libs/SDL2/docs/README-versions.md

+# Versioning
+
+## Since 2.23.0
+
+SDL follows an "odd/even" versioning policy, similar to GLib, GTK, Flatpak
+and older versions of the Linux kernel:
+
+* The major version (first part) increases when backwards compatibility
+    is broken, which will happen infrequently.
+
+* If the minor version (second part) is divisible by 2
+    (for example 2.24.x, 2.26.x), this indicates a version of SDL that
+    is believed to be stable and suitable for production use.
+
+    * In stable releases, the patchlevel or micro version (third part)
+        indicates bugfix releases. Bugfix releases should not add or
+        remove ABI, so the ".0" release (for example 2.24.0) should be
+        forwards-compatible with all the bugfix releases from the
+        same cycle (for example 2.24.1).
+
+    * The minor version increases when new API or ABI is added, or when
+        other significant changes are made. Newer minor versions are
+        backwards-compatible, but not fully forwards-compatible.
+        For example, programs built against SDL 2.24.x should work fine
+        with SDL 2.26.x, but programs built against SDL 2.26.x will not
+        necessarily work with 2.24.x.
+
+* If the minor version (second part) is not divisible by 2
+    (for example 2.23.x, 2.25.x), this indicates a development prerelease
+    of SDL that is not suitable for stable software distributions.
+    Use with caution.
+
+    * The patchlevel or micro version (third part) increases with
+        each prerelease.
+
+    * Each prerelease might add new API and/or ABI.
+
+    * Prereleases are backwards-compatible with older stable branches.
+        For example, 2.25.x will be backwards-compatible with 2.24.x.
+
+    * Prereleases are not guaranteed to be backwards-compatible with
+        each other. For example, new API or ABI added in 2.25.1
+        might be removed or changed in 2.25.2.
+        If this would be a problem for you, please do not use prereleases.
+
+    * Only upgrade to a prerelease if you can guarantee that you will
+        promptly upgrade to the stable release that follows it.
+        For example, do not upgrade to 2.23.x unless you will be able to
+        upgrade to 2.24.0 when it becomes available.
+
+    * Software distributions that have a freeze policy (in particular Linux
+        distributions with a release cycle, such as Debian and Fedora)
+        should usually only package stable releases, and not prereleases.
+
+## Before 2.23.0
+
+Older versions of SDL followed a similar policy, but instead of the
+odd/even rule applying to the minor version, it applied to the patchlevel
+(micro version, third part). For example, 2.0.22 was a stable release
+and 2.0.21 was a prerelease.

libs/SDL2/docs/README-visualc.md

+Using SDL with Microsoft Visual C++
+===================================
+
+### by Lion Kimbro with additions by James Turk
+
+You can either use the precompiled libraries from the [SDL](https://www.libsdl.org/download.php) web site, or you can build SDL
+yourself.
+
+### Building SDL
+
+0. To build SDL, your machine must, at a minimum, have the DirectX9.0c SDK installed. It may or may not be retrievable from
+the [Microsoft](https://www.microsoft.com) website, so you might need to locate it [online](https://duckduckgo.com/?q=directx9.0c+sdk+download&t=h_&ia=web).
+_Editor's note: I've been able to successfully build SDL using Visual Studio 2019 **without** the DX9.0c SDK_
+
+1. Open the Visual Studio solution file at `./VisualC/SDL.sln`.
+
+2. Your IDE will likely prompt you to upgrade this solution file to whatever later version of the IDE you're using. In the `Retarget Projects` dialog,
+all of the affected project files should be checked allowing you to use the latest `Windows SDK Version` you have installed, along with
+the `Platform Toolset`.
+
+If you choose *NOT* to upgrade to use the latest `Windows SDK Version` or `Platform Toolset`, then you'll need the `Visual Studio 2010 Platform Toolset`.
+
+3. Build the `.dll` and `.lib` files by right clicking on each project in turn (Projects are listed in the _Workspace_
+panel in the _FileView_ tab), and selecting `Build`.
+
+You may get a few warnings, but you should not get any errors.
+
+Later, we will refer to the following `.lib` and `.dll` files that have just been generated:
+
+-   `./VisualC/Win32/Debug/SDL2.dll` or `./VisualC/Win32/Release/SDL2.dll`
+-   `./VisualC/Win32/Debug/SDL2.lib` or `./VisualC/Win32/Release/SDL2.lib`
+-   `./VisualC/Win32/Debug/SDL2main.lib` or `./VisualC/Win32/Release/SDL2main.lib`
+
+_Note for the `x64` versions, just replace `Win32` in the path with `x64`_
+
+### Creating a Project with SDL
+
+- Create a project as a `Win32 Application`.
+
+- Create a C++ file for your project.
+
+- Set the C runtime to `Multi-threaded DLL` in the menu:
+`Project|Settings|C/C++                  tab|Code Generation|Runtime Library `.
+
+- Add the SDL `include` directory to your list of includes in the menu:
+`Project|Settings|C/C++ tab|Preprocessor|Additional include directories `
+
+*VC7 Specific: Instead of doing this, I find it easier to add the
+include and library directories to the list that VC7 keeps. Do this by
+selecting Tools|Options|Projects|VC++ Directories and under the "Show
+Directories For:" dropbox select "Include Files", and click the "New
+Directory Icon" and add the [SDLROOT]\\include directory (e.g. If you
+installed to c:\\SDL\\ add c:\\SDL\\include). Proceed to change the
+dropbox selection to "Library Files" and add [SDLROOT]\\lib.*
+
+The "include directory" I am referring to is the `./include` folder.
+
+Now we're going to use the files that we had created earlier in the *Build SDL* step.
+
+Copy the following file into your Project directory:
+
+-   `SDL2.dll`
+
+Add the following files to your project (It is not necessary to copy them to your project directory):
+
+-   `SDL2.lib`
+-   `SDL2main.lib`
+
+To add them to your project, right click on your project, and select
+`Add files to project`.
+
+**Instead of adding the files to your project, it is more desirable to add them to the linker options: Project|Properties|Linker|Command Line
+and type the names of the libraries to link with in the "Additional Options:" box. Note: This must be done for each build configuration
+(e.g. Release,Debug).**
+
+### Hello SDL2
+
+Here's a sample SDL snippet to verify everything is setup in your IDE:
+
+```
+    #include "SDL.h"
+
+    int main( int argc, char* argv[] )
+    {
+        const int WIDTH = 640;
+        const int HEIGHT = 480;
+        SDL_Window* window = NULL;
+        SDL_Renderer* renderer = NULL;
+
+        SDL_Init(SDL_INIT_VIDEO);
+        window = SDL_CreateWindow("SDL2 Test", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, WIDTH, HEIGHT, SDL_WINDOW_SHOWN);
+        renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
+
+        SDL_DestroyRenderer(renderer);
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        return 0;
+    }
+ ```
+
+### That's it!
+
+I hope that this document has helped you get through the most difficult part of using the SDL: installing it.
+Suggestions for improvements should be posted to the [Github Issues](https://github.com/libsdl-org/SDL/issues).
+
+### Credits
+
+Thanks to [Paulus Esterhazy](mailto:pesterhazy@gmx.net), for the work on VC++ port.
+
+This document was originally called "VisualC.txt", and was written by [Sam Lantinga](mailto:slouken@libsdl.org).
+
+Later, it was converted to HTML and expanded into the document that you see today by [Lion Kimbro](mailto:snowlion@sprynet.com).
+
+Minor Fixes and Visual C++ 7 Information (In Green) was added by [James Turk](mailto:james@conceptofzero.net)

libs/SDL2/docs/README-vita.md

+PS Vita
+=======
+SDL port for the Sony Playstation Vita and Sony Playstation TV
+
+Credit to
+* xerpi, cpasjuste and rsn8887 for initial (vita2d) port
+* vitasdk/dolcesdk devs
+* CBPS discord (Namely Graphene and SonicMastr)
+
+Building
+--------
+To build for the PSVita, make sure you have vitasdk and cmake installed and run:
+```
+   cmake -S. -Bbuild -DCMAKE_TOOLCHAIN_FILE=${VITASDK}/share/vita.toolchain.cmake -DCMAKE_BUILD_TYPE=Release
+   cmake --build build
+   cmake --install build
+```
+
+
+Notes
+-----
+* gles1/gles2 support and renderers are disabled by default and can be enabled by configuring with `-DVIDEO_VITA_PVR=ON`
+  These renderers support 720p and 1080i resolutions. These can be specified with:
+  `SDL_setenv("VITA_RESOLUTION", "720", 1);` and `SDL_setenv("VITA_RESOLUTION", "1080", 1);`
+* Desktop GL 1.X and 2.X support and renderers are also disabled by default and also can be enabled with `-DVIDEO_VITA_PVR=ON` as long as gl4es4vita is present in your SDK.
+  They support the same resolutions as the gles1/gles2 backends and require specifying `SDL_setenv("VITA_PVR_OGL", "1", 1);`
+  anytime before video subsystem initialization.
+* gles2 support via PIB is disabled by default and can be enabled by configuring with `-DVIDEO_VITA_PIB=ON`
+* By default SDL emits mouse events for touch events on every touchscreen.
+  Vita has two touchscreens, so it's recommended to use `SDL_SetHint(SDL_HINT_TOUCH_MOUSE_EVENTS, "0");` and handle touch events instead.
+  Individual touchscreens can be disabled with:
+  `SDL_setenv("VITA_DISABLE_TOUCH_FRONT", "1", 1);` and `SDL_setenv("VITA_DISABLE_TOUCH_BACK", "1", 1);`
+* Support for L2/R2/R3/R3 buttons, haptic feedback and gamepad led only available on PSTV, or when using external ds4 gamepad on vita.

libs/SDL2/docs/README-wince.md

 WinCE
 =====
-
-Windows CE is no longer supported by SDL.
-
-We have left the CE support in SDL 1.2 for those that must have it, and we
-have support for Windows Phone 8 and WinRT in SDL2, as of SDL 2.0.3.
-
---ryan.
-
+
+Windows CE is no longer supported by SDL.
+
+We have left the CE support in SDL 1.2 for those that must have it, and we
+have support for Windows Phone 8 and WinRT in SDL2, as of SDL 2.0.3.
+
+--ryan.
+

libs/SDL2/docs/README-windows.md

-Windows
-================================================================================
-
-================================================================================
-OpenGL ES 2.x support
-================================================================================
-
-SDL has support for OpenGL ES 2.x under Windows via two alternative 
-implementations. 
-The most straightforward method consists in running your app in a system with 
-a graphic card paired with a relatively recent (as of November of 2013) driver 
-which supports the WGL_EXT_create_context_es2_profile extension. Vendors known 
+# Windows
+
+## LLVM and Intel C++ compiler support
+
+SDL will build with the Visual Studio project files with LLVM-based compilers, such as the Intel oneAPI C++
+compiler, but you'll have to manually add the "-msse3" command line option
+to at least the SDL_audiocvt.c source file, and possibly others. This may
+not be necessary if you build SDL with CMake instead of the included Visual
+Studio solution.
+
+Details are here: https://github.com/libsdl-org/SDL/issues/5186
+
+
+## OpenGL ES 2.x support
+
+SDL has support for OpenGL ES 2.x under Windows via two alternative
+implementations.
+
+The most straightforward method consists in running your app in a system with
+a graphic card paired with a relatively recent (as of November of 2013) driver
+which supports the WGL_EXT_create_context_es2_profile extension. Vendors known
 to ship said extension on Windows currently include nVidia and Intel.
 
-The other method involves using the ANGLE library (https://code.google.com/p/angleproject/)
-If an OpenGL ES 2.x context is requested and no WGL_EXT_create_context_es2_profile
-extension is found, SDL will try to load the libEGL.dll library provided by
-ANGLE.
+The other method involves using the
+[ANGLE library](https://code.google.com/p/angleproject/). If an OpenGL ES 2.x
+context is requested and no WGL_EXT_create_context_es2_profile extension is
+found, SDL will try to load the libEGL.dll library provided by ANGLE.
+
 To obtain the ANGLE binaries, you can either compile from source from
-https://chromium.googlesource.com/angle/angle or copy the relevant binaries from
-a recent Chrome/Chromium install for Windows. The files you need are:
-    
-    * libEGL.dll
-    * libGLESv2.dll
-    * d3dcompiler_46.dll (supports Windows Vista or later, better shader compiler)
-    or...
-    * d3dcompiler_43.dll (supports Windows XP or later)
-    
+https://chromium.googlesource.com/angle/angle or copy the relevant binaries
+from a recent Chrome/Chromium install for Windows. The files you need are:
+
+- libEGL.dll
+- libGLESv2.dll
+- d3dcompiler_46.dll (supports Windows Vista or later, better shader
+  compiler) *or* d3dcompiler_43.dll (supports Windows XP or later)
+
 If you compile ANGLE from source, you can configure it so it does not need the
-d3dcompiler_* DLL at all (for details on this, see their documentation). 
+d3dcompiler_* DLL at all (for details on this, see their documentation).
 However, by default SDL will try to preload the d3dcompiler_46.dll to
-comply with ANGLE's requirements. If you wish SDL to preload d3dcompiler_43.dll (to
-support Windows XP) or to skip this step at all, you can use the 
-SDL_HINT_VIDEO_WIN_D3DCOMPILER hint (see SDL_hints.h for more details).
+comply with ANGLE's requirements. If you wish SDL to preload
+d3dcompiler_43.dll (to support Windows XP) or to skip this step at all, you
+can use the SDL_HINT_VIDEO_WIN_D3DCOMPILER hint (see SDL_hints.h for more
+details).
 
 Known Bugs:
-    
-    * SDL_GL_SetSwapInterval is currently a no op when using ANGLE. It appears
-      that there's a bug in the library which prevents the window contents from
-      refreshing if this is set to anything other than the default value.
-      
+
+- SDL_GL_SetSwapInterval is currently a no op when using ANGLE. It appears
+  that there's a bug in the library which prevents the window contents from
+  refreshing if this is set to anything other than the default value.
+
+## Vulkan Surface Support
+
+Support for creating Vulkan surfaces is configured on by default. To disable
+it change the value of `SDL_VIDEO_VULKAN` to 0 in `SDL_config_windows.h`. You
+must install the [Vulkan SDK](https://www.lunarg.com/vulkan-sdk/) in order to
+use Vulkan graphics in your application.
+

libs/SDL2/docs/README-winrt.md

@@ -2,56 +2,36 @@ WinRT
 =====
 
 This port allows SDL applications to run on Microsoft's platforms that require
-use of "Windows Runtime", aka. "WinRT", APIs.  WinRT apps are currently
-full-screen only, and run in what Microsoft sometimes refers to as their
-"Modern" (formerly, "Metro"), environment.  For Windows 8.x, Microsoft may also
-refer to them as "Windows Store" apps, due to them being distributed,
-primarily, via a Microsoft-run online store (of the same name).
+use of "Windows Runtime", aka. "WinRT", APIs.  Microsoft may, in some cases,
+refer to them as either "Windows Store", or for Windows 10, "UWP" apps.
 
-Some of the operating systems that include WinRT, are:
-
-* Windows 10, via its Universal Windows Platform (UWP) APIs
-* Windows 8.x
-* Windows RT 8.x (aka. Windows 8.x for ARM processors)
-* Windows Phone 8.x
+In the past, SDL has supported Windows RT 8.x, Windows Phone, etc, but in
+modern times this port is focused on UWP apps, which run on Windows 10,
+and modern Xbox consoles.
 
 
 Requirements
 ------------
 
-* Microsoft Visual C++ (aka Visual Studio), either 2015, 2013, or 2012
+* Microsoft Visual C++ (aka Visual Studio) 2019.
   - Free, "Community" or "Express" editions may be used, so long as they
-    include  support for either "Windows Store" or "Windows Phone" apps.
+    include support for either "Windows Store" or "Windows Phone" apps.
     "Express" versions marked as supporting "Windows Desktop" development
     typically do not include support for creating WinRT apps, to note.
     (The "Community" editions of Visual C++ do, however, support both
     desktop/Win32 and WinRT development).
-  - Visual C++ 2012 can only build apps that target versions 8.0 of Windows,
-    or  Windows Phone.  8.0-targetted apps will run on devices running 8.1
-    editions of Windows, however they will not be able to take advantage of
-    8.1-specific features.
-  - Visual C++ 2013 cannot create app projects that target Windows 8.0.
-    Visual C++ 2013 Update 4, can create app projects for Windows Phone 8.0,
-    Windows Phone 8.1, and Windows 8.1, but not Windows 8.0.  An optional
-    Visual Studio add-in, "Tools for Maintaining Store apps for Windows 8",
-    allows Visual C++ 2013 to load and build Windows 8.0 projects that were
-    created with Visual C++ 2012, so long as Visual C++ 2012 is installed
-    on the same machine.  More details on targeting different versions of
-    Windows can found at the following web pages:
-      - [Develop apps by using Visual Studio 2013](http://msdn.microsoft.com/en-us/library/windows/apps/br211384.aspx)
-      - [To add the Tools for Maintaining Store apps for Windows 8](http://msdn.microsoft.com/en-us/library/windows/apps/dn263114.aspx#AddMaintenanceTools)
 * A valid Microsoft account - This requirement is not imposed by SDL, but
-  rather by Microsoft's Visual C++ toolchain.  This is required to launch or 
+  rather by Microsoft's Visual C++ toolchain.  This is required to launch or
   debug apps.
 
 
 Status
 ------
 
-Here is a rough list of what works, and what doens't:
+Here is a rough list of what works, and what doesn't:
 
 * What works:
-  * compilation via Visual C++ 2012 through 2015
+  * compilation via Visual C++ 2019.
   * compile-time platform detection for SDL programs.  The C/C++ #define,
     `__WINRT__`, will be set to 1 (by SDL) when compiling for WinRT.
   * GPU-accelerated 2D rendering, via SDL_Renderer.
@@ -64,12 +44,18 @@ Here is a rough list of what works, and what doens't:
     SDL_GetPerformanceFrequency(), etc.)
   * file I/O via SDL_RWops
   * mouse input  (unsupported on Windows Phone)
-  * audio, via a modified version of SDL's XAudio2 backend
+  * audio, via SDL's WASAPI backend (if you want to record, your app must
+    have "Microphone" capabilities enabled in its manifest, and the user must
+    not have blocked access. Otherwise, capture devices will fail to work,
+    presenting as a device disconnect shortly after opening it.)
   * .DLL file loading.  Libraries *MUST* be packaged inside applications.  Loading
     anything outside of the app is not supported.
   * system path retrieval via SDL's filesystem APIs
   * game controllers.  Support is provided via the SDL_Joystick and
-    SDL_GameController APIs, and is backed by Microsoft's XInput API.
+    SDL_GameController APIs, and is backed by Microsoft's XInput API.  Please
+    note, however, that Windows limits game-controller support in UWP apps to,
+    "Xbox compatible controllers" (many controllers that work in Win32 apps,
+    do not work in UWP, due to restrictions in UWP itself.)
   * multi-touch input
   * app events.  SDL_APP_WILLENTER* and SDL_APP_DIDENTER* events get sent out as
     appropriate.
@@ -82,7 +68,9 @@ Here is a rough list of what works, and what doens't:
 
 * What partially works:
   * keyboard input.  Most of WinRT's documented virtual keys are supported, as
-    well as many keys with documented hardware scancodes.
+    well as many keys with documented hardware scancodes.  Converting
+    SDL_Scancodes to or from SDL_Keycodes may not work, due to missing APIs
+    (MapVirtualKey()) in Microsoft's Windows Store / UWP APIs.
   * SDLmain.  WinRT uses a different signature for each app's main() function.
     SDL-based apps that use this port must compile in SDL_winrt_main_NonXAML.cpp
     (in `SDL\src\main\winrt\`) directly in order for their C-style main()
@@ -95,8 +83,10 @@ Here is a rough list of what works, and what doens't:
     SDL_CreateSystemCursor() (unsupported on Windows Phone)
   * SDL_WarpMouseInWindow() or SDL_WarpMouseGlobal().  This are not currently
     supported by WinRT itself.
-  * joysticks and game controllers that aren't supported by Microsoft's XInput
-    API.
+  * joysticks and game controllers that either are not supported by
+    Microsoft's XInput API, or are not supported within UWP apps (many
+    controllers that work in Win32, do not work in UWP, due to restrictions in
+    UWP itself).
   * turning off VSync when rendering on Windows Phone.  Attempts to turn VSync
     off on Windows Phone result either in Direct3D not drawing anything, or it
     forcing VSync back on.  As such, SDL_RENDERER_PRESENTVSYNC will always get
@@ -160,7 +150,9 @@ following, at a high-level:
    the linker, and will copy SDL's .dll files to your app's final output.
 4. adjust your app's build settings, at minimum, telling it where to find SDL's
    header files.
-5. add a file that contains a WinRT-appropriate main function.
+5. add files that contains a WinRT-appropriate main function, along with some
+   data to make sure mouse-cursor-hiding (via SDL_ShowCursor(SDL_DISABLE) calls)
+   work properly.
 6. add SDL-specific app code.
 7. build and run your app.
 
@@ -207,7 +199,7 @@ libraries such that, when the app is built:
 
 1. each library gets built for the appropriate CPU architecture(s) and WinRT
    platform(s).
-2. each library's output, such as .dll files, get copied to the app's build 
+2. each library's output, such as .dll files, get copied to the app's build
    output.
 
 To set this up for SDL/WinRT, you'll need to run through the following steps:
@@ -216,13 +208,8 @@ To set this up for SDL/WinRT, you'll need to run through the following steps:
    "Solution Explorer")
 2. right click on your app's solution.
 3. navigate to "Add", then to "Existing Project..."
-4. find SDL/WinRT's Visual C++ project file and open it.  Different project
-   files exist for different WinRT platforms.  All of them are in SDL's
-   source distribution, in the following directories:
-    * `VisualC-WinRT/UWP_VS2015/`        - for Windows 10 / UWP apps
-    * `VisualC-WinRT/WinPhone81_VS2013/` - for Windows Phone 8.1 apps
-    * `VisualC-WinRT/WinRT80_VS2012/`    - for Windows 8.0 apps
-    * `VisualC-WinRT/WinRT81_VS2013/`    - for Windows 8.1 apps
+4. find SDL/WinRT's Visual C++ project file and open it, in the `VisualC-WinRT`
+   directory.
 5. once the project has been added, right-click on your app's project and
    select, "References..."
 6. click on the button titled, "Add New Reference..."
@@ -258,150 +245,155 @@ To change these settings:
 7. edit the "Additional Include Directories" setting, and add a path to SDL's
    "include" directory
 8. **Optional: to enable compilation of C code:** change the setting for
-   "Consume Windows Runtime Extension" from "Yes (/ZW)" to "No".  If you're 
-   working with a completely C++ based project, this step can usually be 
+   "Consume Windows Runtime Extension" from "Yes (/ZW)" to "No".  If you're
+   working with a completely C++ based project, this step can usually be
    omitted.
-9. **Optional: to disable precompiled headers (which can produce 
-   'stdafx.h'-related build errors, if setup incorrectly:** in the left-hand 
-   list, select "Precompiled Headers", then change the setting for "Precompiled 
+9. **Optional: to disable precompiled headers (which can produce
+   'stdafx.h'-related build errors, if setup incorrectly:** in the left-hand
+   list, select "Precompiled Headers", then change the setting for "Precompiled
    Header" from "Use (/Yu)" to "Not Using Precompiled Headers".
 10. close the dialog, saving settings, by clicking the "OK" button
 
 
-### 5. Add a WinRT-appropriate main function to the app. ###
-
-C/C++-based WinRT apps do contain a `main` function that the OS will invoke when 
-the app starts launching. The parameters of WinRT main functions are different 
-than those found on other platforms, Win32 included.  SDL/WinRT provides a 
-platform-appropriate main function that will perform these actions, setup key 
-portions of the app, then invoke a classic, C/C++-style main function (that take 
-in "argc" and "argv" parameters).  The code for this file is contained inside 
-SDL's source distribution, under `src/main/winrt/SDL_winrt_main_NonXAML.cpp`.  
-You'll need to add this file, or a copy of it, to your app's project, and make 
-sure it gets compiled using a Microsoft-specific set of C++ extensions called 
-C++/CX.
+### 5. Add a WinRT-appropriate main function, and a blank-cursor image, to the app. ###
 
-**NOTE: C++/CX compilation is currently required in at least one file of your 
-app's project.  This is to make sure that Visual C++'s linker builds a 'Windows 
-Metadata' file (.winmd) for your app.  Not doing so can lead to build errors.**
+A few files should be included directly in your app's MSVC project, specifically:
+1. a WinRT-appropriate main function (which is different than main() functions on
+   other platforms)
+2. a Win32-style cursor resource, used by SDL_ShowCursor() to hide the mouse cursor
+   (if and when the app needs to do so).  *If this cursor resource is not
+   included, mouse-position reporting may fail if and when the cursor is
+   hidden, due to possible bugs/design-oddities in Windows itself.*
 
-To include `SDL_winrt_main_NonXAML.cpp`:
+To include these files for C/C++ projects:
 
-1. right-click on your project (again, in Visual C++'s Solution Explorer), 
+1. right-click on your project (again, in Visual C++'s Solution Explorer),
    navigate to "Add", then choose "Existing Item...".
-2. open `SDL_winrt_main_NonXAML.cpp`, which is found inside SDL's source 
-   distribution, under `src/main/winrt/`.  Make sure that the open-file dialog 
-   closes, either by double-clicking on the file, or single-clicking on it and 
-   then clicking Add.
-3. right-click on the file (as listed in your project), then click on 
-   "Properties...".
+2. navigate to the directory containing SDL's source code, then into its
+   subdirectory, 'src/main/winrt/'.  Select, then add, the following files:
+   - `SDL_winrt_main_NonXAML.cpp`
+   - `SDL2-WinRTResources.rc`
+   - `SDL2-WinRTResource_BlankCursor.cur`
+3. right-click on the file `SDL_winrt_main_NonXAML.cpp` (as listed in your
+   project), then click on "Properties...".
 4. in the drop-down box next to "Configuration", choose, "All Configurations"
 5. in the drop-down box next to "Platform", choose, "All Platforms"
 6. in the left-hand list, click on "C/C++"
 7. change the setting for "Consume Windows Runtime Extension" to "Yes (/ZW)".
 8. click the OK button.  This will close the dialog.
 
+**NOTE: C++/CX compilation is currently required in at least one file of your
+app's project.  This is to make sure that Visual C++'s linker builds a 'Windows
+Metadata' file (.winmd) for your app.  Not doing so can lead to build errors.**
+
+For non-C++ projects, you will need to call SDL_WinRTRunApp from your language's
+main function, and generate SDL2-WinRTResources.res manually by using `rc` via
+the Developer Command Prompt and including it as a <Win32Resource> within the
+first <PropertyGroup> block in your Visual Studio project file.
 
 ### 6. Add app code and assets ###
 
-At this point, you can add in SDL-specific source code.  Be sure to include a 
-C-style main function (ie: `int main(int argc, char *argv[])`).  From there you 
-should be able to create a single `SDL_Window` (WinRT apps can only have one 
-window, at present), as well as an `SDL_Renderer`.  Direct3D will be used to 
-draw content.  Events are received via SDL's usual event functions 
-(`SDL_PollEvent`, etc.)  If you have a set of existing source files and assets, 
-you can start adding them to the project now.  If not, or if you would like to 
-make sure that you're setup correctly, some short and simple sample code is 
+At this point, you can add in SDL-specific source code.  Be sure to include a
+C-style main function (ie: `int main(int argc, char *argv[])`).  From there you
+should be able to create a single `SDL_Window` (WinRT apps can only have one
+window, at present), as well as an `SDL_Renderer`.  Direct3D will be used to
+draw content.  Events are received via SDL's usual event functions
+(`SDL_PollEvent`, etc.)  If you have a set of existing source files and assets,
+you can start adding them to the project now.  If not, or if you would like to
+make sure that you're setup correctly, some short and simple sample code is
 provided below.
 
 
 #### 6.A. ... when creating a new app ####
 
-If you are creating a new app (rather than porting an existing SDL-based app), 
-or if you would just like a simple app to test SDL/WinRT with before trying to 
-get existing code working, some working SDL/WinRT code is provided below.  To 
+If you are creating a new app (rather than porting an existing SDL-based app),
+or if you would just like a simple app to test SDL/WinRT with before trying to
+get existing code working, some working SDL/WinRT code is provided below.  To
 set this up:
 
 1. right click on your app's project
 2. select Add, then New Item.  An "Add New Item" dialog will show up.
 3. from the left-hand list, choose "Visual C++"
 4. from the middle/main list, choose "C++ File (.cpp)"
-5. near the bottom of the dialog, next to "Name:", type in a name for your 
+5. near the bottom of the dialog, next to "Name:", type in a name for your
 source file, such as, "main.cpp".
-6. click on the Add button.  This will close the dialog, add the new file to 
+6. click on the Add button.  This will close the dialog, add the new file to
 your project, and open the file in Visual C++'s text editor.
 7. Copy and paste the following code into the new file, then save it.
 
+```c
+#include <SDL.h>
+
+int main(int argc, char **argv)
+{
+    SDL_DisplayMode mode;
+    SDL_Window * window = NULL;
+    SDL_Renderer * renderer = NULL;
+    SDL_Event evt;
+    SDL_bool keep_going = SDL_TRUE;
+
+    if (SDL_Init(SDL_INIT_VIDEO) != 0) {
+        return 1;
+    } else if (SDL_GetCurrentDisplayMode(0, &mode) != 0) {
+        return 1;
+    } else if (SDL_CreateWindowAndRenderer(mode.w, mode.h, SDL_WINDOW_FULLSCREEN, &window, &renderer) != 0) {
+        return 1;
+    }
 
-    #include <SDL.h>
-    
-    int main(int argc, char **argv)
-    {
-        SDL_DisplayMode mode;
-        SDL_Window * window = NULL;
-        SDL_Renderer * renderer = NULL;
-        SDL_Event evt;
-    
-        if (SDL_Init(SDL_INIT_VIDEO) != 0) {
-            return 1;
-        }
-    
-        if (SDL_GetCurrentDisplayMode(0, &mode) != 0) {
-            return 1;
-        }
-    
-        if (SDL_CreateWindowAndRenderer(mode.w, mode.h, SDL_WINDOW_FULLSCREEN, &window, &renderer) != 0) {
-            return 1;
-        }
-    
-        while (1) {
-            while (SDL_PollEvent(&evt)) {
+    while (keep_going) {
+        while (SDL_PollEvent(&evt)) {
+            if ((evt.type == SDL_KEYDOWN) && (evt.key.keysym.sym == SDLK_ESCAPE)) {
+                keep_going = SDL_FALSE;
             }
-    
-            SDL_SetRenderDrawColor(renderer, 0, 255, 0, 255);
-            SDL_RenderClear(renderer);
-            SDL_RenderPresent(renderer);
         }
+
+        SDL_SetRenderDrawColor(renderer, 0, 255, 0, 255);
+        SDL_RenderClear(renderer);
+        SDL_RenderPresent(renderer);
     }
 
+    SDL_Quit();
+    return 0;
+}
+```
 
 #### 6.B. Adding code and assets ####
 
-If you have existing code and assets that you'd like to add, you should be able 
+If you have existing code and assets that you'd like to add, you should be able
 to add them now.  The process for adding a set of files is as such.
 
 1. right click on the app's project
 2. select Add, then click on "New Item..."
-3. open any source, header, or asset files as appropriate.  Support for C and 
+3. open any source, header, or asset files as appropriate.  Support for C and
 C++ is available.
 
-Do note that WinRT only supports a subset of the APIs that are available to 
-Win32-based apps.  Many portions of the Win32 API and the C runtime are not 
+Do note that WinRT only supports a subset of the APIs that are available to
+Win32-based apps.  Many portions of the Win32 API and the C runtime are not
 available.
 
-A list of unsupported C APIs can be found at 
+A list of unsupported C APIs can be found at
 <http://msdn.microsoft.com/en-us/library/windows/apps/jj606124.aspx>
 
-General information on using the C runtime in WinRT can be found at 
+General information on using the C runtime in WinRT can be found at
 <https://msdn.microsoft.com/en-us/library/hh972425.aspx>
 
-A list of supported Win32 APIs for WinRT apps can be found at 
-<http://msdn.microsoft.com/en-us/library/windows/apps/br205757.aspx>.  To note, 
-the list of supported Win32 APIs for Windows Phone 8.0 is different.  
-That list can be found at 
+A list of supported Win32 APIs for WinRT apps can be found at
+<http://msdn.microsoft.com/en-us/library/windows/apps/br205757.aspx>.  To note,
+the list of supported Win32 APIs for Windows Phone 8.0 is different.
+That list can be found at
 <http://msdn.microsoft.com/en-us/library/windowsphone/develop/jj662956(v=vs.105).aspx>
 
 
 ### 7. Build and run your app ###
 
-Your app project should now be setup, and you should be ready to build your app.  
-To run it on the local machine, open the Debug menu and choose "Start 
-Debugging".  This will build your app, then run your app full-screen.  To switch 
-out of your app, press the Windows key.  Alternatively, you can choose to run 
-your app in a window.  To do this, before building and running your app, find 
-the drop-down menu in Visual C++'s toolbar that says, "Local Machine".  Expand 
-this by clicking on the arrow on the right side of the list, then click on 
-Simulator.  Once you do that, any time you build and run the app, the app will 
+Your app project should now be setup, and you should be ready to build your app.
+To run it on the local machine, open the Debug menu and choose "Start
+Debugging".  This will build your app, then run your app full-screen.  To switch
+out of your app, press the Windows key.  Alternatively, you can choose to run
+your app in a window.  To do this, before building and running your app, find
+the drop-down menu in Visual C++'s toolbar that says, "Local Machine".  Expand
+this by clicking on the arrow on the right side of the list, then click on
+Simulator.  Once you do that, any time you build and run the app, the app will
 launch in window, rather than full-screen.
 
 
@@ -414,37 +406,37 @@ Windows 8.x that ran primarily on ARM-based tablet computers.
 
 To build and run the app on ARM-based, "Windows RT" devices, you'll need to:
 
-- install Microsoft's "Remote Debugger" on the device.  Visual C++ installs and 
+- install Microsoft's "Remote Debugger" on the device.  Visual C++ installs and
   debugs ARM-based apps via IP networks.
-- change a few options on the development machine, both to make sure it builds 
-  for ARM (rather than x86 or x64), and to make sure it knows how to find the 
+- change a few options on the development machine, both to make sure it builds
+  for ARM (rather than x86 or x64), and to make sure it knows how to find the
   Windows RT device (on the network).
 
-Microsoft's Remote Debugger can be found at 
-<https://msdn.microsoft.com/en-us/library/hh441469.aspx>.  Please note 
-that separate versions of this debugger exist for different versions of Visual 
+Microsoft's Remote Debugger can be found at
+<https://msdn.microsoft.com/en-us/library/hh441469.aspx>.  Please note
+that separate versions of this debugger exist for different versions of Visual
 C++, one each for MSVC 2015, 2013, and 2012.
 
 To setup Visual C++ to launch your app on an ARM device:
 
-1. make sure the Remote Debugger is running on your ARM device, and that it's on 
+1. make sure the Remote Debugger is running on your ARM device, and that it's on
    the same IP network as your development machine.
-2. from Visual C++'s toolbar, find a drop-down menu that says, "Win32".  Click 
+2. from Visual C++'s toolbar, find a drop-down menu that says, "Win32".  Click
    it, then change the value to "ARM".
-3. make sure Visual C++ knows the hostname or IP address of the ARM device.  To 
+3. make sure Visual C++ knows the hostname or IP address of the ARM device.  To
    do this:
     1. open the app project's properties
     2. select "Debugging"
-    3. next to "Machine Name", enter the hostname or IP address of the ARM 
+    3. next to "Machine Name", enter the hostname or IP address of the ARM
        device
     4. if, and only if, you've turned off authentication in the Remote Debugger,
        then change the setting for "Require Authentication" to No
     5. click "OK"
-4. build and run the app (from Visual C++).  The first time you do this, a 
-   prompt will show up on the ARM device, asking for a Microsoft Account.  You 
-   do, unfortunately, need to log in here, and will need to follow the 
-   subsequent registration steps in order to launch the app.  After you do so, 
-   if the app didn't already launch, try relaunching it again from within Visual 
+4. build and run the app (from Visual C++).  The first time you do this, a
+   prompt will show up on the ARM device, asking for a Microsoft Account.  You
+   do, unfortunately, need to log in here, and will need to follow the
+   subsequent registration steps in order to launch the app.  After you do so,
+   if the app didn't already launch, try relaunching it again from within Visual
    C++.
 
 
@@ -466,3 +458,62 @@ section.
 
     /nodefaultlib:vccorlibd /nodefaultlib:msvcrtd vccorlibd.lib msvcrtd.lib
 
+
+#### Mouse-motion events fail to get sent, or SDL_GetMouseState() fails to return updated values
+
+This may be caused by a bug in Windows itself, whereby hiding the mouse
+cursor can cause mouse-position reporting to fail.
+
+SDL provides a workaround for this, but it requires that an app links to a
+set of Win32-style cursor image-resource files.  A copy of suitable resource
+files can be found in `src/main/winrt/`.  Adding them to an app's Visual C++
+project file should be sufficient to get the app to use them.
+
+
+#### SDL's Visual Studio project file fails to open, with message, "The system can't find the file specified."
+
+This can be caused for any one of a few reasons, which Visual Studio can
+report, but won't always do so in an up-front manner.
+
+To help determine why this error comes up:
+
+1. open a copy of Visual Studio without opening a project file.  This can be
+   accomplished via Windows' Start Menu, among other means.
+2. show Visual Studio's Output window.  This can be done by going to VS'
+   menu bar, then to View, and then to Output.
+3. try opening the SDL project file directly by going to VS' menu bar, then
+   to File, then to Open, then to Project/Solution.  When a File-Open dialog
+   appears, open the SDL project (such as the one in SDL's source code, in its
+   directory, VisualC-WinRT/UWP_VS2015/).
+4. after attempting to open SDL's Visual Studio project file, additional error
+   information will be output to the Output window.
+
+If Visual Studio reports (via its Output window) that the project:
+
+"could not be loaded because it's missing install components. To fix this launch Visual Studio setup with the following selections:
+Microsoft.VisualStudio.ComponentGroup.UWP.VC"
+
+... then you will need to re-launch Visual Studio's installer, and make sure that
+the workflow for "Universal Windows Platform development" is checked, and that its
+optional component, "C++ Universal Windows Platform tools" is also checked.  While
+you are there, if you are planning on targeting UWP / Windows 10, also make sure
+that you check the optional component, "Windows 10 SDK (10.0.10240.0)".  After
+making sure these items are checked as-appropriate, install them.
+
+Once you install these components, try re-launching Visual Studio, and re-opening
+the SDL project file.  If you still get the error dialog, try using the Output
+window, again, seeing what Visual Studio says about it.
+
+
+#### Game controllers / joysticks aren't working!
+
+Windows only permits certain game controllers and joysticks to work within
+WinRT / UWP apps.  Even if a game controller or joystick works in a Win32
+app, that device is not guaranteed to work inside a WinRT / UWP app.
+
+According to Microsoft, "Xbox compatible controllers" should work inside
+UWP apps, potentially with more working in the future.  This includes, but
+may not be limited to, Microsoft-made Xbox controllers and USB adapters.
+(Source: https://social.msdn.microsoft.com/Forums/en-US/9064838b-e8c3-4c18-8a83-19bf0dfe150d/xinput-fails-to-detect-game-controllers?forum=wpdevelop)
+
+

libs/SDL2/docs/README.md

-Simple DirectMedia Layer {#mainpage}
-========================
+# Simple DirectMedia Layer
 
-                                  (SDL)
-
-                                Version 2.0
-
----
-http://www.libsdl.org/
+https://www.libsdl.org/
 
 Simple DirectMedia Layer is a cross-platform development library designed
 to provide low level access to audio, keyboard, mouse, joystick, and graphics
@@ -14,14 +8,14 @@ hardware via OpenGL and Direct3D. It is used by video playback software,
 emulators, and popular games including Valve's award winning catalog
 and many Humble Bundle games.
 
-SDL officially supports Windows, Mac OS X, Linux, iOS, and Android.
+SDL officially supports Windows, macOS, Linux, iOS, and Android.
 Support for other platforms may be found in the source code.
 
 SDL is written in C, works natively with C++, and there are bindings 
 available for several other languages, including C# and Python.
 
 This library is distributed under the zlib license, which can be found
-in the file "COPYING.txt".
+in the file "LICENSE.txt".
 
 The best way to learn how to use SDL is to check out the header files in
 the "include" subdirectory and the programs in the "test" subdirectory.
@@ -34,30 +28,36 @@ More documentation and FAQs are available online at [the wiki](http://wiki.libsd
 - [DirectFB](README-directfb.md)
 - [DynAPI](README-dynapi.md)
 - [Emscripten](README-emscripten.md)
+- [GDK](README-gdk.md)
 - [Gesture](README-gesture.md)
-- [Mercurial](README-hg.md)
+- [Git](README-git.md)
 - [iOS](README-ios.md)
 - [Linux](README-linux.md)
-- [OS X](README-macosx.md)
+- [macOS](README-macos.md)
+- [OS/2](README-os2.md)
 - [Native Client](README-nacl.md)
 - [Pandora](README-pandora.md)
 - [Supported Platforms](README-platforms.md)
 - [Porting information](README-porting.md)
 - [PSP](README-psp.md)
+- [PS2](README-ps2.md)
 - [Raspberry Pi](README-raspberrypi.md)
 - [Touch](README-touch.md)
+- [Versions](README-versions.md)
 - [WinCE](README-wince.md)
 - [Windows](README-windows.md)
 - [WinRT](README-winrt.md)
+- [PSVita](README-vita.md)
+- [Nokia N-Gage](README-ngage.md)
 
 If you need help with the library, or just want to discuss SDL related
-issues, you can join the [developers mailing list](http://www.libsdl.org/mailing-list.php)
+issues, you can join the [SDL Discourse](https://discourse.libsdl.org/),
+which can be used as a web forum or a mailing list, at your preference.
 
 If you want to report bugs or contribute patches, please submit them to
-[bugzilla](http://bugzilla.libsdl.org/)
+[our bug tracker](https://github.com/libsdl-org/SDL/issues)
 
 Enjoy!
 
 
 Sam Lantinga <mailto:slouken@libsdl.org>
-

libs/SDL2/docs/doxyfile

@@ -640,6 +640,7 @@ EXCLUDE                = ../include/SDL_opengles2_gl2ext.h \
                          ../include/SDL_opengles.h \
                          ../include/SDL_opengl.h \
                          ../include/SDL_egl.h \
+                         ./release_checklist.md \
 
 
 # The EXCLUDE_SYMLINKS tag can be used select whether or not files or 

libs/SDL2/docs/release_checklist.md

+# Release checklist
+
+When changing the version, run `build-scripts/update-version.sh X Y Z`,
+where `X Y Z` are the major version, minor version, and patch level. So
+`2 28 1` means "change the version to 2.28.1". This script does much of the
+mechanical work.
+
+
+## New feature release
+
+* Update `WhatsNew.txt`
+
+* Bump version number to 2.EVEN.0:
+
+    * `./build-scripts/update-version.sh 2 EVEN 0`
+
+* Do the release
+
+* Update the website file include/header.inc.php to reflect the new version
+
+## New bugfix release
+
+* Check that no new API/ABI was added
+
+    * If it was, do a new feature release (see above) instead
+
+* Bump version number from 2.Y.Z to 2.Y.(Z+1) (Y is even)
+
+    * `./build-scripts/update-version.sh 2 Y Z+1`
+
+* Do the release
+
+* Update the website file include/header.inc.php to reflect the new version
+
+## After a feature release
+
+* Create a branch like `release-2.24.x`
+
+* Bump version number to 2.ODD.0 for next development branch
+
+    * `./build-scripts/update-version.sh 2 ODD 0`
+
+## New development prerelease
+
+* Bump version number from 2.Y.Z to 2.Y.(Z+1) (Y is odd)
+
+    * `./build-scripts/update-version.sh 2 Y Z+1`
+
+* Do the release

libs/SDL2/i686-w64-mingw32/bin/sdl2-config

 #!/bin/sh
 
-prefix=/usr/local/cross-tools/i686-w64-mingw32
+# Get the canonical path of the folder containing this script
+bindir=$(cd -P -- "$(dirname -- "$0")" && printf '%s\n' "$(pwd -P)")
+
+# Calculate the canonical path of the prefix, relative to the folder of this script
+prefix=$(cd -P -- "$bindir/.." && printf '%s\n' "$(pwd -P)")
 exec_prefix=${prefix}
 exec_prefix_set=no
 libdir=${exec_prefix}/lib
@@ -39,17 +43,18 @@ while test $# -gt 0; do
       echo $exec_prefix
       ;;
     --version)
-      echo 2.0.4
+      echo 2.28.5
       ;;
     --cflags)
       echo -I${prefix}/include/SDL2  -Dmain=SDL_main
       ;;
     --libs)
-      echo -L${exec_prefix}/lib  -lmingw32 -lSDL2main -lSDL2  -mwindows
+      echo -L${exec_prefix}/lib  -lmingw32 -lSDL2main -lSDL2 -mwindows
       ;;
     --static-libs)
 #    --libs|--static-libs)
-      echo -L${exec_prefix}/lib  -lmingw32 -lSDL2main -lSDL2  -mwindows  -Wl,--no-undefined -lm -ldinput8 -ldxguid -ldxerr8 -luser32 -lgdi32 -lwinmm -limm32 -lole32 -loleaut32 -lshell32 -lversion -luuid -static-libgcc
+      sdl_static_libs=$(echo "-lmingw32 -lSDL2main -lSDL2 -mwindows  -Wl,--dynamicbase -Wl,--nxcompat -lm -ldinput8 -ldxguid -ldxerr8 -luser32 -lgdi32 -lwinmm -limm32 -lole32 -loleaut32 -lshell32 -lsetupapi -lversion -luuid" | sed -E "s#-lSDL2[ $]#$libdir/libSDL2.a #g")
+      echo -L${exec_prefix}/lib $sdl_static_libs
       ;;
     *)
       echo "${usage}" 1>&2

libs/SDL2/i686-w64-mingw32/include/SDL2/SDL.h

 /*
   Simple DirectMedia Layer
-  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+  Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>
 
   This software is provided 'as-is', without any express or implied
   warranty.  In no event will the authors be held liable for any damages
@@ -26,8 +26,8 @@
  */
 
 
-#ifndef _SDL_H
-#define _SDL_H
+#ifndef SDL_h_
+#define SDL_h_
 
 #include "SDL_main.h"
 #include "SDL_stdinc.h"
@@ -40,22 +40,29 @@
 #include "SDL_error.h"
 #include "SDL_events.h"
 #include "SDL_filesystem.h"
-#include "SDL_joystick.h"
 #include "SDL_gamecontroller.h"
+#include "SDL_guid.h"
 #include "SDL_haptic.h"
+#include "SDL_hidapi.h"
 #include "SDL_hints.h"
+#include "SDL_joystick.h"
 #include "SDL_loadso.h"
 #include "SDL_log.h"
 #include "SDL_messagebox.h"
+#include "SDL_metal.h"
 #include "SDL_mutex.h"
 #include "SDL_power.h"
 #include "SDL_render.h"
 #include "SDL_rwops.h"
+#include "SDL_sensor.h"
+#include "SDL_shape.h"
 #include "SDL_system.h"
 #include "SDL_thread.h"
 #include "SDL_timer.h"
 #include "SDL_version.h"
 #include "SDL_video.h"
+#include "SDL_locale.h"
+#include "SDL_misc.h"
 
 #include "begin_code.h"
 /* Set up for C function definitions, even when using C++ */
@@ -72,52 +79,146 @@ extern "C" {
  *  specify the subsystems which you will be using in your application.
  */
 /* @{ */
-#define SDL_INIT_TIMER          0x00000001
-#define SDL_INIT_AUDIO          0x00000010
-#define SDL_INIT_VIDEO          0x00000020  /**< SDL_INIT_VIDEO implies SDL_INIT_EVENTS */
-#define SDL_INIT_JOYSTICK       0x00000200  /**< SDL_INIT_JOYSTICK implies SDL_INIT_EVENTS */
-#define SDL_INIT_HAPTIC         0x00001000
-#define SDL_INIT_GAMECONTROLLER 0x00002000  /**< SDL_INIT_GAMECONTROLLER implies SDL_INIT_JOYSTICK */
-#define SDL_INIT_EVENTS         0x00004000
-#define SDL_INIT_NOPARACHUTE    0x00100000  /**< compatibility; this flag is ignored. */
+#define SDL_INIT_TIMER          0x00000001u
+#define SDL_INIT_AUDIO          0x00000010u
+#define SDL_INIT_VIDEO          0x00000020u  /**< SDL_INIT_VIDEO implies SDL_INIT_EVENTS */
+#define SDL_INIT_JOYSTICK       0x00000200u  /**< SDL_INIT_JOYSTICK implies SDL_INIT_EVENTS */
+#define SDL_INIT_HAPTIC         0x00001000u
+#define SDL_INIT_GAMECONTROLLER 0x00002000u  /**< SDL_INIT_GAMECONTROLLER implies SDL_INIT_JOYSTICK */
+#define SDL_INIT_EVENTS         0x00004000u
+#define SDL_INIT_SENSOR         0x00008000u
+#define SDL_INIT_NOPARACHUTE    0x00100000u  /**< compatibility; this flag is ignored. */
 #define SDL_INIT_EVERYTHING ( \
                 SDL_INIT_TIMER | SDL_INIT_AUDIO | SDL_INIT_VIDEO | SDL_INIT_EVENTS | \
-                SDL_INIT_JOYSTICK | SDL_INIT_HAPTIC | SDL_INIT_GAMECONTROLLER \
+                SDL_INIT_JOYSTICK | SDL_INIT_HAPTIC | SDL_INIT_GAMECONTROLLER | SDL_INIT_SENSOR \
             )
 /* @} */
 
 /**
- *  This function initializes  the subsystems specified by \c flags
+ * Initialize the SDL library.
+ *
+ * SDL_Init() simply forwards to calling SDL_InitSubSystem(). Therefore, the
+ * two may be used interchangeably. Though for readability of your code
+ * SDL_InitSubSystem() might be preferred.
+ *
+ * The file I/O (for example: SDL_RWFromFile) and threading (SDL_CreateThread)
+ * subsystems are initialized by default. Message boxes
+ * (SDL_ShowSimpleMessageBox) also attempt to work without initializing the
+ * video subsystem, in hopes of being useful in showing an error dialog when
+ * SDL_Init fails. You must specifically initialize other subsystems if you
+ * use them in your application.
+ *
+ * Logging (such as SDL_Log) works without initialization, too.
+ *
+ * `flags` may be any of the following OR'd together:
+ *
+ * - `SDL_INIT_TIMER`: timer subsystem
+ * - `SDL_INIT_AUDIO`: audio subsystem
+ * - `SDL_INIT_VIDEO`: video subsystem; automatically initializes the events
+ *   subsystem
+ * - `SDL_INIT_JOYSTICK`: joystick subsystem; automatically initializes the
+ *   events subsystem
+ * - `SDL_INIT_HAPTIC`: haptic (force feedback) subsystem
+ * - `SDL_INIT_GAMECONTROLLER`: controller subsystem; automatically
+ *   initializes the joystick subsystem
+ * - `SDL_INIT_EVENTS`: events subsystem
+ * - `SDL_INIT_EVERYTHING`: all of the above subsystems
+ * - `SDL_INIT_NOPARACHUTE`: compatibility; this flag is ignored
+ *
+ * Subsystem initialization is ref-counted, you must call SDL_QuitSubSystem()
+ * for each SDL_InitSubSystem() to correctly shutdown a subsystem manually (or
+ * call SDL_Quit() to force shutdown). If a subsystem is already loaded then
+ * this call will increase the ref-count and return.
+ *
+ * \param flags subsystem initialization flags
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_InitSubSystem
+ * \sa SDL_Quit
+ * \sa SDL_SetMainReady
+ * \sa SDL_WasInit
  */
 extern DECLSPEC int SDLCALL SDL_Init(Uint32 flags);
 
 /**
- *  This function initializes specific SDL subsystems
+ * Compatibility function to initialize the SDL library.
+ *
+ * In SDL2, this function and SDL_Init() are interchangeable.
+ *
+ * \param flags any of the flags used by SDL_Init(); see SDL_Init for details.
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
+ *
+ * \since This function is available since SDL 2.0.0.
  *
- *  Subsystem initialization is ref-counted, you must call
- *  SDL_QuitSubSystem for each SDL_InitSubSystem to correctly
- *  shutdown a subsystem manually (or call SDL_Quit to force shutdown).
- *  If a subsystem is already loaded then this call will
- *  increase the ref-count and return.
+ * \sa SDL_Init
+ * \sa SDL_Quit
+ * \sa SDL_QuitSubSystem
  */
 extern DECLSPEC int SDLCALL SDL_InitSubSystem(Uint32 flags);
 
 /**
- *  This function cleans up specific SDL subsystems
+ * Shut down specific SDL subsystems.
+ *
+ * If you start a subsystem using a call to that subsystem's init function
+ * (for example SDL_VideoInit()) instead of SDL_Init() or SDL_InitSubSystem(),
+ * SDL_QuitSubSystem() and SDL_WasInit() will not work. You will need to use
+ * that subsystem's quit function (SDL_VideoQuit()) directly instead. But
+ * generally, you should not be using those functions directly anyhow; use
+ * SDL_Init() instead.
+ *
+ * You still need to call SDL_Quit() even if you close all open subsystems
+ * with SDL_QuitSubSystem().
+ *
+ * \param flags any of the flags used by SDL_Init(); see SDL_Init for details.
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_InitSubSystem
+ * \sa SDL_Quit
  */
 extern DECLSPEC void SDLCALL SDL_QuitSubSystem(Uint32 flags);
 
 /**
- *  This function returns a mask of the specified subsystems which have
- *  previously been initialized.
+ * Get a mask of the specified subsystems which are currently initialized.
+ *
+ * \param flags any of the flags used by SDL_Init(); see SDL_Init for details.
+ * \returns a mask of all initialized subsystems if `flags` is 0, otherwise it
+ *          returns the initialization status of the specified subsystems.
+ *
+ *          The return value does not include SDL_INIT_NOPARACHUTE.
  *
- *  If \c flags is 0, it returns a mask of all initialized subsystems.
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_Init
+ * \sa SDL_InitSubSystem
  */
 extern DECLSPEC Uint32 SDLCALL SDL_WasInit(Uint32 flags);
 
 /**
- *  This function cleans up all initialized subsystems. You should
- *  call it upon all exit conditions.
+ * Clean up all initialized subsystems.
+ *
+ * You should call this function even if you have already shutdown each
+ * initialized subsystem with SDL_QuitSubSystem(). It is safe to call this
+ * function even in the case of errors in initialization.
+ *
+ * If you start a subsystem using a call to that subsystem's init function
+ * (for example SDL_VideoInit()) instead of SDL_Init() or SDL_InitSubSystem(),
+ * then you must use that subsystem's quit function (SDL_VideoQuit()) to shut
+ * it down before calling SDL_Quit(). But generally, you should not be using
+ * those functions directly anyhow; use SDL_Init() instead.
+ *
+ * You can use this function with atexit() to ensure that it is run when your
+ * application is shutdown, but it is not wise to do this from a library or
+ * other dynamically loaded code.
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_Init
+ * \sa SDL_QuitSubSystem
  */
 extern DECLSPEC void SDLCALL SDL_Quit(void);
 
@@ -127,6 +228,6 @@ extern DECLSPEC void SDLCALL SDL_Quit(void);
 #endif
 #include "close_code.h"
 
-#endif /* _SDL_H */
+#endif /* SDL_h_ */
 
 /* vi: set ts=4 sw=4 expandtab: */

libs/SDL2/i686-w64-mingw32/include/SDL2/SDL_assert.h

 /*
   Simple DirectMedia Layer
-  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+  Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>
 
   This software is provided 'as-is', without any express or implied
   warranty.  In no event will the authors be held liable for any damages
@@ -19,10 +19,10 @@
   3. This notice may not be removed or altered from any source distribution.
 */
 
-#ifndef _SDL_assert_h
-#define _SDL_assert_h
+#ifndef SDL_assert_h_
+#define SDL_assert_h_
 
-#include "SDL_config.h"
+#include "SDL_stdinc.h"
 
 #include "begin_code.h"
 /* Set up for C function definitions, even when using C++ */
@@ -51,9 +51,19 @@ assert can have unique static variables associated with it.
 /* Don't include intrin.h here because it contains C++ code */
     extern void __cdecl __debugbreak(void);
     #define SDL_TriggerBreakpoint() __debugbreak()
-#elif (!defined(__NACL__) && defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)))
+#elif _SDL_HAS_BUILTIN(__builtin_debugtrap)
+    #define SDL_TriggerBreakpoint() __builtin_debugtrap()
+#elif ( (!defined(__NACL__)) && ((defined(__GNUC__) || defined(__clang__)) && (defined(__i386__) || defined(__x86_64__))) )
     #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "int $3\n\t" )
-#elif defined(HAVE_SIGNAL_H)
+#elif (defined(__GNUC__) || defined(__clang__)) && defined(__riscv)
+    #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "ebreak\n\t" )
+#elif ( defined(__APPLE__) && (defined(__arm64__) || defined(__aarch64__)) )  /* this might work on other ARM targets, but this is a known quantity... */
+    #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "brk #22\n\t" )
+#elif defined(__APPLE__) && defined(__arm__)
+    #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "bkpt #22\n\t" )
+#elif defined(__386__) && defined(__WATCOMC__)
+    #define SDL_TriggerBreakpoint() { _asm { int 0x03 } }
+#elif defined(HAVE_SIGNAL_H) && !defined(__WATCOMC__)
     #include <signal.h>
     #define SDL_TriggerBreakpoint() raise(SIGTRAP)
 #else
@@ -63,7 +73,7 @@ assert can have unique static variables associated with it.
 
 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 supports __func__ as a standard. */
 #   define SDL_FUNCTION __func__
-#elif ((__GNUC__ >= 2) || defined(_MSC_VER))
+#elif ((defined(__GNUC__) && (__GNUC__ >= 2)) || defined(_MSC_VER) || defined (__WATCOMC__))
 #   define SDL_FUNCTION __FUNCTION__
 #else
 #   define SDL_FUNCTION "???"
@@ -117,12 +127,10 @@ typedef struct SDL_AssertData
     const struct SDL_AssertData *next;
 } SDL_AssertData;
 
-#if (SDL_ASSERT_LEVEL > 0)
-
 /* Never call this directly. Use the SDL_assert* macros. */
 extern DECLSPEC SDL_AssertState SDLCALL SDL_ReportAssertion(SDL_AssertData *,
-                                                             const char *,
-                                                             const char *, int)
+                                                            const char *,
+                                                            const char *, int)
 #if defined(__clang__)
 #if __has_feature(attribute_analyzer_noreturn)
 /* this tells Clang's static analysis that we're a custom assert function,
@@ -143,9 +151,7 @@ extern DECLSPEC SDL_AssertState SDLCALL SDL_ReportAssertion(SDL_AssertData *,
 #define SDL_enabled_assert(condition) \
     do { \
         while ( !(condition) ) { \
-            static struct SDL_AssertData sdl_assert_data = { \
-                0, 0, #condition, 0, 0, 0, 0 \
-            }; \
+            static struct SDL_AssertData sdl_assert_data = { 0, 0, #condition, 0, 0, 0, 0 }; \
             const SDL_AssertState sdl_assert_state = SDL_ReportAssertion(&sdl_assert_data, SDL_FUNCTION, SDL_FILE, SDL_LINE); \
             if (sdl_assert_state == SDL_ASSERTION_RETRY) { \
                 continue; /* go again. */ \
@@ -156,8 +162,6 @@ extern DECLSPEC SDL_AssertState SDLCALL SDL_ReportAssertion(SDL_AssertData *,
         } \
     } while (SDL_NULL_WHILE_LOOP_CONDITION)
 
-#endif  /* enabled assertions support code */
-
 /* Enable various levels of assertions. */
 #if SDL_ASSERT_LEVEL == 0   /* assertions disabled */
 #   define SDL_assert(condition) SDL_disabled_assert(condition)
@@ -183,92 +187,121 @@ extern DECLSPEC SDL_AssertState SDLCALL SDL_ReportAssertion(SDL_AssertData *,
 #define SDL_assert_always(condition) SDL_enabled_assert(condition)
 
 
+/**
+ * A callback that fires when an SDL assertion fails.
+ *
+ * \param data a pointer to the SDL_AssertData structure corresponding to the
+ *             current assertion
+ * \param userdata what was passed as `userdata` to SDL_SetAssertionHandler()
+ * \returns an SDL_AssertState value indicating how to handle the failure.
+ */
 typedef SDL_AssertState (SDLCALL *SDL_AssertionHandler)(
                                  const SDL_AssertData* data, void* userdata);
 
 /**
- *  \brief Set an application-defined assertion handler.
+ * Set an application-defined assertion handler.
  *
- *  This allows an app to show its own assertion UI and/or force the
- *  response to an assertion failure. If the app doesn't provide this, SDL
- *  will try to do the right thing, popping up a system-specific GUI dialog,
- *  and probably minimizing any fullscreen windows.
+ * This function allows an application to show its own assertion UI and/or
+ * force the response to an assertion failure. If the application doesn't
+ * provide this, SDL will try to do the right thing, popping up a
+ * system-specific GUI dialog, and probably minimizing any fullscreen windows.
  *
- *  This callback may fire from any thread, but it runs wrapped in a mutex, so
- *  it will only fire from one thread at a time.
+ * This callback may fire from any thread, but it runs wrapped in a mutex, so
+ * it will only fire from one thread at a time.
  *
- *  Setting the callback to NULL restores SDL's original internal handler.
+ * This callback is NOT reset to SDL's internal handler upon SDL_Quit()!
  *
- *  This callback is NOT reset to SDL's internal handler upon SDL_Quit()!
+ * \param handler the SDL_AssertionHandler function to call when an assertion
+ *                fails or NULL for the default handler
+ * \param userdata a pointer that is passed to `handler`
  *
- *  \return SDL_AssertState value of how to handle the assertion failure.
+ * \since This function is available since SDL 2.0.0.
  *
- *  \param handler Callback function, called when an assertion fails.
- *  \param userdata A pointer passed to the callback as-is.
+ * \sa SDL_GetAssertionHandler
  */
 extern DECLSPEC void SDLCALL SDL_SetAssertionHandler(
                                             SDL_AssertionHandler handler,
                                             void *userdata);
 
 /**
- *  \brief Get the default assertion handler.
+ * Get the default assertion handler.
+ *
+ * This returns the function pointer that is called by default when an
+ * assertion is triggered. This is an internal function provided by SDL, that
+ * is used for assertions when SDL_SetAssertionHandler() hasn't been used to
+ * provide a different function.
+ *
+ * \returns the default SDL_AssertionHandler that is called when an assert
+ *          triggers.
  *
- *  This returns the function pointer that is called by default when an
- *   assertion is triggered. This is an internal function provided by SDL,
- *   that is used for assertions when SDL_SetAssertionHandler() hasn't been
- *   used to provide a different function.
+ * \since This function is available since SDL 2.0.2.
  *
- *  \return The default SDL_AssertionHandler that is called when an assert triggers.
+ * \sa SDL_GetAssertionHandler
  */
 extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetDefaultAssertionHandler(void);
 
 /**
- *  \brief Get the current assertion handler.
+ * Get the current assertion handler.
  *
- *  This returns the function pointer that is called when an assertion is
- *   triggered. This is either the value last passed to
- *   SDL_SetAssertionHandler(), or if no application-specified function is
- *   set, is equivalent to calling SDL_GetDefaultAssertionHandler().
+ * This returns the function pointer that is called when an assertion is
+ * triggered. This is either the value last passed to
+ * SDL_SetAssertionHandler(), or if no application-specified function is set,
+ * is equivalent to calling SDL_GetDefaultAssertionHandler().
  *
- *   \param puserdata Pointer to a void*, which will store the "userdata"
- *                    pointer that was passed to SDL_SetAssertionHandler().
- *                    This value will always be NULL for the default handler.
- *                    If you don't care about this data, it is safe to pass
- *                    a NULL pointer to this function to ignore it.
- *  \return The SDL_AssertionHandler that is called when an assert triggers.
+ * The parameter `puserdata` is a pointer to a void*, which will store the
+ * "userdata" pointer that was passed to SDL_SetAssertionHandler(). This value
+ * will always be NULL for the default handler. If you don't care about this
+ * data, it is safe to pass a NULL pointer to this function to ignore it.
+ *
+ * \param puserdata pointer which is filled with the "userdata" pointer that
+ *                  was passed to SDL_SetAssertionHandler()
+ * \returns the SDL_AssertionHandler that is called when an assert triggers.
+ *
+ * \since This function is available since SDL 2.0.2.
+ *
+ * \sa SDL_SetAssertionHandler
  */
 extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetAssertionHandler(void **puserdata);
 
 /**
- *  \brief Get a list of all assertion failures.
+ * Get a list of all assertion failures.
  *
- *  Get all assertions triggered since last call to SDL_ResetAssertionReport(),
- *  or the start of the program.
+ * This function gets all assertions triggered since the last call to
+ * SDL_ResetAssertionReport(), or the start of the program.
  *
- *  The proper way to examine this data looks something like this:
+ * The proper way to examine this data looks something like this:
  *
- *  <code>
- *  const SDL_AssertData *item = SDL_GetAssertionReport();
- *  while (item) {
- *      printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\n",
- *             item->condition, item->function, item->filename,
- *             item->linenum, item->trigger_count,
- *             item->always_ignore ? "yes" : "no");
- *      item = item->next;
- *  }
- *  </code>
+ * ```c
+ * const SDL_AssertData *item = SDL_GetAssertionReport();
+ * while (item) {
+ *    printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\\n",
+ *           item->condition, item->function, item->filename,
+ *           item->linenum, item->trigger_count,
+ *           item->always_ignore ? "yes" : "no");
+ *    item = item->next;
+ * }
+ * ```
  *
- *  \return List of all assertions.
- *  \sa SDL_ResetAssertionReport
+ * \returns a list of all failed assertions or NULL if the list is empty. This
+ *          memory should not be modified or freed by the application.
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_ResetAssertionReport
  */
 extern DECLSPEC const SDL_AssertData * SDLCALL SDL_GetAssertionReport(void);
 
 /**
- *  \brief Reset the list of all assertion failures.
+ * Clear the list of all assertion failures.
+ *
+ * This function will clear the list of all assertions triggered up to that
+ * point. Immediately following this call, SDL_GetAssertionReport will return
+ * no items. In addition, any previously-triggered assertions will be reset to
+ * a trigger_count of zero, and their always_ignore state will be false.
  *
- *  Reset list of all assertions triggered.
+ * \since This function is available since SDL 2.0.0.
  *
- *  \sa SDL_GetAssertionReport
+ * \sa SDL_GetAssertionReport
  */
 extern DECLSPEC void SDLCALL SDL_ResetAssertionReport(void);
 
@@ -284,6 +317,6 @@ extern DECLSPEC void SDLCALL SDL_ResetAssertionReport(void);
 #endif
 #include "close_code.h"
 
-#endif /* _SDL_assert_h */
+#endif /* SDL_assert_h_ */
 
 /* vi: set ts=4 sw=4 expandtab: */

libs/SDL2/i686-w64-mingw32/include/SDL2/SDL_atomic.h

 /*
   Simple DirectMedia Layer
-  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+  Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>
 
   This software is provided 'as-is', without any express or implied
   warranty.  In no event will the authors be held liable for any damages
@@ -56,8 +56,8 @@
  * All of the atomic operations that modify memory are full memory barriers.
  */
 
-#ifndef _SDL_atomic_h_
-#define _SDL_atomic_h_
+#ifndef SDL_atomic_h_
+#define SDL_atomic_h_
 
 #include "SDL_stdinc.h"
 #include "SDL_platform.h"
@@ -89,25 +89,51 @@ extern "C" {
 typedef int SDL_SpinLock;
 
 /**
- * \brief Try to lock a spin lock by setting it to a non-zero value.
+ * Try to lock a spin lock by setting it to a non-zero value.
  *
- * \param lock Points to the lock.
+ * ***Please note that spinlocks are dangerous if you don't know what you're
+ * doing. Please be careful using any sort of spinlock!***
  *
- * \return SDL_TRUE if the lock succeeded, SDL_FALSE if the lock is already held.
+ * \param lock a pointer to a lock variable
+ * \returns SDL_TRUE if the lock succeeded, SDL_FALSE if the lock is already
+ *          held.
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_AtomicLock
+ * \sa SDL_AtomicUnlock
  */
 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicTryLock(SDL_SpinLock *lock);
 
 /**
- * \brief Lock a spin lock by setting it to a non-zero value.
+ * Lock a spin lock by setting it to a non-zero value.
+ *
+ * ***Please note that spinlocks are dangerous if you don't know what you're
+ * doing. Please be careful using any sort of spinlock!***
  *
- * \param lock Points to the lock.
+ * \param lock a pointer to a lock variable
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_AtomicTryLock
+ * \sa SDL_AtomicUnlock
  */
 extern DECLSPEC void SDLCALL SDL_AtomicLock(SDL_SpinLock *lock);
 
 /**
- * \brief Unlock a spin lock by setting it to 0. Always returns immediately
+ * Unlock a spin lock by setting it to 0.
+ *
+ * Always returns immediately.
  *
- * \param lock Points to the lock.
+ * ***Please note that spinlocks are dangerous if you don't know what you're
+ * doing. Please be careful using any sort of spinlock!***
+ *
+ * \param lock a pointer to a lock variable
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_AtomicLock
+ * \sa SDL_AtomicTryLock
  */
 extern DECLSPEC void SDLCALL SDL_AtomicUnlock(SDL_SpinLock *lock);
 
@@ -118,13 +144,16 @@ extern DECLSPEC void SDLCALL SDL_AtomicUnlock(SDL_SpinLock *lock);
  * The compiler barrier prevents the compiler from reordering
  * reads and writes to globally visible variables across the call.
  */
-#if defined(_MSC_VER) && (_MSC_VER > 1200)
+#if defined(_MSC_VER) && (_MSC_VER > 1200) && !defined(__clang__)
 void _ReadWriteBarrier(void);
 #pragma intrinsic(_ReadWriteBarrier)
 #define SDL_CompilerBarrier()   _ReadWriteBarrier()
 #elif (defined(__GNUC__) && !defined(__EMSCRIPTEN__)) || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x5120))
 /* This is correct for all CPUs when using GCC or Solaris Studio 12.1+. */
 #define SDL_CompilerBarrier()   __asm__ __volatile__ ("" : : : "memory")
+#elif defined(__WATCOMC__)
+extern __inline void SDL_CompilerBarrier(void);
+#pragma aux SDL_CompilerBarrier = "" parm [] modify exact [];
 #else
 #define SDL_CompilerBarrier()   \
 { SDL_SpinLock _tmp = 0; SDL_AtomicLock(&_tmp); SDL_AtomicUnlock(&_tmp); }
@@ -134,33 +163,58 @@ void _ReadWriteBarrier(void);
  * Memory barriers are designed to prevent reads and writes from being
  * reordered by the compiler and being seen out of order on multi-core CPUs.
  *
- * A typical pattern would be for thread A to write some data and a flag,
- * and for thread B to read the flag and get the data. In this case you
- * would insert a release barrier between writing the data and the flag,
+ * A typical pattern would be for thread A to write some data and a flag, and
+ * for thread B to read the flag and get the data. In this case you would
+ * insert a release barrier between writing the data and the flag,
  * guaranteeing that the data write completes no later than the flag is
- * written, and you would insert an acquire barrier between reading the
- * flag and reading the data, to ensure that all the reads associated
- * with the flag have completed.
+ * written, and you would insert an acquire barrier between reading the flag
+ * and reading the data, to ensure that all the reads associated with the flag
+ * have completed.
  *
- * In this pattern you should always see a release barrier paired with
- * an acquire barrier and you should gate the data reads/writes with a
- * single flag variable.
+ * In this pattern you should always see a release barrier paired with an
+ * acquire barrier and you should gate the data reads/writes with a single
+ * flag variable.
  *
  * For more information on these semantics, take a look at the blog post:
  * http://preshing.com/20120913/acquire-and-release-semantics
+ *
+ * \since This function is available since SDL 2.0.6.
  */
+extern DECLSPEC void SDLCALL SDL_MemoryBarrierReleaseFunction(void);
+extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquireFunction(void);
+
 #if defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))
 #define SDL_MemoryBarrierRelease()   __asm__ __volatile__ ("lwsync" : : : "memory")
 #define SDL_MemoryBarrierAcquire()   __asm__ __volatile__ ("lwsync" : : : "memory")
+#elif defined(__GNUC__) && defined(__aarch64__)
+#define SDL_MemoryBarrierRelease()   __asm__ __volatile__ ("dmb ish" : : : "memory")
+#define SDL_MemoryBarrierAcquire()   __asm__ __volatile__ ("dmb ish" : : : "memory")
 #elif defined(__GNUC__) && defined(__arm__)
-#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7EM__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__)
+#if 0 /* defined(__LINUX__) || defined(__ANDROID__) */
+/* Information from:
+   https://chromium.googlesource.com/chromium/chromium/+/trunk/base/atomicops_internals_arm_gcc.h#19
+
+   The Linux kernel provides a helper function which provides the right code for a memory barrier,
+   hard-coded at address 0xffff0fa0
+*/
+typedef void (*SDL_KernelMemoryBarrierFunc)();
+#define SDL_MemoryBarrierRelease()	((SDL_KernelMemoryBarrierFunc)0xffff0fa0)()
+#define SDL_MemoryBarrierAcquire()	((SDL_KernelMemoryBarrierFunc)0xffff0fa0)()
+#elif 0 /* defined(__QNXNTO__) */
+#include <sys/cpuinline.h>
+
+#define SDL_MemoryBarrierRelease()   __cpu_membarrier()
+#define SDL_MemoryBarrierAcquire()   __cpu_membarrier()
+#else
+#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7EM__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) || defined(__ARM_ARCH_8A__)
 #define SDL_MemoryBarrierRelease()   __asm__ __volatile__ ("dmb ish" : : : "memory")
 #define SDL_MemoryBarrierAcquire()   __asm__ __volatile__ ("dmb ish" : : : "memory")
-#elif defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6T2__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__)
+#elif defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6T2__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_5TE__)
 #ifdef __thumb__
 /* The mcr instruction isn't available in thumb mode, use real functions */
-extern DECLSPEC void SDLCALL SDL_MemoryBarrierRelease();
-extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquire();
+#define SDL_MEMORY_BARRIER_USES_FUNCTION
+#define SDL_MemoryBarrierRelease()   SDL_MemoryBarrierReleaseFunction()
+#define SDL_MemoryBarrierAcquire()   SDL_MemoryBarrierAcquireFunction()
 #else
 #define SDL_MemoryBarrierRelease()   __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" : : "r"(0) : "memory")
 #define SDL_MemoryBarrierAcquire()   __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" : : "r"(0) : "memory")
@@ -168,6 +222,7 @@ extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquire();
 #else
 #define SDL_MemoryBarrierRelease()   __asm__ __volatile__ ("" : : : "memory")
 #define SDL_MemoryBarrierAcquire()   __asm__ __volatile__ ("" : : : "memory")
+#endif /* __LINUX__ || __ANDROID__ */
 #endif /* __GNUC__ && __arm__ */
 #else
 #if (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x5120))
@@ -182,6 +237,25 @@ extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquire();
 #endif
 #endif
 
+/* "REP NOP" is PAUSE, coded for tools that don't know it by that name. */
+#if (defined(__GNUC__) || defined(__clang__)) && (defined(__i386__) || defined(__x86_64__))
+    #define SDL_CPUPauseInstruction() __asm__ __volatile__("pause\n")  /* Some assemblers can't do REP NOP, so go with PAUSE. */
+#elif (defined(__arm__) && defined(__ARM_ARCH) && __ARM_ARCH >= 7) || defined(__aarch64__)
+    #define SDL_CPUPauseInstruction() __asm__ __volatile__("yield" ::: "memory")
+#elif (defined(__powerpc__) || defined(__powerpc64__))
+    #define SDL_CPUPauseInstruction() __asm__ __volatile__("or 27,27,27");
+#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))
+    #define SDL_CPUPauseInstruction() _mm_pause()  /* this is actually "rep nop" and not a SIMD instruction. No inline asm in MSVC x86-64! */
+#elif defined(_MSC_VER) && (defined(_M_ARM) || defined(_M_ARM64))
+    #define SDL_CPUPauseInstruction() __yield()
+#elif defined(__WATCOMC__) && defined(__386__)
+    extern __inline void SDL_CPUPauseInstruction(void);
+    #pragma aux SDL_CPUPauseInstruction = ".686p" ".xmm2" "pause"
+#else
+    #define SDL_CPUPauseInstruction()
+#endif
+
+
 /**
  * \brief A type representing an atomic integer value.  It is a struct
  *        so people don't accidentally use numeric operations on it.
@@ -189,32 +263,73 @@ extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquire();
 typedef struct { int value; } SDL_atomic_t;
 
 /**
- * \brief Set an atomic variable to a new value if it is currently an old value.
+ * Set an atomic variable to a new value if it is currently an old value.
  *
- * \return SDL_TRUE if the atomic variable was set, SDL_FALSE otherwise.
+ * ***Note: If you don't know what this function is for, you shouldn't use
+ * it!***
  *
- * \note If you don't know what this function is for, you shouldn't use it!
-*/
+ * \param a a pointer to an SDL_atomic_t variable to be modified
+ * \param oldval the old value
+ * \param newval the new value
+ * \returns SDL_TRUE if the atomic variable was set, SDL_FALSE otherwise.
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_AtomicCASPtr
+ * \sa SDL_AtomicGet
+ * \sa SDL_AtomicSet
+ */
 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCAS(SDL_atomic_t *a, int oldval, int newval);
 
 /**
- * \brief Set an atomic variable to a value.
+ * Set an atomic variable to a value.
+ *
+ * This function also acts as a full memory barrier.
+ *
+ * ***Note: If you don't know what this function is for, you shouldn't use
+ * it!***
  *
- * \return The previous value of the atomic variable.
+ * \param a a pointer to an SDL_atomic_t variable to be modified
+ * \param v the desired value
+ * \returns the previous value of the atomic variable.
+ *
+ * \since This function is available since SDL 2.0.2.
+ *
+ * \sa SDL_AtomicGet
  */
 extern DECLSPEC int SDLCALL SDL_AtomicSet(SDL_atomic_t *a, int v);
 
 /**
- * \brief Get the value of an atomic variable
+ * Get the value of an atomic variable.
+ *
+ * ***Note: If you don't know what this function is for, you shouldn't use
+ * it!***
+ *
+ * \param a a pointer to an SDL_atomic_t variable
+ * \returns the current value of an atomic variable.
+ *
+ * \since This function is available since SDL 2.0.2.
+ *
+ * \sa SDL_AtomicSet
  */
 extern DECLSPEC int SDLCALL SDL_AtomicGet(SDL_atomic_t *a);
 
 /**
- * \brief Add to an atomic variable.
+ * Add to an atomic variable.
+ *
+ * This function also acts as a full memory barrier.
+ *
+ * ***Note: If you don't know what this function is for, you shouldn't use
+ * it!***
+ *
+ * \param a a pointer to an SDL_atomic_t variable to be modified
+ * \param v the desired value to add
+ * \returns the previous value of the atomic variable.
  *
- * \return The previous value of the atomic variable.
+ * \since This function is available since SDL 2.0.2.
  *
- * \note This same style can be used for any number operation
+ * \sa SDL_AtomicDecRef
+ * \sa SDL_AtomicIncRef
  */
 extern DECLSPEC int SDLCALL SDL_AtomicAdd(SDL_atomic_t *a, int v);
 
@@ -236,23 +351,54 @@ extern DECLSPEC int SDLCALL SDL_AtomicAdd(SDL_atomic_t *a, int v);
 #endif
 
 /**
- * \brief Set a pointer to a new value if it is currently an old value.
+ * Set a pointer to a new value if it is currently an old value.
  *
- * \return SDL_TRUE if the pointer was set, SDL_FALSE otherwise.
+ * ***Note: If you don't know what this function is for, you shouldn't use
+ * it!***
  *
- * \note If you don't know what this function is for, you shouldn't use it!
-*/
+ * \param a a pointer to a pointer
+ * \param oldval the old pointer value
+ * \param newval the new pointer value
+ * \returns SDL_TRUE if the pointer was set, SDL_FALSE otherwise.
+ *
+ * \since This function is available since SDL 2.0.0.
+ *
+ * \sa SDL_AtomicCAS
+ * \sa SDL_AtomicGetPtr
+ * \sa SDL_AtomicSetPtr
+ */
 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCASPtr(void **a, void *oldval, void *newval);
 
 /**
- * \brief Set a pointer to a value atomically.
+ * Set a pointer to a value atomically.
+ *
+ * ***Note: If you don't know what this function is for, you shouldn't use
+ * it!***
+ *
+ * \param a a pointer to a pointer
+ * \param v the desired pointer value
+ * \returns the previous value of the pointer.
  *
- * \return The previous value of the pointer.
+ * \since This function is available since SDL 2.0.2.
+ *
+ * \sa SDL_AtomicCASPtr
+ * \sa SDL_AtomicGetPtr
  */
 extern DECLSPEC void* SDLCALL SDL_AtomicSetPtr(void **a, void* v);
 
 /**
- * \brief Get the value of a pointer atomically.
+ * Get the value of a pointer atomically.
+ *
+ * ***Note: If you don't know what this function is for, you shouldn't use
+ * it!***
+ *
+ * \param a a pointer to a pointer
+ * \returns the current value of a pointer.
+ *
+ * \since This function is available since SDL 2.0.2.
+ *
+ * \sa SDL_AtomicCASPtr
+ * \sa SDL_AtomicSetPtr
  */
 extern DECLSPEC void* SDLCALL SDL_AtomicGetPtr(void **a);
 
@@ -263,6 +409,6 @@ extern DECLSPEC void* SDLCALL SDL_AtomicGetPtr(void **a);
 
 #include "close_code.h"
 
-#endif /* _SDL_atomic_h_ */
+#endif /* SDL_atomic_h_ */
 
 /* vi: set ts=4 sw=4 expandtab: */