Using the library in your project

This library requires you to enable C++17 (or above) and is developed for ESP-IDF. If you are using another framework, e.g. Arduino, or a different C++ version, it might work, or it might not, but you are on your own.
On ESP32, BLE needs to be enabled (and possibly pinned to a core). So make sure that your sdkconfig.defaults contains the following lines:
CONFIG_BT_ENABLED=y

CONFIG_BTDM_CTRL_MODE_BLE_ONLY=y

CONFIG_BTDM_CTRL_MODE_BR_EDR_ONLY=n

CONFIG_BTDM_CTRL_MODE_BTDM=n

CONFIG_BT_BLUEDROID_ENABLED=n

CONFIG_BT_NIMBLE_ENABLED=y

CONFIG_BT_NIMBLE_PINNED_TO_CORE_1=y
Make sure you have enabled C++17. For ESP-IDF, this requires to unset C++11 and C++17. In your platformio.ini:
[env:your_env]

platform = espressif32

framework = espidf

; ...

build_unflags = -std=gnu++11 -std=gnu++14 -std=c++11 -std=c++14 -std=c++17

; You can add more flags, but GNU++17 must be present

build_flags = -std=gnu++17
Check that your app compiles with these settings, first, using pio run or pio test. If it does,
add to platformio.ini the dependency on libGulliBLE:
[env:your_env]

; ... all the above flags, plus:

lib_deps = 5p4k/libGulliBLE
You can now use libGulliBLE. The includes are in the subfolder ble/, and the objects in the corresponding ble namespaces. You should check out some of the examples to get started, as you will need to piece together several things to get everything running.

Developer guide

Folder structure

Important folders:

libgullible/
Library source code, divided in headers, source code, examples.
- libgullible/{include, src, examples}/ble/
  All sources are placed in the subfolder ble. This reflects the namespace in which all the objects are located, and keeps the includes clean.
- libgullible/examples/sdkconfig.defaults
  This is the default ESP-IDF SDK config file that should be used when building the examples.
tests/
Subfolder containing the unit test project.
- tests/lib/libgullible/
  Symlink to libgullible/, to allow the unit tests to pick up the local library folder
- tests/test/.keep
  We need to keep this folder for PlatformIO to believe we are providing unit test in our own custom entry point.

Secondary folders:

cicd/ Helper files needed by CI/CD
docs/ Doxygen config and additional doxygen sources
misc/ Helper files needed for setting up development, logos, non-source material.

Setting up development

0. Install PlatformIO CLI.

Prepare tests/platformio.ini. You can, for example
- Customize tests/platformio.ini.sample to your board and setup, or
- Copy cicd/platformio.ini, the file used by CI/CD
Generate a compilation database for your IDE of choice using
$> ./misc/gen-compiledb.py tests/platformio.ini

You have to regenerate this when a new file is added.
You are now using the unit test project to "host" the library (so you will see all usages of instantiated templates, for example).
Use the provided .clang-format file to format the source, e.g. by
$> clang-format --style file -i libgullible/src/ble/my_file.cpp

Running the tests

Note on the test project structure. We set up the unit test project in such a way that we can use both pio run and pio test to run the unit tests. The two commands are similar but different enough that some commands are available for one and not the other (for example, the compilation database is generated for pio run but not pio test). We work around this by providing a test transport (similar to the one provided by pio test), our own app_main() function and building sources and tests together.

0. Make sure you have setup your tests/platformio.ini as above.

Change directory and use either pio test or pio run, as follows:
$> cd tests/

$> pio run -t upload -t monitor # or

$> pio test

Building the documentation

Install Doxygen (or run through Docker), and run
$> doxygen ./doxygen.conf
The documentation can be seen at ./docs/_build/html/index.html.