Use memfd_create() to allocate the temporary SHM backing file in memory, and set the size with posix_fallocate(), which will return an error on insufficient space vs ftruncate(), which will silently succeed and allow a SIGBUS error to occur if the unbacked memory is accessed.
Additionally, make the legacy path more robust by unlinking the temp file, so it won't persist after close, and unmapping the shared memory buffer.
- Always use internal qsort and bsearch implementation.
- add "_r" reentrant versions.
The reasons for always using the internal versions is that the C runtime
versions' callbacks are not mark STDCALL, so we would have add bridge
functions for them anyhow, The C runtime qsort_r/qsort_s have different
orders of arguments on different platforms, and most importantly: qsort()
isn't a stable sort, and isn't guaranteed to give the same ordering for
two objects marked as equal by the callback...as such, Visual Studio and
glibc can give different sort results for the same data set...in this
sense, having one piece of code shared on all platforms makes sense here,
for reliabillity.
bsearch does not have a standard _r version at all, and suffers from the
same SDLCALL concern. Since the code is simple and we would have to work
around the C runtime, it's easier to just go with the built-in function
and remove all the CMake C runtime tests.
Fixes#9159.
This pull request adds an implementation of a Vulkan Render backend to SDL. I have so far tested this primarily on Windows, but also smoke tested on Linux and macOS (MoltenVK). I have not tried it yet on Android, but it should be usable there as well (sans any bugs I missed). This began as a port of the SDL Direct3D12 Renderer, which is the closest thing to Vulkan as existed in the SDL codebase. The shaders are more or less identical (with the only differences being in descriptor bindings vs root descriptors). The shaders are built using the HLSL frontend of glslang.
Everything in the code is pure Vulkan 1.0 (no extensions), with the exception of HDR support which requires the Vulkan instance extension `VK_EXT_swapchain_colorspace`. The code could have been simplified considerably if I used dynamic rendering, push descriptors, extended dynamic state, and other modern Vulkan-isms, but I felt it was more important to make the code as vanilla Vulkan as possible so that it would run on any Vulkan implementation.
The main differences with the Direct3D12 renderer are:
* Having to manage renderpasses for performing clears. There is likely some optimization that would still remain for more efficient use of TBDR hardware where there might be some unnecessary load/stores, but it does attempt to do clears using renderpasses.
* Constant buffer data couldn't be directly updated in the command buffer since I didn't want to rely on push descriptors, so there is a persistently mapped buffer with increasing offset per swapchain image where CB data gets written.
* Many more resources are dependent on the swapchain resizing due to i.e. Vulkan requiring the VkFramebuffer to reference the VkImageView of the swapchain, so there is a bit more code around handling that than was necessary in D3D12.
* For NV12/NV21 textures, rather than there being plane data in the texture itself, the UV data is placed in a separate `VkImage`/`VkImageView`.
I've verified that `testcolorspace` works with both sRGB and HDR linear. I've tested `testoverlay` works with the various YUV/NV12/NV21 formats. I've tested `testsprite`. I've checked that window resizing and swapchain out-of-date handling when minimizing are working. I've run through `testautomation` with the render tests. I also have run several of the tests with Vulkan validation and synchronization validation. Surely I will have missed some things, but I think it's in a good state to be merged and build out from here.
Mingw seems to have a bad pow implementation in the C runtime:
'Pow(-72.300000,12.000000), expected [20401381050275984310272.000000], got 20401381050275996893184.000000': Failed
Many SDL subsystems depend on being able to see time passing. If you are porting to a new platform, you'll need to fill in a timer implementation as part of the initial port.
Fixes https://github.com/libsdl-org/SDL/issues/8850
- check libiconv with a linkage test with iconv.h included
- check libc iconv with a linkage test with iconv.h included
and LIBICONV_PLUG defined (in case libiconv header is in
include path)
- add new configuration option to prefer iconv from libiconv,
if available, over the libc version: SDL_LIBICONV, defaults
to disabled.
- remove FindIconv + pkg_check_modules for iconv, and use our
manual iconv finding only
- change FreeBSD specific LIBICONV_PLUG define in SDL_iconv.c
to configuration result.
Semphris
Frank Praznik
Anonymous Maarten
Ryan C. Gordon
Dan Ginsburg
Sam Lantinga
Julian Uy
Ozkan Sezer
Sylvain