darwin: properly handle 16-bit UUIDs for service and characteristics #50
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…in the unique format used by macOS Signed-off-by: Ron Evans <ron@hybridgroup.com>
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Tested on both Catalina and Big Sur, so this seems ready to merge. |
| d.prph.DiscoverServices(cbuuids) | ||
| d.prph.DiscoverServices([]cbgo.UUID{}) |
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Why are you no longer passing the uuids slice to DiscoverServices? See the documentation:
Note
If the
servicesUUIDsparameter isnil, this method returns all of the peripheral’s available services. This is much slower than providing an array of service UUIDs to search for.
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It is not actually working, it seems. Not sure if that is because of cbgo or something else. I tried a whole bunch of different things but could not get it to work as documented.
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That is unfortunate. What if you put in a literal nil instead of []cbgo.UUID{}? (That's in fact semantically different, []cbgo.UUID{} is not equal to nil).
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Looking at the source of cbgo that is unlikely to have an effect. I'm working on a possible patch to cbgo.
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Never mind, I was confused.
This is indeed rather unfortunate. Maybe you can raise a bug at the cbgo repository?
| uuid[0] = 0x00000000 | ||
| uuid[1] = 0x00000000 | ||
| uuid[2] = 0x00000000 | ||
| uuid[3] = uint32(shortUUID) << 16 |
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If MacOS uses this nonstandard format, then 🤷
It's a bit weird though, as the Bluetooth specification has clearly specified how to encode 16-bit UUIDs in a 128-bit UUID. Other platforms use that standard.
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This is what is returned by cbgo, hence why I had to make these changes.
macOS does some various other things with anonymizing BLE info, but beats me why this is the case.
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One alternative to consider to the change to |
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I have submitted an issue into the cbgo repo @aykevl In the meantime, I would prefer to not make any further changes to this PR unless absolutely needed. We can work on macOS further in future iterations. |
This PR properly handles the 16-bit UUIDs for service and characteristics in the unique format used by macOS.