Re: [PATCH BlueZ 4/5] btgatt-client: Add function to search descriptors

[Frédéric Danis <frederic.danis@xxxxxxxxxxxxx>]

Hi Luiz,

On 22/01/2024 19:15, Luiz Augusto von Dentz wrote:
> Hi Frédéric,
>
> On Mon, Jan 22, 2024 at 12:43 PM Frédéric Danis
> <frederic.danis@xxxxxxxxxxxxx>  wrote:
> > This is requested to pass PTS GATT/CL/GAD/BV-06-C test.
> > This search descriptors based on start and end handles.
> Is this test mandatory though? Afaik if we do support the discovery of
> all procedure this becomes useless, because the stack can perform
> these operations locally by using its cache.
This test is optional, as tests GATT/CL/GAR/BI-10-C and 
GATT/CL/GAR/BI-11-C which also needs this patch to pass. 
GATT/CL/GAR/BI-10-C and GATT/CL/GAR/BI-11-C request the ability to 
prevent security upgrade. This may need to add a security retry flag to 
bt_gatt_read_by_type() in src/shared/gatt-helpers.{ch} to be able to 
call bt_att_set_retry() introduced in the first patch of this series. 
Does it seem correct?
> > ---
> >   tools/btgatt-client.c | 79 +++++++++++++++++++++++++++++++++++++++++++
> >   1 file changed, 79 insertions(+)
> >
> > diff --git a/tools/btgatt-client.c b/tools/btgatt-client.c
> > index bb0822658..a7d5d76ba 100644
> > --- a/tools/btgatt-client.c
> > +++ b/tools/btgatt-client.c
> > @@ -1490,6 +1490,83 @@ static void cmd_search_characteristics(struct client *cli, char *cmd_str)
> >                                                  NULL);
> >   }
> >
> > +static void search_descriptors_usage(void)
> > +{
> > +       printf("Usage: search-descriptors <start_hanlde> <end_handle>\n"
> > +               "e.g.:\n"
> > +               "\tsearch-descriptors 0x0001 0xFFFF\n");
> > +}
> > +
> > +static void search_descriptors_cb(bool success, uint8_t att_ecode,
> > +                                       struct bt_gatt_result *result,
> > +                                       void *user_data)
> > +{
> > +       struct bt_gatt_iter iter;
> > +       uint16_t handle;
> > +       uint128_t u128;
> > +       bt_uuid_t uuid;
> > +       char uuid_str[MAX_LEN_UUID_STR];
> > +
> > +       if (!success) {
> > +               PRLOG("\nDescriptors discovery failed: %s (0x%02x)\n",
> > +                               ecode_to_string(att_ecode), att_ecode);
> > +               return;
> > +       }
> > +
> > +       if (!result || !bt_gatt_iter_init(&iter, result))
> > +               return;
> > +
> > +       printf("\n");
> > +       while (bt_gatt_iter_next_descriptor(&iter, &handle, u128.data)) {
> > +               bt_uuid128_create(&uuid, u128);
> > +               bt_uuid_to_string(&uuid, uuid_str, sizeof(uuid_str));
> > +               printf("Found handle: 0x%04x UUID: %s\n", handle, uuid_str);
> > +       }
> > +       PRLOG("\n");
> > +}
> > +
> > +static void cmd_search_descriptors(struct client *cli, char *cmd_str)
> > +{
> > +       char *argv[3];
> > +       int argc = 0;
> > +       uint16_t start_handle, end_handle;
> > +       char *endptr = NULL;
> > +
> > +       if (!bt_gatt_client_is_ready(cli->gatt)) {
> > +               printf("GATT client not initialized\n");
> > +               return;
> > +       }
> > +
> > +       if (!parse_args(cmd_str, 2, argv, &argc)) {
> > +               printf("Too many arguments\n");
> > +               search_descriptors_usage();
> > +               return;
> > +       }
> > +
> > +       if (argc < 1) {
> > +               search_descriptors_usage();
> > +               return;
> > +       }
> > +
> > +       start_handle = strtol(argv[0], &endptr, 0);
> > +       if (!endptr || *endptr != '\0') {
> > +               printf("Invalid start handle: %s\n", argv[0]);
> > +               return;
> > +       }
> > +
> > +       end_handle = strtol(argv[1], &endptr, 0);
> > +       if (!endptr || *endptr != '\0') {
> > +               printf("Invalid end handle: %s\n", argv[1]);
> > +               return;
> > +       }
> > +
> > +       bt_gatt_discover_descriptors(bt_gatt_client_get_att(cli->gatt),
> > +                                               start_handle, end_handle,
> > +                                               search_descriptors_cb,
> > +                                               NULL,
> > +                                               NULL);
> > +}
> > +
> >   static void cmd_help(struct client *cli, char *cmd_str);
> >
> >   typedef void (*command_func_t)(struct client *cli, char *cmd_str);
> > @@ -1530,6 +1607,8 @@ static struct {
> >                                  "\tSearch service"},
> >          { "search-characteristics", cmd_search_characteristics,
> >                                  "\tSearch characteristics"},
> > +       { "search-descriptors", cmd_search_descriptors,
> > +                               "\tSearch descriptors"},
> >          { }
> >   };
> >
> > --
> > 2.34.1

--
Frédéric Danis
Senior Software Engineer

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