* Don't SEGFAULT on attempt to write nothing (if no source files were

specified)
* Don't print currline if it's NULL

MFC after: 3 days

1 files changed, 4 insertions, 1 deletions

diff --git a/usr.bin/gencat/genlib.c b/usr.bin/gencat/genlib.c
index e1a55bfbc66c..185f2a029cbf 100644
--- a/usr.bin/gencat/genlib.c
+++ b/usr.bin/gencat/genlib.c
@@ -49,7 +49,7 @@ static long lineno = 0;
 static void
 warning(char *cptr, const char *msg)
 {
-    warnx("%s on line %ld\n%s", msg, lineno, curline);
+    warnx("%s on line %ld\n%s", msg, lineno, (curline == NULL ? "" : curline) );
     if (cptr) {
 	char	*tptr;
 	for (tptr = curline; tptr < cptr; ++tptr) putc(' ', stderr);
@@ -559,6 +559,9 @@ MCWriteCat(int fd)
     mcHead.flags = MCGetByteOrder();
     mcHead.firstSet = 0;	/* We'll be back to set this in a minute */
 
+    if (cat == NULL)
+	error(NULL, "cannot write empty catalog set");
+
     for (cnt = 0, set = cat->first; set; set = set->next) ++cnt;
     mcHead.numSets = cnt;