libexec/getty/main.c

   1 /*-
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#) Copyright (c) 1980, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)from: main.c     8.1 (Berkeley) 6/20/93
  31  * $FreeBSD: src/libexec/getty/main.c,v 1.28.2.4 2003/02/06 11:45:31 sobomax Exp $
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/stat.h>
  36 #include <sys/ioctl.h>
  37 #include <sys/resource.h>
  38 #include <sys/ttydefaults.h>
  39 #include <sys/utsname.h>
  40 #include <ctype.h>
  41 #include <errno.h>
  42 #include <fcntl.h>
  43 #include <locale.h>
  44 #include <libutil.h>
  45 #include <signal.h>
  46 #include <setjmp.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <syslog.h>
  50 #include <termios.h>
  51 #include <time.h>
  52 #include <unistd.h>
  53
  54 #include "gettytab.h"
  55 #include "pathnames.h"
  56 #include "extern.h"
  57
  58 /*
  59  * Set the amount of running time that getty should accumulate
  60  * before deciding that something is wrong and exit.
  61  */
  62 #define GETTY_TIMEOUT   60 /* seconds */
  63
  64 #undef CTRL
  65 #define CTRL(x)  (x&037)
  66
  67 /* defines for auto detection of incoming PPP calls (->PAP/CHAP) */
  68
  69 #define PPP_FRAME           0x7e  /* PPP Framing character */
  70 #define PPP_STATION         0xff  /* "All Station" character */
  71 #define PPP_ESCAPE          0x7d  /* Escape Character */
  72 #define PPP_CONTROL         0x03  /* PPP Control Field */
  73 #define PPP_CONTROL_ESCAPED 0x23  /* PPP Control Field, escaped */
  74 #define PPP_LCP_HI          0xc0  /* LCP protocol - high byte */
  75 #define PPP_LCP_LOW         0x21  /* LCP protocol - low byte */
  76
  77 struct termios tmode, omode;
  78
  79 int crmod, digit, lower, upper;
  80
  81 char    hostname[MAXHOSTNAMELEN];
  82 char    name[MAXLOGNAME*3];
  83 char    dev[] = _PATH_DEV;
  84 char    ttyn[32];
  85
  86 #define OBUFSIZ         128
  87 #define TABBUFSIZ       512
  88
  89 char    defent[TABBUFSIZ];
  90 char    tabent[TABBUFSIZ];
  91
  92 char    *env[128];
  93
  94 char partab[] = {
  95         0001,0201,0201,0001,0201,0001,0001,0201,
  96         0202,0004,0003,0205,0005,0206,0201,0001,
  97         0201,0001,0001,0201,0001,0201,0201,0001,
  98         0001,0201,0201,0001,0201,0001,0001,0201,
  99         0200,0000,0000,0200,0000,0200,0200,0000,
 100         0000,0200,0200,0000,0200,0000,0000,0200,
 101         0000,0200,0200,0000,0200,0000,0000,0200,
 102         0200,0000,0000,0200,0000,0200,0200,0000,
 103         0200,0000,0000,0200,0000,0200,0200,0000,
 104         0000,0200,0200,0000,0200,0000,0000,0200,
 105         0000,0200,0200,0000,0200,0000,0000,0200,
 106         0200,0000,0000,0200,0000,0200,0200,0000,
 107         0000,0200,0200,0000,0200,0000,0000,0200,
 108         0200,0000,0000,0200,0000,0200,0200,0000,
 109         0200,0000,0000,0200,0000,0200,0200,0000,
 110         0000,0200,0200,0000,0200,0000,0000,0201
 111 };
 112
 113 #define ERASE   tmode.c_cc[VERASE]
 114 #define KILL    tmode.c_cc[VKILL]
 115 #define EOT     tmode.c_cc[VEOF]
 116
 117 #define puts    Gputs
 118
 119 static void     dingdong(int);
 120 static int      getname(void);
 121 static void     interrupt(int);
 122 static void     oflush(void);
 123 static void     prompt(void);
 124 static void     putchr(int);
 125 static void     putf(const char *);
 126 static void     putpad(const char *);
 127 static void     puts(const char *);
 128 static void     timeoverrun(int);
 129 static char     *get_line(int);
 130 static void     setttymode(const char *, int);
 131 static void     setdefttymode(const char *);
 132 static int      opentty(const char *, int);
 133
 134 jmp_buf timeout;
 135
 136 static void
 137 dingdong(int signo)
 138 {
 139         alarm(0);
 140         longjmp(timeout, 1);
 141 }
 142
 143 jmp_buf intrupt;
 144
 145 static void
 146 interrupt(int signo)
 147 {
 148         longjmp(intrupt, 1);
 149 }
 150
 151 /*
 152  * Action to take when getty is running too long.
 153  */
 154 static void
 155 timeoverrun(int signo)
 156 {
 157         syslog(LOG_ERR, "getty exiting due to excessive running time");
 158         exit(1);
 159 }
 160
 161 int
 162 main(int argc, char **argv)
 163 {
 164         extern  char **environ;
 165         const char *tname;
 166         int first_sleep = 1, first_time = 1;
 167         struct rlimit limit;
 168         int rval;
 169
 170         signal(SIGINT, SIG_IGN);
 171         signal(SIGQUIT, SIG_IGN);
 172
 173         openlog("getty", LOG_ODELAY|LOG_CONS|LOG_PID, LOG_AUTH);
 174         gethostname(hostname, sizeof(hostname) - 1);
 175         hostname[sizeof(hostname) - 1] = '\0';
 176         if (hostname[0] == '\0')
 177                 strcpy(hostname, "Amnesiac");
 178
 179         /*
 180          * Limit running time to deal with broken or dead lines.
 181          */
 182         (void)signal(SIGXCPU, timeoverrun);
 183         limit.rlim_max = RLIM_INFINITY;
 184         limit.rlim_cur = GETTY_TIMEOUT;
 185         (void)setrlimit(RLIMIT_CPU, &limit);
 186
 187         gettable("default", defent);
 188         gendefaults();
 189         tname = "default";
 190         if (argc > 1)
 191                 tname = argv[1];
 192
 193         /*
 194          * The following is a work around for vhangup interactions
 195          * which cause great problems getting window systems started.
 196          * If the tty line is "-", we do the old style getty presuming
 197          * that the file descriptors are already set up for us.
 198          * J. Gettys - MIT Project Athena.
 199          */
 200         if (argc <= 2 || strcmp(argv[2], "-") == 0)
 201             strcpy(ttyn, ttyname(STDIN_FILENO));
 202         else {
 203             strcpy(ttyn, dev);
 204             strncat(ttyn, argv[2], sizeof(ttyn)-sizeof(dev));
 205             if (strcmp(argv[0], "+") != 0) {
 206                 chown(ttyn, 0, 0);
 207                 chmod(ttyn, 0600);
 208                 revoke(ttyn);
 209
 210                 gettable(tname, tabent);
 211
 212                 /* Init modem sequence has been specified
 213                  */
 214                 if (IC) {
 215                         if (!opentty(ttyn, O_RDWR|O_NONBLOCK))
 216                                 exit(1);
 217                         setdefttymode(tname);
 218                         if (getty_chat(IC, CT, DC) > 0) {
 219                                 syslog(LOG_ERR, "modem init problem on %s", ttyn);
 220                                 (void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
 221                                 exit(1);
 222                         }
 223                 }
 224
 225                 if (AC) {
 226                         int i, rfds;
 227                         struct timeval timeout;
 228
 229                         if (!opentty(ttyn, O_RDWR|O_NONBLOCK))
 230                                 exit(1);
 231                         setdefttymode(tname);
 232                         rfds = 1 << 0;  /* FD_SET */
 233                         timeout.tv_sec = RT;
 234                         timeout.tv_usec = 0;
 235                         i = select(32, (fd_set*)&rfds, NULL,
 236                                        NULL, RT ? &timeout : NULL);
 237                         if (i < 0) {
 238                                 syslog(LOG_ERR, "select %s: %m", ttyn);
 239                         } else if (i == 0) {
 240                                 syslog(LOG_NOTICE, "recycle tty %s", ttyn);
 241                                 (void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
 242                                 exit(0);  /* recycle for init */
 243                         }
 244                         i = getty_chat(AC, CT, DC);
 245                         if (i > 0) {
 246                                 syslog(LOG_ERR, "modem answer problem on %s", ttyn);
 247                                 (void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
 248                                 exit(1);
 249                         }
 250                 } else { /* maybe blocking open */
 251                         if (!opentty(ttyn, O_RDWR | (NC ? O_NONBLOCK : 0 )))
 252                                 exit(1);
 253                 }
 254             }
 255         }
 256
 257         /* Start with default tty settings */
 258         if (tcgetattr(STDIN_FILENO, &tmode) < 0) {
 259                 syslog(LOG_ERR, "tcgetattr %s: %m", ttyn);
 260                 exit(1);
 261         }
 262         /*
 263          * Don't rely on the driver too much, and initialize crucial
 264          * things according to <sys/ttydefaults.h>.  Avoid clobbering
 265          * the c_cc[] settings however, the console drivers might wish
 266          * to leave their idea of the preferred VERASE key value
 267          * there.
 268          */
 269         tmode.c_iflag = TTYDEF_IFLAG;
 270         tmode.c_oflag = TTYDEF_OFLAG;
 271         tmode.c_lflag = TTYDEF_LFLAG;
 272         tmode.c_cflag = TTYDEF_CFLAG;
 273         tmode.c_cflag |= (NC ? CLOCAL : 0);
 274         omode = tmode;
 275
 276         for (;;) {
 277
 278                 /*
 279                  * if a delay was specified then sleep for that
 280                  * number of seconds before writing the initial prompt
 281                  */
 282                 if (first_sleep && DE) {
 283                     sleep(DE);
 284                     /* remove any noise */
 285                     (void)tcflush(STDIN_FILENO, TCIOFLUSH);
 286                 }
 287                 first_sleep = 0;
 288
 289                 setttymode(tname, 0);
 290                 if (AB) {
 291                         tname = autobaud();
 292                         continue;
 293                 }
 294                 if (PS) {
 295                         tname = portselector();
 296                         continue;
 297                 }
 298                 if (CL && *CL)
 299                         putpad(CL);
 300                 edithost(HE);
 301
 302                 /* if this is the first time through this, and an
 303                    issue file has been given, then send it */
 304                 if (first_time && IF) {
 305                         int fd;
 306
 307                         if ((fd = open(IF, O_RDONLY)) != -1) {
 308                                 char * cp;
 309
 310                                 while ((cp = get_line(fd)) != NULL) {
 311                                           putf(cp);
 312                                 }
 313                                 close(fd);
 314                         }
 315                 }
 316                 first_time = 0;
 317
 318                 if (IM && *IM && !(PL && PP))
 319                         putf(IM);
 320                 if (setjmp(timeout)) {
 321                         cfsetispeed(&tmode, B0);
 322                         cfsetospeed(&tmode, B0);
 323                         (void)tcsetattr(STDIN_FILENO, TCSANOW, &tmode);
 324                         exit(1);
 325                 }
 326                 if (TO) {
 327                         signal(SIGALRM, dingdong);
 328                         alarm(TO);
 329                 }
 330                 if (AL) {
 331                         const char *p = AL;
 332                         char *q = name;
 333
 334                         while (*p && q < &name[sizeof name - 1]) {
 335                                 if (isupper(*p))
 336                                         upper = 1;
 337                                 else if (islower(*p))
 338                                         lower = 1;
 339                                 else if (isdigit(*p))
 340                                         digit++;
 341                                 *q++ = *p++;
 342                         }
 343                 } else if (!(PL && PP))
 344                         rval = getname();
 345                 if (rval == 2 || (PL && PP)) {
 346                         oflush();
 347                         alarm(0);
 348                         limit.rlim_max = RLIM_INFINITY;
 349                         limit.rlim_cur = RLIM_INFINITY;
 350                         (void)setrlimit(RLIMIT_CPU, &limit);
 351                         execle(PP, "ppplogin", ttyn, NULL, env);
 352                         syslog(LOG_ERR, "%s: %m", PP);
 353                         exit(1);
 354                 } else if (rval || AL) {
 355                         int i;
 356
 357                         oflush();
 358                         alarm(0);
 359                         signal(SIGALRM, SIG_DFL);
 360                         if (name[0] == '-') {
 361                                 puts("user names may not start with '-'.");
 362                                 continue;
 363                         }
 364                         if (!(upper || lower || digit))
 365                                 continue;
 366                         set_flags(2);
 367                         if (crmod) {
 368                                 tmode.c_iflag |= ICRNL;
 369                                 tmode.c_oflag |= ONLCR;
 370                         }
 371 #if REALLY_OLD_TTYS
 372                         if (upper || UC)
 373                                 tmode.sg_flags |= LCASE;
 374                         if (lower || LC)
 375                                 tmode.sg_flags &= ~LCASE;
 376 #endif
 377                         if (tcsetattr(STDIN_FILENO, TCSANOW, &tmode) < 0) {
 378                                 syslog(LOG_ERR, "tcsetattr %s: %m", ttyn);
 379                                 exit(1);
 380                         }
 381                         signal(SIGINT, SIG_DFL);
 382                         for (i = 0; environ[i] != NULL; i++)
 383                                 env[i] = environ[i];
 384                         makeenv(&env[i]);
 385
 386                         limit.rlim_max = RLIM_INFINITY;
 387                         limit.rlim_cur = RLIM_INFINITY;
 388                         (void)setrlimit(RLIMIT_CPU, &limit);
 389                         execle(LO, "login", AL ? "-fp" : "-p", name,
 390                             NULL, env);
 391                         syslog(LOG_ERR, "%s: %m", LO);
 392                         exit(1);
 393                 }
 394                 alarm(0);
 395                 signal(SIGALRM, SIG_DFL);
 396                 signal(SIGINT, SIG_IGN);
 397                 if (NX && *NX)
 398                         tname = NX;
 399         }
 400 }
 401
 402 static int
 403 opentty(const char *ttyn, int flags)
 404 {
 405         int i, j = 0;
 406         int failopenlogged = 0;
 407
 408         while (j < 10 && (i = open(ttyn, flags)) == -1)
 409         {
 410                 if (((j % 10) == 0) && (errno != ENXIO || !failopenlogged)) {
 411                         syslog(LOG_ERR, "open %s: %m", ttyn);
 412                         failopenlogged = 1;
 413                 }
 414                 j++;
 415                 sleep(60);
 416         }
 417         if (i == -1) {
 418                 syslog(LOG_ERR, "open %s: %m", ttyn);
 419                 return 0;
 420         }
 421         else {
 422                 if (login_tty(i) < 0) {
 423                         if (daemon(0,0) < 0) {
 424                                 syslog(LOG_ERR,"daemon: %m");
 425                                 close(i);
 426                                 return 0;
 427                         }
 428                         if (login_tty(i) < 0) {
 429                                 syslog(LOG_ERR, "login_tty %s: %m", ttyn);
 430                                 close(i);
 431                                 return 0;
 432                         }
 433                 }
 434                 return 1;
 435         }
 436 }
 437
 438 static void
 439 setdefttymode(const char *tname)
 440 {
 441         if (tcgetattr(STDIN_FILENO, &tmode) < 0) {
 442                 syslog(LOG_ERR, "tcgetattr %s: %m", ttyn);
 443                 exit(1);
 444         }
 445         tmode.c_iflag = TTYDEF_IFLAG;
 446         tmode.c_oflag = TTYDEF_OFLAG;
 447         tmode.c_lflag = TTYDEF_LFLAG;
 448         tmode.c_cflag = TTYDEF_CFLAG;
 449         omode = tmode;
 450         setttymode(tname, 1);
 451 }
 452
 453 static void
 454 setttymode(const char *tname, int raw)
 455 {
 456         int off = 0;
 457
 458         gettable(tname, tabent);
 459         if (OPset || EPset || APset)
 460                 APset++, OPset++, EPset++;
 461         setdefaults();
 462         (void)tcflush(STDIN_FILENO, TCIOFLUSH); /* clear out the crap */
 463         ioctl(STDIN_FILENO, FIONBIO, &off);     /* turn off non-blocking mode */
 464         ioctl(STDIN_FILENO, FIOASYNC, &off);    /* ditto for async mode */
 465
 466         if (IS)
 467                 cfsetispeed(&tmode, speed(IS));
 468         else if (SP)
 469                 cfsetispeed(&tmode, speed(SP));
 470         if (OS)
 471                 cfsetospeed(&tmode, speed(OS));
 472         else if (SP)
 473                 cfsetospeed(&tmode, speed(SP));
 474         set_flags(0);
 475         setchars();
 476         if (raw)
 477                 cfmakeraw(&tmode);
 478         if (tcsetattr(STDIN_FILENO, TCSANOW, &tmode) < 0) {
 479                 syslog(LOG_ERR, "tcsetattr %s: %m", ttyn);
 480                 exit(1);
 481         }
 482 }
 483
 484
 485 static int
 486 getname(void)
 487 {
 488         int c;
 489         char *np;
 490         unsigned char cs;
 491         int ppp_state = 0;
 492         int ppp_connection = 0;
 493
 494         /*
 495          * Interrupt may happen if we use CBREAK mode
 496          */
 497         if (setjmp(intrupt)) {
 498                 signal(SIGINT, SIG_IGN);
 499                 return (0);
 500         }
 501         signal(SIGINT, interrupt);
 502         set_flags(1);
 503         prompt();
 504         oflush();
 505         if (PF > 0) {
 506                 sleep(PF);
 507                 PF = 0;
 508         }
 509         if (tcsetattr(STDIN_FILENO, TCSANOW, &tmode) < 0) {
 510                 syslog(LOG_ERR, "%s: %m", ttyn);
 511                 exit(1);
 512         }
 513         crmod = digit = lower = upper = 0;
 514         np = name;
 515         for (;;) {
 516                 oflush();
 517                 if (read(STDIN_FILENO, &cs, 1) <= 0)
 518                         exit(0);
 519                 if ((c = cs&0177) == 0)
 520                         return (0);
 521
 522                 /* PPP detection state machine..
 523                    Look for sequences:
 524                    PPP_FRAME, PPP_STATION, PPP_ESCAPE, PPP_CONTROL_ESCAPED or
 525                    PPP_FRAME, PPP_STATION, PPP_CONTROL (deviant from RFC)
 526                    See RFC1662.
 527                    Derived from code from Michael Hancock, <michaelh@cet.co.jp>
 528                    and Erik 'PPP' Olson, <eriko@wrq.com>
 529                  */
 530
 531                 if (PP && (cs == PPP_FRAME)) {
 532                         ppp_state = 1;
 533                 } else if (ppp_state == 1 && cs == PPP_STATION) {
 534                         ppp_state = 2;
 535                 } else if (ppp_state == 2 && cs == PPP_ESCAPE) {
 536                         ppp_state = 3;
 537                 } else if ((ppp_state == 2 && cs == PPP_CONTROL)
 538                         || (ppp_state == 3 && cs == PPP_CONTROL_ESCAPED)) {
 539                         ppp_state = 4;
 540                 } else if (ppp_state == 4 && cs == PPP_LCP_HI) {
 541                         ppp_state = 5;
 542                 } else if (ppp_state == 5 && cs == PPP_LCP_LOW) {
 543                         ppp_connection = 1;
 544                         break;
 545                 } else {
 546                         ppp_state = 0;
 547                 }
 548
 549                 if (c == EOT || c == CTRL('d'))
 550                         exit(1);
 551                 if (c == '\r' || c == '\n' || np >= &name[sizeof name-1]) {
 552                         putf("\r\n");
 553                         break;
 554                 }
 555                 if (islower(c))
 556                         lower = 1;
 557                 else if (isupper(c))
 558                         upper = 1;
 559                 else if (c == ERASE || c == '\b' || c == 0177) {
 560                         if (np > name) {
 561                                 np--;
 562                                 if (cfgetospeed(&tmode) >= 1200)
 563                                         puts("\b \b");
 564                                 else
 565                                         putchr(cs);
 566                         }
 567                         continue;
 568                 } else if (c == KILL || c == CTRL('u')) {
 569                         putchr('\r');
 570                         if (cfgetospeed(&tmode) < 1200)
 571                                 putchr('\n');
 572                         /* this is the way they do it down under ... */
 573                         else if (np > name)
 574                                 puts("                                     \r");
 575                         prompt();
 576                         np = name;
 577                         continue;
 578                 } else if (isdigit(c))
 579                         digit++;
 580                 if (IG && (c <= ' ' || c > 0176))
 581                         continue;
 582                 *np++ = c;
 583                 putchr(cs);
 584         }
 585         signal(SIGINT, SIG_IGN);
 586         *np = 0;
 587         if (c == '\r')
 588                 crmod = 1;
 589         if ((upper && !lower && !LC) || UC)
 590                 for (np = name; *np; np++)
 591                         if (isupper(*np))
 592                                 *np = tolower(*np);
 593         return (1 + ppp_connection);
 594 }
 595
 596 static void
 597 putpad(const char *s)
 598 {
 599         int pad = 0;
 600         speed_t ospeed;
 601
 602         ospeed = cfgetospeed(&tmode);
 603
 604         if (isdigit(*s)) {
 605                 while (isdigit(*s)) {
 606                         pad *= 10;
 607                         pad += *s++ - '0';
 608                 }
 609                 pad *= 10;
 610                 if (*s == '.' && isdigit(s[1])) {
 611                         pad += s[1] - '0';
 612                         s += 2;
 613                 }
 614         }
 615
 616         puts(s);
 617         /*
 618          * If no delay needed, or output speed is
 619          * not comprehensible, then don't try to delay.
 620          */
 621         if (pad == 0 || ospeed <= 0)
 622                 return;
 623
 624         /*
 625          * Round up by a half a character frame, and then do the delay.
 626          * Too bad there are no user program accessible programmed delays.
 627          * Transmitting pad characters slows many terminals down and also
 628          * loads the system.
 629          */
 630         pad = (pad * ospeed + 50000) / 100000;
 631         while (pad--)
 632                 putchr(*PC);
 633 }
 634
 635 static void
 636 puts(const char *s)
 637 {
 638         while (*s)
 639                 putchr(*s++);
 640 }
 641
 642 char    outbuf[OBUFSIZ];
 643 int     obufcnt = 0;
 644
 645 static void
 646 putchr(int cc)
 647 {
 648         char c;
 649
 650         c = cc;
 651         if (!NP) {
 652                 c |= partab[c&0177] & 0200;
 653                 if (OP)
 654                         c ^= 0200;
 655         }
 656         if (!UB) {
 657                 outbuf[obufcnt++] = c;
 658                 if (obufcnt >= OBUFSIZ)
 659                         oflush();
 660         } else
 661                 write(STDOUT_FILENO, &c, 1);
 662 }
 663
 664 static void
 665 oflush(void)
 666 {
 667         if (obufcnt)
 668                 write(STDOUT_FILENO, outbuf, obufcnt);
 669         obufcnt = 0;
 670 }
 671
 672 static void
 673 prompt(void)
 674 {
 675         putf(LM);
 676         if (CO)
 677                 putchr('\n');
 678 }
 679
 680
 681 static char *
 682 get_line(int fd)
 683 {
 684         int i = 0;
 685         static char linebuf[512];
 686
 687         /*
 688          * This is certainly slow, but it avoids having to include
 689          * stdio.h unnecessarily. Issue files should be small anyway.
 690          */
 691         while (i < (sizeof linebuf - 3) && read(fd, linebuf+i, 1)==1) {
 692                 if (linebuf[i] == '\n') {
 693                         /* Don't rely on newline mode, assume raw */
 694                         linebuf[i++] = '\r';
 695                         linebuf[i++] = '\n';
 696                         linebuf[i] = '\0';
 697                         return linebuf;
 698                 }
 699                 ++i;
 700         }
 701         linebuf[i] = '\0';
 702         return i ? linebuf : 0;
 703 }
 704
 705 static void
 706 putf(const char *cp)
 707 {
 708         extern char editedhost[];
 709         time_t t;
 710         char *slash, db[100];
 711
 712         static struct utsname kerninfo;
 713
 714         if (!*kerninfo.sysname)
 715                 uname(&kerninfo);
 716
 717         while (*cp) {
 718                 if (*cp != '%') {
 719                         putchr(*cp++);
 720                         continue;
 721                 }
 722                 switch (*++cp) {
 723
 724                 case 't':
 725                         slash = strrchr(ttyn, '/');
 726                         if (slash == NULL)
 727                                 puts(ttyn);
 728                         else
 729                                 puts(&slash[1]);
 730                         break;
 731
 732                 case 'h':
 733                         puts(editedhost);
 734                         break;
 735
 736                 case 'd': {
 737                         t = (time_t)0;
 738                         (void)time(&t);
 739                         if (Lo)
 740                                 (void)setlocale(LC_TIME, Lo);
 741                         (void)strftime(db, sizeof(db), DF, localtime(&t));
 742                         puts(db);
 743                         break;
 744
 745                 case 's':
 746                         puts(kerninfo.sysname);
 747                         break;
 748
 749                 case 'm':
 750                         puts(kerninfo.machine);
 751                         break;
 752
 753                 case 'r':
 754                         puts(kerninfo.release);
 755                         break;
 756
 757                 case 'v':
 758                         puts(kerninfo.version);
 759                         break;
 760                 }
 761
 762                 case '%':
 763                         putchr('%');
 764                         break;
 765                 }
 766                 cp++;
 767         }
 768 }