From da21ac3792e5a49636df8ef69c00f2392932a21b Mon Sep 17 00:00:00 2001
From: akallabeth <akallabeth@posteo.net>
Date: Thu, 10 Apr 2025 13:24:51 +0200
Subject: [PATCH] [client,sdl] fix clipboard updates

* Ignore updates for our own data (use a special clipboard format to
  identify these)
---
 client/SDL/SDL3/sdl_clip.cpp | 31 +++++++++++++++++++++++++++----
 client/SDL/SDL3/sdl_clip.hpp |  1 +
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/client/SDL/SDL3/sdl_clip.cpp b/client/SDL/SDL3/sdl_clip.cpp
index db4f2b0c8..e77a65aa9 100644
--- a/client/SDL/SDL3/sdl_clip.cpp
+++ b/client/SDL/SDL3/sdl_clip.cpp
@@ -90,6 +90,8 @@ static const std::vector<const char*>& s_mime_image()
 static const char s_mime_gnome_copied_files[] = "x-special/gnome-copied-files";
 static const char s_mime_mate_copied_files[] = "x-special/mate-copied-files";
 
+static const char s_mime_freerdp_update[] = "x-special/freerdp-clipboard-update";
+
 static const char* s_type_HtmlFormat = "HTML Format";
 static const char* s_type_FileGroupDescriptorW = "FileGroupDescriptorW";
 
@@ -164,12 +166,23 @@ BOOL sdlClip::uninit(CliprdrClientContext* clip)
 	return TRUE;
 }
 
+static bool contains(const char** mime_types, Sint32 count)
+{
+	for (Sint32 x = 0; x < count; x++)
+	{
+		const auto mime = mime_types[x];
+		if (mime && (strcmp(s_mime_freerdp_update, mime) == 0))
+			return true;
+	}
+	return false;
+}
+
 bool sdlClip::handle_update(const SDL_ClipboardEvent& ev)
 {
 	if (!_ctx || !_sync || ev.owner)
 	{
-		/* TODO: Hack to identify our own updates */
-		if (ev.owner && (ev.reserved == 0x42))
+		_last_timestamp = ev.timestamp;
+		if (!_current_mimetypes.empty())
 		{
 			_cache_data.clear();
 			auto rc =
@@ -181,6 +194,16 @@ bool sdlClip::handle_update(const SDL_ClipboardEvent& ev)
 		return true;
 	}
 
+	if (ev.timestamp == _last_timestamp)
+	{
+		return true;
+	}
+
+	if (contains(ev.mime_types, ev.num_mime_types))
+	{
+		return true;
+	}
+
 	clearServerFormats();
 
 	std::string mime_html = s_mime_html;
@@ -519,15 +542,15 @@ UINT sdlClip::ReceiveServerFormatList(CliprdrClientContext* context,
 		clipboard->_current_mimetypes.push_back(s_mime_gnome_copied_files);
 		clipboard->_current_mimetypes.push_back(s_mime_mate_copied_files);
 	}
+	clipboard->_current_mimetypes.push_back(s_mime_freerdp_update);
 
 	auto s = clipboard->_current_mimetypes.size();
 	SDL_Event ev = { SDL_EVENT_CLIPBOARD_UPDATE };
 	ev.clipboard.owner = true;
+	ev.clipboard.timestamp = SDL_GetTicksNS();
 	ev.clipboard.num_mime_types = WINPR_ASSERTING_INT_CAST(Sint32, s);
 	ev.clipboard.mime_types = clipboard->_current_mimetypes.data();
 
-	/* TODO: Hack to identify our own updates */
-	ev.clipboard.reserved = 0x42;
 	auto rc = (SDL_PushEvent(&ev) == 1);
 	return clipboard->SendFormatListResponse(rc);
 }
diff --git a/client/SDL/SDL3/sdl_clip.hpp b/client/SDL/SDL3/sdl_clip.hpp
index 1119c840b..5df648cde 100644
--- a/client/SDL/SDL3/sdl_clip.hpp
+++ b/client/SDL/SDL3/sdl_clip.hpp
@@ -144,6 +144,7 @@ class sdlClip
 	wClipboard* _system = nullptr;
 	std::atomic<bool> _sync = false;
 	HANDLE _event;
+	Uint64 _last_timestamp = 0;
 
 	std::vector<CliprdrFormat> _serverFormats;
 	CriticalSection _lock;