Fix: check lttng-modules ABI version for RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS support

[lttng-tools.git] / src / bin / lttng-sessiond / notification-thread-events.c

diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c
index 0fd97e4e2f1e95172f4c4cb2883d2dd627d18b95..793499c4eebb40218ceb1ac651d18b59a520edbe 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread-events.c
+++ b/src/bin/lttng-sessiond/notification-thread-events.c
@@ -97,6 +97,11 @@ struct notification_client {
        struct cds_lfht_node client_socket_ht_node;
        struct {
                struct {
+                       /*
+                        * During the reception of a message, the reception
+                        * buffers' "size" is set to contain the current
+                        * message's complete payload.
+                        */
                        struct lttng_dynamic_buffer buffer;
                        /* Bytes left to receive for the current message. */
                        size_t bytes_to_receive;
@@ -106,12 +111,13 @@ struct notification_client {
                         * Indicates whether or not credentials are expected
                         * from the client.
                         */
-                       bool receive_creds;
+                       bool expect_creds;
                        /*
                         * Indicates whether or not credentials were received
                         * from the client.
                         */
                        bool creds_received;
+                       /* Only used during credentials reception. */
                        lttng_sock_cred creds;
                } inbound;
                struct {
@@ -1153,7 +1159,7 @@ end:
 }
 
 static
-void client_reset_inbound_state(struct notification_client *client)
+int client_reset_inbound_state(struct notification_client *client)
 {
        int ret;
 
@@ -1165,9 +1171,12 @@ void client_reset_inbound_state(struct notification_client *client)
                        sizeof(struct lttng_notification_channel_message);
        client->communication.inbound.msg_type =
                        LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN;
-       client->communication.inbound.receive_creds = false;
        LTTNG_SOCK_SET_UID_CRED(&client->communication.inbound.creds, -1);
        LTTNG_SOCK_SET_GID_CRED(&client->communication.inbound.creds, -1);
+       ret = lttng_dynamic_buffer_set_size(
+                       &client->communication.inbound.buffer,
+                       client->communication.inbound.bytes_to_receive);
+       return ret;
 }
 
 int handle_notification_thread_client_connect(
@@ -1187,7 +1196,13 @@ int handle_notification_thread_client_connect(
        CDS_INIT_LIST_HEAD(&client->condition_list);
        lttng_dynamic_buffer_init(&client->communication.inbound.buffer);
        lttng_dynamic_buffer_init(&client->communication.outbound.buffer);
-       client_reset_inbound_state(client);
+       client->communication.inbound.expect_creds = true;
+       ret = client_reset_inbound_state(client);
+       if (ret) {
+               ERR("[notification-thread] Failed to reset client communication's inbound state");
+               ret = 0;
+               goto error;
+       }
 
        ret = lttcomm_accept_unix_sock(state->notification_channel_socket);
        if (ret < 0) {
@@ -1476,12 +1491,8 @@ int client_dispatch_message(struct notification_client *client,
                client->communication.inbound.bytes_to_receive = msg->size;
                client->communication.inbound.msg_type =
                                (enum lttng_notification_channel_message_type) msg->type;
-               if (client->communication.inbound.msg_type ==
-                               LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE) {
-                       client->communication.inbound.receive_creds = true;
-               }
                ret = lttng_dynamic_buffer_set_size(
-                               &client->communication.inbound.buffer, 0);
+                               &client->communication.inbound.buffer, msg->size);
                if (ret) {
                        goto end;
                }
@@ -1548,7 +1559,11 @@ int client_dispatch_message(struct notification_client *client,
                }
 
                /* Set reception state to receive the next message header. */
-               client_reset_inbound_state(client);
+               ret = client_reset_inbound_state(client);
+               if (ret) {
+                       ERR("[notification-thread] Failed to reset client communication's inbound state");
+                       goto end;
+               }
                client->validated = true;
                break;
        }
@@ -1595,7 +1610,11 @@ int client_dispatch_message(struct notification_client *client,
                }
 
                /* Set reception state to receive the next message header. */
-               client_reset_inbound_state(client);
+               ret = client_reset_inbound_state(client);
+               if (ret) {
+                       ERR("[notification-thread] Failed to reset client communication's inbound state");
+                       goto end;
+               }
                break;
        }
        default:
@@ -1609,7 +1628,7 @@ end:
 int handle_notification_thread_client_in(
                struct notification_thread_state *state, int socket)
 {
-       int ret;
+       int ret = 0;
        struct notification_client *client;
        ssize_t recv_ret;
        size_t offset;
@@ -1621,26 +1640,15 @@ int handle_notification_thread_client_in(
                goto end;
        }
 
-       offset = client->communication.inbound.buffer.size;
-       /*
-        * The buffer's size starts out at the size of the command header.
-        * Once the command is determined, the "bytes_to_receive" are bumped
-        * to fit the remainder of the message being received.
-        */
-       ret = lttng_dynamic_buffer_set_size(
-                       &client->communication.inbound.buffer,
-                       client->communication.inbound.bytes_to_receive + offset);
-       if (ret) {
-               goto end;
-       }
-
-       if (client->communication.inbound.receive_creds) {
+       offset = client->communication.inbound.buffer.size -
+                       client->communication.inbound.bytes_to_receive;
+       if (client->communication.inbound.expect_creds) {
                recv_ret = lttcomm_recv_creds_unix_sock(socket,
                                client->communication.inbound.buffer.data + offset,
                                client->communication.inbound.bytes_to_receive,
                                &client->communication.inbound.creds);
                if (recv_ret > 0) {
-                       client->communication.inbound.receive_creds = false;
+                       client->communication.inbound.expect_creds = false;
                        client->communication.inbound.creds_received = true;
                }
        } else {
@@ -1653,14 +1661,6 @@ int handle_notification_thread_client_in(
        }
 
        client->communication.inbound.bytes_to_receive -= recv_ret;
-       ret = lttng_dynamic_buffer_set_size(
-                       &client->communication.inbound.buffer,
-                       client->communication.inbound.buffer.size -
-                       client->communication.inbound.bytes_to_receive);
-       if (ret) {
-               goto end;
-       }
-
        if (client->communication.inbound.bytes_to_receive == 0) {
                ret = client_dispatch_message(client, state);
                if (ret) {