ext/markdown/autolink.c in github-markdown-0.6.5 vs ext/markdown/autolink.c in github-markdown-0.6.6

@@ -133,20 +133,24 @@
 }
 
 static size_t
 check_domain(uint8_t *data, size_t size, int allow_short)
 {
-	size_t i, np = 0;
+	size_t i, np = 0, uscore1 = 0, uscore2 = 0;
 
-	if (!isalnum(data[0]))
-		return 0;
-
-	for (i = 1; i < size - 1; ++i) {
-		if (data[i] == '.') np++;
+	for (i = 1; i < size - 1; i++) {
+		if (data[i] == '_') uscore2++;
+		else if (data[i] == '.') {
+			uscore1 = uscore2;
+			uscore2 = 0;
+			np++;
+		}
 		else if (!isalnum(data[i]) && data[i] != '-') break;
 	}
 
+	if (uscore1 > 0 || uscore2 > 0) return 0;
+
 	if (allow_short) {
 		/* We don't need a valid domain in the strict sense (with
 		 * least one dot; so just make sure it's composed of valid
 		 * domain characters and return the length of the the valid
 		 * sequence. */
@@ -167,10 +171,10 @@
 	size_t size,
 	unsigned int flags)
 {
 	size_t link_end;
 
-	if (max_rewind > 0 && !ispunct(data[-1]) && !isspace(data[-1]))
+	if (max_rewind > 0 && data[-1] != '(' && data[-1] != '[' && !isspace(data[-1]))
 		return 0;
 
 	if (size < 4 || memcmp(data, "www.", strlen("www.")) != 0)
 		return 0;