예제 #1
0
파일: jsonrpc.c 프로젝트: rafaelfonte/ovs
char *
jsonrpc_msg_from_json(struct json *json, struct jsonrpc_msg **msgp)
{
    struct json *method = NULL;
    struct jsonrpc_msg *msg = NULL;
    struct shash *object;
    char *error;

    if (json->type != JSON_OBJECT) {
        error = xstrdup("message is not a JSON object");
        goto exit;
    }
    object = json_object(json);

    method = shash_find_and_delete(object, "method");
    if (method && method->type != JSON_STRING) {
        error = xstrdup("method is not a JSON string");
        goto exit;
    }

    msg = xzalloc(sizeof *msg);
    msg->method = method ? xstrdup(method->u.string) : NULL;
    msg->params = null_from_json_null(shash_find_and_delete(object, "params"));
    msg->result = null_from_json_null(shash_find_and_delete(object, "result"));
    msg->error = null_from_json_null(shash_find_and_delete(object, "error"));
    msg->id = null_from_json_null(shash_find_and_delete(object, "id"));
    msg->type = (msg->result ? JSONRPC_REPLY
                 : msg->error ? JSONRPC_ERROR
                 : msg->id ? JSONRPC_REQUEST
                 : JSONRPC_NOTIFY);
    if (!shash_is_empty(object)) {
        error = xasprintf("message has unexpected member \"%s\"",
                          shash_first(object)->name);
        goto exit;
    }
    error = jsonrpc_msg_is_valid(msg);
    if (error) {
        goto exit;
    }

exit:
    json_destroy(method);
    json_destroy(json);
    if (error) {
        jsonrpc_msg_destroy(msg);
        msg = NULL;
    }
    *msgp = msg;
    return error;
}
예제 #2
0
파일: replication.c 프로젝트: exuuwen/study
void
replication_run(void)
{
    if (!session) {
        return;
    }

    jsonrpc_session_run(session);

    for (int i = 0; jsonrpc_session_is_connected(session) && i < 50; i++) {
        struct jsonrpc_msg *msg;
        unsigned int seqno;

        seqno = jsonrpc_session_get_seqno(session);
        if (seqno != session_seqno || state == RPL_S_INIT) {
            session_seqno = seqno;
            request_ids_clear();
            struct jsonrpc_msg *request;
            request = jsonrpc_create_request("list_dbs",
                                             json_array_create_empty(), NULL);
            request_ids_add(request->id, NULL);
            jsonrpc_session_send(session, request);

            replication_dbs_destroy();
            replication_dbs = replication_db_clone(&local_dbs);

            state = RPL_S_DB_REQUESTED;
            VLOG_DBG("Send list_dbs request");
        }

        msg = jsonrpc_session_recv(session);
        if (!msg) {
            continue;
        }

        if (msg->type == JSONRPC_NOTIFY && state != RPL_S_ERR
            && !strcmp(msg->method, "update")) {
            if (msg->params->type == JSON_ARRAY
                && msg->params->u.array.n == 2
                && msg->params->u.array.elems[0]->type == JSON_STRING) {
                char *db_name = msg->params->u.array.elems[0]->u.string;
                struct ovsdb *db = find_db(db_name);
                if (db) {
                    struct ovsdb_error *error;
                    error = process_notification(msg->params->u.array.elems[1],
                                                 db);
                    if (error) {
                        ovsdb_error_assert(error);
                        state = RPL_S_ERR;
                    }
                }
            }
        } else if (msg->type == JSONRPC_REPLY) {
            struct ovsdb *db;
            if (!request_ids_lookup_and_free(msg->id, &db)) {
                VLOG_WARN("received unexpected reply");
                goto next;
            }

            switch (state) {
            case RPL_S_DB_REQUESTED:
                if (msg->result->type != JSON_ARRAY) {
                    struct ovsdb_error *error;
                    error = ovsdb_error("list-dbs failed",
                                        "list_dbs response is not array");
                    ovsdb_error_assert(error);
                    state = RPL_S_ERR;
                } else {
                    size_t i;
                    for (i = 0; i < msg->result->u.array.n; i++) {
                        const struct json *name = msg->result->u.array.elems[i];
                        if (name->type == JSON_STRING) {
                            /* Send one schema request for each remote DB. */
                            const char *db_name = json_string(name);
                            struct ovsdb *db = find_db(db_name);
                            if (db) {
                                struct jsonrpc_msg *request =
                                    jsonrpc_create_request(
                                        "get_schema",
                                        json_array_create_1(
                                            json_string_create(db_name)),
                                        NULL);

                                request_ids_add(request->id, db);
                                jsonrpc_session_send(session, request);
                            }
                        }
                    }
                    VLOG_DBG("Send schema requests");
                    state = RPL_S_SCHEMA_REQUESTED;
                }
                break;

            case RPL_S_SCHEMA_REQUESTED: {
                struct ovsdb_schema *schema;
                struct ovsdb_error *error;

                error = ovsdb_schema_from_json(msg->result, &schema);
                if (error) {
                    ovsdb_error_assert(error);
                    state = RPL_S_ERR;
                }

                if (db != find_db(schema->name)) {
                    /* Unexpected schema. */
                    VLOG_WARN("unexpected schema %s", schema->name);
                    state = RPL_S_ERR;
                } else if (!ovsdb_schema_equal(schema, db->schema)) {
                    /* Schmea version mismatch. */
                    VLOG_INFO("Schema version mismatch, %s not replicated",
                              schema->name);
                    shash_find_and_delete(replication_dbs, schema->name);
                }
                ovsdb_schema_destroy(schema);

                /* After receiving schemas, reset the local databases that
                 * will be monitored and send out monitor requests for them. */
                if (hmap_is_empty(&request_ids)) {
                    struct shash_node *node, *next;

                    SHASH_FOR_EACH_SAFE (node, next, replication_dbs) {
                        db = node->data;
                        struct ovsdb_error *error = reset_database(db);
                        if (error) {
                            const char *db_name = db->schema->name;
                            shash_find_and_delete(replication_dbs, db_name);
                            ovsdb_error_assert(error);
                            VLOG_WARN("Failed to reset database, "
                                      "%s not replicated.", db_name);
                        }
                    }

                    if (shash_is_empty(replication_dbs)) {
                        VLOG_WARN("Nothing to replicate.");
                        state = RPL_S_ERR;
                    } else {
                        SHASH_FOR_EACH (node, replication_dbs) {
                            db = node->data;
                            struct ovsdb *db = node->data;
                            struct jsonrpc_msg *request =
                                create_monitor_request(db);

                            request_ids_add(request->id, db);
                            jsonrpc_session_send(session, request);
                            VLOG_DBG("Send monitor requests");
                            state = RPL_S_MONITOR_REQUESTED;
                        }
                    }
                }
                break;
            }

            case RPL_S_MONITOR_REQUESTED: {
                /* Reply to monitor requests. */
                struct ovsdb_error *error;
                error = process_notification(msg->result, db);
                if (error) {
                    ovsdb_error_assert(error);
                    state = RPL_S_ERR;
                } else {
                    /* Transition to replicating state after receiving
                     * all replies of "monitor" requests. */
                    if (hmap_is_empty(&request_ids)) {
                        VLOG_DBG("Listening to monitor updates");
                        state = RPL_S_REPLICATING;
                    }
                }
                break;
            }

            case RPL_S_ERR:
                /* Ignore all messages */
                break;

            case RPL_S_INIT:
            case RPL_S_REPLICATING:
            default:
                OVS_NOT_REACHED();
            }
        }