Return-Path: From: Arman Uguray To: linux-bluetooth@vger.kernel.org Cc: Arman Uguray Subject: [PATCH v2 06/11] shared/gatt: Implement "Descriptor Discovery" procedure. Date: Fri, 25 Jul 2014 15:08:38 -0700 Message-Id: <1406326123-10564-7-git-send-email-armansito@chromium.org> In-Reply-To: <1406326123-10564-1-git-send-email-armansito@chromium.org> References: <1406326123-10564-1-git-send-email-armansito@chromium.org> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: This patch implements bt_gatt_discover_descriptors. --- src/shared/gatt-helpers.c | 155 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 153 insertions(+), 2 deletions(-) diff --git a/src/shared/gatt-helpers.c b/src/shared/gatt-helpers.c index 283e6d2..d02b212 100644 --- a/src/shared/gatt-helpers.c +++ b/src/shared/gatt-helpers.c @@ -691,14 +691,165 @@ bool bt_gatt_discover_characteristics(struct bt_att *att, return true; } +struct discover_descs_op { + struct discovery_op data; + uint16_t end; +}; + +static struct discover_descs_op *discover_descs_op_ref( + struct discover_descs_op *op) +{ + __sync_fetch_and_add(&op->data.ref_count, 1); + + return op; +} + +static void discover_descs_op_unref(void *data) +{ + struct discover_descs_op *op = data; + + if (__sync_sub_and_fetch(&op->data.ref_count, 1)) + return; + + if (op->data.destroy) + op->data.destroy(op->data.user_data); + + list_free(&op->data.results, free); + + free(op); +} + +static void discover_descs_cb(uint8_t opcode, const void *pdu, + uint16_t length, void *user_data) +{ + struct discover_descs_op *op = user_data; + bool success; + uint8_t att_ecode = 0; + struct bt_gatt_list *results = NULL; + uint8_t format; + uint16_t last_handle; + size_t data_length; + int i; + + if (opcode == BT_ATT_OP_ERROR_RSP) { + success = false; + att_ecode = process_error(pdu, length); + + if (att_ecode == BT_ATT_ERROR_ATTRIBUTE_NOT_FOUND && + !list_isempty(&op->data.results)) + goto success; + + goto done; + } + + /* The PDU should contain the following data (sans opcode): + * - Format (1 octet) + * - Attr Data List (at least 4 octets): + * -- 2 octets: Attribute handle + * -- 2 or 16 octets: UUID. + */ + if (opcode != BT_ATT_OP_FIND_INFO_RSP || !pdu || length < 5) { + success = false; + goto done; + } + + format = ((uint8_t *) pdu)[0]; + + if (format == 0x01) + data_length = 4; + else if (format == 0x02) + data_length = 18; + else { + success = false; + goto done; + } + + if ((length - 1) % data_length) { + success = false; + goto done; + } + + for (i = 1; i < length; i += data_length) { + struct bt_gatt_descriptor *descr; + + descr = new0(struct bt_gatt_descriptor, 1); + if (!descr) { + success = false; + goto done; + } + + last_handle = get_le16(pdu + i); + descr->handle = last_handle; + convert_uuid_le(pdu + i + 2, data_length - 2, descr->uuid); + + if (!list_add(&op->data.results, descr)) { + success = false; + goto done; + } + } + + if (last_handle != op->end) { + uint8_t pdu[4]; + + put_le16(last_handle + 1, pdu); + put_le16(op->end, pdu + 2); + + if (bt_att_send(op->data.att, BT_ATT_OP_FIND_INFO_REQ, + pdu, sizeof(pdu), + discover_descs_cb, + discover_descs_op_ref(op), + discover_descs_op_unref)) + return; + + discover_descs_op_unref(op); + success = false; + goto done; + } + +success: + results = op->data.results.head; + success = true; + +done: + if (op->data.callback) + op->data.callback(success, att_ecode, results, + op->data.user_data); +} + bool bt_gatt_discover_descriptors(struct bt_att *att, uint16_t start, uint16_t end, bt_gatt_discovery_callback_t callback, void *user_data, bt_gatt_destroy_func_t destroy) { - /* TODO */ - return false; + struct discover_descs_op *op; + uint8_t pdu[4]; + + if (!att) + return false; + + op = new0(struct discover_descs_op, 1); + if (!op) + return false; + + op->data.att = att; + op->data.callback = callback; + op->data.user_data = user_data; + op->data.destroy = destroy; + op->end = end; + + put_le16(start, pdu); + put_le16(end, pdu + 2); + + if (!bt_att_send(att, BT_ATT_OP_FIND_INFO_REQ, pdu, sizeof(pdu), + discover_descs_cb, + discover_descs_op_ref(op), + discover_descs_op_unref)) { + free(op); + return false; + } + + return true; } bool bt_gatt_read_value(struct bt_att *att, uint16_t value_handle, -- 2.0.0.526.g5318336