2 * utils.c - various utility functions used in pppd.
4 * Copyright (c) 1999 The Australian National University.
7 * Redistribution and use in source and binary forms are permitted
8 * provided that the above copyright notice and this paragraph are
9 * duplicated in all such forms and that any documentation,
10 * advertising materials, and other materials related to such
11 * distribution and use acknowledge that the software was developed
12 * by the Australian National University. The name of the University
13 * may not be used to endorse or promote products derived from this
14 * software without specific prior written permission.
15 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
17 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 #define RCSID "$Id: utils.c,v 1.13 2001/03/16 02:08:13 paulus Exp $"
34 #include <sys/param.h>
35 #include <sys/types.h>
38 #include <sys/resource.h>
40 #include <sys/socket.h>
41 #include <netinet/in.h>
43 #include <sys/mkdev.h>
48 static const char rcsid[] = RCSID;
51 extern char *strerror();
54 static void logit __P((int, char *, va_list));
55 static void log_write __P((int, char *));
56 static void vslp_printer __P((void *, char *, ...));
57 static void format_packet __P((u_char *, int, void (*) (void *, char *, ...),
66 * strlcpy - like strcpy/strncpy, doesn't overflow destination buffer,
67 * always leaves destination null-terminated (for len > 0).
70 strlcpy(dest, src, len)
75 size_t ret = strlen(src);
81 strncpy(dest, src, len - 1);
89 * strlcat - like strcat/strncat, doesn't overflow destination buffer,
90 * always leaves destination null-terminated (for len > 0).
93 strlcat(dest, src, len)
98 size_t dlen = strlen(dest);
100 return dlen + strlcpy(dest + dlen, src, (len > dlen? len - dlen: 0));
105 * slprintf - format a message into a buffer. Like sprintf except we
106 * also specify the length of the output buffer, and we handle
107 * %r (recursive format), %m (error message), %v (visible string),
108 * %q (quoted string), %t (current time) and %I (IP address) formats.
109 * Doesn't do floating-point formats.
110 * Returns the number of chars put into buf.
113 slprintf __V((char *buf, int buflen, char *fmt, ...))
118 #if defined(__STDC__)
125 buf = va_arg(args, char *);
126 buflen = va_arg(args, int);
127 fmt = va_arg(args, char *);
129 n = vslprintf(buf, buflen, fmt, args);
135 * vslprintf - like slprintf, takes a va_list instead of a list of args.
137 #define OUTCHAR(c) (buflen > 0? (--buflen, *buf++ = (c)): 0)
140 vslprintf(buf, buflen, fmt, args)
147 int width, prec, fillch;
148 int base, len, neg, quoted;
149 unsigned long val = 0;
150 char *str, *f, *buf0;
155 static char hexchars[] = "0123456789abcdef";
156 struct buffer_info bufinfo;
161 for (f = fmt; *f != '%' && *f != 0; ++f)
167 memcpy(buf, fmt, len);
183 width = va_arg(args, int);
187 width = width * 10 + c - '0';
194 prec = va_arg(args, int);
199 prec = prec * 10 + c - '0';
210 i = va_arg(args, int);
219 val = va_arg(args, unsigned int);
223 val = va_arg(args, unsigned int);
228 val = va_arg(args, unsigned int);
232 val = (unsigned long) va_arg(args, void *);
237 str = va_arg(args, char *);
240 num[0] = va_arg(args, int);
245 str = strerror(errno);
248 ip = va_arg(args, u_int32_t);
250 slprintf(num, sizeof(num), "%d.%d.%d.%d", (ip >> 24) & 0xff,
251 (ip >> 16) & 0xff, (ip >> 8) & 0xff, ip & 0xff);
255 f = va_arg(args, char *);
257 n = vslprintf(buf, buflen + 1, f, va_arg(args, va_list));
259 /* On the powerpc, a va_list is an array of 1 structure */
260 n = vslprintf(buf, buflen + 1, f, va_arg(args, void *));
268 str += 4; /* chop off the day name */
269 str[15] = 0; /* chop off year and newline */
271 case 'v': /* "visible" string */
272 case 'q': /* quoted string */
274 p = va_arg(args, unsigned char *);
275 if (fillch == '0' && prec >= 0) {
278 n = strlen((char *)p);
279 if (prec >= 0 && n > prec)
282 while (n > 0 && buflen > 0) {
285 if (!quoted && c >= 0x80) {
290 if (quoted && (c == '"' || c == '\\'))
292 if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
296 case '\t': OUTCHAR('t'); break;
297 case '\n': OUTCHAR('n'); break;
298 case '\b': OUTCHAR('b'); break;
299 case '\f': OUTCHAR('f'); break;
302 OUTCHAR(hexchars[c >> 4]);
303 OUTCHAR(hexchars[c & 0xf]);
317 case 'P': /* print PPP packet */
319 bufinfo.len = buflen + 1;
320 p = va_arg(args, unsigned char *);
321 n = va_arg(args, int);
322 format_packet(p, n, vslp_printer, &bufinfo);
324 buflen = bufinfo.len - 1;
327 p = va_arg(args, unsigned char *);
328 for (n = prec; n > 0; --n) {
332 OUTCHAR(hexchars[(c >> 4) & 0xf]);
333 OUTCHAR(hexchars[c & 0xf]);
339 --fmt; /* so %z outputs %z etc. */
344 str = num + sizeof(num);
346 while (str > num + neg) {
347 *--str = hexchars[val % base];
349 if (--prec <= 0 && val == 0)
361 len = num + sizeof(num) - 1 - str;
364 if (prec >= 0 && len > prec)
370 if ((n = width - len) > 0) {
378 memcpy(buf, str, len);
387 * vslp_printer - used in processing a %P format
390 vslp_printer __V((void *arg, char *fmt, ...))
394 struct buffer_info *bi;
396 #if defined(__STDC__)
402 arg = va_arg(pvar, void *);
403 fmt = va_arg(pvar, char *);
406 bi = (struct buffer_info *) arg;
407 n = vslprintf(bi->ptr, bi->len, fmt, pvar);
416 * log_packet - format a packet and log it.
420 log_packet(p, len, prefix, level)
426 init_pr_log(prefix, level);
427 format_packet(p, len, pr_log, &level);
433 * format_packet - make a readable representation of a packet,
434 * calling `printer(arg, format, ...)' to output it.
437 format_packet(p, len, printer, arg)
440 void (*printer) __P((void *, char *, ...));
445 struct protent *protp;
447 if (len >= PPP_HDRLEN && p[0] == PPP_ALLSTATIONS && p[1] == PPP_UI) {
451 for (i = 0; (protp = protocols[i]) != NULL; ++i)
452 if (proto == protp->protocol)
455 printer(arg, "[%s", protp->name);
456 n = (*protp->printpkt)(p, len, printer, arg);
461 for (i = 0; (protp = protocols[i]) != NULL; ++i)
462 if (proto == (protp->protocol & ~0x8000))
464 if (protp != 0 && protp->data_name != 0) {
465 printer(arg, "[%s data]", protp->data_name);
467 printer(arg, "%.8B ...", p);
469 printer(arg, "%.*B", len, p);
472 printer(arg, "[proto=0x%x]", proto);
477 printer(arg, "%.32B ...", p);
479 printer(arg, "%.*B", len, p);
483 * init_pr_log, end_pr_log - initialize and finish use of pr_log.
486 static char line[256]; /* line to be logged accumulated here */
487 static char *linep; /* current pointer within line */
488 static int llevel; /* level for logging */
491 init_pr_log(prefix, level)
496 if (prefix != NULL) {
497 strlcpy(line, prefix, sizeof(line));
498 linep = line + strlen(line);
508 log_write(llevel, line);
513 * pr_log - printer routine for outputting to syslog
516 pr_log __V((void *arg, char *fmt, ...))
523 #if defined(__STDC__)
529 arg = va_arg(pvar, void *);
530 fmt = va_arg(pvar, char *);
533 n = vslprintf(buf, sizeof(buf), fmt, pvar);
537 eol = strchr(buf, '\n');
539 l = (eol == NULL)? n: eol - buf;
540 if (linep + l < line + sizeof(line)) {
542 memcpy(linep, buf, l);
548 eol = strchr(p, '\n');
551 log_write(llevel, line);
555 while (eol != NULL) {
557 log_write(llevel, p);
559 eol = strchr(p, '\n');
562 /* assumes sizeof(buf) <= sizeof(line) */
571 * print_string - print a readable representation of a string using
575 print_string(p, len, printer, arg)
578 void (*printer) __P((void *, char *, ...));
584 for (; len > 0; --len) {
586 if (' ' <= c && c <= '~') {
587 if (c == '\\' || c == '"')
589 printer(arg, "%c", c);
602 printer(arg, "\\%.3o", c);
610 * logit - does the hard work for fatal et al.
613 logit(level, fmt, args)
621 n = vslprintf(buf, sizeof(buf), fmt, args);
622 log_write(level, buf);
626 log_write(level, buf)
630 syslog(level, "%s", buf);
631 if (log_to_fd >= 0 && (level != LOG_DEBUG || debug)) {
634 if (n > 0 && buf[n-1] == '\n')
636 if (write(log_to_fd, buf, n) != n
637 || write(log_to_fd, "\n", 1) != 1)
643 * fatal - log an error message and die horribly.
646 fatal __V((char *fmt, ...))
650 #if defined(__STDC__)
655 fmt = va_arg(pvar, char *);
658 logit(LOG_ERR, fmt, pvar);
661 die(1); /* as promised */
665 * error - log an error message.
668 error __V((char *fmt, ...))
672 #if defined(__STDC__)
677 fmt = va_arg(pvar, char *);
680 logit(LOG_ERR, fmt, pvar);
685 * warn - log a warning message.
688 warn __V((char *fmt, ...))
692 #if defined(__STDC__)
697 fmt = va_arg(pvar, char *);
700 logit(LOG_WARNING, fmt, pvar);
705 * notice - log a notice-level message.
708 notice __V((char *fmt, ...))
712 #if defined(__STDC__)
717 fmt = va_arg(pvar, char *);
720 logit(LOG_NOTICE, fmt, pvar);
725 * info - log an informational message.
728 info __V((char *fmt, ...))
732 #if defined(__STDC__)
737 fmt = va_arg(pvar, char *);
740 logit(LOG_INFO, fmt, pvar);
745 * dbglog - log a debug message.
748 dbglog __V((char *fmt, ...))
752 #if defined(__STDC__)
757 fmt = va_arg(pvar, char *);
760 logit(LOG_DEBUG, fmt, pvar);
764 /* Procedures for locking the serial device using a lock file. */
767 #define LOCK_DIR "/var/lock"
770 #define LOCK_DIR "/var/spool/locks"
772 #define LOCK_DIR "/var/spool/lock"
775 #endif /* LOCK_DIR */
777 static char lock_file[MAXPATHLEN];
780 * lock - create a lock file for the named device
789 result = mklock (dev, (void *) 0);
791 strlcpy(lock_file, sizeof(lock_file), dev);
796 notice("Device %s is locked by pid %d", dev, result);
798 error("Can't create lock file %s", lock_file);
803 char lock_buffer[12];
809 if (stat(dev, &sbuf) < 0) {
810 error("Can't get device number for %s: %m", dev);
813 if ((sbuf.st_mode & S_IFMT) != S_IFCHR) {
814 error("Can't lock %s: not a character device", dev);
817 slprintf(lock_file, sizeof(lock_file), "%s/LK.%03d.%03d.%03d",
818 LOCK_DIR, major(sbuf.st_dev),
819 major(sbuf.st_rdev), minor(sbuf.st_rdev));
823 if ((p = strrchr(dev, '/')) != NULL)
825 slprintf(lock_file, sizeof(lock_file), "%s/LCK..%s", LOCK_DIR, dev);
828 while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {
829 if (errno != EEXIST) {
830 error("Can't create lock file %s: %m", lock_file);
834 /* Read the lock file to find out who has the device locked. */
835 fd = open(lock_file, O_RDONLY, 0);
837 if (errno == ENOENT) /* This is just a timing problem. */
839 error("Can't open existing lock file %s: %m", lock_file);
843 n = read(fd, lock_buffer, 11);
845 n = read(fd, &pid, sizeof(pid));
846 #endif /* LOCK_BINARY */
850 error("Can't read pid from lock file %s", lock_file);
854 /* See if the process still exists. */
857 pid = atoi(lock_buffer);
858 #endif /* LOCK_BINARY */
860 return 1; /* somebody else locked it for us */
862 || (kill(pid, 0) == -1 && errno == ESRCH)) {
863 if (unlink (lock_file) == 0) {
864 notice("Removed stale lock on %s (pid %d)", dev, pid);
867 warn("Couldn't remove stale lock on %s", dev);
869 notice("Device %s is locked by pid %d", dev, pid);
880 slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
881 write (fd, lock_buffer, 11);
883 write(fd, &pid, sizeof (pid));
892 * relock - called to update our lockfile when we are about to detach,
893 * thus changing our pid (we fork, the child carries on, and the parent dies).
894 * Note that this is called by the parent, with pid equal to the pid
895 * of the child. This avoids a potential race which would exist if
896 * we had the child rewrite the lockfile (the parent might die first,
897 * and another process could think the lock was stale if it checked
898 * between when the parent died and the child rewrote the lockfile).
905 /* XXX is there a way to do this? */
910 char lock_buffer[12];
912 if (lock_file[0] == 0)
914 fd = open(lock_file, O_WRONLY, 0);
916 error("Couldn't reopen lock file %s: %m", lock_file);
922 slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
923 write (fd, lock_buffer, 11);
925 write(fd, &pid, sizeof(pid));
926 #endif /* LOCK_BINARY */
934 * unlock - remove our lockfile
941 (void) rmlock(lock_file, (void *) 0);