; + } + + EV_SET(&event, 0, EVFILT_TIMER, EV_ADD|EV_ONESHOT, NOTE_SECONDS, + state->restart_delay, NULL); + if (kevent(state->kqueue_fd, &event, 1, NULL, 0, NULL) == -1) { + err(1, "failed to register timer"); + } + + for (;;) { + ret = kevent(state->kqueue_fd, NULL, 0, &event, 1, NULL); + if (ret == -1) { + if (errno != EINTR) { + err(1, "kevent"); + } + + continue; + } + + /* + * Any other events being raised are indicative of a problem + * that we need to investigate. Most likely being that + * something was not cleaned up from the eventloop. + */ + assert(event.filter == EVFILT_TIMER || + event.filter == EVFILT_SIGNAL); + + if (event.filter == EVFILT_TIMER) { + /* Break's over, back to work. */ + break; + } + + /* Process any pending signals. */ + switch (event.ident) { + case SIGTERM: + /* + * We could disarm the timer, but we'll be terminating + * promptly anyways. + */ + state->restart_enabled = false; + return; + case SIGHUP: + if (state->log_reopen && state->output_fd >= 0) { + reopen_log(state); + } + + break; + case SIGCHLD: + default: + /* Discard */ + break; + } + } + + /* SIGTERM should've returned immediately. */ + assert(state->restart_enabled); +} + +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(struct daemon_state *state) +{ + ssize_t rv; + unsigned char *cp; + + assert(state != NULL); + assert(state->pos < LBUF_SIZE - 1); + + rv = read(state->pipe_rd, state->buf + state->pos, + LBUF_SIZE - state->pos - 1); + if (rv > 0) { + state->pos += rv; + assert(state->pos <= LBUF_SIZE - 1); + /* Always NUL-terminate just in case. */ + state->buf[LBUF_SIZE - 1] = '\0'; + + /* + * Find position of the last newline in the buffer. + * The buffer is guaranteed to have one or more complete lines + * if at least one newline was found when searching in reverse. + * All complete lines are flushed. + * This does not take NUL characters into account. + */ + cp = memrchr(state->buf, '\n', state->pos); + if (cp != NULL) { + size_t bytes_line = cp - state->buf + 1; + assert(bytes_line <= state->pos); + do_output(state->buf, bytes_line, state); + state->pos -= bytes_line; + memmove(state->buf, cp + 1, state->pos); + } + /* Wait until the buffer is full. */ + if (state->pos < LBUF_SIZE - 1) { + return true; + } + do_output(state->buf, state->pos, state); + state->pos = 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 (state->pos > 0) { + do_output(state->buf, state->pos, state); + state->pos = 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); + } +} + +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; + + 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) { + .buf = {0}, + .pos = 0, + .argv = NULL, + .parent_pidfh = NULL, + .child_pidfh = NULL, + .child_pidfile = NULL, + .parent_pidfile = NULL, + .title = NULL, + .user = NULL, + .mode = MODE_DAEMON, + .restart_enabled = false, + .pid = 0, + .pipe_rd = -1, + .pipe_wr = -1, + .keep_cur_workdir = 1, + .kqueue_fd = -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, + .restart_count = -1, + .restarted_count = 0 + }; +} + +static _Noreturn void +daemon_terminate(struct daemon_state *state) +{ + assert(state != NULL); + + if (state->kqueue_fd >= 0) { + close(state->kqueue_fd); + } + if (state->output_fd >= 0) { + close(state->output_fd); + } + if (state->pipe_rd >= 0) { + close(state->pipe_rd); + } + + if (state->pipe_wr >= 0) { + close(state->pipe_wr); + } + 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); +} + +/* + * Returns true if SIGCHILD came from state->pid due to its exit. + */ +static bool +daemon_is_child_dead(struct daemon_state *state) +{ + int status; + + for (;;) { + int who = waitpid(-1, &status, WNOHANG); + if (state->pid == who && (WIFEXITED(status) || + WIFSIGNALED(status))) { + return true; + } + if (who == 0) { + return false; + } + if (who == -1 && errno != EINTR) { + warn("waitpid"); + return false; + } + } +} + +static void +daemon_set_child_pipe(struct daemon_state *state) +{ + if (state->stdmask & STDERR_FILENO) { + if (dup2(state->pipe_wr, STDERR_FILENO) == -1) { + err(1, "dup2"); + } + } + if (state->stdmask & STDOUT_FILENO) { + if (dup2(state->pipe_wr, STDOUT_FILENO) == -1) { + err(1, "dup2"); + } + } + if (state->pipe_wr != STDERR_FILENO && + state->pipe_wr != STDOUT_FILENO) { + close(state->pipe_wr); + } + + /* The child gets dup'd pipes. */ + close(state->pipe_rd); +} + +static int +daemon_setup_kqueue(void) +{ + int kq; + struct kevent event = { 0 }; + + kq = kqueuex(KQUEUE_CLOEXEC); + if (kq == -1) { + err(EXIT_FAILURE, "kqueue"); + } + + EV_SET(&event, SIGHUP, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL); + if (kevent(kq, &event, 1, NULL, 0, NULL) == -1) { + err(EXIT_FAILURE, "failed to register kevent"); + } + + EV_SET(&event, SIGTERM, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL); + if (kevent(kq, &event, 1, NULL, 0, NULL) == -1) { + err(EXIT_FAILURE, "failed to register kevent"); + } + + EV_SET(&event, SIGCHLD, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL); + if (kevent(kq, &event, 1, NULL, 0, NULL) == -1) { + err(EXIT_FAILURE, "failed to register kevent"); + } + + return (kq); +} + +static int +pidfile_truncate(struct pidfh *pfh) +{ + int pfd = pidfile_fileno(pfh); + + assert(pfd >= 0); + + if (ftruncate(pfd, 0) == -1) + return (-1); + + /* + * pidfile_write(3) will always pwrite(..., 0) today, but let's assume + * it may not always and do a best-effort reset of the position just to + * set a good example. + */ + (void)lseek(pfd, 0, SEEK_SET); + return (0); +} |