src/shared/ptyfwd.c

	ptyfwd.c revision 04d39279245834494baccfdb9349db8bf80abd13
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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering#define ESCAPE_USEC USEC_PER_SEC
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poetteringstatic bool look_for_escape(usec_t *timestamp, unsigned *counter, const char *buffer, size_t n) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        const char *p;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        assert(timestamp);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        assert(counter);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        assert(buffer);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        assert(n > 0);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        for (p = buffer; p < buffer + n; p++) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                /* Check for ^] */
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                if (*p == 0x1D) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        usec_t nw = now(CLOCK_MONOTONIC);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        if (*counter == 0 || nw > *timestamp + USEC_PER_SEC)  {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                *timestamp = nw;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                *counter = 1;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        } else {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                (*counter)++;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                if (*counter >= 3)
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        return true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                } else {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        *timestamp = 0;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        *counter = 0;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        return false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering}
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poetteringstatic int process_pty_loop(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;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        bool stdin_hangup = false, stdout_hangup = false, master_hangup = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        bool tried_orderly_shutdown = false, process_signalfd = false, quit = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        usec_t escape_timestamp = 0;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        unsigned escape_counter = 0;
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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), quit ? 0 : -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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                if (nfds == 0)
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        return 0;
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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        } else if (ev[i].data.fd == signal_fd)
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                process_signalfd = true;
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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        if (errno == EAGAIN)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                stdin_readable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        else if (errno == EIO || errno == EPIPE || errno == ECONNRESET) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                stdin_readable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                stdin_hangup = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                epoll_ctl(ep, EPOLL_CTL_DEL, STDIN_FILENO, NULL);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        } else {
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                log_error("read(): %m");
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                return -errno;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                } else {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        /* Check if ^] has been
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * pressed three times within
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * one second. If we get this
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * we quite immediately. */
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        if (look_for_escape(&escape_timestamp, &escape_counter, in_buffer + in_buffer_full, k))
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                return !quit;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                        in_buffer_full += (size_t) k;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                }
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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        if (errno == EAGAIN || errno == EIO)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                master_writable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        else if (errno == EPIPE || errno == ECONNRESET) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                master_writable = master_readable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                master_hangup = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                epoll_ctl(ep, EPOLL_CTL_DEL, master, NULL);
04d39279245834494baccfdb9349db8bf80abd13Lennart 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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        /* Note that EIO on the master
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * device might be cause by
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * vhangup() or temporary
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * closing of everything on
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * the other side, we treat it
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * like EAGAIN here and try
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * again. */
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        if (errno == EAGAIN || errno == EIO)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                master_readable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        else if (errno == EPIPE || errno == ECONNRESET) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                master_readable = master_writable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                master_hangup = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                epoll_ctl(ep, EPOLL_CTL_DEL, master, NULL);
04d39279245834494baccfdb9349db8bf80abd13Lennart 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
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        if (errno == EAGAIN)
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                                                stdout_writable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        else if (errno == EIO || errno == EPIPE || errno == ECONNRESET) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                stdout_writable = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                stdout_hangup = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                epoll_ctl(ep, EPOLL_CTL_DEL, STDOUT_FILENO, NULL);
04d39279245834494baccfdb9349db8bf80abd13Lennart 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                        }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                if (process_signalfd) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        struct signalfd_siginfo sfsi;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        ssize_t n;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        n = read(signal_fd, &sfsi, sizeof(sfsi));
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        if (n != sizeof(sfsi)) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                if (n >= 0) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        log_error("Failed to read from signalfd: invalid block size");
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        return -EIO;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                if (errno != EINTR && errno != EAGAIN) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        log_error("Failed to read from signalfd: %m");
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        return -errno;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        } else {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                if (sfsi.ssi_signo == SIGWINCH) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        struct winsize ws;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        /* The window size changed, let's forward that. */
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                ioctl(master, TIOCSWINSZ, &ws);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                } else if (sfsi.ssi_signo == SIGTERM && kill_pid > 0 && signo > 0 && !tried_orderly_shutdown) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        if (kill(kill_pid, signo) < 0)
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                quit = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        else {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                /* This only works for systemd... */
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                                tried_orderly_shutdown = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                } else
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        /* Signals that where
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * delivered via signalfd that
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * we didn't know are a reason
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                         * for us to quit */
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                        quit = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                if (stdin_hangup || stdout_hangup || master_hangup) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        /* Exit the loop if any side hung up and if
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                         * there's nothing more to write or nothing we
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                         * could write. */
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                        if ((out_buffer_full <= 0 || stdout_hangup) &&
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                            (in_buffer_full <= 0 || master_hangup))
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                                return !quit;
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering                }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering        }
4ba93280223ceb5de1bcedb196c38252f334521aLennart Poettering}
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poetteringint process_pty(int master, sigset_t *mask, pid_t kill_pid, int signo) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        struct termios saved_attr;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        bool saved = false;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        struct winsize ws;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        int r;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                ioctl(master, TIOCSWINSZ, &ws);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        if (tcgetattr(STDIN_FILENO, &saved_attr) >= 0) {
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                struct termios raw_attr;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                saved = true;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                raw_attr = saved_attr;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                cfmakeraw(&raw_attr);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                raw_attr.c_lflag &= ~ECHO;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                tcsetattr(STDIN_FILENO, TCSANOW, &raw_attr);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        }
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        r = process_pty_loop(master, mask, kill_pid, signo);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        if (saved)
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering                tcsetattr(STDIN_FILENO, TCSANOW, &saved_attr);
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering        return r;
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering
04d39279245834494baccfdb9349db8bf80abd13Lennart Poettering}