fix(native): proot fast path turns off and greys out while running without proot

app/src/main/java/com/droiddeck/launcher/runtime/ProotFastPath.kt

@@ -12,15 +12,16 @@ object ProotFastPath {
     const val LIBRARY = "/usr/local/lib/libblfastpath.so"
     const val MAX_BINDS = 256
 
-    fun allows(preference: Boolean, noSeccomp: Boolean, source: String): Boolean =
-        preference && !noSeccomp && source == LinuxRuntime.PROOT_PACK
+    fun allows(preference: Boolean, noSeccomp: Boolean, source: String, nativeUserland: Boolean = false): Boolean =
+        preference && !noSeccomp && !nativeUserland && source == LinuxRuntime.PROOT_PACK
 
     fun enabled(context: Context): Boolean {
         val preference = SessionPrefs.prootFastPath(context)
         val noSeccomp = SessionPrefs.prootNoSeccomp(context)
+        val nativeUserland = SessionPrefs.nativeUserland(context)
         val source = LinuxRuntime.prootSource(context)
-        val on = allows(preference, noSeccomp, source)
-        if (preference && !noSeccomp && !on)
+        val on = allows(preference, noSeccomp, source, nativeUserland)
+        if (preference && !noSeccomp && !nativeUserland && !on)
             Log.i(TAG, "proot: fast path off - binary is $source, not the patched proot")
         return on
     }

app/src/main/java/com/droiddeck/launcher/session/SessionFiles.kt

@@ -264,7 +264,7 @@ object SessionFiles {
             if (patched > 0) Log.i(TAG, "native userland: $patched system call sites in ld.so and libc answer Android's blocked calls")
             com.droiddeck.launcher.runtime.NativeGuest.syncLibraryDirs(root)
         }
-        if (ProotFastPath.enabled(context) && !nativeUserland) {
+        if (ProotFastPath.enabled(context)) {
             val library = com.droiddeck.launcher.agent.AgentEnv.fastPathLibrary(context)
             preload.append(library + "\n")
             if (startsSession && library != ProotFastPath.LIBRARY) Log.i(TAG, "fast path preload: $library (debugging override)")

app/src/main/java/com/droiddeck/launcher/session/SessionService.kt

@@ -666,7 +666,7 @@ class SessionService : Service() {
 
         val binds = sessionBinds(controllersOn, fakeInputDir, sessionDir, guest, sessionRoot, runtimeDir)
         val nativeUserland = com.droiddeck.launcher.runtime.NativeGuest.enabled(this)
-        val fastPathKey = if (ProotFastPath.enabled(this) && !nativeUserland) {
+        val fastPathKey = if (ProotFastPath.enabled(this)) {
             val prootBinds = LinuxRuntime.binds(
                 this, sessionRoot, runtimeDir, Environment.getExternalStorageDirectory(), binds,
             )

app/src/main/java/com/droiddeck/launcher/ui/PerformanceDialog.kt

@@ -189,9 +189,13 @@ fun PerformancePage(
             )
             ToggleRow(
                 host, "fastpath", stringResource(R.string.perf_fastpath),
-                if (prootNoSeccomp) stringResource(R.string.perf_fastpath_needs_seccomp)
-                else stringResource(R.string.perf_fastpath_hint),
-                prootFastPath && !prootNoSeccomp, enabled = !prootNoSeccomp, onChange = onProotFastPath,
+                when {
+                    nativeUserland -> stringResource(R.string.perf_fastpath_needs_proot)
+                    prootNoSeccomp -> stringResource(R.string.perf_fastpath_needs_seccomp)
+                    else -> stringResource(R.string.perf_fastpath_hint)
+                },
+                prootFastPath && !prootNoSeccomp && !nativeUserland, enabled = !prootNoSeccomp && !nativeUserland,
+                onChange = onProotFastPath,
             )
             ToggleRow(
                 host, "nativeuserland", stringResource(R.string.perf_native_userland),

app/src/main/res/values/strings.xml

@@ -651,6 +651,7 @@
     <string name="perf_native_userland">Run without proot (experimental)</string>
     <string name="perf_native_userland_hint">Starts the Linux side directly on Android. Applies to the next session. Turn off if something fails to start.</string>
     <string name="perf_fastpath">proot fast path</string>
+    <string name="perf_fastpath_needs_proot">Not used without proot.</string>
     <string name="perf_fastpath_needs_seccomp">Needs proot\'s seccomp filter.</string>
     <string name="perf_fastpath_hint">Faster file lookups and less stutter. Turn off if a program can\'t find its files.</string>
     <string name="perf_cursor_composite">Draw the cursor inside gamescope</string>

app/src/test/java/com/droiddeck/launcher/runtime/ProotFastPathTest.kt

@@ -33,4 +33,8 @@ class ProotFastPathTest {
         assertFalse(ProotFastPath.allows(preference = false, noSeccomp = false, source = LinuxRuntime.PROOT_PACK))
         assertFalse(ProotFastPath.allows(preference = true, noSeccomp = true, source = LinuxRuntime.PROOT_PACK))
     }
+
+    @Test fun fastPathStaysOffWithoutProot() {
+        assertFalse(ProotFastPath.allows(preference = true, noSeccomp = false, source = LinuxRuntime.PROOT_PACK, nativeUserland = true))
+    }
 }