MAINT: Add Link plugin tester

This commit adds a small CLI program that just connects to the Link
plugin and sends random positions to it. It is meant to be used as a
test-case for the Link plugin.

2 files changed, 121 insertions, 0 deletions

diff --git a/plugins/link/CMakeLists.txt b/plugins/link/CMakeLists.txt
index 146657f89..83ea8d435 100644
--- a/plugins/link/CMakeLists.txt
+++ b/plugins/link/CMakeLists.txt
@@ -8,9 +8,18 @@ add_library(link SHARED
 	"SharedMemory.cpp"
 )
 
+add_executable(link_tester
+	"link_tester.cpp"
+	"SharedMemory.cpp"
+)
+
 if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
 	find_library(LIB_RT "rt")
 	target_link_libraries(link PRIVATE ${LIB_RT})
+	target_link_libraries(link_tester PRIVATE ${LIB_RT})
 endif()
 
 target_include_directories(link PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
+target_include_directories(link_tester PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
+
+set_target_properties(link_tester PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}")
diff --git a/plugins/link/link_tester.cpp b/plugins/link/link_tester.cpp
new file mode 100644
index 000000000..c8edd5ea2
--- /dev/null
+++ b/plugins/link/link_tester.cpp
@@ -0,0 +1,112 @@
+// Copyright 2021 The Mumble Developers. All rights reserved.
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file at the root of the
+// Mumble source tree or at <https://www.mumble.info/LICENSE>.
+
+#include "LinkedMem.h"
+#include "SharedMemory.h"
+
+#ifndef _WIN32
+#	include <unistd.h>
+#endif
+
+#include <chrono>
+#include <csignal>
+#include <cstring>
+#include <cwchar>
+#include <iostream>
+#include <random>
+#include <thread>
+
+SharedMemory sharedMem;
+LinkedMem *lm = nullptr;
+std::random_device dev;
+std::mt19937 rng(dev());
+std::uniform_real_distribution< float > generator(0, 100);
+
+void initMumble() {
+	lm = static_cast< LinkedMem * >(sharedMem.mapMemory(getLinkedMemoryName(), sizeof(LinkedMem)));
+}
+
+void updateMumble() {
+	if (!lm)
+		return;
+
+	if (lm->uiVersion != 2) {
+		wcsncpy(lm->name, L"TestLink", 256);
+		wcsncpy(lm->description, L"TestLink is a test of the Link plugin.", 2048);
+		lm->uiVersion = 2;
+	}
+	lm->uiTick++;
+
+	// Left handed coordinate system.
+	// X positive towards "right".
+	// Y positive towards "up".
+	// Z positive towards "front".
+	//
+	// 1 unit = 1 meter
+
+	// Unit vector pointing out of the avatar's eyes aka "At"-vector.
+	lm->fAvatarFront[0] = 0.0f;
+	lm->fAvatarFront[1] = 0.0f;
+	lm->fAvatarFront[2] = 1.0f;
+
+	// Unit vector pointing out of the top of the avatar's head aka "Up"-vector (here Top points straight up).
+	lm->fAvatarTop[0] = 0.0f;
+	lm->fAvatarTop[1] = 1.0f;
+	lm->fAvatarTop[2] = 0.0f;
+
+	// Position of the avatar (here standing slightly off the origin)
+	lm->fAvatarPosition[0] = generator(rng);
+	lm->fAvatarPosition[1] = generator(rng);
+	lm->fAvatarPosition[2] = generator(rng);
+
+	// Same as avatar but for the camera.
+	lm->fCameraPosition[0] = 0.0f;
+	lm->fCameraPosition[1] = 0.0f;
+	lm->fCameraPosition[2] = 0.0f;
+
+	lm->fCameraFront[0] = 0.0f;
+	lm->fCameraFront[1] = 0.0f;
+	lm->fCameraFront[2] = 1.0f;
+
+	lm->fCameraTop[0] = 0.0f;
+	lm->fCameraTop[1] = 1.0f;
+	lm->fCameraTop[2] = 0.0f;
+
+	// Identifier which uniquely identifies a certain player in a context (e.g. the ingame name).
+	wcsncpy(lm->identity, L"Unique ID", 256);
+	// Context should be equal for players which should be able to hear each other positional and
+	// differ for those who shouldn't (e.g. it could contain the server+port and team)
+	memcpy(lm->context, "ContextBlob\x00\x01\x02\x03\x04", 16);
+	lm->context_len = 16;
+}
+
+void signalHandler(int signum) {
+	std::cout << "Interrupt signal (" << signum << ") received - shutting down..." << std::endl;
+
+	lm = nullptr;
+	sharedMem.close();
+
+	std::exit(signum);
+}
+
+int main() {
+	signal(SIGINT, signalHandler);
+
+	initMumble();
+
+	if (!lm) {
+		std::cerr << "Failed to create shared memory region (" << sharedMem.lastError() << ")" << std::endl;
+		return 1;
+	}
+
+	std::cout << "Shared memory created successfully - Now starting update loop" << std::endl;
+
+	while (true) {
+		std::cout << "Tick" << std::endl;
+		updateMumble();
+
+		std::this_thread::sleep_for(std::chrono::milliseconds(500));
+	}
+}