src/shared/ptyfwd.c

	ptyfwd.c revision 4ba93280223ceb5de1bcedb196c38252f334521a
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering/***
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  This file is part of systemd.
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  Copyright 2010-2013 Lennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  systemd is free software; you can redistribute it and/or modify it
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  under the terms of the GNU Lesser General Public License as published by
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  the Free Software Foundation; either version 2.1 of the License, or
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  (at your option) any later version.
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  systemd is distributed in the hope that it will be useful, but
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  WITHOUT ANY WARRANTY; without even the implied warranty of
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  Lesser General Public License for more details.
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  You should have received a copy of the GNU Lesser General Public License
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering  along with systemd; If not, see <http://www.gnu.org/licenses/>.
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering***/
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering#include <sys/epoll.h>
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering#include <sys/signalfd.h>
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering#include <sys/ioctl.h>
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering#include <limits.h>
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering#include <termios.h>
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering#include "util.h"
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering#include "ptyfwd.h"
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poetteringint process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        char in_buffer[LINE_MAX], out_buffer[LINE_MAX];
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        size_t in_buffer_full = 0, out_buffer_full = 0;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        struct epoll_event stdin_ev, stdout_ev, master_ev, signal_ev;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        bool stdin_readable = false, stdout_writable = false, master_readable = false, master_writable = false;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        bool tried_orderly_shutdown = false;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        _cleanup_close_ int ep = -1, signal_fd = -1;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        assert(master >= 0);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        assert(mask);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        assert(kill_pid == 0 || kill_pid > 1);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        assert(signo >= 0 && signo < _NSIG);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        fd_nonblock(STDIN_FILENO, 1);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        fd_nonblock(STDOUT_FILENO, 1);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        fd_nonblock(master, 1);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        signal_fd = signalfd(-1, mask, SFD_NONBLOCK|SFD_CLOEXEC);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        if (signal_fd < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                log_error("signalfd(): %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        ep = epoll_create1(EPOLL_CLOEXEC);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        if (ep < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                log_error("Failed to create epoll: %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        /* We read from STDIN only if this is actually a TTY,
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering         * otherwise we assume non-interactivity. */
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        if (isatty(STDIN_FILENO)) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                zero(stdin_ev);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                stdin_ev.events = EPOLLIN|EPOLLET;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                stdin_ev.data.fd = STDIN_FILENO;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                if (epoll_ctl(ep, EPOLL_CTL_ADD, STDIN_FILENO, &stdin_ev) < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        log_error("Failed to register STDIN in epoll: %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        zero(stdout_ev);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        stdout_ev.events = EPOLLOUT|EPOLLET;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        stdout_ev.data.fd = STDOUT_FILENO;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        zero(master_ev);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        master_ev.events = EPOLLIN|EPOLLOUT|EPOLLET;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        master_ev.data.fd = master;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        zero(signal_ev);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        signal_ev.events = EPOLLIN;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        signal_ev.data.fd = signal_fd;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        if (epoll_ctl(ep, EPOLL_CTL_ADD, STDOUT_FILENO, &stdout_ev) < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                if (errno != EPERM) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        log_error("Failed to register stdout in epoll: %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                /* stdout without epoll support. Likely redirected to regular file. */
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                stdout_writable = true;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        if (epoll_ctl(ep, EPOLL_CTL_ADD, master, &master_ev) < 0 ||
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering            epoll_ctl(ep, EPOLL_CTL_ADD, signal_fd, &signal_ev) < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                log_error("Failed to register fds in epoll: %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        for (;;) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                struct epoll_event ev[16];
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                ssize_t k;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                int i, nfds;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                if (nfds < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        if (errno == EINTR || errno == EAGAIN)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                continue;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        log_error("epoll_wait(): %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                assert(nfds >= 1);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                for (i = 0; i < nfds; i++) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        if (ev[i].data.fd == STDIN_FILENO) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (ev[i].events & (EPOLLIN|EPOLLHUP))
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        stdin_readable = true;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        } else if (ev[i].data.fd == STDOUT_FILENO) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (ev[i].events & (EPOLLOUT|EPOLLHUP))
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        stdout_writable = true;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        } else if (ev[i].data.fd == master) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (ev[i].events & (EPOLLIN|EPOLLHUP))
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        master_readable = true;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (ev[i].events & (EPOLLOUT|EPOLLHUP))
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        master_writable = true;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        } else if (ev[i].data.fd == signal_fd) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                struct signalfd_siginfo sfsi;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                ssize_t n;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                n = read(signal_fd, &sfsi, sizeof(sfsi));
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (n != sizeof(sfsi)) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        if (n >= 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_error("Failed to read from signalfd: invalid block size");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return -EIO;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        if (errno != EINTR && errno != EAGAIN) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_error("Failed to read from signalfd: %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                } else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        if (sfsi.ssi_signo == SIGWINCH) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                struct winsize ws;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                /* The window size changed, let's forward that. */
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                        ioctl(master, TIOCSWINSZ, &ws);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        } else if (sfsi.ssi_signo == SIGTERM && kill_pid > 0 && signo > 0 && !tried_orderly_shutdown) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                if (kill(kill_pid, signo) < 0)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                        return 0;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                /* This only works for systemd... */
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                tried_orderly_shutdown = true;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        } else
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return 0;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                while ((stdin_readable && in_buffer_full <= 0) ||
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                       (master_writable && in_buffer_full > 0) ||
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                       (master_readable && out_buffer_full <= 0) ||
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                       (stdout_writable && out_buffer_full > 0)) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        if (stdin_readable && in_buffer_full < LINE_MAX) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                k = read(STDIN_FILENO, in_buffer + in_buffer_full, LINE_MAX - in_buffer_full);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (k < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                stdin_readable = false;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_error("read(): %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                } else
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        in_buffer_full += (size_t) k;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        if (master_writable && in_buffer_full > 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                k = write(master, in_buffer, in_buffer_full);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (k < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                master_writable = false;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_error("write(): %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                } else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        assert(in_buffer_full >= (size_t) k);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        memmove(in_buffer, in_buffer + k, in_buffer_full - k);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        in_buffer_full -= k;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        if (master_readable && out_buffer_full < LINE_MAX) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (k < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                master_readable = false;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_error("read(): %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                }  else
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        out_buffer_full += (size_t) k;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        if (stdout_writable && out_buffer_full > 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                k = write(STDOUT_FILENO, out_buffer, out_buffer_full);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                if (k < 0) {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                stdout_writable = false;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_error("write(): %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                } else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        assert(out_buffer_full >= (size_t) k);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        memmove(out_buffer, out_buffer + k, out_buffer_full - k);
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        out_buffer_full -= k;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering}