From: short <>
Date: Mon, 8 Aug 2005 23:49:12 +0000 (+0000)
Subject: Some updates, still nothing interesting here.
X-Git-Url: http://git.jankratochvil.net/?p=inetdmx.git;a=commitdiff_plain;h=f692db7f13fda5aefb49fcde0caa34f96118e44a

Some updates, still nothing interesting here.
---

diff --git a/inetdmx.c b/inetdmx.c
index e3c4d96..4029438 100644
--- a/inetdmx.c
+++ b/inetdmx.c
@@ -26,6 +26,7 @@ static long opt_start_timeout=60;
 static int opt_port;
 static int opt_syslog;
 static int opt_stderr;
+static const char *opt_lock;
 
 
 /* /usr/include/glib-2.0/glib/gmacros.h */
@@ -89,6 +90,7 @@ static void usage(void)
 {
 	fprintf(stderr,"\
 Syntax: %s [{-T|--start-timeout} <start-timeout] [-S|--syslog] [-e|--stderr]\n\
+        [{-l|--lock} <filename>]\n\
         {-p|--port} <server-port> <start-server-command>\n\
 \n\
 Error messages out to stderr by default, -S|--syslog omits stderr output,\n\
@@ -101,6 +103,7 @@ static const struct option longopts[]={
 	{"start-timeout",1,0,'T'},
 	{"syslog"       ,0,0,'S'},
 	{"stderr"       ,0,0,'e'},
+	{"lock"         ,1,0,'l'},
 	{"port"         ,1,0,'p'},
 	{NULL           ,0,0,0  },
 	};
@@ -232,6 +235,40 @@ int rc;
 			command);
 }
 
+static int lock_fd=-1;
+
+static void lock_create(void)
+{
+int retries=3;
+
+	if (!opt_lock)
+		return;
+retry:
+	if (-1==(lock_fd=open(opt_lock,O_CREAT|O_RDWR,0600)))
+		fatal("Error creating lock file \"%s\": %m",opt_lock);
+	if (flock(lock_fd,LOCK_EX))
+		fatal("Error locking lock file \"%s\": %m",opt_lock);
+	if (!access(opt_lock,O_RD|O_WR)) {
+		if (retries--<=0)
+			fatal("Racing for the lock file \"%s\", giving up");
+		if (close(lock_fd))
+			fatal("Error closing lock file \"%s\": %m",opt_lock);
+		lock_fd=-1;
+		goto retry;
+		}
+	if (utime(opt_lock,NULL))
+		fatal("Error updating lock file \"%s\" timestamp: %m",opt_lock);
+}
+
+static void lock_close(void)
+{
+	if (lock_fd==-1)
+		return;
+	if (close(lock_fd))
+		fatal("Error closing lock file \"%s\": %m",opt_lock);
+	lock_fd=-1;
+}
+
 int main(int argc,char **argv)
 {
 int retry;
@@ -255,6 +292,17 @@ char *endptr;
 			opt_start_timeout=l;
 			break;
 
+		case 'S':	/* -S|--syslog */
+			opt_syslog=1;
+			break;
+
+		case 'e':	/* -e|--stderr */
+			opt_stderr=1;
+			break;
+
+		case 'l':	/* -l|--lock */
+			opt_lock=optarg;
+
 		case 'p':	/* -p|--port */
 			l=strtol(optarg,&endptr,0);
 			if (l<=0 || l>=0x10000 || (endptr && *endptr))
@@ -277,6 +325,7 @@ char *endptr;
 		fatal("Too many arguments, <start-server-command> needs quoting?");
 	command=argv[optind];
 
+	lock_create();
 	session_try();
 	system_checked(command);