diff mbox series

[v2,08/12] shared/gatt-client: Add support for Read Multiple Variable Length

Message ID 20200228234701.14614-9-luiz.dentz@gmail.com
State New
Headers show
Series [v2,01/12] lib: Add definitions for Enhanced Credits Based Mode | expand

Commit Message

Luiz Augusto von Dentz Feb. 28, 2020, 11:46 p.m. UTC 
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

The Read Multiple Variable Length Request is used to request that the
server read two or more values of a set of attributes that have a
variable or unknown value length and return their values in a
Read Multiple Variable Length Response.
---
 src/shared/gatt-client.c | 42 ++++++++++++++++++++++++++++++++++++----
 1 file changed, 38 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/src/shared/gatt-client.c b/src/shared/gatt-client.c
index 2c5fe14dc..5b6723f97 100644
--- a/src/shared/gatt-client.c
+++ b/src/shared/gatt-client.c
@@ -2642,7 +2642,9 @@  static void read_multiple_cb(uint8_t opcode, const void *pdu, uint16_t length,
 	uint8_t att_ecode;
 	bool success;
 
-	if (opcode != BT_ATT_OP_READ_MULT_RSP || (!pdu && length)) {
+	if ((opcode != BT_ATT_OP_READ_MULT_RSP &&
+			opcode != BT_ATT_OP_READ_MULT_VL_RSP) ||
+			(!pdu && length)) {
 		success = false;
 
 		if (opcode == BT_ATT_OP_ERROR_RSP)
@@ -2657,8 +2659,36 @@  static void read_multiple_cb(uint8_t opcode, const void *pdu, uint16_t length,
 		att_ecode = 0;
 	}
 
-	if (op->callback)
+	if (!op->callback)
+		return;
+
+	if (opcode == BT_ATT_OP_READ_MULT_RSP || att_ecode) {
 		op->callback(success, att_ecode, pdu, length, op->user_data);
+		return;
+	}
+
+	if (length < 2) {
+		op->callback(success, att_ecode, pdu, length, op->user_data);
+		return;
+	}
+
+	/* Parse response */
+	while (length >= 2) {
+		uint16_t len;
+
+		len = get_le16(pdu);
+		length -= 2;
+		pdu += 2;
+
+		/* The Length Value Tuple List may be truncated within the
+		 * first two octets of a tuple due to the size limits of the
+		 * current ATT_MTU.
+		 */
+		if (len > length)
+			length = len;
+
+		op->callback(success, att_ecode, pdu, len, op->user_data);
+	}
 }
 
 unsigned int bt_gatt_client_read_multiple(struct bt_gatt_client *client,
@@ -2670,6 +2700,7 @@  unsigned int bt_gatt_client_read_multiple(struct bt_gatt_client *client,
 	uint8_t pdu[num_handles * 2];
 	struct request *req;
 	struct read_op *op;
+	uint8_t opcode;
 	int i;
 
 	if (!client)
@@ -2699,8 +2730,11 @@  unsigned int bt_gatt_client_read_multiple(struct bt_gatt_client *client,
 	for (i = 0; i < num_handles; i++)
 		put_le16(handles[i], pdu + (2 * i));
 
-	req->att_id = bt_att_send(client->att, BT_ATT_OP_READ_MULT_REQ,
-							pdu, sizeof(pdu),
+	opcode = bt_gatt_client_get_features(client) &
+		BT_GATT_CHRC_CLI_FEAT_EATT ? BT_ATT_OP_READ_MULT_VL_REQ :
+		BT_ATT_OP_READ_MULT_REQ;
+
+	req->att_id = bt_att_send(client->att, opcode, pdu, sizeof(pdu),
 							read_multiple_cb, req,
 							request_unref);
 	if (!req->att_id) {