Fix jitterbuffer logging not creating logfiles.

Three changes made here:
1) Do not fail if a previous log does not exist (in fact, this is probably
expected).
2) Ensure that the file descriptor to write to gets assigned properly. I am at
a loss as to why assigning safe_fd outside the if fixes this, but it makes
the if statement slightly less complicated anyway.
3) Move up the failure message so that the errno of the failure is not
overwritten by fclose.

(closes issue #16917)
Reported by: Artem


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@251631 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/abstract_jb.c

@@ -498,12 +498,14 @@ static int create_jb(struct ast_channel *chan, struct ast_frame *frr)
 
 		snprintf(logfile_pathname, sizeof(logfile_pathname),
 			"/tmp/ast_%s_jb_%s--%s.log", jbimpl->name, name1, name2);
-		if (!(safe_fd = mkstemp(safe_logfile)) > -1 || unlink(logfile_pathname) || link(safe_logfile, logfile_pathname) || unlink(safe_logfile) || !(jb->logfile = fdopen(safe_fd, "w+b"))) {
+		unlink(logfile_pathname);
+		safe_fd = mkstemp(safe_logfile);
+		if (safe_fd < 0 || link(safe_logfile, logfile_pathname) || unlink(safe_logfile) || !(jb->logfile = fdopen(safe_fd, "w+b"))) {
+			ast_log(LOG_ERROR, "Failed to create frame log file with pathname '%s': %s\n", logfile_pathname, strerror(errno));
 			jb->logfile = NULL;
 			if (safe_fd > -1) {
 				close(safe_fd);
 			}
-			ast_log(LOG_ERROR, "Failed to create frame log file with pathname '%s': %s\n", logfile_pathname, strerror(errno));
 		}
 
 		if (res == JB_IMPL_OK) {