1 files changed, 60 insertions, 0 deletions
diff --git a/smsd/pidfile.c b/smsd/pidfile.c
new file mode 100644
index 0000000..335bec9
--- /dev/null
+++ b/smsd/pidfile.c
@@ -0,0 +1,60 @@
+/**
+ * SMSD PID file handling
+ */
+/* Copyright (c) 2009 Michal Cihar <michal@cihar.com> */
+/* Licensend under GNU GPL 2 */
+
+#include <stdio.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <stdlib.h>
+
+#include "pidfile.h"
+
+/**
+ * Check existing PID file if it points to existing application.
+ */
+void check_pid(const char *pid_file)
+{
+	FILE *file;
+
+	int other;
+
+	file = fopen(pid_file, "r");
+	if (file != NULL) {
+		if (fscanf(file, "%d", &other) == 1) {
+			if (kill(other, 0) == 0) {
+				fprintf(stderr,
+					"Another instance is running, please stop it first!\n");
+				exit(10);
+			} else {
+				fprintf(stderr, "Stale lock file, ignoring!\n");
+			}
+		} else {
+			fprintf(stderr, "Can not parse pidfile, ignoring!\n");
+		}
+		fclose(file);
+	}
+}
+
+/**
+ * Write a pid file.
+ */
+void write_pid(const char *pid_file)
+{
+	FILE *file;
+
+	file = fopen(pid_file, "w");
+	if (file != NULL) {
+		fprintf(file, "%d\n", getpid());
+		fclose(file);
+	} else {
+		fprintf(stderr, "Can not create pidfile!\n");
+		exit(1);
+	}
+}
+
+/* How should editor hadle tabs in this file? Add editor commands here.
+ * vim: noexpandtab sw=8 ts=8 sts=8:
+ */