guard prefix and wine edits while their apps run

src/runner.js

@@ -5,6 +5,7 @@ const fs = require('fs')
 const { spawn } = require('child_process')
 const { DIRS } = require('./paths')
 const { prefixPath } = require('./prefixes')
+const { prefixNameForGame } = require('./library')
 
 // The fake Steam install Proton is pointed at through
 // STEAM_COMPAT_CLIENT_INSTALL_PATH. Both folders Proton links into its prefix
@@ -18,13 +19,6 @@ function ensureFakeSteam() {
   return fake
 }
 
-// The prefix a run will use, by NAME (buildEnv resolves the same fallback).
-function prefixNameFor(game) {
-  if (game && game.prefix) return game.prefix
-  const defs = require('./prefixes').listPrefixes()
-  return defs.default || 'default'
-}
-
 // Wine only ever repairs links that are BROKEN: a prefix that came from
 // another machine (or from an older PLWL) can still hold absolute links into
 // its build that happen to resolve here, and those would be synced out again.
@@ -32,7 +26,7 @@ function prefixNameFor(game) {
 // costs a single walk in the common (already relative) case.
 const healedPrefixes = new Set()
 async function healPrefixOnce(game) {
-  const name = prefixNameFor(game)
+  const name = prefixNameForGame(game)
   const key = `${name}\u0000${DIRS.BUILD}`
   if (!name || healedPrefixes.has(key)) return 0
   healedPrefixes.add(key)
@@ -78,11 +72,9 @@ function linkPrefix(compatData, prefixDir) {
 function buildEnv({ game, wine }) {
   const env = { ...process.env }
   const isProton = wine && wine.type === 'proton'
-  let prefixDir = game.prefix ? prefixPath(game.prefix) : null
-  if (!prefixDir) {
-    const defs = require('./prefixes').listPrefixes()
-    prefixDir = prefixPath(defs.default || 'default')
-  }
+  // same fallback the games service snapshots into its running entries
+  // (library.prefixNameForGame), so in-use checks always name this folder
+  const prefixDir = prefixPath(prefixNameForGame(game))
 
   if (isProton) {
     const fakeSteam = ensureFakeSteam()