2 * Pseudo-tty backend for pterm.
19 #include <sys/types.h>
22 #include <sys/ioctl.h>
39 /* updwtmpx() needs the name of the wtmp file. Try to find it. */
42 #define WTMPX_FILE _PATH_WTMPX
44 #define WTMPX_FILE "/var/log/wtmpx"
50 #define LASTLOG_FILE _PATH_LASTLOG
52 #define LASTLOG_FILE "/var/log/lastlog"
57 * Set up a default for vaguely sane systems. The idea is that if
58 * OMIT_UTMP is not defined, then at least one of the symbols which
59 * enable particular forms of utmp processing should be, if only so
60 * that a link error can warn you that you should have defined
61 * OMIT_UTMP if you didn't want any. Currently HAVE_PUTUTLINE is
62 * the only such symbol.
65 #if !defined HAVE_PUTUTLINE
66 #define HAVE_PUTUTLINE
70 typedef struct pty_tag *Pty;
73 * The pty_signal_pipe, along with the SIGCHLD handler, must be
74 * process-global rather than session-specific.
76 static int pty_signal_pipe[2] = { -1, -1 }; /* obviously bogus initial val */
80 int master_fd, slave_fd;
82 char name[FILENAME_MAX];
84 int term_width, term_height;
85 int child_dead, finished;
91 * We store our pty backends in a tree sorted by master fd, so that
92 * when we get an uxsel notification we know which backend instance
93 * is the owner of the pty that caused it.
95 static int pty_compare_by_fd(void *av, void *bv)
100 if (a->master_fd < b->master_fd)
102 else if (a->master_fd > b->master_fd)
107 static int pty_find_by_fd(void *av, void *bv)
112 if (a < b->master_fd)
114 else if (a > b->master_fd)
119 static tree234 *ptys_by_fd = NULL;
122 * We also have a tree sorted by child pid, so that when we wait()
123 * in response to the signal we know which backend instance is the
124 * owner of the process that caused the signal.
126 static int pty_compare_by_pid(void *av, void *bv)
131 if (a->child_pid < b->child_pid)
133 else if (a->child_pid > b->child_pid)
138 static int pty_find_by_pid(void *av, void *bv)
140 pid_t a = *(pid_t *)av;
143 if (a < b->child_pid)
145 else if (a > b->child_pid)
150 static tree234 *ptys_by_pid = NULL;
153 * If we are using pty_pre_init(), it will need to have already
154 * allocated a pty structure, which we must then return from
155 * pty_init() rather than allocating a new one. Here we store that
156 * structure between allocation and use.
158 * Note that although most of this module is entirely capable of
159 * handling multiple ptys in a single process, pty_pre_init() is
160 * fundamentally _dependent_ on there being at most one pty per
161 * process, so the normal static-data constraints don't apply.
163 * Likewise, since utmp is only used via pty_pre_init, it too must
164 * be single-instance, so we can declare utmp-related variables
167 static Pty single_pty = NULL;
170 static pid_t pty_utmp_helper_pid = -1;
171 static int pty_utmp_helper_pipe = -1;
172 static int pty_stamped_utmp;
173 static struct utmpx utmp_entry;
177 * pty_argv is a grievous hack to allow a proper argv to be passed
178 * through from the Unix command line. Again, it doesn't really
179 * make sense outside a one-pty-per-process setup.
183 static void pty_close(Pty pty);
184 static void pty_try_write(Pty pty);
187 static void setup_utmp(char *ttyname, char *location)
190 struct lastlog lastlog_entry;
196 pw = getpwuid(getuid());
197 memset(&utmp_entry, 0, sizeof(utmp_entry));
198 utmp_entry.ut_type = USER_PROCESS;
199 utmp_entry.ut_pid = getpid();
200 strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line));
201 strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id));
202 strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user));
203 strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host));
205 * Apparently there are some architectures where (struct
206 * utmpx).ut_tv is not essentially struct timeval (e.g. Linux
207 * amd64). Hence the temporary.
209 gettimeofday(&tv, NULL);
210 utmp_entry.ut_tv.tv_sec = tv.tv_sec;
211 utmp_entry.ut_tv.tv_usec = tv.tv_usec;
214 pututxline(&utmp_entry);
217 updwtmpx(WTMPX_FILE, &utmp_entry);
220 memset(&lastlog_entry, 0, sizeof(lastlog_entry));
221 strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line));
222 strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host));
223 time(&lastlog_entry.ll_time);
224 if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) {
225 fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET);
226 fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog);
231 pty_stamped_utmp = 1;
235 static void cleanup_utmp(void)
239 if (!pty_stamped_utmp)
242 utmp_entry.ut_type = DEAD_PROCESS;
243 memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user));
244 gettimeofday(&tv, NULL);
245 utmp_entry.ut_tv.tv_sec = tv.tv_sec;
246 utmp_entry.ut_tv.tv_usec = tv.tv_usec;
248 updwtmpx(WTMPX_FILE, &utmp_entry);
250 memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line));
251 utmp_entry.ut_tv.tv_sec = 0;
252 utmp_entry.ut_tv.tv_usec = 0;
255 pututxline(&utmp_entry);
258 pty_stamped_utmp = 0; /* ensure we never double-cleanup */
262 static void sigchld_handler(int signum)
264 if (write(pty_signal_pipe[1], "x", 1) <= 0)
265 /* not much we can do about it */;
269 static void fatal_sig_handler(int signum)
271 putty_signal(signum, SIG_DFL);
278 static int pty_open_slave(Pty pty)
280 if (pty->slave_fd < 0) {
281 pty->slave_fd = open(pty->name, O_RDWR);
282 cloexec(pty->slave_fd);
285 return pty->slave_fd;
288 static void pty_open_master(Pty pty)
291 const char chars1[] = "pqrstuvwxyz";
292 const char chars2[] = "0123456789abcdef";
294 char master_name[20];
297 for (p1 = chars1; *p1; p1++)
298 for (p2 = chars2; *p2; p2++) {
299 sprintf(master_name, "/dev/pty%c%c", *p1, *p2);
300 pty->master_fd = open(master_name, O_RDWR);
301 if (pty->master_fd >= 0) {
302 if (geteuid() == 0 ||
303 access(master_name, R_OK | W_OK) == 0) {
305 * We must also check at this point that we are
306 * able to open the slave side of the pty. We
307 * wouldn't want to allocate the wrong master,
308 * get all the way down to forking, and _then_
309 * find we're unable to open the slave.
311 strcpy(pty->name, master_name);
312 pty->name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */
314 cloexec(pty->master_fd);
316 if (pty_open_slave(pty) >= 0 &&
317 access(pty->name, R_OK | W_OK) == 0)
319 if (pty->slave_fd > 0)
320 close(pty->slave_fd);
323 close(pty->master_fd);
327 /* If we get here, we couldn't get a tty at all. */
328 fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n");
333 /* We need to chown/chmod the /dev/ttyXX device. */
334 gp = getgrnam("tty");
335 chown(pty->name, getuid(), gp ? gp->gr_gid : -1);
336 chmod(pty->name, 0600);
339 const int flags = O_RDWR
345 pty->master_fd = open("/dev/ptmx", flags);
347 if (pty->master_fd < 0) {
348 perror("/dev/ptmx: open");
352 if (grantpt(pty->master_fd) < 0) {
357 if (unlockpt(pty->master_fd) < 0) {
362 cloexec(pty->master_fd);
364 pty->name[FILENAME_MAX-1] = '\0';
365 strncpy(pty->name, ptsname(pty->master_fd), FILENAME_MAX-1);
370 * Set the pty master into non-blocking mode.
373 fl = fcntl(pty->master_fd, F_GETFL);
374 if (fl != -1 && !(fl & O_NONBLOCK))
375 fcntl(pty->master_fd, F_SETFL, fl | O_NONBLOCK);
379 ptys_by_fd = newtree234(pty_compare_by_fd);
380 add234(ptys_by_fd, pty);
384 * Pre-initialisation. This is here to get around the fact that GTK
385 * doesn't like being run in setuid/setgid programs (probably
386 * sensibly). So before we initialise GTK - and therefore before we
387 * even process the command line - we check to see if we're running
388 * set[ug]id. If so, we open our pty master _now_, chown it as
389 * necessary, and drop privileges. We can always close it again
390 * later. If we're potentially going to be doing utmp as well, we
391 * also fork off a utmp helper process and communicate with it by
392 * means of a pipe; the utmp helper will keep privileges in order
393 * to clean up utmp when we exit (i.e. when its end of our pipe
396 void pty_pre_init(void)
405 pty = single_pty = snew(struct pty_tag);
406 bufchain_init(&pty->output_data);
408 /* set the child signal handler straight away; it needs to be set
409 * before we ever fork. */
410 putty_signal(SIGCHLD, sigchld_handler);
411 pty->master_fd = pty->slave_fd = -1;
413 pty_stamped_utmp = FALSE;
416 if (geteuid() != getuid() || getegid() != getgid()) {
417 pty_open_master(pty);
421 * Fork off the utmp helper.
423 if (pipe(pipefd) < 0) {
424 perror("pterm: pipe");
431 perror("pterm: fork");
433 } else if (pid == 0) {
434 char display[128], buffer[128];
439 * Now sit here until we receive a display name from the
440 * other end of the pipe, and then stamp utmp. Unstamp utmp
441 * again, and exit, when the pipe closes.
447 ret = read(pipefd[0], buffer, lenof(buffer));
451 } else if (!pty_stamped_utmp) {
452 if (dlen < lenof(display))
453 memcpy(display+dlen, buffer,
454 min(ret, lenof(display)-dlen));
455 if (buffer[ret-1] == '\0') {
457 * Now we have a display name. NUL-terminate
458 * it, and stamp utmp.
460 display[lenof(display)-1] = '\0';
462 * Trap as many fatal signals as we can in the
463 * hope of having the best possible chance to
464 * clean up utmp before termination. We are
465 * unfortunately unprotected against SIGKILL,
468 putty_signal(SIGHUP, fatal_sig_handler);
469 putty_signal(SIGINT, fatal_sig_handler);
470 putty_signal(SIGQUIT, fatal_sig_handler);
471 putty_signal(SIGILL, fatal_sig_handler);
472 putty_signal(SIGABRT, fatal_sig_handler);
473 putty_signal(SIGFPE, fatal_sig_handler);
474 putty_signal(SIGPIPE, fatal_sig_handler);
475 putty_signal(SIGALRM, fatal_sig_handler);
476 putty_signal(SIGTERM, fatal_sig_handler);
477 putty_signal(SIGSEGV, fatal_sig_handler);
478 putty_signal(SIGUSR1, fatal_sig_handler);
479 putty_signal(SIGUSR2, fatal_sig_handler);
481 putty_signal(SIGBUS, fatal_sig_handler);
484 putty_signal(SIGPOLL, fatal_sig_handler);
487 putty_signal(SIGPROF, fatal_sig_handler);
490 putty_signal(SIGSYS, fatal_sig_handler);
493 putty_signal(SIGTRAP, fatal_sig_handler);
496 putty_signal(SIGVTALRM, fatal_sig_handler);
499 putty_signal(SIGXCPU, fatal_sig_handler);
502 putty_signal(SIGXFSZ, fatal_sig_handler);
505 putty_signal(SIGIO, fatal_sig_handler);
507 setup_utmp(pty->name, display);
513 pty_utmp_helper_pid = pid;
514 pty_utmp_helper_pipe = pipefd[1];
521 #ifndef HAVE_NO_SETRESUID
522 int gid = getgid(), uid = getuid();
523 int setresgid(gid_t, gid_t, gid_t);
524 int setresuid(uid_t, uid_t, uid_t);
525 setresgid(gid, gid, gid);
526 setresuid(uid, uid, uid);
534 int pty_real_select_result(Pty pty, int event, int status)
538 int finished = FALSE;
542 * We've been called because our child process did
543 * something. `status' tells us what.
545 if ((WIFEXITED(status) || WIFSIGNALED(status))) {
547 * The primary child process died. We could keep
548 * the terminal open for remaining subprocesses to
549 * output to, but conventional wisdom seems to feel
550 * that that's the Wrong Thing for an xterm-alike,
551 * so we bail out now (though we don't necessarily
552 * _close_ the window, depending on the state of
553 * Close On Exit). This would be easy enough to
554 * change or make configurable if necessary.
556 pty->exit_code = status;
557 pty->child_dead = TRUE;
558 del234(ptys_by_pid, pty);
564 ret = read(pty->master_fd, buf, sizeof(buf));
567 * Clean termination condition is that either ret == 0, or ret
568 * < 0 and errno == EIO. Not sure why the latter, but it seems
571 if (ret == 0 || (ret < 0 && errno == EIO)) {
573 * We assume a clean exit if the pty has closed but the
574 * actual child process hasn't. The only way I can
575 * imagine this happening is if it detaches itself from
576 * the pty and goes daemonic - in which case the
577 * expected usage model would precisely _not_ be for
578 * the pterm window to hang around!
581 if (!pty->child_dead)
583 } else if (ret < 0) {
584 perror("read pty master");
586 } else if (ret > 0) {
587 from_backend(pty->frontend, 0, buf, ret);
589 } else if (event == 2) {
591 * Attempt to send data down the pty.
597 if (finished && !pty->finished) {
600 uxsel_del(pty->master_fd);
604 pty->finished = TRUE;
607 * This is a slight layering-violation sort of hack: only
608 * if we're not closing on exit (COE is set to Never, or to
609 * Only On Clean and it wasn't a clean exit) do we output a
610 * `terminated' message.
612 close_on_exit = conf_get_int(pty->conf, CONF_close_on_exit);
613 if (close_on_exit == FORCE_OFF ||
614 (close_on_exit == AUTO && pty->exit_code != 0)) {
616 if (WIFEXITED(pty->exit_code))
617 sprintf(message, "\r\n[pterm: process terminated with exit"
618 " code %d]\r\n", WEXITSTATUS(pty->exit_code));
619 else if (WIFSIGNALED(pty->exit_code))
620 #ifdef HAVE_NO_STRSIGNAL
621 sprintf(message, "\r\n[pterm: process terminated on signal"
622 " %d]\r\n", WTERMSIG(pty->exit_code));
624 sprintf(message, "\r\n[pterm: process terminated on signal"
625 " %d (%.400s)]\r\n", WTERMSIG(pty->exit_code),
626 strsignal(WTERMSIG(pty->exit_code)));
628 from_backend(pty->frontend, 0, message, strlen(message));
631 notify_remote_exit(pty->frontend);
637 int pty_select_result(int fd, int event)
642 if (fd == pty_signal_pipe[0]) {
647 if (read(pty_signal_pipe[0], c, 1) <= 0)
649 /* ignore its value; it'll be `x' */
652 pid = waitpid(-1, &status, WNOHANG);
654 pty = find234(ptys_by_pid, &pid, pty_find_by_pid);
657 ret = ret && pty_real_select_result(pty, -1, status);
660 pty = find234(ptys_by_fd, &fd, pty_find_by_fd);
663 ret = ret && pty_real_select_result(pty, event, 0);
669 static void pty_uxsel_setup(Pty pty)
673 rwx = 1; /* always want to read from pty */
674 if (bufchain_size(&pty->output_data))
675 rwx |= 2; /* might also want to write to it */
676 uxsel_set(pty->master_fd, rwx, pty_select_result);
679 * In principle this only needs calling once for all pty
680 * backend instances, but it's simplest just to call it every
681 * time; uxsel won't mind.
683 uxsel_set(pty_signal_pipe[0], 1, pty_select_result);
687 * Called to set up the pty.
689 * Returns an error message, or NULL on success.
691 * Also places the canonical host name into `realhost'. It must be
692 * freed by the caller.
694 static const char *pty_init(void *frontend, void **backend_handle, Conf *conf,
695 char *host, int port, char **realhost, int nodelay,
700 #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */
708 pty = snew(struct pty_tag);
709 pty->master_fd = pty->slave_fd = -1;
711 pty_stamped_utmp = FALSE;
715 pty->frontend = frontend;
716 *backend_handle = NULL; /* we can't sensibly use this, sadly */
718 pty->conf = conf_copy(conf);
719 pty->term_width = conf_get_int(conf, CONF_width);
720 pty->term_height = conf_get_int(conf, CONF_height);
722 if (pty->master_fd < 0)
723 pty_open_master(pty);
726 * Set the backspace character to be whichever of ^H and ^? is
727 * specified by bksp_is_delete.
730 struct termios attrs;
731 tcgetattr(pty->master_fd, &attrs);
732 attrs.c_cc[VERASE] = conf_get_int(conf, CONF_bksp_is_delete)
734 tcsetattr(pty->master_fd, TCSANOW, &attrs);
739 * Stamp utmp (that is, tell the utmp helper process to do so),
742 if (!conf_get_int(conf, CONF_stamp_utmp)) {
743 close(pty_utmp_helper_pipe); /* just let the child process die */
744 pty_utmp_helper_pipe = -1;
745 } else if (pty_utmp_helper_pipe >= 0) {
746 char *location = get_x_display(pty->frontend);
747 int len = strlen(location)+1, pos = 0; /* +1 to include NUL */
749 int ret = write(pty_utmp_helper_pipe, location+pos, len - pos);
751 perror("pterm: writing to utmp helper process");
752 close(pty_utmp_helper_pipe); /* arrgh, just give up */
753 pty_utmp_helper_pipe = -1;
761 #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */
762 windowid = get_windowid(pty->frontend);
766 * Fork and execute the command.
779 slavefd = pty_open_slave(pty);
781 perror("slave pty: open");
785 close(pty->master_fd);
786 fcntl(slavefd, F_SETFD, 0); /* don't close on exec */
793 ioctl(0, TIOCSCTTY, 1);
798 close(open(pty->name, O_WRONLY, 0));
801 char *term_env_var = dupprintf("TERM=%s",
802 conf_get_str(conf, CONF_termtype));
803 putenv(term_env_var);
804 /* We mustn't free term_env_var, as putenv links it into the
805 * environment in place.
808 #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */
810 char *windowid_env_var = dupprintf("WINDOWID=%ld", windowid);
811 putenv(windowid_env_var);
812 /* We mustn't free windowid_env_var, as putenv links it into the
813 * environment in place.
820 for (val = conf_get_str_strs(conf, CONF_environmt, NULL, &key);
822 val = conf_get_str_strs(conf, CONF_environmt, key, &key)) {
823 char *varval = dupcat(key, "=", val, NULL);
826 * We must not free varval, since putenv links it
827 * into the environment _in place_. Weird, but
828 * there we go. Memory usage will be rationalised
829 * as soon as we exec anyway.
835 * SIGINT, SIGQUIT and SIGPIPE may have been set to ignored by
836 * our parent, particularly by things like sh -c 'pterm &' and
837 * some window or session managers. SIGCHLD, meanwhile, was
838 * blocked during pt_main() startup. Reverse all this for our
841 putty_signal(SIGINT, SIG_DFL);
842 putty_signal(SIGQUIT, SIG_DFL);
843 putty_signal(SIGPIPE, SIG_DFL);
844 block_signal(SIGCHLD, 0);
847 * Exec the exact argument list we were given.
849 execvp(pty_argv[0], pty_argv);
851 * If that fails, and if we had exactly one argument, pass
852 * that argument to $SHELL -c.
854 * This arranges that we can _either_ follow 'pterm -e'
855 * with a list of argv elements to be fed directly to
856 * exec, _or_ with a single argument containing a command
857 * to be parsed by a shell (but, in cases of doubt, the
858 * former is more reliable).
860 * A quick survey of other terminal emulators' -e options
861 * (as of Debian squeeze) suggests that:
863 * - xterm supports both modes, more or less like this
864 * - gnome-terminal will only accept a one-string shell command
865 * - Eterm, kterm and rxvt will only accept a list of
866 * argv elements (as did older versions of pterm).
868 * It therefore seems important to support both usage
869 * modes in order to be a drop-in replacement for either
870 * xterm or gnome-terminal, and hence for anyone's
871 * plausible uses of the Debian-style alias
872 * 'x-terminal-emulator'...
874 if (pty_argv[1] == NULL) {
875 char *shell = getenv("SHELL");
877 execl(shell, shell, "-c", pty_argv[0], (void *)NULL);
880 char *shell = getenv("SHELL");
882 if (conf_get_int(conf, CONF_login_shell)) {
883 char *p = strrchr(shell, '/');
884 shellname = snewn(2+strlen(shell), char);
886 sprintf(shellname, "-%s", p);
889 execl(getenv("SHELL"), shellname, (void *)NULL);
893 * If we're here, exec has gone badly foom.
898 pty->child_pid = pid;
899 pty->child_dead = FALSE;
900 pty->finished = FALSE;
901 if (pty->slave_fd > 0)
902 close(pty->slave_fd);
904 ptys_by_pid = newtree234(pty_compare_by_pid);
905 add234(ptys_by_pid, pty);
908 if (pty_signal_pipe[0] < 0) {
909 if (pipe(pty_signal_pipe) < 0) {
913 cloexec(pty_signal_pipe[0]);
914 cloexec(pty_signal_pipe[1]);
916 pty_uxsel_setup(pty);
918 *backend_handle = pty;
920 *realhost = dupprintf("\0");
925 static void pty_reconfig(void *handle, Conf *conf)
927 Pty pty = (Pty)handle;
929 * We don't have much need to reconfigure this backend, but
930 * unfortunately we do need to pick up the setting of Close On
931 * Exit so we know whether to give a `terminated' message.
933 conf_copy_into(pty->conf, conf);
937 * Stub routine (never called in pterm).
939 static void pty_free(void *handle)
941 Pty pty = (Pty)handle;
943 /* Either of these may fail `not found'. That's fine with us. */
944 del234(ptys_by_pid, pty);
945 del234(ptys_by_fd, pty);
950 static void pty_try_write(Pty pty)
955 assert(pty->master_fd >= 0);
957 while (bufchain_size(&pty->output_data) > 0) {
958 bufchain_prefix(&pty->output_data, &data, &len);
959 ret = write(pty->master_fd, data, len);
961 if (ret < 0 && (errno == EWOULDBLOCK)) {
963 * We've sent all we can for the moment.
968 perror("write pty master");
971 bufchain_consume(&pty->output_data, ret);
974 pty_uxsel_setup(pty);
978 * Called to send data down the pty.
980 static int pty_send(void *handle, char *buf, int len)
982 Pty pty = (Pty)handle;
984 if (pty->master_fd < 0)
985 return 0; /* ignore all writes if fd closed */
987 bufchain_add(&pty->output_data, buf, len);
990 return bufchain_size(&pty->output_data);
993 static void pty_close(Pty pty)
995 if (pty->master_fd >= 0) {
996 close(pty->master_fd);
1000 if (pty_utmp_helper_pipe >= 0) {
1001 close(pty_utmp_helper_pipe); /* this causes utmp to be cleaned up */
1002 pty_utmp_helper_pipe = -1;
1008 * Called to query the current socket sendability status.
1010 static int pty_sendbuffer(void *handle)
1012 /* Pty pty = (Pty)handle; */
1017 * Called to set the size of the window
1019 static void pty_size(void *handle, int width, int height)
1021 Pty pty = (Pty)handle;
1022 struct winsize size;
1024 pty->term_width = width;
1025 pty->term_height = height;
1027 size.ws_row = (unsigned short)pty->term_height;
1028 size.ws_col = (unsigned short)pty->term_width;
1029 size.ws_xpixel = (unsigned short) pty->term_width *
1030 font_dimension(pty->frontend, 0);
1031 size.ws_ypixel = (unsigned short) pty->term_height *
1032 font_dimension(pty->frontend, 1);
1033 ioctl(pty->master_fd, TIOCSWINSZ, (void *)&size);
1038 * Send special codes.
1040 static void pty_special(void *handle, Telnet_Special code)
1042 /* Pty pty = (Pty)handle; */
1048 * Return a list of the special codes that make sense in this
1051 static const struct telnet_special *pty_get_specials(void *handle)
1053 /* Pty pty = (Pty)handle; */
1055 * Hmm. When I get round to having this actually usable, it
1056 * might be quite nice to have the ability to deliver a few
1057 * well chosen signals to the child process - SIGINT, SIGTERM,
1063 static int pty_connected(void *handle)
1065 /* Pty pty = (Pty)handle; */
1069 static int pty_sendok(void *handle)
1071 /* Pty pty = (Pty)handle; */
1075 static void pty_unthrottle(void *handle, int backlog)
1077 /* Pty pty = (Pty)handle; */
1081 static int pty_ldisc(void *handle, int option)
1083 /* Pty pty = (Pty)handle; */
1084 return 0; /* neither editing nor echoing */
1087 static void pty_provide_ldisc(void *handle, void *ldisc)
1089 /* Pty pty = (Pty)handle; */
1090 /* This is a stub. */
1093 static void pty_provide_logctx(void *handle, void *logctx)
1095 /* Pty pty = (Pty)handle; */
1096 /* This is a stub. */
1099 static int pty_exitcode(void *handle)
1101 Pty pty = (Pty)handle;
1103 return -1; /* not dead yet */
1105 return pty->exit_code;
1108 static int pty_cfg_info(void *handle)
1110 /* Pty pty = (Pty)handle; */
1114 Backend pty_backend = {