The Fuchsia Bluetooth system aims to provide a dual-mode implementation of the Bluetooth Host Subsystem (5.0+) supporting a framework for developing Low Energy and Traditional profiles.
Source code shortcuts:
For more orientation, see
Examples using Fuchsia's Bluetooth Low Energy APIs for all four LE roles can be found in Garnet and Topaz. All of these are currently compiled into Fuchsia by default.
eddystone_agent. This is a suggestion agent that proposes URL links that are obtained from Eddystone beacons. This is built in topaz by default.
eddystone_advertiser. This is a Flutter module that can advertise any entered URL as an Eddystone beacon.
Dual-mode (LE + Classic) GAP operations that are typically exposed to privileged clients are performed using the control.fidl API. This API is intended for managing local adapters, device discovery & discoverability, pairing/bonding, and other settings.
bt-cli is a command-line front-end for this API:
$ bt-cli bluetooth> list-adapters Adapter 0 id: bf004a8b-d691-4298-8c79-130b83e047a1 address: 00:1A:7D:DA:0A bluetooth>
See the bluetooth/tools package for more information on available command line tools for testing/debugging.
bluetooth_tests package contains Bluetooth test binaries. This package is defined in the tests BUILD file.
Host subsystem tests are compiled into a single GoogleTest binary, which gets installed at
Run all the tests:
$ runtests -t bt-host-unittests
Or use the
--gtest_filter flag to run a subset of the tests:
# This only runs the L2CAP unit tests. $ /pkgfs/packages/bluetooth_tests/0/test/bt-host-unittests --gtest_filter=L2CAP_*
(We specify the full path in this case, because runtests doesn't allow us to pass through arbitrary arguments to the test binary.)
And use the
--verbose flag to set log verbosity:
# This logs all messages logged using FXL_VLOG (up to level 2) $ /pkgfs/packages/bluetooth_tests/0/test/bt-host-unittests --verbose=2
If you don't have physical hardware available, you can run the tests in QEMU using the same commands as above. A couple of tips will help run the tests a little more quickly.
fx run -k
$ /pkgfs/packages/bluetooth_tests/0/test/bt-host-unittests --quiet=10
With these two tips, the full bt-host-unittests suite runs in ~2 seconds.
TODO(armansito): Describe integration tests
The most reliable way to enable higher log verbosity is with kernel command line parameters. These can be configured through the
fx set command:
fx set x64 --args="kernel_cmdline_files=[\"$FUCHSIA_DIR/kernel_cmdline.txt\"]"
Add the commands to the
$FUCHSIA_DIR/kernel_cmdline.txt, e.g. to enable full logging for the usb transport, intel hci and host drivers:
$ cat $FUCHSIA_DIR/kernel_cmdline.txt driver.bt_host.log=+trace,+spew,+info,+error,+warn driver.bt_hci_intel.log=+trace,+spew,+info,+error,+warn driver.bt_transport_usb.log=+trace,+info,+error,+warn
(Hci drivers other than Intel can also be set. Other hci drivers include
fx set writes these values into the image, so they will survive a restart.
For more detail on driver logging, see Zircon driver logging
The Bluetooth system service is invoked by sysmgr to resolve service requests. The mapping between environment service names and their handlers is defined in bin/sysmgr/config/services.config. Add the
--verbose option to the Bluetooth entries to increase verbosity, for example:
... "bluetooth::control::AdapterManager": [ "bluetooth", "--verbose=2" ], "bluetooth::gatt::Server": [ "bluetooth", "--verbose=2" ], "bluetooth::low_energy::Central": [ "bluetooth", "--verbose=2" ], "bluetooth::low_energy::Peripheral": [ "bluetooth", "--verbose=2" ], ...
The bthost driver currently uses the FXL logging system. To enable maximum log verbosity, set the
BT_DEBUG macro to
1 in drivers/bluetooth/host/driver.cc.