safe_asterisk: Don't automatically exceed MAXFILES value of 2^20.

On systems with lots of RAM (e.g. 24GB) /proc/sys/fs/file-max divided
by two can exceed the per-process file limit of 2^20. This patch
ensures the value is capped.

(Patch cleaned up by me.)

ASTERISK-24011 #close
Reported by: Michael Myles
Patches:
  safe_asterisk-ulimit.diff uploaded by Michael Myles (License #6626)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@424875 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -24737,6 +24737,10 @@ static int handle_request_bye(struct sip_pvt *p, struct sip_request *req)
 	} else {
 		transmit_response(p, "200 OK", req);
 	}
+	
+	/* Destroy any pending invites so we won't try to do another
+	 * scheduled reINVITE. */
+	AST_SCHED_DEL_UNREF(sched, p->waitid, dialog_unref(p, "decrement refcount from sip_destroy because waitid won't be scheduled"));
 
 	return 1;
 }

contrib/scripts/safe_asterisk

@@ -63,12 +63,17 @@ if test `id -u` != 0; then
 	message "safe_asterisk was started by `id -n` (uid `id -u`)."
 else
 	if `uname -s | grep Linux >/dev/null 2>&1`; then
-		# maximum number of open files is set to the system maximum divided by two if
-		# MAXFILES is not set.
+		# maximum number of open files is set to the system maximum
+		# divided by two if MAXFILES is not set.
 		if test -z "$MAXFILES"; then
 			# just check if file-max is readable
 			if test -r /proc/sys/fs/file-max; then
-				MAXFILES=$(( `cat /proc/sys/fs/file-max` / 2 ))
+				MAXFILES=$((`cat /proc/sys/fs/file-max` / 2))
+				# don't exceed upper limit of 2^20 for open
+				# files on systems where file-max is > 2^21
+				if test $MAXFILES -gt 1048576; then
+					MAXFILES=1048576
+				fi
 			fi
 		fi
 		SYSCTL_MAXFILES="fs.file-max"