diff options
Diffstat (limited to '')
| -rw-r--r-- | server.c | 554 |
1 files changed, 554 insertions, 0 deletions
diff --git a/server.c b/server.c new file mode 100644 index 0000000..05bc50f --- /dev/null +++ b/server.c @@ -0,0 +1,554 @@ +/* $OpenBSD$ */ + +/* + * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER + * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING + * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <sys/types.h> +#include <sys/ioctl.h> +#include <sys/socket.h> +#include <sys/stat.h> +#include <sys/un.h> +#include <sys/wait.h> + +#include <errno.h> +#include <fcntl.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <termios.h> +#include <time.h> +#include <unistd.h> + +#include "tmux.h" + +/* + * Main server functions. + */ + +struct clients clients; + +struct tmuxproc *server_proc; +static int server_fd = -1; +static uint64_t server_client_flags; +static int server_exit; +static struct event server_ev_accept; +static struct event server_ev_tidy; + +struct cmd_find_state marked_pane; + +static u_int message_next; +struct message_list message_log; + +static int server_loop(void); +static void server_send_exit(void); +static void server_accept(int, short, void *); +static void server_signal(int); +static void server_child_signal(void); +static void server_child_exited(pid_t, int); +static void server_child_stopped(pid_t, int); + +/* Set marked pane. */ +void +server_set_marked(struct session *s, struct winlink *wl, struct window_pane *wp) +{ + cmd_find_clear_state(&marked_pane, 0); + marked_pane.s = s; + marked_pane.wl = wl; + marked_pane.w = wl->window; + marked_pane.wp = wp; +} + +/* Clear marked pane. */ +void +server_clear_marked(void) +{ + cmd_find_clear_state(&marked_pane, 0); +} + +/* Is this the marked pane? */ +int +server_is_marked(struct session *s, struct winlink *wl, struct window_pane *wp) +{ + if (s == NULL || wl == NULL || wp == NULL) + return (0); + if (marked_pane.s != s || marked_pane.wl != wl) + return (0); + if (marked_pane.wp != wp) + return (0); + return (server_check_marked()); +} + +/* Check if the marked pane is still valid. */ +int +server_check_marked(void) +{ + return (cmd_find_valid_state(&marked_pane)); +} + +/* Create server socket. */ +int +server_create_socket(int flags, char **cause) +{ + struct sockaddr_un sa; + size_t size; + mode_t mask; + int fd, saved_errno; + + memset(&sa, 0, sizeof sa); + sa.sun_family = AF_UNIX; + size = strlcpy(sa.sun_path, socket_path, sizeof sa.sun_path); + if (size >= sizeof sa.sun_path) { + errno = ENAMETOOLONG; + goto fail; + } + unlink(sa.sun_path); + + if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) + goto fail; + + if (flags & CLIENT_DEFAULTSOCKET) + mask = umask(S_IXUSR|S_IXGRP|S_IRWXO); + else + mask = umask(S_IXUSR|S_IRWXG|S_IRWXO); + if (bind(fd, (struct sockaddr *)&sa, sizeof sa) == -1) { + saved_errno = errno; + close(fd); + errno = saved_errno; + goto fail; + } + umask(mask); + + if (listen(fd, 128) == -1) { + saved_errno = errno; + close(fd); + errno = saved_errno; + goto fail; + } + setblocking(fd, 0); + + return (fd); + +fail: + if (cause != NULL) { + xasprintf(cause, "error creating %s (%s)", socket_path, + strerror(errno)); + } + return (-1); +} + +/* Tidy up every hour. */ +static void +server_tidy_event(__unused int fd, __unused short events, __unused void *data) +{ + struct timeval tv = { .tv_sec = 3600 }; + uint64_t t = get_timer(); + + format_tidy_jobs(); + +#ifdef HAVE_MALLOC_TRIM + malloc_trim(0); +#endif + + log_debug("%s: took %llu milliseconds", __func__, + (unsigned long long)(get_timer() - t)); + evtimer_add(&server_ev_tidy, &tv); +} + +/* Fork new server. */ +int +server_start(struct tmuxproc *client, int flags, struct event_base *base, + int lockfd, char *lockfile) +{ + int fd; + sigset_t set, oldset; + struct client *c = NULL; + char *cause = NULL; + struct timeval tv = { .tv_sec = 3600 }; + + sigfillset(&set); + sigprocmask(SIG_BLOCK, &set, &oldset); + + if (~flags & CLIENT_NOFORK) { + if (proc_fork_and_daemon(&fd) != 0) { + sigprocmask(SIG_SETMASK, &oldset, NULL); + return (fd); + } + } + proc_clear_signals(client, 0); + server_client_flags = flags; + + if (event_reinit(base) != 0) + fatalx("event_reinit failed"); + server_proc = proc_start("server"); + + proc_set_signals(server_proc, server_signal); + sigprocmask(SIG_SETMASK, &oldset, NULL); + + if (log_get_level() > 1) + tty_create_log(); + if (pledge("stdio rpath wpath cpath fattr unix getpw recvfd proc exec " + "tty ps", NULL) != 0) + fatal("pledge failed"); + + input_key_build(); + RB_INIT(&windows); + RB_INIT(&all_window_panes); + TAILQ_INIT(&clients); + RB_INIT(&sessions); + key_bindings_init(); + TAILQ_INIT(&message_log); + + gettimeofday(&start_time, NULL); + +#ifdef HAVE_SYSTEMD + server_fd = systemd_create_socket(flags, &cause); +#else + server_fd = server_create_socket(flags, &cause); +#endif + if (server_fd != -1) + server_update_socket(); + if (~flags & CLIENT_NOFORK) + c = server_client_create(fd); + else + options_set_number(global_options, "exit-empty", 0); + + if (lockfd >= 0) { + unlink(lockfile); + free(lockfile); + close(lockfd); + } + + if (cause != NULL) { + if (c != NULL) { + c->exit_message = cause; + c->flags |= CLIENT_EXIT; + } else { + fprintf(stderr, "%s\n", cause); + exit(1); + } + } + + evtimer_set(&server_ev_tidy, server_tidy_event, NULL); + evtimer_add(&server_ev_tidy, &tv); + + server_acl_init(); + + server_add_accept(0); + proc_loop(server_proc, server_loop); + + job_kill_all(); + status_prompt_save_history(); + + exit(0); +} + +/* Server loop callback. */ +static int +server_loop(void) +{ + struct client *c; + u_int items; + + do { + items = cmdq_next(NULL); + TAILQ_FOREACH(c, &clients, entry) { + if (c->flags & CLIENT_IDENTIFIED) + items += cmdq_next(c); + } + } while (items != 0); + + server_client_loop(); + + if (!options_get_number(global_options, "exit-empty") && !server_exit) + return (0); + + if (!options_get_number(global_options, "exit-unattached")) { + if (!RB_EMPTY(&sessions)) + return (0); + } + + TAILQ_FOREACH(c, &clients, entry) { + if (c->session != NULL) + return (0); + } + + /* + * No attached clients therefore want to exit - flush any waiting + * clients but don't actually exit until they've gone. + */ + cmd_wait_for_flush(); + if (!TAILQ_EMPTY(&clients)) + return (0); + + if (job_still_running()) + return (0); + + return (1); +} + +/* Exit the server by killing all clients and windows. */ +static void +server_send_exit(void) +{ + struct client *c, *c1; + struct session *s, *s1; + + cmd_wait_for_flush(); + + TAILQ_FOREACH_SAFE(c, &clients, entry, c1) { + if (c->flags & CLIENT_SUSPENDED) + server_client_lost(c); + else { + c->flags |= CLIENT_EXIT; + c->exit_type = CLIENT_EXIT_SHUTDOWN; + } + c->session = NULL; + } + + RB_FOREACH_SAFE(s, sessions, &sessions, s1) + session_destroy(s, 1, __func__); +} + +/* Update socket execute permissions based on whether sessions are attached. */ +void +server_update_socket(void) +{ + struct session *s; + static int last = -1; + int n, mode; + struct stat sb; + + n = 0; + RB_FOREACH(s, sessions, &sessions) { + if (s->attached != 0) { + n++; + break; + } + } + + if (n != last) { + last = n; + + if (stat(socket_path, &sb) != 0) + return; + mode = sb.st_mode & ACCESSPERMS; + if (n != 0) { + if (mode & S_IRUSR) + mode |= S_IXUSR; + if (mode & S_IRGRP) + mode |= S_IXGRP; + if (mode & S_IROTH) + mode |= S_IXOTH; + } else + mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH); + chmod(socket_path, mode); + } +} + +/* Callback for server socket. */ +static void +server_accept(int fd, short events, __unused void *data) +{ + struct sockaddr_storage sa; + socklen_t slen = sizeof sa; + int newfd; + struct client *c; + + server_add_accept(0); + if (!(events & EV_READ)) + return; + + newfd = accept(fd, (struct sockaddr *) &sa, &slen); + if (newfd == -1) { + if (errno == EAGAIN || errno == EINTR || errno == ECONNABORTED) + return; + if (errno == ENFILE || errno == EMFILE) { + /* Delete and don't try again for 1 second. */ + server_add_accept(1); + return; + } + fatal("accept failed"); + } + + if (server_exit) { + close(newfd); + return; + } + c = server_client_create(newfd); + if (!server_acl_join(c)) { + c->exit_message = xstrdup("access not allowed"); + c->flags |= CLIENT_EXIT; + } +} + +/* + * Add accept event. If timeout is nonzero, add as a timeout instead of a read + * event - used to backoff when running out of file descriptors. + */ +void +server_add_accept(int timeout) +{ + struct timeval tv = { timeout, 0 }; + + if (server_fd == -1) + return; + + if (event_initialized(&server_ev_accept)) + event_del(&server_ev_accept); + + if (timeout == 0) { + event_set(&server_ev_accept, server_fd, EV_READ, server_accept, + NULL); + event_add(&server_ev_accept, NULL); + } else { + event_set(&server_ev_accept, server_fd, EV_TIMEOUT, + server_accept, NULL); + event_add(&server_ev_accept, &tv); + } +} + +/* Signal handler. */ +static void +server_signal(int sig) +{ + int fd; + + log_debug("%s: %s", __func__, strsignal(sig)); + switch (sig) { + case SIGINT: + case SIGTERM: + server_exit = 1; + server_send_exit(); + break; + case SIGCHLD: + server_child_signal(); + break; + case SIGUSR1: + event_del(&server_ev_accept); + fd = server_create_socket(server_client_flags, NULL); + if (fd != -1) { + close(server_fd); + server_fd = fd; + server_update_socket(); + } + server_add_accept(0); + break; + case SIGUSR2: + proc_toggle_log(server_proc); + break; + } +} + +/* Handle SIGCHLD. */ +static void +server_child_signal(void) +{ + int status; + pid_t pid; + + for (;;) { + switch (pid = waitpid(WAIT_ANY, &status, WNOHANG|WUNTRACED)) { + case -1: + if (errno == ECHILD) + return; + fatal("waitpid failed"); + case 0: + return; + } + if (WIFSTOPPED(status)) + server_child_stopped(pid, status); + else if (WIFEXITED(status) || WIFSIGNALED(status)) + server_child_exited(pid, status); + } +} + +/* Handle exited children. */ +static void +server_child_exited(pid_t pid, int status) +{ + struct window *w, *w1; + struct window_pane *wp; + + RB_FOREACH_SAFE(w, windows, &windows, w1) { + TAILQ_FOREACH(wp, &w->panes, entry) { + if (wp->pid == pid) { + wp->status = status; + wp->flags |= PANE_STATUSREADY; + + log_debug("%%%u exited", wp->id); + wp->flags |= PANE_EXITED; + + if (window_pane_destroy_ready(wp)) + server_destroy_pane(wp, 1); + break; + } + } + } + job_check_died(pid, status); +} + +/* Handle stopped children. */ +static void +server_child_stopped(pid_t pid, int status) +{ + struct window *w; + struct window_pane *wp; + + if (WSTOPSIG(status) == SIGTTIN || WSTOPSIG(status) == SIGTTOU) + return; + + RB_FOREACH(w, windows, &windows) { + TAILQ_FOREACH(wp, &w->panes, entry) { + if (wp->pid == pid) { + if (killpg(pid, SIGCONT) != 0) + kill(pid, SIGCONT); + } + } + } + job_check_died(pid, status); +} + +/* Add to message log. */ +void +server_add_message(const char *fmt, ...) +{ + struct message_entry *msg, *msg1; + char *s; + va_list ap; + u_int limit; + + va_start(ap, fmt); + xvasprintf(&s, fmt, ap); + va_end(ap); + + log_debug("message: %s", s); + + msg = xcalloc(1, sizeof *msg); + gettimeofday(&msg->msg_time, NULL); + msg->msg_num = message_next++; + msg->msg = s; + TAILQ_INSERT_TAIL(&message_log, msg, entry); + + limit = options_get_number(global_options, "message-limit"); + TAILQ_FOREACH_SAFE(msg, &message_log, entry, msg1) { + if (msg->msg_num + limit >= message_next) + break; + free(msg->msg); + TAILQ_REMOVE(&message_log, msg, entry); + free(msg); + } +} |