Re: bluetoothctl: how to send notification/indcation from peripheral to central

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Yunhan Wang]

Hi Luiz,

Do you have any idea about this issue?

Best wishes
Yunhan

On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
> Hi
>
> Has any one been able to send notification from LE peripheral to LE
> central using bluetoothctl?
>
> Now I am trying to update "Value" with 0x02 for the below
> characteristic with read and indicate flag, i am expecting a
> notification can be sent from peripheral to central automatically. It
> seems there is no such support in bluetoothctl. Then I do simple code
> change on below, and try to update value via "update-chrc 0x02", well,
> the value has been successfully updated, but there is no
> message/notification sent from peripheral to central automatically. I
> have confirmed that chrc read from central is showing updated value,
> 02, correctly. The question is that how can we send characteristic
> notification/indication using bluez dbus API?
>
> btw, I see the video(BlueZ Meets Zephyr made by Luiz)
> https://www.youtube.com/watch?v=SdmZX5q-XDg
> In 30:05, I see Zephyr is sending notification to bluetoothctl
> automatically. How can we just use bluez dbus API to achieve this?
>
> for example,
> In LE peripheral:
> I setup the below characteristic with read and indicate flag
> register-service 00001820-0000-1000-8000-00805f9b34fb
> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb read,indicate
> register-application
> advertise peripheral
>
> In LE central:
> connect 00:AA:01:00:00:23
> select-attribute /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
> notify on
>
> The code change snippet
> --- a/client/gatt.c
> +++ b/client/gatt.c
> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
> +{
> +    struct chrc *chrc = user_data;
> +
> +    g_free(chrc->value);
> +
> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
> +    g_dbus_emit_property_changed(conn, chrc->path,
> "org.bluez.GattCharacteristic1", "Value");
> +
> +}
> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
> *proxy, wordexp_t *w)
>  {
>         struct service *service;
>         struct chrc *chrc;
> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
> GDBusProxy *proxy, wordexp_t *w)
>         print_chrc(chrc, COLORED_NEW);
>
>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
> +
> +    return chrc;
>  }
>
> --- a/client/main.c
> +++ b/client/main.c
> +static void cmd_update_chrc(const char *arg)
> +{
> +    chrc_set_value1(arg, default_chrc, dbus_conn);
> +
> +}
> +
>  static void cmd_unregister_characteristic(const char *arg)
>  {
>         wordexp_t w;
> @@ -2541,6 +2547,9 @@ static const struct {
>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>                                         cmd_register_characteristic,
>                                         "Register application characteristic" },
> +    { "update-chrc", "<value.>",
> +            cmd_update_chrc,
> +            "update chrc value" },
>
> Thanks
> Best wishes
> Yunhan

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Luiz Augusto von Dentz]

Hi Yunhan

On Mon, Aug 7, 2017 at 9:18 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
> Hi Luiz,
>
> Do you have any idea about this issue?
>
> Best wishes
> Yunhan
>
> On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>> Hi
>>
>> Has any one been able to send notification from LE peripheral to LE
>> central using bluetoothctl?
>>
>> Now I am trying to update "Value" with 0x02 for the below
>> characteristic with read and indicate flag, i am expecting a
>> notification can be sent from peripheral to central automatically. It
>>seems there is no such support in bluetoothctl. Then I do simple code
>> change on below, and try to update value via "update-chrc 0x02", well,
>> the value has been successfully updated, but there is no
>> message/notification sent from peripheral to central automatically. I
>> have confirmed that chrc read from central is showing updated value,
>> 02, correctly. The question is that how can we send characteristic
>> notification/indication using bluez dbus API?

That is up for the application when to generate Value changes, we can
introduce a command to just do that, though using bluetoothctl to
generate notification is not very user friendly.

bluetoothd will notice if the application had update its Value, but in
order for this to work you have to generate the PropertiesChanged
signal.

>> btw, I see the video(BlueZ Meets Zephyr made by Luiz)
>> https://www.youtube.com/watch?v=SdmZX5q-XDg
>> In 30:05, I see Zephyr is sending notification to bluetoothctl
>> automatically.How can we just use bluez dbus API to achieve this?

That is using HRS and emulating the heart rate measurements.

>> for example,
>> In LE peripheral:
>> I setup the below characteristic with read and indicate flag
>> register-service 00001820-0000-1000-8000-00805f9b34fb
>> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb read,indicate
>> register-application
>> advertise peripheral
>>
>> In LE central:
>> connect 00:AA:01:00:00:23
>> select-attribute /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
>> notify on
>>
>> The code change snippet
>> --- a/client/gatt.c
>> +++ b/client/gatt.c
>> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
>> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
>> +{
>> +    struct chrc *chrc = user_data;
>> +
>> +    g_free(chrc->value);
>> +
>> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
>> +    g_dbus_emit_property_changed(conn, chrc->path,
>> "org.bluez.GattCharacteristic1", "Value");
>> +
>> +}
>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
>> *proxy, wordexp_t *w)
>>  {
>>        struct service *service;
>>         struct chrc *chrc;
>> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
>> GDBusProxy *proxy, wordexp_t *w)
>>         print_chrc(chrc, COLORED_NEW);
>>
>>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
>> +
>> +    return chrc;
>>  }
>>
>> --- a/client/main.c
>> +++ b/client/main.c
>> +static void cmd_update_chrc(const char *arg)
>> +{
>> +    chrc_set_value1(arg, default_chrc, dbus_conn);

Where does default_chrc comes from? I guess we would need some way to
select the server attributes in order to update them, again this is
not going to be user friendly since you have to send the notification
one by one. Perhaps an easier way to test this is to register standard
attributes like HRS and enable simulation, so it would act exactly
like zephyr or out example-gatt-server.

This could perhaps be done automatically in case a know service is
registered without any attributes, e.g: HRS, then by the time we
register the application bluetoothctl would take care of registering
the standard attributes for the service.

>> +
>> +}
>> +
>> static void cmd_unregister_characteristic(const char *arg)
>>  {
>>         wordexp_t w;
>> @@ -2541,6 +2547,9 @@ static const struct {
>>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>>                                         cmd_register_characteristic,
>>                                         "Register application characteristic" },
>> +    { "update-chrc", "<value.>",
>> +            cmd_update_chrc,
>> +            "update chrc value" },
>>
>> Thanks
>> Best wishes
>> Yunhan
> --
>To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Luiz Augusto von Dentz

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Yunhan Wang]

Hi Luiz

Thanks for your reply. Do you know how to generate PropertiesChanged
signal after updating 'Value' successfully using C , which
API/function should I use/try?

Thanks
Best wishes
Yunhan

On Mon, Aug 7, 2017 at 2:52 AM, Luiz Augusto von Dentz
<luiz.dentz@gmail.com> wrote:
> Hi Yunhan
>
> On Mon, Aug 7, 2017 at 9:18 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>> Hi Luiz,
>>
>> Do you have any idea about this issue?
>>
>> Best wishes
>> Yunhan
>>
>> On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>>> Hi
>>>
>>> Has any one been able to send notification from LE peripheral to LE
>>> central using bluetoothctl?
>>>
>>> Now I am trying to update "Value" with 0x02 for the below
>>> characteristic with read and indicate flag, i am expecting a
>>> notification can be sent from peripheral to central automatically. It
>>>seems there is no such support in bluetoothctl. Then I do simple code
>>> change on below, and try to update value via "update-chrc 0x02", well,
>>> the value has been successfully updated, but there is no
>>> message/notification sent from peripheral to central automatically. I
>>> have confirmed that chrc read from central is showing updated value,
>>> 02, correctly. The question is that how can we send characteristic
>>> notification/indication using bluez dbus API?
>
> That is up for the application when to generate Value changes, we can
> introduce a command to just do that, though using bluetoothctl to
> generate notification is not very user friendly.
>
> bluetoothd will notice if the application had update its Value, but in
> order for this to work you have to generate the PropertiesChanged
> signal.
>
>>> btw, I see the video(BlueZ Meets Zephyr made by Luiz)
>>> https://www.youtube.com/watch?v=SdmZX5q-XDg
>>> In 30:05, I see Zephyr is sending notification to bluetoothctl
>>> automatically.How can we just use bluez dbus API to achieve this?
>
> That is using HRS and emulating the heart rate measurements.
>
>>> for example,
>>> In LE peripheral:
>>> I setup the below characteristic with read and indicate flag
>>> register-service 00001820-0000-1000-8000-00805f9b34fb
>>> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb read,indicate
>>> register-application
>>> advertise peripheral
>>>
>>> In LE central:
>>> connect 00:AA:01:00:00:23
>>> select-attribute /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
>>> notify on
>>>
>>> The code change snippet
>>> --- a/client/gatt.c
>>> +++ b/client/gatt.c
>>> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
>>> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
>>> +{
>>> +    struct chrc *chrc = user_data;
>>> +
>>> +    g_free(chrc->value);
>>> +
>>> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
>>> +    g_dbus_emit_property_changed(conn, chrc->path,
>>> "org.bluez.GattCharacteristic1", "Value");
>>> +
>>> +}
>>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
>>> *proxy, wordexp_t *w)
>>>  {
>>>        struct service *service;
>>>         struct chrc *chrc;
>>> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
>>> GDBusProxy *proxy, wordexp_t *w)
>>>         print_chrc(chrc, COLORED_NEW);
>>>
>>>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
>>> +
>>> +    return chrc;
>>>  }
>>>
>>> --- a/client/main.c
>>> +++ b/client/main.c
>>> +static void cmd_update_chrc(const char *arg)
>>> +{
>>> +    chrc_set_value1(arg, default_chrc, dbus_conn);
>
> Where does default_chrc comes from? I guess we would need some way to
> select the server attributes in order to update them, again this is
> not going to be user friendly since you have to send the notification
> one by one. Perhaps an easier way to test this is to register standard
> attributes like HRS and enable simulation, so it would act exactly
> like zephyr or out example-gatt-server.
>
> This could perhaps be done automatically in case a know service is
> registered without any attributes, e.g: HRS, then by the time we
> register the application bluetoothctl would take care of registering
> the standard attributes for the service.
>
>>> +
>>> +}
>>> +
>>> static void cmd_unregister_characteristic(const char *arg)
>>>  {
>>>         wordexp_t w;
>>> @@ -2541,6 +2547,9 @@ static const struct {
>>>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>>>                                         cmd_register_characteristic,
>>>                                         "Register application characteristic" },
>>> +    { "update-chrc", "<value.>",
>>> +            cmd_update_chrc,
>>> +            "update chrc value" },
>>>
>>> Thanks
>>> Best wishes
>>> Yunhan
>> --
>>To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
>
>
> --
> Luiz Augusto von Dentz

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Luiz Augusto von Dentz]

Hi Yunhan,

On Mon, Aug 7, 2017 at 2:29 PM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
> Hi Luiz
>
> Thanks for your reply. Do you know how to generate PropertiesChanged
> signal after updating 'Value' successfully using C , which
> API/function should I use/try?

It depends on what binding/library are you using, with libdbus:

https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/gdbus/object.c#n1654

Which is the code that called if you do  g_dbus_emit_property_changed.

> Thanks
> Best wishes
> Yunhan
>
> On Mon, Aug 7, 2017 at 2:52 AM, Luiz Augusto von Dentz
> <luiz.dentz@gmail.com> wrote:
>> Hi Yunhan
>>
>> On Mon, Aug 7, 2017 at 9:18 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>>> Hi Luiz,
>>>
>>>Do you have any idea about this issue?
>>>
>>> Best wishes
>>> Yunhan
>>>
>>> On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>>>> Hi
>>>>
>>>> Has any one been able to send notification from LE peripheral to LE
>>>> central using bluetoothctl?
>>>>
>>>> Now I am trying to update "Value" with 0x02 for the below
>>>> characteristic with read and indicate flag, i am expecting a
>>>> notification can be sent from peripheral to central automatically. It
>>>>seems there is no such support in bluetoothctl.Then I do simple code
>>>> change on below, and try to update value via "update-chrc 0x02", well,
>>>> the value has been successfully updated, but there is no
>>>> message/notification sent from peripheral to central automatically. I
>>>> have confirmed that chrc read from central is showing updated value,
>>>> 02, correctly. The question is that how can we send characteristic
>>>> notification/indication using bluez dbus API?
>>
>> That is up for the application when to generate Value changes, we can
>> introduce a command to just do that, though using bluetoothctl to
>> generate notification is not very user friendly.
>>
>> bluetoothd will notice if the application had update its Value, but in
>> order for this to work you have to generate the PropertiesChanged
>> signal.
>>
>>>> btw, I see the video(BlueZ Meets Zephyr made by Luiz)
>>>> https://www.youtube.com/watch?v=SdmZX5q-XDg
>>>> In 30:05,I see Zephyr is sending notification to bluetoothctl
>>>> automatically.How can we just use bluez dbus API to achieve this?
>>
>> That is using HRS and emulating the heart rate measurements.
>>
>>>> for example,
>>>> In LE peripheral:
>>>>I setup the below characteristic with read and indicate flag
>>>> register-service 00001820-0000-1000-8000-00805f9b34fb
>>>> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb read,indicate
>>>> register-application
>>>> advertise peripheral
>>>>
>>>> In LE central:
>>>> connect 00:AA:01:00:00:23
>>>> select-attribute /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
>>>> notify on
>>>>
>>>> The code change snippet
>>>> --- a/client/gatt.c
>>>> +++ b/client/gatt.c
>>>>-void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
>>>> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
>>>> +{
>>>> +    struct chrc *chrc = user_data;
>>>> +
>>>> +    g_free(chrc->value);
>>>> +
>>>> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
>>>> +    g_dbus_emit_property_changed(conn, chrc->path,
>>>> "org.bluez.GattCharacteristic1", "Value");
>>>> +
>>>> +}
>>>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
>>>> *proxy, wordexp_t *w)
>>>>  {
>>>>        struct service *service;
>>>>         struct chrc *chrc;
>>>> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
>>>> GDBusProxy *proxy, wordexp_t *w)
>>>>         print_chrc(chrc, COLORED_NEW);
>>>>
>>>>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
>>>> +
>>>> +    return chrc;
>>>>  }
>>>>
>>>> --- a/client/main.c
>>>> +++ b/client/main.c
>>>>+static void cmd_update_chrc(const char *arg)
>>>> +{
>>>> +    chrc_set_value1(arg, default_chrc, dbus_conn);
>>
>> Where does default_chrc comes from? I guess we would need some way to
>> select the server attributes in order to update them, again this is
>> not going to be user friendly since you have to send the notification
>> one by one. Perhaps an easier way to test this is to register standard
>>attributes like HRS and enable simulation, so it would act exactly
>> like zephyr or out example-gatt-server.
>>
>> This could perhaps be done automatically in case a know service is
>> registered without any attributes, e.g: HRS, then by the time we
>> register the application bluetoothctl would take care of registering
>> the standard attributes for the service.
>>
>>>> +
>>>> +}
>>>> +
>>>> static void cmd_unregister_characteristic(const char *arg)
>>>>  {
>>>>         wordexp_t w;
>>>> @@ -2541,6 +2547,9 @@ static const struct {
>>>>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>>>>                                         cmd_register_characteristic,
>>>>                                         "Register application characteristic" },
>>>> +    { "update-chrc", "<value.>",
>>>> +            cmd_update_chrc,
>>>> +            "update chrc value" },
>>>>
>>>> Thanks
>>>> Best wishes
>>>> Yunhan
>>> --
>>>To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
>>>the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
>>
>>
>> --
>>Luiz Augusto of Dentz Luiz Augusto of Dentz



-

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Yunhan Wang]

Hi, Luiz

Please see the below comment reply.

Thank you
Best wishes
Yunhan
On Mon, Aug 7, 2017 at 11:49 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>
> Hi, Luiz
>
> This is complete diff I am currently playing.
>
> diff --git a/client/gatt.c b/client/gatt.c
> index bd6e6b0af..548c798a2 100644
> --- a/client/gatt.c
> +++ b/client/gatt.c
> @@ -1449,16 +1449,27 @@ static uint8_t *str2bytearray(char *arg, int *val_len)
>         return g_memdup(value, i);
>  }
>
> -static void chrc_set_value(const char *input, void *user_data)
> +void chrc_set_value(const char *input, void *user_data)
>  {
>         struct chrc *chrc = user_data;
>
>         g_free(chrc->value);
>
>         chrc->value = str2bytearray((char *) input, &chrc->value_len);
> +
>  }
>
> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
> +{
> +    struct chrc *chrc = user_data;
> +
> +    g_free(chrc->value);
> +
> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
> +    g_dbus_emit_property_changed(conn, chrc->path, "org.bluez.GattCharacteristic1", "Value");
> +
> +}

@Luiz, here i am using g_dbus_emit_property_changed, which should
further call process_properties_from_interface, but I cannot see the
value change has been sent from peripheral to central automatically,
anything I am missing?

>
> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
>  {
>         struct service *service;
>         struct chrc *chrc;
> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
>         print_chrc(chrc, COLORED_NEW);
>
>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
> +
> +    return chrc;
>  }
>
>  static struct chrc *chrc_find(const char *pattern)
> diff --git a/client/gatt.h b/client/gatt.h
> index 9bab42902..bddba40e4 100644
> --- a/client/gatt.h
> +++ b/client/gatt.h
> @@ -55,10 +55,11 @@ void gatt_register_service(DBusConnection *conn, GDBusProxy *proxy,
>  void gatt_unregister_service(DBusConnection *conn, GDBusProxy *proxy,
>                                                                 wordexp_t *w);
>
> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w);
> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w);
>  void gatt_unregister_chrc(DBusConnection *conn, GDBusProxy *proxy,
>                                                                 wordexp_t *w);
>
>  void gatt_register_desc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w);
>  void gatt_unregister_desc(DBusConnection *conn, GDBusProxy *proxy,
>                                                                 wordexp_t *w);
> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn);
> \ No newline at end of file
> diff --git a/client/main.c b/client/main.c
> index 40075f27e..6c5ae231d 100644
> --- a/client/main.c
> +++ b/client/main.c
> @@ -78,7 +78,7 @@ static GList *ctrl_list;
>  static GList *ad_manager_list;
>  static guint input = 0;
>  static char * adapter_address;
> -
> +struct chrc * default_chrc;
>  static const char * const agent_arguments[] = {
>         "on",
>         "off",
> @@ -2147,12 +2147,18 @@ static void cmd_register_characteristic(const char *arg)
>                 goto done;
>         }
>
> -       gatt_register_chrc(dbus_conn, default_ctrl->proxy, &w);
> +    default_chrc = gatt_register_chrc(dbus_conn, default_ctrl->proxy, &w);
>
>  done:
>         wordfree(&w);
>  }

@Luiz, here I am testing only one characteristic, and  storing the
default chrc in global variable.

>
>
> +static void cmd_update_chrc(const char *arg)
> +{
> +    chrc_set_value1(arg, default_chrc, dbus_conn);
> +
> +}
> +
>  static void cmd_unregister_characteristic(const char *arg)
>  {
>         wordexp_t w;
> @@ -2541,6 +2547,9 @@ static const struct {
>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>                                         cmd_register_characteristic,
>                                         "Register application characteristic" },
> +    { "update-chrc", "<value>",
> +            cmd_update_chrc,
> +            "update chrc value" },
>         { "unregister-characteristic", "<UUID/object>",
>                                 cmd_unregister_characteristic,
>                                 "Unregister application characteristic" },
>
>
> On Mon, Aug 7, 2017 at 6:15 AM, Luiz Augusto von Dentz <luiz.dentz@gmail.com> wrote:
>>
>> Hi Yunhan,
>>
>> On Mon, Aug 7, 2017 at 2:29 PM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>> > Hi Luiz
>> >
>> > Thanks for your reply. Do you know how to generate PropertiesChanged
>> > signal after updating 'Value' successfully using C , which
>> > API/function should I use/try?
>>
>> It depends on what binding/library are you using, with libdbus:
>>
>> https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/gdbus/object.c#n1654
>>
>> Which is the code that called if you do  g_dbus_emit_property_changed.
>>
>> > Thanks
>> > Best wishes
>> > Yunhan
>> >
>> > On Mon, Aug 7, 2017 at 2:52 AM, Luiz Augusto von Dentz
>> > <luiz.dentz@gmail.com> wrote:
>> >> Hi Yunhan
>> >>
>> >> On Mon, Aug 7, 2017 at 9:18 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>> >>> Hi Luiz,
>> >>>
>> >>>Do you have any idea about this issue?
>> >>>
>> >>> Best wishes
>> >>> Yunhan
>> >>>
>> >>> On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>> >>>> Hi
>> >>>>
>> >>>> Has any one been able to send notification from LE peripheral to LE
>> >>>> central using bluetoothctl?
>> >>>>
>> >>>> Now I am trying to update "Value" with 0x02 for the below
>> >>>> characteristic with read and indicate flag, i am expecting a
>> >>>> notification can be sent from peripheral to central automatically. It
>> >>>>seems there is no such support in bluetoothctl.Then I do simple code
>> >>>> change on below, and try to update value via "update-chrc 0x02", well,
>> >>>> the value has been successfully updated, but there is no
>> >>>> message/notification sent from peripheral to central automatically. I
>> >>>> have confirmed that chrc read from central is showing updated value,
>> >>>> 02, correctly. The question is that how can we send characteristic
>> >>>> notification/indication using bluez dbus API?
>> >>
>> >> That is up for the application when to generate Value changes, we can
>> >> introduce a command to just do that, though using bluetoothctl to
>> >> generate notification is not very user friendly.
>> >>
>> >> bluetoothd will notice if the application had update its Value, but in
>> >> order for this to work you have to generate the PropertiesChanged
>> >> signal.
>> >>
>> >>>> btw, I see the video(BlueZ Meets Zephyr made by Luiz)
>> >>>> https://www.youtube.com/watch?v=SdmZX5q-XDg
>> >>>> In 30:05,I see Zephyr is sending notification to bluetoothctl
>> >>>> automatically.How can we just use bluez dbus API to achieve this?
>> >>
>> >> That is using HRS and emulating the heart rate measurements.
>> >>
>> >>>> for example,
>> >>>> In LE peripheral:
>> >>>>I setup the below characteristic with read and indicate flag
>> >>>> register-service 00001820-0000-1000-8000-00805f9b34fb
>> >>>> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb read,indicate
>> >>>> register-application
>> >>>> advertise peripheral
>> >>>>
>> >>>> In LE central:
>> >>>> connect 00:AA:01:00:00:23
>> >>>> select-attribute /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
>> >>>> notify on
>> >>>>
>> >>>> The code change snippet
>> >>>> --- a/client/gatt.c
>> >>>> +++ b/client/gatt.c
>> >>>>-void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
>> >>>> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
>> >>>> +{
>> >>>> +    struct chrc *chrc = user_data;
>> >>>> +
>> >>>> +    g_free(chrc->value);
>> >>>> +
>> >>>> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
>> >>>> +    g_dbus_emit_property_changed(conn, chrc->path,
>> >>>> "org.bluez.GattCharacteristic1", "Value");
>> >>>> +
>> >>>> +}
>> >>>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
>> >>>> *proxy, wordexp_t *w)
>> >>>>  {
>> >>>>        struct service *service;
>> >>>>         struct chrc *chrc;
>> >>>> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
>> >>>> GDBusProxy *proxy, wordexp_t *w)
>> >>>>         print_chrc(chrc, COLORED_NEW);
>> >>>>
>> >>>>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
>> >>>> +
>> >>>> +    return chrc;
>> >>>>  }
>> >>>>
>> >>>> --- a/client/main.c
>> >>>> +++ b/client/main.c
>> >>>>+static void cmd_update_chrc(const char *arg)
>> >>>> +{
>> >>>> +    chrc_set_value1(arg, default_chrc, dbus_conn);
>> >>
>> >> Where does default_chrc comes from? I guess we would need some way to
>> >> select the server attributes in order to update them, again this is
>> >> not going to be user friendly since you have to send the notification
>> >> one by one. Perhaps an easier way to test this is to register standard
>> >>attributes like HRS and enable simulation, so it would act exactly
>> >> like zephyr or out example-gatt-server.
>> >>
>> >> This could perhaps be done automatically in case a know service is
>> >> registered without any attributes, e.g: HRS, then by the time we
>> >> register the application bluetoothctl would take care of registering
>> >> the standard attributes for the service.
>> >>
>> >>>> +
>> >>>> +}
>> >>>> +
>> >>>> static void cmd_unregister_characteristic(const char *arg)
>> >>>>  {
>> >>>>         wordexp_t w;
>> >>>> @@ -2541,6 +2547,9 @@ static const struct {
>> >>>>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>> >>>>                                         cmd_register_characteristic,
>> >>>>                                         "Register application characteristic" },
>> >>>> +    { "update-chrc", "<value.>",
>> >>>> +            cmd_update_chrc,
>> >>>> +            "update chrc value" },
>> >>>>
>> >>>> Thanks
>> >>>> Best wishes
>> >>>> Yunhan
>> >>> --
>> >>>To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
>> >>>the body of a message to majordomo@vger.kernel.org
>> >>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> >>
>> >>
>> >>
>> >> --
>> >>Luiz Augusto of Dentz Luiz Augusto of Dentz
>>
>>
>>
>> -
>
>

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Yunhan Wang]

Hi, Luiz
May i have another question about this g_dbus_emit_property_changed .

Please see the below inline comments.

Thanks
Best wishes
Yunhan

On Mon, Aug 7, 2017 at 11:49 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
> Hi, Luiz
>
> This is complete diff I am currently playing.
>
> diff --git a/client/gatt.c b/client/gatt.c
> index bd6e6b0af..548c798a2 100644
> --- a/client/gatt.c
> +++ b/client/gatt.c
> @@ -1449,16 +1449,27 @@ static uint8_t *str2bytearray(char *arg, int
> *val_len)
>         return g_memdup(value, i);
>  }
>
> -static void chrc_set_value(const char *input, void *user_data)
> +void chrc_set_value(const char *input, void *user_data)
>  {
>         struct chrc *chrc = user_data;
>
>         g_free(chrc->value);
>
>         chrc->value = str2bytearray((char *) input, &chrc->value_len);
> +
>  }
>
> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t
> *w)
> +void chrc_set_value1(const char *input, void *user_data, DBusConnection
> *conn)
> +{
> +    struct chrc *chrc = user_data;
> +
> +    g_free(chrc->value);
> +
> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
> +    g_dbus_emit_property_changed(conn, chrc->path,
> "org.bluez.GattCharacteristic1", "Value");
> +
For g_dbus_emit_property_changed, it can emit property change signal
to dbus, and then bluetoothd take care of message delivery, but it
seems there is no callback to confirm if this indication is sent. In
contrast, bt_gatt_server_send_indication has the ability to add conf
callback function. Do you know if we can add a callback to monitor
whether property_change's signal is processed, especially for
characteristics under DbusConnection.

> +}
> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy,
> wordexp_t *w)
>  {
>         struct service *service;
>         struct chrc *chrc;
> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
> GDBusProxy *proxy, wordexp_t *w)
>         print_chrc(chrc, COLORED_NEW);
>
>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
> +
> +    return chrc;
>  }
>
>  static struct chrc *chrc_find(const char *pattern)
> diff --git a/client/gatt.h b/client/gatt.h
> index 9bab42902..bddba40e4 100644
> --- a/client/gatt.h
> +++ b/client/gatt.h
> @@ -55,10 +55,11 @@ void gatt_register_service(DBusConnection *conn,
> GDBusProxy *proxy,
>  void gatt_unregister_service(DBusConnection *conn, GDBusProxy *proxy,
>                                                                 wordexp_t
> *w);
>
> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t
> *w);
> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy,
> wordexp_t *w);
>  void gatt_unregister_chrc(DBusConnection *conn, GDBusProxy *proxy,
>                                                                 wordexp_t
> *w);
>
>  void gatt_register_desc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t
> *w);
>  void gatt_unregister_desc(DBusConnection *conn, GDBusProxy *proxy,
>                                                                 wordexp_t
> *w);
> +void chrc_set_value1(const char *input, void *user_data, DBusConnection
> *conn);
> \ No newline at end of file
> diff --git a/client/main.c b/client/main.c
> index 40075f27e..6c5ae231d 100644
> --- a/client/main.c
> +++ b/client/main.c
> @@ -78,7 +78,7 @@ static GList *ctrl_list;
>  static GList *ad_manager_list;
>  static guint input = 0;
>  static char * adapter_address;
> -
> +struct chrc * default_chrc;
>  static const char * const agent_arguments[] = {
>         "on",
>         "off",
> @@ -2147,12 +2147,18 @@ static void cmd_register_characteristic(const char
> *arg)
>                 goto done;
>         }
>
> -       gatt_register_chrc(dbus_conn, default_ctrl->proxy, &w);
> +    default_chrc = gatt_register_chrc(dbus_conn, default_ctrl->proxy, &w);
>
>  done:
>         wordfree(&w);
>  }
>
> +static void cmd_update_chrc(const char *arg)
> +{
> +    chrc_set_value1(arg, default_chrc, dbus_conn);
> +
> +}
> +
>  static void cmd_unregister_characteristic(const char *arg)
>  {
>         wordexp_t w;
> @@ -2541,6 +2547,9 @@ static const struct {
>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>                                         cmd_register_characteristic,
>                                         "Register application
> characteristic" },
> +    { "update-chrc", "<value>",
> +            cmd_update_chrc,
> +            "update chrc value" },
>         { "unregister-characteristic", "<UUID/object>",
>                                 cmd_unregister_characteristic,
>                                 "Unregister application characteristic" },
>
>
> On Mon, Aug 7, 2017 at 6:15 AM, Luiz Augusto von Dentz
> <luiz.dentz@gmail.com> wrote:
>>
>> Hi Yunhan,
>>
>> On Mon, Aug 7, 2017 at 2:29 PM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>> > Hi Luiz
>> >
>> > Thanks for your reply. Do you know how to generate PropertiesChanged
>> > signal after updating 'Value' successfully using C , which
>> > API/function should I use/try?
>>
>> It depends on what binding/library are you using, with libdbus:
>>
>>
>> https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/gdbus/object.c#n1654
>>
>> Which is the code that called if you do  g_dbus_emit_property_changed.
>>
>> > Thanks
>> > Best wishes
>> > Yunhan
>> >
>> > On Mon, Aug 7, 2017 at 2:52 AM, Luiz Augusto von Dentz
>> > <luiz.dentz@gmail.com> wrote:
>> >> Hi Yunhan
>> >>
>> >> On Mon, Aug 7, 2017 at 9:18 AM, Yunhan Wang <yunhanw@nestlabs.com>
>> >> wrote:
>> >>> Hi Luiz,
>> >>>
>> >>>Do you have any idea about this issue?
>> >>>
>> >>> Best wishes
>> >>> Yunhan
>> >>>
>> >>> On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com>
>> >>> wrote:
>> >>>> Hi
>> >>>>
>> >>>> Has any one been able to send notification from LE peripheral to LE
>> >>>> central using bluetoothctl?
>> >>>>
>> >>>> Now I am trying to update "Value" with 0x02 for the below
>> >>>> characteristic with read and indicate flag, i am expecting a
>> >>>> notification can be sent from peripheral to central automatically. It
>> >>>>seems there is no such support in bluetoothctl.Then I do simple code
>> >>>> change on below, and try to update value via "update-chrc 0x02",
>> >>>> well,
>> >>>> the value has been successfully updated, but there is no
>> >>>> message/notification sent from peripheral to central automatically. I
>> >>>> have confirmed that chrc read from central is showing updated value,
>> >>>> 02, correctly. The question is that how can we send characteristic
>> >>>> notification/indication using bluez dbus API?
>> >>
>> >> That is up for the application when to generate Value changes, we can
>> >> introduce a command to just do that, though using bluetoothctl to
>> >> generate notification is not very user friendly.
>> >>
>> >> bluetoothd will notice if the application had update its Value, but in
>> >> order for this to work you have to generate the PropertiesChanged
>> >> signal.
>> >>
>> >>>> btw, I see the video(BlueZ Meets Zephyr made by Luiz)
>> >>>> https://www.youtube.com/watch?v=SdmZX5q-XDg
>> >>>> In 30:05,I see Zephyr is sending notification to bluetoothctl
>> >>>> automatically.How can we just use bluez dbus API to achieve this?
>> >>
>> >> That is using HRS and emulating the heart rate measurements.
>> >>
>> >>>> for example,
>> >>>> In LE peripheral:
>> >>>>I setup the below characteristic with read and indicate flag
>> >>>> register-service 00001820-0000-1000-8000-00805f9b34fb
>> >>>> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb
>> >>>> read,indicate
>> >>>> register-application
>> >>>> advertise peripheral
>> >>>>
>> >>>> In LE central:
>> >>>> connect 00:AA:01:00:00:23
>> >>>> select-attribute
>> >>>> /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
>> >>>> notify on
>> >>>>
>> >>>> The code change snippet
>> >>>> --- a/client/gatt.c
>> >>>> +++ b/client/gatt.c
>> >>>>-void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy,
>> >>>> wordexp_t *w)
>> >>>> +void chrc_set_value1(const char *input, void *user_data,
>> >>>> DBusConnection *conn)
>> >>>> +{
>> >>>> +    struct chrc *chrc = user_data;
>> >>>> +
>> >>>> +    g_free(chrc->value);
>> >>>> +
>> >>>> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
>> >>>> +    g_dbus_emit_property_changed(conn, chrc->path,
>> >>>> "org.bluez.GattCharacteristic1", "Value");
>> >>>> +
>> >>>> +}
>> >>>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
>> >>>> *proxy, wordexp_t *w)
>> >>>>  {
>> >>>>        struct service *service;
>> >>>>         struct chrc *chrc;
>> >>>> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
>> >>>> GDBusProxy *proxy, wordexp_t *w)
>> >>>>         print_chrc(chrc, COLORED_NEW);
>> >>>>
>> >>>>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value,
>> >>>> chrc);
>> >>>> +
>> >>>> +    return chrc;
>> >>>>  }
>> >>>>
>> >>>> --- a/client/main.c
>> >>>> +++ b/client/main.c
>> >>>>+static void cmd_update_chrc(const char *arg)
>> >>>> +{
>> >>>> +    chrc_set_value1(arg, default_chrc, dbus_conn);
>> >>
>> >> Where does default_chrc comes from? I guess we would need some way to
>> >> select the server attributes in order to update them, again this is
>> >> not going to be user friendly since you have to send the notification
>> >> one by one. Perhaps an easier way to test this is to register standard
>> >>attributes like HRS and enable simulation, so it would act exactly
>> >> like zephyr or out example-gatt-server.
>> >>
>> >> This could perhaps be done automatically in case a know service is
>> >> registered without any attributes, e.g: HRS, then by the time we
>> >> register the application bluetoothctl would take care of registering
>> >> the standard attributes for the service.
>> >>
>> >>>> +
>> >>>> +}
>> >>>> +
>> >>>> static void cmd_unregister_characteristic(const char *arg)
>> >>>>  {
>> >>>>         wordexp_t w;
>> >>>> @@ -2541,6 +2547,9 @@ static const struct {
>> >>>>         { "register-characteristic", "<UUID>
>> >>>> <Flags=read,write,notify...>",
>> >>>>                                         cmd_register_characteristic,
>> >>>>                                         "Register application
>> >>>> characteristic" },
>> >>>> +    { "update-chrc", "<value.>",
>> >>>> +            cmd_update_chrc,
>> >>>> +            "update chrc value" },
>> >>>>
>> >>>> Thanks
>> >>>> Best wishes
>> >>>> Yunhan
>> >>> --
>> >>>To unsubscribe from this list: send the line "unsubscribe
>> >>> linux-bluetooth" in
>> >>>the body of a message to majordomo@vger.kernel.org
>> >>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> >>
>> >>
>> >>
>> >> --
>> >>Luiz Augusto of Dentz Luiz Augusto of Dentz
>>
>>
>>
>> -
>
>

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Luiz Augusto von Dentz]

Hi Yunhan,

On Tue, Aug 8, 2017 at 11:40 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
> Hi, Luiz
> May i have another question about this g_dbus_emit_property_changed .
>
> Please see the below inline comments.

We only use inline comments in the list.

> Thanks
> Best wishes
> Yunhan
>
> On Mon, Aug 7, 2017 at 11:49 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>> Hi, Luiz
>>
>> This is complete diff I am currently playing.
>>
>> diff --git a/client/gatt.c b/client/gatt.c
>> index bd6e6b0af..548c798a2 100644
>> --- a/client/gatt.c
>> +++ b/client/gatt.c
>> @@ -1449,16 +1449,27 @@ static uint8_t *str2bytearray(char *arg, int
>> *val_len)
>>         return g_memdup(value, i);
>>  }
>>
>> -static void chrc_set_value(const char *input, void *user_data)
>> +void chrc_set_value(const char *input, void *user_data)
>>  {
>>         struct chrc *chrc = user_data;
>>
>>         g_free(chrc->value);
>>
>>         chrc->value = str2bytearray((char *) input, &chrc->value_len);
>> +
>>  }
>>
>> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t
>> *w)
>> +void chrc_set_value1(const char *input,void *user_data, DBusConnection
>> *conn)
>> +{
>> +    struct chrc *chrc = user_data;
>> +
>> +    g_free(chrc->value);
>> +
>> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
>> +    g_dbus_emit_property_changed(conn, chrc->path,
>> "org.bluez.GattCharacteristic1", "Value");
>> +
> For g_dbus_emit_property_changed, it can emit property change signal
> to dbus, and then bluetoothd take care of message delivery, but it
> seems there is no callback to confirm if this indication is sent. In
> contrast,bt_gatt_server_send_indication has the ability to add conf
> callback function. Do you know if we can add a callback to monitor
> whether property_change's signal is processed, especially for
> characteristics under DbusConnection.

D-Bus signals don't have a reply, so we can't really return a
confirmation. iirc we do queue up in case of indications so they are
not sent until confirmations are received, if that is not enough then
we need to think in another way to deliver confirmations.

>> +}
>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy,
>> wordexp_t *w)
>>  {
>>         struct service *service;
>>         struct chrc *chrc;
>> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
>> GDBusProxy *proxy, wordexp_t *w)
>>         print_chrc(chrc, COLORED_NEW);
>>
>>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
>> +
>> +    return chrc;
>>  }
>>
>>  static struct chrc *chrc_find(const char *pattern)
>> diff --git a/client/gatt.h b/client/gatt.h
>> index 9bab42902..bddba40e4 100644
>> --- a/client/gatt.h
>> +++ b/client/gatt.h
>> @@ -55,10 +55,11 @@ void gatt_register_service(DBusConnection *conn,
>> GDBusProxy *proxy,
>>  void gatt_unregister_service(DBusConnection *conn, GDBusProxy *proxy,
>>                                                                 wordexp_t
>> *w);
>>
>> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy,wordexp_t
>> *w);
>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy,
>> wordexp_t *w);
>>  void gatt_unregister_chrc(DBusConnection *conn, GDBusProxy *proxy,
>>                                                                 wordexp_t
>> *w);
>>
>>  void gatt_register_desc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t
>> *w);
>>  void gatt_unregister_desc(DBusConnection *conn, GDBusProxy *proxy,
>>                                                                 wordexp_t
>> *w);
>> +void chrc_set_value1(const char *input, void *user_data, DBusConnection
>> *conn);
>> \ No newline at end of file
>> diff --git a/client/main.c b/client/main.c
>> index 40075f27e..6c5ae231d 100644
>> --- a/client/main.c
>> +++ b/client/main.c
>> @@ -78,7 +78,7 @@ static GList *ctrl_list;
>>  static GList *ad_manager_list;
>>  static guint input = 0;
>>  static char * adapter_address;
>> -
>> +struct chrc * default_chrc;
>>  static const char * const agent_arguments[] = {
>>         "on",
>>         "off",
>> @@ -2147,12 +2147,18 @@ static void cmd_register_characteristic(const char
>> *arg)
>>                 goto done;
>>         }
>>
>> -       gatt_register_chrc(dbus_conn, default_ctrl->proxy, &w);
>> +    default_chrc = gatt_register_chrc(dbus_conn, default_ctrl->proxy, &w);
>>
>>  done:
>>         wordfree(&w);
>>  }
>>
>> +static void cmd_update_chrc(const char *arg)
>> +{
>> +    chrc_set_value1(arg, default_chrc, dbus_conn);
>> +
>> +}
>> +
>>  static void cmd_unregister_characteristic(const char *arg)
>>  {
>>         wordexp_t w;
>> @@ -2541,6 +2547,9 @@ static const struct {
>>        { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>>                                         cmd_register_characteristic,
>>                                         "Register application
>> characteristic" },
>> +    { "update-chrc", "<value>",
>> +            cmd_update_chrc,
>> +            "update chrc value" },
>>         { "unregister-characteristic", "<UUID/object>",
>>                                 cmd_unregister_characteristic,
>>                                 "Unregister application characteristic" },
>>
>>
>> On Mon, Aug 7, 2017 at 6:15 AM, Luiz Augusto von Dentz
>> <luiz.dentz@gmail.com> wrote:
>>>
>>> Hi Yunhan,
>>>
>>> On Mon, Aug 7, 2017 at 2:29 PM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
>>> > Hi Luiz
>>> >
>>> > Thanks for your reply. Do you know how to generate PropertiesChanged
>>> > signal after updating 'Value' successfully using C , which
>>> > API/function should I use/try?
>>>
>>> It depends on what binding/library are you using, with libdbus:
>>>
>>>
>>> https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/gdbus/object.c#n1654
>>>
>>> Which is the code that called if you do  g_dbus_emit_property_changed.
>>>
>>> > Thanks
>>> > Best wishes
>>> > Yunhan
>>> >
>>> > On Mon, Aug 7, 2017 at 2:52 AM, Luiz Augusto von Dentz
>>> > <luiz.dentz@gmail.com> wrote:
>>> >> Hi Yunhan
>>> >>
>>> >> On Mon, Aug 7, 2017 at 9:18 AM, Yunhan Wang <yunhanw@nestlabs.com>
>>> >> wrote:
>>> >>> Hi Luiz,
>>> >>>
>>> >>>Do you have any idea about this issue?
>>> >>>
>>> >>> Best wishes
>>> >>> Yunhan
>>> >>>
>>> >>> On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com>
>>> >>> wrote:
>>> >>>> Hi
>>> >>>>
>>> >>>> Has any one been able to send notification from LE peripheral to LE
>>> >>>> central using bluetoothctl?
>>> >>>>
>>> >>>> Now I am trying to update "Value" with 0x02 for the below
>>> >>>>characteristic with read and indicate flag, i am expecting a
>>> >>>> notification can be sent from peripheral to central automatically. It
>>> >>>>seems there is no such support in bluetoothctl.Then I do simple code
>>> >>>> change on below, and try to update value via "update-chrc 0x02",
>>> >>>> well,
>>> >>>> the value has been successfully updated, but there is no
>>> >>>> message/notification sent from peripheral to central automatically. I
>>> >>>> have confirmed that chrc read from central is showing updated value,
>>> >>>> 02, correctly.The question is that how can we send characteristic
>>> >>>> notification/indication using bluez dbus API?
>>> >>
>>> >> That is up for the application when to generate Value changes, we can
>>> >> introduce a command to just do that, though using bluetoothctl to
>>> >> generate notification is not very user friendly.
>>> >>
>>> >> bluetoothd will notice if the application had update its Value, but in
>>> >> order for this to work you have to generate the PropertiesChanged
>>> >> signal.
>>> >>
>>> >>>> btw,I see the video(BlueZ Meets Zephyr made by Luiz)
>>> >>>> https://www.youtube.com/watch?v=SdmZX5q-XDg
>>> >>>> In 30:05,I see Zephyr is sending notification to bluetoothctl
>>> >>>> automatically.How can we just use bluez dbus API to achieve this?
>>> >>
>>> >> That is using HRS and emulating the heart rate measurements.
>>> >>
>>> >>>> for example,
>>> >>>> In LE peripheral:
>>> >>>>I setup the below characteristic with read and indicate flag
>>> >>>> register-service 00001820-0000-1000-8000-00805f9b34fb
>>> >>>> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb
>>> >>>> read,indicate
>>> >>>> register-application
>>> >>>> advertise peripheral
>>> >>>>
>>> >>>> In LE central:
>>> >>>> connect 00:AA:01:00:00:23
>>> >>>> select-attribute
>>> >>>> /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
>>> >>>> notify on
>>> >>>>
>>> >>>> The code change snippet
>>> >>>> --- a/client/gatt.c
>>> >>>>+++ b/client/gatt.c
>>> >>>>-void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy,
>>> >>>> wordexp_t *w)
>>> >>>> +void chrc_set_value1(const char *input, void *user_data,
>>> >>>> DBusConnection *conn)
>>> >>>> +{
>>> >>>> +    struct chrc *chrc = user_data;
>>> >>>> +
>>> >>>> +    g_free(chrc->value);
>>> >>>> +
>>> >>>> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
>>> >>>> +    g_dbus_emit_property_changed(conn, chrc->path,
>>> >>>> "org.bluez.GattCharacteristic1", "Value");
>>> >>>> +
>>> >>>> +}
>>> >>>> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
>>> >>>> *proxy, wordexp_t *w)
>>> >>>>  {
>>> >>>>        struct service *service;
>>> >>>>         struct chrc *chrc;
>>> >>>> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
>>> >>>> GDBusProxy *proxy, wordexp_t *w)
>>> >>>>         print_chrc(chrc, COLORED_NEW);
>>> >>>>
>>> >>>>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value,
>>> >>>> chrc);
>>> >>>> +
>>> >>>> +    return chrc;
>>> >>>>  }
>>> >>>>
>>> >>>> --- a/client/main.c
>>> >>>> +++ b/client/main.c
>>> >>>>+static void cmd_update_chrc(const char *arg)
>>> >>>> +{
>>> >>>> +    chrc_set_value1(arg, default_chrc, dbus_conn);
>>> >>
>>> >>Where does default_chrc comes from? I guess we would need some way to
>>> >> select the server attributes in order to update them, again this is
>>> >> not going to be user friendly since you have to send the notification
>>> >> one by one. Perhaps an easier way to test this is to register standard
>>> >>attributes like HRS and enable simulation, so it would act exactly
>>> >> like zephyr or out example-gatt-server.
>>> >>
>>> >> This could perhaps be done automatically in case a know service is
>>> >> registered without any attributes, e.g: HRS, then by the time we
>>> >>register the application bluetoothctl would take care of registering
>>> >> the standard attributes for the service.
>>> >>
>>> >>>> +
>>> >>>> +}
>>> >>>> +
>>> >>>> static void cmd_unregister_characteristic(const char *arg)
>>> >>>>  {
>>> >>>>         wordexp_t w;
>>> >>>> @@ -2541,6 +2547,9 @@ static const struct {
>>> >>>>         { "register-characteristic", "<UUID>
>>> >>>> <Flags=read,write,notify...>",
>>> >>>>                                        cmd_register_characteristic,
>>> >>>>                                         "Register application
>>> >>>> characteristic" },
>>> >>>> +    { "update-chrc", "<value.>",
>>> >>>> +            cmd_update_chrc,
>>> >>>> +            "update chrc value" },
>>> >>>>
>>> >>>> Thanks
>>> >>>> Best wishes
>>> >>>> Yunhan
>>> >>> --
>>> >>>To unsubscribe from this list: send the line "unsubscribe
>>> >>> linux-bluetooth" in
>>> >>>the body of a message to majordomo@vger.kernel.org
>>> >>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> >>
>>> >>
>>> >>
>>> >> --
>>> >>Luiz Augusto of Dentz Luiz Augusto of Dentz
>>>
>>>
>>>
>>> -
>>
>>



-- 
Luiz Augusto von Dentz//vger.kernel.org/majordomo-info.html>>> >>>>>
>>>>> >>>>> >> -->>> >>Luiz Augusto of Dentz Luiz Augusto of
Dentz>>>>>>>>>>>> ->>>>-- Luiz Augusto von
Dentz//vger.kernel.org/majordomo-info.html>>> >>>>> >>>>> >>>>> >>
-->>> >>Luiz Augusto of Dentz Luiz Augusto of Dentz>>>>>>>>>>>>
->>>>-- Luiz Augusto von Dentz- Luiz Augusto of Dentz- Luiz Augusto of
Dentz

Re: bluetoothctl: how to send notification/indcation from peripheral to central

[Yunhan Wang]

Hi Luiz

The above diff is working now. Previously I accidentally create
multiple bluetoothd so that bluetoothd miss such signal.....I am
preparing the formal patch for this functionality in bluetoothctl.

Thanks
Best wishes
Yunhan

On Sun, Aug 6, 2017 at 1:25 AM, Yunhan Wang <yunhanw@nestlabs.com> wrote:
> Hi
>
> Has any one been able to send notification from LE peripheral to LE
> central using bluetoothctl?
>
> Now I am trying to update "Value" with 0x02 for the below
> characteristic with read and indicate flag, i am expecting a
> notification can be sent from peripheral to central automatically. It
> seems there is no such support in bluetoothctl. Then I do simple code
> change on below, and try to update value via "update-chrc 0x02", well,
> the value has been successfully updated, but there is no
> message/notification sent from peripheral to central automatically. I
> have confirmed that chrc read from central is showing updated value,
> 02, correctly. The question is that how can we send characteristic
> notification/indication using bluez dbus API?
>
> btw, I see the video(BlueZ Meets Zephyr made by Luiz)
> https://www.youtube.com/watch?v=SdmZX5q-XDg
> In 30:05, I see Zephyr is sending notification to bluetoothctl
> automatically. How can we just use bluez dbus API to achieve this?
>
> for example,
> In LE peripheral:
> I setup the below characteristic with read and indicate flag
> register-service 00001820-0000-1000-8000-00805f9b34fb
> register-characteristic 00002a06-0000-1000-8000-00805f9b34fb read,indicate
> register-application
> advertise peripheral
>
> In LE central:
> connect 00:AA:01:00:00:23
> select-attribute /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
> notify on
>
> The code change snippet
> --- a/client/gatt.c
> +++ b/client/gatt.c
> -void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
> +void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
> +{
> +    struct chrc *chrc = user_data;
> +
> +    g_free(chrc->value);
> +
> +    chrc->value = str2bytearray((char *) input, &chrc->value_len);
> +    g_dbus_emit_property_changed(conn, chrc->path,
> "org.bluez.GattCharacteristic1", "Value");
> +
> +}
> +struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
> *proxy, wordexp_t *w)
>  {
>         struct service *service;
>         struct chrc *chrc;
> @@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
> GDBusProxy *proxy, wordexp_t *w)
>         print_chrc(chrc, COLORED_NEW);
>
>         rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
> +
> +    return chrc;
>  }
>
> --- a/client/main.c
> +++ b/client/main.c
> +static void cmd_update_chrc(const char *arg)
> +{
> +    chrc_set_value1(arg, default_chrc, dbus_conn);
> +
> +}
> +
>  static void cmd_unregister_characteristic(const char *arg)
>  {
>         wordexp_t w;
> @@ -2541,6 +2547,9 @@ static const struct {
>         { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
>                                         cmd_register_characteristic,
>                                         "Register application characteristic" },
> +    { "update-chrc", "<value.>",
> +            cmd_update_chrc,
> +            "update chrc value" },
>
> Thanks
> Best wishes
> Yunhan

bluetoothctl: how to send notification/indcation from peripheral to central

[Yunhan Wang]

Hi

Has any one been able to send notification from LE peripheral to LE
central using bluetoothctl?

Now I am trying to update "Value" with 0x02 for the below
characteristic with read and indicate flag, i am expecting a
notification can be sent from peripheral to central automatically. It
seems there is no such support in bluetoothctl. Then I do simple code
change on below, and try to update value via "update-chrc 0x02", well,
the value has been successfully updated, but there is no
message/notification sent from peripheral to central automatically. I
have confirmed that chrc read from central is showing updated value,
02, correctly. The question is that how can we send characteristic
notification/indication using bluez dbus API?

btw, I see the video(BlueZ Meets Zephyr made by Luiz)
https://www.youtube.com/watch?v=SdmZX5q-XDg
In 30:05, I see Zephyr is sending notification to bluetoothctl
automatically. How can we just use bluez dbus API to achieve this?

for example,
In LE peripheral:
I setup the below characteristic with read and indicate flag
register-service 00001820-0000-1000-8000-00805f9b34fb
register-characteristic 00002a06-0000-1000-8000-00805f9b34fb read,indicate
register-application
advertise peripheral

In LE central:
connect 00:AA:01:00:00:23
select-attribute /org/bluez/hci1/dev_00_AA_01_00_00_23/service000a/char000b
notify on

The code change snippet
--- a/client/gatt.c
+++ b/client/gatt.c
-void gatt_register_chrc(DBusConnection *conn, GDBusProxy *proxy, wordexp_t *w)
+void chrc_set_value1(const char *input, void *user_data, DBusConnection *conn)
+{
+    struct chrc *chrc = user_data;
+
+    g_free(chrc->value);
+
+    chrc->value = str2bytearray((char *) input, &chrc->value_len);
+    g_dbus_emit_property_changed(conn, chrc->path,
"org.bluez.GattCharacteristic1", "Value");
+
+}
+struct chrc * gatt_register_chrc(DBusConnection *conn, GDBusProxy
*proxy, wordexp_t *w)
 {
        struct service *service;
        struct chrc *chrc;
@@ -1489,6 +1500,8 @@ void gatt_register_chrc(DBusConnection *conn,
GDBusProxy *proxy, wordexp_t *w)
        print_chrc(chrc, COLORED_NEW);

        rl_prompt_input(chrc->path, "Enter value:", chrc_set_value, chrc);
+
+    return chrc;
 }

--- a/client/main.c
+++ b/client/main.c
+static void cmd_update_chrc(const char *arg)
+{
+    chrc_set_value1(arg, default_chrc, dbus_conn);
+
+}
+
 static void cmd_unregister_characteristic(const char *arg)
 {
        wordexp_t w;
@@ -2541,6 +2547,9 @@ static const struct {
        { "register-characteristic", "<UUID> <Flags=read,write,notify...>",
                                        cmd_register_characteristic,
                                        "Register application characteristic" },
+    { "update-chrc", "<value.>",
+            cmd_update_chrc,
+            "update chrc value" },

Thanks
Best wishes
Yunhan