Godot SIP GDExtension (Godot 4.x)

This repository scaffolds a GDExtension that will embed SIP calling via PJSIP.

Status

• GDExtension skeleton is in place.
• PJSIP (pjsua) integration is wired for init, registration, calls, and audio device selection.
• Godot-facing API is active (SIPClient, SIPCall) with async signals from native callbacks.

License

This repository distributes binaries that link against pjproject (PJSIP).

• Distributed addon binaries and releases are licensed under GPL-2.0-or-later.
• The top-level LICENSE file contains the GNU GPL v2 text.
• pjproject is included as a submodule in thirdparty/pjsip/pjproject and keeps its own upstream licensing and notices.

If you need non-GPL distribution terms, use an appropriate commercial licensing path for pjproject and adjust this repository's distribution model accordingly.

Build prerequisites

• Godot 4.x headers via godot-cpp.
• PJSIP built for your target platform(s).
• CMake 3.22+ and a C++17 compiler.

Clone with submodules

This repository uses a git submodule for pjproject.

git clone --recurse-submodules <repo-url>

If you already cloned without submodules:

git submodule update --init --recursive

Quick build (all platforms)

1. Build godot-cpp for your target platform and note its path.
2. Build PJSIP and note its root path (contains pjlib/include).
3. Configure + build this project:

cmake -S . -B build \
  -DGODOT_CPP_PATH=/path/to/godot-cpp \
  -DPJSIP_PATH=/path/to/pjsip
cmake --build build --config Debug

The build outputs to build/bin/ with Godot-style names like:

• godot_sip.windows.debug.x86_64.dll
• godot_sip.linux.release.x86_64.so
• godot_sip.macos.release.arm64.dylib

Copy the resulting library to your Godot project bin/ folder and add godot_sip.gdextension to the project root.

Godot API

• SIPClient
  • initialize(user_agent: String) -> bool
  • register_account(sip_uri, username, password, registrar) -> bool
  • make_call(destination_uri: String) -> SIPCall
  • hangup_call(call: SIPCall)
  • answer_call(call: SIPCall)
  • reject_call(call: SIPCall)
  • get_audio_input_devices() -> PackedStringArray
  • get_audio_output_devices() -> PackedStringArray
  • select_audio_input_device(name: String) -> bool
  • select_audio_output_device(name: String) -> bool
  • registration_state_changed(state) signal
  • incoming_call(call) signal
  • call_state_changed(call, state) signal

Demo Scene

• Open demo/sip_demo.tscn in Godot.
• Fill account fields, then click Register.
• Enter destination URI and click Call.
• Use Answer, Reject, Hang Up for active/incoming calls.
• Pick audio devices from the dropdowns or refresh with Refresh Audio Devices.

Next steps

• Add call hold/resume, transfer, and DTMF APIs.
• Add transport options (TCP/TLS, custom SIP port, ICE/STUN/TURN config).
• Add platform packaging scripts to copy the right .dll/.so/.dylib into a Godot project automatically.