3 * David L Nugent <davidn@blaze.net.au>.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, is permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice immediately at the beginning of the file, without modification,
12 * this list of conditions, and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. This work was done expressly for inclusion into FreeBSD. Other use
17 * is permitted provided this notation is included.
18 * 4. Absolutely no warranty of function or purpose is made by the authors.
19 * 5. Modifications may be freely made to this file providing the above
22 * Modem chat module - send/expect style functions for getty
23 * For semi-intelligent modem handling.
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
29 #include <sys/types.h>
30 #include <sys/ioctl.h>
31 #include <sys/utsname.h>
43 #define PAUSE_CH (unsigned char)'\xff' /* pause kludge */
45 #define CHATDEBUG_RECEIVE 0x01
46 #define CHATDEBUG_SEND 0x02
47 #define CHATDEBUG_EXPECT 0x04
48 #define CHATDEBUG_MISC 0x08
50 #define CHATDEBUG_DEFAULT 0
51 #define CHAT_DEFAULT_TIMEOUT 10
54 static int chat_debug = CHATDEBUG_DEFAULT;
55 static int chat_alarm = CHAT_DEFAULT_TIMEOUT; /* Default */
57 static volatile int alarmed = 0;
60 static void chat_alrm(int);
61 static int chat_unalarm(void);
62 static int getdigit(unsigned char **, int, int);
63 static char **read_chat(char **);
64 static char *cleanchr(char **, unsigned char);
65 static char *cleanstr(const unsigned char *, int);
66 static const char *result(int);
67 static int chat_expect(const char *);
68 static int chat_send(char const *);
72 * alarm signal handler
73 * handle timeouts in read/write
74 * change stdin to non-blocking mode to prevent
75 * possible hang in read().
79 chat_alrm(int signo __unused)
85 signal(SIGALRM, chat_alrm);
86 ioctl(STDIN_FILENO, FIONBIO, &on);
91 * Turn back on blocking mode reset by chat_alrm()
98 return ioctl(STDIN_FILENO, FIONBIO, &off);
103 * convert a string of a given base (octal/hex) to binary
107 getdigit(unsigned char **ptr, int base, int max)
112 static const char xdigits[] = "0123456789abcdef";
114 for (i = 0, q = *ptr; i++ < max; ++q) {
116 const char * s = strchr(xdigits, tolower(*q));
118 if (s == NULL || (sval = s - xdigits) >= base)
120 val = (val * base) + sval;
129 * Convert a whitespace delimtied string into an array
130 * of strings, being expect/send pairs
134 read_chat(char **chatstr)
136 char *str = *chatstr;
143 if ((l=strlen(str)) > 0 && (tmp=malloc(l + 1)) != NULL &&
144 (res=malloc((l / 2 + 1) * sizeof(char *))) != NULL) {
145 static char ws[] = " \t";
148 for (l = 0, p = strtok(strcpy(tmp, str), ws);
150 p = strtok(NULL, ws))
152 unsigned char *q, *r;
155 for (q = r = (unsigned char *)p; *r; ++q)
159 /* handle special escapes */
183 case 'p': /* pause */
187 case 'S': /* space */
190 case 'x': /* hexdigit */
192 *r++ = getdigit(&q, 16, 2);
195 case '0': /* octal */
197 *r++ = getdigit(&q, 8, 3);
200 default: /* literal */
203 case 0: /* not past eos */
208 /* copy standard character */
213 /* Remove surrounding quotes, if any
215 if (*p == '"' || *p == '\'') {
216 q = strrchr(p+1, *p);
217 if (q != NULL && *q == *p && q[1] == '\0') {
236 * clean a character for display (ctrl/meta character)
240 cleanchr(char **buf, unsigned char ch)
243 static char tmpbuf[5];
244 char * tmp = buf ? *buf : tmpbuf;
256 } else if (ch == 127) {
270 * clean a string for display (ctrl/meta characters)
274 cleanstr(const unsigned char *s, int l)
276 static unsigned char * tmp = NULL;
277 static int tmplen = 0;
279 if (tmplen < l * 4 + 1)
280 tmp = realloc(tmp, tmplen = l * 4 + 1);
284 return (char *)"(mem alloc error)";
290 cleanchr(&p, s[i++]);
299 * return result as a pseudo-english word
305 static const char * results[] = {
306 "OK", "MEMERROR", "IOERROR", "TIMEOUT"
308 return results[r & 3];
314 * scan input for an expected string
318 chat_expect(const char *str)
322 if (chat_debug & CHATDEBUG_EXPECT)
323 syslog(LOG_DEBUG, "chat_expect '%s'", cleanstr(str, strlen(str)));
325 if ((len = strlen(str)) > 0) {
329 if ((got = malloc(len + 1)) == NULL)
333 memset(got, 0, len+1);
337 while (r == 0 && i < len) {
343 if (read(STDIN_FILENO, &ch, 1) == 1) {
345 if (chat_debug & CHATDEBUG_RECEIVE)
346 syslog(LOG_DEBUG, "chat_recv '%s' m=%d",
347 cleanchr(NULL, ch), i);
354 /* See if we can resync on a
355 * partial match in our buffer
357 while (j < i && memcmp(got + j, str, i - j) != 0)
360 memcpy(got, got + j, i - j);
374 if (chat_debug & CHATDEBUG_EXPECT)
375 syslog(LOG_DEBUG, "chat_expect %s", result(r));
387 chat_send(char const *str)
391 if (chat_debug && CHATDEBUG_SEND)
392 syslog(LOG_DEBUG, "chat_send '%s'", cleanstr(str, strlen(str)));
397 while (r == 0 && *str)
399 unsigned char ch = (unsigned char)*str++;
403 else if (ch == PAUSE_CH)
404 usleep(500000); /* 1/2 second */
406 usleep(10000); /* be kind to modem */
407 if (write(STDOUT_FILENO, &ch, 1) != 1)
416 if (chat_debug & CHATDEBUG_SEND)
417 syslog(LOG_DEBUG, "chat_send %s", result(r));
427 * -1 - no script supplied
428 * 0 - script terminated correctly
429 * 1 - invalid argument, expect string too large, etc.
430 * 2 - error on an I/O operation or fatal error condition
431 * 3 - timeout waiting for a simple string
434 * char *scrstr - unparsed chat script
435 * timeout - seconds timeout
436 * debug - debug value (bitmask)
440 getty_chat(char *scrstr, int timeout, int debug)
444 chat_alarm = timeout ? timeout : CHAT_DEFAULT_TIMEOUT;
447 if (scrstr != NULL) {
450 if (chat_debug & CHATDEBUG_MISC)
451 syslog(LOG_DEBUG, "getty_chat script='%s'", scrstr);
453 if ((script = read_chat(&scrstr)) != NULL) {
459 * We need to be in raw mode for all this
463 old_alarm = signal(SIGALRM, chat_alrm);
464 chat_unalarm(); /* Force blocking mode at start */
467 * This is the send/expect loop
469 while (r == 0 && script[i] != NULL)
470 if ((r = chat_expect(script[i++])) == 0 && script[i] != NULL)
471 r = chat_send(script[i++]);
473 signal(SIGALRM, old_alarm);
478 * Ensure stdin is in blocking mode
480 ioctl(STDIN_FILENO, FIONBIO, &off);
483 if (chat_debug & CHATDEBUG_MISC)
484 syslog(LOG_DEBUG, "getty_chat %s", result(r));