Hi Marcin,
On Fri, Nov 14, 2014 at 3:13 PM, Marcin Kraglak
<marcin.kraglak@xxxxxxxxx> wrote:
> 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.
I see, it does actually end up reading, perhaps it is a good idea to
keep it here then. In the other hand this API seems to be going in the
same direction that gatt-db had with access by handles, perhaps we
should do an API facelift to access by attribute such as we did with
gatt-db, also the iterator could be replaced with queues which I guess
is not that different in the end.
>>
>>> 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
--
Luiz Augusto von Dentz
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