feat: WIP s6-overlay and friends

packages/scripts/pressure-vent.sh

@@ -0,0 +1,54 @@
+#!/bin/bash
+# Steam "Pressure Vessel" runtime eliminator.
+#
+# Valve ships various pre-packaged runtime environments for games to use.
+# They are cool, in a way: Most games "just work" with them.
+# However, such convenience comes at the cost of performance and sometimes reliability.
+#
+# Normally, I disable any and all such runtimes and install all the required dependencies myself.
+# However, running Windows games using Proton enforces use of a runtime.
+# That runtime is shipped in a "Pressure Vessel" container, which is more isolated.
+# The worst part is, user-supplied LD_PRELOAD and LD_LIBRARY_PATH are ignored due to that.
+# That means no primusrun/pvkrun/whatever for Windows games, which sucks.
+#
+# This little script's purpose is to cut "Pressure Vessel" out of game's command line.
+# Be warned that that gives you the ability *and responsibility* to manage the dependencies.
+# Place pressure-vent.sh after all " -- " in game's launch options, if any.
+# Placing e.g. "xterm -e" at the start of launch options is an easy way to see logs.
+# Examples:
+#   primusrun ~/pressure-vent.sh %command%
+#   xterm -e /full/path/to/pressure-vent.sh pvkrun %command%
+
+
+# Functions
+cmdprn() {
+	printf '%s:\n%q' "$1" "$2"
+	printf ' %q' "${@:3}"
+	printf '\n\n'
+}
+err() {
+	printf '%s\nPress Enter to quit.\n' "$1"
+	read
+	exit 1
+}
+
+# Debug
+cmdprn "Original command line" "$@"
+printf "LD_PRELOAD:\n%q\n\n" "$LD_PRELOAD"
+printf "LD_LIBRARY_PATH:\n%q\n\n" "$LD_LIBRARY_PATH"
+
+# Find Pressure Vessel arguments (between two first "--")
+((left=1))
+while [[ left -le $# && "${!left}" != "--" ]]; do
+	((left++))
+done
+((right=left+1))
+while [[ right -le $# && "${!right}" != "--" ]]; do
+	((right++))
+done
+[[ right -gt $# ]] && err 'Error processing command line.'
+# Cut them out
+set -- "${@:1:left}" "${@:right+1}"
+cmdprn "Processed command line" "$@"  # Debug
+
+exec "$@" || err "Game terminated with code $?."