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- /*-
- * 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 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 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);
- 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 = kqueuex(KQUEUE_CLOEXEC);
- 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");
- }
- 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");
- }
- 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:
- continue;
- }
- }
- close(kq);
- close(state->pipe_rd);
- state->pipe_rd = -1;
- }
- static void
- daemon_sleep(struct daemon_state *state)
- {
- struct timespec ts = { state->restart_delay, 0 };
- if (!state->restart_enabled) {
- return;
- }
- while (nanosleep(&ts, &ts) == -1) {
- if (errno != EINTR) {
- err(1, "nanosleep");
- }
- }
- }
- 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,
- .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->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);
- }
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