Add Explicit Session Exit Controls Mini-Features ä2+3

src/admin_ssh_console.c

@@ -460,6 +460,28 @@ static void report_command_result(esp_err_t error, int command_result)
     }
 }
 
+static int command_exit(int argc, char **argv)
+{
+    (void)argv;
+    if (argc != 1) {
+        printf("Usage: exit\n");
+        return 1;
+    }
+    if (!admin_ssh_console_dispatch_is_remote()) {
+        printf("The exit command is available only from an administrative SSH session.\n");
+        return 1;
+    }
+
+    esp_err_t error = admin_ssh_console_dispatch_defer(
+        ADMIN_SSH_DEFER_DISCONNECT, s_dispatch_token.session_id);
+    if (error != ESP_OK) {
+        printf("Could not schedule SSH session close: %s\n", esp_err_to_name(error));
+        return 1;
+    }
+    printf("SSH session close scheduled after output drains.\n");
+    return 0;
+}
+
 static void dispatch_registered_command(admin_request_t *request)
 {
     FILE *saved_stdout = stdout;
@@ -724,6 +746,18 @@ esp_err_t admin_ssh_console_init(void)
     return ESP_OK;
 }
 
+esp_err_t admin_ssh_console_register_commands(void)
+{
+    const esp_console_cmd_t command = {
+        .command = "exit",
+        .help = "Close the current administrative SSH session",
+        .hint = NULL,
+        .func = &command_exit,
+        .argtable = NULL,
+    };
+    return esp_console_cmd_register(&command);
+}
+
 esp_err_t admin_ssh_console_start_uart_frontend(void)
 {
     taskENTER_CRITICAL(&s_lock);
@@ -1003,10 +1037,15 @@ bool admin_ssh_console_feed_input(const admin_ssh_console_token_t *token,
             secure_wipe(completed, sizeof(completed));
             continue;
         }
-        if (value == '\r' || value == '\n') {
+        bool exit_requested = value == 0x04U && session->input_length == 0U;
+        if (value == '\r' || value == '\n' || exit_requested) {
             session->discard_next_lf = value == '\r';
-            history_commit_locked(session);
-            memcpy(request.line, session->input, session->input_length);
+            if (exit_requested) {
+                memcpy(request.line, "exit", sizeof("exit"));
+            } else {
+                history_commit_locked(session);
+                memcpy(request.line, session->input, session->input_length);
+            }
             request.origin = ADMIN_REQUEST_SSH;
             request.token = *token;
             request.principal = session->principal;
@@ -1015,8 +1054,10 @@ bool admin_ssh_console_feed_input(const admin_ssh_console_token_t *token,
             session->input_cursor = 0U;
             session->history_position = -1;
             session->command_pending = true;
-            (void)append_output_locked(session, (const uint8_t *)"\r\n",
-                                       sizeof("\r\n") - 1U);
+            (void)append_output_locked(session,
+                                       (const uint8_t *)(exit_requested ? "^D\r\n" : "\r\n"),
+                                       exit_requested ? sizeof("^D\r\n") - 1U
+                                                      : sizeof("\r\n") - 1U);
             submit = true;
         } else if (value == 0x03U) {
             secure_wipe(session->input, sizeof(session->input));