From 44028cbbb144e97315f8653323b81efbe0947934 Mon Sep 17 00:00:00 2001
From: Sepalani <sepalani@hotmail.fr>
Date: Thu, 6 Jun 2024 21:40:05 +0400
Subject: [PATCH] Socket: Fix connect issues when using ReShade

---
 Source/Core/Common/SocketContext.cpp    | 21 ++++++++++++++++++++-
 Source/Core/Core/IOS/Network/Socket.cpp | 13 ++++++++++++-
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/Source/Core/Common/SocketContext.cpp b/Source/Core/Common/SocketContext.cpp
index 15f9fd9010..f9c630c434 100644
--- a/Source/Core/Common/SocketContext.cpp
+++ b/Source/Core/Common/SocketContext.cpp
@@ -3,6 +3,9 @@
 
 #include "Common/SocketContext.h"
 
+#include "Common/Logging/Log.h"
+#include "Common/Network.h"
+
 namespace Common
 {
 #ifdef _WIN32
@@ -11,7 +14,23 @@ SocketContext::SocketContext()
   std::lock_guard<std::mutex> g(s_lock);
   if (s_num_objects == 0)
   {
-    static_cast<void>(WSAStartup(MAKEWORD(2, 2), &s_data));
+    const int ret = WSAStartup(MAKEWORD(2, 2), &s_data);
+    if (ret == 0)
+    {
+      INFO_LOG_FMT(COMMON, "WSAStartup succeeded, wVersion={}.{}, wHighVersion={}.{}",
+                   int(LOBYTE(s_data.wVersion)), int(HIBYTE(s_data.wVersion)),
+                   int(LOBYTE(s_data.wHighVersion)), int(HIBYTE(s_data.wHighVersion)));
+    }
+    else
+    {
+      // The WSAStartup function directly returns the extended error code in the return value.
+      // A call to the WSAGetLastError function is not needed and should not be used.
+      //
+      // Source:
+      // https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-wsastartup
+      ERROR_LOG_FMT(COMMON, "WSAStartup failed with error {}: {}", ret,
+                    Common::DecodeNetworkError(ret));
+    }
   }
   s_num_objects++;
 }
diff --git a/Source/Core/Core/IOS/Network/Socket.cpp b/Source/Core/Core/IOS/Network/Socket.cpp
index 4b7c2e2c8a..59f8e31814 100644
--- a/Source/Core/Core/IOS/Network/Socket.cpp
+++ b/Source/Core/Core/IOS/Network/Socket.cpp
@@ -97,6 +97,17 @@ s32 WiiSockMan::GetNetErrorCode(s32 ret, std::string_view caller, bool is_rw)
 {
 #ifdef _WIN32
   s32 error_code = WSAGetLastError();
+  // Some programs might hijack WinSock2 (e.g. ReShade) and alter the expected return value.
+  if (error_code == WSAEINVAL && caller == "SO_CONNECT")
+  {
+    // Note:
+    // In order to preserve backward compatibility, this error is reported as WSAEINVAL to Windows
+    // Sockets 1.1 applications that link to either Winsock.dll or Wsock32.dll.
+    //
+    // Source:
+    // https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-connect
+    error_code = WSAEALREADY;
+  }
 #else
   s32 error_code = errno;
 #endif
@@ -292,7 +303,7 @@ void WiiSocket::Update(bool read, bool write, bool except)
         memory.CopyFromEmu(&addr, ioctl.buffer_in + 8, sizeof(WiiSockAddrIn));
         sockaddr_in local_name = WiiSockMan::ToNativeAddrIn(addr);
 
-        int ret = connect(fd, (sockaddr*)&local_name, sizeof(local_name));
+        const int ret = connect(fd, (sockaddr*)&local_name, sizeof(local_name));
         ReturnValue = m_socket_manager.GetNetErrorCode(ret, "SO_CONNECT", false);
         UpdateConnectingState(ReturnValue);