1 /*
2  * Copyright 2000 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 /*
6  *	Chat -- a program for automatic session establishment (i.e. dial
7  *		the phone and log in).
8  *
9  * Standard termination codes:
10  *  0 - successful completion of the script
11  *  1 - invalid argument, expect string too large, etc.
12  *  2 - error on an I/O operation or fatal error condition.
13  *  3 - timeout waiting for a simple string.
14  *  4 - the first string declared as "ABORT"
15  *  5 - the second string declared as "ABORT"
16  *  6 - ... and so on for successive ABORT strings.
17  *
18  *	This software is in the public domain.
19  *
20  * -----------------
21  *	22-May-99 added environment substitutuion, enabled with -E switch.
22  *	Andreas Arens <andras@cityweb.de>.
23  *
24  *	12-May-99 added a feature to read data to be sent from a file,
25  *	if the send string starts with @.  Idea from gpk <gpk@onramp.net>.
26  *
27  *	added -T and -U option and \T and \U substitution to pass a phone
28  *	number into chat script. Two are needed for some ISDN TA applications.
29  *	Keith Dart <kdart@cisco.com>
30  *
31  *
32  *	Added SAY keyword to send output to stderr.
33  *      This allows to turn ECHO OFF and to output specific, user selected,
34  *      text to give progress messages. This best works when stderr
35  *      exists (i.e.: pppd in nodetach mode).
36  *
37  * 	Added HANGUP directives to allow for us to be called
38  *      back. When HANGUP is set to NO, chat will not hangup at HUP signal.
39  *      We rely on timeouts in that case.
40  *
41  *      Added CLR_ABORT to clear previously set ABORT string. This has been
42  *      dictated by the HANGUP above as "NO CARRIER" (for example) must be
43  *      an ABORT condition until we know the other host is going to close
44  *      the connection for call back. As soon as we have completed the
45  *      first stage of the call back sequence, "NO CARRIER" is a valid, non
46  *      fatal string. As soon as we got called back (probably get "CONNECT"),
47  *      we should re-arm the ABORT "NO CARRIER". Hence the CLR_ABORT command.
48  *      Note that CLR_ABORT packs the abort_strings[] array so that we do not
49  *      have unused entries not being reclaimed.
50  *
51  *      In the same vein as above, added CLR_REPORT keyword.
52  *
53  *      Allow for comments. Line starting with '#' are comments and are
54  *      ignored. If a '#' is to be expected as the first character, the
55  *      expect string must be quoted.
56  *
57  *
58  *		Francis Demierre <Francis@SwissMail.Com>
59  * 		Thu May 15 17:15:40 MET DST 1997
60  *
61  *
62  *      Added -r "report file" switch & REPORT keyword.
63  *              Robert Geer <bgeer@xmission.com>
64  *
65  *      Added -s "use stderr" and -S "don't use syslog" switches.
66  *              June 18, 1997
67  *              Karl O. Pinc <kop@meme.com>
68  *
69  *
70  *	Added -e "echo" switch & ECHO keyword
71  *		Dick Streefland <dicks@tasking.nl>
72  *
73  *
74  *	Considerable updates and modifications by
75  *		Al Longyear <longyear@pobox.com>
76  *		Paul Mackerras <paulus@cs.anu.edu.au>
77  *
78  *
79  *	The original author is:
80  *
81  *		Karl Fox <karl@MorningStar.Com>
82  *		Morning Star Technologies, Inc.
83  *		1760 Zollinger Road
84  *		Columbus, OH  43221
85  *		(614)451-1883
86  *
87  */
88 
89 #ifndef __STDC__
90 #define const
91 #endif
92 
93 #pragma ident	"%Z%%M%	%I%	%E% SMI"
94 
95 #ifndef lint
96 static const char rcsid[] = "$Id: chat.c,v 1.26 1999/12/23 01:39:54 paulus Exp $";
97 #endif
98 
99 #include <stdio.h>
100 #include <ctype.h>
101 #include <time.h>
102 #include <fcntl.h>
103 #include <signal.h>
104 #include <errno.h>
105 #include <string.h>
106 #include <stdlib.h>
107 #include <unistd.h>
108 #include <sys/types.h>
109 #include <sys/stat.h>
110 #include <syslog.h>
111 
112 #ifndef TERMIO
113 #undef	TERMIOS
114 #define TERMIOS
115 #endif
116 
117 #ifdef TERMIO
118 #include <termio.h>
119 #endif
120 #ifdef TERMIOS
121 #include <termios.h>
122 #endif
123 
124 #define	STR_LEN	1024
125 
126 #ifndef SIGTYPE
127 #define SIGTYPE void
128 #endif
129 
130 #undef __P
131 #undef __V
132 
133 #ifdef __STDC__
134 #include <stdarg.h>
135 #define __V(x)	x
136 #define __P(x)	x
137 #else
138 #include <varargs.h>
139 #define __V(x)	(va_alist) va_dcl
140 #define __P(x)	()
141 #define const
142 #endif
143 
144 #ifndef O_NONBLOCK
145 #define O_NONBLOCK	O_NDELAY
146 #endif
147 
148 #ifdef SUNOS
149 extern int sys_nerr;
150 extern char *sys_errlist[];
151 #define memmove(to, from, n)	bcopy(from, to, n)
152 #define strerror(n)		((unsigned)(n) < sys_nerr? sys_errlist[(n)] :\
153 				 "unknown error")
154 #endif
155 
156 /*************** Micro getopt() *********************************************/
157 #define	OPTION(c,v)	(_O&2&&**v?*(*v)++:!c||_O&4?0:(!(_O&1)&& \
158 				(--c,++v),_O=4,c&&**v=='-'&&v[0][1]?*++*v=='-'\
159 				&&!v[0][1]?(--c,++v,0):(_O=2,*(*v)++):0))
160 #define	OPTARG(c,v)	(_O&2?**v||(++v,--c)?(_O=1,--c,*v++): \
161 				(_O=4,(char*)0):(char*)0)
162 #define	OPTONLYARG(c,v)	(_O&2&&**v?(_O=1,--c,*v++):(char*)0)
163 #define	ARG(c,v)	(c?(--c,*v++):(char*)0)
164 
165 static int _O = 0;		/* Internal state */
166 /*************** Micro getopt() *********************************************/
167 
168 char *program_name;
169 
170 #define	MAX_ABORTS		50
171 #define	MAX_REPORTS		50
172 #define	DEFAULT_CHAT_TIMEOUT	45
173 
174 int echo          = 0;
175 int verbose       = 0;
176 int to_log        = 1;
177 int to_stderr     = 0;
178 int Verbose       = 0;
179 int quiet         = 0;
180 int report        = 0;
181 int use_env       = 0;
182 int exit_code     = 0;
183 FILE* report_fp   = (FILE *) 0;
184 char *report_file = (char *) 0;
185 char *chat_file   = (char *) 0;
186 char *phone_num   = (char *) 0;
187 char *phone_num2  = (char *) 0;
188 int timeout       = DEFAULT_CHAT_TIMEOUT;
189 
190 int have_tty_parameters = 0;
191 
192 #ifdef TERMIO
193 #define term_parms struct termio
194 #define get_term_param(param) ioctl(0, TCGETA, param)
195 #define set_term_param(param) ioctl(0, TCSETA, param)
196 struct termio saved_tty_parameters;
197 #endif
198 
199 #ifdef TERMIOS
200 #define term_parms struct termios
201 #define get_term_param(param) tcgetattr(0, param)
202 #define set_term_param(param) tcsetattr(0, TCSANOW, param)
203 struct termios saved_tty_parameters;
204 #endif
205 
206 char *abort_string[MAX_ABORTS], *fail_reason = (char *)0,
207 	fail_buffer[50];
208 int n_aborts = 0, abort_next = 0, timeout_next = 0, echo_next = 0;
209 int clear_abort_next = 0;
210 
211 char *report_string[MAX_REPORTS] ;
212 char  report_buffer[50] ;
213 int n_reports = 0, report_next = 0, report_gathering = 0 ;
214 int clear_report_next = 0;
215 
216 int say_next = 0, hup_next = 0;
217 
218 void *dup_mem __P((void *b, size_t c));
219 void *copy_of __P((char *s));
220 void usage __P((void));
221 void logf __P((const char *fmt, ...));
222 void fatal __P((int code, const char *fmt, ...));
223 SIGTYPE sigalrm __P((int signo));
224 SIGTYPE sigint __P((int signo));
225 SIGTYPE sigterm __P((int signo));
226 SIGTYPE sighup __P((int signo));
227 void unalarm __P((void));
228 void init __P((void));
229 void set_tty_parameters __P((void));
230 void echo_stderr __P((int));
231 void break_sequence __P((void));
232 void terminate __P((int status));
233 void do_file __P((char *chat_file));
234 int  get_string __P((register char *string));
235 int  put_string __P((register char *s));
236 int  write_char __P((int c));
237 int  put_char __P((int c));
238 int  get_char __P((void));
239 void chat_send __P((register char *s));
240 char *character __P((int c));
241 void chat_expect __P((register char *s));
242 char *clean __P((register char *s, int sending));
243 void break_sequence __P((void));
244 void terminate __P((int status));
245 void pack_array __P((char **array, int end));
246 char *expect_strtok __P((char *, char *));
247 int vfmtmsg __P((char *, int, const char *, va_list));	/* vsprintf++ */
248 
249 int main __P((int, char *[]));
250 
251 void *dup_mem(b, c)
252 void *b;
253 size_t c;
254 {
255     void *ans = malloc (c);
256     if (!ans)
257 	fatal(2, "memory error!");
258 
259     memcpy (ans, b, c);
260     return ans;
261 }
262 
263 void *copy_of (s)
264 char *s;
265 {
266     return dup_mem (s, strlen (s) + 1);
267 }
268 
269 /*
270  * chat [ -v ] [ -E ] [ -T number ] [ -U number ] [ -t timeout ] [ -f chat-file ] \
271  * [ -r report-file ] \
272  *		[...[[expect[-say[-expect...]] say expect[-say[-expect]] ...]]]
273  *
274  *	Perform a UUCP-dialer-like chat script on stdin and stdout.
275  */
276 int
277 main(argc, argv)
278      int argc;
279      char **argv;
280 {
281     int option;
282     char *arg;
283 
284     program_name = *argv;
285     tzset();
286 
287     while ((option = OPTION(argc, argv)) != 0) {
288 	switch (option) {
289 	case 'e':
290 	    ++echo;
291 	    break;
292 
293 	case 'E':
294 	    ++use_env;
295 	    break;
296 
297 	case 'v':
298 	    ++verbose;
299 	    break;
300 
301 	case 'V':
302 	    ++Verbose;
303 	    break;
304 
305 	case 's':
306 	    ++to_stderr;
307 	    break;
308 
309 	case 'S':
310 	    to_log = 0;
311 	    break;
312 
313 	case 'f':
314 	    if ((arg = OPTARG(argc, argv)) != NULL)
315 		    chat_file = copy_of(arg);
316 	    else
317 		usage();
318 	    break;
319 
320 	case 't':
321 	    if ((arg = OPTARG(argc, argv)) != NULL)
322 		timeout = atoi(arg);
323 	    else
324 		usage();
325 	    break;
326 
327 	case 'r':
328 	    arg = OPTARG (argc, argv);
329 	    if (arg) {
330 		if (report_fp != NULL)
331 		    fclose (report_fp);
332 		report_file = copy_of (arg);
333 		report_fp   = fopen (report_file, "a");
334 		if (report_fp != NULL) {
335 		    if (verbose)
336 			fprintf (report_fp, "Opening \"%s\"...\n",
337 				 report_file);
338 		    report = 1;
339 		}
340 	    }
341 	    break;
342 
343 	case 'T':
344 	    if ((arg = OPTARG(argc, argv)) != NULL)
345 		phone_num = copy_of(arg);
346 	    else
347 		usage();
348 	    break;
349 
350 	case 'U':
351 	    if ((arg = OPTARG(argc, argv)) != NULL)
352 		phone_num2 = copy_of(arg);
353 	    else
354 		usage();
355 	    break;
356 
357 	default:
358 	    usage();
359 	    break;
360 	}
361     }
362 /*
363  * Default the report file to the stderr location
364  */
365     if (report_fp == NULL)
366 	report_fp = stderr;
367 
368     if (to_log) {
369 #ifdef ultrix
370 	openlog("chat", LOG_PID);
371 #else
372 	openlog("chat", LOG_PID | LOG_NDELAY, LOG_LOCAL2);
373 
374 	if (verbose)
375 	    setlogmask(LOG_UPTO(LOG_INFO));
376 	else
377 	    setlogmask(LOG_UPTO(LOG_WARNING));
378 #endif
379     }
380 
381     init();
382 
383     if (chat_file != NULL) {
384 	arg = ARG(argc, argv);
385 	if (arg != NULL)
386 	    usage();
387 	else
388 	    do_file (chat_file);
389     } else {
390 	while ((arg = ARG(argc, argv)) != NULL) {
391 	    chat_expect(arg);
392 
393 	    if ((arg = ARG(argc, argv)) != NULL)
394 		chat_send(arg);
395 	}
396     }
397 
398     terminate(0);
399     return 0;
400 }
401 
402 /*
403  *  Process a chat script when read from a file.
404  */
405 
406 void do_file (chat_file)
407 char *chat_file;
408 {
409     int linect, sendflg;
410     char *sp, *arg, quote;
411     char buf [STR_LEN];
412     FILE *cfp;
413 
414     cfp = fopen (chat_file, "r");
415     if (cfp == NULL)
416 	fatal(1, "%s -- open failed: %m", chat_file);
417 
418     linect = 0;
419     sendflg = 0;
420 
421     while (fgets(buf, STR_LEN, cfp) != NULL) {
422 	sp = strchr (buf, '\n');
423 	if (sp)
424 	    *sp = '\0';
425 
426 	linect++;
427 	sp = buf;
428 
429         /* lines starting with '#' are comments. If a real '#'
430            is to be expected, it should be quoted .... */
431         if ( *sp == '#' )
432 	    continue;
433 
434 	while (*sp != '\0') {
435 	    if (*sp == ' ' || *sp == '\t') {
436 		++sp;
437 		continue;
438 	    }
439 
440 	    if (*sp == '"' || *sp == '\'') {
441 		quote = *sp++;
442 		arg = sp;
443 		while (*sp != quote) {
444 		    if (*sp == '\0')
445 			fatal(1, "unterminated quote (line %d)", linect);
446 
447 		    if (*sp++ == '\\') {
448 			if (*sp != '\0')
449 			    ++sp;
450 		    }
451 		}
452 	    }
453 	    else {
454 		arg = sp;
455 		while (*sp != '\0' && *sp != ' ' && *sp != '\t')
456 		    ++sp;
457 	    }
458 
459 	    if (*sp != '\0')
460 		*sp++ = '\0';
461 
462 	    if (sendflg)
463 		chat_send (arg);
464 	    else
465 		chat_expect (arg);
466 	    sendflg = !sendflg;
467 	}
468     }
469     fclose (cfp);
470 }
471 
472 /*
473  *	We got an error parsing the command line.
474  */
475 void usage()
476 {
477     fprintf(stderr, "\
478 Usage: %s [-e] [-E] [-v] [-V] [-t timeout] [-r report-file]\n\
479      [-T phone-number] [-U phone-number2] {-f chat-file | chat-script}\n", program_name);
480     exit(1);
481 }
482 
483 char line[1024];
484 
485 /*
486  * Send a message to syslog and/or stderr.
487  */
488 void logf __V((const char *fmt, ...))
489 {
490     va_list args;
491 
492 #ifdef __STDC__
493     va_start(args, fmt);
494 #else
495     char *fmt;
496     va_start(args);
497     fmt = va_arg(args, char *);
498 #endif
499 
500     vfmtmsg(line, sizeof(line), fmt, args);
501     if (to_log)
502 	syslog(LOG_INFO, "%s", line);
503     if (to_stderr)
504 	fprintf(stderr, "%s\n", line);
505 }
506 
507 /*
508  *	Print an error message and terminate.
509  */
510 
511 void fatal __V((int code, const char *fmt, ...))
512 {
513     va_list args;
514 
515 #ifdef __STDC__
516     va_start(args, fmt);
517 #else
518     int code;
519     char *fmt;
520     va_start(args);
521     code = va_arg(args, int);
522     fmt = va_arg(args, char *);
523 #endif
524 
525     vfmtmsg(line, sizeof(line), fmt, args);
526     if (to_log)
527 	syslog(LOG_ERR, "%s", line);
528     if (to_stderr)
529 	fprintf(stderr, "%s\n", line);
530     terminate(code);
531 }
532 
533 int alarmed = 0;
534 
535 SIGTYPE sigalrm(signo)
536 int signo;
537 {
538     int flags;
539 
540     alarm(1);
541     alarmed = 1;		/* Reset alarm to avoid race window */
542     signal(SIGALRM, sigalrm);	/* that can cause hanging in read() */
543 
544     if ((flags = fcntl(0, F_GETFL, 0)) == -1)
545 	fatal(2, "Can't get file mode flags on stdin: %m");
546 
547     if (fcntl(0, F_SETFL, flags | O_NONBLOCK) == -1)
548 	fatal(2, "Can't set file mode flags on stdin: %m");
549 
550     if (verbose)
551 	logf("alarm");
552 }
553 
554 void unalarm()
555 {
556     int flags;
557 
558     if ((flags = fcntl(0, F_GETFL, 0)) == -1)
559 	fatal(2, "Can't get file mode flags on stdin: %m");
560 
561     if (fcntl(0, F_SETFL, flags & ~O_NONBLOCK) == -1)
562 	fatal(2, "Can't set file mode flags on stdin: %m");
563 }
564 
565 SIGTYPE sigint(signo)
566 int signo;
567 {
568     fatal(2, "SIGINT");
569 }
570 
571 SIGTYPE sigterm(signo)
572 int signo;
573 {
574     fatal(2, "SIGTERM");
575 }
576 
577 SIGTYPE sighup(signo)
578 int signo;
579 {
580     fatal(2, "SIGHUP");
581 }
582 
583 void init()
584 {
585     signal(SIGINT, sigint);
586     signal(SIGTERM, sigterm);
587     signal(SIGHUP, sighup);
588 
589     set_tty_parameters();
590     signal(SIGALRM, sigalrm);
591     alarm(0);
592     alarmed = 0;
593 }
594 
595 void set_tty_parameters()
596 {
597 #if defined(get_term_param)
598     term_parms t;
599 
600     if (get_term_param (&t) < 0)
601 	fatal(2, "Can't get terminal parameters: %m");
602 
603     saved_tty_parameters = t;
604     have_tty_parameters  = 1;
605 
606     t.c_iflag     |= IGNBRK | ISTRIP | IGNPAR;
607     t.c_oflag      = 0;
608     t.c_lflag      = 0;
609     t.c_cc[VERASE] =
610     t.c_cc[VKILL]  = 0;
611     t.c_cc[VMIN]   = 1;
612     t.c_cc[VTIME]  = 0;
613 
614     if (set_term_param (&t) < 0)
615 	fatal(2, "Can't set terminal parameters: %m");
616 #endif
617 }
618 
619 void break_sequence()
620 {
621 #ifdef TERMIOS
622     tcsendbreak (0, 0);
623 #endif
624 }
625 
626 void terminate(status)
627 int status;
628 {
629     static int terminating = 0;
630 
631     if (terminating)
632 	exit(status);
633     terminating = 1;
634     echo_stderr(-1);
635 /*
636  * Allow the last of the report string to be gathered before we terminate.
637  */
638     if (report_gathering) {
639 	int c, rep_len;
640 
641 	rep_len = strlen(report_buffer);
642 	while (rep_len + 1 <= sizeof(report_buffer)) {
643 	    alarm(1);
644 	    c = get_char();
645 	    alarm(0);
646 	    if (c < 0 || iscntrl(c))
647 		break;
648 	    report_buffer[rep_len] = c;
649 	    ++rep_len;
650 	}
651 	report_buffer[rep_len] = 0;
652 	fprintf (report_fp, "chat:  %s\n", report_buffer);
653     }
654     if (report_file != (char *) 0 && report_fp != (FILE *) NULL) {
655 	if (verbose)
656 	    fprintf (report_fp, "Closing \"%s\".\n", report_file);
657 	fclose (report_fp);
658 	report_fp = (FILE *) NULL;
659     }
660 
661 #if defined(get_term_param)
662     if (have_tty_parameters) {
663 	if (set_term_param (&saved_tty_parameters) < 0)
664 	    fatal(2, "Can't restore terminal parameters: %m");
665     }
666 #endif
667 
668     exit(status);
669 }
670 
671 /*
672  *	'Clean up' this string.
673  */
674 char *clean(s, sending)
675 register char *s;
676 int sending;  /* set to 1 when sending (putting) this string. */
677 {
678     char temp[STR_LEN], env_str[STR_LEN], cur_chr;
679     register char *s1, *phchar;
680     int add_return = sending;
681 #define isoctal(chr)	(((chr) >= '0') && ((chr) <= '7'))
682 #define isalnumx(chr)	((((chr) >= '0') && ((chr) <= '9')) \
683 			 || (((chr) >= 'a') && ((chr) <= 'z')) \
684 			 || (((chr) >= 'A') && ((chr) <= 'Z')) \
685 			 || (chr) == '_')
686 
687     s1 = temp;
688     while (*s) {
689 	cur_chr = *s++;
690 	if (cur_chr == '^') {
691 	    cur_chr = *s++;
692 	    if (cur_chr == '\0') {
693 		*s1++ = '^';
694 		break;
695 	    }
696 	    cur_chr &= 0x1F;
697 	    if (cur_chr != 0) {
698 		*s1++ = cur_chr;
699 	    }
700 	    continue;
701 	}
702 
703 	if (use_env && cur_chr == '$') {		/* ARI */
704 	    phchar = env_str;
705 	    while (isalnumx(*s))
706 		*phchar++ = *s++;
707 	    *phchar = '\0';
708 	    phchar = getenv(env_str);
709 	    if (phchar)
710 		while (*phchar)
711 		    *s1++ = *phchar++;
712 	    continue;
713 	}
714 
715 	if (cur_chr != '\\') {
716 	    *s1++ = cur_chr;
717 	    continue;
718 	}
719 
720 	cur_chr = *s++;
721 	if (cur_chr == '\0') {
722 	    if (sending) {
723 		*s1++ = '\\';
724 		*s1++ = '\\';
725 	    }
726 	    break;
727 	}
728 
729 	switch (cur_chr) {
730 	case 'b':
731 	    *s1++ = '\b';
732 	    break;
733 
734 	case 'c':
735 	    if (sending && *s == '\0')
736 		add_return = 0;
737 	    else
738 		*s1++ = cur_chr;
739 	    break;
740 
741 	case '\\':
742 	case 'K':
743 	case 'p':
744 	case 'd':
745 	    if (sending)
746 		*s1++ = '\\';
747 	    *s1++ = cur_chr;
748 	    break;
749 
750 	case 'T':
751 	    if (sending && phone_num) {
752 		for (phchar = phone_num; *phchar != '\0'; phchar++)
753 		    *s1++ = *phchar;
754 	    }
755 	    else {
756 		*s1++ = '\\';
757 		*s1++ = 'T';
758 	    }
759 	    break;
760 
761 	case 'U':
762 	    if (sending && phone_num2) {
763 		for (phchar = phone_num2; *phchar != '\0'; phchar++)
764 		    *s1++ = *phchar;
765 	    }
766 	    else {
767 		*s1++ = '\\';
768 		*s1++ = 'U';
769 	    }
770 	    break;
771 
772 	case 'q':
773 	    quiet = 1;
774 	    break;
775 
776 	case 'r':
777 	    *s1++ = '\r';
778 	    break;
779 
780 	case 'n':
781 	    *s1++ = '\n';
782 	    break;
783 
784 	case 's':
785 	    *s1++ = ' ';
786 	    break;
787 
788 	case 't':
789 	    *s1++ = '\t';
790 	    break;
791 
792 	case 'N':
793 	    if (sending) {
794 		*s1++ = '\\';
795 		*s1++ = '\0';
796 	    }
797 	    else
798 		*s1++ = 'N';
799 	    break;
800 
801 	case '$':			/* ARI */
802 	    if (use_env) {
803 		*s1++ = cur_chr;
804 		break;
805 	    }
806 	    /* FALL THROUGH */
807 
808 	default:
809 	    if (isoctal (cur_chr)) {
810 		cur_chr &= 0x07;
811 		if (isoctal (*s)) {
812 		    cur_chr <<= 3;
813 		    cur_chr |= *s++ - '0';
814 		    if (isoctal (*s)) {
815 			cur_chr <<= 3;
816 			cur_chr |= *s++ - '0';
817 		    }
818 		}
819 
820 		if (cur_chr != 0 || sending) {
821 		    if (sending && (cur_chr == '\\' || cur_chr == 0))
822 			*s1++ = '\\';
823 		    *s1++ = cur_chr;
824 		}
825 		break;
826 	    }
827 
828 	    if (sending)
829 		*s1++ = '\\';
830 	    *s1++ = cur_chr;
831 	    break;
832 	}
833     }
834 
835     if (add_return)
836 	*s1++ = '\r';
837 
838     *s1++ = '\0'; /* guarantee closure */
839     *s1++ = '\0'; /* terminate the string */
840     return dup_mem (temp, (size_t) (s1 - temp)); /* may have embedded nuls */
841 }
842 
843 /*
844  * A modified version of 'strtok'. This version skips \ sequences.
845  */
846 
847 char *expect_strtok (s, term)
848      char *s, *term;
849 {
850     static  char *str   = "";
851     int	    escape_flag = 0;
852     char   *result;
853 
854 /*
855  * If a string was specified then do initial processing.
856  */
857     if (s)
858 	str = s;
859 
860 /*
861  * If this is the escape flag then reset it and ignore the character.
862  */
863     if (*str)
864 	result = str;
865     else
866 	result = (char *) 0;
867 
868     while (*str) {
869 	if (escape_flag) {
870 	    escape_flag = 0;
871 	    ++str;
872 	    continue;
873 	}
874 
875 	if (*str == '\\') {
876 	    ++str;
877 	    escape_flag = 1;
878 	    continue;
879 	}
880 
881 /*
882  * If this is not in the termination string, continue.
883  */
884 	if (strchr (term, *str) == (char *) 0) {
885 	    ++str;
886 	    continue;
887 	}
888 
889 /*
890  * This is the terminator. Mark the end of the string and stop.
891  */
892 	*str++ = '\0';
893 	break;
894     }
895     return (result);
896 }
897 
898 /*
899  * Process the expect string
900  */
901 
902 void chat_expect (s)
903 char *s;
904 {
905     char *expect;
906     char *reply;
907 
908     if (strcmp(s, "HANGUP") == 0) {
909 	++hup_next;
910         return;
911     }
912 
913     if (strcmp(s, "ABORT") == 0) {
914 	++abort_next;
915 	return;
916     }
917 
918     if (strcmp(s, "CLR_ABORT") == 0) {
919 	++clear_abort_next;
920 	return;
921     }
922 
923     if (strcmp(s, "REPORT") == 0) {
924 	++report_next;
925 	return;
926     }
927 
928     if (strcmp(s, "CLR_REPORT") == 0) {
929 	++clear_report_next;
930 	return;
931     }
932 
933     if (strcmp(s, "TIMEOUT") == 0) {
934 	++timeout_next;
935 	return;
936     }
937 
938     if (strcmp(s, "ECHO") == 0) {
939 	++echo_next;
940 	return;
941     }
942 
943     if (strcmp(s, "SAY") == 0) {
944 	++say_next;
945 	return;
946     }
947 
948 /*
949  * Fetch the expect and reply string.
950  */
951     for (;;) {
952 	expect = expect_strtok (s, "-");
953 	s      = (char *) 0;
954 
955 	if (expect == (char *) 0)
956 	    return;
957 
958 	reply = expect_strtok (s, "-");
959 
960 /*
961  * Handle the expect string. If successful then exit.
962  */
963 	if (get_string (expect))
964 	    return;
965 
966 /*
967  * If there is a sub-reply string then send it. Otherwise any condition
968  * is terminal.
969  */
970 	if (reply == (char *) 0 || exit_code != 3)
971 	    break;
972 
973 	chat_send (reply);
974     }
975 
976 /*
977  * The expectation did not occur. This is terminal.
978  */
979     if (fail_reason)
980 	logf("Failed (%s)", fail_reason);
981     else
982 	logf("Failed");
983     terminate(exit_code);
984 }
985 
986 /*
987  * Translate the input character to the appropriate string for printing
988  * the data.
989  */
990 
991 char *character(c)
992 int c;
993 {
994     static char string[10];
995     char *meta;
996 
997     meta = (c & 0x80) ? "M-" : "";
998     c &= 0x7F;
999 
1000     if (c < 32)
1001 	sprintf(string, "%s^%c", meta, (int)c + '@');
1002     else if (c == 127)
1003 	sprintf(string, "%s^?", meta);
1004     else
1005 	sprintf(string, "%s%c", meta, c);
1006 
1007     return (string);
1008 }
1009 
1010 /*
1011  *  process the reply string
1012  */
1013 void chat_send (s)
1014 register char *s;
1015 {
1016     char file_data[STR_LEN];
1017 
1018     if (say_next) {
1019 	say_next = 0;
1020 	s = clean(s, 1);
1021 	write(2, s, strlen(s));
1022         free(s);
1023 	return;
1024     }
1025 
1026     if (hup_next) {
1027         hup_next = 0;
1028 	if (strcmp(s, "OFF") == 0)
1029            signal(SIGHUP, SIG_IGN);
1030         else
1031            signal(SIGHUP, sighup);
1032         return;
1033     }
1034 
1035     if (echo_next) {
1036 	echo_next = 0;
1037 	echo = (strcmp(s, "ON") == 0);
1038 	return;
1039     }
1040 
1041     if (abort_next) {
1042 	char *s1;
1043 
1044 	abort_next = 0;
1045 
1046 	if (n_aborts >= MAX_ABORTS)
1047 	    fatal(2, "Too many ABORT strings");
1048 
1049 	s1 = clean(s, 0);
1050 
1051 	if (strlen(s1) > strlen(s)
1052 	    || strlen(s1) + 1 > sizeof(fail_buffer))
1053 	    fatal(1, "Illegal or too-long ABORT string ('%v')", s);
1054 
1055 	abort_string[n_aborts++] = s1;
1056 
1057 	if (verbose)
1058 	    logf("abort on (%v)", s);
1059 	return;
1060     }
1061 
1062     if (clear_abort_next) {
1063 	char *s1;
1064 	int   i;
1065         int   old_max;
1066 	int   pack = 0;
1067 
1068 	clear_abort_next = 0;
1069 
1070 	s1 = clean(s, 0);
1071 
1072 	if (strlen(s1) > strlen(s)
1073 	    || strlen(s1) + 1 > sizeof(fail_buffer))
1074 	    fatal(1, "Illegal or too-long CLR_ABORT string ('%v')", s);
1075 
1076         old_max = n_aborts;
1077 	for (i=0; i < n_aborts; i++) {
1078 	    if ( strcmp(s1,abort_string[i]) == 0 ) {
1079 		free(abort_string[i]);
1080 		abort_string[i] = NULL;
1081 		pack++;
1082 		n_aborts--;
1083 		if (verbose)
1084 		    logf("clear abort on (%v)", s);
1085 	    }
1086 	}
1087         free(s1);
1088 	if (pack)
1089 	    pack_array(abort_string,old_max);
1090 	return;
1091     }
1092 
1093     if (report_next) {
1094 	char *s1;
1095 
1096 	report_next = 0;
1097 	if (n_reports >= MAX_REPORTS)
1098 	    fatal(2, "Too many REPORT strings");
1099 
1100 	s1 = clean(s, 0);
1101 
1102 	if (strlen(s1) > strlen(s) || strlen(s1) > sizeof fail_buffer - 1)
1103 	    fatal(1, "Illegal or too-long REPORT string ('%v')", s);
1104 
1105 	report_string[n_reports++] = s1;
1106 
1107 	if (verbose)
1108 	    logf("report (%v)", s);
1109 	return;
1110     }
1111 
1112     if (clear_report_next) {
1113 	char *s1;
1114 	int   i;
1115 	int   old_max;
1116 	int   pack = 0;
1117 
1118 	clear_report_next = 0;
1119 
1120 	s1 = clean(s, 0);
1121 
1122 	if (strlen(s1) > strlen(s) || strlen(s1) > sizeof fail_buffer - 1)
1123 	    fatal(1, "Illegal or too-long REPORT string ('%v')", s);
1124 
1125 	old_max = n_reports;
1126 	for (i=0; i < n_reports; i++) {
1127 	    if ( strcmp(s1,report_string[i]) == 0 ) {
1128 		free(report_string[i]);
1129 		report_string[i] = NULL;
1130 		pack++;
1131 		n_reports--;
1132 		if (verbose)
1133 		    logf("clear report (%v)", s);
1134 	    }
1135 	}
1136         free(s1);
1137         if (pack)
1138 	    pack_array(report_string,old_max);
1139 
1140 	return;
1141     }
1142 
1143     if (timeout_next) {
1144 	timeout_next = 0;
1145 	timeout = atoi(s);
1146 
1147 	if (timeout <= 0)
1148 	    timeout = DEFAULT_CHAT_TIMEOUT;
1149 
1150 	if (verbose)
1151 	    logf("timeout set to %d seconds", timeout);
1152 
1153 	return;
1154     }
1155 
1156     /*
1157      * The syntax @filename means read the string to send from the
1158      * file `filename'.
1159      */
1160     if (s[0] == '@') {
1161 	/* skip the @ and any following white-space */
1162 	char *fn = s;
1163 	while (*++fn == ' ' || *fn == '\t')
1164 	    ;
1165 
1166 	if (*fn != 0) {
1167 	    FILE *f;
1168 	    int n = 0;
1169 
1170 	    /* open the file and read until STR_LEN-1 bytes or end-of-file */
1171 	    f = fopen(fn, "r");
1172 	    if (f == NULL)
1173 		fatal(1, "%s -- open failed: %m", fn);
1174 	    while (n < STR_LEN - 1) {
1175 		int nr = fread(&file_data[n], 1, STR_LEN - 1 - n, f);
1176 		if (nr < 0)
1177 		    fatal(1, "%s -- read error", fn);
1178 		if (nr == 0)
1179 		    break;
1180 		n += nr;
1181 	    }
1182 	    fclose(f);
1183 
1184 	    /* use the string we got as the string to send,
1185 	       but trim off the final newline if any. */
1186 	    if (n > 0 && file_data[n-1] == '\n')
1187 		--n;
1188 	    file_data[n] = 0;
1189 	    s = file_data;
1190 	}
1191     }
1192 
1193     if (strcmp(s, "EOT") == 0)
1194 	s = "^D\\c";
1195     else if (strcmp(s, "BREAK") == 0)
1196 	s = "\\K\\c";
1197 
1198     if (!put_string(s))
1199 	fatal(1, "Failed");
1200 }
1201 
1202 int get_char()
1203 {
1204     int status;
1205     char c;
1206 
1207     status = read(0, &c, 1);
1208 
1209     switch (status) {
1210     case 1:
1211 	return ((int)c & 0x7F);
1212 
1213     default:
1214 	logf("warning: read() on stdin returned %d", status);
1215 
1216     case -1:
1217 	if ((status = fcntl(0, F_GETFL, 0)) == -1)
1218 	    fatal(2, "Can't get file mode flags on stdin: %m");
1219 
1220 	if (fcntl(0, F_SETFL, status & ~O_NONBLOCK) == -1)
1221 	    fatal(2, "Can't set file mode flags on stdin: %m");
1222 
1223 	return (-1);
1224     }
1225 }
1226 
1227 int put_char(c)
1228 int c;
1229 {
1230     int status;
1231     char ch = c;
1232 
1233     usleep(10000);		/* inter-character typing delay (?) */
1234 
1235     status = write(1, &ch, 1);
1236 
1237     switch (status) {
1238     case 1:
1239 	return (0);
1240 
1241     default:
1242 	logf("warning: write() on stdout returned %d", status);
1243 
1244     case -1:
1245 	if ((status = fcntl(0, F_GETFL, 0)) == -1)
1246 	    fatal(2, "Can't get file mode flags on stdin, %m");
1247 
1248 	if (fcntl(0, F_SETFL, status & ~O_NONBLOCK) == -1)
1249 	    fatal(2, "Can't set file mode flags on stdin: %m");
1250 
1251 	return (-1);
1252     }
1253 }
1254 
1255 int write_char (c)
1256 int c;
1257 {
1258     if (alarmed || put_char(c) < 0) {
1259 	alarm(0);
1260 	alarmed = 0;
1261 
1262 	if (verbose) {
1263 	    if (errno == EINTR || errno == EWOULDBLOCK)
1264 		logf(" -- write timed out");
1265 	    else
1266 		logf(" -- write failed: %m");
1267 	}
1268 	return (0);
1269     }
1270     return (1);
1271 }
1272 
1273 int put_string (s)
1274 register char *s;
1275 {
1276     quiet = 0;
1277     s = clean(s, 1);
1278 
1279     if (verbose) {
1280 	if (quiet)
1281 	    logf("send (??????)");
1282 	else
1283 	    logf("send (%v)", s);
1284     }
1285 
1286     alarm(timeout); alarmed = 0;
1287 
1288     while (*s) {
1289 	register char c = *s++;
1290 
1291 	if (c != '\\') {
1292 	    if (!write_char (c))
1293 		return 0;
1294 	    continue;
1295 	}
1296 
1297 	c = *s++;
1298 	switch (c) {
1299 	case 'd':
1300 	    sleep(1);
1301 	    break;
1302 
1303 	case 'K':
1304 	    break_sequence();
1305 	    break;
1306 
1307 	case 'p':
1308 	    usleep(10000); 	/* 1/100th of a second (arg is microseconds) */
1309 	    break;
1310 
1311 	default:
1312 	    if (!write_char (c))
1313 		return 0;
1314 	    break;
1315 	}
1316     }
1317 
1318     alarm(0);
1319     alarmed = 0;
1320     return (1);
1321 }
1322 
1323 /*
1324  *	Echo a character to stderr.
1325  *	When called with -1, a '\n' character is generated when
1326  *	the cursor is not at the beginning of a line.
1327  */
1328 void echo_stderr(n)
1329 int n;
1330 {
1331     static int need_lf;
1332     char *s;
1333 
1334     switch (n) {
1335     case '\r':		/* ignore '\r' */
1336 	break;
1337     case -1:
1338 	if (need_lf == 0)
1339 	    break;
1340 	/* fall through */
1341     case '\n':
1342 	write(2, "\n", 1);
1343 	need_lf = 0;
1344 	break;
1345     default:
1346 	s = character(n);
1347 	write(2, s, strlen(s));
1348 	need_lf = 1;
1349 	break;
1350     }
1351 }
1352 
1353 /*
1354  *	'Wait for' this string to appear on this file descriptor.
1355  */
1356 int get_string(string)
1357 register char *string;
1358 {
1359     char temp[STR_LEN];
1360     int c, printed = 0, len, minlen;
1361     register char *s = temp, *end = s + STR_LEN;
1362     char *logged = temp;
1363 
1364     fail_reason = (char *)0;
1365     string = clean(string, 0);
1366     len = strlen(string);
1367     minlen = (len > sizeof(fail_buffer)? len: sizeof(fail_buffer)) - 1;
1368 
1369     if (verbose)
1370 	logf("expect (%v)", string);
1371 
1372     if (len > STR_LEN) {
1373 	logf("expect string is too long");
1374 	exit_code = 1;
1375 	return 0;
1376     }
1377 
1378     if (len == 0) {
1379 	if (verbose)
1380 	    logf("got it");
1381 	return (1);
1382     }
1383 
1384     alarm(timeout);
1385     alarmed = 0;
1386 
1387     while ( ! alarmed && (c = get_char()) >= 0) {
1388 	int n, abort_len, report_len;
1389 
1390 	if (echo)
1391 	    echo_stderr(c);
1392 	if (verbose && c == '\n') {
1393 	    if (s == logged)
1394 		logf("");	/* blank line */
1395 	    else
1396 		logf("%0.*v", s - logged, logged);
1397 	    logged = s + 1;
1398 	}
1399 
1400 	*s++ = c;
1401 
1402 	if (verbose && s >= logged + 80) {
1403 	    logf("%0.*v", s - logged, logged);
1404 	    logged = s;
1405 	}
1406 
1407 	if (Verbose) {
1408 	   if (c == '\n')
1409 	       fputc( '\n', stderr );
1410 	   else if (c != '\r')
1411 	       fprintf( stderr, "%s", character(c) );
1412 	}
1413 
1414 	if (!report_gathering) {
1415 	    for (n = 0; n < n_reports; ++n) {
1416 		if ((report_string[n] != (char*) NULL) &&
1417 		    s - temp >= (report_len = strlen(report_string[n])) &&
1418 		    strncmp(s - report_len, report_string[n], report_len) == 0) {
1419 		    time_t time_now   = time ((time_t*) NULL);
1420 		    struct tm* tm_now = localtime (&time_now);
1421 
1422 		    strftime (report_buffer, 20, "%b %d %H:%M:%S ", tm_now);
1423 		    strcat (report_buffer, report_string[n]);
1424 
1425 		    report_string[n] = (char *) NULL;
1426 		    report_gathering = 1;
1427 		    break;
1428 		}
1429 	    }
1430 	}
1431 	else {
1432 	    if (!iscntrl (c)) {
1433 		int rep_len = strlen (report_buffer);
1434 		report_buffer[rep_len]     = c;
1435 		report_buffer[rep_len + 1] = '\0';
1436 	    }
1437 	    else {
1438 		report_gathering = 0;
1439 		fprintf (report_fp, "chat:  %s\n", report_buffer);
1440 	    }
1441 	}
1442 
1443 	if (s - temp >= len &&
1444 	    c == string[len - 1] &&
1445 	    strncmp(s - len, string, len) == 0) {
1446 	    if (verbose) {
1447 		if (s > logged)
1448 		    logf("%0.*v", s - logged, logged);
1449 		logf(" -- got it\n");
1450 	    }
1451 
1452 	    alarm(0);
1453 	    alarmed = 0;
1454 	    return (1);
1455 	}
1456 
1457 	for (n = 0; n < n_aborts; ++n) {
1458 	    if (s - temp >= (abort_len = strlen(abort_string[n])) &&
1459 		strncmp(s - abort_len, abort_string[n], abort_len) == 0) {
1460 		if (verbose) {
1461 		    if (s > logged)
1462 			logf("%0.*v", s - logged, logged);
1463 		    logf(" -- failed");
1464 		}
1465 
1466 		alarm(0);
1467 		alarmed = 0;
1468 		exit_code = n + 4;
1469 		strcpy(fail_reason = fail_buffer, abort_string[n]);
1470 		return (0);
1471 	    }
1472 	}
1473 
1474 	if (s >= end) {
1475 	    if (logged < s - minlen) {
1476 		if (verbose)
1477 		    logf("%0.*v", s - logged, logged);
1478 		logged = s;
1479 	    }
1480 	    s -= minlen;
1481 	    memmove(temp, s, minlen);
1482 	    logged = temp + (logged - s);
1483 	    s = temp + minlen;
1484 	}
1485 
1486 	if (alarmed && verbose)
1487 	    logf("warning: alarm synchronization problem");
1488     }
1489 
1490     alarm(0);
1491 
1492     if (verbose && printed) {
1493 	if (alarmed)
1494 	    logf(" -- read timed out");
1495 	else
1496 	    logf(" -- read failed: %m");
1497     }
1498 
1499     exit_code = 3;
1500     alarmed   = 0;
1501     return (0);
1502 }
1503 
1504 /*
1505  * Gross kludge to handle Solaris versions >= 2.6 having usleep.
1506  */
1507 #ifdef SOL2
1508 #include <sys/param.h>
1509 #if MAXUID > 65536		/* then this is Solaris 2.6 or later */
1510 #undef NO_USLEEP
1511 #endif
1512 #endif /* SOL2 */
1513 
1514 #ifdef NO_USLEEP
1515 #include <sys/types.h>
1516 #include <sys/time.h>
1517 
1518 /*
1519   usleep -- support routine for 4.2BSD system call emulations
1520   last edit:  29-Oct-1984     D A Gwyn
1521   */
1522 
1523 extern int	  select();
1524 
1525 int
1526 usleep( usec )				  /* returns 0 if ok, else -1 */
1527     long		usec;		/* delay in microseconds */
1528 {
1529     static struct {		/* `timeval' */
1530 	long	tv_sec;		/* seconds */
1531 	long	tv_usec;	/* microsecs */
1532     } delay;	    		/* _select() timeout */
1533 
1534     delay.tv_sec  = usec / 1000000L;
1535     delay.tv_usec = usec % 1000000L;
1536 
1537     return select(0, (long *)0, (long *)0, (long *)0, &delay);
1538 }
1539 #endif
1540 
1541 void
1542 pack_array (array, end)
1543     char **array; /* The address of the array of string pointers */
1544     int    end;   /* The index of the next free entry before CLR_ */
1545 {
1546     int i, j;
1547 
1548     for (i = 0; i < end; i++) {
1549 	if (array[i] == NULL) {
1550 	    for (j = i+1; j < end; ++j)
1551 		if (array[j] != NULL)
1552 		    array[i++] = array[j];
1553 	    for (; i < end; ++i)
1554 		array[i] = NULL;
1555 	    break;
1556 	}
1557     }
1558 }
1559 
1560 /*
1561  * vfmtmsg - format a message into a buffer.  Like vsprintf except we
1562  * also specify the length of the output buffer, and we handle the
1563  * %m (error message) format.
1564  * Doesn't do floating-point formats.
1565  * Returns the number of chars put into buf.
1566  */
1567 #define OUTCHAR(c)	(buflen > 0? (--buflen, *buf++ = (c)): 0)
1568 
1569 int
1570 vfmtmsg(buf, buflen, fmt, args)
1571     char *buf;
1572     int buflen;
1573     const char *fmt;
1574     va_list args;
1575 {
1576     int c, i, n;
1577     int width, prec, fillch;
1578     int base, len, neg, quoted;
1579     unsigned long val = 0;
1580     char *str, *buf0;
1581     const char *f;
1582     unsigned char *p;
1583     char num[32];
1584     static char hexchars[] = "0123456789abcdef";
1585 
1586     buf0 = buf;
1587     --buflen;
1588     while (buflen > 0) {
1589 	for (f = fmt; *f != '%' && *f != 0; ++f)
1590 	    ;
1591 	if (f > fmt) {
1592 	    len = f - fmt;
1593 	    if (len > buflen)
1594 		len = buflen;
1595 	    memcpy(buf, fmt, len);
1596 	    buf += len;
1597 	    buflen -= len;
1598 	    fmt = f;
1599 	}
1600 	if (*fmt == 0)
1601 	    break;
1602 	c = *++fmt;
1603 	width = prec = 0;
1604 	fillch = ' ';
1605 	if (c == '0') {
1606 	    fillch = '0';
1607 	    c = *++fmt;
1608 	}
1609 	if (c == '*') {
1610 	    width = va_arg(args, int);
1611 	    c = *++fmt;
1612 	} else {
1613 	    while (isdigit(c)) {
1614 		width = width * 10 + c - '0';
1615 		c = *++fmt;
1616 	    }
1617 	}
1618 	if (c == '.') {
1619 	    c = *++fmt;
1620 	    if (c == '*') {
1621 		prec = va_arg(args, int);
1622 		c = *++fmt;
1623 	    } else {
1624 		while (isdigit(c)) {
1625 		    prec = prec * 10 + c - '0';
1626 		    c = *++fmt;
1627 		}
1628 	    }
1629 	}
1630 	str = 0;
1631 	base = 0;
1632 	neg = 0;
1633 	++fmt;
1634 	switch (c) {
1635 	case 'd':
1636 	    i = va_arg(args, int);
1637 	    if (i < 0) {
1638 		neg = 1;
1639 		val = -i;
1640 	    } else
1641 		val = i;
1642 	    base = 10;
1643 	    break;
1644 	case 'o':
1645 	    val = va_arg(args, unsigned int);
1646 	    base = 8;
1647 	    break;
1648 	case 'x':
1649 	    val = va_arg(args, unsigned int);
1650 	    base = 16;
1651 	    break;
1652 	case 'p':
1653 	    val = (unsigned long) va_arg(args, void *);
1654 	    base = 16;
1655 	    neg = 2;
1656 	    break;
1657 	case 's':
1658 	    str = va_arg(args, char *);
1659 	    break;
1660 	case 'c':
1661 	    num[0] = va_arg(args, int);
1662 	    num[1] = 0;
1663 	    str = num;
1664 	    break;
1665 	case 'm':
1666 	    str = strerror(errno);
1667 	    break;
1668 	case 'v':		/* "visible" string */
1669 	case 'q':		/* quoted string */
1670 	    quoted = c == 'q';
1671 	    p = va_arg(args, unsigned char *);
1672 	    if (fillch == '0' && prec > 0) {
1673 		n = prec;
1674 	    } else {
1675 		n = strlen((char *)p);
1676 		if (prec > 0 && prec < n)
1677 		    n = prec;
1678 	    }
1679 	    while (n > 0 && buflen > 0) {
1680 		c = *p++;
1681 		--n;
1682 		if (!quoted && c >= 0x80) {
1683 		    OUTCHAR('M');
1684 		    OUTCHAR('-');
1685 		    c -= 0x80;
1686 		}
1687 		if (quoted && (c == '"' || c == '\\'))
1688 		    OUTCHAR('\\');
1689 		if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
1690 		    if (quoted) {
1691 			OUTCHAR('\\');
1692 			switch (c) {
1693 			case '\t':	OUTCHAR('t');	break;
1694 			case '\n':	OUTCHAR('n');	break;
1695 			case '\b':	OUTCHAR('b');	break;
1696 			case '\f':	OUTCHAR('f');	break;
1697 			default:
1698 			    OUTCHAR('x');
1699 			    OUTCHAR(hexchars[c >> 4]);
1700 			    OUTCHAR(hexchars[c & 0xf]);
1701 			}
1702 		    } else {
1703 			if (c == '\t')
1704 			    OUTCHAR(c);
1705 			else {
1706 			    OUTCHAR('^');
1707 			    OUTCHAR(c ^ 0x40);
1708 			}
1709 		    }
1710 		} else
1711 		    OUTCHAR(c);
1712 	    }
1713 	    continue;
1714 	default:
1715 	    *buf++ = '%';
1716 	    if (c != '%')
1717 		--fmt;		/* so %z outputs %z etc. */
1718 	    --buflen;
1719 	    continue;
1720 	}
1721 	if (base != 0) {
1722 	    str = num + sizeof(num);
1723 	    *--str = 0;
1724 	    while (str > num + neg) {
1725 		*--str = hexchars[val % base];
1726 		val = val / base;
1727 		if (--prec <= 0 && val == 0)
1728 		    break;
1729 	    }
1730 	    switch (neg) {
1731 	    case 1:
1732 		*--str = '-';
1733 		break;
1734 	    case 2:
1735 		*--str = 'x';
1736 		*--str = '0';
1737 		break;
1738 	    }
1739 	    len = num + sizeof(num) - 1 - str;
1740 	} else {
1741 	    len = strlen(str);
1742 	    if (prec > 0 && len > prec)
1743 		len = prec;
1744 	}
1745 	if (width > 0) {
1746 	    if (width > buflen)
1747 		width = buflen;
1748 	    if ((n = width - len) > 0) {
1749 		buflen -= n;
1750 		for (; n > 0; --n)
1751 		    *buf++ = fillch;
1752 	    }
1753 	}
1754 	if (len > buflen)
1755 	    len = buflen;
1756 	memcpy(buf, str, len);
1757 	buf += len;
1758 	buflen -= len;
1759     }
1760     *buf = 0;
1761     return buf - buf0;
1762 }
1763