Release 0.4.11: three small fixes closing out the backlog

- **#40 Skip VDD reinstall on upgrade**: install_vdd() is now
  idempotent (no-op if MttVDD device node already registered), and
  uninstall_service no longer auto-removes VDD. The old behaviour
  shunted user windows off-screen on every phantom-server upgrade
  because Windows migrated VDD-hosted windows to the physical display
  during the few seconds VDD was absent. For a full wipe operators
  now call the new --uninstall-vdd flag explicitly (symmetric to the
  existing --install-vdd from 0.4.3).

- **#41 Error-swallowing cleanup in session.rs**: input-inject +
  IPC-forward failures now log via tracing::warn! instead of being
  silently dropped. In Windows Service mode a broken IPC pipe
  previously silently lost every keystroke with no signal.
  spawn_receive_thread also now breaks its read loop when the session
  receiver is gone, instead of reading + discarding from the network
  until the peer happens to close.

- **#42 --decoder flag strict validation**: clap now rejects values
  outside {auto, openh264, videotoolbox, dav1d, nvdec} instead of
  silently falling through to OpenH264. Help text updated to explain
  that on non-macOS `dav1d` / `nvdec` currently still follow the auto-
  probe chain rather than acting as forced selectors — honest docs
  over silent misdirection.

Also closed task #25 as decided (stay with MTT VDD) and moved
#34 (AV1 codec negotiation) to deferred — the blocker is upstream
AV1 decode maturity, not the protocol work.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: huaying

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "phantom-bench"
-version = "0.4.10"
+version = "0.4.11"
 edition = "2021"
 
 [dependencies]

crates/bench/Cargo.toml

@@ -161,10 +161,7 @@ impl OpenH264Bench {
 
 fn component_bench(cuda: Option<&Arc<CudaLib>>, av1_supported: bool) {
     println!("=== Component bench (encoder only, {ROUNDS} rounds + {WARMUP} warmup) ===\n");
-    println!(
-        "{:<8} {:>8} {:<10} Result",
-        "Res", "Bitrate", "Encoder"
-    );
+    println!("{:<8} {:>8} {:<10} Result", "Res", "Bitrate", "Encoder");
     println!("{}", "-".repeat(80));
 
     for &(w, h, label) in RESOLUTIONS {

crates/bench/src/main.rs

@@ -1,6 +1,6 @@
 [package]
 name = "phantom-client"
-version = "0.4.10"
+version = "0.4.11"
 edition = "2021"
 
 [dependencies]

crates/client/Cargo.toml

@@ -54,8 +54,20 @@ struct Args {
     no_encrypt: bool,
     #[arg(long, default_value = "tcp")]
     transport: String,
-    /// Video decoder: auto (default), openh264 (CPU), videotoolbox (macOS GPU).
-    #[arg(long, default_value = "auto")]
+    /// Video decoder hint. Accepted values: auto (default), openh264,
+    /// videotoolbox, dav1d, nvdec.
+    ///
+    /// The hint is honoured fully on macOS (auto / videotoolbox take the
+    /// hardware path; anything else forces OpenH264). On Linux / Windows
+    /// `auto` auto-probes NVDEC → dav1d (AV1 only) → OpenH264, and
+    /// `dav1d` / `nvdec` currently fall through the same probe chain —
+    /// they aren't forced selectors. Passing a value outside the list
+    /// errors here instead of silently falling through like older builds.
+    #[arg(
+        long,
+        default_value = "auto",
+        value_parser = ["auto", "openh264", "videotoolbox", "dav1d", "nvdec"]
+    )]
     decoder: String,
     /// Send a file to the server after connecting.
     #[arg(long)]

crates/client/src/main.rs

@@ -1,6 +1,6 @@
 [package]
 name = "phantom-core"
-version = "0.4.10"
+version = "0.4.11"
 edition = "2021"
 
 [features]

crates/core/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "phantom-gpu"
-version = "0.4.10"
+version = "0.4.11"
 edition = "2021"
 
 [features]

crates/gpu/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "phantom-server"
-version = "0.4.10"
+version = "0.4.11"
 edition = "2021"
 
 [features]

crates/server/Cargo.toml

@@ -103,6 +103,15 @@ struct Args {
     #[arg(long)]
     install_vdd: bool,
 
+    /// (Windows only) Remove only the Virtual Display Driver and leave the
+    /// phantom-server service alone. Use this when you actually want VDD
+    /// gone — `--uninstall` no longer touches VDD by default because
+    /// removing + reinstalling it on every upgrade was shunting user
+    /// windows off-screen.
+    #[cfg(target_os = "windows")]
+    #[arg(long)]
+    uninstall_vdd: bool,
+
     /// Send a file to the first client that connects.
     #[arg(long)]
     send_file: Option<String>,
@@ -327,6 +336,15 @@ fn main() -> Result<()> {
         );
         return service_win::install_vdd(&install_dir);
     }
+    #[cfg(target_os = "windows")]
+    if args.uninstall_vdd {
+        let install_dir = std::path::PathBuf::from(r"C:\Program Files\Phantom");
+        println!(
+            "Removing Virtual Display Driver at {}",
+            install_dir.display()
+        );
+        return service_win::uninstall_vdd(&install_dir);
+    }
 
     let frame_interval = Duration::from_secs_f64(1.0 / args.fps as f64);
 

crates/server/src/main.rs

@@ -1174,9 +1174,42 @@ fn ps_unzip(zip: &std::path::Path, dest: &std::path::Path) -> anyhow::Result<()>
 
 /// Install the Virtual Display Driver for headless GPU servers.
 /// Downloads VDD + nefcon from GitHub, installs driver via nefconw.
+/// Ask pnputil whether any MttVDD device node is currently registered.
+/// Used by `install_vdd` to skip the reinstall on upgrade and by
+/// callers that want to check state without doing any install work.
+pub fn vdd_device_present() -> bool {
+    let out = std::process::Command::new("pnputil")
+        .args(["/enum-devices", "/connected"])
+        .output();
+    match out {
+        Ok(o) => {
+            let s = String::from_utf8_lossy(&o.stdout);
+            // MttVDD's hardware id is `Root\MttVDD`. Match case-insensitive
+            // on "MttVDD" to cover localized pnputil output.
+            s.to_lowercase().contains("mttvdd")
+        }
+        Err(_) => false,
+    }
+}
+
 pub fn install_vdd(install_dir: &std::path::Path) -> anyhow::Result<()> {
     use anyhow::Context;
 
+    // Idempotent: if the MttVDD device node is already present, skip the
+    // whole download + nefcon dance. This is the upgrade path — phantom-
+    // server `--uninstall` + `--install` was previously causing VDD to
+    // disappear for a few seconds, which Windows would respond to by
+    // migrating all VDD-hosted windows (browser, IDE, ...) onto the
+    // physical display. Those windows save the new position and end up
+    // off-screen from phantom's capture viewport. Skipping the reinstall
+    // when the driver is already registered avoids the window migration
+    // entirely. For a full wipe run `--uninstall-vdd` explicitly.
+    if vdd_device_present() {
+        println!("  Virtual Display Driver already installed — skipping reinstall");
+        println!("  (use --uninstall-vdd to force full removal)");
+        return Ok(());
+    }
+
     let vdd_dir = install_dir.join("vdd");
     std::fs::create_dir_all(&vdd_dir).context("create vdd dir")?;
 
@@ -1594,10 +1627,14 @@ pub fn uninstall_service() -> anyhow::Result<()> {
         anyhow::bail!("sc delete failed with {status}. Run as Administrator.");
     }
 
-    // Remove Virtual Display Driver
-    let install_dir = std::path::PathBuf::from(r"C:\Program Files\Phantom");
-    if let Err(e) = uninstall_vdd(&install_dir) {
-        println!("  Warning: VDD uninstall failed: {e}");
+    // Intentionally *not* removing the Virtual Display Driver here — we
+    // want `--uninstall` to be safe to run as part of an upgrade. The
+    // previous behaviour (always removing VDD) caused every upgrade to
+    // shuffle user windows onto the physical display while VDD was
+    // briefly absent, leaving those windows off-screen after reinstall.
+    // For a full wipe, operators call `--uninstall-vdd` explicitly.
+    if vdd_device_present() {
+        println!("  (Virtual Display Driver left in place; use --uninstall-vdd to remove it)");
     }
 
     // Clean up schtasks