1/*
2 * utils.c - various utility functions used in pppd.
3 *
4 * Copyright (c) 1999 The Australian National University.
5 * All rights reserved.
6 *
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.
18 */
19
20#define RCSID	"$Id: utils.c,v 1.1.1.1 2008/10/15 03:30:13 james26_jang Exp $"
21
22#include <stdio.h>
23#include <ctype.h>
24#include <stdlib.h>
25#include <string.h>
26#include <unistd.h>
27#include <signal.h>
28#include <errno.h>
29#include <fcntl.h>
30#include <syslog.h>
31#include <netdb.h>
32#include <utmp.h>
33#include <pwd.h>
34#include <sys/param.h>
35#include <sys/types.h>
36#include <sys/wait.h>
37#include <sys/time.h>
38#include <sys/resource.h>
39#include <sys/stat.h>
40#include <sys/socket.h>
41#include <netinet/in.h>
42#ifdef SVR4
43#include <sys/mkdev.h>
44#endif
45
46#include "pppd.h"
47
48static const char rcsid[] = RCSID;
49
50#if defined(SUNOS4)
51extern char *strerror();
52#endif
53
54static void logit __P((int, char *, va_list));
55static void log_write __P((int, char *));
56static void vslp_printer __P((void *, char *, ...));
57static void format_packet __P((u_char *, int, void (*) (void *, char *, ...),
58			       void *));
59
60struct buffer_info {
61    char *ptr;
62    int len;
63};
64
65/* JYWeng 20031216: add to wanstatus.log */
66void saveWANStatus(char *currentstatus, int statusindex);
67
68/*
69 * strlcpy - like strcpy/strncpy, doesn't overflow destination buffer,
70 * always leaves destination null-terminated (for len > 0).
71 */
72size_t
73strlcpy(dest, src, len)
74    char *dest;
75    const char *src;
76    size_t len;
77{
78    size_t ret = strlen(src);
79
80    if (len != 0) {
81	if (ret < len)
82	    strcpy(dest, src);
83	else {
84	    strncpy(dest, src, len - 1);
85	    dest[len-1] = 0;
86	}
87    }
88    return ret;
89}
90
91/*
92 * strlcat - like strcat/strncat, doesn't overflow destination buffer,
93 * always leaves destination null-terminated (for len > 0).
94 */
95size_t
96strlcat(dest, src, len)
97    char *dest;
98    const char *src;
99    size_t len;
100{
101    size_t dlen = strlen(dest);
102
103    return dlen + strlcpy(dest + dlen, src, (len > dlen? len - dlen: 0));
104}
105
106
107/*
108 * slprintf - format a message into a buffer.  Like sprintf except we
109 * also specify the length of the output buffer, and we handle
110 * %r (recursive format), %m (error message), %v (visible string),
111 * %q (quoted string), %t (current time) and %I (IP address) formats.
112 * Doesn't do floating-point formats.
113 * Returns the number of chars put into buf.
114 */
115int
116slprintf __V((char *buf, int buflen, char *fmt, ...))
117{
118    va_list args;
119    int n;
120
121#if defined(__STDC__)
122    va_start(args, fmt);
123#else
124    char *buf;
125    int buflen;
126    char *fmt;
127    va_start(args);
128    buf = va_arg(args, char *);
129    buflen = va_arg(args, int);
130    fmt = va_arg(args, char *);
131#endif
132    n = vslprintf(buf, buflen, fmt, args);
133    va_end(args);
134    return n;
135}
136
137/*
138 * vslprintf - like slprintf, takes a va_list instead of a list of args.
139 */
140#define OUTCHAR(c)	(buflen > 0? (--buflen, *buf++ = (c)): 0)
141
142int
143vslprintf(buf, buflen, fmt, args)
144    char *buf;
145    int buflen;
146    char *fmt;
147    va_list args;
148{
149    int c, i, n;
150    int width, prec, fillch;
151    int base, len, neg, quoted;
152    unsigned long val = 0;
153    char *str, *f, *buf0;
154    unsigned char *p;
155    char num[32];
156    time_t t;
157    u_int32_t ip;
158    static char hexchars[] = "0123456789abcdef";
159    struct buffer_info bufinfo;
160
161    buf0 = buf;
162    --buflen;
163    while (buflen > 0) {
164	for (f = fmt; *f != '%' && *f != 0; ++f)
165	    ;
166	if (f > fmt) {
167	    len = f - fmt;
168	    if (len > buflen)
169		len = buflen;
170	    memcpy(buf, fmt, len);
171	    buf += len;
172	    buflen -= len;
173	    fmt = f;
174	}
175	if (*fmt == 0)
176	    break;
177	c = *++fmt;
178	width = 0;
179	prec = -1;
180	fillch = ' ';
181	if (c == '0') {
182	    fillch = '0';
183	    c = *++fmt;
184	}
185	if (c == '*') {
186	    width = va_arg(args, int);
187	    c = *++fmt;
188	} else {
189	    while (isdigit(c)) {
190		width = width * 10 + c - '0';
191		c = *++fmt;
192	    }
193	}
194	if (c == '.') {
195	    c = *++fmt;
196	    if (c == '*') {
197		prec = va_arg(args, int);
198		c = *++fmt;
199	    } else {
200		prec = 0;
201		while (isdigit(c)) {
202		    prec = prec * 10 + c - '0';
203		    c = *++fmt;
204		}
205	    }
206	}
207	str = 0;
208	base = 0;
209	neg = 0;
210	++fmt;
211	switch (c) {
212	case 'd':
213	    i = va_arg(args, int);
214	    if (i < 0) {
215		neg = 1;
216		val = -i;
217	    } else
218		val = i;
219	    base = 10;
220	    break;
221	case 'u':
222	    val = va_arg(args, unsigned int);
223	    base = 10;
224	    break;
225	case 'o':
226	    val = va_arg(args, unsigned int);
227	    base = 8;
228	    break;
229	case 'x':
230	case 'X':
231	    val = va_arg(args, unsigned int);
232	    base = 16;
233	    break;
234	case 'p':
235	    val = (unsigned long) va_arg(args, void *);
236	    base = 16;
237	    neg = 2;
238	    break;
239	case 's':
240	    str = va_arg(args, char *);
241	    break;
242	case 'c':
243	    num[0] = va_arg(args, int);
244	    num[1] = 0;
245	    str = num;
246	    break;
247	case 'm':
248	    str = strerror(errno);
249	    break;
250	case 'I':
251	    ip = va_arg(args, u_int32_t);
252	    ip = ntohl(ip);
253	    slprintf(num, sizeof(num), "%d.%d.%d.%d", (ip >> 24) & 0xff,
254		     (ip >> 16) & 0xff, (ip >> 8) & 0xff, ip & 0xff);
255	    str = num;
256	    break;
257	case 'r':
258	    f = va_arg(args, char *);
259#ifndef __powerpc__
260	    n = vslprintf(buf, buflen + 1, f, va_arg(args, va_list));
261#else
262	    /* On the powerpc, a va_list is an array of 1 structure */
263	    n = vslprintf(buf, buflen + 1, f, va_arg(args, void *));
264#endif
265	    buf += n;
266	    buflen -= n;
267	    continue;
268	case 't':
269	    time(&t);
270	    str = ctime(&t);
271	    str += 4;		/* chop off the day name */
272	    str[15] = 0;	/* chop off year and newline */
273	    break;
274	case 'v':		/* "visible" string */
275	case 'q':		/* quoted string */
276	    quoted = c == 'q';
277	    p = va_arg(args, unsigned char *);
278	    if (fillch == '0' && prec >= 0) {
279		n = prec;
280	    } else {
281		n = strlen((char *)p);
282		if (prec >= 0 && n > prec)
283		    n = prec;
284	    }
285	    while (n > 0 && buflen > 0) {
286		c = *p++;
287		--n;
288		if (!quoted && c >= 0x80) {
289		    OUTCHAR('M');
290		    OUTCHAR('-');
291		    c -= 0x80;
292		}
293		if (quoted && (c == '"' || c == '\\'))
294		    OUTCHAR('\\');
295		if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
296		    if (quoted) {
297			OUTCHAR('\\');
298			switch (c) {
299			case '\t':	OUTCHAR('t');	break;
300			case '\n':	OUTCHAR('n');	break;
301			case '\b':	OUTCHAR('b');	break;
302			case '\f':	OUTCHAR('f');	break;
303			default:
304			    OUTCHAR('x');
305			    OUTCHAR(hexchars[c >> 4]);
306			    OUTCHAR(hexchars[c & 0xf]);
307			}
308		    } else {
309			if (c == '\t')
310			    OUTCHAR(c);
311			else {
312			    OUTCHAR('^');
313			    OUTCHAR(c ^ 0x40);
314			}
315		    }
316		} else
317		    OUTCHAR(c);
318	    }
319	    continue;
320	case 'P':		/* print PPP packet */
321	    bufinfo.ptr = buf;
322	    bufinfo.len = buflen + 1;
323	    p = va_arg(args, unsigned char *);
324	    n = va_arg(args, int);
325	    format_packet(p, n, vslp_printer, &bufinfo);
326	    buf = bufinfo.ptr;
327	    buflen = bufinfo.len - 1;
328	    continue;
329	case 'B':
330	    p = va_arg(args, unsigned char *);
331	    for (n = prec; n > 0; --n) {
332		c = *p++;
333		if (fillch == ' ')
334		    OUTCHAR(' ');
335		OUTCHAR(hexchars[(c >> 4) & 0xf]);
336		OUTCHAR(hexchars[c & 0xf]);
337	    }
338	    continue;
339	default:
340	    *buf++ = '%';
341	    if (c != '%')
342		--fmt;		/* so %z outputs %z etc. */
343	    --buflen;
344	    continue;
345	}
346	if (base != 0) {
347	    str = num + sizeof(num);
348	    *--str = 0;
349	    while (str > num + neg) {
350		*--str = hexchars[val % base];
351		val = val / base;
352		if (--prec <= 0 && val == 0)
353		    break;
354	    }
355	    switch (neg) {
356	    case 1:
357		*--str = '-';
358		break;
359	    case 2:
360		*--str = 'x';
361		*--str = '0';
362		break;
363	    }
364	    len = num + sizeof(num) - 1 - str;
365	} else {
366	    len = strlen(str);
367	    if (prec >= 0 && len > prec)
368		len = prec;
369	}
370	if (width > 0) {
371	    if (width > buflen)
372		width = buflen;
373	    if ((n = width - len) > 0) {
374		buflen -= n;
375		for (; n > 0; --n)
376		    *buf++ = fillch;
377	    }
378	}
379	if (len > buflen)
380	    len = buflen;
381	memcpy(buf, str, len);
382	buf += len;
383	buflen -= len;
384    }
385    *buf = 0;
386    return buf - buf0;
387}
388
389/*
390 * vslp_printer - used in processing a %P format
391 */
392static void
393vslp_printer __V((void *arg, char *fmt, ...))
394{
395    int n;
396    va_list pvar;
397    struct buffer_info *bi;
398
399#if defined(__STDC__)
400    va_start(pvar, fmt);
401#else
402    void *arg;
403    char *fmt;
404    va_start(pvar);
405    arg = va_arg(pvar, void *);
406    fmt = va_arg(pvar, char *);
407#endif
408
409    bi = (struct buffer_info *) arg;
410    n = vslprintf(bi->ptr, bi->len, fmt, pvar);
411    va_end(pvar);
412
413    bi->ptr += n;
414    bi->len -= n;
415}
416
417#ifdef unused
418/*
419 * log_packet - format a packet and log it.
420 */
421
422void
423log_packet(p, len, prefix, level)
424    u_char *p;
425    int len;
426    char *prefix;
427    int level;
428{
429	init_pr_log(prefix, level);
430	format_packet(p, len, pr_log, &level);
431	end_pr_log();
432}
433#endif /* unused */
434
435/*
436 * format_packet - make a readable representation of a packet,
437 * calling `printer(arg, format, ...)' to output it.
438 */
439static void
440format_packet(p, len, printer, arg)
441    u_char *p;
442    int len;
443    void (*printer) __P((void *, char *, ...));
444    void *arg;
445{
446    int i, n;
447    u_short proto;
448    struct protent *protp;
449
450    if (len >= PPP_HDRLEN && p[0] == PPP_ALLSTATIONS && p[1] == PPP_UI) {
451	p += 2;
452	GETSHORT(proto, p);
453	len -= PPP_HDRLEN;
454	for (i = 0; (protp = protocols[i]) != NULL; ++i)
455	    if (proto == protp->protocol)
456		break;
457	if (protp != NULL) {
458	    printer(arg, "[%s", protp->name);
459	    n = (*protp->printpkt)(p, len, printer, arg);
460	    printer(arg, "]");
461	    p += n;
462	    len -= n;
463	} else {
464	    for (i = 0; (protp = protocols[i]) != NULL; ++i)
465		if (proto == (protp->protocol & ~0x8000))
466		    break;
467	    if (protp != 0 && protp->data_name != 0) {
468		printer(arg, "[%s data]", protp->data_name);
469		if (len > 8)
470		    printer(arg, "%.8B ...", p);
471		else
472		    printer(arg, "%.*B", len, p);
473		len = 0;
474	    } else
475		printer(arg, "[proto=0x%x]", proto);
476	}
477    }
478
479    if (len > 32)
480	printer(arg, "%.32B ...", p);
481    else
482	printer(arg, "%.*B", len, p);
483}
484
485/*
486 * init_pr_log, end_pr_log - initialize and finish use of pr_log.
487 */
488
489static char line[256];		/* line to be logged accumulated here */
490static char *linep;		/* current pointer within line */
491static int llevel;		/* level for logging */
492
493void
494init_pr_log(prefix, level)
495     char *prefix;
496     int level;
497{
498	linep = line;
499	if (prefix != NULL) {
500		strlcpy(line, prefix, sizeof(line));
501		linep = line + strlen(line);
502	}
503	llevel = level;
504}
505
506void
507end_pr_log()
508{
509	if (linep != line) {
510		*linep = 0;
511		log_write(llevel, line);
512	}
513}
514
515/*
516 * pr_log - printer routine for outputting to syslog
517 */
518void
519pr_log __V((void *arg, char *fmt, ...))
520{
521	int l, n;
522	va_list pvar;
523	char *p, *eol;
524	char buf[256];
525
526#if defined(__STDC__)
527	va_start(pvar, fmt);
528#else
529	void *arg;
530	char *fmt;
531	va_start(pvar);
532	arg = va_arg(pvar, void *);
533	fmt = va_arg(pvar, char *);
534#endif
535
536	n = vslprintf(buf, sizeof(buf), fmt, pvar);
537	va_end(pvar);
538
539	p = buf;
540	eol = strchr(buf, '\n');
541	if (linep != line) {
542		l = (eol == NULL)? n: eol - buf;
543		if (linep + l < line + sizeof(line)) {
544			if (l > 0) {
545				memcpy(linep, buf, l);
546				linep += l;
547			}
548			if (eol == NULL)
549				return;
550			p = eol + 1;
551			eol = strchr(p, '\n');
552		}
553		*linep = 0;
554		log_write(llevel, line);
555		linep = line;
556	}
557
558	while (eol != NULL) {
559		*eol = 0;
560		log_write(llevel, p);
561		p = eol + 1;
562		eol = strchr(p, '\n');
563	}
564
565	/* assumes sizeof(buf) <= sizeof(line) */
566	l = buf + n - p;
567	if (l > 0) {
568		memcpy(line, p, n);
569		linep = line + l;
570	}
571}
572
573/*
574 * print_string - print a readable representation of a string using
575 * printer.
576 */
577void
578print_string(p, len, printer, arg)
579    char *p;
580    int len;
581    void (*printer) __P((void *, char *, ...));
582    void *arg;
583{
584    int c;
585
586    printer(arg, "\"");
587    for (; len > 0; --len) {
588	c = *p++;
589	if (' ' <= c && c <= '~') {
590	    if (c == '\\' || c == '"')
591		printer(arg, "\\");
592	    printer(arg, "%c", c);
593	} else {
594	    switch (c) {
595	    case '\n':
596		printer(arg, "\\n");
597		break;
598	    case '\r':
599		printer(arg, "\\r");
600		break;
601	    case '\t':
602		printer(arg, "\\t");
603		break;
604	    default:
605		printer(arg, "\\%.3o", c);
606	    }
607	}
608    }
609    printer(arg, "\"");
610}
611
612/*
613 * logit - does the hard work for fatal et al.
614 */
615static void
616logit(level, fmt, args)
617    int level;
618    char *fmt;
619    va_list args;
620{
621    int n;
622    char buf[1024];
623
624    n = vslprintf(buf, sizeof(buf), fmt, args);
625    log_write(level, buf);
626}
627
628static void
629log_write(level, buf)
630    int level;
631    char *buf;
632{
633    syslog(level, "%s", buf);
634    if (log_to_fd >= 0 && (level != LOG_DEBUG || debug)) {
635	int n = strlen(buf);
636
637	if (n > 0 && buf[n-1] == '\n')
638	    --n;
639	if (write(log_to_fd, buf, n) != n
640	    || write(log_to_fd, "\n", 1) != 1)
641	    log_to_fd = -1;
642    }
643}
644
645/*
646 * fatal - log an error message and die horribly.
647 */
648void
649fatal __V((char *fmt, ...))
650{
651    va_list pvar;
652
653#if defined(__STDC__)
654    va_start(pvar, fmt);
655#else
656    char *fmt;
657    va_start(pvar);
658    fmt = va_arg(pvar, char *);
659#endif
660
661    logit(LOG_ERR, fmt, pvar);
662    va_end(pvar);
663
664    die(1);			/* as promised */
665}
666
667/*
668 * error - log an error message.
669 */
670void
671error __V((char *fmt, ...))
672{
673    va_list pvar;
674
675#if defined(__STDC__)
676    va_start(pvar, fmt);
677#else
678    char *fmt;
679    va_start(pvar);
680    fmt = va_arg(pvar, char *);
681#endif
682
683    logit(LOG_ERR, fmt, pvar);
684    va_end(pvar);
685}
686
687/*
688 * warn - log a warning message.
689 */
690void
691warn __V((char *fmt, ...))
692{
693    va_list pvar;
694
695#if defined(__STDC__)
696    va_start(pvar, fmt);
697#else
698    char *fmt;
699    va_start(pvar);
700    fmt = va_arg(pvar, char *);
701#endif
702
703    logit(LOG_WARNING, fmt, pvar);
704    va_end(pvar);
705}
706
707/*
708 * notice - log a notice-level message.
709 */
710void
711notice __V((char *fmt, ...))
712{
713    va_list pvar;
714
715#if defined(__STDC__)
716    va_start(pvar, fmt);
717#else
718    char *fmt;
719    va_start(pvar);
720    fmt = va_arg(pvar, char *);
721#endif
722
723    logit(LOG_NOTICE, fmt, pvar);
724    va_end(pvar);
725}
726
727/*
728 * info - log an informational message.
729 */
730void
731info __V((char *fmt, ...))
732{
733    va_list pvar;
734
735#if defined(__STDC__)
736    va_start(pvar, fmt);
737#else
738    char *fmt;
739    va_start(pvar);
740    fmt = va_arg(pvar, char *);
741#endif
742
743    logit(LOG_INFO, fmt, pvar);
744    va_end(pvar);
745}
746
747/*
748 * dbglog - log a debug message.
749 */
750void
751dbglog __V((char *fmt, ...))
752{
753    va_list pvar;
754
755#if defined(__STDC__)
756    va_start(pvar, fmt);
757#else
758    char *fmt;
759    va_start(pvar);
760    fmt = va_arg(pvar, char *);
761#endif
762
763    logit(LOG_DEBUG, fmt, pvar);
764    va_end(pvar);
765}
766
767/* Procedures for locking the serial device using a lock file. */
768#ifndef LOCK_DIR
769#ifdef _linux_
770#define LOCK_DIR	"/var/lock"
771#else
772#ifdef SVR4
773#define LOCK_DIR	"/var/spool/locks"
774#else
775#define LOCK_DIR	"/var/spool/lock"
776#endif
777#endif
778#endif /* LOCK_DIR */
779
780static char lock_file[MAXPATHLEN];
781
782/*
783 * lock - create a lock file for the named device
784 */
785int
786lock(dev)
787    char *dev;
788{
789#ifdef LOCKLIB
790    int result;
791
792    result = mklock (dev, (void *) 0);
793    if (result == 0) {
794	strlcpy(lock_file, sizeof(lock_file), dev);
795	return 0;
796    }
797
798    if (result > 0)
799        notice("Device %s is locked by pid %d", dev, result);
800    else
801	error("Can't create lock file %s", lock_file);
802    return -1;
803
804#else /* LOCKLIB */
805
806    char lock_buffer[12];
807    int fd, pid, n;
808
809#ifdef SVR4
810    struct stat sbuf;
811
812    if (stat(dev, &sbuf) < 0) {
813	error("Can't get device number for %s: %m", dev);
814	return -1;
815    }
816    if ((sbuf.st_mode & S_IFMT) != S_IFCHR) {
817	error("Can't lock %s: not a character device", dev);
818	return -1;
819    }
820    slprintf(lock_file, sizeof(lock_file), "%s/LK.%03d.%03d.%03d",
821	     LOCK_DIR, major(sbuf.st_dev),
822	     major(sbuf.st_rdev), minor(sbuf.st_rdev));
823#else
824    char *p;
825
826    if ((p = strrchr(dev, '/')) != NULL)
827	dev = p + 1;
828    slprintf(lock_file, sizeof(lock_file), "%s/LCK..%s", LOCK_DIR, dev);
829#endif
830
831    while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {
832	if (errno != EEXIST) {
833	    error("Can't create lock file %s: %m", lock_file);
834	    break;
835	}
836
837	/* Read the lock file to find out who has the device locked. */
838	fd = open(lock_file, O_RDONLY, 0);
839	if (fd < 0) {
840	    if (errno == ENOENT) /* This is just a timing problem. */
841		continue;
842	    error("Can't open existing lock file %s: %m", lock_file);
843	    break;
844	}
845#ifndef LOCK_BINARY
846	n = read(fd, lock_buffer, 11);
847#else
848	n = read(fd, &pid, sizeof(pid));
849#endif /* LOCK_BINARY */
850	close(fd);
851	fd = -1;
852	if (n <= 0) {
853	    error("Can't read pid from lock file %s", lock_file);
854	    break;
855	}
856
857	/* See if the process still exists. */
858#ifndef LOCK_BINARY
859	lock_buffer[n] = 0;
860	pid = atoi(lock_buffer);
861#endif /* LOCK_BINARY */
862	if (pid == getpid())
863	    return 1;		/* somebody else locked it for us */
864	if (pid == 0
865	    || (kill(pid, 0) == -1 && errno == ESRCH)) {
866	    if (unlink (lock_file) == 0) {
867		notice("Removed stale lock on %s (pid %d)", dev, pid);
868		continue;
869	    }
870	    warn("Couldn't remove stale lock on %s", dev);
871	} else
872	    notice("Device %s is locked by pid %d", dev, pid);
873	break;
874    }
875
876    if (fd < 0) {
877	lock_file[0] = 0;
878	return -1;
879    }
880
881    pid = getpid();
882#ifndef LOCK_BINARY
883    slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
884    write (fd, lock_buffer, 11);
885#else
886    write(fd, &pid, sizeof (pid));
887#endif
888    close(fd);
889    return 0;
890
891#endif
892}
893
894/*
895 * relock - called to update our lockfile when we are about to detach,
896 * thus changing our pid (we fork, the child carries on, and the parent dies).
897 * Note that this is called by the parent, with pid equal to the pid
898 * of the child.  This avoids a potential race which would exist if
899 * we had the child rewrite the lockfile (the parent might die first,
900 * and another process could think the lock was stale if it checked
901 * between when the parent died and the child rewrote the lockfile).
902 */
903int
904relock(pid)
905    int pid;
906{
907#ifdef LOCKLIB
908    /* XXX is there a way to do this? */
909    return -1;
910#else /* LOCKLIB */
911
912    int fd;
913    char lock_buffer[12];
914
915    if (lock_file[0] == 0)
916	return -1;
917    fd = open(lock_file, O_WRONLY, 0);
918    if (fd < 0) {
919	error("Couldn't reopen lock file %s: %m", lock_file);
920	lock_file[0] = 0;
921	return -1;
922    }
923
924#ifndef LOCK_BINARY
925    slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
926    write (fd, lock_buffer, 11);
927#else
928    write(fd, &pid, sizeof(pid));
929#endif /* LOCK_BINARY */
930    close(fd);
931    return 0;
932
933#endif /* LOCKLIB */
934}
935
936/*
937 * unlock - remove our lockfile
938 */
939void
940unlock()
941{
942    if (lock_file[0]) {
943#ifdef LOCKLIB
944	(void) rmlock(lock_file, (void *) 0);
945#else
946	unlink(lock_file);
947#endif
948	lock_file[0] = 0;
949    }
950}
951
952