Userland: Enhance jail-attach utility to support existing and new jails

The Core::System::create_jail function already provided the new jail
index as a result, so it was just a matter of using it when calling the
LibCore join_jail function to use the new jail.

1 files changed, 14 insertions, 3 deletions

diff --git a/Userland/Utilities/jail-attach.cpp b/Userland/Utilities/jail-attach.cpp
index ba09dafc49..781359fcaa 100644
--- a/Userland/Utilities/jail-attach.cpp
+++ b/Userland/Utilities/jail-attach.cpp
@@ -11,18 +11,29 @@
 
 ErrorOr<int> serenity_main(Main::Arguments arguments)
 {
-    unsigned jail_index = 0;
+    StringView new_jail_name;
     Vector<StringView> command;
+    Optional<size_t> existing_jail_index;
     Core::ArgsParser args_parser;
     bool preserve_env = false;
     args_parser.set_stop_on_first_non_option(true);
     args_parser.add_option(preserve_env, "Preserve user environment when running command", "preserve-env", 'E');
-    args_parser.add_positional_argument(jail_index, "Jail Index", "jail index");
+    args_parser.add_option(new_jail_name, "Create a new jail with a name", "jail-name", 'n', "New jail name");
+    args_parser.add_option(existing_jail_index, "Use an existing jail index instead of creating new jail", "jail-index", 'i', "Existing jail index");
     args_parser.add_positional_argument(command, "Command to execute", "command");
     args_parser.parse(arguments);
 
     TRY(Core::System::pledge("stdio rpath exec id jail tty"));
-    TRY(Core::System::join_jail(jail_index));
+
+    if (existing_jail_index.has_value() && !new_jail_name.is_null())
+        return Error::from_string_view("Can't launch process in a new jail with a name and use an existing jail index."sv);
+
+    if (existing_jail_index.has_value()) {
+        TRY(Core::System::join_jail(existing_jail_index.value()));
+    } else {
+        u64 new_jail_index = TRY(Core::System::create_jail(new_jail_name.is_null() ? ""sv : new_jail_name));
+        TRY(Core::System::join_jail(new_jail_index));
+    }
     TRY(Core::System::exec_command(command, preserve_env));
     return 0;
 }