/*
* Pseudo-tty backend for pterm.
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <assert.h>
#include <fcntl.h>
#include <termios.h>
#include <grp.h>
#include <utmp.h>
#include <pwd.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/ioctl.h>
#include <errno.h>
#include "putty.h"
#include "tree234.h"
#ifndef OMIT_UTMP
#include <utmpx.h>
#endif
#ifndef FALSE
#define FALSE 0
#endif
#ifndef TRUE
#define TRUE 1
#endif
/* updwtmpx() needs the name of the wtmp file. Try to find it. */
#ifndef WTMPX_FILE
#ifdef _PATH_WTMPX
#define WTMPX_FILE _PATH_WTMPX
#else
#define WTMPX_FILE "/var/log/wtmpx"
#endif
#endif
#ifndef LASTLOG_FILE
#ifdef _PATH_LASTLOG
#define LASTLOG_FILE _PATH_LASTLOG
#else
#define LASTLOG_FILE "/var/log/lastlog"
#endif
#endif
/*
* Set up a default for vaguely sane systems. The idea is that if
* OMIT_UTMP is not defined, then at least one of the symbols which
* enable particular forms of utmp processing should be, if only so
* that a link error can warn you that you should have defined
* OMIT_UTMP if you didn't want any. Currently HAVE_PUTUTLINE is
* the only such symbol.
*/
#ifndef OMIT_UTMP
#if !defined HAVE_PUTUTLINE
#define HAVE_PUTUTLINE
#endif
#endif
typedef struct pty_tag *Pty;
/*
* The pty_signal_pipe, along with the SIGCHLD handler, must be
* process-global rather than session-specific.
*/
static int pty_signal_pipe[2] = { -1, -1 }; /* obviously bogus initial val */
struct pty_tag {
Conf *conf;
int master_fd, slave_fd;
void *frontend;
char name[FILENAME_MAX];
pid_t child_pid;
int term_width, term_height;
int child_dead, finished;
int exit_code;
bufchain output_data;
};
/*
* We store our pty backends in a tree sorted by master fd, so that
* when we get an uxsel notification we know which backend instance
* is the owner of the pty that caused it.
*/
static int pty_compare_by_fd(void *av, void *bv)
{
Pty a = (Pty)av;
Pty b = (Pty)bv;
if (a->master_fd < b->master_fd)
return -1;
else if (a->master_fd > b->master_fd)
return +1;
return 0;
}
static int pty_find_by_fd(void *av, void *bv)
{
int a = *(int *)av;
Pty b = (Pty)bv;
if (a < b->master_fd)
return -1;
else if (a > b->master_fd)
return +1;
return 0;
}
static tree234 *ptys_by_fd = NULL;
/*
* We also have a tree sorted by child pid, so that when we wait()
* in response to the signal we know which backend instance is the
* owner of the process that caused the signal.
*/
static int pty_compare_by_pid(void *av, void *bv)
{
Pty a = (Pty)av;
Pty b = (Pty)bv;
if (a->child_pid < b->child_pid)
return -1;
else if (a->child_pid > b->child_pid)
return +1;
return 0;
}
static int pty_find_by_pid(void *av, void *bv)
{
pid_t a = *(pid_t *)av;
Pty b = (Pty)bv;
if (a < b->child_pid)
return -1;
else if (a > b->child_pid)
return +1;
return 0;
}
static tree234 *ptys_by_pid = NULL;
/*
* If we are using pty_pre_init(), it will need to have already
* allocated a pty structure, which we must then return from
* pty_init() rather than allocating a new one. Here we store that
* structure between allocation and use.
*
* Note that although most of this module is entirely capable of
* handling multiple ptys in a single process, pty_pre_init() is
* fundamentally _dependent_ on there being at most one pty per
* process, so the normal static-data constraints don't apply.
*
* Likewise, since utmp is only used via pty_pre_init, it too must
* be single-instance, so we can declare utmp-related variables
* here.
*/
static Pty single_pty = NULL;
#ifndef OMIT_UTMP
static pid_t pty_utmp_helper_pid = -1;
static int pty_utmp_helper_pipe = -1;
static int pty_stamped_utmp;
static struct utmpx utmp_entry;
#endif
/*
* pty_argv is a grievous hack to allow a proper argv to be passed
* through from the Unix command line. Again, it doesn't really
* make sense outside a one-pty-per-process setup.
*/
char **pty_argv;
char *pty_osx_envrestore_prefix;
static void pty_close(Pty pty);
static void pty_try_write(Pty pty);
#ifndef OMIT_UTMP
static void setup_utmp(char *ttyname, char *location)
{
#ifdef HAVE_LASTLOG
struct lastlog lastlog_entry;
FILE *lastlog;
#endif
struct passwd *pw;
struct timeval tv;
pw = getpwuid(getuid());
memset(&utmp_entry, 0, sizeof(utmp_entry));
utmp_entry.ut_type = USER_PROCESS;
utmp_entry.ut_pid = getpid();
strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line));
strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id));
strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user));
strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host));
/*
* Apparently there are some architectures where (struct
* utmpx).ut_tv is not essentially struct timeval (e.g. Linux
* amd64). Hence the temporary.
*/
gettimeofday(&tv, NULL);
utmp_entry.ut_tv.tv_sec = tv.tv_sec;
utmp_entry.ut_tv.tv_usec = tv.tv_usec;
setutxent();
pututxline(&utmp_entry);
endutxent();
updwtmpx(WTMPX_FILE, &utmp_entry);
#ifdef HAVE_LASTLOG
memset(&lastlog_entry, 0, sizeof(lastlog_entry));
strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line));
strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host));
time(&lastlog_entry.ll_time);
if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) {
fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET);
fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog);
fclose(lastlog);
}
#endif
pty_stamped_utmp = 1;
}
static void cleanup_utmp(void)
{
struct timeval tv;
if (!pty_stamped_utmp)
return;
utmp_entry.ut_type = DEAD_PROCESS;
memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user));
gettimeofday(&tv, NULL);
utmp_entry.ut_tv.tv_sec = tv.tv_sec;
utmp_entry.ut_tv.tv_usec = tv.tv_usec;
updwtmpx(WTMPX_FILE, &utmp_entry);
memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line));
utmp_entry.ut_tv.tv_sec = 0;
utmp_entry.ut_tv.tv_usec = 0;
setutxent();
pututxline(&utmp_entry);
endutxent();
pty_stamped_utmp = 0; /* ensure we never double-cleanup */
}
#endif
#ifndef NO_PTY_PRE_INIT
static void sigchld_handler(int signum)
{
if (write(pty_signal_pipe[1], "x", 1) <= 0)
/* not much we can do about it */;
}
#endif
#ifndef OMIT_UTMP
static void fatal_sig_handler(int signum)
{
putty_signal(signum, SIG_DFL);
cleanup_utmp();
raise(signum);
}
#endif
static int pty_open_slave(Pty pty)
{
if (pty->slave_fd < 0) {
pty->slave_fd = open(pty->name, O_RDWR);
cloexec(pty->slave_fd);
}
return pty->slave_fd;
}
static void pty_open_master(Pty pty)
{
#ifdef BSD_PTYS
const char chars1[] = "pqrstuvwxyz";
const char chars2[] = "0123456789abcdef";
const char *p1, *p2;
char master_name[20];
struct group *gp;
for (p1 = chars1; *p1; p1++)
for (p2 = chars2; *p2; p2++) {
sprintf(master_name, "/dev/pty%c%c", *p1, *p2);
pty->master_fd = open(master_name, O_RDWR);
if (pty->master_fd >= 0) {
if (geteuid() == 0 ||
access(master_name, R_OK | W_OK) == 0) {
/*
* We must also check at this point that we are
* able to open the slave side of the pty. We
* wouldn't want to allocate the wrong master,
* get all the way down to forking, and _then_
* find we're unable to open the slave.
*/
strcpy(pty->name, master_name);
pty->name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */
cloexec(pty->master_fd);
if (pty_open_slave(pty) >= 0 &&
access(pty->name, R_OK | W_OK) == 0)
goto got_one;
if (pty->slave_fd > 0)
close(pty->slave_fd);
pty->slave_fd = -1;
}
close(pty->master_fd);
}
}
/* If we get here, we couldn't get a tty at all. */
fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n");
exit(1);
got_one:
/* We need to chown/chmod the /dev/ttyXX device. */
gp = getgrnam("tty");
chown(pty->name, getuid(), gp ? gp->gr_gid : -1);
chmod(pty->name, 0600);
#else
const int flags = O_RDWR
#ifdef O_NOCTTY
| O_NOCTTY
#endif
;
#ifdef HAVE_POSIX_OPENPT
#ifdef SET_NONBLOCK_VIA_OPENPT
/*
* OS X, as of 10.10 at least, doesn't permit me to set O_NONBLOCK
* on pty master fds via the usual fcntl mechanism. Fortunately,
* it does let me work around this by adding O_NONBLOCK to the
* posix_openpt flags parameter, which isn't a documented use of
* the API but seems to work. So we'll do that for now.
*/
pty->master_fd = posix_openpt(flags | O_NONBLOCK);
#else
pty->master_fd = posix_openpt(flags);
#endif
if (pty->master_fd < 0) {
perror("posix_openpt");
exit(1);
}
#else
pty->master_fd = open("/dev/ptmx", flags);
if (pty->master_fd < 0) {
perror("/dev/ptmx: open");
exit(1);
}
#endif
if (grantpt(pty->master_fd) < 0) {
perror("grantpt");
exit(1);
}
if (unlockpt(pty->master_fd) < 0) {
perror("unlockpt");
exit(1);
}
cloexec(pty->master_fd);
pty->name[FILENAME_MAX-1] = '\0';
strncpy(pty->name, ptsname(pty->master_fd), FILENAME_MAX-1);
#endif
#ifndef SET_NONBLOCK_VIA_OPENPT
nonblock(pty->master_fd);
#endif
if (!ptys_by_fd)
ptys_by_fd = newtree234(pty_compare_by_fd);
add234(ptys_by_fd, pty);
}
static Pty new_pty_struct(void)
{
Pty pty = snew(struct pty_tag);
pty->conf = NULL;
bufchain_init(&pty->output_data);
return pty;
}
/*
* Pre-initialisation. This is here to get around the fact that GTK
* doesn't like being run in setuid/setgid programs (probably
* sensibly). So before we initialise GTK - and therefore before we
* even process the command line - we check to see if we're running
* set[ug]id. If so, we open our pty master _now_, chown it as
* necessary, and drop privileges. We can always close it again
* later. If we're potentially going to be doing utmp as well, we
* also fork off a utmp helper process and communicate with it by
* means of a pipe; the utmp helper will keep privileges in order
* to clean up utmp when we exit (i.e. when its end of our pipe
* closes).
*/
void pty_pre_init(void)
{
#ifndef NO_PTY_PRE_INIT
Pty pty;
#ifndef OMIT_UTMP
pid_t pid;
int pipefd[2];
#endif
pty = single_pty = new_pty_struct();
/* set the child signal handler straight away; it needs to be set
* before we ever fork. */
putty_signal(SIGCHLD, sigchld_handler);
pty->master_fd = pty->slave_fd = -1;
#ifndef OMIT_UTMP
pty_stamped_utmp = FALSE;
#endif
if (geteuid() != getuid() || getegid() != getgid()) {
pty_open_master(pty);
#ifndef OMIT_UTMP
/*
* Fork off the utmp helper.
*/
if (pipe(pipefd) < 0) {
perror("pterm: pipe");
exit(1);
}
cloexec(pipefd[0]);
cloexec(pipefd[1]);
pid = fork();
if (pid < 0) {
perror("pterm: fork");
exit(1);
} else if (pid == 0) {
char display[128], buffer[128];
int dlen, ret;
close(pipefd[1]);
/*
* Now sit here until we receive a display name from the
* other end of the pipe, and then stamp utmp. Unstamp utmp
* again, and exit, when the pipe closes.
*/
dlen = 0;
while (1) {
ret = read(pipefd[0], buffer, lenof(buffer));
if (ret <= 0) {
cleanup_utmp();
_exit(0);
} else if (!pty_stamped_utmp) {
if (dlen < lenof(display))
memcpy(display+dlen, buffer,
min(ret, lenof(display)-dlen));
if (buffer[ret-1] == '\0') {
/*
* Now we have a display name. NUL-terminate
* it, and stamp utmp.
*/
display[lenof(display)-1] = '\0';
/*
* Trap as many fatal signals as we can in the
* hope of having the best possible chance to
* clean up utmp before termination. We are
* unfortunately unprotected against SIGKILL,
* but that's life.
*/
putty_signal(SIGHUP, fatal_sig_handler);
putty_signal(SIGINT, fatal_sig_handler);
putty_signal(SIGQUIT, fatal_sig_handler);
putty_signal(SIGILL, fatal_sig_handler);
putty_signal(SIGABRT, fatal_sig_handler);
putty_signal(SIGFPE, fatal_sig_handler);
putty_signal(SIGPIPE, fatal_sig_handler);
putty_signal(SIGALRM, fatal_sig_handler);
putty_signal(SIGTERM, fatal_sig_handler);
putty_signal(SIGSEGV, fatal_sig_handler);
putty_signal(SIGUSR1, fatal_sig_handler);
putty_signal(SIGUSR2, fatal_sig_handler);
#ifdef SIGBUS
putty_signal(SIGBUS, fatal_sig_handler);
#endif
#ifdef SIGPOLL
putty_signal(SIGPOLL, fatal_sig_handler);
#endif
#ifdef SIGPROF
putty_signal(SIGPROF, fatal_sig_handler);
#endif
#ifdef SIGSYS
putty_signal(SIGSYS, fatal_sig_handler);
#endif
#ifdef SIGTRAP
putty_signal(SIGTRAP, fatal_sig_handler);
#endif
#ifdef SIGVTALRM
putty_signal(SIGVTALRM, fatal_sig_handler);
#endif
#ifdef SIGXCPU
putty_signal(SIGXCPU, fatal_sig_handler);
#endif
#ifdef SIGXFSZ
putty_signal(SIGXFSZ, fatal_sig_handler);
#endif
#ifdef SIGIO
putty_signal(SIGIO, fatal_sig_handler);
#endif
setup_utmp(pty->name, display);
}
}
}
} else {
close(pipefd[0]);
pty_utmp_helper_pid = pid;
pty_utmp_helper_pipe = pipefd[1];
}
#endif
}
/* Drop privs. */
{
#ifndef HAVE_NO_SETRESUID
int gid = getgid(), uid = getuid();
int setresgid(gid_t, gid_t, gid_t);
int setresuid(uid_t, uid_t, uid_t);
if (setresgid(gid, gid, gid) < 0) {
perror("setresgid");
exit(1);
}
if (setresuid(uid, uid, uid) < 0) {
perror("setresuid");
exit(1);
}
#else
if (setgid(getgid()) < 0) {
perror("setgid");
exit(1);
}
if (setuid(getuid()) < 0) {
perror("setuid");
exit(1);
}
#endif
}
#endif /* NO_PTY_PRE_INIT */
}
int pty_real_select_result(Pty pty, int event, int status)
{
char buf[4096];
int ret;
int finished = FALSE;
if (event < 0) {
/*
* We've been called because our child process did
* something. `status' tells us what.
*/
if ((WIFEXITED(status) || WIFSIGNALED(status))) {
/*
* The primary child process died. We could keep
* the terminal open for remaining subprocesses to
* output to, but conventional wisdom seems to feel
* that that's the Wrong Thing for an xterm-alike,
* so we bail out now (though we don't necessarily
* _close_ the window, depending on the state of
* Close On Exit). This would be easy enough to
* change or make configurable if necessary.
*/
pty->exit_code = status;
pty->child_dead = TRUE;
del234(ptys_by_pid, pty);
finished = TRUE;
}
} else {
if (event == 1) {
ret = read(pty->master_fd, buf, sizeof(buf));
/*
* Clean termination condition is that either ret == 0, or ret
* < 0 and errno == EIO. Not sure why the latter, but it seems
* to happen. Boo.
*/
if (ret == 0 || (ret < 0 && errno == EIO)) {
/*
* We assume a clean exit if the pty has closed but the
* actual child process hasn't. The only way I can
* imagine this happening is if it detaches itself from
* the pty and goes daemonic - in which case the
* expected usage model would precisely _not_ be for
* the pterm window to hang around!
*/
finished = TRUE;
if (!pty->child_dead)
pty->exit_code = 0;
} else if (ret < 0) {
perror("read pty master");
exit(1);
} else if (ret > 0) {
from_backend(pty->frontend, 0, buf, ret);
}
} else if (event == 2) {
/*
* Attempt to send data down the pty.
*/
pty_try_write(pty);
}
}
if (finished && !pty->finished) {
int close_on_exit;
uxsel_del(pty->master_fd);
pty_close(pty);
pty->master_fd = -1;
pty->finished = TRUE;
/*
* This is a slight layering-violation sort of hack: only
* if we're not closing on exit (COE is set to Never, or to
* Only On Clean and it wasn't a clean exit) do we output a
* `terminated' message.
*/
close_on_exit = conf_get_int(pty->conf, CONF_close_on_exit);
if (close_on_exit == FORCE_OFF ||
(close_on_exit == AUTO && pty->exit_code != 0)) {
char message[512];
message[0] = '\0';
if (WIFEXITED(pty->exit_code))
sprintf(message, "\r\n[pterm: process terminated with exit"
" code %d]\r\n", WEXITSTATUS(pty->exit_code));
else if (WIFSIGNALED(pty->exit_code))
#ifdef HAVE_NO_STRSIGNAL
sprintf(message, "\r\n[pterm: process terminated on signal"
" %d]\r\n", WTERMSIG(pty->exit_code));
#else
sprintf(message, "\r\n[pterm: process terminated on signal"
" %d (%.400s)]\r\n", WTERMSIG(pty->exit_code),
strsignal(WTERMSIG(pty->exit_code)));
#endif
from_backend(pty->frontend, 0, message, strlen(message));
}
notify_remote_exit(pty->frontend);
}
return !finished;
}
int pty_select_result(int fd, int event)
{
int ret = TRUE;
Pty pty;
if (fd == pty_signal_pipe[0]) {
pid_t pid;
int status;
char c[1];
if (read(pty_signal_pipe[0], c, 1) <= 0)
/* ignore error */;
/* ignore its value; it'll be `x' */
do {
pid = waitpid(-1, &status, WNOHANG);
pty = find234(ptys_by_pid, &pid, pty_find_by_pid);
if (pty)
ret = ret && pty_real_select_result(pty, -1, status);
} while (pid > 0);
} else {
pty = find234(ptys_by_fd, &fd, pty_find_by_fd);
if (pty)
ret = ret && pty_real_select_result(pty, event, 0);
}
return ret;
}
static void pty_uxsel_setup(Pty pty)
{
int rwx;
rwx = 1; /* always want to read from pty */
if (bufchain_size(&pty->output_data))
rwx |= 2; /* might also want to write to it */
uxsel_set(pty->master_fd, rwx, pty_select_result);
/*
* In principle this only needs calling once for all pty
* backend instances, but it's simplest just to call it every
* time; uxsel won't mind.
*/
uxsel_set(pty_signal_pipe[0], 1, pty_select_result);
}
/*
* Called to set up the pty.
*
* Returns an error message, or NULL on success.
*
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
static const char *pty_init(void *frontend, void **backend_handle, Conf *conf,
const char *host, int port, char **realhost,
int nodelay, int keepalive)
{
int slavefd;
pid_t pid, pgrp;
#ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */
long windowid;
#endif
Pty pty;
if (single_pty) {
pty = single_pty;
assert(pty->conf == NULL);
} else {
pty = new_pty_struct();
pty->master_fd = pty->slave_fd = -1;
#ifndef OMIT_UTMP
pty_stamped_utmp = FALSE;
#endif
}
pty->frontend = frontend;
*backend_handle = NULL; /* we can't sensibly use this, sadly */
pty->conf = conf_copy(conf);
pty->term_width = conf_get_int(conf, CONF_width);
pty->term_height = conf_get_int(conf, CONF_height);
if (pty->master_fd < 0)
pty_open_master(pty);
#ifndef OMIT_UTMP
/*
* Stamp utmp (that is, tell the utmp helper process to do so),
* or not.
*/
if (pty_utmp_helper_pipe >= 0) { /* if it's < 0, we can't anyway */
if (!conf_get_int(conf, CONF_stamp_utmp)) {
close(pty_utmp_helper_pipe); /* just let the child process die */
pty_utmp_helper_pipe = -1;
} else {
const char *location = get_x_display(pty->frontend);
int len = strlen(location)+1, pos = 0; /* +1 to include NUL */
while (pos < len) {
int ret = write(pty_utmp_helper_pipe, location+pos, len - pos);
if (ret < 0) {
perror("pterm: writing to utmp helper process");
close(pty_utmp_helper_pipe); /* arrgh, just give up */
pty_utmp_helper_pipe = -1;
break;
}
pos += ret;
}
}
}
#endif
#ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */
windowid = get_windowid(pty->frontend);
#endif
/*
* Fork and execute the command.
*/
pid = fork();
if (pid < 0) {
perror("fork");
exit(1);
}
if (pid == 0) {
struct termios attrs;
/*
* We are the child.
*/
if (pty_osx_envrestore_prefix) {
int plen = strlen(pty_osx_envrestore_prefix);
extern char **environ;
char **ep;
restart_osx_env_restore:
for (ep = environ; *ep; ep++) {
char *e = *ep;
if (!strncmp(e, pty_osx_envrestore_prefix, plen)) {
int unset = (e[plen] == 'u');
char *pname = dupprintf("%.*s", (int)strcspn(e, "="), e);
char *name = pname + plen + 1;
char *value = e + strcspn(e, "=");
if (*value) value++;
value = dupstr(value);
if (unset)
unsetenv(name);
else
setenv(name, value, 1);
unsetenv(pname);
sfree(pname);
sfree(value);
goto restart_osx_env_restore;
}
}
}
slavefd = pty_open_slave(pty);
if (slavefd < 0) {
perror("slave pty: open");
_exit(1);
}
close(pty->master_fd);
noncloexec(slavefd);
dup2(slavefd, 0);
dup2(slavefd, 1);
dup2(slavefd, 2);
close(slavefd);
setsid();
#ifdef TIOCSCTTY
ioctl(0, TIOCSCTTY, 1);
#endif
pgrp = getpid();
tcsetpgrp(0, pgrp);
/*
* Set up configuration-dependent termios settings on the new
* pty. Linux would have let us do this on the pty master
* before we forked, but that fails on OS X, so we do it here
* instead.
*/
if (tcgetattr(0, &attrs) == 0) {
/*
* Set the backspace character to be whichever of ^H and
* ^? is specified by bksp_is_delete.
*/
attrs.c_cc[VERASE] = conf_get_int(conf, CONF_bksp_is_delete)
? '\177' : '\010';
/*
* Set the IUTF8 bit iff the character set is UTF-8.
*/
#ifdef IUTF8
if (frontend_is_utf8(frontend))
attrs.c_iflag |= IUTF8;
else
attrs.c_iflag &= ~IUTF8;
#endif
tcsetattr(0, TCSANOW, &attrs);
}
setpgid(pgrp, pgrp);
{
int ptyfd = open(pty->name, O_WRONLY, 0);
if (ptyfd >= 0)
close(ptyfd);
}
setpgid(pgrp, pgrp);
{
char *term_env_var = dupprintf("TERM=%s",
conf_get_str(conf, CONF_termtype));
putenv(term_env_var);
/* We mustn't free term_env_var, as putenv links it into the
* environment in place.
*/
}
#ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */
{
char *windowid_env_var = dupprintf("WINDOWID=%ld", windowid);
putenv(windowid_env_var);
/* We mustn't free windowid_env_var, as putenv links it into the
* environment in place.
*/
}
{
/*
* In case we were invoked with a --display argument that
* doesn't match DISPLAY in our actual environment, we
* should set DISPLAY for processes running inside the
* terminal to match the display the terminal itself is
* on.
*/
const char *x_display = get_x_display(pty->frontend);
char *x_display_env_var = dupprintf("DISPLAY=%s", x_display);
putenv(x_display_env_var);
/* As above, we don't free this. */
}
#endif
{
char *key, *val;
for (val = conf_get_str_strs(conf, CONF_environmt, NULL, &key);
val != NULL;
val = conf_get_str_strs(conf, CONF_environmt, key, &key)) {
char *varval = dupcat(key, "=", val, NULL);
putenv(varval);
/*
* We must not free varval, since putenv links it
* into the environment _in place_. Weird, but
* there we go. Memory usage will be rationalised
* as soon as we exec anyway.
*/
}
}
/*
* SIGINT, SIGQUIT and SIGPIPE may have been set to ignored by
* our parent, particularly by things like sh -c 'pterm &' and
* some window or session managers. SIGPIPE was also
* (potentially) blocked by us during startup. Reverse all
* this for our child process.
*/
putty_signal(SIGINT, SIG_DFL);
putty_signal(SIGQUIT, SIG_DFL);
putty_signal(SIGPIPE, SIG_DFL);
block_signal(SIGPIPE, 0);
if (pty_argv) {
/*
* Exec the exact argument list we were given.
*/
execvp(pty_argv[0], pty_argv);
/*
* If that fails, and if we had exactly one argument, pass
* that argument to $SHELL -c.
*
* This arranges that we can _either_ follow 'pterm -e'
* with a list of argv elements to be fed directly to
* exec, _or_ with a single argument containing a command
* to be parsed by a shell (but, in cases of doubt, the
* former is more reliable).
*
* A quick survey of other terminal emulators' -e options
* (as of Debian squeeze) suggests that:
*
* - xterm supports both modes, more or less like this
* - gnome-terminal will only accept a one-string shell command
* - Eterm, kterm and rxvt will only accept a list of
* argv elements (as did older versions of pterm).
*
* It therefore seems important to support both usage
* modes in order to be a drop-in replacement for either
* xterm or gnome-terminal, and hence for anyone's
* plausible uses of the Debian-style alias
* 'x-terminal-emulator'...
*/
if (pty_argv[1] == NULL) {
char *shell = getenv("SHELL");
if (shell)
execl(shell, shell, "-c", pty_argv[0], (void *)NULL);
}
} else {
char *shell = getenv("SHELL");
char *shellname;
if (conf_get_int(conf, CONF_login_shell)) {
char *p = strrchr(shell, '/');
shellname = snewn(2+strlen(shell), char);
p = p ? p+1 : shell;
sprintf(shellname, "-%s", p);
} else
shellname = shell;
execl(getenv("SHELL"), shellname, (void *)NULL);
}
/*
* If we're here, exec has gone badly foom.
*/
perror("exec");
_exit(127);
} else {
pty->child_pid = pid;
pty->child_dead = FALSE;
pty->finished = FALSE;
if (pty->slave_fd > 0)
close(pty->slave_fd);
if (!ptys_by_pid)
ptys_by_pid = newtree234(pty_compare_by_pid);
add234(ptys_by_pid, pty);
}
if (pty_signal_pipe[0] < 0) {
if (pipe(pty_signal_pipe) < 0) {
perror("pipe");
exit(1);
}
cloexec(pty_signal_pipe[0]);
cloexec(pty_signal_pipe[1]);
}
pty_uxsel_setup(pty);
*backend_handle = pty;
*realhost = dupstr("");
return NULL;
}
static void pty_reconfig(void *handle, Conf *conf)
{
Pty pty = (Pty)handle;
/*
* We don't have much need to reconfigure this backend, but
* unfortunately we do need to pick up the setting of Close On
* Exit so we know whether to give a `terminated' message.
*/
conf_copy_into(pty->conf, conf);
}
/*
* Stub routine (never called in pterm).
*/
static void pty_free(void *handle)
{
Pty pty = (Pty)handle;
/* Either of these may fail `not found'. That's fine with us. */
del234(ptys_by_pid, pty);
del234(ptys_by_fd, pty);
bufchain_clear(&pty->output_data);
conf_free(pty->conf);
pty->conf = NULL;
if (pty == single_pty) {
/*
* Leave this structure around in case we need to Restart
* Session.
*/
} else {
sfree(pty);
}
}
static void pty_try_write(Pty pty)
{
void *data;
int len, ret;
assert(pty->master_fd >= 0);
while (bufchain_size(&pty->output_data) > 0) {
bufchain_prefix(&pty->output_data, &data, &len);
ret = write(pty->master_fd, data, len);
if (ret < 0 && (errno == EWOULDBLOCK)) {
/*
* We've sent all we can for the moment.
*/
break;
}
if (ret < 0) {
perror("write pty master");
exit(1);
}
bufchain_consume(&pty->output_data, ret);
}
pty_uxsel_setup(pty);
}
/*
* Called to send data down the pty.
*/
static int pty_send(void *handle, const char *buf, int len)
{
Pty pty = (Pty)handle;
if (pty->master_fd < 0)
return 0; /* ignore all writes if fd closed */
bufchain_add(&pty->output_data, buf, len);
pty_try_write(pty);
return bufchain_size(&pty->output_data);
}
static void pty_close(Pty pty)
{
if (pty->master_fd >= 0) {
close(pty->master_fd);
pty->master_fd = -1;
}
#ifndef OMIT_UTMP
if (pty_utmp_helper_pipe >= 0) {
close(pty_utmp_helper_pipe); /* this causes utmp to be cleaned up */
pty_utmp_helper_pipe = -1;
}
#endif
}
/*
* Called to query the current socket sendability status.
*/
static int pty_sendbuffer(void *handle)
{
/* Pty pty = (Pty)handle; */
return 0;
}
/*
* Called to set the size of the window
*/
static void pty_size(void *handle, int width, int height)
{
Pty pty = (Pty)handle;
struct winsize size;
pty->term_width = width;
pty->term_height = height;
size.ws_row = (unsigned short)pty->term_height;
size.ws_col = (unsigned short)pty->term_width;
size.ws_xpixel = (unsigned short) pty->term_width *
font_dimension(pty->frontend, 0);
size.ws_ypixel = (unsigned short) pty->term_height *
font_dimension(pty->frontend, 1);
ioctl(pty->master_fd, TIOCSWINSZ, (void *)&size);
return;
}
/*
* Send special codes.
*/
static void pty_special(void *handle, Telnet_Special code)
{
/* Pty pty = (Pty)handle; */
/* Do nothing! */
return;
}
/*
* Return a list of the special codes that make sense in this
* protocol.
*/
static const struct telnet_special *pty_get_specials(void *handle)
{
/* Pty pty = (Pty)handle; */
/*
* Hmm. When I get round to having this actually usable, it
* might be quite nice to have the ability to deliver a few
* well chosen signals to the child process - SIGINT, SIGTERM,
* SIGKILL at least.
*/
return NULL;
}
static int pty_connected(void *handle)
{
/* Pty pty = (Pty)handle; */
return TRUE;
}
static int pty_sendok(void *handle)
{
/* Pty pty = (Pty)handle; */
return 1;
}
static void pty_unthrottle(void *handle, int backlog)
{
/* Pty pty = (Pty)handle; */
/* do nothing */
}
static int pty_ldisc(void *handle, int option)
{
/* Pty pty = (Pty)handle; */
return 0; /* neither editing nor echoing */
}
static void pty_provide_ldisc(void *handle, void *ldisc)
{
/* Pty pty = (Pty)handle; */
/* This is a stub. */
}
static void pty_provide_logctx(void *handle, void *logctx)
{
/* Pty pty = (Pty)handle; */
/* This is a stub. */
}
static int pty_exitcode(void *handle)
{
Pty pty = (Pty)handle;
if (!pty->finished)
return -1; /* not dead yet */
else
return pty->exit_code;
}
static int pty_cfg_info(void *handle)
{
/* Pty pty = (Pty)handle; */
return 0;
}
Backend pty_backend = {
pty_init,
pty_free,
pty_reconfig,
pty_send,
pty_sendbuffer,
pty_size,
pty_special,
pty_get_specials,
pty_connected,
pty_exitcode,
pty_sendok,
pty_ldisc,
pty_provide_ldisc,
pty_provide_logctx,
pty_unthrottle,
pty_cfg_info,
NULL /* test_for_upstream */,
"pty",
-1,
0
};