CrossShell 0.2.0

CrossShell 0.2.0. The host agent can now be started on a server by another app for one session, and is published here as standalone binaries: SecureShell Go's remote desktop uses them.

Engine

• Protocol: CAP_DEFLATE (caps bit 0) and tile encoding 4, Deflate:
  a zlib stream (RFC 1950) of the same BGRX bytes a Zstd tile carries. A
  viewer that sets the bit in Hello.caps gets lossless tiles as Deflate
  instead of Zstd; the host answers Welcome.caps = Hello.caps & host caps.
  Viewers sending 0, CrossShell's own included, get exactly what they got
  before. The reserved CopyPrev encoding moves to 5.
• Host flags for remote-launched agents (SecureShell Go):
  • --runtime-dir DIR: host.json, the instance lock, status.json and
    the log go in DIR (created 0700, host.json 0600).
  • --exit-when-idle SECS: exit when no viewer connected within SECS of
    start, or SECS after the last viewer left.
  • --no-notify: see below.
• Connect notification: while a viewer is connected the host shows
  "Your screen is being viewed (and controlled) from ": a desktop
  notification on Linux, a notification-area balloon (toast) on Windows.
• Linux build flavours: PipeWire is now a default cargo feature. Without
  it the agent has the X11 backend only, links no C library and builds as a
  fully static musl binary. --version names the backends of the build.
• scripts/build-agents.sh builds the standalone agents (Linux x86_64 and
  aarch64, full and X11-only; Windows x64 and arm64) into dist/agents/
  with SHA256SUMS.
• crossshell-proto example ssgo_fixtures writes golden fixtures (encoded
  frames, expected pixels, every message type) for other implementations of
  the protocol.

Arm64 (prepared as 0.1.2, first released here)

Added

• Linux arm64 (aarch64) and Windows 11 on ARM (arm64) builds:
  crossshell-<version>-linux-arm64.tar.gz and
  crossshell-<version>-windows-arm64.zip, built natively next to the x64
  ones. The application is unchanged.
• The snap builds for arm64 as well as amd64.
• CI builds, tests and smoke-runs the engine and the app on native runners of
  each architecture, checks that every binary in the packages is the right
  architecture, and attaches the tarballs and zips of both architectures, with
  SHA256SUMS, to a published release without replacing any file that is
  already on it.

Changed

• scripts/build-linux.sh builds for the architecture of the machine it runs
  on, and scripts/package-windows.ps1 packs the Windows zip for the
  architecture of the machine it runs on.
• The snap's PipeWire plugin paths follow the architecture the snap is built
  for.

Standalone agents

crossshell-host-* are the agent on its own, for apps that start it over SSH:

• Linux x86_64 and aarch64: full (Mutter, portal and X11; needs libpipewire-0.3).
• Linux x86_64 and aarch64 -x11: X11 only, fully static.
• Windows x64 and arm64.

Their sums are in crossshell-host-SHA256SUMS.

Guide: CrossShell on learn.dhivalabs.com: install steps, a beginner guide and troubleshooting.