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Diffstat (limited to 'i/pc104/initrd/conf/busybox/networking/udhcp/pidfile.c')
-rw-r--r--i/pc104/initrd/conf/busybox/networking/udhcp/pidfile.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/i/pc104/initrd/conf/busybox/networking/udhcp/pidfile.c b/i/pc104/initrd/conf/busybox/networking/udhcp/pidfile.c
new file mode 100644
index 0000000..be65d5f
--- /dev/null
+++ b/i/pc104/initrd/conf/busybox/networking/udhcp/pidfile.c
@@ -0,0 +1,60 @@
+/* vi: set sw=4 ts=4: */
+/* pidfile.c
+ *
+ * Functions to assist in the writing and removing of pidfiles.
+ *
+ * Russ Dill <Russ.Dill@asu.edu> September 2001
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "common.h"
+
+
+static const char *saved_pidfile;
+
+static void pidfile_delete(void)
+{
+ if (saved_pidfile) unlink(saved_pidfile);
+}
+
+
+int pidfile_acquire(const char *pidfile)
+{
+ int pid_fd;
+ if (!pidfile) return -1;
+
+ pid_fd = open(pidfile, O_CREAT|O_WRONLY|O_TRUNC, 0644);
+ if (pid_fd < 0) {
+ bb_perror_msg("cannot open pidfile %s", pidfile);
+ } else {
+ lockf(pid_fd, F_LOCK, 0);
+ if (!saved_pidfile)
+ atexit(pidfile_delete);
+ saved_pidfile = pidfile;
+ }
+
+ return pid_fd;
+}
+
+
+void pidfile_write_release(int pid_fd)
+{
+ if (pid_fd < 0) return;
+
+ fdprintf(pid_fd, "%d\n", getpid());
+ lockf(pid_fd, F_UNLCK, 0);
+ close(pid_fd);
+}