mumble/plugins/link/link.cpp

// Copyright 2007-2021 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>.

#ifndef QT_NO_DEBUG
#	include <stdio.h>
#	include <stdlib.h>
#endif
#include <windows.h>
#include <math.h>

#define MUMBLE_ALLOW_DEPRECATED_LEGACY_PLUGIN_API
#include "../mumble_legacy_plugin.h"

static std::wstring wsPluginName;
static std::wstring wsDescription;

struct LinkedMem {
	UINT32 uiVersion;
	DWORD dwcount;
	float fAvatarPosition[3];
	float fAvatarFront[3];
	float fAvatarTop[3];
	wchar_t name[256];
	float fCameraPosition[3];
	float fCameraFront[3];
	float fCameraTop[3];
	wchar_t identity[256];
	UINT32 context_len;
	unsigned char context[256];
	wchar_t description[2048];
};

static void about(void *h) {
	::MessageBox(reinterpret_cast< HWND >(h), L"Reads audio position information from linked game",
				 L"Mumble Link Plugin", MB_OK);
}

static HANDLE hMapObject = nullptr;
static LinkedMem *lm     = nullptr;
static DWORD last_count  = 0;
static DWORD last_tick   = 0;

static void unlock() {
	lm->dwcount = last_count = 0;
	lm->uiVersion            = 0;
	lm->name[0]              = 0;
	wsPluginName.assign(L"Link");
	wsDescription.clear();
}

static int trylock() {
	if ((lm->uiVersion == 1) || (lm->uiVersion == 2)) {
		if (lm->dwcount != last_count) {
			last_count = lm->dwcount;
			last_tick  = GetTickCount();

			errno_t err = 0;
			wchar_t buff[2048];

			if (lm->name[0]) {
				err = wcscpy_s(buff, 256, lm->name);
				if (!err)
					wsPluginName.assign(buff);
			}
			if (!err && lm->description[0]) {
				err = wcscpy_s(buff, 2048, lm->description);
				if (!err)
					wsDescription.assign(buff);
			}
			if (err) {
				wsPluginName.assign(L"Link");
				wsDescription.clear();
				return false;
			}
			return true;
		}
	}
	return false;
}


static int fetch(float *avatar_pos, float *avatar_front, float *avatar_top, float *camera_pos, float *camera_front,
				 float *camera_top, std::string &context, std::wstring &identity) {
	if (lm->dwcount != last_count) {
		last_count = lm->dwcount;
		last_tick  = GetTickCount();
	} else if ((GetTickCount() - last_tick) > 5000)
		return false;

	if ((lm->uiVersion != 1) && (lm->uiVersion != 2))
		return false;

	for (int i = 0; i < 3; ++i) {
		avatar_pos[i]   = lm->fAvatarPosition[i];
		avatar_front[i] = lm->fAvatarFront[i];
		avatar_top[i]   = lm->fAvatarTop[i];
	}

	if (lm->uiVersion == 2) {
		for (int i = 0; i < 3; ++i) {
			camera_pos[i]   = lm->fCameraPosition[i];
			camera_front[i] = lm->fCameraFront[i];
			camera_top[i]   = lm->fCameraTop[i];
		}

		if (lm->context_len > 255)
			lm->context_len = 255;
		lm->identity[255] = 0;

		context.assign(reinterpret_cast< const char * >(lm->context), lm->context_len);
		identity.assign(lm->identity);
	} else {
		for (int i = 0; i < 3; ++i) {
			camera_pos[i]   = lm->fAvatarPosition[i];
			camera_front[i] = lm->fAvatarFront[i];
			camera_top[i]   = lm->fAvatarTop[i];
		}
		context.clear();
		identity.clear();
	}

	return true;
}

static const std::wstring getdesc() {
	return wsDescription;
}

BOOL WINAPI DllMain(HINSTANCE, DWORD fdwReason, LPVOID) {
	bool bCreated = false;
	switch (fdwReason) {
		case DLL_PROCESS_ATTACH:
			wsPluginName.assign(L"Link");
			hMapObject = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, L"MumbleLink");
			if (!hMapObject) {
				hMapObject = CreateFileMapping(INVALID_HANDLE_VALUE, nullptr, PAGE_READWRITE, 0, sizeof(LinkedMem),
											   L"MumbleLink");
				bCreated   = true;
				if (!hMapObject)
					return false;
			}
			lm = static_cast< LinkedMem * >(MapViewOfFile(hMapObject, FILE_MAP_ALL_ACCESS, 0, 0, 0));
			if (!lm) {
				CloseHandle(hMapObject);
				hMapObject = nullptr;
				return false;
			}
			if (bCreated)
				memset(lm, 0, sizeof(LinkedMem));
			break;
		case DLL_PROCESS_DETACH:
			if (lm) {
				UnmapViewOfFile(lm);
				lm = nullptr;
			}
			if (hMapObject) {
				CloseHandle(hMapObject);
				hMapObject = nullptr;
			}
			break;
	}
	return true;
}

static std::wstring description(L"Link v1.2.0");

static MumblePlugin linkplug = {
	MUMBLE_PLUGIN_MAGIC, description, wsPluginName, about, nullptr, trylock, unlock, getdesc, fetch
};

extern "C" MUMBLE_PLUGIN_EXPORT MumblePlugin *getMumblePlugin() {
	return &linkplug;
}