1 files changed, 137 insertions, 0 deletions
diff --git a/externals/discord-rpc/src/rpc_connection.cpp b/externals/discord-rpc/src/rpc_connection.cpp
new file mode 100644
index 0000000000..0933162169
--- /dev/null
+++ b/externals/discord-rpc/src/rpc_connection.cpp
@@ -0,0 +1,137 @@
+#include "rpc_connection.h"
+#include "serialization.h"
+
+#include <atomic>
+
+static const int RpcVersion = 1;
+static RpcConnection Instance;
+
+/*static*/ RpcConnection* RpcConnection::Create(const char* applicationId)
+{
+    Instance.connection = BaseConnection::Create();
+    StringCopy(Instance.appId, applicationId);
+    return &Instance;
+}
+
+/*static*/ void RpcConnection::Destroy(RpcConnection*& c)
+{
+    c->Close();
+    BaseConnection::Destroy(c->connection);
+    c = nullptr;
+}
+
+void RpcConnection::Open()
+{
+    if (state == State::Connected) {
+        return;
+    }
+
+    if (state == State::Disconnected && !connection->Open()) {
+        return;
+    }
+
+    if (state == State::SentHandshake) {
+        JsonDocument message;
+        if (Read(message)) {
+            auto cmd = GetStrMember(&message, "cmd");
+            auto evt = GetStrMember(&message, "evt");
+            if (cmd && evt && !strcmp(cmd, "DISPATCH") && !strcmp(evt, "READY")) {
+                state = State::Connected;
+                if (onConnect) {
+                    onConnect(message);
+                }
+            }
+        }
+    }
+    else {
+        sendFrame.opcode = Opcode::Handshake;
+        sendFrame.length = (uint32_t)JsonWriteHandshakeObj(
+          sendFrame.message, sizeof(sendFrame.message), RpcVersion, appId);
+
+        if (connection->Write(&sendFrame, sizeof(MessageFrameHeader) + sendFrame.length)) {
+            state = State::SentHandshake;
+        }
+        else {
+            Close();
+        }
+    }
+}
+
+void RpcConnection::Close()
+{
+    if (onDisconnect && (state == State::Connected || state == State::SentHandshake)) {
+        onDisconnect(lastErrorCode, lastErrorMessage);
+    }
+    connection->Close();
+    state = State::Disconnected;
+}
+
+bool RpcConnection::Write(const void* data, size_t length)
+{
+    sendFrame.opcode = Opcode::Frame;
+    memcpy(sendFrame.message, data, length);
+    sendFrame.length = (uint32_t)length;
+    if (!connection->Write(&sendFrame, sizeof(MessageFrameHeader) + length)) {
+        Close();
+        return false;
+    }
+    return true;
+}
+
+bool RpcConnection::Read(JsonDocument& message)
+{
+    if (state != State::Connected && state != State::SentHandshake) {
+        return false;
+    }
+    MessageFrame readFrame;
+    for (;;) {
+        bool didRead = connection->Read(&readFrame, sizeof(MessageFrameHeader));
+        if (!didRead) {
+            if (!connection->isOpen) {
+                lastErrorCode = (int)ErrorCode::PipeClosed;
+                StringCopy(lastErrorMessage, "Pipe closed");
+                Close();
+            }
+            return false;
+        }
+
+        if (readFrame.length > 0) {
+            didRead = connection->Read(readFrame.message, readFrame.length);
+            if (!didRead) {
+                lastErrorCode = (int)ErrorCode::ReadCorrupt;
+                StringCopy(lastErrorMessage, "Partial data in frame");
+                Close();
+                return false;
+            }
+            readFrame.message[readFrame.length] = 0;
+        }
+
+        switch (readFrame.opcode) {
+        case Opcode::Close: {
+            message.ParseInsitu(readFrame.message);
+            lastErrorCode = GetIntMember(&message, "code");
+            StringCopy(lastErrorMessage, GetStrMember(&message, "message", ""));
+            Close();
+            return false;
+        }
+        case Opcode::Frame:
+            message.ParseInsitu(readFrame.message);
+            return true;
+        case Opcode::Ping:
+            readFrame.opcode = Opcode::Pong;
+            if (!connection->Write(&readFrame, sizeof(MessageFrameHeader) + readFrame.length)) {
+                Close();
+            }
+            break;
+        case Opcode::Pong:
+            break;
+        case Opcode::Handshake:
+        default:
+            // something bad happened
+            lastErrorCode = (int)ErrorCode::ReadCorrupt;
+            StringCopy(lastErrorMessage, "Bad ipc frame");
+            Close();
+            return false;
+        }
+    }
+}