Add ACTION_SERVICE_STOP intent to only stop a single AppShell

app/src/main/java/com/termux/app/TermuxService.java

@@ -154,6 +154,10 @@ public int onStartCommand(Intent intent, int flags, int startId) {
                     Logger.logDebug(LOG_TAG, "ACTION_SERVICE_EXECUTE intent received");
                     actionServiceExecute(intent);
                     break;
+                case TERMUX_SERVICE.ACTION_SERVICE_STOP:
+                    Logger.logDebug(LOG_TAG, "ACTION_SERVICE_STOP intent received");
+                    actionServiceStop(intent);
+                    break;
                 default:
                     Logger.logError(LOG_TAG, "Invalid action: \"" + action + "\"");
                     break;
@@ -354,6 +358,25 @@ private void actionReleaseWakeLock(boolean updateNotification) {
         Logger.logDebug(LOG_TAG, "WakeLocks released successfully");
     }
 
+    private void actionServiceStop(Intent intent) {
+        if (intent == null) {
+            Logger.logError(LOG_TAG, "Ignoring null intent to actionServiceStop");
+            return;
+        }
+
+        String shellName = IntentUtils.getStringExtraIfSet(intent, TERMUX_SERVICE.EXTRA_SHELL_NAME, null);
+        if (shellName == null) {
+            Logger.logError(LOG_TAG, "Ignoring intent since it did not contain explicit shell name");
+            return;
+        }
+
+        int gracePeriod = IntentUtils.getIntegerExtraIfSet(intent, TERMUX_SERVICE.EXTRA_TERMINATE_GRACE_PERIOD, 5000);
+        AppShell appShell = getTermuxTaskForShellName(shellName);
+        if (appShell != null) {
+            appShell.terminateIfExecuting(getApplicationContext(), gracePeriod, true);
+        }
+    }
+
     /** Process {@link TERMUX_SERVICE#ACTION_SERVICE_EXECUTE} intent to execute a shell command in
      * a foreground TermuxSession or in a background TermuxTask. */
     private void actionServiceExecute(Intent intent) {

termux-shared/src/main/java/com/termux/shared/shell/command/runner/app/AppShell.java

@@ -1,6 +1,7 @@
 package com.termux.shared.shell.command.runner.app;
 
 import android.content.Context;
+import android.os.Handler;
 import android.system.ErrnoException;
 import android.system.Os;
 import android.system.OsConstants;
@@ -245,6 +246,37 @@ private void executeInner(@NonNull final Context context) throws IllegalThreadSt
         AppShell.processAppShellResult(this, null);
     }
 
+    /**
+     * Terminate this {@link AppShell} by sending a {@link OsConstants#SIGTERM} to its {@link #mProcess}
+     * if it is still executing. After {@code gracePeriodMsec} milliseconds {@link OsConstants#SIGTERM} is
+     * signalled.
+     *
+     * @param context The {@link Context} for operations.
+     * @param gracePeriodMsec The delay after which a SIGKILL is send.
+     * @param processResult If set to {@code true}, then the {@link #processAppShellResult(AppShell, ExecutionCommand)}
+     *                      will be called to process the failure.
+     */
+    public void terminateIfExecuting(@NonNull final Context context, long gracePeriodMsec, boolean processResult) {
+        if (gracePeriodMsec == 0) {
+            killIfExecuting(context, processResult);
+            return;
+        }
+
+        // If execution command has already finished executing, then no need to process results or sending any signals
+        if (mExecutionCommand.hasExecuted()) {
+            Logger.logDebug(LOG_TAG, "Ignoring sending SIGTERM or SIGKILL to \"" + mExecutionCommand.getCommandIdAndLabelLogString() + "\" AppShell since it has already finished executing");
+            return;
+        }
+
+        Logger.logDebug(LOG_TAG, "Send SIGTERM to \"" + mExecutionCommand.getCommandIdAndLabelLogString() + "\" AppShell");
+
+        if (mExecutionCommand.isExecuting()) {
+            term();
+        }
+
+        (new Handler()).postDelayed(() -> killIfExecuting(context, processResult), gracePeriodMsec);
+    }
+
     /**
      * Kill this {@link AppShell} by sending a {@link OsConstants#SIGILL} to its {@link #mProcess}
      * if its still executing.
@@ -274,6 +306,20 @@ public void killIfExecuting(@NonNull final Context context, boolean processResul
         }
     }
 
+
+    /**
+     * Terminate this {@link AppShell} by sending a {@link OsConstants#SIGTERM} to its {@link #mProcess}.
+     */
+    public void term() {
+        int pid = ShellUtils.getPid(mProcess);
+        try {
+            // Send SIGKILL to process
+            Os.kill(pid, OsConstants.SIGTERM);
+        } catch (ErrnoException e) {
+            Logger.logWarn(LOG_TAG, "Failed to send SIGTERM to \"" + mExecutionCommand.getCommandIdAndLabelLogString() + "\" AppShell with pid " + pid + ": " + e.getMessage());
+        }
+    }
+
     /**
      * Kill this {@link AppShell} by sending a {@link OsConstants#SIGILL} to its {@link #mProcess}.
      */

termux-shared/src/main/java/com/termux/shared/termux/TermuxConstants.java

@@ -993,6 +993,9 @@ public static final class TERMUX_SERVICE {
             /** Intent action to execute command with TERMUX_SERVICE */
             public static final String ACTION_SERVICE_EXECUTE = TERMUX_PACKAGE_NAME + ".service_execute"; // Default: "com.termux.service_execute"
 
+            /** Intent action to stop command execution with TERMUX_SERVICE */
+            public static final String ACTION_SERVICE_STOP = TERMUX_PACKAGE_NAME + ".service_execution_stop"; // Default: "com.termux.service_execution_stop"
+
             /** Uri scheme for paths sent via intent to TERMUX_SERVICE */
             public static final String URI_SCHEME_SERVICE_EXECUTE = TERMUX_PACKAGE_NAME + ".file"; // Default: "com.termux.file"
             /** Intent {@code String[]} extra for arguments to the executable of the command for the TERMUX_SERVICE.ACTION_SERVICE_EXECUTE intent */
@@ -1046,6 +1049,9 @@ public static final class TERMUX_SERVICE {
              * be created in {@link #EXTRA_RESULT_DIRECTORY} if {@link #EXTRA_RESULT_SINGLE_FILE} is
              * {@code false} for the TERMUX_SERVICE.ACTION_SERVICE_EXECUTE intent */
             public static final String EXTRA_RESULT_FILES_SUFFIX = TERMUX_PACKAGE_NAME + ".execute.result_files_suffix"; // Default: "com.termux.execute.result_files_suffix"
+            /** Intent {@code long} extra for graceperiod between SIGTERM and SIGKILL
+             * for the TERMUX_SERVICE.ACTION_SERVICE_STOP intent */
+            public static final String EXTRA_TERMINATE_GRACE_PERIOD = TERMUX_PACKAGE_NAME + ".execute.stop.delay"; // Default: "com.termux.execute.stop.delay"