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-rw-r--r--nis/lckcache.c181
1 files changed, 0 insertions, 181 deletions
diff --git a/nis/lckcache.c b/nis/lckcache.c
deleted file mode 100644
index f8c0a97..0000000
--- a/nis/lckcache.c
+++ /dev/null
@@ -1,181 +0,0 @@
-/* Handle locking of NIS+ cache file.
- Copyright (C) 1996, 1997 Free Software Foundation, Inc.
- This file is part of the GNU C Library and based on shadow/lckfile.c.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Library General Public License for more details.
-
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
-
-#include <fcntl.h>
-#include <bits/libc-lock.h>
-#include <shadow.h>
-#include <signal.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/file.h>
-#include <rpcsvc/nis.h>
-#include <rpcsvc/nislib.h>
-#include <rpcsvc/nis_cache.h>
-
-/* How long to wait for getting the lock before returning with an
- error. */
-#define TIMEOUT 5 /* sec */
-
-
-/* File descriptor for lock file. */
-static int lock_fd = -1;
-
-/* Prevent problems in multithreaded program by using mutex. */
-__libc_lock_define_initialized (static, lock)
-
-
-/* Prototypes for local functions. */
-static void noop_handler __P ((int __sig));
-
-
-/* We cannot simply return in error cases. We have to close the file
- and perhaps restore the signal handler. */
-#define RETURN_CLOSE_FD(code) \
- do { \
- if ((code) < 0 && lock_fd >= 0) \
- { \
- close (lock_fd); \
- lock_fd = -1; \
- } \
- __libc_lock_unlock (lock); \
- return (code); \
- } while (0)
-
-#define RETURN_RESTORE_HANDLER(code) \
- do { \
- /* Restore old action handler for alarm. We don't need to know \
- about the current one. */ \
- sigaction (SIGALRM, &saved_act, NULL); \
- RETURN_CLOSE_FD (code); \
- } while (0)
-
-#define RETURN_CLEAR_ALARM(code) \
- do { \
- /* Clear alarm. */ \
- alarm (0); \
- /* Restore old set of handled signals. We don't need to know \
- about the current one.*/ \
- sigprocmask (SIG_SETMASK, &saved_set, NULL); \
- RETURN_RESTORE_HANDLER (code); \
- } while (0)
-
-
-int
-__nis_lock_cache (void)
-{
- int flags;
- sigset_t saved_set; /* Saved set of caught signals. */
- struct sigaction saved_act; /* Saved signal action. */
- sigset_t new_set; /* New set of caught signals. */
- struct sigaction new_act; /* New signal action. */
- struct flock fl; /* Information struct for locking. */
- int result;
-
- if (lock_fd != -1)
- /* Still locked by own process. */
- return -1;
-
- /* Prevent problems caused by multiple threads. */
- __libc_lock_lock (lock);
-
- lock_fd = open (CACHELOCK, O_RDONLY|O_CREAT, 0666);
- if (lock_fd == -1)
- /* Cannot create lock file. */
- RETURN_CLOSE_FD (-1);
-
- /* Make sure file gets correctly closed when process finished. */
- flags = fcntl (lock_fd, F_GETFD, 0);
- if (flags == -1)
- /* Cannot get file flags. */
- RETURN_CLOSE_FD (-1);
- flags |= FD_CLOEXEC; /* Close on exit. */
- if (fcntl (lock_fd, F_SETFD, flags) < 0)
- /* Cannot set new flags. */
- RETURN_CLOSE_FD (-1);
-
- /* Now we have to get exclusive write access. Since multiple
- process could try this we won't stop when it first fails.
- Instead we set a timeout for the system call. Once the timer
- expires it is likely that there are some problems which cannot be
- resolved by waiting.
-
- It is important that we don't change the signal state. We must
- restore the old signal behaviour. */
- memset (&new_act, '\0', sizeof (struct sigaction));
- new_act.sa_handler = noop_handler;
- sigfillset (&new_act.sa_mask);
- new_act.sa_flags = 0ul;
-
- /* Install new action handler for alarm and save old. */
- if (sigaction (SIGALRM, &new_act, &saved_act) < 0)
- /* Cannot install signal handler. */
- RETURN_CLOSE_FD (-1);
-
- /* Now make sure the alarm signal is not blocked. */
- sigemptyset (&new_set);
- sigaddset (&new_set, SIGALRM);
- if (sigprocmask (SIG_UNBLOCK, &new_set, &saved_set) < 0)
- RETURN_RESTORE_HANDLER (-1);
-
- /* Start timer. If we cannot get the lock in the specified time we
- get a signal. */
- alarm (TIMEOUT);
-
- /* Try to get the lock. */
- memset (&fl, '\0', sizeof (struct flock));
- fl.l_type = F_RDLCK;
- fl.l_whence = SEEK_SET;
- result = fcntl (lock_fd, F_SETLKW, &fl);
-
- RETURN_CLEAR_ALARM (result);
-}
-
-
-int
-__nis_unlock_cache ()
-{
- int result;
-
- if (lock_fd == -1)
- /* There is no lock set. */
- result = -1;
- else
- {
- /* Prevent problems caused by multiple threads. */
- __libc_lock_lock (lock);
-
- result = close (lock_fd);
-
- /* Mark descriptor as unused. */
- lock_fd = -1;
-
- /* Clear mutex. */
- __libc_lock_unlock (lock);
- }
-
- return result;
-}
-
-
-static void
-noop_handler (sig)
- int sig;
-{
- /* We simply return which makes the `fcntl' call return with an error. */
-}