Handle daemon startup failures

5 files changed, 31 insertions, 11 deletions

diff --git a/app/src/main/c/exec.c b/app/src/main/c/exec.c
index d665341..5a76177 100644
--- a/app/src/main/c/exec.c
+++ b/app/src/main/c/exec.c
@@ -36,5 +36,7 @@ Java_org_pacien_tincapp_commands_Executor_forkExec(JNIEnv *env, jclass class, jo
 
 JNIEXPORT jint JNICALL
 Java_org_pacien_tincapp_commands_Executor_wait(JNIEnv *env, jclass class, jint pid) {
-  return waitpid(pid, NULL, 0);
+  int status;
+  waitpid(pid, &status, 0);
+  return WIFEXITED(status) ? WEXITSTATUS(status) : -1;
 }
diff --git a/app/src/main/java/org/pacien/tincapp/commands/Executor.kt b/app/src/main/java/org/pacien/tincapp/commands/Executor.kt
index eb04f6d..fedd0d2 100644
--- a/app/src/main/java/org/pacien/tincapp/commands/Executor.kt
+++ b/app/src/main/java/org/pacien/tincapp/commands/Executor.kt
@@ -13,6 +13,7 @@ import java.io.InputStreamReader
  */
 internal object Executor {
   private const val FAILED = -1
+  private const val SUCCESS = 0
 
   class CommandExecutionException(msg: String) : Exception(msg)
 
@@ -26,17 +27,23 @@ internal object Executor {
   private external fun forkExec(argcv: Array<String>): Int
 
   /**
-   * @return FAILED (-1) on error, 0 on no-op, the supplied PID otherwise
+   * @return FAILED (-1) on error, the exit status of the process otherwise
    */
   private external fun wait(pid: Int): Int
 
   private fun read(stream: InputStream) = BufferedReader(InputStreamReader(stream)).readLines()
 
   fun forkExec(cmd: Command): CompletableFuture<Void> {
-    val pid = forkExec(cmd.asArray())
-    return when (pid) {
-      FAILED -> CompletableFuture.failedFuture(CommandExecutionException("Could not fork child process."))
-      else -> CompletableFuture.runAsync { wait(pid) }
+    val pid = forkExec(cmd.asArray()).also {
+      if (it == FAILED) throw CommandExecutionException("Could not fork child process.")
+    }
+
+    return CompletableFuture.runAsync {
+      when (wait(pid)) {
+        SUCCESS -> Unit
+        FAILED -> throw CommandExecutionException("Process terminated abnormally.")
+        else -> throw CommandExecutionException("Non-zero exit status code.")
+      }
     }
   }
 
diff --git a/app/src/main/java/org/pacien/tincapp/context/App.kt b/app/src/main/java/org/pacien/tincapp/context/App.kt
index 9fb910b..4a4a475 100644
--- a/app/src/main/java/org/pacien/tincapp/context/App.kt
+++ b/app/src/main/java/org/pacien/tincapp/context/App.kt
@@ -4,6 +4,7 @@ import android.app.Application
 import android.content.Context
 import android.content.Intent
 import android.net.Uri
+import android.os.Handler
 import android.support.annotation.StringRes
 import android.support.v7.app.AlertDialog
 import android.view.WindowManager
@@ -16,20 +17,23 @@ class App : Application() {
   override fun onCreate() {
     super.onCreate()
     appContext = applicationContext
+    handler = Handler()
   }
 
   companion object {
     private var appContext: Context? = null
+    private var handler: Handler? = null
 
     fun getContext() = appContext!!
     fun getResources() = getContext().resources!!
 
-    fun alert(@StringRes title: Int, msg: String, manualLink: String? = null) =
+    fun alert(@StringRes title: Int, msg: String, manualLink: String? = null) = handler!!.post {
       AlertDialog.Builder(getContext(), R.style.Theme_AppCompat_Dialog)
         .setTitle(title).setMessage(msg)
         .apply { if (manualLink != null) setNeutralButton(R.string.action_open_manual) { _, _ -> openURL(manualLink) } }
         .setPositiveButton(R.string.action_close, { _, _ -> Unit })
         .create().apply { window.setType(WindowManager.LayoutParams.TYPE_SYSTEM_ERROR) }.show()
+    }
 
     fun openURL(url: String) =
       appContext?.startActivity(Intent(Intent.ACTION_VIEW, Uri.parse(url)).addFlags(Intent.FLAG_ACTIVITY_NEW_TASK))
diff --git a/app/src/main/java/org/pacien/tincapp/service/TincVpnService.kt b/app/src/main/java/org/pacien/tincapp/service/TincVpnService.kt
index dfdbb32..223763d 100644
--- a/app/src/main/java/org/pacien/tincapp/service/TincVpnService.kt
+++ b/app/src/main/java/org/pacien/tincapp/service/TincVpnService.kt
@@ -94,12 +94,18 @@ class TincVpnService : VpnService() {
 
     val daemon = Tincd.start(netName, deviceFd.fd, privateKeys.first?.fd, privateKeys.second?.fd)
     setState(netName, interfaceCfg, deviceFd, daemon)
-    waitForDaemonStartup().thenRun {
+
+    waitForDaemonStartup().whenComplete { _, exception ->
       deviceFd.close()
       privateKeys.first?.close()
       privateKeys.second?.close()
-      Log.i(TAG, "tinc daemon started.")
-      broadcastEvent(Actions.EVENT_CONNECTED)
+
+      if (exception != null) {
+        reportError(resources.getString(R.string.message_daemon_exited, exception.cause!!.message!!), exception)
+      } else {
+        Log.i(TAG, "tinc daemon started.")
+        broadcastEvent(Actions.EVENT_CONNECTED)
+      }
     }
   }
 
@@ -132,7 +138,7 @@ class TincVpnService : VpnService() {
   private fun waitForDaemonStartup() =
     CompletableFuture
       .runAsync { Thread.sleep(SETUP_DELAY) }
-      .thenCompose { netName?.let { Tinc.pid(it) } ?: CompletableFuture.completedFuture(0) }
+      .thenCompose { if (daemon!!.isDone) daemon!! else CompletableFuture.runAsync { } }
 
   companion object {
     private const val SETUP_DELAY = 500L // ms
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index da64285..fed15f0 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -79,6 +79,7 @@
         <string name="message_starting_vpn">Starting VPN…</string>
         <string name="message_disconnecting_vpn">Disconnecting VPN…</string>
         <string name="message_passphrase_required">A passphrase is required to unlock the keyring.</string>
+        <string name="message_daemon_exited">Tinc daemon exited during startup:\n%1$s\n\nCheck the logs for more details.</string>
 
         <string name="value_none">none</string>
         <string name="value_yes">yes</string>