[Midnightbsd-cvs] src [9326] trunk/usr.sbin/syslogd/syslogd.c: syslogd: Use closefrom() instead of getdtablesize()/close()

[laffer1 at midnightbsd.org]

Revision: 9326
          http://svnweb.midnightbsd.org/src/?rev=9326
Author:   laffer1
Date:     2017-03-02 19:23:12 -0500 (Thu, 02 Mar 2017)
Log Message:
-----------
syslogd: Use closefrom() instead of getdtablesize()/close()
loop.

When syslogd forks a process for '|' destinations, it closes all file
descriptors greater than 2.

Use closefrom() for this instead of a getdtablesize()/close() loop because
it is both faster and avoids leaving file descriptors open because the limit
was lowered after they were opened.

Modified Paths:
--------------
    trunk/usr.sbin/syslogd/syslogd.c

Modified: trunk/usr.sbin/syslogd/syslogd.c
===================================================================
--- trunk/usr.sbin/syslogd/syslogd.c	2017-03-03 00:22:38 UTC (rev 9325)
+++ trunk/usr.sbin/syslogd/syslogd.c	2017-03-03 00:23:12 UTC (rev 9326)
@@ -2476,7 +2476,7 @@
 static int
 p_open(const char *prog, pid_t *rpid)
 {
-	int pfd[2], nulldesc, i;
+	int pfd[2], nulldesc;
 	pid_t pid;
 	sigset_t omask, mask;
 	char *argv[4]; /* sh -c cmd NULL */
@@ -2526,8 +2526,7 @@
 		dup2(pfd[0], STDIN_FILENO);
 		dup2(nulldesc, STDOUT_FILENO);
 		dup2(nulldesc, STDERR_FILENO);
-		for (i = getdtablesize(); i > 2; i--)
-			(void)close(i);
+		closefrom(3);
 
 		(void)execvp(_PATH_BSHELL, argv);
 		_exit(255);