release/src/router/ppp/chat/chat.c

   1 /*
   2  *      Chat -- a program for automatic session establishment (i.e. dial
   3  *              the phone and log in).
   4  *
   5  * Standard termination codes:
   6  *  0 - successful completion of the script
   7  *  1 - invalid argument, expect string too large, etc.
   8  *  2 - error on an I/O operation or fatal error condition.
   9  *  3 - timeout waiting for a simple string.
  10  *  4 - the first string declared as "ABORT"
  11  *  5 - the second string declared as "ABORT"
  12  *  6 - ... and so on for successive ABORT strings.
  13  *
  14  *      This software is in the public domain.
  15  *
  16  * -----------------
  17  *      22-May-99 added environment substitutuion, enabled with -E switch.
  18  *      Andreas Arens <andras@cityweb.de>.
  19  *
  20  *      12-May-99 added a feature to read data to be sent from a file,
  21  *      if the send string starts with @.  Idea from gpk <gpk@onramp.net>.
  22  *
  23  *      added -T and -U option and \T and \U substitution to pass a phone
  24  *      number into chat script. Two are needed for some ISDN TA applications.
  25  *      Keith Dart <kdart@cisco.com>
  26  *
  27  *
  28  *      Added SAY keyword to send output to stderr.
  29  *      This allows to turn ECHO OFF and to output specific, user selected,
  30  *      text to give progress messages. This best works when stderr
  31  *      exists (i.e.: pppd in nodetach mode).
  32  *
  33  *      Added HANGUP directives to allow for us to be called
  34  *      back. When HANGUP is set to NO, chat will not hangup at HUP signal.
  35  *      We rely on timeouts in that case.
  36  *
  37  *      Added CLR_ABORT to clear previously set ABORT string. This has been
  38  *      dictated by the HANGUP above as "NO CARRIER" (for example) must be
  39  *      an ABORT condition until we know the other host is going to close
  40  *      the connection for call back. As soon as we have completed the
  41  *      first stage of the call back sequence, "NO CARRIER" is a valid, non
  42  *      fatal string. As soon as we got called back (probably get "CONNECT"),
  43  *      we should re-arm the ABORT "NO CARRIER". Hence the CLR_ABORT command.
  44  *      Note that CLR_ABORT packs the abort_strings[] array so that we do not
  45  *      have unused entries not being reclaimed.
  46  *
  47  *      In the same vein as above, added CLR_REPORT keyword.
  48  *
  49  *      Allow for comments. Line starting with '#' are comments and are
  50  *      ignored. If a '#' is to be expected as the first character, the
  51  *      expect string must be quoted.
  52  *
  53  *
  54  *              Francis Demierre <Francis@SwissMail.Com>
  55  *              Thu May 15 17:15:40 MET DST 1997
  56  *
  57  *
  58  *      Added -r "report file" switch & REPORT keyword.
  59  *              Robert Geer <bgeer@xmission.com>
  60  *
  61  *      Added -s "use stderr" and -S "don't use syslog" switches.
  62  *              June 18, 1997
  63  *              Karl O. Pinc <kop@meme.com>
  64  *
  65  *
  66  *      Added -e "echo" switch & ECHO keyword
  67  *              Dick Streefland <dicks@tasking.nl>
  68  *
  69  *
  70  *      Considerable updates and modifications by
  71  *              Al Longyear <longyear@pobox.com>
  72  *              Paul Mackerras <paulus@cs.anu.edu.au>
  73  *
  74  *
  75  *      The original author is:
  76  *
  77  *              Karl Fox <karl@MorningStar.Com>
  78  *              Morning Star Technologies, Inc.
  79  *              1760 Zollinger Road
  80  *              Columbus, OH  43221
  81  *              (614)451-1883
  82  *
  83  */
  84
  85 #ifndef __STDC__
  86 #define const
  87 #endif
  88
  89 #ifndef lint
  90 static const char rcsid[] = "$Id: chat.c,v 1.1.1.4 2003/10/14 08:09:52 sparq Exp $";
  91 #endif
  92
  93 #include <stdio.h>
  94 #include <ctype.h>
  95 #include <time.h>
  96 #include <fcntl.h>
  97 #include <signal.h>
  98 #include <errno.h>
  99 #include <string.h>
 100 #include <stdlib.h>
 101 #include <unistd.h>
 102 #include <sys/types.h>
 103 #include <sys/stat.h>
 104 #include <syslog.h>
 105
 106 #ifndef TERMIO
 107 #undef  TERMIOS
 108 #define TERMIOS
 109 #endif
 110
 111 #ifdef TERMIO
 112 #include <termio.h>
 113 #endif
 114 #ifdef TERMIOS
 115 #include <termios.h>
 116 #endif
 117
 118 #define STR_LEN 1024
 119
 120 #ifndef SIGTYPE
 121 #define SIGTYPE void
 122 #endif
 123
 124 #undef __P
 125 #undef __V
 126
 127 #ifdef __STDC__
 128 #include <stdarg.h>
 129 #define __V(x)  x
 130 #define __P(x)  x
 131 #else
 132 #include <varargs.h>
 133 #define __V(x)  (va_alist) va_dcl
 134 #define __P(x)  ()
 135 #define const
 136 #endif
 137
 138 #ifndef O_NONBLOCK
 139 #define O_NONBLOCK      O_NDELAY
 140 #endif
 141
 142 #ifdef SUNOS
 143 extern int sys_nerr;
 144 extern char *sys_errlist[];
 145 #define memmove(to, from, n)    bcopy(from, to, n)
 146 #define strerror(n)             ((unsigned)(n) < sys_nerr? sys_errlist[(n)] :\
 147                                  "unknown error")
 148 #endif
 149
 150 /*************** Micro getopt() *********************************************/
 151 #define OPTION(c,v)     (_O&2&&**v?*(*v)++:!c||_O&4?0:(!(_O&1)&& \
 152                                 (--c,++v),_O=4,c&&**v=='-'&&v[0][1]?*++*v=='-'\
 153                                 &&!v[0][1]?(--c,++v,0):(_O=2,*(*v)++):0))
 154 #define OPTARG(c,v)     (_O&2?**v||(++v,--c)?(_O=1,--c,*v++): \
 155                                 (_O=4,(char*)0):(char*)0)
 156 #define OPTONLYARG(c,v) (_O&2&&**v?(_O=1,--c,*v++):(char*)0)
 157 #define ARG(c,v)        (c?(--c,*v++):(char*)0)
 158
 159 static int _O = 0;              /* Internal state */
 160 /*************** Micro getopt() *********************************************/
 161
 162 char *program_name;
 163
 164 #define MAX_ABORTS              50
 165 #define MAX_REPORTS             50
 166 #define DEFAULT_CHAT_TIMEOUT    45
 167
 168 int echo          = 0;
 169 int verbose       = 0;
 170 int to_log        = 1;
 171 int to_stderr     = 0;
 172 int Verbose       = 0;
 173 int quiet         = 0;
 174 int report        = 0;
 175 int use_env       = 0;
 176 int exit_code     = 0;
 177 FILE* report_fp   = (FILE *) 0;
 178 char *report_file = (char *) 0;
 179 char *chat_file   = (char *) 0;
 180 char *phone_num   = (char *) 0;
 181 char *phone_num2  = (char *) 0;
 182 int timeout       = DEFAULT_CHAT_TIMEOUT;
 183
 184 int have_tty_parameters = 0;
 185
 186 #ifdef TERMIO
 187 #define term_parms struct termio
 188 #define get_term_param(param) ioctl(0, TCGETA, param)
 189 #define set_term_param(param) ioctl(0, TCSETA, param)
 190 struct termio saved_tty_parameters;
 191 #endif
 192
 193 #ifdef TERMIOS
 194 #define term_parms struct termios
 195 #define get_term_param(param) tcgetattr(0, param)
 196 #define set_term_param(param) tcsetattr(0, TCSANOW, param)
 197 struct termios saved_tty_parameters;
 198 #endif
 199
 200 char *abort_string[MAX_ABORTS], *fail_reason = (char *)0,
 201         fail_buffer[50];
 202 int n_aborts = 0, abort_next = 0, timeout_next = 0, echo_next = 0;
 203 int clear_abort_next = 0;
 204
 205 char *report_string[MAX_REPORTS] ;
 206 char  report_buffer[50] ;
 207 int n_reports = 0, report_next = 0, report_gathering = 0 ;
 208 int clear_report_next = 0;
 209
 210 int say_next = 0, hup_next = 0;
 211
 212 void *dup_mem __P((void *b, size_t c));
 213 void *copy_of __P((char *s));
 214 void usage __P((void));
 215 void logf __P((const char *fmt, ...));
 216 void fatal __P((int code, const char *fmt, ...));
 217 SIGTYPE sigalrm __P((int signo));
 218 SIGTYPE sigint __P((int signo));
 219 SIGTYPE sigterm __P((int signo));
 220 SIGTYPE sighup __P((int signo));
 221 void unalarm __P((void));
 222 void init __P((void));
 223 void set_tty_parameters __P((void));
 224 void echo_stderr __P((int));
 225 void break_sequence __P((void));
 226 void terminate __P((int status));
 227 void do_file __P((char *chat_file));
 228 int  get_string __P((register char *string));
 229 int  put_string __P((register char *s));
 230 int  write_char __P((int c));
 231 int  put_char __P((int c));
 232 int  get_char __P((void));
 233 void chat_send __P((register char *s));
 234 char *character __P((int c));
 235 void chat_expect __P((register char *s));
 236 char *clean __P((register char *s, int sending));
 237 void break_sequence __P((void));
 238 void terminate __P((int status));
 239 void pack_array __P((char **array, int end));
 240 char *expect_strtok __P((char *, char *));
 241 int vfmtmsg __P((char *, int, const char *, va_list));  /* vsprintf++ */
 242
 243 int main __P((int, char *[]));
 244
 245 void *dup_mem(b, c)
 246 void *b;
 247 size_t c;
 248 {
 249     void *ans = malloc (c);
 250     if (!ans)
 251         fatal(2, "memory error!");
 252
 253     memcpy (ans, b, c);
 254     return ans;
 255 }
 256
 257 void *copy_of (s)
 258 char *s;
 259 {
 260     return dup_mem (s, strlen (s) + 1);
 261 }
 262
 263 /*
 264  * chat [ -v ] [ -E ] [ -T number ] [ -U number ] [ -t timeout ] [ -f chat-file ] \
 265  * [ -r report-file ] \
 266  *              [...[[expect[-say[-expect...]] say expect[-say[-expect]] ...]]]
 267  *
 268  *      Perform a UUCP-dialer-like chat script on stdin and stdout.
 269  */
 270 int
 271 main(argc, argv)
 272      int argc;
 273      char **argv;
 274 {
 275     int option;
 276     char *arg;
 277
 278     program_name = *argv;
 279     tzset();
 280
 281     while ((option = OPTION(argc, argv)) != 0) {
 282         switch (option) {
 283         case 'e':
 284             ++echo;
 285             break;
 286
 287         case 'E':
 288             ++use_env;
 289             break;
 290
 291         case 'v':
 292             ++verbose;
 293             break;
 294
 295         case 'V':
 296             ++Verbose;
 297             break;
 298
 299         case 's':
 300             ++to_stderr;
 301             break;
 302
 303         case 'S':
 304             to_log = 0;
 305             break;
 306
 307         case 'f':
 308             if ((arg = OPTARG(argc, argv)) != NULL)
 309                     chat_file = copy_of(arg);
 310             else
 311                 usage();
 312             break;
 313
 314         case 't':
 315             if ((arg = OPTARG(argc, argv)) != NULL)
 316                 timeout = atoi(arg);
 317             else
 318                 usage();
 319             break;
 320
 321         case 'r':
 322             arg = OPTARG (argc, argv);
 323             if (arg) {
 324                 if (report_fp != NULL)
 325                     fclose (report_fp);
 326                 report_file = copy_of (arg);
 327                 report_fp   = fopen (report_file, "a");
 328                 if (report_fp != NULL) {
 329                     if (verbose)
 330                         fprintf (report_fp, "Opening \"%s\"...\n",
 331                                  report_file);
 332                     report = 1;
 333                 }
 334             }
 335             break;
 336
 337         case 'T':
 338             if ((arg = OPTARG(argc, argv)) != NULL)
 339                 phone_num = copy_of(arg);
 340             else
 341                 usage();
 342             break;
 343
 344         case 'U':
 345             if ((arg = OPTARG(argc, argv)) != NULL)
 346                 phone_num2 = copy_of(arg);
 347             else
 348                 usage();
 349             break;
 350
 351         default:
 352             usage();
 353             break;
 354         }
 355     }
 356 /*
 357  * Default the report file to the stderr location
 358  */
 359     if (report_fp == NULL)
 360         report_fp = stderr;
 361
 362     if (to_log) {
 363 #ifdef ultrix
 364         openlog("chat", LOG_PID);
 365 #else
 366         openlog("chat", LOG_PID | LOG_NDELAY, LOG_LOCAL2);
 367
 368         if (verbose)
 369             setlogmask(LOG_UPTO(LOG_INFO));
 370         else
 371             setlogmask(LOG_UPTO(LOG_WARNING));
 372 #endif
 373     }
 374
 375     init();
 376
 377     if (chat_file != NULL) {
 378         arg = ARG(argc, argv);
 379         if (arg != NULL)
 380             usage();
 381         else
 382             do_file (chat_file);
 383     } else {
 384         while ((arg = ARG(argc, argv)) != NULL) {
 385             chat_expect(arg);
 386
 387             if ((arg = ARG(argc, argv)) != NULL)
 388                 chat_send(arg);
 389         }
 390     }
 391
 392     terminate(0);
 393     return 0;
 394 }
 395
 396 /*
 397  *  Process a chat script when read from a file.
 398  */
 399
 400 void do_file (chat_file)
 401 char *chat_file;
 402 {
 403     int linect, sendflg;
 404     char *sp, *arg, quote;
 405     char buf [STR_LEN];
 406     FILE *cfp;
 407
 408     cfp = fopen (chat_file, "r");
 409     if (cfp == NULL)
 410         fatal(1, "%s -- open failed: %m", chat_file);
 411
 412     linect = 0;
 413     sendflg = 0;
 414
 415     while (fgets(buf, STR_LEN, cfp) != NULL) {
 416         sp = strchr (buf, '\n');
 417         if (sp)
 418             *sp = '\0';
 419
 420         linect++;
 421         sp = buf;
 422
 423         /* lines starting with '#' are comments. If a real '#'
 424            is to be expected, it should be quoted .... */
 425         if ( *sp == '#' )
 426             continue;
 427
 428         while (*sp != '\0') {
 429             if (*sp == ' ' || *sp == '\t') {
 430                 ++sp;
 431                 continue;
 432             }
 433
 434             if (*sp == '"' || *sp == '\'') {
 435                 quote = *sp++;
 436                 arg = sp;
 437                 while (*sp != quote) {
 438                     if (*sp == '\0')
 439                         fatal(1, "unterminated quote (line %d)", linect);
 440
 441                     if (*sp++ == '\\') {
 442                         if (*sp != '\0')
 443                             ++sp;
 444                     }
 445                 }
 446             }
 447             else {
 448                 arg = sp;
 449                 while (*sp != '\0' && *sp != ' ' && *sp != '\t')
 450                     ++sp;
 451             }
 452
 453             if (*sp != '\0')
 454                 *sp++ = '\0';
 455
 456             if (sendflg)
 457                 chat_send (arg);
 458             else
 459                 chat_expect (arg);
 460             sendflg = !sendflg;
 461         }
 462     }
 463     fclose (cfp);
 464 }
 465
 466 /*
 467  *      We got an error parsing the command line.
 468  */
 469 void usage()
 470 {
 471     fprintf(stderr, "\
 472 Usage: %s [-e] [-E] [-v] [-V] [-t timeout] [-r report-file]\n\
 473      [-T phone-number] [-U phone-number2] {-f chat-file | chat-script}\n", program_name);
 474     exit(1);
 475 }
 476
 477 char line[1024];
 478
 479 /*
 480  * Send a message to syslog and/or stderr.
 481  */
 482 void logf __V((const char *fmt, ...))
 483 {
 484     va_list args;
 485
 486 #ifdef __STDC__
 487     va_start(args, fmt);
 488 #else
 489     char *fmt;
 490     va_start(args);
 491     fmt = va_arg(args, char *);
 492 #endif
 493
 494     vfmtmsg(line, sizeof(line), fmt, args);
 495     if (to_log)
 496         syslog(LOG_INFO, "%s", line);
 497     if (to_stderr)
 498         fprintf(stderr, "%s\n", line);
 499 }
 500
 501 /*
 502  *      Print an error message and terminate.
 503  */
 504
 505 void fatal __V((int code, const char *fmt, ...))
 506 {
 507     va_list args;
 508
 509 #ifdef __STDC__
 510     va_start(args, fmt);
 511 #else
 512     int code;
 513     char *fmt;
 514     va_start(args);
 515     code = va_arg(args, int);
 516     fmt = va_arg(args, char *);
 517 #endif
 518
 519     vfmtmsg(line, sizeof(line), fmt, args);
 520     if (to_log)
 521         syslog(LOG_ERR, "%s", line);
 522     if (to_stderr)
 523         fprintf(stderr, "%s\n", line);
 524     terminate(code);
 525 }
 526
 527 int alarmed = 0;
 528
 529 SIGTYPE sigalrm(signo)
 530 int signo;
 531 {
 532     int flags;
 533
 534     alarm(1);
 535     alarmed = 1;                /* Reset alarm to avoid race window */
 536     signal(SIGALRM, sigalrm);   /* that can cause hanging in read() */
 537
 538     if ((flags = fcntl(0, F_GETFL, 0)) == -1)
 539         fatal(2, "Can't get file mode flags on stdin: %m");
 540
 541     if (fcntl(0, F_SETFL, flags | O_NONBLOCK) == -1)
 542         fatal(2, "Can't set file mode flags on stdin: %m");
 543
 544     if (verbose)
 545         logf("alarm");
 546 }
 547
 548 void unalarm()
 549 {
 550     int flags;
 551
 552     if ((flags = fcntl(0, F_GETFL, 0)) == -1)
 553         fatal(2, "Can't get file mode flags on stdin: %m");
 554
 555     if (fcntl(0, F_SETFL, flags & ~O_NONBLOCK) == -1)
 556         fatal(2, "Can't set file mode flags on stdin: %m");
 557 }
 558
 559 SIGTYPE sigint(signo)
 560 int signo;
 561 {
 562     fatal(2, "SIGINT");
 563 }
 564
 565 SIGTYPE sigterm(signo)
 566 int signo;
 567 {
 568     fatal(2, "SIGTERM");
 569 }
 570
 571 SIGTYPE sighup(signo)
 572 int signo;
 573 {
 574     fatal(2, "SIGHUP");
 575 }
 576
 577 void init()
 578 {
 579     signal(SIGINT, sigint);
 580     signal(SIGTERM, sigterm);
 581     signal(SIGHUP, sighup);
 582
 583     set_tty_parameters();
 584     signal(SIGALRM, sigalrm);
 585     alarm(0);
 586     alarmed = 0;
 587 }
 588
 589 void set_tty_parameters()
 590 {
 591 #if defined(get_term_param)
 592     term_parms t;
 593
 594     if (get_term_param (&t) < 0)
 595         fatal(2, "Can't get terminal parameters: %m");
 596
 597     saved_tty_parameters = t;
 598     have_tty_parameters  = 1;
 599
 600     t.c_iflag     |= IGNBRK | ISTRIP | IGNPAR;
 601     t.c_oflag      = 0;
 602     t.c_lflag      = 0;
 603     t.c_cc[VERASE] =
 604     t.c_cc[VKILL]  = 0;
 605     t.c_cc[VMIN]   = 1;
 606     t.c_cc[VTIME]  = 0;
 607
 608     if (set_term_param (&t) < 0)
 609         fatal(2, "Can't set terminal parameters: %m");
 610 #endif
 611 }
 612
 613 void break_sequence()
 614 {
 615 #ifdef TERMIOS
 616     tcsendbreak (0, 0);
 617 #endif
 618 }
 619
 620 void terminate(status)
 621 int status;
 622 {
 623     static int terminating = 0;
 624
 625     if (terminating)
 626         exit(status);
 627     terminating = 1;
 628     echo_stderr(-1);
 629 /*
 630  * Allow the last of the report string to be gathered before we terminate.
 631  */
 632     if (report_gathering) {
 633         int c, rep_len;
 634
 635         rep_len = strlen(report_buffer);
 636         while (rep_len + 1 <= sizeof(report_buffer)) {
 637             alarm(1);
 638             c = get_char();
 639             alarm(0);
 640             if (c < 0 || iscntrl(c))
 641                 break;
 642             report_buffer[rep_len] = c;
 643             ++rep_len;
 644         }
 645         report_buffer[rep_len] = 0;
 646         fprintf (report_fp, "chat:  %s\n", report_buffer);
 647     }
 648     if (report_file != (char *) 0 && report_fp != (FILE *) NULL) {
 649         if (verbose)
 650             fprintf (report_fp, "Closing \"%s\".\n", report_file);
 651         fclose (report_fp);
 652         report_fp = (FILE *) NULL;
 653     }
 654
 655 #if defined(get_term_param)
 656     if (have_tty_parameters) {
 657         if (set_term_param (&saved_tty_parameters) < 0)
 658             fatal(2, "Can't restore terminal parameters: %m");
 659     }
 660 #endif
 661
 662     exit(status);
 663 }
 664
 665 /*
 666  *      'Clean up' this string.
 667  */
 668 char *clean(s, sending)
 669 register char *s;
 670 int sending;  /* set to 1 when sending (putting) this string. */
 671 {
 672     char temp[STR_LEN], env_str[STR_LEN], cur_chr;
 673     register char *s1, *phchar;
 674     int add_return = sending;
 675 #define isoctal(chr)    (((chr) >= '0') && ((chr) <= '7'))
 676 #define isalnumx(chr)   ((((chr) >= '0') && ((chr) <= '9')) \
 677                          || (((chr) >= 'a') && ((chr) <= 'z')) \
 678                          || (((chr) >= 'A') && ((chr) <= 'Z')) \
 679                          || (chr) == '_')
 680
 681     s1 = temp;
 682     while (*s) {
 683         cur_chr = *s++;
 684         if (cur_chr == '^') {
 685             cur_chr = *s++;
 686             if (cur_chr == '\0') {
 687                 *s1++ = '^';
 688                 break;
 689             }
 690             cur_chr &= 0x1F;
 691             if (cur_chr != 0) {
 692                 *s1++ = cur_chr;
 693             }
 694             continue;
 695         }
 696
 697         if (use_env && cur_chr == '$') {                /* ARI */
 698             phchar = env_str;
 699             while (isalnumx(*s))
 700                 *phchar++ = *s++;
 701             *phchar = '\0';
 702             phchar = getenv(env_str);
 703             if (phchar)
 704                 while (*phchar)
 705                     *s1++ = *phchar++;
 706             continue;
 707         }
 708
 709         if (cur_chr != '\\') {
 710             *s1++ = cur_chr;
 711             continue;
 712         }
 713
 714         cur_chr = *s++;
 715         if (cur_chr == '\0') {
 716             if (sending) {
 717                 *s1++ = '\\';
 718                 *s1++ = '\\';
 719             }
 720             break;
 721         }
 722
 723         switch (cur_chr) {
 724         case 'b':
 725             *s1++ = '\b';
 726             break;
 727
 728         case 'c':
 729             if (sending && *s == '\0')
 730                 add_return = 0;
 731             else
 732                 *s1++ = cur_chr;
 733             break;
 734
 735         case '\\':
 736         case 'K':
 737         case 'p':
 738         case 'd':
 739             if (sending)
 740                 *s1++ = '\\';
 741             *s1++ = cur_chr;
 742             break;
 743
 744         case 'T':
 745             if (sending && phone_num) {
 746                 for (phchar = phone_num; *phchar != '\0'; phchar++)
 747                     *s1++ = *phchar;
 748             }
 749             else {
 750                 *s1++ = '\\';
 751                 *s1++ = 'T';
 752             }
 753             break;
 754
 755         case 'U':
 756             if (sending && phone_num2) {
 757                 for (phchar = phone_num2; *phchar != '\0'; phchar++)
 758                     *s1++ = *phchar;
 759             }
 760             else {
 761                 *s1++ = '\\';
 762                 *s1++ = 'U';
 763             }
 764             break;
 765
 766         case 'q':
 767             quiet = 1;
 768             break;
 769
 770         case 'r':
 771             *s1++ = '\r';
 772             break;
 773
 774         case 'n':
 775             *s1++ = '\n';
 776             break;
 777
 778         case 's':
 779             *s1++ = ' ';
 780             break;
 781
 782         case 't':
 783             *s1++ = '\t';
 784             break;
 785
 786         case 'N':
 787             if (sending) {
 788                 *s1++ = '\\';
 789                 *s1++ = '\0';
 790             }
 791             else
 792                 *s1++ = 'N';
 793             break;
 794
 795         case '$':                       /* ARI */
 796             if (use_env) {
 797                 *s1++ = cur_chr;
 798                 break;
 799             }
 800             /* FALL THROUGH */
 801
 802         default:
 803             if (isoctal (cur_chr)) {
 804                 cur_chr &= 0x07;
 805                 if (isoctal (*s)) {
 806                     cur_chr <<= 3;
 807                     cur_chr |= *s++ - '0';
 808                     if (isoctal (*s)) {
 809                         cur_chr <<= 3;
 810                         cur_chr |= *s++ - '0';
 811                     }
 812                 }
 813
 814                 if (cur_chr != 0 || sending) {
 815                     if (sending && (cur_chr == '\\' || cur_chr == 0))
 816                         *s1++ = '\\';
 817                     *s1++ = cur_chr;
 818                 }
 819                 break;
 820             }
 821
 822             if (sending)
 823                 *s1++ = '\\';
 824             *s1++ = cur_chr;
 825             break;
 826         }
 827     }
 828
 829     if (add_return)
 830         *s1++ = '\r';
 831
 832     *s1++ = '\0'; /* guarantee closure */
 833     *s1++ = '\0'; /* terminate the string */
 834     return dup_mem (temp, (size_t) (s1 - temp)); /* may have embedded nuls */
 835 }
 836
 837 /*
 838  * A modified version of 'strtok'. This version skips \ sequences.
 839  */
 840
 841 char *expect_strtok (s, term)
 842      char *s, *term;
 843 {
 844     static  char *str   = "";
 845     int     escape_flag = 0;
 846     char   *result;
 847
 848 /*
 849  * If a string was specified then do initial processing.
 850  */
 851     if (s)
 852         str = s;
 853
 854 /*
 855  * If this is the escape flag then reset it and ignore the character.
 856  */
 857     if (*str)
 858         result = str;
 859     else
 860         result = (char *) 0;
 861
 862     while (*str) {
 863         if (escape_flag) {
 864             escape_flag = 0;
 865             ++str;
 866             continue;
 867         }
 868
 869         if (*str == '\\') {
 870             ++str;
 871             escape_flag = 1;
 872             continue;
 873         }
 874
 875 /*
 876  * If this is not in the termination string, continue.
 877  */
 878         if (strchr (term, *str) == (char *) 0) {
 879             ++str;
 880             continue;
 881         }
 882
 883 /*
 884  * This is the terminator. Mark the end of the string and stop.
 885  */
 886         *str++ = '\0';
 887         break;
 888     }
 889     return (result);
 890 }
 891
 892 /*
 893  * Process the expect string
 894  */
 895
 896 void chat_expect (s)
 897 char *s;
 898 {
 899     char *expect;
 900     char *reply;
 901
 902     if (strcmp(s, "HANGUP") == 0) {
 903         ++hup_next;
 904         return;
 905     }
 906
 907     if (strcmp(s, "ABORT") == 0) {
 908         ++abort_next;
 909         return;
 910     }
 911
 912     if (strcmp(s, "CLR_ABORT") == 0) {
 913         ++clear_abort_next;
 914         return;
 915     }
 916
 917     if (strcmp(s, "REPORT") == 0) {
 918         ++report_next;
 919         return;
 920     }
 921
 922     if (strcmp(s, "CLR_REPORT") == 0) {
 923         ++clear_report_next;
 924         return;
 925     }
 926
 927     if (strcmp(s, "TIMEOUT") == 0) {
 928         ++timeout_next;
 929         return;
 930     }
 931
 932     if (strcmp(s, "ECHO") == 0) {
 933         ++echo_next;
 934         return;
 935     }
 936
 937     if (strcmp(s, "SAY") == 0) {
 938         ++say_next;
 939         return;
 940     }
 941
 942 /*
 943  * Fetch the expect and reply string.
 944  */
 945     for (;;) {
 946         expect = expect_strtok (s, "-");
 947         s      = (char *) 0;
 948
 949         if (expect == (char *) 0)
 950             return;
 951
 952         reply = expect_strtok (s, "-");
 953
 954 /*
 955  * Handle the expect string. If successful then exit.
 956  */
 957         if (get_string (expect))
 958             return;
 959
 960 /*
 961  * If there is a sub-reply string then send it. Otherwise any condition
 962  * is terminal.
 963  */
 964         if (reply == (char *) 0 || exit_code != 3)
 965             break;
 966
 967         chat_send (reply);
 968     }
 969
 970 /*
 971  * The expectation did not occur. This is terminal.
 972  */
 973     if (fail_reason)
 974         logf("Failed (%s)", fail_reason);
 975     else
 976         logf("Failed");
 977     terminate(exit_code);
 978 }
 979
 980 /*
 981  * Translate the input character to the appropriate string for printing
 982  * the data.
 983  */
 984
 985 char *character(c)
 986 int c;
 987 {
 988     static char string[10];
 989     char *meta;
 990
 991     meta = (c & 0x80) ? "M-" : "";
 992     c &= 0x7F;
 993
 994     if (c < 32)
 995         sprintf(string, "%s^%c", meta, (int)c + '@');
 996     else if (c == 127)
 997         sprintf(string, "%s^?", meta);
 998     else
 999         sprintf(string, "%s%c", meta, c);
1000
1001     return (string);
1002 }
1003
1004 /*
1005  *  process the reply string
1006  */
1007 void chat_send (s)
1008 register char *s;
1009 {
1010     char file_data[STR_LEN];
1011
1012     if (say_next) {
1013         say_next = 0;
1014         s = clean(s, 1);
1015         write(2, s, strlen(s));
1016         free(s);
1017         return;
1018     }
1019
1020     if (hup_next) {
1021         hup_next = 0;
1022         if (strcmp(s, "OFF") == 0)
1023            signal(SIGHUP, SIG_IGN);
1024         else
1025            signal(SIGHUP, sighup);
1026         return;
1027     }
1028
1029     if (echo_next) {
1030         echo_next = 0;
1031         echo = (strcmp(s, "ON") == 0);
1032         return;
1033     }
1034
1035     if (abort_next) {
1036         char *s1;
1037
1038         abort_next = 0;
1039
1040         if (n_aborts >= MAX_ABORTS)
1041             fatal(2, "Too many ABORT strings");
1042
1043         s1 = clean(s, 0);
1044
1045         if (strlen(s1) > strlen(s)
1046             || strlen(s1) + 1 > sizeof(fail_buffer))
1047             fatal(1, "Illegal or too-long ABORT string ('%v')", s);
1048
1049         abort_string[n_aborts++] = s1;
1050
1051         if (verbose)
1052             logf("abort on (%v)", s);
1053         return;
1054     }
1055
1056     if (clear_abort_next) {
1057         char *s1;
1058         int   i;
1059         int   old_max;
1060         int   pack = 0;
1061
1062         clear_abort_next = 0;
1063
1064         s1 = clean(s, 0);
1065
1066         if (strlen(s1) > strlen(s)
1067             || strlen(s1) + 1 > sizeof(fail_buffer))
1068             fatal(1, "Illegal or too-long CLR_ABORT string ('%v')", s);
1069
1070         old_max = n_aborts;
1071         for (i=0; i < n_aborts; i++) {
1072             if ( strcmp(s1,abort_string[i]) == 0 ) {
1073                 free(abort_string[i]);
1074                 abort_string[i] = NULL;
1075                 pack++;
1076                 n_aborts--;
1077                 if (verbose)
1078                     logf("clear abort on (%v)", s);
1079             }
1080         }
1081         free(s1);
1082         if (pack)
1083             pack_array(abort_string,old_max);
1084         return;
1085     }
1086
1087     if (report_next) {
1088         char *s1;
1089
1090         report_next = 0;
1091         if (n_reports >= MAX_REPORTS)
1092             fatal(2, "Too many REPORT strings");
1093
1094         s1 = clean(s, 0);
1095
1096         if (strlen(s1) > strlen(s) || strlen(s1) > sizeof fail_buffer - 1)
1097             fatal(1, "Illegal or too-long REPORT string ('%v')", s);
1098
1099         report_string[n_reports++] = s1;
1100
1101         if (verbose)
1102             logf("report (%v)", s);
1103         return;
1104     }
1105
1106     if (clear_report_next) {
1107         char *s1;
1108         int   i;
1109         int   old_max;
1110         int   pack = 0;
1111
1112         clear_report_next = 0;
1113
1114         s1 = clean(s, 0);
1115
1116         if (strlen(s1) > strlen(s) || strlen(s1) > sizeof fail_buffer - 1)
1117             fatal(1, "Illegal or too-long REPORT string ('%v')", s);
1118
1119         old_max = n_reports;
1120         for (i=0; i < n_reports; i++) {
1121             if ( strcmp(s1,report_string[i]) == 0 ) {
1122                 free(report_string[i]);
1123                 report_string[i] = NULL;
1124                 pack++;
1125                 n_reports--;
1126                 if (verbose)
1127                     logf("clear report (%v)", s);
1128             }
1129         }
1130         free(s1);
1131         if (pack)
1132             pack_array(report_string,old_max);
1133
1134         return;
1135     }
1136
1137     if (timeout_next) {
1138         timeout_next = 0;
1139         timeout = atoi(s);
1140
1141         if (timeout <= 0)
1142             timeout = DEFAULT_CHAT_TIMEOUT;
1143
1144         if (verbose)
1145             logf("timeout set to %d seconds", timeout);
1146
1147         return;
1148     }
1149
1150     /*
1151      * The syntax @filename means read the string to send from the
1152      * file `filename'.
1153      */
1154     if (s[0] == '@') {
1155         /* skip the @ and any following white-space */
1156         char *fn = s;
1157         while (*++fn == ' ' || *fn == '\t')
1158             ;
1159
1160         if (*fn != 0) {
1161             FILE *f;
1162             int n = 0;
1163
1164             /* open the file and read until STR_LEN-1 bytes or end-of-file */
1165             f = fopen(fn, "r");
1166             if (f == NULL)
1167                 fatal(1, "%s -- open failed: %m", fn);
1168             while (n < STR_LEN - 1) {
1169                 int nr = fread(&file_data[n], 1, STR_LEN - 1 - n, f);
1170                 if (nr < 0)
1171                     fatal(1, "%s -- read error", fn);
1172                 if (nr == 0)
1173                     break;
1174                 n += nr;
1175             }
1176             fclose(f);
1177
1178             /* use the string we got as the string to send,
1179                but trim off the final newline if any. */
1180             if (n > 0 && file_data[n-1] == '\n')
1181                 --n;
1182             file_data[n] = 0;
1183             s = file_data;
1184         }
1185     }
1186
1187     if (strcmp(s, "EOT") == 0)
1188         s = "^D\\c";
1189     else if (strcmp(s, "BREAK") == 0)
1190         s = "\\K\\c";
1191
1192     if (!put_string(s))
1193         fatal(1, "Failed");
1194 }
1195
1196 int get_char()
1197 {
1198     int status;
1199     char c;
1200
1201     status = read(0, &c, 1);
1202
1203     switch (status) {
1204     case 1:
1205         return ((int)c & 0x7F);
1206
1207     default:
1208         logf("warning: read() on stdin returned %d", status);
1209
1210     case -1:
1211         if ((status = fcntl(0, F_GETFL, 0)) == -1)
1212             fatal(2, "Can't get file mode flags on stdin: %m");
1213
1214         if (fcntl(0, F_SETFL, status & ~O_NONBLOCK) == -1)
1215             fatal(2, "Can't set file mode flags on stdin: %m");
1216
1217         return (-1);
1218     }
1219 }
1220
1221 int put_char(c)
1222 int c;
1223 {
1224     int status;
1225     char ch = c;
1226
1227     usleep(10000);              /* inter-character typing delay (?) */
1228
1229     status = write(1, &ch, 1);
1230
1231     switch (status) {
1232     case 1:
1233         return (0);
1234
1235     default:
1236         logf("warning: write() on stdout returned %d", status);
1237
1238     case -1:
1239         if ((status = fcntl(0, F_GETFL, 0)) == -1)
1240             fatal(2, "Can't get file mode flags on stdin, %m");
1241
1242         if (fcntl(0, F_SETFL, status & ~O_NONBLOCK) == -1)
1243             fatal(2, "Can't set file mode flags on stdin: %m");
1244
1245         return (-1);
1246     }
1247 }
1248
1249 int write_char (c)
1250 int c;
1251 {
1252     if (alarmed || put_char(c) < 0) {
1253         alarm(0);
1254         alarmed = 0;
1255
1256         if (verbose) {
1257             if (errno == EINTR || errno == EWOULDBLOCK)
1258                 logf(" -- write timed out");
1259             else
1260                 logf(" -- write failed: %m");
1261         }
1262         return (0);
1263     }
1264     return (1);
1265 }
1266
1267 int put_string (s)
1268 register char *s;
1269 {
1270     quiet = 0;
1271     s = clean(s, 1);
1272
1273     if (verbose) {
1274         if (quiet)
1275             logf("send (??????)");
1276         else
1277             logf("send (%v)", s);
1278     }
1279
1280     alarm(timeout); alarmed = 0;
1281
1282     while (*s) {
1283         register char c = *s++;
1284
1285         if (c != '\\') {
1286             if (!write_char (c))
1287                 return 0;
1288             continue;
1289         }
1290
1291         c = *s++;
1292         switch (c) {
1293         case 'd':
1294             sleep(1);
1295             break;
1296
1297         case 'K':
1298             break_sequence();
1299             break;
1300
1301         case 'p':
1302             usleep(10000);      /* 1/100th of a second (arg is microseconds) */
1303             break;
1304
1305         default:
1306             if (!write_char (c))
1307                 return 0;
1308             break;
1309         }
1310     }
1311
1312     alarm(0);
1313     alarmed = 0;
1314     return (1);
1315 }
1316
1317 /*
1318  *      Echo a character to stderr.
1319  *      When called with -1, a '\n' character is generated when
1320  *      the cursor is not at the beginning of a line.
1321  */
1322 void echo_stderr(n)
1323 int n;
1324 {
1325     static int need_lf;
1326     char *s;
1327
1328     switch (n) {
1329     case '\r':          /* ignore '\r' */
1330         break;
1331     case -1:
1332         if (need_lf == 0)
1333             break;
1334         /* fall through */
1335     case '\n':
1336         write(2, "\n", 1);
1337         need_lf = 0;
1338         break;
1339     default:
1340         s = character(n);
1341         write(2, s, strlen(s));
1342         need_lf = 1;
1343         break;
1344     }
1345 }
1346
1347 /*
1348  *      'Wait for' this string to appear on this file descriptor.
1349  */
1350 int get_string(string)
1351 register char *string;
1352 {
1353     char temp[STR_LEN];
1354     int c, printed = 0, len, minlen;
1355     register char *s = temp, *end = s + STR_LEN;
1356     char *logged = temp;
1357
1358     fail_reason = (char *)0;
1359     string = clean(string, 0);
1360     len = strlen(string);
1361     minlen = (len > sizeof(fail_buffer)? len: sizeof(fail_buffer)) - 1;
1362
1363     if (verbose)
1364         logf("expect (%v)", string);
1365
1366     if (len > STR_LEN) {
1367         logf("expect string is too long");
1368         exit_code = 1;
1369         return 0;
1370     }
1371
1372     if (len == 0) {
1373         if (verbose)
1374             logf("got it");
1375         return (1);
1376     }
1377
1378     alarm(timeout);
1379     alarmed = 0;
1380
1381     while ( ! alarmed && (c = get_char()) >= 0) {
1382         int n, abort_len, report_len;
1383
1384         if (echo)
1385             echo_stderr(c);
1386         if (verbose && c == '\n') {
1387             if (s == logged)
1388                 logf("");       /* blank line */
1389             else
1390                 logf("%0.*v", s - logged, logged);
1391             logged = s + 1;
1392         }
1393
1394         *s++ = c;
1395
1396         if (verbose && s >= logged + 80) {
1397             logf("%0.*v", s - logged, logged);
1398             logged = s;
1399         }
1400
1401         if (Verbose) {
1402            if (c == '\n')
1403                fputc( '\n', stderr );
1404            else if (c != '\r')
1405                fprintf( stderr, "%s", character(c) );
1406         }
1407
1408         if (!report_gathering) {
1409             for (n = 0; n < n_reports; ++n) {
1410                 if ((report_string[n] != (char*) NULL) &&
1411                     s - temp >= (report_len = strlen(report_string[n])) &&
1412                     strncmp(s - report_len, report_string[n], report_len) == 0) {
1413                     time_t time_now   = time ((time_t*) NULL);
1414                     struct tm* tm_now = localtime (&time_now);
1415
1416                     strftime (report_buffer, 20, "%b %d %H:%M:%S ", tm_now);
1417                     strcat (report_buffer, report_string[n]);
1418
1419                     report_string[n] = (char *) NULL;
1420                     report_gathering = 1;
1421                     break;
1422                 }
1423             }
1424         }
1425         else {
1426             if (!iscntrl (c)) {
1427                 int rep_len = strlen (report_buffer);
1428                 report_buffer[rep_len]     = c;
1429                 report_buffer[rep_len + 1] = '\0';
1430             }
1431             else {
1432                 report_gathering = 0;
1433                 fprintf (report_fp, "chat:  %s\n", report_buffer);
1434             }
1435         }
1436
1437         if (s - temp >= len &&
1438             c == string[len - 1] &&
1439             strncmp(s - len, string, len) == 0) {
1440             if (verbose) {
1441                 if (s > logged)
1442                     logf("%0.*v", s - logged, logged);
1443                 logf(" -- got it\n");
1444             }
1445
1446             alarm(0);
1447             alarmed = 0;
1448             return (1);
1449         }
1450
1451         for (n = 0; n < n_aborts; ++n) {
1452             if (s - temp >= (abort_len = strlen(abort_string[n])) &&
1453                 strncmp(s - abort_len, abort_string[n], abort_len) == 0) {
1454                 if (verbose) {
1455                     if (s > logged)
1456                         logf("%0.*v", s - logged, logged);
1457                     logf(" -- failed");
1458                 }
1459
1460                 alarm(0);
1461                 alarmed = 0;
1462                 exit_code = n + 4;
1463                 strcpy(fail_reason = fail_buffer, abort_string[n]);
1464                 return (0);
1465             }
1466         }
1467
1468         if (s >= end) {
1469             if (logged < s - minlen) {
1470                 if (verbose)
1471                     logf("%0.*v", s - logged, logged);
1472                 logged = s;
1473             }
1474             s -= minlen;
1475             memmove(temp, s, minlen);
1476             logged = temp + (logged - s);
1477             s = temp + minlen;
1478         }
1479
1480         if (alarmed && verbose)
1481             logf("warning: alarm synchronization problem");
1482     }
1483
1484     alarm(0);
1485
1486     if (verbose && printed) {
1487         if (alarmed)
1488             logf(" -- read timed out");
1489         else
1490             logf(" -- read failed: %m");
1491     }
1492
1493     exit_code = 3;
1494     alarmed   = 0;
1495     return (0);
1496 }
1497
1498 /*
1499  * Gross kludge to handle Solaris versions >= 2.6 having usleep.
1500  */
1501 #ifdef SOL2
1502 #include <sys/param.h>
1503 #if MAXUID > 65536                  /* then this is Solaris 2.6 or later */
1504 #undef NO_USLEEP
1505 #endif
1506 #endif /* SOL2 */
1507
1508 #ifdef NO_USLEEP
1509 #include <sys/types.h>
1510 #include <sys/time.h>
1511
1512 /*
1513   usleep -- support routine for 4.2BSD system call emulations
1514   last edit:  29-Oct-1984     D A Gwyn
1515   */
1516
1517 extern int        select();
1518
1519 int
1520 usleep( usec )                            /* returns 0 if ok, else -1 */
1521     long                usec;           /* delay in microseconds */
1522 {
1523     static struct {             /* `timeval' */
1524         long    tv_sec;         /* seconds */
1525         long    tv_usec;        /* microsecs */
1526     } delay;                    /* _select() timeout */
1527
1528     delay.tv_sec  = usec / 1000000L;
1529     delay.tv_usec = usec % 1000000L;
1530
1531     return select(0, (long *)0, (long *)0, (long *)0, &delay);
1532 }
1533 #endif
1534
1535 void
1536 pack_array (array, end)
1537     char **array; /* The address of the array of string pointers */
1538     int    end;   /* The index of the next free entry before CLR_ */
1539 {
1540     int i, j;
1541
1542     for (i = 0; i < end; i++) {
1543         if (array[i] == NULL) {
1544             for (j = i+1; j < end; ++j)
1545                 if (array[j] != NULL)
1546                     array[i++] = array[j];
1547             for (; i < end; ++i)
1548                 array[i] = NULL;
1549             break;
1550         }
1551     }
1552 }
1553
1554 /*
1555  * vfmtmsg - format a message into a buffer.  Like vsprintf except we
1556  * also specify the length of the output buffer, and we handle the
1557  * %m (error message) format.
1558  * Doesn't do floating-point formats.
1559  * Returns the number of chars put into buf.
1560  */
1561 #define OUTCHAR(c)      (buflen > 0? (--buflen, *buf++ = (c)): 0)
1562
1563 int
1564 vfmtmsg(buf, buflen, fmt, args)
1565     char *buf;
1566     int buflen;
1567     const char *fmt;
1568     va_list args;
1569 {
1570     int c, i, n;
1571     int width, prec, fillch;
1572     int base, len, neg, quoted;
1573     unsigned long val = 0;
1574     char *str, *buf0;
1575     const char *f;
1576     unsigned char *p;
1577     char num[32];
1578     static char hexchars[] = "0123456789abcdef";
1579
1580     buf0 = buf;
1581     --buflen;
1582     while (buflen > 0) {
1583         for (f = fmt; *f != '%' && *f != 0; ++f)
1584             ;
1585         if (f > fmt) {
1586             len = f - fmt;
1587             if (len > buflen)
1588                 len = buflen;
1589             memcpy(buf, fmt, len);
1590             buf += len;
1591             buflen -= len;
1592             fmt = f;
1593         }
1594         if (*fmt == 0)
1595             break;
1596         c = *++fmt;
1597         width = prec = 0;
1598         fillch = ' ';
1599         if (c == '0') {
1600             fillch = '0';
1601             c = *++fmt;
1602         }
1603         if (c == '*') {
1604             width = va_arg(args, int);
1605             c = *++fmt;
1606         } else {
1607             while (isdigit(c)) {
1608                 width = width * 10 + c - '0';
1609                 c = *++fmt;
1610             }
1611         }
1612         if (c == '.') {
1613             c = *++fmt;
1614             if (c == '*') {
1615                 prec = va_arg(args, int);
1616                 c = *++fmt;
1617             } else {
1618                 while (isdigit(c)) {
1619                     prec = prec * 10 + c - '0';
1620                     c = *++fmt;
1621                 }
1622             }
1623         }
1624         str = 0;
1625         base = 0;
1626         neg = 0;
1627         ++fmt;
1628         switch (c) {
1629         case 'd':
1630             i = va_arg(args, int);
1631             if (i < 0) {
1632                 neg = 1;
1633                 val = -i;
1634             } else
1635                 val = i;
1636             base = 10;
1637             break;
1638         case 'o':
1639             val = va_arg(args, unsigned int);
1640             base = 8;
1641             break;
1642         case 'x':
1643             val = va_arg(args, unsigned int);
1644             base = 16;
1645             break;
1646         case 'p':
1647             val = (unsigned long) va_arg(args, void *);
1648             base = 16;
1649             neg = 2;
1650             break;
1651         case 's':
1652             str = va_arg(args, char *);
1653             break;
1654         case 'c':
1655             num[0] = va_arg(args, int);
1656             num[1] = 0;
1657             str = num;
1658             break;
1659         case 'm':
1660             str = strerror(errno);
1661             break;
1662         case 'v':               /* "visible" string */
1663         case 'q':               /* quoted string */
1664             quoted = c == 'q';
1665             p = va_arg(args, unsigned char *);
1666             if (fillch == '0' && prec > 0) {
1667                 n = prec;
1668             } else {
1669                 n = strlen((char *)p);
1670                 if (prec > 0 && prec < n)
1671                     n = prec;
1672             }
1673             while (n > 0 && buflen > 0) {
1674                 c = *p++;
1675                 --n;
1676                 if (!quoted && c >= 0x80) {
1677                     OUTCHAR('M');
1678                     OUTCHAR('-');
1679                     c -= 0x80;
1680                 }
1681                 if (quoted && (c == '"' || c == '\\'))
1682                     OUTCHAR('\\');
1683                 if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
1684                     if (quoted) {
1685                         OUTCHAR('\\');
1686                         switch (c) {
1687                         case '\t':      OUTCHAR('t');   break;
1688                         case '\n':      OUTCHAR('n');   break;
1689                         case '\b':      OUTCHAR('b');   break;
1690                         case '\f':      OUTCHAR('f');   break;
1691                         default:
1692                             OUTCHAR('x');
1693                             OUTCHAR(hexchars[c >> 4]);
1694                             OUTCHAR(hexchars[c & 0xf]);
1695                         }
1696                     } else {
1697                         if (c == '\t')
1698                             OUTCHAR(c);
1699                         else {
1700                             OUTCHAR('^');
1701                             OUTCHAR(c ^ 0x40);
1702                         }
1703                     }
1704                 } else
1705                     OUTCHAR(c);
1706             }
1707             continue;
1708         default:
1709             *buf++ = '%';
1710             if (c != '%')
1711                 --fmt;          /* so %z outputs %z etc. */
1712             --buflen;
1713             continue;
1714         }
1715         if (base != 0) {
1716             str = num + sizeof(num);
1717             *--str = 0;
1718             while (str > num + neg) {
1719                 *--str = hexchars[val % base];
1720                 val = val / base;
1721                 if (--prec <= 0 && val == 0)
1722                     break;
1723             }
1724             switch (neg) {
1725             case 1:
1726                 *--str = '-';
1727                 break;
1728             case 2:
1729                 *--str = 'x';
1730                 *--str = '0';
1731                 break;
1732             }
1733             len = num + sizeof(num) - 1 - str;
1734         } else {
1735             len = strlen(str);
1736             if (prec > 0 && len > prec)
1737                 len = prec;
1738         }
1739         if (width > 0) {
1740             if (width > buflen)
1741                 width = buflen;
1742             if ((n = width - len) > 0) {
1743                 buflen -= n;
1744                 for (; n > 0; --n)
1745                     *buf++ = fillch;
1746             }
1747         }
1748         if (len > buflen)
1749             len = buflen;
1750         memcpy(buf, str, len);
1751         buf += len;
1752         buflen -= len;
1753     }
1754     *buf = 0;
1755     return buf - buf0;
1756 }