Remove the syslog stuff, and allow various return values
in uu_lock(). Add uu_lockerr() for turning the results of uu_lock into something printable. Remove bogus section in man page about race conditions allowing both processes to get the lock. Include libutil.h and use uu_lock() correctly where it should. Suggested by: ache@freebsd.org
This commit is contained in:
Brian Somers
parent
539f83b7f0
commit
687d0cdeb3
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@ -18,7 +18,7 @@
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* 5. Modifications may be freely made to this file providing the above
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* conditions are met.
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*
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* $Id: libutil.h,v 1.4 1997/02/22 15:08:14 peter Exp $
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* $Id: libutil.h,v 1.5 1997/03/30 12:11:27 brian Exp $
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*/
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#ifndef _LIBUTIL_H_
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@ -41,8 +41,16 @@ int openpty __P((int *amaster, int *aslave, char *name,
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struct termios *termp, struct winsize *winp));
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int forkpty __P((int *amaster, char *name,
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struct termios *termp, struct winsize *winp));
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char *uu_lockerr __P((int uu_lockresult));
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int uu_lock __P((char *ttyname));
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int uu_unlock __P((char *ttyname));
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__END_DECLS
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#define UU_LOCK_INUSE (1)
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#define UU_LOCK_OK (0)
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#define UU_LOCK_OPEN_ERR (-1)
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#define UU_LOCK_READ_ERR (-2)
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#define UU_LOCK_SEEK_ERR (-3)
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#define UU_LOCK_WRITE_ERR (-4)
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#endif /* !_LIBUTIL_H_ */
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@ -23,7 +23,7 @@
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.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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.\"
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.\" $Id$
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.\" $Id: uucplock.3,v 1.1 1997/03/30 12:11:29 brian Exp $
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.\" "
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.Dd March 30, 1997
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.Os
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@ -38,6 +38,8 @@
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.Fn uu_lock "char *ttyname"
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.Ft int
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.Fn uu_unlock "char *ttyname"
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.Ft char *
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.Fn uu_lockerr "int uu_lockresult"
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.Pp
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Link with
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.Va -lutil
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@ -68,23 +70,70 @@ Care should be taken that
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.Fn uu_lock
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was successful before calling
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.Fn uu_unlock .
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.Pp
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.Fn uu_lockerr
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returns an error string representing the error
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.Fa uu_lockresult ,
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as returned from
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.Fn uu_lock .
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.Sh RETURN VALUES
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Both
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.Fn uu_unlock
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returns 0 on success and -1 on failure.
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.Pp
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.Fn uu_lock
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may return any of the following values:
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.Pp
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.Dv UU_LOCK_INUSE:
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The lock is in use by another process.
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.Pp
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.Dv UU_LOCK_OK:
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The lock was successfully created.
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.Pp
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.Dv UU_LOCK_OPEN_ERR:
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The lock file could not be opened via
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.Xr open 2 .
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.Pp
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.Dv UU_LOCK_READ_ERR:
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The lock file could not be read via
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.Xr read 2 .
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.Pp
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.Dv UU_LOCK_SEEK_ERR:
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The lock file was
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.Dq stale ,
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but the call to
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.Xr lseek 2
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necessary to write the current process id failed.
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.Pp
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.Dv UU_LOCK_WRITE_ERR:
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The current process id could not be written to the lock file via a call to
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.Xr write 2 .
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.Pp
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If a value of
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.Dv UU_LOCK_OK
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is passed to
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.Fn uu_lockerr ,
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a
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.Dv NULL
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pointer is returned. If a value of
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.Dv UU_LOCK_INUSE
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is passed, an empty string is returned. Otherwise, a string specifying
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the reason for failure is returned.
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.Fn uu_lockerr
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uses the current value of
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.Dv errno
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to determine the exact error. Care should be made not to allow
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.Dv errno
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to be changed between calls to
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.Fn uu_lock
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and
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.Fn uu_unlock
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return 0 on success and -1 on failure.
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.Fn uu_lockerr .
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.Sh ERRORS
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On failure,
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If
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.Fn uu_lock
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will log any unexpected errors using
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.Xr syslog 2 .
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If the lock already exists and contains the process id of a running
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process,
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.Fn uu_lock
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will silently fail. The value of
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returns one of the four error values above, the global value
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.Dv errno
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can not be used to determine the cause of failure.
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can be used to determine the cause. Refer to the respective manual pages
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for further details.
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.Pp
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.Fn uu_unlock
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will set the global variable
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@ -93,9 +142,23 @@ to reflect the reason that the lock file could not be removed.
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Refer to the description of
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.Xr unlink 2
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for further details.
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.Sh SEE ALSO
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.Xr open 2 ,
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.Xr read 2 ,
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.Xr lseek 2 ,
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.Xr write 2
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.Sh BUGS
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Locking is not atomic. Should a race condition occur, it's entirely
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possible that both processes obtain the lock.
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Locking is not atomic. Should a race condition occur, it's
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possible that the
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.Dq losing
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process fails to identify the
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.Dq winning
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process. If this happens,
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.Fn uu_lock
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returns
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.Dv UU_LOCK_READ_ERR
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and errno is set to
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.Dv EINVAL .
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.Pp
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It is possible that a stale lock is not recognised as such if a new
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processes is assigned the same processes id as the program that left
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@ -47,12 +47,14 @@ static const char sccsid[] = "@(#)uucplock.c 8.1 (Berkeley) 6/6/93";
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#include <stdio.h>
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#include <stdlib.h>
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#include <paths.h>
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#include <string.h>
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#include "libutil.h"
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#define LOCKFMT "LCK..%s"
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/* Forward declarations */
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static int put_pid (int fd, pid_t pid);
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static pid_t get_pid (int fd);
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static pid_t get_pid (int fd,int *err);
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/*
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* uucp style locking routines
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@ -65,6 +67,7 @@ int uu_lock (char *ttyname)
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int fd;
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pid_t pid;
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char tbuf[sizeof(_PATH_UUCPLOCK) + MAXNAMLEN];
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int err;
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(void)sprintf(tbuf, _PATH_UUCPLOCK LOCKFMT, ttyname);
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fd = open(tbuf, O_RDWR|O_CREAT|O_EXCL, 0660);
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@ -74,56 +77,41 @@ int uu_lock (char *ttyname)
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* check to see if the process holding the lock still exists
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*/
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fd = open(tbuf, O_RDWR, 0);
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if (fd < 0) {
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#ifndef USE_PERROR
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syslog(LOG_ERR, "lock open: %m");
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#else
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perror("lock open");
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#endif
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return(-1);
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}
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if ((pid = get_pid (fd)) == -1) {
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#ifndef USE_PERROR
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syslog(LOG_ERR, "lock read: %m");
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#else
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perror("lock read");
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#endif
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if (fd < 0)
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return UU_LOCK_OPEN_ERR;
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if ((pid = get_pid (fd, &err)) == -1) {
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(void)close(fd);
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return(-1);
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errno = err;
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return UU_LOCK_READ_ERR;
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}
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if (kill(pid, 0) == 0 || errno != ESRCH) {
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(void)close(fd); /* process is still running */
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return(-1);
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return UU_LOCK_INUSE;
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}
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/*
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* The process that locked the file isn't running, so
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* we'll lock it ourselves
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*/
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if (lseek(fd, (off_t) 0, L_SET) < 0) {
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#ifndef USE_PERROR
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syslog(LOG_ERR, "lock lseek: %m");
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#else
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perror("lock lseek");
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#endif
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err = errno;
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(void)close(fd);
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return(-1);
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errno = err;
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return UU_LOCK_SEEK_ERR;
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}
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/* fall out and finish the locking process */
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}
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pid = getpid();
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if (!put_pid (fd, pid)) {
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#ifndef USE_PERROR
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syslog(LOG_ERR, "lock write: %m");
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#else
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perror("lock write");
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#endif
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err = errno;
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(void)close(fd);
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(void)unlink(tbuf);
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return(-1);
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errno = err;
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return UU_LOCK_WRITE_ERR;
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}
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(void)close(fd);
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return(0);
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return UU_LOCK_OK;
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}
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int uu_unlock (char *ttyname)
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@ -131,7 +119,43 @@ int uu_unlock (char *ttyname)
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char tbuf[sizeof(_PATH_UUCPLOCK) + MAXNAMLEN];
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(void)sprintf(tbuf, _PATH_UUCPLOCK LOCKFMT, ttyname);
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return(unlink(tbuf));
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return unlink(tbuf);
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}
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char *uu_lockerr (int uu_lockresult)
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{
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static char errbuf[512];
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int len;
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switch (uu_lockresult) {
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case UU_LOCK_INUSE:
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return "";
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case UU_LOCK_OK:
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return 0;
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case UU_LOCK_OPEN_ERR:
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strcpy(errbuf,"open error: ");
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len = 12;
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break;
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case UU_LOCK_READ_ERR:
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strcpy(errbuf,"read error: ");
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len = 12;
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break;
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case UU_LOCK_SEEK_ERR:
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strcpy(errbuf,"seek error: ");
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len = 12;
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break;
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case UU_LOCK_WRITE_ERR:
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strcpy(errbuf,"write error: ");
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len = 13;
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break;
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default:
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strcpy(errbuf,"Undefined error: ");
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len = 17;
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break;
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}
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strncpy(errbuf+len,strerror(errno),sizeof(errbuf)-len-1);
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return errbuf;
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}
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static int put_pid (int fd, pid_t pid)
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@ -143,7 +167,7 @@ static int put_pid (int fd, pid_t pid)
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return write (fd, buf, len) == len;
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}
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static pid_t get_pid (int fd)
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static pid_t get_pid (int fd,int *err)
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{
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int bytes_read;
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char buf[32];
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@ -153,8 +177,10 @@ static pid_t get_pid (int fd)
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if (bytes_read > 0) {
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buf[bytes_read] = '\0';
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pid = strtol (buf, (char **) NULL, 10);
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} else
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} else {
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pid = -1;
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*err = bytes_read ? errno : EINVAL;
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}
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return pid;
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}
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|
|
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|||
|
|
@ -42,7 +42,7 @@ static char copyright[] =
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#ifndef lint
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/*static char sccsid[] = "from: @(#)slattach.c 4.6 (Berkeley) 6/1/90";*/
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static char rcsid[] = "$Id: slattach.c,v 1.25 1997/02/22 14:33:19 peter Exp $";
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||||
static char rcsid[] = "$Id: slattach.c,v 1.26 1997/03/29 03:33:07 imp Exp $";
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||||
#endif /* not lint */
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||||
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||||
#include <sys/param.h>
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||||
|
|
@ -61,6 +61,7 @@ static char rcsid[] = "$Id: slattach.c,v 1.25 1997/02/22 14:33:19 peter Exp $";
|
|||
#include <syslog.h>
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#include <termios.h>
|
||||
#include <unistd.h>
|
||||
#include <libutil.h>
|
||||
|
||||
#include <netinet/in.h>
|
||||
#include <net/if.h>
|
||||
|
|
@ -294,7 +295,10 @@ void acquire_line()
|
|||
|
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if (uucp_lock) {
|
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/* unlock not needed here, always re-lock with new pid */
|
||||
if (uu_lock(dvname)) {
|
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int res;
|
||||
if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
|
||||
if (res != UU_LOCK_INUSE)
|
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syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
|
||||
syslog(LOG_ERR, "can't lock %s", dev);
|
||||
exit_handler(1);
|
||||
}
|
||||
|
|
@ -474,7 +478,10 @@ again:
|
|||
if (system(redial_cmd))
|
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goto again;
|
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if (uucp_lock) {
|
||||
if (uu_lock(dvname)) {
|
||||
int res;
|
||||
if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
|
||||
if (res != UU_LOCK_INUSE)
|
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syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
|
||||
syslog(LOG_ERR, "can't relock %s after %s, aborting",
|
||||
dev, redial_cmd);
|
||||
exit_handler(1);
|
||||
|
|
|
|||
|
|
@ -30,7 +30,7 @@
|
|||
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
*
|
||||
* $Id: startslip.c,v 1.22 1997/02/22 14:33:20 peter Exp $
|
||||
* $Id: startslip.c,v 1.23 1997/03/29 03:33:08 imp Exp $
|
||||
*/
|
||||
|
||||
#ifndef lint
|
||||
|
|
@ -60,6 +60,7 @@ static char sccsid[] = "@(#)startslip.c 8.1 (Berkeley) 6/5/93";
|
|||
#include <termios.h>
|
||||
#include <time.h>
|
||||
#include <unistd.h>
|
||||
#include <libutil.h>
|
||||
|
||||
#include <netinet/in.h>
|
||||
#include <net/if.h>
|
||||
|
|
@ -289,7 +290,10 @@ restart:
|
|||
}
|
||||
printd("open");
|
||||
if (uucp_lock) {
|
||||
if (uu_lock(dvname)) {
|
||||
int res;
|
||||
if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
|
||||
if (res != UU_LOCK_INUSE)
|
||||
syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
|
||||
syslog(LOG_ERR, "%s: can't lock %s", username, devicename);
|
||||
goto restart;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -14,7 +14,6 @@ LIBACU=${.CURDIR}/../libacu/libacu.a
|
|||
.endif
|
||||
|
||||
PROG= tip
|
||||
CFLAGS+=-DUSE_PERROR
|
||||
DPADD= $(LIBACU)
|
||||
LDADD= $(LIBACU) -lutil
|
||||
LINKS= ${BINDIR}/tip
|
||||
|
|
|
|||
|
|
@ -35,6 +35,7 @@
|
|||
static char sccsid[] = "@(#)hunt.c 8.1 (Berkeley) 6/6/93";
|
||||
#endif /* not lint */
|
||||
|
||||
#include <libutil.h>
|
||||
#include "tipconf.h"
|
||||
#include "tip.h"
|
||||
|
||||
|
|
@ -56,13 +57,17 @@ hunt(name)
|
|||
{
|
||||
register char *cp;
|
||||
sig_t f;
|
||||
int res;
|
||||
|
||||
f = signal(SIGALRM, dead);
|
||||
while (cp = getremote(name)) {
|
||||
deadfl = 0;
|
||||
uucplock = rindex(cp, '/')+1;
|
||||
if (uu_lock(uucplock) < 0)
|
||||
if ((res = uu_lock(uucplock)) != UU_LOCK_OK) {
|
||||
if (res != UU_LOCK_INUSE)
|
||||
fprintf(stderr, "uu_lock: %s\n", uu_lockerr(res));
|
||||
continue;
|
||||
}
|
||||
/*
|
||||
* Straight through call units, such as the BIZCOMP,
|
||||
* VADIC and the DF, must indicate they're hardwired in
|
||||
|
|
|
|||
|
|
@ -1,4 +1,4 @@
|
|||
# $Id: Makefile,v 1.16 1997/03/13 12:45:26 brian Exp $
|
||||
# $Id: Makefile,v 1.17 1997/03/30 12:12:20 brian Exp $
|
||||
|
||||
PROG= ppp
|
||||
SRCS= async.c auth.c ccp.c chap.c chat.c command.c filter.c fsm.c hdlc.c \
|
||||
|
|
@ -7,7 +7,7 @@ SRCS= async.c auth.c ccp.c chap.c chat.c command.c filter.c fsm.c hdlc.c \
|
|||
vjcomp.c arp.c alias.c alias_db.c alias_ftp.c alias_util.c \
|
||||
passwdauth.c sig.c
|
||||
#CFLAGS+= -DHAVE_SHELL_CMD_WITH_ANY_MODE
|
||||
CFLAGS += -Wall -DUSE_PERROR -DMSEXT -DPASSWDAUTH
|
||||
CFLAGS += -Wall -DMSEXT -DPASSWDAUTH
|
||||
LDADD += -lmd -lcrypt -lutil
|
||||
DPADD += ${LIBMD} ${LIBCRYPT} ${LIBUTIL}
|
||||
MAN8= ppp.8
|
||||
|
|
|
|||
|
|
@ -17,7 +17,7 @@
|
|||
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
||||
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
||||
*
|
||||
* $Id: modem.c,v 1.30 1997/03/10 06:21:02 ache Exp $
|
||||
* $Id: modem.c,v 1.31 1997/03/10 06:54:58 ache Exp $
|
||||
*
|
||||
* TODO:
|
||||
*/
|
||||
|
|
@ -28,6 +28,7 @@
|
|||
#include <sys/tty.h>
|
||||
#include <errno.h>
|
||||
#include <time.h>
|
||||
#include <libutil.h>
|
||||
#include "hdlc.h"
|
||||
#include "lcp.h"
|
||||
#include "ip.h"
|
||||
|
|
@ -48,7 +49,6 @@ static int connect_count;
|
|||
static struct pppTimer ModemTimer;
|
||||
static char uucplock[10];
|
||||
|
||||
extern int uu_lock(), uu_unlock();
|
||||
extern void PacketMode(), TtyTermMode(), TtyCommandMode();
|
||||
extern int TermMode;
|
||||
|
||||
|
|
@ -377,6 +377,7 @@ int mode;
|
|||
struct termios rstio;
|
||||
int oldflag;
|
||||
char *host, *cp, *port;
|
||||
int res;
|
||||
|
||||
mbits = 0;
|
||||
if (mode & MODE_DIRECT) {
|
||||
|
|
@ -392,8 +393,12 @@ int mode;
|
|||
if (strncmp(VarDevice, "/dev", 4) == 0) {
|
||||
strncpy(uucplock, rindex(VarDevice, '/')+1,sizeof(uucplock)-1);
|
||||
uucplock[sizeof(uucplock)-1] = '\0';
|
||||
if (uu_lock(uucplock) < 0) {
|
||||
LogPrintf(LOG_PHASE_BIT, "Modem %s is in use\n", VarDevice);
|
||||
if ((res = uu_lock(uucplock)) != UU_LOCK_OK) {
|
||||
if (res == UU_LOCK_INUSE)
|
||||
LogPrintf(LOG_PHASE_BIT, "Modem %s is in use\n", VarDevice);
|
||||
else
|
||||
LogPrintf(LOG_PHASE_BIT, "Modem %s is in use: uu_lock: %s\n",
|
||||
VarDevice, uu_lockerr(res));
|
||||
return(-1);
|
||||
}
|
||||
modem = open(VarDevice, O_RDWR|O_NONBLOCK);
|
||||
|
|
|
|||
Loading…
Reference in New Issue