pineapple-src/externals/discord-rpc/src/discord_rpc.cpp
2021-06-18 22:05:25 +02:00

504 lines
16 KiB
C++
Executable file

#include "discord_rpc.h"
#include "backoff.h"
#include "discord_register.h"
#include "msg_queue.h"
#include "rpc_connection.h"
#include "serialization.h"
#include <atomic>
#include <chrono>
#include <mutex>
#ifndef DISCORD_DISABLE_IO_THREAD
#include <condition_variable>
#include <thread>
#endif
constexpr size_t MaxMessageSize{16 * 1024};
constexpr size_t MessageQueueSize{8};
constexpr size_t JoinQueueSize{8};
struct QueuedMessage {
size_t length;
char buffer[MaxMessageSize];
void Copy(const QueuedMessage& other)
{
length = other.length;
if (length) {
memcpy(buffer, other.buffer, length);
}
}
};
struct User {
// snowflake (64bit int), turned into a ascii decimal string, at most 20 chars +1 null
// terminator = 21
char userId[32];
// 32 unicode glyphs is max name size => 4 bytes per glyph in the worst case, +1 for null
// terminator = 129
char username[344];
// 4 decimal digits + 1 null terminator = 5
char discriminator[8];
// optional 'a_' + md5 hex digest (32 bytes) + null terminator = 35
char avatar[128];
// Rounded way up because I'm paranoid about games breaking from future changes in these sizes
};
static RpcConnection* Connection{nullptr};
static DiscordEventHandlers QueuedHandlers{};
static DiscordEventHandlers Handlers{};
static std::atomic_bool WasJustConnected{false};
static std::atomic_bool WasJustDisconnected{false};
static std::atomic_bool GotErrorMessage{false};
static std::atomic_bool WasJoinGame{false};
static std::atomic_bool WasSpectateGame{false};
static std::atomic_bool UpdatePresence{false};
static char JoinGameSecret[256];
static char SpectateGameSecret[256];
static int LastErrorCode{0};
static char LastErrorMessage[256];
static int LastDisconnectErrorCode{0};
static char LastDisconnectErrorMessage[256];
static std::mutex PresenceMutex;
static std::mutex HandlerMutex;
static QueuedMessage QueuedPresence{};
static MsgQueue<QueuedMessage, MessageQueueSize> SendQueue;
static MsgQueue<User, JoinQueueSize> JoinAskQueue;
static User connectedUser;
// We want to auto connect, and retry on failure, but not as fast as possible. This does expoential
// backoff from 0.5 seconds to 1 minute
static Backoff ReconnectTimeMs(500, 60 * 1000);
static auto NextConnect = std::chrono::system_clock::now();
static int Pid{0};
static int Nonce{1};
#ifndef DISCORD_DISABLE_IO_THREAD
static void Discord_UpdateConnection(void);
class IoThreadHolder {
private:
std::atomic_bool keepRunning{true};
std::mutex waitForIOMutex;
std::condition_variable waitForIOActivity;
std::thread ioThread;
public:
void Start()
{
keepRunning.store(true);
ioThread = std::thread([&]() {
const std::chrono::duration<int64_t, std::milli> maxWait{500LL};
Discord_UpdateConnection();
while (keepRunning.load()) {
std::unique_lock<std::mutex> lock(waitForIOMutex);
waitForIOActivity.wait_for(lock, maxWait);
Discord_UpdateConnection();
}
});
}
void Notify() { waitForIOActivity.notify_all(); }
void Stop()
{
keepRunning.exchange(false);
Notify();
if (ioThread.joinable()) {
ioThread.join();
}
}
~IoThreadHolder() { Stop(); }
};
#else
class IoThreadHolder {
public:
void Start() {}
void Stop() {}
void Notify() {}
};
#endif // DISCORD_DISABLE_IO_THREAD
static IoThreadHolder* IoThread{nullptr};
static void UpdateReconnectTime()
{
NextConnect = std::chrono::system_clock::now() +
std::chrono::duration<int64_t, std::milli>{ReconnectTimeMs.nextDelay()};
}
#ifdef DISCORD_DISABLE_IO_THREAD
extern "C" DISCORD_EXPORT void Discord_UpdateConnection(void)
#else
static void Discord_UpdateConnection(void)
#endif
{
if (!Connection) {
return;
}
if (!Connection->IsOpen()) {
if (std::chrono::system_clock::now() >= NextConnect) {
UpdateReconnectTime();
Connection->Open();
}
}
else {
// reads
for (;;) {
JsonDocument message;
if (!Connection->Read(message)) {
break;
}
const char* evtName = GetStrMember(&message, "evt");
const char* nonce = GetStrMember(&message, "nonce");
if (nonce) {
// in responses only -- should use to match up response when needed.
if (evtName && strcmp(evtName, "ERROR") == 0) {
auto data = GetObjMember(&message, "data");
LastErrorCode = GetIntMember(data, "code");
StringCopy(LastErrorMessage, GetStrMember(data, "message", ""));
GotErrorMessage.store(true);
}
}
else {
// should have evt == name of event, optional data
if (evtName == nullptr) {
continue;
}
auto data = GetObjMember(&message, "data");
if (strcmp(evtName, "ACTIVITY_JOIN") == 0) {
auto secret = GetStrMember(data, "secret");
if (secret) {
StringCopy(JoinGameSecret, secret);
WasJoinGame.store(true);
}
}
else if (strcmp(evtName, "ACTIVITY_SPECTATE") == 0) {
auto secret = GetStrMember(data, "secret");
if (secret) {
StringCopy(SpectateGameSecret, secret);
WasSpectateGame.store(true);
}
}
else if (strcmp(evtName, "ACTIVITY_JOIN_REQUEST") == 0) {
auto user = GetObjMember(data, "user");
auto userId = GetStrMember(user, "id");
auto username = GetStrMember(user, "username");
auto avatar = GetStrMember(user, "avatar");
auto joinReq = JoinAskQueue.GetNextAddMessage();
if (userId && username && joinReq) {
StringCopy(joinReq->userId, userId);
StringCopy(joinReq->username, username);
auto discriminator = GetStrMember(user, "discriminator");
if (discriminator) {
StringCopy(joinReq->discriminator, discriminator);
}
if (avatar) {
StringCopy(joinReq->avatar, avatar);
}
else {
joinReq->avatar[0] = 0;
}
JoinAskQueue.CommitAdd();
}
}
}
}
// writes
if (UpdatePresence.exchange(false) && QueuedPresence.length) {
QueuedMessage local;
{
std::lock_guard<std::mutex> guard(PresenceMutex);
local.Copy(QueuedPresence);
}
if (!Connection->Write(local.buffer, local.length)) {
// if we fail to send, requeue
std::lock_guard<std::mutex> guard(PresenceMutex);
QueuedPresence.Copy(local);
UpdatePresence.exchange(true);
}
}
while (SendQueue.HavePendingSends()) {
auto qmessage = SendQueue.GetNextSendMessage();
Connection->Write(qmessage->buffer, qmessage->length);
SendQueue.CommitSend();
}
}
}
static void SignalIOActivity()
{
if (IoThread != nullptr) {
IoThread->Notify();
}
}
static bool RegisterForEvent(const char* evtName)
{
auto qmessage = SendQueue.GetNextAddMessage();
if (qmessage) {
qmessage->length =
JsonWriteSubscribeCommand(qmessage->buffer, sizeof(qmessage->buffer), Nonce++, evtName);
SendQueue.CommitAdd();
SignalIOActivity();
return true;
}
return false;
}
static bool DeregisterForEvent(const char* evtName)
{
auto qmessage = SendQueue.GetNextAddMessage();
if (qmessage) {
qmessage->length =
JsonWriteUnsubscribeCommand(qmessage->buffer, sizeof(qmessage->buffer), Nonce++, evtName);
SendQueue.CommitAdd();
SignalIOActivity();
return true;
}
return false;
}
extern "C" DISCORD_EXPORT void Discord_Initialize(const char* applicationId,
DiscordEventHandlers* handlers,
int autoRegister,
const char* optionalSteamId)
{
IoThread = new (std::nothrow) IoThreadHolder();
if (IoThread == nullptr) {
return;
}
if (autoRegister) {
if (optionalSteamId && optionalSteamId[0]) {
Discord_RegisterSteamGame(applicationId, optionalSteamId);
}
else {
Discord_Register(applicationId, nullptr);
}
}
Pid = GetProcessId();
{
std::lock_guard<std::mutex> guard(HandlerMutex);
if (handlers) {
QueuedHandlers = *handlers;
}
else {
QueuedHandlers = {};
}
Handlers = {};
}
if (Connection) {
return;
}
Connection = RpcConnection::Create(applicationId);
Connection->onConnect = [](JsonDocument& readyMessage) {
Discord_UpdateHandlers(&QueuedHandlers);
if (QueuedPresence.length > 0) {
UpdatePresence.exchange(true);
SignalIOActivity();
}
auto data = GetObjMember(&readyMessage, "data");
auto user = GetObjMember(data, "user");
auto userId = GetStrMember(user, "id");
auto username = GetStrMember(user, "username");
auto avatar = GetStrMember(user, "avatar");
if (userId && username) {
StringCopy(connectedUser.userId, userId);
StringCopy(connectedUser.username, username);
auto discriminator = GetStrMember(user, "discriminator");
if (discriminator) {
StringCopy(connectedUser.discriminator, discriminator);
}
if (avatar) {
StringCopy(connectedUser.avatar, avatar);
}
else {
connectedUser.avatar[0] = 0;
}
}
WasJustConnected.exchange(true);
ReconnectTimeMs.reset();
};
Connection->onDisconnect = [](int err, const char* message) {
LastDisconnectErrorCode = err;
StringCopy(LastDisconnectErrorMessage, message);
WasJustDisconnected.exchange(true);
UpdateReconnectTime();
};
IoThread->Start();
}
extern "C" DISCORD_EXPORT void Discord_Shutdown(void)
{
if (!Connection) {
return;
}
Connection->onConnect = nullptr;
Connection->onDisconnect = nullptr;
Handlers = {};
QueuedPresence.length = 0;
UpdatePresence.exchange(false);
if (IoThread != nullptr) {
IoThread->Stop();
delete IoThread;
IoThread = nullptr;
}
RpcConnection::Destroy(Connection);
}
extern "C" DISCORD_EXPORT void Discord_UpdatePresence(const DiscordRichPresence* presence)
{
{
std::lock_guard<std::mutex> guard(PresenceMutex);
QueuedPresence.length = JsonWriteRichPresenceObj(
QueuedPresence.buffer, sizeof(QueuedPresence.buffer), Nonce++, Pid, presence);
UpdatePresence.exchange(true);
}
SignalIOActivity();
}
extern "C" DISCORD_EXPORT void Discord_ClearPresence(void)
{
Discord_UpdatePresence(nullptr);
}
extern "C" DISCORD_EXPORT void Discord_Respond(const char* userId, /* DISCORD_REPLY_ */ int reply)
{
// if we are not connected, let's not batch up stale messages for later
if (!Connection || !Connection->IsOpen()) {
return;
}
auto qmessage = SendQueue.GetNextAddMessage();
if (qmessage) {
qmessage->length =
JsonWriteJoinReply(qmessage->buffer, sizeof(qmessage->buffer), userId, reply, Nonce++);
SendQueue.CommitAdd();
SignalIOActivity();
}
}
extern "C" DISCORD_EXPORT void Discord_RunCallbacks(void)
{
// Note on some weirdness: internally we might connect, get other signals, disconnect any number
// of times inbetween calls here. Externally, we want the sequence to seem sane, so any other
// signals are book-ended by calls to ready and disconnect.
if (!Connection) {
return;
}
bool wasDisconnected = WasJustDisconnected.exchange(false);
bool isConnected = Connection->IsOpen();
if (isConnected) {
// if we are connected, disconnect cb first
std::lock_guard<std::mutex> guard(HandlerMutex);
if (wasDisconnected && Handlers.disconnected) {
Handlers.disconnected(LastDisconnectErrorCode, LastDisconnectErrorMessage);
}
}
if (WasJustConnected.exchange(false)) {
std::lock_guard<std::mutex> guard(HandlerMutex);
if (Handlers.ready) {
DiscordUser du{connectedUser.userId,
connectedUser.username,
connectedUser.discriminator,
connectedUser.avatar};
Handlers.ready(&du);
}
}
if (GotErrorMessage.exchange(false)) {
std::lock_guard<std::mutex> guard(HandlerMutex);
if (Handlers.errored) {
Handlers.errored(LastErrorCode, LastErrorMessage);
}
}
if (WasJoinGame.exchange(false)) {
std::lock_guard<std::mutex> guard(HandlerMutex);
if (Handlers.joinGame) {
Handlers.joinGame(JoinGameSecret);
}
}
if (WasSpectateGame.exchange(false)) {
std::lock_guard<std::mutex> guard(HandlerMutex);
if (Handlers.spectateGame) {
Handlers.spectateGame(SpectateGameSecret);
}
}
// Right now this batches up any requests and sends them all in a burst; I could imagine a world
// where the implementer would rather sequentially accept/reject each one before the next invite
// is sent. I left it this way because I could also imagine wanting to process these all and
// maybe show them in one common dialog and/or start fetching the avatars in parallel, and if
// not it should be trivial for the implementer to make a queue themselves.
while (JoinAskQueue.HavePendingSends()) {
auto req = JoinAskQueue.GetNextSendMessage();
{
std::lock_guard<std::mutex> guard(HandlerMutex);
if (Handlers.joinRequest) {
DiscordUser du{req->userId, req->username, req->discriminator, req->avatar};
Handlers.joinRequest(&du);
}
}
JoinAskQueue.CommitSend();
}
if (!isConnected) {
// if we are not connected, disconnect message last
std::lock_guard<std::mutex> guard(HandlerMutex);
if (wasDisconnected && Handlers.disconnected) {
Handlers.disconnected(LastDisconnectErrorCode, LastDisconnectErrorMessage);
}
}
}
extern "C" DISCORD_EXPORT void Discord_UpdateHandlers(DiscordEventHandlers* newHandlers)
{
if (newHandlers) {
#define HANDLE_EVENT_REGISTRATION(handler_name, event) \
if (!Handlers.handler_name && newHandlers->handler_name) { \
RegisterForEvent(event); \
} \
else if (Handlers.handler_name && !newHandlers->handler_name) { \
DeregisterForEvent(event); \
}
std::lock_guard<std::mutex> guard(HandlerMutex);
HANDLE_EVENT_REGISTRATION(joinGame, "ACTIVITY_JOIN")
HANDLE_EVENT_REGISTRATION(spectateGame, "ACTIVITY_SPECTATE")
HANDLE_EVENT_REGISTRATION(joinRequest, "ACTIVITY_JOIN_REQUEST")
#undef HANDLE_EVENT_REGISTRATION
Handlers = *newHandlers;
}
else {
std::lock_guard<std::mutex> guard(HandlerMutex);
Handlers = {};
}
return;
}