Only remove the lock file if we managed to lock it

The lock file was being removed when we hadn't successfully locked
it which defeated the purpose of the lockfile.  Adjust cleanup_lockfile
such that it only unlinks the lockfile if we have successfully locked
the lockfile and it is still active (lockfile != NULL).

(cherry picked from commit b9c789b8b34a45a1572590a9ef4c8aa1306b4c63)

diff --git a/bin/named/os.c b/bin/named/os.c
index 7af47294ba5ae6b0b6e56557a0ea9be1afa494c2..0222abb7c2c68075da94982880f327b17ce01bc7 100644 (file)
--- a/bin/named/os.c
+++ b/bin/named/os.c
@@ -552,17 +552,19 @@ cleanup_pidfile(void) {
 }
 
 static void
-cleanup_lockfile(void) {
+cleanup_lockfile(bool unlink_lockfile) {
        if (singletonfd != -1) {
                close(singletonfd);
                singletonfd = -1;
        }
 
        if (lockfile != NULL) {
-               int n = unlink(lockfile);
-               if (n == -1 && errno != ENOENT) {
-                       named_main_earlywarning("unlink '%s': failed",
-                                               lockfile);
+               if (unlink_lockfile) {
+                       int n = unlink(lockfile);
+                       if (n == -1 && errno != ENOENT) {
+                               named_main_earlywarning("unlink '%s': failed",
+                                                       lockfile);
+                       }
                }
                free(lockfile);
                lockfile = NULL;
@@ -830,7 +832,7 @@ named_os_issingleton(const char *filename) {
                if (ret == -1) {
                        named_main_earlywarning("couldn't create '%s'",
                                                filename);
-                       cleanup_lockfile();
+                       cleanup_lockfile(false);
                        return (false);
                }
        }
@@ -842,7 +844,7 @@ named_os_issingleton(const char *filename) {
        singletonfd = open(filename, O_WRONLY | O_CREAT,
                           S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
        if (singletonfd == -1) {
-               cleanup_lockfile();
+               cleanup_lockfile(false);
                return (false);
        }
 
@@ -854,8 +856,7 @@ named_os_issingleton(const char *filename) {
 
        /* Non-blocking (does not wait for lock) */
        if (fcntl(singletonfd, F_SETLK, &lock) == -1) {
-               close(singletonfd);
-               singletonfd = -1;
+               cleanup_lockfile(false);
                return (false);
        }
 
@@ -866,7 +867,7 @@ void
 named_os_shutdown(void) {
        closelog();
        cleanup_pidfile();
-       cleanup_lockfile();
+       cleanup_lockfile(true);
 }
 
 void