* Generalize message box hook function

src/windows/MessageList.cpp

@@ -1777,54 +1777,19 @@ void MessageList::DetermineMessageData(
 	}
 }
 
-static HHOOK g_MsgBoxHookTemp = NULL;
-
-LRESULT MessageList::OpenLinkMsgBoxHook(int code, WPARAM wParam, LPARAM lParam)
-{
-	if (code == HC_ACTION)
-	{
-		CWPRETSTRUCT* cwp = (CWPRETSTRUCT*)lParam;
-
-		if (cwp->message == WM_INITDIALOG) {
-			HWND hWnd = cwp->hwnd;
-
-			HWND item = GetDlgItem(hWnd, IDOK);
-			if (item)
-				SetWindowText(item, TmGetTString(IDS_EXCITED_YES));
-		}
-
-		LRESULT res = CallNextHookEx(g_MsgBoxHookTemp, code, wParam, lParam);
-
-		if (cwp->message == WM_NCDESTROY) {
-			UnhookWindowsHookEx(g_MsgBoxHookTemp);
-			g_MsgBoxHookTemp = NULL;
-		}
-
-		return res;
-	}
-
-	return CallNextHookEx(g_MsgBoxHookTemp, code, wParam, lParam);
-}
-
 void MessageList::ConfirmOpenLink(const std::string& link)
 {
 	bool trust = GetLocalSettings()->CheckTrustedDomain(link);
 
 	if (!trust)
 	{
-		if (g_MsgBoxHookTemp) {
-			UnhookWindowsHookEx(g_MsgBoxHookTemp);
-			g_MsgBoxHookTemp = NULL;
-		}
-
-		g_MsgBoxHookTemp = SetWindowsHookEx(WH_CALLWNDPROCRET, MessageList::OpenLinkMsgBoxHook, NULL, GetCurrentThreadId());
-
-		TCHAR buffer[8192];
+		static TCHAR buffer[8192];
 		LPTSTR tstr = ConvertCppStringToTString(link);
 		WAsnprintf(buffer, _countof(buffer), TmGetTString(IDS_LINK_CONFIRM), tstr);
+		buffer[_countof(buffer) - 1] = 0;
 		free(tstr);
 
-		if (MessageBox(g_Hwnd, buffer, TmGetTString(IDS_HOLD_UP_CONFIRM), MB_ICONWARNING | MB_OKCANCEL) != IDOK)
+		if (MessageBoxHooked(g_Hwnd, buffer, TmGetTString(IDS_HOLD_UP_CONFIRM), MB_ICONWARNING | MB_OKCANCEL, IDOK, TmGetTString(IDS_EXCITED_YES)) != IDOK)
 			return;
 	}
 

src/windows/MessageList.hpp

@@ -536,8 +536,6 @@ class MessageList
 
 	static COLORREF DrawMentionBackground(HDC hdc, RECT& rc, COLORREF chosenBkColor);
 
-	static LRESULT CALLBACK OpenLinkMsgBoxHook(int code, WPARAM wParam, LPARAM lParam);
-
 	// called by OnUpdateEmoji
 	static void InvalidateEmote(void* context, const Rect& rc);
 };

src/windows/WinUtils.cpp

@@ -1029,3 +1029,73 @@ void CenterWindow(HWND hWnd, HWND hRelativeTo)
 
 	MoveWindow(hWnd, rect1.left, rect1.top, rect1.right - rect1.left, rect1.bottom - rect1.top, TRUE);
 }
+
+#ifndef MINGW_SPECIFIC_HACKS
+#include <mutex>
+using Wmutex = std::mutex;
+#else
+#include <iprog/mutex.hpp>
+using Wmutex = iprog::mutex;
+#endif
+
+static const LPCTSTR* s_msgBoxText;
+static const int*     s_msgBoxIDReplaced;
+
+static Wmutex s_msgBoxMutex;
+static int    s_msgBoxCount;
+static HHOOK  s_msgBoxHook;
+
+LRESULT CALLBACK MessageBoxHookFunc(int code, WPARAM wParam, LPARAM lParam)
+{
+	if (code == HC_ACTION)
+	{
+		CWPRETSTRUCT* cwp = (CWPRETSTRUCT*)lParam;
+
+		if (cwp->message == WM_INITDIALOG) {
+			HWND hWnd = cwp->hwnd;
+
+			for (int i = 0; i < s_msgBoxCount; i++) {
+				SetDlgItemText(hWnd, s_msgBoxIDReplaced[i], s_msgBoxText[i]);
+			}
+			s_msgBoxCount = 0;
+		}
+
+		LRESULT res = CallNextHookEx(s_msgBoxHook, code, wParam, lParam);
+
+		if (cwp->message == WM_INITDIALOG) {
+			// just unhook the hook, we don't care about overriding any other behavior
+			UnhookWindowsHookEx(s_msgBoxHook);
+			s_msgBoxHook = NULL;
+
+			// mutex was locked before the MessageBox call!
+#pragma warning(push)
+#pragma warning(disable : 26110)
+			s_msgBoxMutex.unlock();
+#pragma warning(pop)
+		}
+
+		return res;
+	}
+
+	return CallNextHookEx(s_msgBoxHook, code, wParam, lParam);
+}
+
+// This calls MessageBox() with the important difference that one of the buttons (specified by overID)
+// will have its text changed via a hook.
+int MessageBoxHooked(HWND hWnd, LPCTSTR title, LPCTSTR caption, int flags, int overCount, const int* overID, const LPCTSTR* overText)
+{
+	s_msgBoxMutex.lock(); // will be unlocked in MessageBox's hook
+
+	s_msgBoxCount = overCount;
+	s_msgBoxText = overText;
+	s_msgBoxIDReplaced = overID;
+
+	s_msgBoxHook = SetWindowsHookEx(WH_CALLWNDPROCRET, MessageBoxHookFunc, NULL, GetCurrentThreadId());
+
+	return MessageBox(hWnd, title, caption, flags);
+}
+
+int MessageBoxHooked(HWND hWnd, LPCTSTR title, LPCTSTR caption, int flags, int overID, LPCTSTR overText)
+{
+	return MessageBoxHooked(hWnd, title, caption, flags, 1, &overID, &overText);
+}

src/windows/WinUtils.hpp

@@ -78,6 +78,8 @@ void DrawErrorBox(HDC hdc, RECT rect);
 bool GetDataFromBitmap(HDC hdc, HBITMAP hbm, BYTE*& pBytes, int& width, int& height, int& bpp);
 int HandleGestureMessage(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, float mulDeltas = 1.0f);
 std::string CutOutURLPath(const std::string& url);
+int MessageBoxHooked(HWND hWnd, LPCTSTR title, LPCTSTR caption, int flags, int overID, LPCTSTR overText);
+int MessageBoxHooked(HWND hWnd, LPCTSTR title, LPCTSTR caption, int flags, int overCount, const int* overID, const LPCTSTR*  overText);
 
 #ifdef USE_DEBUG_PRINTS
 void DbgPrintW(const char* fmt, ...);