X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/887035a593c8c0a1af853657c80046e17dc5581a..1d009ae71b849a95c86c3117d1b8f063fda8aae5:/unix/pty.c diff --git a/unix/pty.c b/unix/pty.c index 98ea4f27..1c9763a0 100644 --- a/unix/pty.c +++ b/unix/pty.c @@ -1,5 +1,19 @@ +/* + * Pseudo-tty backend for pterm. + * + * Unlike the other backends, data for this one is not neatly + * encapsulated into a data structure, because it wouldn't make + * sense to do so - the utmp stuff has to be done before a backend + * is initialised, and starting a second pterm from the same + * process would therefore be infeasible because privileges would + * already have been dropped. Hence, I haven't bothered to keep the + * data dynamically allocated: instead, the backend handle is just + * a null pointer and ignored everywhere. + */ + #define _XOPEN_SOURCE #define _XOPEN_SOURCE_EXTENDED +#define _GNU_SOURCE #include #include @@ -16,9 +30,9 @@ #include #include #include +#include #include "putty.h" -#include "terminal.h" #ifndef FALSE #define FALSE 0 @@ -55,23 +69,24 @@ #endif #endif -int pty_master_fd; +static Config pty_cfg; +static int pty_master_fd; +static void *pty_frontend; static char pty_name[FILENAME_MAX]; +static int pty_signal_pipe[2]; static int pty_stamped_utmp = 0; static int pty_child_pid; static int pty_utmp_helper_pid, pty_utmp_helper_pipe; -static sig_atomic_t pty_child_dead; +static int pty_term_width, pty_term_height; +static int pty_child_dead, pty_finished; +static int pty_exit_code; #ifndef OMIT_UTMP static struct utmp utmp_entry; #endif char **pty_argv; +int use_pty_argv = TRUE; -int pty_child_is_dead(void) -{ - return pty_child_dead; -} - -static void pty_size(void); +static void pty_close(void); static void setup_utmp(char *ttyname, char *location) { @@ -155,16 +170,12 @@ static void cleanup_utmp(void) static void sigchld_handler(int signum) { - pid_t pid; - int status; - pid = waitpid(-1, &status, WNOHANG); - if (pid == pty_child_pid && (WIFEXITED(status) || WIFSIGNALED(status))) - pty_child_dead = TRUE; + write(pty_signal_pipe[1], "x", 1); } static void fatal_sig_handler(int signum) { - signal(signum, SIG_DFL); + putty_signal(signum, SIG_DFL); cleanup_utmp(); setuid(getuid()); raise(signum); @@ -244,6 +255,9 @@ void pty_pre_init(void) pid_t pid; int pipefd[2]; + /* set the child signal handler straight away; it needs to be set + * before we ever fork. */ + putty_signal(SIGCHLD, sigchld_handler); pty_master_fd = -1; if (geteuid() != getuid() || getegid() != getgid()) { @@ -279,7 +293,7 @@ void pty_pre_init(void) ret = read(pipefd[0], buffer, lenof(buffer)); if (ret <= 0) { cleanup_utmp(); - exit(0); + _exit(0); } else if (!pty_stamped_utmp) { if (dlen < lenof(display)) memcpy(display+dlen, buffer, @@ -297,47 +311,45 @@ void pty_pre_init(void) * unfortunately unprotected against SIGKILL, * but that's life. */ - signal(SIGHUP, fatal_sig_handler); - signal(SIGINT, fatal_sig_handler); - signal(SIGQUIT, fatal_sig_handler); - signal(SIGILL, fatal_sig_handler); - signal(SIGABRT, fatal_sig_handler); - signal(SIGFPE, fatal_sig_handler); - signal(SIGPIPE, fatal_sig_handler); - signal(SIGALRM, fatal_sig_handler); - signal(SIGTERM, fatal_sig_handler); - signal(SIGSEGV, fatal_sig_handler); - signal(SIGUSR1, fatal_sig_handler); - signal(SIGUSR2, fatal_sig_handler); + 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 - signal(SIGBUS, fatal_sig_handler); + putty_signal(SIGBUS, fatal_sig_handler); #endif #ifdef SIGPOLL - signal(SIGPOLL, fatal_sig_handler); + putty_signal(SIGPOLL, fatal_sig_handler); #endif #ifdef SIGPROF - signal(SIGPROF, fatal_sig_handler); + putty_signal(SIGPROF, fatal_sig_handler); #endif #ifdef SIGSYS - signal(SIGSYS, fatal_sig_handler); + putty_signal(SIGSYS, fatal_sig_handler); #endif #ifdef SIGTRAP - signal(SIGTRAP, fatal_sig_handler); + putty_signal(SIGTRAP, fatal_sig_handler); #endif #ifdef SIGVTALRM - signal(SIGVTALRM, fatal_sig_handler); + putty_signal(SIGVTALRM, fatal_sig_handler); #endif #ifdef SIGXCPU - signal(SIGXCPU, fatal_sig_handler); + putty_signal(SIGXCPU, fatal_sig_handler); #endif #ifdef SIGXFSZ - signal(SIGXFSZ, fatal_sig_handler); + putty_signal(SIGXFSZ, fatal_sig_handler); #endif #ifdef SIGIO - signal(SIGIO, fatal_sig_handler); + putty_signal(SIGIO, fatal_sig_handler); #endif - /* Also clean up utmp on normal exit. */ - atexit(cleanup_utmp); setup_utmp(pty_name, display); } } @@ -346,7 +358,6 @@ void pty_pre_init(void) close(pipefd[0]); pty_utmp_helper_pid = pid; pty_utmp_helper_pipe = pipefd[1]; - signal(SIGCHLD, sigchld_handler); } #endif @@ -365,6 +376,107 @@ void pty_pre_init(void) } } +int pty_select_result(int fd, int event) +{ + char buf[4096]; + int ret; + int finished = FALSE; + + if (fd == pty_master_fd && 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 (fd == pty_signal_pipe[0]) { + pid_t pid; + int status; + char c[1]; + + read(pty_signal_pipe[0], c, 1); /* ignore its value; it'll be `x' */ + + do { + pid = waitpid(-1, &status, WNOHANG); + if (pid == pty_child_pid && + (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; + finished = TRUE; + } + } while(pid > 0); + } + + if (finished && !pty_finished) { + uxsel_del(pty_master_fd); + pty_close(); + 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. + */ + if (pty_cfg.close_on_exit == FORCE_OFF || + (pty_cfg.close_on_exit == AUTO && pty_exit_code != 0)) { + char message[512]; + 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)); + } + } + return !finished; +} + +static void pty_uxsel_setup(void) +{ + uxsel_set(pty_master_fd, 1, pty_select_result); + uxsel_set(pty_signal_pipe[0], 1, pty_select_result); +} + /* * Called to set up the pty. * @@ -373,11 +485,19 @@ void pty_pre_init(void) * Also places the canonical host name into `realhost'. It must be * freed by the caller. */ -static char *pty_init(void *frontend, +static char *pty_init(void *frontend, void **backend_handle, Config *cfg, char *host, int port, char **realhost, int nodelay) { int slavefd; pid_t pid, pgrp; + long windowid; + + pty_frontend = frontend; + *backend_handle = NULL; /* we can't sensibly use this, sadly */ + + pty_cfg = *cfg; /* structure copy */ + pty_term_width = cfg->width; + pty_term_height = cfg->height; if (pty_master_fd < 0) pty_open_master(); @@ -389,7 +509,7 @@ static char *pty_init(void *frontend, { struct termios attrs; tcgetattr(pty_master_fd, &attrs); - attrs.c_cc[VERASE] = cfg.bksp_is_delete ? '\177' : '\010'; + attrs.c_cc[VERASE] = cfg->bksp_is_delete ? '\177' : '\010'; tcsetattr(pty_master_fd, TCSANOW, &attrs); } @@ -397,10 +517,10 @@ static char *pty_init(void *frontend, * Stamp utmp (that is, tell the utmp helper process to do so), * or not. */ - if (!cfg.stamp_utmp) + if (!cfg->stamp_utmp) close(pty_utmp_helper_pipe); /* just let the child process die */ else { - char *location = get_x_display(); + 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); @@ -413,6 +533,8 @@ static char *pty_init(void *frontend, } } + windowid = get_windowid(pty_frontend); + /* * Fork and execute the command. */ @@ -431,7 +553,7 @@ static char *pty_init(void *frontend, slavefd = open(pty_name, O_RDWR); if (slavefd < 0) { perror("slave pty: open"); - exit(1); + _exit(1); } close(pty_master_fd); @@ -450,25 +572,30 @@ static char *pty_init(void *frontend, for (i = 3; i < 1024; i++) close(i); { - char term_env_var[10 + sizeof(cfg.termtype)]; - sprintf(term_env_var, "TERM=%s", cfg.termtype); + char term_env_var[10 + sizeof(cfg->termtype)]; + sprintf(term_env_var, "TERM=%s", cfg->termtype); putenv(term_env_var); } + { + char windowid_env_var[40]; + sprintf(windowid_env_var, "WINDOWID=%ld", windowid); + putenv(windowid_env_var); + } /* * SIGINT and SIGQUIT may have been set to ignored by our * parent, particularly by things like sh -c 'pterm &' and * some window managers. Reverse this for our child process. */ - signal(SIGINT, SIG_DFL); - signal(SIGQUIT, SIG_DFL); + putty_signal(SIGINT, SIG_DFL); + putty_signal(SIGQUIT, SIG_DFL); if (pty_argv) execvp(pty_argv[0], pty_argv); else { char *shell = getenv("SHELL"); char *shellname; - if (cfg.login_shell) { + if (cfg->login_shell) { char *p = strrchr(shell, '/'); - shellname = smalloc(2+strlen(shell)); + shellname = snewn(2+strlen(shell), char); p = p ? p+1 : shell; sprintf(shellname, "-%s", p); } else @@ -480,22 +607,45 @@ static char *pty_init(void *frontend, * If we're here, exec has gone badly foom. */ perror("exec"); - exit(127); + _exit(127); } else { - close(slavefd); pty_child_pid = pid; pty_child_dead = FALSE; - signal(SIGCHLD, sigchld_handler); + pty_finished = FALSE; + } + + if (pipe(pty_signal_pipe) < 0) { + perror("pipe"); + exit(1); } + pty_uxsel_setup(); return NULL; } /* + * Stub routine (we don't have any need to reconfigure this backend). + */ +static void pty_reconfig(void *handle, Config *cfg) +{ +} + +/* + * Stub routine (never called in pterm + */ +static void pty_free(void *handle) +{ +} + + +/* * Called to send data down the pty. */ -static int pty_send(char *buf, int len) +static int pty_send(void *handle, char *buf, int len) { + if (pty_master_fd < 0) + return 0; /* ignore all writes if fd closed */ + while (len > 0) { int ret = write(pty_master_fd, buf, len); if (ret < 0) { @@ -508,10 +658,19 @@ static int pty_send(char *buf, int len) return 0; } +static void pty_close(void) +{ + if (pty_master_fd >= 0) { + close(pty_master_fd); + pty_master_fd = -1; + } + close(pty_utmp_helper_pipe); /* this causes utmp to be cleaned up */ +} + /* * Called to query the current socket sendability status. */ -static int pty_sendbuffer(void) +static int pty_sendbuffer(void *handle) { return 0; } @@ -519,14 +678,19 @@ static int pty_sendbuffer(void) /* * Called to set the size of the window */ -static void pty_size(void) +static void pty_size(void *handle, int width, int height) { struct winsize size; - size.ws_row = (unsigned short)term->rows; - size.ws_col = (unsigned short)term->cols; - size.ws_xpixel = (unsigned short) term->cols * font_dimension(0); - size.ws_ypixel = (unsigned short) term->rows * font_dimension(1); + 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; } @@ -534,40 +698,54 @@ static void pty_size(void) /* * Send special codes. */ -static void pty_special(Telnet_Special code) +static void pty_special(void *handle, Telnet_Special code) { /* Do nothing! */ return; } -static Socket pty_socket(void) +static Socket pty_socket(void *handle) { return NULL; /* shouldn't ever be needed */ } -static int pty_sendok(void) +static int pty_sendok(void *handle) { return 1; } -static void pty_unthrottle(int backlog) +static void pty_unthrottle(void *handle, int backlog) { /* do nothing */ } -static int pty_ldisc(int option) +static int pty_ldisc(void *handle, int option) { return 0; /* neither editing nor echoing */ } -static int pty_exitcode(void) +static void pty_provide_ldisc(void *handle, void *ldisc) { - /* Shouldn't ever be required */ - return 0; + /* This is a stub. */ +} + +static void pty_provide_logctx(void *handle, void *logctx) +{ + /* This is a stub. */ +} + +static int pty_exitcode(void *handle) +{ + if (!pty_finished) + return -1; /* not dead yet */ + else + return pty_exit_code; } Backend pty_backend = { pty_init, + pty_free, + pty_reconfig, pty_send, pty_sendbuffer, pty_size, @@ -576,6 +754,8 @@ Backend pty_backend = { pty_exitcode, pty_sendok, pty_ldisc, + pty_provide_ldisc, + pty_provide_logctx, pty_unthrottle, 1 };