Return-Path: MIME-Version: 1.0 In-Reply-To: References: <1431696620-4762-1-git-send-email-luiz.dentz@gmail.com> Date: Tue, 19 May 2015 10:41:12 -0700 Message-ID: Subject: Re: [PATCH BlueZ] shared/ad: Replace data if already exists From: Marie Janssen To: Luiz Augusto von Dentz Cc: "linux-bluetooth@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Luiz, On Tue, May 19, 2015 at 10:35 AM, Luiz Augusto von Dentz wrote: > Hi Marie, > > On Tue, May 19, 2015 at 8:16 PM, Marie Janssen wrote: >> Hi Luiz, >> >> On Mon, May 18, 2015 at 4:14 AM, Luiz Augusto von Dentz >> wrote: >>> Hi Marie, >>> >>> On Fri, May 15, 2015 at 7:04 PM, Marie Janssen wrote: >>>> On Fri, May 15, 2015 at 9:02 AM, Marie Janssen wrote: >>>>> Hi Luiz, >>>>> >>>>> On Fri, May 15, 2015 at 6:30 AM, Luiz Augusto von Dentz >>>>> wrote: >>>>>> From: Luiz Augusto von Dentz >>>>>> >>>>>> If either manufacturer or service data already exist but the content >>>>>> is different replace with the new data. >>>>>> --- >>>>>> src/shared/ad.c | 43 ++++++++++++++++++++++++++++++++++++++----- >>>>>> 1 file changed, 38 insertions(+), 5 deletions(-) >>>>>> >>>>>> diff --git a/src/shared/ad.c b/src/shared/ad.c >>>>>> index 00d138d..dfc6b9a 100644 >>>>>> --- a/src/shared/ad.c >>>>>> +++ b/src/shared/ad.c >>>>>> @@ -431,6 +431,14 @@ void bt_ad_clear_service_uuid(struct bt_ad *ad) >>>>>> queue_remove_all(ad->service_uuids, NULL, NULL, free); >>>>>> } >>>>>> >>>>>> +static bool manufacturer_id_data_match(const void *data, const void *user_data) >>>>>> +{ >>>>>> + const struct bt_ad_manufacturer_data *m = data; >>>>>> + uint16_t id = PTR_TO_UINT(user_data); >>>>>> + >>>>>> + return m->manufacturer_id == id; >>>>>> +} >>>>>> + >>>>>> bool bt_ad_add_manufacturer_data(struct bt_ad *ad, uint16_t manufacturer_id, >>>>>> void *data, size_t len) >>>>>> { >>>>>> @@ -442,6 +450,17 @@ bool bt_ad_add_manufacturer_data(struct bt_ad *ad, uint16_t manufacturer_id, >>>>>> if (len > (MAX_ADV_DATA_LEN - 2 - sizeof(uint16_t))) >>>>>> return false; >>>>>> >>>>>> + new_data = queue_find(ad->manufacturer_data, manufacturer_id_data_match, >>>>>> + UINT_TO_PTR(manufacturer_id)); >>>>>> + if (new_data) { >>>>>> + if (new_data->len == len && !memcmp(new_data->data, data, len)) >>>>>> + return false; >>>>> >>>>> I don't think we want this check. If the data is different but length >>>>> the same, we still want to update the data. >>>> >>>> Sorry I read this wrong. We would want to return true here because >>>> the data in the ad is as expected. >>> >>> This is to prevent emitting duplicated signals since in fact it did >>> not change anything. >>> >> >> Previously the false return value meant that some error had occurred, >> such as memory allocation failure or the data being too long for the >> ad. Having nothing change and the ad be basically intact seems like >> not a problem. I guess this is a API semantics question, whether a >> true return value means "the data is set correctly" vs "the data is >> updated". > > While this is true there is also the convenience side of things, lets > say we return true then I will need to check if the same data exists > before calling this function because otherwise I can't tell if > anything has changed and that basically means we have 2 checks instead > of one. Beside the action here is to some data, if we are not adding > or replacing anything Id say returning false is fine, btw if you look > at the blocks Im removing that is already the behavior we have. > All right, this makes sense then I don't have any problems with it otherwise. >>>>>> + new_data->data = realloc(new_data->data, len); >>>>>> + memcpy(new_data->data, data, len); >>>>>> + new_data->len = len; >>>>>> + return true; >>>>>> + } >>>>>> + >>>>>> new_data = new0(struct bt_ad_manufacturer_data, 1); >>>>>> if (!new_data) >>>>>> return false; >>>>>> @@ -458,11 +477,6 @@ bool bt_ad_add_manufacturer_data(struct bt_ad *ad, uint16_t manufacturer_id, >>>>>> >>>>>> new_data->len = len; >>>>>> >>>>>> - if (bt_ad_has_manufacturer_data(ad, new_data)) { >>>>>> - manuf_destroy(new_data); >>>>>> - return false; >>>>>> - } >>>>>> - >>>>>> if (queue_push_tail(ad->manufacturer_data, new_data)) >>>>>> return true; >>>>>> >>>>>> @@ -556,6 +570,15 @@ void bt_ad_clear_solicit_uuid(struct bt_ad *ad) >>>>>> queue_remove_all(ad->solicit_uuids, NULL, NULL, free); >>>>>> } >>>>>> >>>>>> + >>>>>> +static bool service_uuid_match(const void *data, const void *user_data) >>>>>> +{ >>>>>> + const struct bt_ad_service_data *s = data; >>>>>> + const bt_uuid_t *uuid = user_data; >>>>>> + >>>>>> + return bt_uuid_cmp(&s->uuid, uuid); >>>>>> +} >>>>>> + >>>>>> bool bt_ad_add_service_data(struct bt_ad *ad, const bt_uuid_t *uuid, void *data, >>>>>> size_t len) >>>>>> { >>>>>> @@ -567,6 +590,16 @@ bool bt_ad_add_service_data(struct bt_ad *ad, const bt_uuid_t *uuid, void *data, >>>>>> if (len > (MAX_ADV_DATA_LEN - 2 - (size_t)bt_uuid_len(uuid))) >>>>>> return false; >>>>>> >>>>>> + new_data = queue_find(ad->service_uuids, service_uuid_match, uuid); >>>>>> + if (new_data) { >>>>>> + if (new_data->len == len && !memcmp(new_data->data, data, len)) >>>>>> + return false; >>>>> >>>>> Similarly here as from above, it would be better to replace the data. >>>>> >>>>>> + new_data->data = realloc(new_data->data, len); >>>>>> + memcpy(new_data->data, data, len); >>>>>> + new_data->len = len; >>>>>> + return true; >>>>>> + } >>>>>> + >>>>>> new_data = new0(struct bt_ad_service_data, 1); >>>>>> if (!new_data) >>>>>> return false; >>>>>> -- >>>>>> 2.1.0 >>>>>> >>>>>> -- >>>>>> 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 >>>>> >>>>> >>>>> >>>>> -- >>>>> Marie Janssen >>> >>> >>> >>> -- >>> Luiz Augusto von Dentz >> >> >> >> -- >> Marie Janssen > > > > -- > Luiz Augusto von Dentz -- Marie Janssen