Try to extract the sessionid associated with mining.notify on 3rd level array and submit it along with the userid to support mining resume, failing gracefully and restarting if the pool rejects it.

util.c

@@ -1424,6 +1424,34 @@ static bool setup_stratum_curl(struct pool *pool)
 	return true;
 }
 
+static char *get_sessionid(json_t *val)
+{
+	char *ret = NULL;
+	json_t *arr_val;
+	int arrsize, i;
+
+	arr_val = json_array_get(val, 0);
+	if (!arr_val || !json_is_array(arr_val))
+		goto out;
+	arrsize = json_array_size(arr_val);
+	for (i = 0; i < arrsize; i++) {
+		json_t *arr = json_array_get(arr_val, i);
+		char *notify;
+
+		if (!arr | !json_is_array(arr))
+			break;
+		notify = __json_array_string(arr, 0);
+		if (!notify)
+			continue;
+		if (!strncasecmp(notify, "mining.notify", 13)) {
+			ret = json_array_string(arr, 1);
+			break;
+		}
+	}
+out:
+	return ret;
+}
+
 bool initiate_stratum(struct pool *pool)
 {
 	char s[RBUFSIZE], *sret = NULL, *nonce1, *sessionid;
@@ -1436,9 +1464,12 @@ bool initiate_stratum(struct pool *pool)
 		goto out;
 
 resend:
-	if (pool->sessionid)
-		sprintf(s, "{\"id\": %d, \"method\": \"mining.subscribe\", \"params\": [\"%s\"]}", swork_id++, pool->sessionid);
-	else
+	if (!recvd) {
+		if (pool->sessionid)
+			sprintf(s, "{\"id\": %d, \"method\": \"mining.subscribe\", \"params\": [\""PACKAGE"/"VERSION"\", \"%s\"]}", swork_id++, pool->sessionid);
+		else
+			sprintf(s, "{\"id\": %d, \"method\": \"mining.subscribe\", \"params\": [\""PACKAGE"/"VERSION"\"]}", swork_id++);
+	} else
 		sprintf(s, "{\"id\": %d, \"method\": \"mining.subscribe\", \"params\": []}", swork_id++);
 
 	if (!__stratum_send(pool, s, strlen(s))) {
@@ -1483,7 +1514,7 @@ resend:
 		goto out;
 	}
 
-	sessionid = json_array_string(json_array_get(res_val, 0), 1);
+	sessionid = get_sessionid(res_val);
 	if (!sessionid)
 		applog(LOG_DEBUG, "Failed to get sessionid in initiate_stratum");
 	nonce1 = json_array_string(res_val, 1);
@@ -1525,7 +1556,7 @@ out:
 			       pool->pool_no, pool->nonce1, pool->n2size);
 		}
 	} else {
-		if (recvd && pool->sessionid) {
+		if (recvd) {
 			/* Reset the sessionid used for stratum resuming in case the pool
 			* does not support it, or does not know how to respond to the
 			* presence of the sessionid parameter. */