Hi Luiz,
> -----Original Message-----
> From: Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx>
> Sent: Friday, June 5, 2020 10:32 PM
> To: Singh, AmitX K <amitx.k.singh@xxxxxxxxx>
> Cc: linux-bluetooth@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] bluetoothctl:Add support for read characteristics value
>
> Hi Amit,
>
> On Fri, Jun 5, 2020 at 7:30 AM Amitsi5x <amitx.k.singh@xxxxxxxxx> wrote:
> >
> > From: amit <amitx.k.singh@xxxxxxxxx>
> >
> > Changes made to add support for read charateristic value by uuid in
> > bluetoothctl.
> >
> > Signed-off-by: amit <amitx.k.singh@xxxxxxxxx>
> > ---
> > client/gatt.c | 70 ++++++++++++++++++++++++++++++++
> > client/gatt.h | 1 +
> > client/main.c | 18 +++++++++
> > src/gatt-client.c | 70 ++++++++++++++++++++++++++++++++
> > src/shared/gatt-client.c | 86
> > +++++++++++++++++++++++++++++++++++++++-
> > src/shared/gatt-client.h | 5 +++
> > 6 files changed, 249 insertions(+), 1 deletion(-)
> >
> > diff --git a/client/gatt.c b/client/gatt.c index 53f875050..8c2844ed6
> > 100644
> > --- a/client/gatt.c
> > +++ b/client/gatt.c
> > @@ -681,6 +681,76 @@ void gatt_read_attribute(GDBusProxy *proxy, int
> argc, char *argv[])
> > return bt_shell_noninteractive_quit(EXIT_FAILURE);
> > }
> >
> > +static void charreadbyuuid_reply(DBusMessage *message, void
> > +*user_data) {
> > + DBusError error;
> > + DBusMessageIter iter, array;
> > + uint8_t *value;
> > + int len;
> > +
> > + dbus_error_init(&error);
> > +
> > + if (dbus_set_error_from_message(&error, message) == TRUE) {
> > + bt_shell_printf("Failed to read: %s\n", error.name);
> > + dbus_error_free(&error);
> > + return bt_shell_noninteractive_quit(EXIT_FAILURE);
> > + }
> > +
> > + dbus_message_iter_init(message, &iter);
> > +
> > + if (dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY) {
> > + bt_shell_printf("Invalid response to read\n");
> > + return bt_shell_noninteractive_quit(EXIT_FAILURE);
> > + }
> > +
> > + dbus_message_iter_recurse(&iter, &array);
> > + dbus_message_iter_get_fixed_array(&array, &value, &len);
> > +
> > + if (len < 0) {
> > + bt_shell_printf("Unable to parse value\n");
> > + return bt_shell_noninteractive_quit(EXIT_FAILURE);
> > + }
> > +
> > + bt_shell_hexdump(value, len);
> > +
> > + return bt_shell_noninteractive_quit(EXIT_SUCCESS);
> > +}
> > +
> > +static void charreadbyuuid_setup(DBusMessageIter *iter, void
> > +*user_data) {
> > + char *uuid = user_data;
> > +
> > + dbus_message_iter_append_basic(iter, DBUS_TYPE_STRING, &uuid);
> > +}
> > +
> > +static void charreadbyuuid_attribute(GDBusProxy *proxy, char *uuid) {
> > + if (g_dbus_proxy_method_call(proxy, "CharReadByUUID",
> charreadbyuuid_setup, charreadbyuuid_reply,
> > + uuid, NULL) == FALSE) {
> > + bt_shell_printf("Failed to set uuid\n");
> > + return bt_shell_noninteractive_quit(EXIT_FAILURE);
> > + }
> > +
> > + bt_shell_printf("Attempting to read service handle %s\n",
> > +g_dbus_proxy_get_path(proxy)); }
> > +
> > +void gatt_charreadbyuuid_attribute(GDBusProxy *proxy, int argc, char
> > +*argv[]) {
> > + const char *iface;
> > +
> > + iface = g_dbus_proxy_get_interface(proxy);
> > +
> > + if (!strcmp(iface, "org.bluez.GattCharacteristic1")) {
> > + charreadbyuuid_attribute(proxy, argv[1]);
> > + return;
> > + }
> > +
> > + bt_shell_printf("Unable to read attribute %s\n",
> > +
> > + g_dbus_proxy_get_path(proxy));
> > +
> > + return bt_shell_noninteractive_quit(EXIT_FAILURE);
> > +}
> > +
> > static void charbyuuid_reply(DBusMessage *message, void *user_data)
> > {
> > DBusError error;
> > diff --git a/client/gatt.h b/client/gatt.h index 692fb5758..8f96d8665
> > 100644
> > --- a/client/gatt.h
> > +++ b/client/gatt.h
> > @@ -35,6 +35,7 @@ GDBusProxy *gatt_select_attribute(GDBusProxy
> > *parent, const char *path); char *gatt_attribute_generator(const char
> > *text, int state); void gatt_servbyuuid_attribute(GDBusProxy *proxy,
> > int argc, char *argv[]); void gatt_charbyuuid_attribute(GDBusProxy
> > *proxy, int argc, char *argv[]);
> > +void gatt_charreadbyuuid_attribute(GDBusProxy *proxy, int argc, char
> > +*argv[]);
> > void gatt_read_attribute(GDBusProxy *proxy, int argc, char *argv[]);
> > void gatt_write_attribute(GDBusProxy *proxy, int argc, char *argv[]);
> > void gatt_notify_attribute(GDBusProxy *proxy, bool enable); diff --git
> > a/client/main.c b/client/main.c index 10e64e17b..4dd1e593a 100644
> > --- a/client/main.c
> > +++ b/client/main.c
> > @@ -2071,6 +2071,22 @@ static void cmd_attribute_info(int argc, char
> *argv[])
> > return bt_shell_noninteractive_quit(EXIT_SUCCESS);
> > }
> >
> > +static void cmd_char_read_by_uuid(int argc, char *argv[]) {
> > + GDBusProxy *proxy;
> > +
> > + proxy = find_attribute(argc, argv);
> > +
> > + set_default_attribute(proxy);
> > +
> > + if (!default_attr) {
> > + bt_shell_printf("No attribute selected\n");
> > + return bt_shell_noninteractive_quit(EXIT_FAILURE);
> > + }
> > +
> > + gatt_charreadbyuuid_attribute(default_attr, argc, argv); }
> > +
> > static void cmd_char_by_uuid(int argc, char *argv[]) {
> > GDBusProxy *proxy;
> > @@ -2718,6 +2734,8 @@ static const struct bt_shell_menu gatt_menu = {
> > "Discover Primary Services by UUID" },
> > { "char-by-uuid", "[UUID]", cmd_char_by_uuid,
> > "Discover Characteristic Services by
> > UUID" },
> > + { "char-read-by-uuid", "[UUID]", cmd_char_read_by_uuid,
> > + "Read Characteristic by UUID" },
> > { "select-attribute", "<attribute/UUID>", cmd_select_attribute,
> > "Select attribute", attribute_generator },
> > { "attribute-info", "[attribute/UUID]", cmd_attribute_info,
> > diff --git a/src/gatt-client.c b/src/gatt-client.c index
> > da811ea4f..cd6d6dfde 100644
> > --- a/src/gatt-client.c
> > +++ b/src/gatt-client.c
> > @@ -444,6 +444,27 @@ static struct async_dbus_op
> *async_dbus_op_new(DBusMessage *msg, void *data)
> > return op;
> > }
> >
> > +static struct async_dbus_op *fetch_char_read_by_uuid(struct
> bt_gatt_client *gatt,
> > + DBusMessage *msg,
> > + char *uuid,
> > + bt_gatt_client_char_by_uuid_callback_t callback,
> > + void *data) {
> > + struct async_dbus_op *op;
> > +
> > + op = async_dbus_op_new(msg, data);
> > + op->id = bt_gatt_client_char_read_by_uuid(gatt, uuid, callback,
> > + async_dbus_op_ref(op),
> > + async_dbus_op_unref);
> > +
> > + if (op->id)
> > + return op;
> > +
> > + async_dbus_op_free(op);
> > +
> > + return NULL;
> > +}
> > +
> > static struct async_dbus_op *fetch_char_by_uuid(struct bt_gatt_client
> *gatt,
> > DBusMessage *msg,
> > char *uuid, @@ -972,6 +993,52
> > @@ fail:
> > chrc->read_op = NULL;
> > }
> >
> > +static void char_read_by_uuid_cb(bool success, uint8_t att_ecode, const
> uint8_t *value,
> > + uint16_t length, void
> > +*user_data) {
> > + struct async_dbus_op *op = user_data;
> > + struct characteristic *opchar = op->data;
> > +
> > + if (!success)
> > + goto fail;
> > +
> > + async_dbus_op_reply(op, att_ecode, value, length);
> > +
> > + return;
> > +
> > +fail:
> > + async_dbus_op_reply(op, att_ecode, NULL, 0);
> > +
> > + opchar->type_op = NULL;
> > +}
> > +
> > +static DBusMessage *char_read_by_uuid(DBusConnection *conn,
> > + DBusMessage *msg, void
> > +*user_data) {
> > + struct characteristic *chardata = user_data;
> > + struct bt_gatt_client *gatt = chardata->service->client->gatt;
> > + DBusMessageIter iter;
> > +
> > + char *uuid = 0;
> > +
> > + if (!gatt)
> > + return btd_error_failed(msg, "Not connected");
> > +
> > + dbus_message_iter_init(msg, &iter);
> > +
> > + if (dbus_message_iter_get_arg_type(&iter) == DBUS_TYPE_STRING)
> > + dbus_message_iter_get_basic(&iter,&uuid);
> > + else
> > + return NULL;
> > +
> > + chardata->type_op = fetch_char_read_by_uuid(gatt, msg,uuid,
> > + char_read_by_uuid_cb, chardata);
> > +
> > + if (!chardata->type_op)
> > + return btd_error_failed(msg, "Failed to send read
> > + request");
> > +
> > + return NULL;
> > +}
> > +
> > static void characteristic_by_uuid_cb(bool success, uint8_t att_ecode,
> const uint8_t *value,
> > uint16_t length, void
> > *user_data) { @@ -1786,6 +1853,9 @@ static const GDBusMethodTable
> > characteristic_methods[] = {
> > { GDBUS_ASYNC_METHOD("CharByUUID", GDBUS_ARGS({ "options",
> "s" }),
> > GDBUS_ARGS({ "value", "ay" }),
> > chardiscover_by_uuid) },
> > + { GDBUS_ASYNC_METHOD("CharReadByUUID", GDBUS_ARGS({
> "options", "s" }),
> > + GDBUS_ARGS({ "value", "ay" }),
> > + char_read_by_uuid) },
>
> It would have helped if you had communicated that you would be looking
> into add support for this type of operation, these procedures obviously
> cannot be part of Characteristic interface since that is only available after the
> discovery procedure then you can just lookup internally in the cache. So this
> type of procedure will probably need to be under a Device object and lets
> please agree on the documentation first before we move forward.
>
When we verify the PTS test case GATT/CL/GAR/BV-03-C "Read using characterisitic UUID", the Test case expect read request from device .
Added a code for sending read request for reading characteristic value using UUID over characteristic interface
> > { GDBUS_ASYNC_METHOD("ReadValue", GDBUS_ARGS({ "options",
> "a{sv}" }),
> > GDBUS_ARGS({ "value", "ay" }),
> > characteristic_read_value) },
> > diff --git a/src/shared/gatt-client.c b/src/shared/gatt-client.c index
> > 8a696c77f..7c9d25ec3 100644
> > --- a/src/shared/gatt-client.c
> > +++ b/src/shared/gatt-client.c
> > @@ -2725,6 +2725,90 @@ done:
> > op->callback(success, att_ecode, value, length,
> > op->user_data); }
> >
> > +unsigned int bt_gatt_client_char_read_by_uuid(struct bt_gatt_client
> *client,
> > + char *uuid,
> > + bt_gatt_client_char_by_uuid_callback_t callback,
> > + void *user_data,
> > +
> > +bt_gatt_client_destroy_func_t destroy) {
> > + struct request *req;
> > + struct char_by_uuid_op *op;
> > + unsigned char *pdu;
> > + uint16_t len ;
> > + uint16_t start_handle = 0x0001;
> > + uint16_t end_handle = 0xffff;
> > + bt_uuid_t btuuid;
> > + uint8_t uuid128[16];
> > +
> > + /* Length of pdu will be vary according to uuid type
> > + for 2 byte uuid total length is 8 (start handle(2) + end handle(2) +
> uuid(2))
> > + for 16 byte uuid total length is 22 (start handle(2) + end handle(2) +
> uuid(16))
> > + */
> > + uint16_t pdu_len_16bit_uuid = 6;
> > + uint16_t pdu_len_128bit_uuid = 20;
> > +
> > + if (bt_string_to_uuid(&btuuid, uuid) < 0) {
> > + return 0;
> > + }
> > +
> > + if (btuuid.type == BT_UUID16){
> > + pdu = (unsigned char *) malloc(pdu_len_16bit_uuid);
> > + len = pdu_len_16bit_uuid;
> > + } else {
> > + pdu = (unsigned char *) malloc(pdu_len_128bit_uuid);
> > + len = pdu_len_128bit_uuid;
> > + }
> > +
> > + if (!client)
> > + return 0;
> > +
> > + op = new0(struct char_by_uuid_op, 1);
> > + req = request_create(client);
> > + if (!req) {
> > + free(op);
> > + return 0;
> > + }
> > + if (!client)
> > + return 0;
> > +
> > + op = new0(struct char_by_uuid_op, 1);
> > + req = request_create(client);
> > +
> > + if (!req) {
> > + free(op);
> > + return 0;
> > + }
> > +
> > + op->callback = callback;
> > + op->user_data = user_data;
> > + op->destroy = destroy;
> > + req->data = op;
> > + req->destroy = destroy_char_by_uuid_op;
> > +
> > + put_le16(start_handle, pdu);
> > + put_le16(end_handle, pdu+2);
> > +
> > + if (btuuid.type == BT_UUID16)
> > + put_le16(btuuid.value.u16, pdu+4);
> > + else {
> > + bswap_128(&btuuid.value.u128.data[0], &uuid128[0]);
> > + memcpy(pdu + 4, uuid128, 16);
> > + }
> > +
> > + req->att_id = bt_att_send(client->att,
> BT_ATT_OP_READ_BY_TYPE_REQ,
> > + pdu, len,
> > + char_by_uuid_cb, req,
> > +
> > + request_unref);
> > +
> > + if (!req->att_id) {
> > + op->destroy = NULL;
> > + request_unref(req);
> > + return 0;
> > + }
> > +
> > + return req->id;
> > +}
> > +
> > unsigned int bt_gatt_client_char_by_uuid(struct bt_gatt_client *client,
> > char *uuid,
> >
> > bt_gatt_client_char_by_uuid_callback_t callback, @@ -2754,7 +2838,7 @@
> unsigned int bt_gatt_client_char_by_uuid(struct bt_gatt_client *client,
> > if (btuuid.type == BT_UUID16){
> > pdu = (unsigned char *) malloc(pdu_len_16bit_uuid);
> > len = pdu_len_16bit_uuid;
> > - } else {
> > + }else {
> > pdu = (unsigned char *) malloc(pdu_len_128bit_uuid);
> > len = pdu_len_128bit_uuid;
> > }
> > diff --git a/src/shared/gatt-client.h b/src/shared/gatt-client.h index
> > f5d5169ce..50859ce52 100644
> > --- a/src/shared/gatt-client.h
> > +++ b/src/shared/gatt-client.h
> > @@ -97,6 +97,11 @@ unsigned int bt_gatt_client_char_by_uuid(struct
> bt_gatt_client *client,
> > bt_gatt_client_read_callback_t callback,
> > void *user_data,
> > bt_gatt_client_destroy_func_t
> > destroy);
> > +unsigned int bt_gatt_client_char_read_by_uuid(struct bt_gatt_client
> *client,
> > + char *uuid,
> > + bt_gatt_client_read_callback_t callback,
> > + void *user_data,
> > + bt_gatt_client_destroy_func_t
> > +destroy);
> > unsigned int bt_gatt_client_read_value(struct bt_gatt_client *client,
> > uint16_t value_handle,
> > bt_gatt_client_read_callback_t
> > callback,
> > --
> > 2.17.1
> >
>
>
> --
> Luiz Augusto von Dentz
