| 1 | /* |
| 2 | * Pseudo-tty backend for pterm. |
| 3 | * |
| 4 | * Unlike the other backends, data for this one is not neatly |
| 5 | * encapsulated into a data structure, because it wouldn't make |
| 6 | * sense to do so - the utmp stuff has to be done before a backend |
| 7 | * is initialised, and starting a second pterm from the same |
| 8 | * process would therefore be infeasible because privileges would |
| 9 | * already have been dropped. Hence, I haven't bothered to keep the |
| 10 | * data dynamically allocated: instead, the backend handle is just |
| 11 | * a null pointer and ignored everywhere. |
| 12 | */ |
| 13 | |
| 14 | #define _XOPEN_SOURCE |
| 15 | #define _XOPEN_SOURCE_EXTENDED |
| 16 | #include <features.h> |
| 17 | |
| 18 | #include <stdio.h> |
| 19 | #include <stdlib.h> |
| 20 | #include <string.h> |
| 21 | #include <unistd.h> |
| 22 | #include <signal.h> |
| 23 | #include <fcntl.h> |
| 24 | #include <termios.h> |
| 25 | #include <grp.h> |
| 26 | #include <utmp.h> |
| 27 | #include <pwd.h> |
| 28 | #include <time.h> |
| 29 | #include <sys/types.h> |
| 30 | #include <sys/wait.h> |
| 31 | #include <sys/ioctl.h> |
| 32 | |
| 33 | #include "putty.h" |
| 34 | |
| 35 | #ifndef FALSE |
| 36 | #define FALSE 0 |
| 37 | #endif |
| 38 | #ifndef TRUE |
| 39 | #define TRUE 1 |
| 40 | #endif |
| 41 | |
| 42 | #ifndef UTMP_FILE |
| 43 | #define UTMP_FILE "/var/run/utmp" |
| 44 | #endif |
| 45 | #ifndef WTMP_FILE |
| 46 | #define WTMP_FILE "/var/log/wtmp" |
| 47 | #endif |
| 48 | #ifndef LASTLOG_FILE |
| 49 | #ifdef _PATH_LASTLOG |
| 50 | #define LASTLOG_FILE _PATH_LASTLOG |
| 51 | #else |
| 52 | #define LASTLOG_FILE "/var/log/lastlog" |
| 53 | #endif |
| 54 | #endif |
| 55 | |
| 56 | /* |
| 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. |
| 63 | */ |
| 64 | #ifndef OMIT_UTMP |
| 65 | #if !defined HAVE_PUTUTLINE |
| 66 | #define HAVE_PUTUTLINE |
| 67 | #endif |
| 68 | #endif |
| 69 | |
| 70 | int pty_master_fd; |
| 71 | static char pty_name[FILENAME_MAX]; |
| 72 | static int pty_stamped_utmp = 0; |
| 73 | static int pty_child_pid; |
| 74 | static int pty_utmp_helper_pid, pty_utmp_helper_pipe; |
| 75 | static int pty_term_width, pty_term_height; |
| 76 | static sig_atomic_t pty_child_dead; |
| 77 | static int pty_exit_code; |
| 78 | #ifndef OMIT_UTMP |
| 79 | static struct utmp utmp_entry; |
| 80 | #endif |
| 81 | char **pty_argv; |
| 82 | |
| 83 | static void setup_utmp(char *ttyname, char *location) |
| 84 | { |
| 85 | #ifndef OMIT_UTMP |
| 86 | #ifdef HAVE_LASTLOG |
| 87 | struct lastlog lastlog_entry; |
| 88 | FILE *lastlog; |
| 89 | #endif |
| 90 | struct passwd *pw; |
| 91 | FILE *wtmp; |
| 92 | |
| 93 | pw = getpwuid(getuid()); |
| 94 | memset(&utmp_entry, 0, sizeof(utmp_entry)); |
| 95 | utmp_entry.ut_type = USER_PROCESS; |
| 96 | utmp_entry.ut_pid = getpid(); |
| 97 | strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line)); |
| 98 | strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id)); |
| 99 | strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user)); |
| 100 | strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host)); |
| 101 | time(&utmp_entry.ut_time); |
| 102 | |
| 103 | #if defined HAVE_PUTUTLINE |
| 104 | utmpname(UTMP_FILE); |
| 105 | setutent(); |
| 106 | pututline(&utmp_entry); |
| 107 | endutent(); |
| 108 | #endif |
| 109 | |
| 110 | if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) { |
| 111 | fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp); |
| 112 | fclose(wtmp); |
| 113 | } |
| 114 | |
| 115 | #ifdef HAVE_LASTLOG |
| 116 | memset(&lastlog_entry, 0, sizeof(lastlog_entry)); |
| 117 | strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line)); |
| 118 | strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host)); |
| 119 | time(&lastlog_entry.ll_time); |
| 120 | if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) { |
| 121 | fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET); |
| 122 | fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog); |
| 123 | fclose(lastlog); |
| 124 | } |
| 125 | #endif |
| 126 | |
| 127 | pty_stamped_utmp = 1; |
| 128 | |
| 129 | #endif |
| 130 | } |
| 131 | |
| 132 | static void cleanup_utmp(void) |
| 133 | { |
| 134 | #ifndef OMIT_UTMP |
| 135 | FILE *wtmp; |
| 136 | |
| 137 | if (!pty_stamped_utmp) |
| 138 | return; |
| 139 | |
| 140 | utmp_entry.ut_type = DEAD_PROCESS; |
| 141 | memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user)); |
| 142 | time(&utmp_entry.ut_time); |
| 143 | |
| 144 | if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) { |
| 145 | fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp); |
| 146 | fclose(wtmp); |
| 147 | } |
| 148 | |
| 149 | memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line)); |
| 150 | utmp_entry.ut_time = 0; |
| 151 | |
| 152 | #if defined HAVE_PUTUTLINE |
| 153 | utmpname(UTMP_FILE); |
| 154 | setutent(); |
| 155 | pututline(&utmp_entry); |
| 156 | endutent(); |
| 157 | #endif |
| 158 | |
| 159 | pty_stamped_utmp = 0; /* ensure we never double-cleanup */ |
| 160 | #endif |
| 161 | } |
| 162 | |
| 163 | static void sigchld_handler(int signum) |
| 164 | { |
| 165 | pid_t pid; |
| 166 | int status; |
| 167 | pid = waitpid(-1, &status, WNOHANG); |
| 168 | if (pid == pty_child_pid && (WIFEXITED(status) || WIFSIGNALED(status))) { |
| 169 | pty_exit_code = status; |
| 170 | pty_child_dead = TRUE; |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | static void fatal_sig_handler(int signum) |
| 175 | { |
| 176 | signal(signum, SIG_DFL); |
| 177 | cleanup_utmp(); |
| 178 | setuid(getuid()); |
| 179 | raise(signum); |
| 180 | } |
| 181 | |
| 182 | static void pty_open_master(void) |
| 183 | { |
| 184 | #ifdef BSD_PTYS |
| 185 | const char chars1[] = "pqrstuvwxyz"; |
| 186 | const char chars2[] = "0123456789abcdef"; |
| 187 | const char *p1, *p2; |
| 188 | char master_name[20]; |
| 189 | struct group *gp; |
| 190 | |
| 191 | for (p1 = chars1; *p1; p1++) |
| 192 | for (p2 = chars2; *p2; p2++) { |
| 193 | sprintf(master_name, "/dev/pty%c%c", *p1, *p2); |
| 194 | pty_master_fd = open(master_name, O_RDWR); |
| 195 | if (pty_master_fd >= 0) { |
| 196 | if (geteuid() == 0 || |
| 197 | access(master_name, R_OK | W_OK) == 0) |
| 198 | goto got_one; |
| 199 | close(pty_master_fd); |
| 200 | } |
| 201 | } |
| 202 | |
| 203 | /* If we get here, we couldn't get a tty at all. */ |
| 204 | fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n"); |
| 205 | exit(1); |
| 206 | |
| 207 | got_one: |
| 208 | strcpy(pty_name, master_name); |
| 209 | pty_name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */ |
| 210 | |
| 211 | /* We need to chown/chmod the /dev/ttyXX device. */ |
| 212 | gp = getgrnam("tty"); |
| 213 | chown(pty_name, getuid(), gp ? gp->gr_gid : -1); |
| 214 | chmod(pty_name, 0600); |
| 215 | #else |
| 216 | pty_master_fd = open("/dev/ptmx", O_RDWR); |
| 217 | |
| 218 | if (pty_master_fd < 0) { |
| 219 | perror("/dev/ptmx: open"); |
| 220 | exit(1); |
| 221 | } |
| 222 | |
| 223 | if (grantpt(pty_master_fd) < 0) { |
| 224 | perror("grantpt"); |
| 225 | exit(1); |
| 226 | } |
| 227 | |
| 228 | if (unlockpt(pty_master_fd) < 0) { |
| 229 | perror("unlockpt"); |
| 230 | exit(1); |
| 231 | } |
| 232 | |
| 233 | pty_name[FILENAME_MAX-1] = '\0'; |
| 234 | strncpy(pty_name, ptsname(pty_master_fd), FILENAME_MAX-1); |
| 235 | #endif |
| 236 | } |
| 237 | |
| 238 | /* |
| 239 | * Pre-initialisation. This is here to get around the fact that GTK |
| 240 | * doesn't like being run in setuid/setgid programs (probably |
| 241 | * sensibly). So before we initialise GTK - and therefore before we |
| 242 | * even process the command line - we check to see if we're running |
| 243 | * set[ug]id. If so, we open our pty master _now_, chown it as |
| 244 | * necessary, and drop privileges. We can always close it again |
| 245 | * later. If we're potentially going to be doing utmp as well, we |
| 246 | * also fork off a utmp helper process and communicate with it by |
| 247 | * means of a pipe; the utmp helper will keep privileges in order |
| 248 | * to clean up utmp when we exit (i.e. when its end of our pipe |
| 249 | * closes). |
| 250 | */ |
| 251 | void pty_pre_init(void) |
| 252 | { |
| 253 | pid_t pid; |
| 254 | int pipefd[2]; |
| 255 | |
| 256 | pty_master_fd = -1; |
| 257 | |
| 258 | if (geteuid() != getuid() || getegid() != getgid()) { |
| 259 | pty_open_master(); |
| 260 | } |
| 261 | |
| 262 | #ifndef OMIT_UTMP |
| 263 | /* |
| 264 | * Fork off the utmp helper. |
| 265 | */ |
| 266 | if (pipe(pipefd) < 0) { |
| 267 | perror("pterm: pipe"); |
| 268 | exit(1); |
| 269 | } |
| 270 | pid = fork(); |
| 271 | if (pid < 0) { |
| 272 | perror("pterm: fork"); |
| 273 | exit(1); |
| 274 | } else if (pid == 0) { |
| 275 | char display[128], buffer[128]; |
| 276 | int dlen, ret; |
| 277 | |
| 278 | close(pipefd[1]); |
| 279 | /* |
| 280 | * Now sit here until we receive a display name from the |
| 281 | * other end of the pipe, and then stamp utmp. Unstamp utmp |
| 282 | * again, and exit, when the pipe closes. |
| 283 | */ |
| 284 | |
| 285 | dlen = 0; |
| 286 | while (1) { |
| 287 | |
| 288 | ret = read(pipefd[0], buffer, lenof(buffer)); |
| 289 | if (ret <= 0) { |
| 290 | cleanup_utmp(); |
| 291 | exit(0); |
| 292 | } else if (!pty_stamped_utmp) { |
| 293 | if (dlen < lenof(display)) |
| 294 | memcpy(display+dlen, buffer, |
| 295 | min(ret, lenof(display)-dlen)); |
| 296 | if (buffer[ret-1] == '\0') { |
| 297 | /* |
| 298 | * Now we have a display name. NUL-terminate |
| 299 | * it, and stamp utmp. |
| 300 | */ |
| 301 | display[lenof(display)-1] = '\0'; |
| 302 | /* |
| 303 | * Trap as many fatal signals as we can in the |
| 304 | * hope of having the best possible chance to |
| 305 | * clean up utmp before termination. We are |
| 306 | * unfortunately unprotected against SIGKILL, |
| 307 | * but that's life. |
| 308 | */ |
| 309 | signal(SIGHUP, fatal_sig_handler); |
| 310 | signal(SIGINT, fatal_sig_handler); |
| 311 | signal(SIGQUIT, fatal_sig_handler); |
| 312 | signal(SIGILL, fatal_sig_handler); |
| 313 | signal(SIGABRT, fatal_sig_handler); |
| 314 | signal(SIGFPE, fatal_sig_handler); |
| 315 | signal(SIGPIPE, fatal_sig_handler); |
| 316 | signal(SIGALRM, fatal_sig_handler); |
| 317 | signal(SIGTERM, fatal_sig_handler); |
| 318 | signal(SIGSEGV, fatal_sig_handler); |
| 319 | signal(SIGUSR1, fatal_sig_handler); |
| 320 | signal(SIGUSR2, fatal_sig_handler); |
| 321 | #ifdef SIGBUS |
| 322 | signal(SIGBUS, fatal_sig_handler); |
| 323 | #endif |
| 324 | #ifdef SIGPOLL |
| 325 | signal(SIGPOLL, fatal_sig_handler); |
| 326 | #endif |
| 327 | #ifdef SIGPROF |
| 328 | signal(SIGPROF, fatal_sig_handler); |
| 329 | #endif |
| 330 | #ifdef SIGSYS |
| 331 | signal(SIGSYS, fatal_sig_handler); |
| 332 | #endif |
| 333 | #ifdef SIGTRAP |
| 334 | signal(SIGTRAP, fatal_sig_handler); |
| 335 | #endif |
| 336 | #ifdef SIGVTALRM |
| 337 | signal(SIGVTALRM, fatal_sig_handler); |
| 338 | #endif |
| 339 | #ifdef SIGXCPU |
| 340 | signal(SIGXCPU, fatal_sig_handler); |
| 341 | #endif |
| 342 | #ifdef SIGXFSZ |
| 343 | signal(SIGXFSZ, fatal_sig_handler); |
| 344 | #endif |
| 345 | #ifdef SIGIO |
| 346 | signal(SIGIO, fatal_sig_handler); |
| 347 | #endif |
| 348 | /* Also clean up utmp on normal exit. */ |
| 349 | atexit(cleanup_utmp); |
| 350 | setup_utmp(pty_name, display); |
| 351 | } |
| 352 | } |
| 353 | } |
| 354 | } else { |
| 355 | close(pipefd[0]); |
| 356 | pty_utmp_helper_pid = pid; |
| 357 | pty_utmp_helper_pipe = pipefd[1]; |
| 358 | signal(SIGCHLD, sigchld_handler); |
| 359 | } |
| 360 | #endif |
| 361 | |
| 362 | /* Drop privs. */ |
| 363 | { |
| 364 | int gid = getgid(), uid = getuid(); |
| 365 | #ifndef HAVE_NO_SETRESUID |
| 366 | int setresgid(gid_t, gid_t, gid_t); |
| 367 | int setresuid(uid_t, uid_t, uid_t); |
| 368 | setresgid(gid, gid, gid); |
| 369 | setresuid(uid, uid, uid); |
| 370 | #else |
| 371 | setgid(getgid()); |
| 372 | setuid(getuid()); |
| 373 | #endif |
| 374 | } |
| 375 | } |
| 376 | |
| 377 | /* |
| 378 | * Called to set up the pty. |
| 379 | * |
| 380 | * Returns an error message, or NULL on success. |
| 381 | * |
| 382 | * Also places the canonical host name into `realhost'. It must be |
| 383 | * freed by the caller. |
| 384 | */ |
| 385 | static char *pty_init(void *frontend, void **backend_handle, |
| 386 | char *host, int port, char **realhost, int nodelay) |
| 387 | { |
| 388 | int slavefd; |
| 389 | pid_t pid, pgrp; |
| 390 | |
| 391 | *backend_handle = NULL; /* we can't sensibly use this, sadly */ |
| 392 | |
| 393 | pty_term_width = cfg.width; |
| 394 | pty_term_height = cfg.height; |
| 395 | |
| 396 | if (pty_master_fd < 0) |
| 397 | pty_open_master(); |
| 398 | |
| 399 | /* |
| 400 | * Set the backspace character to be whichever of ^H and ^? is |
| 401 | * specified by bksp_is_delete. |
| 402 | */ |
| 403 | { |
| 404 | struct termios attrs; |
| 405 | tcgetattr(pty_master_fd, &attrs); |
| 406 | attrs.c_cc[VERASE] = cfg.bksp_is_delete ? '\177' : '\010'; |
| 407 | tcsetattr(pty_master_fd, TCSANOW, &attrs); |
| 408 | } |
| 409 | |
| 410 | /* |
| 411 | * Stamp utmp (that is, tell the utmp helper process to do so), |
| 412 | * or not. |
| 413 | */ |
| 414 | if (!cfg.stamp_utmp) |
| 415 | close(pty_utmp_helper_pipe); /* just let the child process die */ |
| 416 | else { |
| 417 | char *location = get_x_display(); |
| 418 | int len = strlen(location)+1, pos = 0; /* +1 to include NUL */ |
| 419 | while (pos < len) { |
| 420 | int ret = write(pty_utmp_helper_pipe, location+pos, len - pos); |
| 421 | if (ret < 0) { |
| 422 | perror("pterm: writing to utmp helper process"); |
| 423 | close(pty_utmp_helper_pipe); /* arrgh, just give up */ |
| 424 | break; |
| 425 | } |
| 426 | pos += ret; |
| 427 | } |
| 428 | } |
| 429 | |
| 430 | /* |
| 431 | * Fork and execute the command. |
| 432 | */ |
| 433 | pid = fork(); |
| 434 | if (pid < 0) { |
| 435 | perror("fork"); |
| 436 | exit(1); |
| 437 | } |
| 438 | |
| 439 | if (pid == 0) { |
| 440 | int i; |
| 441 | /* |
| 442 | * We are the child. |
| 443 | */ |
| 444 | |
| 445 | slavefd = open(pty_name, O_RDWR); |
| 446 | if (slavefd < 0) { |
| 447 | perror("slave pty: open"); |
| 448 | exit(1); |
| 449 | } |
| 450 | |
| 451 | close(pty_master_fd); |
| 452 | fcntl(slavefd, F_SETFD, 0); /* don't close on exec */ |
| 453 | dup2(slavefd, 0); |
| 454 | dup2(slavefd, 1); |
| 455 | dup2(slavefd, 2); |
| 456 | setsid(); |
| 457 | ioctl(slavefd, TIOCSCTTY, 1); |
| 458 | pgrp = getpid(); |
| 459 | tcsetpgrp(slavefd, pgrp); |
| 460 | setpgrp(); |
| 461 | close(open(pty_name, O_WRONLY, 0)); |
| 462 | setpgrp(); |
| 463 | /* Close everything _else_, for tidiness. */ |
| 464 | for (i = 3; i < 1024; i++) |
| 465 | close(i); |
| 466 | { |
| 467 | char term_env_var[10 + sizeof(cfg.termtype)]; |
| 468 | sprintf(term_env_var, "TERM=%s", cfg.termtype); |
| 469 | putenv(term_env_var); |
| 470 | } |
| 471 | /* |
| 472 | * SIGINT and SIGQUIT may have been set to ignored by our |
| 473 | * parent, particularly by things like sh -c 'pterm &' and |
| 474 | * some window managers. Reverse this for our child process. |
| 475 | */ |
| 476 | signal(SIGINT, SIG_DFL); |
| 477 | signal(SIGQUIT, SIG_DFL); |
| 478 | if (pty_argv) |
| 479 | execvp(pty_argv[0], pty_argv); |
| 480 | else { |
| 481 | char *shell = getenv("SHELL"); |
| 482 | char *shellname; |
| 483 | if (cfg.login_shell) { |
| 484 | char *p = strrchr(shell, '/'); |
| 485 | shellname = smalloc(2+strlen(shell)); |
| 486 | p = p ? p+1 : shell; |
| 487 | sprintf(shellname, "-%s", p); |
| 488 | } else |
| 489 | shellname = shell; |
| 490 | execl(getenv("SHELL"), shellname, NULL); |
| 491 | } |
| 492 | |
| 493 | /* |
| 494 | * If we're here, exec has gone badly foom. |
| 495 | */ |
| 496 | perror("exec"); |
| 497 | exit(127); |
| 498 | } else { |
| 499 | close(slavefd); |
| 500 | pty_child_pid = pid; |
| 501 | pty_child_dead = FALSE; |
| 502 | signal(SIGCHLD, sigchld_handler); |
| 503 | } |
| 504 | |
| 505 | return NULL; |
| 506 | } |
| 507 | |
| 508 | /* |
| 509 | * Called to send data down the pty. |
| 510 | */ |
| 511 | static int pty_send(void *handle, char *buf, int len) |
| 512 | { |
| 513 | if (pty_master_fd < 0) |
| 514 | return 0; /* ignore all writes if fd closed */ |
| 515 | |
| 516 | while (len > 0) { |
| 517 | int ret = write(pty_master_fd, buf, len); |
| 518 | if (ret < 0) { |
| 519 | perror("write pty master"); |
| 520 | exit(1); |
| 521 | } |
| 522 | buf += ret; |
| 523 | len -= ret; |
| 524 | } |
| 525 | return 0; |
| 526 | } |
| 527 | |
| 528 | void pty_close(void) |
| 529 | { |
| 530 | if (pty_master_fd >= 0) { |
| 531 | close(pty_master_fd); |
| 532 | pty_master_fd = -1; |
| 533 | } |
| 534 | close(pty_utmp_helper_pipe); /* this causes utmp to be cleaned up */ |
| 535 | } |
| 536 | |
| 537 | /* |
| 538 | * Called to query the current socket sendability status. |
| 539 | */ |
| 540 | static int pty_sendbuffer(void *handle) |
| 541 | { |
| 542 | return 0; |
| 543 | } |
| 544 | |
| 545 | /* |
| 546 | * Called to set the size of the window |
| 547 | */ |
| 548 | static void pty_size(void *handle, int width, int height) |
| 549 | { |
| 550 | struct winsize size; |
| 551 | |
| 552 | pty_term_width = width; |
| 553 | pty_term_height = height; |
| 554 | |
| 555 | size.ws_row = (unsigned short)pty_term_height; |
| 556 | size.ws_col = (unsigned short)pty_term_width; |
| 557 | size.ws_xpixel = (unsigned short) pty_term_width * font_dimension(0); |
| 558 | size.ws_ypixel = (unsigned short) pty_term_height * font_dimension(1); |
| 559 | ioctl(pty_master_fd, TIOCSWINSZ, (void *)&size); |
| 560 | return; |
| 561 | } |
| 562 | |
| 563 | /* |
| 564 | * Send special codes. |
| 565 | */ |
| 566 | static void pty_special(void *handle, Telnet_Special code) |
| 567 | { |
| 568 | /* Do nothing! */ |
| 569 | return; |
| 570 | } |
| 571 | |
| 572 | static Socket pty_socket(void *handle) |
| 573 | { |
| 574 | return NULL; /* shouldn't ever be needed */ |
| 575 | } |
| 576 | |
| 577 | static int pty_sendok(void *handle) |
| 578 | { |
| 579 | return 1; |
| 580 | } |
| 581 | |
| 582 | static void pty_unthrottle(void *handle, int backlog) |
| 583 | { |
| 584 | /* do nothing */ |
| 585 | } |
| 586 | |
| 587 | static int pty_ldisc(void *handle, int option) |
| 588 | { |
| 589 | return 0; /* neither editing nor echoing */ |
| 590 | } |
| 591 | |
| 592 | static int pty_exitcode(void *handle) |
| 593 | { |
| 594 | if (!pty_child_dead) |
| 595 | return -1; /* not dead yet */ |
| 596 | else |
| 597 | return pty_exit_code; |
| 598 | } |
| 599 | |
| 600 | Backend pty_backend = { |
| 601 | pty_init, |
| 602 | pty_send, |
| 603 | pty_sendbuffer, |
| 604 | pty_size, |
| 605 | pty_special, |
| 606 | pty_socket, |
| 607 | pty_exitcode, |
| 608 | pty_sendok, |
| 609 | pty_ldisc, |
| 610 | pty_unthrottle, |
| 611 | 1 |
| 612 | }; |