Hi Luiz,
On 14 November 2014 13:44, Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx> wrote:
> Hi Marcin,
>
> On Thu, Nov 13, 2014 at 1:27 PM, Marcin Kraglak
> <marcin.kraglak@xxxxxxxxx> wrote:
>> This is exposed to allow client reading characteristic values
>> with known uuid.
>> ---
>> src/shared/gatt-client.c | 271 +++++++++++++++++++++++++++++++++++++++++++++++
>> src/shared/gatt-client.h | 18 ++++
>> 2 files changed, 289 insertions(+)
>>
>> diff --git a/src/shared/gatt-client.c b/src/shared/gatt-client.c
>> index 30b271e..0493b05 100644
>> --- a/src/shared/gatt-client.c
>> +++ b/src/shared/gatt-client.c
>> @@ -44,6 +44,11 @@
>> #define GATT_SVC_UUID 0x1801
>> #define SVC_CHNGD_UUID 0x2a05
>>
>> +static const uint8_t bt_base_uuid[16] = {
>> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
>> + 0x80, 0x00, 0x00, 0x80, 0x5F, 0x9B, 0x34, 0xFB
>> +};
>> +
>> struct chrc_data {
>> /* The public characteristic entry. */
>> bt_gatt_characteristic_t chrc_external;
>> @@ -122,6 +127,15 @@ struct bt_gatt_client {
>> bool in_svc_chngd;
>> };
>>
>> +static bool is_bluetooth_uuid(const uint8_t uuid[BT_GATT_UUID_SIZE])
>> +{
>> + if (memcmp(uuid, bt_base_uuid, 2) ||
>> + memcmp(&uuid[4], &bt_base_uuid[4], 12))
>> + return false;
>> +
>> + return true;
>> +}
>> +
>
> Is this really different from uuid_cmp? Perhaps you use set uuid16
> properly it should just do the same you are doing above.
Ok, I'll use it.
>
>> struct notify_data {
>> struct bt_gatt_client *client;
>> bool removed;
>> @@ -2001,6 +2015,263 @@ bool bt_gatt_client_read_long_value(struct bt_gatt_client *client,
>> return true;
>> }
>>
>> +struct read_by_uuid_res {
>> + uint16_t handle;
>> + uint8_t length;
>> + uint8_t *data;
>> + struct read_by_uuid_res *next;
>> +};
>> +
>> +bool read_by_uuid_res_get(struct read_by_uuid_res *result, uint16_t *handle,
>> + uint8_t *length, uint8_t **data)
>> +{
>> + if (!result)
>> + return false;
>> +
>> + *length = result->length;
>> + *handle = result->handle;
>> + *data = result->data;
>> +
>> + return true;
>> +}
>> +
>> +struct read_by_uuid_res *read_by_uuid_res_next(struct read_by_uuid_res *result)
>> +{
>> + if (!result)
>> + return NULL;
>> +
>> + return result->next;
>> +}
>> +
>> +struct read_by_uuid_op {
>> + struct bt_gatt_client *client;
>> + bt_gatt_client_read_by_uuid_callback_t callback;
>> + int ref_count;
>> + uint16_t start_handle;
>> + uint16_t end_handle;
>> + uint8_t uuid[BT_GATT_UUID_SIZE];
>> + struct read_by_uuid_res *result_head;
>> + struct read_by_uuid_res *result_tail;
>> + void *user_data;
>> + bt_gatt_client_destroy_func_t destroy;
>> +};
>
> Im not really sure this lists are really helping us, perhaps this is
> the effect of using iterators in the API but that seems to create
> duplicated code.
>
>> +static bool append_read_by_uuid_result(struct read_by_uuid_op *op,
>> + uint16_t handle, uint16_t length,
>> + const uint8_t *data)
>> +{
>> + struct read_by_uuid_res *result;
>> +
>> + result = new0(struct read_by_uuid_res, 1);
>> + if (!result)
>> + return false;
>> +
>> + result->data = malloc(length);
>> + if (!result->data) {
>> + free(result);
>> + return false;
>> + }
>> +
>> + result->handle = handle;
>> + result->length = length;
>> + memcpy(result->data, data, length);
>> +
>> + if (op->result_head) {
>> + op->result_tail->next = result;
>> + op->result_tail = result;
>> + } else {
>> + op->result_head = op->result_tail = result;
>> + }
>> +
>> + return true;
>> +}
>> +
>> +static void destroy_read_by_uuid_result(void *data)
>> +{
>> + struct read_by_uuid_res *result = data;
>> +
>> + free(result->data);
>> + free(result);
>> +}
>> +
>> +static struct read_by_uuid_op *read_by_uuid_op_ref(struct read_by_uuid_op *op)
>> +{
>> + __sync_fetch_and_add(&op->ref_count, 1);
>> +
>> + return op;
>> +}
>> +
>> +static void read_by_uuid_op_unref(void *data)
>> +{
>> + struct read_by_uuid_res *next, *temp;
>> + struct read_by_uuid_op *op = data;
>> +
>> + if (__sync_sub_and_fetch(&op->ref_count, 1))
>> + return;
>> +
>> + if (op->destroy)
>> + op->destroy(op->user_data);
>> +
>> + for (temp = op->result_head; temp; temp = next) {
>> + next = temp->next;
>> + destroy_read_by_uuid_result(temp);
>> + }
>> +
>> + free(op);
>> +}
>> +
>> +static void read_by_uuid_cb(uint8_t opcode, const void *pdu,
>> + uint16_t length, void *user_data)
>> +{
>> + struct read_by_uuid_op *op = user_data;
>> + size_t data_length;
>> + uint8_t att_ecode;
>> + uint16_t offset, last_handle;
>> + const uint8_t *data;
>> + bool success;
>> +
>> + if (opcode == BT_ATT_OP_ERROR_RSP) {
>> + att_ecode = process_error(pdu, length);
>> + if (att_ecode == BT_ATT_ERROR_ATTRIBUTE_NOT_FOUND)
>> + success = true;
>> + else
>> + success = false;
>> +
>> + goto done;
>> + }
>> +
>> + if (opcode != BT_ATT_OP_READ_BY_TYPE_RSP || (!pdu && length)) {
>> + success = false;
>> + att_ecode = 0;
>> + goto done;
>> + }
>> +
>> + data_length = ((const uint8_t *) pdu)[0];
>> + if ((length - 1) % data_length) {
>> + success = false;
>> + att_ecode = 0;
>> + goto done;
>> + }
>> +
>> + for (offset = 1; offset < length; offset += data_length) {
>> + data = pdu + offset;
>> + if (!append_read_by_uuid_result(op, get_le16(data),
>> + data_length - 2, data + 2)) {
>> + success = false;
>> + att_ecode = 0;
>> + goto done;
>> + }
>> + }
>> +
>> + last_handle = get_le16(pdu + length - data_length);
>> + if (last_handle < op->end_handle) {
>> + uint8_t pdu[20];
>> +
>> + put_le16(last_handle + 1, pdu);
>> + put_le16(op->end_handle, pdu + 2);
>> +
>> + if (is_bluetooth_uuid(op->uuid)) {
>> + put_le16((op->uuid[2] << 8) + op->uuid[3], pdu + 4);
>> + /*
>> + * 2 octets - start handle
>> + * 2 octets - end handle
>> + * 2 octets - 16-bit uuid
>> + */
>> + length = 6;
>> + } else {
>> + bswap_128(&op->uuid, pdu + 4);
>> + /*
>> + * 2 octets - start handle
>> + * 2 octets - end handle
>> + * 16 octets - 128-bit uuid
>> + */
>> + length = 20;
>> + }
>> +
>> + if (!bt_att_send(op->client->att, BT_ATT_OP_READ_BY_TYPE_REQ,
>> + pdu, length, read_by_uuid_cb,
>> + read_by_uuid_op_ref(op),
>> + read_by_uuid_op_unref)) {
>> + read_by_uuid_op_unref(op);
>> + success = false;
>> + att_ecode = 0;
>> + goto done;
>> + }
>> +
>> + return;
>> + }
>> +
>> + success = true;
>> + att_ecode = 0;
>> +
>> +done:
>> + if (op->callback)
>> + op->callback(success, att_ecode, op->result_head,
>> + op->user_data);
>> +}
>> +
>> +bool bt_gatt_client_read_by_uuid(struct bt_gatt_client *client,
>> + uint16_t start_handle, uint16_t end_handle,
>> + const uint8_t uuid[BT_GATT_UUID_SIZE],
>> + bt_gatt_client_read_by_uuid_callback_t callback,
>> + void *user_data,
>> + bt_gatt_client_destroy_func_t destroy)
>> +{
>> + struct read_by_uuid_op *op;
>> + uint16_t length;
>> + uint8_t pdu[20];
>> +
>> + if (!client)
>> + return false;
>> +
>> + if (start_handle > end_handle || start_handle == 0x0000)
>> + return false;
>> +
>> + op = new0(struct read_by_uuid_op, 1);
>> + if (!op)
>> + return false;
>> +
>> + op->client = client;
>> + op->start_handle = start_handle;
>> + op->end_handle = end_handle;
>> + op->destroy = destroy;
>> + op->callback = callback;
>> + op->user_data = user_data;
>> + memcpy(&op->uuid, uuid, 16);
>> +
>> + /* Convert to 16-bit if it is Bluetooth UUID */
>> + if (is_bluetooth_uuid(uuid)) {
>> + put_le16((uuid[2] << 8) + uuid[3], pdu + 4);
>> + /*
>> + * 2 octets - start handle
>> + * 2 octets - end handle
>> + * 2 octets - 16-bit uuid
>> + */
>> + length = 6;
>> + } else {
>> + bswap_128(uuid, pdu + 4);
>> + /*
>> + * 2 octets - start handle
>> + * 2 octets - end handle
>> + * 16 octets - 128-bit uuid
>> + */
>> + length = 20;
>> + }
>> +
>> + put_le16(start_handle, pdu);
>> + put_le16(end_handle, pdu + 2);
>> +
>> + if (!bt_att_send(client->att, BT_ATT_OP_READ_BY_TYPE_REQ, pdu,
>> + length, read_by_uuid_cb,
>> + read_by_uuid_op_ref(op),
>> + read_by_uuid_op_unref)) {
>> + free(op);
>> + return false;
>> + }
>> +
>> + return true;
>> +}
>> +
>> bool bt_gatt_client_write_without_response(struct bt_gatt_client *client,
>> uint16_t value_handle,
>> bool signed_write,
>> diff --git a/src/shared/gatt-client.h b/src/shared/gatt-client.h
>> index adccfc5..921ed75 100644
>> --- a/src/shared/gatt-client.h
>> +++ b/src/shared/gatt-client.h
>> @@ -145,6 +145,24 @@ bool bt_gatt_client_read_long_value(struct bt_gatt_client *client,
>> void *user_data,
>> bt_gatt_client_destroy_func_t destroy);
>>
>> +struct read_by_uuid_res;
>> +
>> +struct read_by_uuid_res *read_by_uuid_res_next(struct read_by_uuid_res *result);
>> +bool read_by_uuid_res_get(struct read_by_uuid_res *result, uint16_t *handle,
>> + uint8_t *length, uint8_t **data);
>> +
>> +typedef void (*bt_gatt_client_read_by_uuid_callback_t)(bool success,
>> + uint8_t att_ecode,
>> + struct read_by_uuid_res *result,
>> + void *user_data);
>> +
>> +bool bt_gatt_client_read_by_uuid(struct bt_gatt_client *client,
>> + uint16_t start_handle, uint16_t end_handle,
>> + const uint8_t uuid[BT_GATT_UUID_SIZE],
>> + bt_gatt_client_read_by_uuid_callback_t callback,
>> + void *user_data,
>> + bt_gatt_client_destroy_func_t destroy);
>
> Isn't this essentially duplicating bt_gatt_service_iter_next_by_uuid?
> I mean we should be reading everything already but this doesn't seems
> to using the cache and in case it is just to fulfill a test perhaps it
> is better to do it in gatt-helpers so we keep bt_gatt_client API
> clean.
It is functionality of GATT client described in chapter 4.8.2 "Read
Using Characteristic UUID".
Difference is that client can read attributes by passing UUID, and
results can contain
different valu lengths. And client interprets results instead of gatt-helpers.
I implemented it here because all read/write operations on
characteristics and descriptors
are exposed in bt_gatt_client, and all discovery stuff is implemented
in gatt_helpers. But if
you don't agree I can change it.
>
>> bool bt_gatt_client_write_without_response(struct bt_gatt_client *client,
>> uint16_t value_handle,
>> bool signed_write,
>> --
>> 1.9.3
>>
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>
>
>
> --
> Luiz Augusto von Dentz
BR
Marcin
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