Diff between c15608a7febfafe36b5a5ecea68746bde878420b and 4ff2a9985ffac9000a7a0ce46aecf4c382421bd9

Changed Files

File Additions Deletions Status
src/shared/gatt-server.c +55 -6 modified

Full Patch

diff --git a/src/shared/gatt-server.c b/src/shared/gatt-server.c
index 4c492d5..4d9d92f 100644
--- a/src/shared/gatt-server.c
+++ b/src/shared/gatt-server.c
@@ -34,33 +34,82 @@
 #define MAX(a, b) ((a) > (b) ? (a) : (b))
 #endif
 
+#ifndef MIN
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
 struct bt_gatt_server {
 	struct gatt_db *db;
 	struct bt_att *att;
 	int ref_count;
 	uint16_t mtu;
 
+	unsigned int mtu_id;
+
 	bt_gatt_server_debug_func_t debug_callback;
 	bt_gatt_server_destroy_func_t debug_destroy;
 	void *debug_data;
 };
 
-static bool gatt_server_register_att_handlers(struct bt_gatt_server *server)
-{
-	/* TODO */
-	return true;
-}
-
 static void bt_gatt_server_free(struct bt_gatt_server *server)
 {
 	if (server->debug_destroy)
 		server->debug_destroy(server->debug_data);
 
+	bt_att_unregister(server->att, server->mtu_id);
 	bt_att_unref(server->att);
 
 	free(server);
 }
 
+static void encode_error_rsp(uint8_t opcode, uint16_t handle, uint8_t ecode,
+								uint8_t pdu[4])
+{
+	pdu[0] = opcode;
+	pdu[3] = ecode;
+	put_le16(handle, pdu + 1);
+}
+
+static void exchange_mtu_cb(uint8_t opcode, const void *pdu,
+					uint16_t length, void *user_data)
+{
+	struct bt_gatt_server *server = user_data;
+	uint16_t client_rx_mtu;
+	uint16_t final_mtu;
+	uint8_t rsp_pdu[4];
+
+	if (length != 2) {
+		encode_error_rsp(opcode, 0, BT_ATT_ERROR_INVALID_PDU, rsp_pdu);
+		bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, rsp_pdu,
+					sizeof(rsp_pdu), NULL, NULL, NULL);
+		return;
+	}
+
+	client_rx_mtu = get_le16(pdu);
+	final_mtu = MAX(MIN(client_rx_mtu, server->mtu), BT_ATT_DEFAULT_LE_MTU);
+
+	/* Respond with the server MTU */
+	put_le16(server->mtu, rsp_pdu);
+	bt_att_send(server->att, BT_ATT_OP_MTU_RSP, rsp_pdu, 2, NULL, NULL,
+									NULL);
+
+	/* Set MTU to be the minimum */
+	server->mtu = final_mtu;
+	bt_att_set_mtu(server->att, final_mtu);
+}
+
+static bool gatt_server_register_att_handlers(struct bt_gatt_server *server)
+{
+	/* EXCHANGE MTU request */
+	server->mtu_id = bt_att_register(server->att, BT_ATT_OP_MTU_REQ,
+								exchange_mtu_cb,
+								server, NULL);
+	if (!server->mtu_id)
+		return false;
+
+	return true;
+}
+
 struct bt_gatt_server *bt_gatt_server_new(struct gatt_db *db,
 					struct bt_att *att, uint16_t mtu)
 {