LibCore: Improve the TempFile wrapper

- We were using primitive versions of mkstemp and mkdtemp, they have
  been converted to use LibCore::System.
- If an error occurred whilst creating a temporary directory or file, it
  was thrown and the program would crash. Now, we use ErrorOr<T> so that
  the caller can handle the error accordingly
- The `Type` enumeration has been made private, and `create_temp` has
  been "split" (although rewritten) into create_temp_directory and
  create_temp_file. The old pattern of TempFile::create_temp(Type::File)
  felt a bit awkward, and TempFile::create_temp_file() feels a bit nicer
  to use! :^)

Once the Core::Filesystem PR is merged (#17789), it would be better for
this helper to be merged in with that. But until then, this is a nice
improvement.

Userland/Libraries/LibCore/TempFile.h

@@ -1,37 +1,41 @@
 /*
- * Copyright (c) 2020-2021, the SerenityOS developers.
+ * Copyright (c) 2020-2023, the SerenityOS developers.
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #pragma once
 
-#include <AK/DeprecatedString.h>
-#include <AK/Noncopyable.h>
+#include <AK/Error.h>
+#include <AK/NonnullOwnPtr.h>
+#include <AK/String.h>
 
 namespace Core {
 
 class TempFile {
-    AK_MAKE_NONCOPYABLE(TempFile);
-    AK_MAKE_NONMOVABLE(TempFile);
 
 public:
-    enum class Type {
-        File,
-        Directory
-    };
+    static ErrorOr<NonnullOwnPtr<TempFile>> create_temp_directory();
+    static ErrorOr<NonnullOwnPtr<TempFile>> create_temp_file();
 
-    static NonnullOwnPtr<TempFile> create(Type = Type::File);
     ~TempFile();
 
-    DeprecatedString path() const { return m_path; }
+    String const& path() const { return m_path; }
 
 private:
-    TempFile(Type);
-    static DeprecatedString create_temp(Type);
+    enum class Type {
+        Directory,
+        File
+    };
 
-    Type m_type { Type::File };
-    DeprecatedString m_path;
+    TempFile(Type type, String path)
+        : m_type(type)
+        , m_path(move(path))
+    {
+    }
+
+    Type m_type;
+    String m_path;
 };
 
 }