Move terminal writes off main thread

README.md

@@ -19,7 +19,8 @@ APIs directly:
   and kill session through HTTP API
 - open one live terminal viewer through `/ws/terminal`
 - native `/ws/events` listener for session invalidation and hook notifications
-- selectable GitHub or Gitea update manifest source
+- selectable Gitea or GitHub update source, defaulting to Gitea for mobile
+  reachability
 - native Tools page for health, server status, timeline, preferences, hook
   events, image file/URL upload, image preview info, and native image preview
   display
@@ -93,10 +94,10 @@ https://github.com/neatstudio/tmux-browser-android/releases/latest/download/tmux
 https://github.com/neatstudio/tmux-browser-android/releases/latest/download/latest.json
 ```
 
-Those GitHub links are the primary public install/update channel. Gitea releases
-are mirrored as a second public source. This Gitea instance does not support the
-GitHub-style `/releases/latest/download/...` URL, so the app uses the Gitea
-Release API as the stable Gitea update entrypoint.
+Gitea is the app's default install/update channel because phones may not be able
+to reach GitHub reliably. GitHub remains an optional public source. This Gitea
+instance does not support the GitHub-style `/releases/latest/download/...` URL,
+so the app uses the Gitea Release API as the stable Gitea update entrypoint.
 
 Plain branch builds only create Actions artifacts; they are useful for CI
 verification, but releases are the stable download/update channel.
@@ -146,28 +147,24 @@ release manifest automatically, downloads the newer APK, verifies its SHA-256,
 then opens Android's package installer. The user still has to approve the
 install, and Android 8+ may require allowing this app to install unknown apps.
 
-The default update manifest is:
+The default update source is the Gitea Release API:
+
+```text
+https://gitea.neatcn.com/api/v1/repos/tmux/tmux-browser-android/releases/latest
+```
+
+The default source resolves `latest.json` and `tmux-android.apk` from Gitea
+release assets, so APK downloads do not require GitHub. The optional GitHub
+manifest is:
 
 ```text
 https://github.com/neatstudio/tmux-browser-android/releases/latest/download/latest.json
 ```
 
-The public manual APK download is:
-
-```text
-https://github.com/neatstudio/tmux-browser-android/releases/latest/download/tmux-android.apk
-```
-
 The app checks only the selected update source. It does not probe GitHub and
 Gitea during the same update check. Choose the source in the app's `Update`
 page, or use a custom manifest/API URL.
 
-The built-in Gitea API endpoint is:
-
-```text
-https://gitea.neatcn.com/api/v1/repos/tmux/tmux-browser-android/releases/latest
-```
-
 Gitea tag-specific assets are also public, for example:
 
 ```text

app/build.gradle.kts

@@ -9,6 +9,8 @@ val repoSlug = providers.gradleProperty("repoSlug")
 val defaultServerUrl = providers.gradleProperty("defaultServerUrl")
     .orElse("http://100.89.0.116:3000")
 val defaultUpdateUrl = providers.gradleProperty("defaultUpdateUrl")
+    .orElse("https://gitea.neatcn.com/api/v1/repos/tmux/tmux-browser-android/releases/latest")
+val defaultGithubUpdateUrl = providers.gradleProperty("defaultGithubUpdateUrl")
     .orElse("https://github.com/${repoSlug.get()}/releases/latest/download/latest.json")
 val defaultGiteaUpdateUrl = providers.gradleProperty("defaultGiteaUpdateUrl")
     .orElse("https://gitea.neatcn.com/api/v1/repos/tmux/tmux-browser-android/releases/latest")
@@ -36,6 +38,7 @@ android {
 
         buildConfigField("String", "DEFAULT_SERVER_URL", "\"${defaultServerUrl.get()}\"")
         buildConfigField("String", "DEFAULT_UPDATE_URL", "\"${defaultUpdateUrl.get()}\"")
+        buildConfigField("String", "DEFAULT_GITHUB_UPDATE_URL", "\"${defaultGithubUpdateUrl.get()}\"")
         buildConfigField("String", "DEFAULT_GITEA_UPDATE_URL", "\"${defaultGiteaUpdateUrl.get()}\"")
         buildConfigField("String", "DEFAULT_APK_URL", "\"${defaultApkUrl.get()}\"")
         buildConfigField("String", "DEFAULT_RELEASE_PAGE_URL", "\"${defaultReleasePageUrl.get()}\"")

app/src/main/java/com/neatstudio/tmuxandroid/MainActivity.java

@@ -60,6 +60,7 @@ public final class MainActivity extends Activity {
     private static final int MAX_TERMINAL_CHARS = 40_000;
     private static final long TERMINAL_RENDER_INTERVAL_MS = 80L;
     private static final String OLD_LOCAL_DEFAULT_URL = "http://127.0.0.1:3000";
+    private static final String OLD_GITHUB_DEFAULT_UPDATE_URL = "https://github.com/neatstudio/tmux-browser-android/releases/latest/download/latest.json";
     private static final String DEFAULT_TAILSCALE_URL = "http://100.89.0.116:3000";
     private static final String PAGE_SESSIONS = "Sessions";
     private static final String PAGE_PROJECTS = "Projects";
@@ -116,6 +117,7 @@ public final class MainActivity extends Activity {
                     .putBoolean("tailscale_defaults_applied_v1", true)
                     .apply();
         }
+        migrateDefaultUpdateSourceToGitea();
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
             getWindow().setStatusBarColor(Color.rgb(17, 20, 24));
             getWindow().setNavigationBarColor(Color.rgb(17, 20, 24));
@@ -1438,8 +1440,8 @@ public final class MainActivity extends Activity {
                 .append(prefs.getString("update_url", BuildConfig.DEFAULT_UPDATE_URL))
                 .append('\n');
         text.append("Available sources:\n");
-        text.append("GitHub: ").append(BuildConfig.DEFAULT_UPDATE_URL).append('\n');
-        text.append("Gitea: ").append(BuildConfig.DEFAULT_GITEA_UPDATE_URL).append('\n');
+        text.append("Gitea default: ").append(BuildConfig.DEFAULT_GITEA_UPDATE_URL).append('\n');
+        text.append("GitHub optional: ").append(BuildConfig.DEFAULT_GITHUB_UPDATE_URL).append('\n');
         text.append('\n');
         text.append(permissionSummary());
 
@@ -1476,17 +1478,17 @@ public final class MainActivity extends Activity {
 
     private void showUpdateSourcePicker() {
         String[] items = {
-                "GitHub: " + BuildConfig.DEFAULT_UPDATE_URL,
-                "Gitea: " + BuildConfig.DEFAULT_GITEA_UPDATE_URL,
+                "Gitea default: " + BuildConfig.DEFAULT_GITEA_UPDATE_URL,
+                "GitHub optional: " + BuildConfig.DEFAULT_GITHUB_UPDATE_URL,
                 "Custom URL"
         };
         new AlertDialog.Builder(this)
                 .setTitle("Update source")
                 .setItems(items, (dialog, which) -> {
                     if (which == 0) {
-                        setUpdateUrl(BuildConfig.DEFAULT_UPDATE_URL);
-                    } else if (which == 1) {
                         setUpdateUrl(BuildConfig.DEFAULT_GITEA_UPDATE_URL);
+                    } else if (which == 1) {
+                        setUpdateUrl(BuildConfig.DEFAULT_GITHUB_UPDATE_URL);
                     } else {
                         promptText("Custom update manifest", "https://.../latest.json", prefs.getString("update_url", BuildConfig.DEFAULT_UPDATE_URL), this::setUpdateUrl);
                     }
@@ -1504,6 +1506,15 @@ public final class MainActivity extends Activity {
         }
     }
 
+    private void migrateDefaultUpdateSourceToGitea() {
+        String current = prefs.getString("update_url", "");
+        if (current == null || current.trim().isEmpty() || OLD_GITHUB_DEFAULT_UPDATE_URL.equals(current.trim())) {
+            prefs.edit()
+                    .putString("update_url", BuildConfig.DEFAULT_GITEA_UPDATE_URL)
+                    .apply();
+        }
+    }
+
     private void probeServerProfiles() {
         progressBar.setVisibility(View.VISIBLE);
         setStatus("Probing Tailscale APIs...");

app/src/main/java/com/neatstudio/tmuxandroid/TerminalSocketClient.java

@@ -12,6 +12,9 @@ import java.nio.charset.StandardCharsets;
 import java.security.MessageDigest;
 import java.security.SecureRandom;
 import java.util.Arrays;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.RejectedExecutionException;
 
 import javax.net.ssl.SSLSocketFactory;
 
@@ -25,6 +28,8 @@ final class TerminalSocketClient {
 
     private final Object writeLock = new Object();
     private final Listener listener;
+    private final ExecutorService writeExecutor = Executors.newSingleThreadExecutor(runnable ->
+            new Thread(runnable, "terminal-ws-write"));
     private Socket socket;
     private BufferedInputStream input;
     private BufferedOutputStream output;
@@ -42,32 +47,34 @@ final class TerminalSocketClient {
     }
 
     void sendInput(String data) {
-        sendMessage("input", "data", data);
+        sendMessageAsync("input", "data", data);
     }
 
     void resize(int cols, int rows) {
-        sendMessage("resize", "cols", cols, "rows", rows);
+        sendMessageAsync("resize", "cols", cols, "rows", rows);
     }
 
     void scroll(int lines) {
-        sendMessage("scroll", "lines", lines);
+        sendMessageAsync("scroll", "lines", lines);
     }
 
     void clearHistory() {
-        sendMessage("clear-history");
+        sendMessageAsync("clear-history");
     }
 
     void close() {
         closed = true;
         try {
-            sendFrame(8, new byte[0]);
-        } catch (Exception ignored) {
-        }
-        try {
-            if (socket != null) {
-                socket.close();
-            }
-        } catch (Exception ignored) {
+            writeExecutor.execute(() -> {
+                try {
+                    sendFrame(8, new byte[0]);
+                } catch (Exception ignored) {
+                }
+                closeSocketQuietly();
+            });
+            writeExecutor.shutdown();
+        } catch (RejectedExecutionException ignored) {
+            closeSocketQuietly();
         }
     }
 
@@ -82,7 +89,7 @@ final class TerminalSocketClient {
             input = new BufferedInputStream(socket.getInputStream());
             output = new BufferedOutputStream(socket.getOutputStream());
             handshake(uri);
-            sendMessage(
+            sendMessageSync(
                     "attach",
                     "tabId", "android-" + System.currentTimeMillis(),
                     "sessionName", sessionName,
@@ -98,12 +105,8 @@ final class TerminalSocketClient {
         } finally {
             closed = true;
             listener.onClosed();
-            try {
-                if (socket != null) {
-                    socket.close();
-                }
-            } catch (Exception ignored) {
-            }
+            closeSocketQuietly();
+            writeExecutor.shutdownNow();
         }
     }
 
@@ -243,7 +246,7 @@ final class TerminalSocketClient {
         }
     }
 
-    private void sendJson(JSONObject object) {
+    private void sendJsonSync(JSONObject object) {
         try {
             sendFrame(1, object.toString().getBytes(StandardCharsets.UTF_8));
         } catch (Exception error) {
@@ -253,14 +256,21 @@ final class TerminalSocketClient {
         }
     }
 
-    private void sendMessage(String type, Object... keyValues) {
+    private void sendMessageAsync(String type, Object... keyValues) {
+        try {
+            writeExecutor.execute(() -> sendMessageSync(type, keyValues));
+        } catch (RejectedExecutionException ignored) {
+        }
+    }
+
+    private void sendMessageSync(String type, Object... keyValues) {
         try {
             JSONObject object = new JSONObject();
             object.put("type", type);
             for (int i = 0; i + 1 < keyValues.length; i += 2) {
                 object.put(String.valueOf(keyValues[i]), keyValues[i + 1]);
             }
-            sendJson(object);
+            sendJsonSync(object);
         } catch (Exception error) {
             if (!closed) {
                 listener.onError(error.getMessage() == null ? error.toString() : error.getMessage());
@@ -268,6 +278,15 @@ final class TerminalSocketClient {
         }
     }
 
+    private void closeSocketQuietly() {
+        try {
+            if (socket != null) {
+                socket.close();
+            }
+        } catch (Exception ignored) {
+        }
+    }
+
     private void sendFrame(int opcode, byte[] payload) throws Exception {
         synchronized (writeLock) {
             if (output == null) {

docs/android-client-notes.md

@@ -87,7 +87,7 @@ Implemented now:
   preview display
 - GitHub Actions APK build
 - release manifest `latest.json`
-- selected-source update checks; GitHub and Gitea are not probed in the same
+- selected-source update checks; Gitea and GitHub are not probed in the same
   update check
 - one-download-per-version APK cache, SHA-256 verification, and installer
   handoff
@@ -102,10 +102,10 @@ open Android's package installer, but the user must approve the install. On
 Android 8+, the user may also need to allow this app to install unknown apps.
 
 The app checks exactly one update source per run: the selected manifest/API URL.
-GitHub is the default public source. Gitea is available as a public mirror, but
-the app does not fall back across both providers during a normal check. This
-keeps update behavior predictable on mobile networks and avoids duplicate
-provider checks.
+Gitea is the default public source because phones may not reach GitHub reliably.
+GitHub is available as an optional public source, but the app does not fall back
+across both providers during a normal check. This keeps update behavior
+predictable on mobile networks and avoids duplicate provider checks.
 
 Downloaded APKs are cached by `versionCode`. If a cached APK exists and its
 SHA-256 matches the manifest, the app reuses it instead of downloading the same