GattLib is a library used to access Generic Attribute Profile (GATT) protocol of BLE (Bluetooth Low Energy) devices.

It is based on Bluez 4.101 GATT code (prior to Bluez D-BUS API).

It has been introduced to allow to build applications hosted on platform with a version of Bluez prior to v5.x that could easily communicate with BLE devices.

Potentially, D-BUS API could also be added to GattLib to provide an abstraction layer between different versions of BlueZ.

Build GattLib

cd <gattlib-src-root>
mkdir build && cd build
cmake ..
make

Package GattLib

From the build directory: cpack ..

Note: It generates DEB, RPM and ZIP packages. Ensure you have the expected dependencies installed on your system (eg: to generate RPM package on Debian-based Linux distribution you must have rpm package installed).

Default install directory is defined as /usr by CPack variable CPACK_PACKAGE_INSTALL_DIRECTORY.
To change the install directory to /usr/local run: cpack -DCPACK_PACKAGE_INSTALL_DIRECTORY=/usr/local ..

Examples

• Demonstrate discovering of primary services and characteristics:

    ./examples/discover/discover 78:A5:04:22:45:4F
  

• Demonstrate characteristic read/write:

    ./examples/read_write/read_write 78:A5:04:22:45:4F read 00002a29-0000-1000-8000-00805f9b34fb
    ./examples/read_write/read_write 78:A5:04:22:45:4F write 00002a6b-0000-1000-8000-00805f9b34fb 0x1234
  

Note: examples/gatttool has been partially ported to gattlib. There are two reasons the laziness (some of the GATT functions could be replaced by their gattlib equivalent) and the completeness (there are still some missing functions in gattlib).

• Notification is also supported. Example:

void notification_cb(uint16_t handle, const uint8_t* data, size_t data_length) {
	printf("Notification on handle 0x%02x : ", handle);
}

main() {
	uint16_t status_handle; // Handle of the 'status' characteristic
	uint16_t enable_notification = 0x0001;

	// Enable Status Notification
	gattlib_write_char_by_handle(connection, status_handle + 1, &enable_notification, sizeof(enable_notification));
	// Register notification handler
	gattlib_register_notification(notification_cb);
}

TODO List

• Complete examples/gatttool port to GattLib to demonstrate the completeness of GattLib.
• Support Bluez v5.x GATT D-BUS API in addition to the current Bluez v4.101 support.
• Remove GLib dependencies to GattLib (mainly replacing GLib IO Channels by Unix Domain Socket).