Add Set::exclude_from_history on linux by setting x-kde-passwordManagerHint

src/common.rs

@@ -176,7 +176,7 @@ impl<F: FnOnce()> Drop for ScopeGuard<F> {
 pub(crate) mod private {
 	// This is currently unused on macOS, so silence the warning which appears
 	// since there's no extension traits making use of this trait sealing structure.
-	#[cfg_attr(target_vendor = "apple", allow(unreachable_pub))]
+	#[cfg_attr(target_vendor = "apple", allow(unreachable_pub, dead_code))]
 	pub trait Sealed {}
 
 	impl Sealed for crate::Get<'_> {}

src/platform/linux/mod.rs

@@ -7,6 +7,10 @@ use log::{trace, warn};
 use crate::ImageData;
 use crate::{common::private, Error};
 
+// Magic strings used in `Set::exclude_from_history()` on linux
+const KDE_EXCLUSION_MIME: &str = "x-kde-passwordManagerHint";
+const KDE_EXCLUSION_HINT: &[u8] = b"secret";
+
 mod x11;
 
 #[cfg(feature = "wayland-data-control")]
@@ -158,19 +162,29 @@ pub(crate) struct Set<'clipboard> {
 	clipboard: &'clipboard mut Clipboard,
 	wait: WaitConfig,
 	selection: LinuxClipboardKind,
+	exclude_from_history: bool,
 }
 
 impl<'clipboard> Set<'clipboard> {
 	pub(crate) fn new(clipboard: &'clipboard mut Clipboard) -> Self {
-		Self { clipboard, wait: WaitConfig::default(), selection: LinuxClipboardKind::Clipboard }
+		Self {
+			clipboard,
+			wait: WaitConfig::default(),
+			selection: LinuxClipboardKind::Clipboard,
+			exclude_from_history: false,
+		}
 	}
 
 	pub(crate) fn text(self, text: Cow<'_, str>) -> Result<(), Error> {
 		match self.clipboard {
-			Clipboard::X11(clipboard) => clipboard.set_text(text, self.selection, self.wait),
+			Clipboard::X11(clipboard) => {
+				clipboard.set_text(text, self.selection, self.wait, self.exclude_from_history)
+			}
 
 			#[cfg(feature = "wayland-data-control")]
-			Clipboard::WlDataControl(clipboard) => clipboard.set_text(text, self.selection, self.wait),
+			Clipboard::WlDataControl(clipboard) => {
+				clipboard.set_text(text, self.selection, self.wait, self.exclude_from_history)
+			}
 		}
 	}
 
@@ -254,6 +268,13 @@ pub trait SetExtLinux: private::Sealed {
 	/// # }
 	/// ```
 	fn clipboard(self, selection: LinuxClipboardKind) -> Self;
+
+	/// Excludes the data which will be set on the clipboard from being added to
+	/// the desktop clipboard managers' histories by adding the MIME-Type `x-kde-passwordMangagerHint`
+	/// to the clipboard's selection data.
+	///
+	/// This is the most widely adopted convention on Linux.
+	fn exclude_from_history(self) -> Self;
 }
 
 impl SetExtLinux for crate::Set<'_> {
@@ -271,6 +292,11 @@ impl SetExtLinux for crate::Set<'_> {
 		self.platform.wait = WaitConfig::Until(deadline);
 		self
 	}
+
+	fn exclude_from_history(mut self) -> Self {
+		self.platform.exclude_from_history = true;
+		self
+	}
 }
 
 pub(crate) struct Clear<'clipboard> {

src/platform/linux/wayland.rs

@@ -10,6 +10,7 @@ use wl_clipboard_rs::{
 #[cfg(feature = "image-data")]
 use super::encode_as_png;
 use super::{into_unknown, LinuxClipboardKind, WaitConfig};
+use super::{KDE_EXCLUSION_HINT, KDE_EXCLUSION_MIME};
 use crate::common::Error;
 #[cfg(feature = "image-data")]
 use crate::common::ImageData;
@@ -79,12 +80,24 @@ impl Clipboard {
 		text: Cow<'_, str>,
 		selection: LinuxClipboardKind,
 		wait: WaitConfig,
+		exclude_from_history: bool,
 	) -> Result<(), Error> {
 		let mut opts = Options::new();
 		opts.foreground(matches!(wait, WaitConfig::Forever));
 		opts.clipboard(selection.try_into()?);
 		let source = Source::Bytes(text.into_owned().into_bytes().into_boxed_slice());
-		opts.copy(source, MimeType::Text).map_err(|e| match e {
+		if exclude_from_history {
+			opts.copy_multi(vec![
+				MimeSource { source, mime_type: MimeType::Text },
+				MimeSource {
+					source: Source::Bytes(Box::from(KDE_EXCLUSION_HINT)),
+					mime_type: MimeType::Specific(String::from(KDE_EXCLUSION_MIME)),
+				},
+			])
+		} else {
+			opts.copy(source, MimeType::Text)
+		}
+		.map_err(|e| match e {
 			CopyError::PrimarySelectionUnsupported => Error::ClipboardNotSupported,
 			other => into_unknown(other),
 		})?;

src/platform/linux/x11.rs

@@ -23,7 +23,6 @@ use std::{
 	thread::JoinHandle,
 	thread_local,
 	time::{Duration, Instant},
-	usize,
 };
 
 use log::{error, trace, warn};
@@ -46,6 +45,7 @@ use x11rb::{
 #[cfg(feature = "image-data")]
 use super::encode_as_png;
 use super::{into_unknown, LinuxClipboardKind, WaitConfig};
+use super::{KDE_EXCLUSION_HINT, KDE_EXCLUSION_MIME};
 #[cfg(feature = "image-data")]
 use crate::ImageData;
 use crate::{common::ScopeGuard, Error};
@@ -80,6 +80,7 @@ x11rb::atom_manager! {
 		HTML: b"text/html",
 
 		PNG_MIME: b"image/png",
+		X_KDE_PASSWORDMANAGERHINT: KDE_EXCLUSION_MIME.as_bytes(),
 
 		// This is just some random name for the property on our window, into which
 		// the clipboard owner writes the data we requested.
@@ -878,11 +879,19 @@ impl Clipboard {
 		message: Cow<'_, str>,
 		selection: LinuxClipboardKind,
 		wait: WaitConfig,
+		exclude_from_history: bool,
 	) -> Result<()> {
-		let data = vec![ClipboardData {
+		let mut data = vec![];
+		data.push(ClipboardData {
 			bytes: message.into_owned().into_bytes(),
 			format: self.inner.atoms.UTF8_STRING,
-		}];
+		});
+		if exclude_from_history {
+			data.push(ClipboardData {
+				bytes: KDE_EXCLUSION_HINT.to_vec(),
+				format: self.inner.atoms.X_KDE_PASSWORDMANAGERHINT,
+			});
+		}
 		self.inner.write(data, selection, wait)
 	}