Some prevention of stale locks by unlocking it whenever possible.

[inetdmx.git] / inetdmx.c

diff --git a/inetdmx.c b/inetdmx.c
index 13efc7f..006a4f2 100644 (file)
--- a/inetdmx.c
+++ b/inetdmx.c
@@ -77,6 +77,9 @@ static char *opt_command;
 
 static void fatal(const char *fmt,...) G_GNUC_PRINTF(1,2) G_GNUC_NORETURN;
 
+/* for atexit(3) function */
+static int verror_quiet;
+
 static void verror(const char *fmt,va_list ap) G_GNUC_PRINTF(1,0);
 static void verror(const char *fmt,va_list ap)
 {
@@ -84,6 +87,8 @@ int use_syslog=opt_syslog,use_stderr=opt_stderr;
 char *string;
 const char *const double_error="Error printing error message";
 
+       if (verror_quiet)
+               return;
        if (!use_syslog && !use_stderr)
                use_stderr=1;
        if (-1==vasprintf(&string,fmt,ap)) {
@@ -237,13 +242,25 @@ static void lock_touch(void)
 
 static void lock_close(void)
 {
-       if (lock_fd==-1)
+       if (lock_fd==-1 || !opt_lock)
                return;
+       /* It should not be needed but some stale locks were seen on:
+        *      White Box Linux kernel-smp-2.6.9-5.0.5.EL
+        */
+       if (flock(lock_fd,LOCK_UN|LOCK_NB))
+               fatal("Error unlocking lock file \"%s\": %m",opt_lock);
        if (close(lock_fd))
                fatal("Error closing lock file \"%s\": %m",opt_lock);
        lock_fd=-1;
 }
 
+static void lock_close_atexit(void)
+{
+       /* Prevent some crashes of malloc(3) etc. */
+       verror_quiet=1;
+       lock_close();
+}
+
 static int connect_try(void)
 {
 int fdtcp;
@@ -497,6 +514,8 @@ char *s;
        else
                program_name=argv[0];
 
+       atexit(lock_close_atexit);
+
        optarg=NULL; optind=0;  /* FIXME: Possible portability problem. */
        while ((optc=getopt_long(argc,argv,"01T:i:Sel:p:Ih",longopts,NULL))!=EOF) switch (optc) {
 long l;