Check for errors on stratum recv for any recv return value less than 1 and only parse the response if it's positive.

util.c

@@ -1104,17 +1104,19 @@ char *recv_line(struct pool *pool)
 
 			memset(s, 0, RBUFSIZE);
 			n = recv(pool->sock, s, RECVSIZE, 0);
-			if (!n) {
+			if (n < 1) {
+				if (errno != EAGAIN && errno != EWOULDBLOCK) {
+					if (n == 0)
 						ret = RECV_CLOSED;
-				break;
-			}
-			if (n < 0 && errno != EAGAIN && errno != EWOULDBLOCK) {
+					else
 						ret = RECV_RECVFAIL;
 					break;
 				}
+			} else {
 				slen = strlen(s);
 				recalloc_sock(pool, slen);
 				strcat(pool->sockbuf, s);
+			}
 			cgtime(&now);
 		} while (tdiff(&now, &rstart) < 60 && !strstr(pool->sockbuf, "\n"));
 		mutex_unlock(&pool->stratum_lock);