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authorJoel Sherrill <joel.sherrill@OARcorp.com>2001-08-16 20:42:09 +0000
committerJoel Sherrill <joel.sherrill@OARcorp.com>2001-08-16 20:42:09 +0000
commit2f1b9304ac4ba89a2dcb6047cb584a5603a33987 (patch)
treef2339e3f2230b73ee4818d55d4154795e712d803 /cpukit/pppd/utils.c
parent4b3c197fc0912a22b07affd7caef344ce301840a (diff)
downloadrtems-2f1b9304ac4ba89a2dcb6047cb584a5603a33987.tar.bz2
2001-08-16 Mike Siers <mikes@poliac.com>
* Update of PPPD to 2.3.11 from 2.3.5 and addition of an example application. Mike's notes on the modifications: - renamed error() function because of namespace problems - removed calls to the exit() funciton - removed extra files from the pppd source directory - defined pppd task constant values in rtemspppd.h - modifyied example code to get actual tick per second value - placed the pppd 2.3.11 man page file (pppd.8) into the pppd directory * pppd/cbcp.c, pppd/cbcp.h, pppd/main.c, pppd/ppp_tty.c, pppd/pppmain.c, pppd/rtems-ppp.c, pppd/rtems-ppp.c: Deleted. * pppd/pppd.8, pppd/rtemsmain.c, pppd/rtemspppd.c, pppd/rtemspppd.h, pppd/sys-rtems.c, pppd/utils.c, pppd/example/Makefile, pppd/example/README, pppd/example/init.c, pppd/example/netconfig.h, pppd/example/ppp.conf, pppd/example/pppdapp.c, pppd/example/system.h: New files. * modem/ppp_tty.c, net/if_ppp.h, pppd/Makefile.am, pppd/README, pppd/STATUS, pppd/auth.c, pppd/ccp.c, pppd/ccp.h, pppd/chap.c, pppd/chap.h, pppd/chap_ms.c, pppd/chap_ms.h, pppd/chat.c, pppd/demand.c, pppd/fsm.c, pppd/fsm.h, pppd/ipcp.c, pppd/ipcp.h, pppd/ipxcp.c, pppd/ipxcp.h, pppd/lcp.c, pppd/lcp.h, pppd/magic.c, pppd/magic.h, pppd/options.c, pppd/patchlevel.h, pppd/pathnames.h, pppd/pppd.h, pppd/upap.c, pppd/upap.h: Modified.
Diffstat (limited to '')
-rw-r--r--cpukit/pppd/utils.c872
1 files changed, 872 insertions, 0 deletions
diff --git a/cpukit/pppd/utils.c b/cpukit/pppd/utils.c
new file mode 100644
index 0000000000..b1bdb5d754
--- /dev/null
+++ b/cpukit/pppd/utils.c
@@ -0,0 +1,872 @@
+/*
+ * utils.c - various utility functions used in pppd.
+ *
+ * Copyright (c) 1999 The Australian National University.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the Australian National University. The name of the University
+ * may not be used to endorse or promote products derived from this
+ * software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#define RCSID "$Id$"
+
+#include <stdio.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <signal.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <syslog.h>
+#include <pwd.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#ifdef SVR4
+#include <sys/mkdev.h>
+#endif
+
+#include "pppd.h"
+
+static const char rcsid[] = RCSID;
+
+#if defined(SUNOS4)
+extern char *strerror();
+#endif
+
+static void pr_log __P((void *, char *, ...));
+static void logit __P((int, char *, va_list));
+static void vslp_printer __P((void *, char *, ...));
+static void format_packet __P((u_char *, int, void (*) (void *, char *, ...),
+ void *));
+
+struct buffer_info {
+ char *ptr;
+ int len;
+};
+
+/*
+ * strlcpy - like strcpy/strncpy, doesn't overflow destination buffer,
+ * always leaves destination null-terminated (for len > 0).
+ */
+size_t
+strlcpy(dest, src, len)
+ char *dest;
+ const char *src;
+ size_t len;
+{
+ size_t ret = strlen(src);
+
+ if (len != 0) {
+ if (ret < len)
+ strcpy(dest, src);
+ else {
+ strncpy(dest, src, len - 1);
+ dest[len-1] = 0;
+ }
+ }
+ return ret;
+}
+
+/*
+ * strlcat - like strcat/strncat, doesn't overflow destination buffer,
+ * always leaves destination null-terminated (for len > 0).
+ */
+size_t
+strlcat(dest, src, len)
+ char *dest;
+ const char *src;
+ size_t len;
+{
+ size_t dlen = strlen(dest);
+
+ return dlen + strlcpy(dest + dlen, src, (len > dlen? len - dlen: 0));
+}
+
+
+/*
+ * slprintf - format a message into a buffer. Like sprintf except we
+ * also specify the length of the output buffer, and we handle
+ * %r (recursive format), %m (error message), %v (visible string),
+ * %q (quoted string), %t (current time) and %I (IP address) formats.
+ * Doesn't do floating-point formats.
+ * Returns the number of chars put into buf.
+ */
+int
+slprintf __V((char *buf, int buflen, char *fmt, ...))
+{
+ va_list args;
+ int n;
+
+#if defined(__STDC__)
+ va_start(args, fmt);
+#else
+ char *buf;
+ int buflen;
+ char *fmt;
+ va_start(args);
+ buf = va_arg(args, char *);
+ buflen = va_arg(args, int);
+ fmt = va_arg(args, char *);
+#endif
+ n = vslprintf(buf, buflen, fmt, args);
+ va_end(args);
+ return n;
+}
+
+/*
+ * vslprintf - like slprintf, takes a va_list instead of a list of args.
+ */
+#define OUTCHAR(c) (buflen > 0? (--buflen, *buf++ = (c)): 0)
+
+int
+vslprintf(buf, buflen, fmt, args)
+ char *buf;
+ int buflen;
+ char *fmt;
+ va_list args;
+{
+ int c, i, n;
+ int width, prec, fillch;
+ int base, len, neg, quoted;
+ unsigned long val = 0;
+ char *str, *f, *buf0;
+ unsigned char *p;
+ char num[32];
+ time_t t;
+ u_int32_t ip;
+ static char hexchars[] = "0123456789abcdef";
+ struct buffer_info bufinfo;
+
+ buf0 = buf;
+ --buflen;
+ while (buflen > 0) {
+ for (f = fmt; *f != '%' && *f != 0; ++f)
+ ;
+ if (f > fmt) {
+ len = f - fmt;
+ if (len > buflen)
+ len = buflen;
+ memcpy(buf, fmt, len);
+ buf += len;
+ buflen -= len;
+ fmt = f;
+ }
+ if (*fmt == 0)
+ break;
+ c = *++fmt;
+ width = 0;
+ prec = -1;
+ fillch = ' ';
+ if (c == '0') {
+ fillch = '0';
+ c = *++fmt;
+ }
+ if (c == '*') {
+ width = va_arg(args, int);
+ c = *++fmt;
+ } else {
+ while (isdigit(c)) {
+ width = width * 10 + c - '0';
+ c = *++fmt;
+ }
+ }
+ if (c == '.') {
+ c = *++fmt;
+ if (c == '*') {
+ prec = va_arg(args, int);
+ c = *++fmt;
+ } else {
+ prec = 0;
+ while (isdigit(c)) {
+ prec = prec * 10 + c - '0';
+ c = *++fmt;
+ }
+ }
+ }
+ str = 0;
+ base = 0;
+ neg = 0;
+ ++fmt;
+ switch (c) {
+ case 'd':
+ i = va_arg(args, int);
+ if (i < 0) {
+ neg = 1;
+ val = -i;
+ } else
+ val = i;
+ base = 10;
+ break;
+ case 'o':
+ val = va_arg(args, unsigned int);
+ base = 8;
+ break;
+ case 'x':
+ case 'X':
+ val = va_arg(args, unsigned int);
+ base = 16;
+ break;
+ case 'p':
+ val = (unsigned long) va_arg(args, void *);
+ base = 16;
+ neg = 2;
+ break;
+ case 's':
+ str = va_arg(args, char *);
+ break;
+ case 'c':
+ num[0] = va_arg(args, int);
+ num[1] = 0;
+ str = num;
+ break;
+ case 'm':
+ str = strerror(errno);
+ break;
+ case 'I':
+ ip = va_arg(args, u_int32_t);
+ ip = ntohl(ip);
+ slprintf(num, sizeof(num), "%d.%d.%d.%d", (ip >> 24) & 0xff,
+ (ip >> 16) & 0xff, (ip >> 8) & 0xff, ip & 0xff);
+ str = num;
+ break;
+ case 'r':
+ f = va_arg(args, char *);
+#ifndef __powerpc__
+ n = vslprintf(buf, buflen + 1, f, va_arg(args, va_list));
+#else
+ /* On the powerpc, a va_list is an array of 1 structure */
+ n = vslprintf(buf, buflen + 1, f, va_arg(args, void *));
+#endif
+ buf += n;
+ buflen -= n;
+ continue;
+ case 't':
+ time(&t);
+ str = ctime(&t);
+ str += 4; /* chop off the day name */
+ str[15] = 0; /* chop off year and newline */
+ break;
+ case 'v': /* "visible" string */
+ case 'q': /* quoted string */
+ quoted = c == 'q';
+ p = va_arg(args, unsigned char *);
+ if (fillch == '0' && prec >= 0) {
+ n = prec;
+ } else {
+ n = strlen((char *)p);
+ if (prec >= 0 && n > prec)
+ n = prec;
+ }
+ while (n > 0 && buflen > 0) {
+ c = *p++;
+ --n;
+ if (!quoted && c >= 0x80) {
+ OUTCHAR('M');
+ OUTCHAR('-');
+ c -= 0x80;
+ }
+ if (quoted && (c == '"' || c == '\\'))
+ OUTCHAR('\\');
+ if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
+ if (quoted) {
+ OUTCHAR('\\');
+ switch (c) {
+ case '\t': OUTCHAR('t'); break;
+ case '\n': OUTCHAR('n'); break;
+ case '\b': OUTCHAR('b'); break;
+ case '\f': OUTCHAR('f'); break;
+ default:
+ OUTCHAR('x');
+ OUTCHAR(hexchars[c >> 4]);
+ OUTCHAR(hexchars[c & 0xf]);
+ }
+ } else {
+ if (c == '\t')
+ OUTCHAR(c);
+ else {
+ OUTCHAR('^');
+ OUTCHAR(c ^ 0x40);
+ }
+ }
+ } else
+ OUTCHAR(c);
+ }
+ continue;
+ case 'P': /* print PPP packet */
+ bufinfo.ptr = buf;
+ bufinfo.len = buflen + 1;
+ p = va_arg(args, unsigned char *);
+ n = va_arg(args, int);
+ format_packet(p, n, vslp_printer, &bufinfo);
+ buf = bufinfo.ptr;
+ buflen = bufinfo.len - 1;
+ continue;
+ case 'B':
+ p = va_arg(args, unsigned char *);
+ for (n = prec; n > 0; --n) {
+ c = *p++;
+ if (fillch == ' ')
+ OUTCHAR(' ');
+ OUTCHAR(hexchars[(c >> 4) & 0xf]);
+ OUTCHAR(hexchars[c & 0xf]);
+ }
+ continue;
+ default:
+ *buf++ = '%';
+ if (c != '%')
+ --fmt; /* so %z outputs %z etc. */
+ --buflen;
+ continue;
+ }
+ if (base != 0) {
+ str = num + sizeof(num);
+ *--str = 0;
+ while (str > num + neg) {
+ *--str = hexchars[val % base];
+ val = val / base;
+ if (--prec <= 0 && val == 0)
+ break;
+ }
+ switch (neg) {
+ case 1:
+ *--str = '-';
+ break;
+ case 2:
+ *--str = 'x';
+ *--str = '0';
+ break;
+ }
+ len = num + sizeof(num) - 1 - str;
+ } else {
+ len = strlen(str);
+ if (prec >= 0 && len > prec)
+ len = prec;
+ }
+ if (width > 0) {
+ if (width > buflen)
+ width = buflen;
+ if ((n = width - len) > 0) {
+ buflen -= n;
+ for (; n > 0; --n)
+ *buf++ = fillch;
+ }
+ }
+ if (len > buflen)
+ len = buflen;
+ memcpy(buf, str, len);
+ buf += len;
+ buflen -= len;
+ }
+ *buf = 0;
+ return buf - buf0;
+}
+
+/*
+ * vslp_printer - used in processing a %P format
+ */
+static void
+vslp_printer __V((void *arg, char *fmt, ...))
+{
+ int n;
+ va_list pvar;
+ struct buffer_info *bi;
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ void *arg;
+ char *fmt;
+ va_start(pvar);
+ arg = va_arg(pvar, void *);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ bi = (struct buffer_info *) arg;
+ n = vslprintf(bi->ptr, bi->len, fmt, pvar);
+ va_end(pvar);
+
+ bi->ptr += n;
+ bi->len -= n;
+}
+
+/*
+ * log_packet - format a packet and log it.
+ */
+
+char line[256]; /* line to be logged accumulated here */
+char *linep;
+
+void
+log_packet(p, len, prefix, level)
+ u_char *p;
+ int len;
+ char *prefix;
+ int level;
+{
+ strlcpy(line, prefix, sizeof(line));
+ linep = line + strlen(line);
+ format_packet(p, len, pr_log, NULL);
+}
+
+/*
+ * format_packet - make a readable representation of a packet,
+ * calling `printer(arg, format, ...)' to output it.
+ */
+static void
+format_packet(p, len, printer, arg)
+ u_char *p;
+ int len;
+ void (*printer) __P((void *, char *, ...));
+ void *arg;
+{
+ int i, n;
+ u_short proto;
+ struct protent *protp;
+
+ if (len >= PPP_HDRLEN && p[0] == PPP_ALLSTATIONS && p[1] == PPP_UI) {
+ p += 2;
+ GETSHORT(proto, p);
+ len -= PPP_HDRLEN;
+ for (i = 0; (protp = protocols[i]) != NULL; ++i)
+ if (proto == protp->protocol)
+ break;
+ if (protp != NULL) {
+ printer(arg, "[%s", protp->name);
+ n = (*protp->printpkt)(p, len, printer, arg);
+ printer(arg, "]");
+ p += n;
+ len -= n;
+ } else {
+ for (i = 0; (protp = protocols[i]) != NULL; ++i)
+ if (proto == (protp->protocol & ~0x8000))
+ break;
+ if (protp != 0 && protp->data_name != 0) {
+ printer(arg, "[%s data]", protp->data_name);
+ if (len > 8)
+ printer(arg, "%.8B ...", p);
+ else
+ printer(arg, "%.*B", len, p);
+ len = 0;
+ } else
+ printer(arg, "[proto=0x%x]", proto);
+ }
+ }
+
+ if (len > 32)
+ printer(arg, "%.32B ...", p);
+ else
+ printer(arg, "%.*B", len, p);
+}
+
+static void
+pr_log __V((void *arg, char *fmt, ...))
+{
+ int n;
+ va_list pvar;
+ char buf[256];
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ void *arg;
+ char *fmt;
+ va_start(pvar);
+ arg = va_arg(pvar, void *);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ n = vslprintf(buf, sizeof(buf), fmt, pvar);
+ va_end(pvar);
+
+ if (linep + n + 1 > line + sizeof(line)) {
+ linep = line;
+ }
+ strlcpy(linep, buf, line + sizeof(line) - linep);
+ linep += n;
+}
+
+/*
+ * print_string - print a readable representation of a string using
+ * printer.
+ */
+void
+print_string(p, len, printer, arg)
+ char *p;
+ int len;
+ void (*printer) __P((void *, char *, ...));
+ void *arg;
+{
+ int c;
+
+ printer(arg, "\"");
+ for (; len > 0; --len) {
+ c = *p++;
+ if (' ' <= c && c <= '~') {
+ if (c == '\\' || c == '"')
+ printer(arg, "\\");
+ printer(arg, "%c", c);
+ } else {
+ switch (c) {
+ case '\n':
+ printer(arg, "\\n");
+ break;
+ case '\r':
+ printer(arg, "\\r");
+ break;
+ case '\t':
+ printer(arg, "\\t");
+ break;
+ default:
+ printer(arg, "\\%.3o", c);
+ }
+ }
+ }
+ printer(arg, "\"");
+}
+
+/*
+ * logit - does the hard work for fatal et al.
+ */
+static void
+logit(level, fmt, args)
+ int level;
+ char *fmt;
+ va_list args;
+{
+ int n;
+ char buf[256];
+
+ n = vslprintf(buf, sizeof(buf), fmt, args);
+/* if (log_to_fd >= 0 && (level != LOG_DEBUG || debug)) { */
+ if (log_to_fd >= 0 && (debug)) {
+ if (buf[n-1] != '\n')
+ buf[n++] = '\n';
+ if (write(log_to_fd, buf, n) != n)
+ log_to_fd = -1;
+ }
+}
+
+/*
+ * fatal - log an error message and die horribly.
+ */
+void
+pppd_fatal __V((char *fmt, ...))
+{
+ va_list pvar;
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ char *fmt;
+ va_start(pvar);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ logit(LOG_ERR, fmt, pvar);
+ va_end(pvar);
+
+ die(1); /* as promised */
+}
+
+/*
+ * error - log an error message.
+ */
+void
+pppd_error __V((char *fmt, ...))
+{
+ va_list pvar;
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ char *fmt;
+ va_start(pvar);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ logit(LOG_ERR, fmt, pvar);
+ va_end(pvar);
+}
+
+/*
+ * warn - log a warning message.
+ */
+void
+pppd_warn __V((char *fmt, ...))
+{
+ va_list pvar;
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ char *fmt;
+ va_start(pvar);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ logit(LOG_WARNING, fmt, pvar);
+ va_end(pvar);
+}
+
+/*
+ * notice - log a notice-level message.
+ */
+void
+pppd_notice __V((char *fmt, ...))
+{
+ va_list pvar;
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ char *fmt;
+ va_start(pvar);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ logit(LOG_NOTICE, fmt, pvar);
+ va_end(pvar);
+}
+
+/*
+ * info - log an informational message.
+ */
+void
+pppd_info __V((char *fmt, ...))
+{
+ va_list pvar;
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ char *fmt;
+ va_start(pvar);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ logit(LOG_INFO, fmt, pvar);
+ va_end(pvar);
+}
+
+/*
+ * dbglog - log a debug message.
+ */
+void
+pppd_dbglog __V((char *fmt, ...))
+{
+ va_list pvar;
+
+#if defined(__STDC__)
+ va_start(pvar, fmt);
+#else
+ char *fmt;
+ va_start(pvar);
+ fmt = va_arg(pvar, char *);
+#endif
+
+ logit(LOG_DEBUG, fmt, pvar);
+ va_end(pvar);
+}
+
+/* Procedures for locking the serial device using a lock file. */
+#ifndef LOCK_DIR
+#ifdef _linux_
+#define LOCK_DIR "/var/lock"
+#else
+#ifdef SVR4
+#define LOCK_DIR "/var/spool/locks"
+#else
+#define LOCK_DIR "/var/spool/lock"
+#endif
+#endif
+#endif /* LOCK_DIR */
+
+static char lock_file[MAXPATHLEN];
+
+/*
+ * lock - create a lock file for the named device
+ */
+int
+lock(dev)
+ char *dev;
+{
+#ifdef LOCKLIB
+ int result;
+
+ result = mklock (dev, (void *) 0);
+ if (result == 0) {
+ strlcpy(lock_file, sizeof(lock_file), dev);
+ return 0;
+ }
+
+ if (result > 0)
+ notice("Device %s is locked by pid %d", dev, result);
+ else
+ error("Can't create lock file %s", lock_file);
+ return -1;
+
+#else /* LOCKLIB */
+
+ char lock_buffer[12];
+ int fd, pid, n;
+
+#ifdef SVR4
+ struct stat sbuf;
+
+ if (stat(dev, &sbuf) < 0) {
+ error("Can't get device number for %s: %m", dev);
+ return -1;
+ }
+ if ((sbuf.st_mode & S_IFMT) != S_IFCHR) {
+ error("Can't lock %s: not a character device", dev);
+ return -1;
+ }
+ slprintf(lock_file, sizeof(lock_file), "%s/LK.%03d.%03d.%03d",
+ LOCK_DIR, major(sbuf.st_dev),
+ major(sbuf.st_rdev), minor(sbuf.st_rdev));
+#else
+ char *p;
+
+ if ((p = strrchr(dev, '/')) != NULL)
+ dev = p + 1;
+ slprintf(lock_file, sizeof(lock_file), "%s/LCK..%s", LOCK_DIR, dev);
+#endif
+
+ while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {
+ if (errno != EEXIST) {
+ error("Can't create lock file %s: %m", lock_file);
+ break;
+ }
+
+ /* Read the lock file to find out who has the device locked. */
+ fd = open(lock_file, O_RDONLY, 0);
+ if (fd < 0) {
+ if (errno == ENOENT) /* This is just a timing problem. */
+ continue;
+ error("Can't open existing lock file %s: %m", lock_file);
+ break;
+ }
+#ifndef LOCK_BINARY
+ n = read(fd, lock_buffer, 11);
+#else
+ n = read(fd, &pid, sizeof(pid));
+#endif /* LOCK_BINARY */
+ close(fd);
+ fd = -1;
+ if (n <= 0) {
+ error("Can't read pid from lock file %s", lock_file);
+ break;
+ }
+
+ /* See if the process still exists. */
+#ifndef LOCK_BINARY
+ lock_buffer[n] = 0;
+ pid = atoi(lock_buffer);
+#endif /* LOCK_BINARY */
+ if (pid == getpid())
+ return 1; /* somebody else locked it for us */
+ if (pid == 0
+ || (kill(pid, 0) == -1 && errno == ESRCH)) {
+ if (unlink (lock_file) == 0) {
+ notice("Removed stale lock on %s (pid %d)", dev, pid);
+ continue;
+ }
+ warn("Couldn't remove stale lock on %s", dev);
+ } else
+ notice("Device %s is locked by pid %d", dev, pid);
+ break;
+ }
+
+ if (fd < 0) {
+ lock_file[0] = 0;
+ return -1;
+ }
+
+ pid = getpid();
+#ifndef LOCK_BINARY
+ slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
+ write (fd, lock_buffer, 11);
+#else
+ write(fd, &pid, sizeof (pid));
+#endif
+ close(fd);
+ return 0;
+
+#endif
+}
+
+/*
+ * relock - called to update our lockfile when we are about to detach,
+ * thus changing our pid (we fork, the child carries on, and the parent dies).
+ * Note that this is called by the parent, with pid equal to the pid
+ * of the child. This avoids a potential race which would exist if
+ * we had the child rewrite the lockfile (the parent might die first,
+ * and another process could think the lock was stale if it checked
+ * between when the parent died and the child rewrote the lockfile).
+ */
+int
+relock(pid)
+ int pid;
+{
+#ifdef LOCKLIB
+ /* XXX is there a way to do this? */
+ return -1;
+#else /* LOCKLIB */
+
+ int fd;
+ char lock_buffer[12];
+
+ if (lock_file[0] == 0)
+ return -1;
+ fd = open(lock_file, O_WRONLY, 0);
+ if (fd < 0) {
+ error("Couldn't reopen lock file %s: %m", lock_file);
+ lock_file[0] = 0;
+ return -1;
+ }
+
+#ifndef LOCK_BINARY
+ slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
+ write (fd, lock_buffer, 11);
+#else
+ write(fd, &pid, sizeof(pid));
+#endif /* LOCK_BINARY */
+ close(fd);
+ return 0;
+
+#endif /* LOCKLIB */
+}
+
+/*
+ * unlock - remove our lockfile
+ */
+void
+unlock()
+{
+ if (lock_file[0]) {
+#ifdef LOCKLIB
+ (void) rmlock(lock_file, (void *) 0);
+#else
+ unlink(lock_file);
+#endif
+ lock_file[0] = 0;
+ }
+}
+