pd_server: Check rounds parameter to be a number

1 files changed, 3 insertions, 3 deletions

diff --git a/pd_server.c b/pd_server.c
index 829a6f7..7c5a01f 100644
--- a/pd_server.c
+++ b/pd_server.c
@@ -35,14 +35,14 @@ main(int argc, char *argv[])
 	int port = 8068;
 	int a_payment = 0, b_payment = 0, rounds, i;
 	int optval = 1;
+	char *endptr;
 
-	if (argc < 2) {
+	errno = 0;
+	if (argc < 2 || (rounds = strtol(argv[1], NULL, 10)) <= 0 || errno!=0) {
 		fprintf(stderr, "usage: %s number-of-rounds\n", argv[0]);
 		exit(EXIT_FAILURE);
 	}
 
-	rounds = atoi(argv[1]);
-
 	sock = socket(AF_INET, SOCK_STREAM, 0);
 	if (sock < 0)
 		return EXIT_FAILURE;