SDL3-CS/SDL3-CS/SDL3.cs

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.

using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Text;

namespace SDL
{
    public static unsafe partial class SDL3
    {
        /// <summary>
        /// Allocates a managed <c>string</c> and copies all characters up to the first null character from an unmanaged UTF-8 string into it.
        /// </summary>
        /// <param name="ptr">The address of the first character of the unmanaged string.</param>
        /// <param name="free">Whether to free the pointer after copying the string.</param>
        /// <returns>
        /// A managed string that holds a copy of the unmanaged string if the value of the <paramref name="ptr"/> parameter is not <c>null</c>; otherwise, this method returns <c>null</c>.
        /// </returns>
        public static string? PtrToStringUTF8(byte* ptr, bool free = false)
        {
            string? s = Marshal.PtrToStringUTF8((IntPtr)ptr);

            if (free)
                SDL_free(ptr);

            return s;
        }

        /// <summary>
        /// UTF8 encodes a managed <c>string</c> to a <c>byte</c> array suitable for use in <c>ReadOnlySpan&lt;byte&gt;</c> parameters of SDL functions.
        /// </summary>
        /// <param name="s">The <c>string</c> to encode.</param>
        /// <returns>A null-terminated byte array.</returns>
        public static byte[] UTF8GetBytes(string s)
        {
            byte[] array = Encoding.UTF8.GetBytes(s + '\0');
            Debug.Assert(array[^1] == '\0');
            return array;
        }
    }
}