Author: James Zipperer <james.zipperer@synapse.com>
Date: Sun Aug 21 01:19:19 2016 -0700
bugfix for controller / joystick add / remove being in the event queue at the same time
The repro steps were this:
1. run an sdl2 winrt/uwp app, on Win10, v10.0.10586.0 or higher
2. hide the cursor, via a call to SDL_ShowCursor(0)
3. make the Win10 game bar appear, by pressing the Windows + G hotkey
4. observe that the mouse cursor appears, in order to interact with the
game bar (this is expected behavior)
5. make the Win10 game bar disappear, either by pressing the Windows + G hotkey
again, or clicking somewhere in the app
EXPECTED RESULT: cursor disappears, as game bar disappears
ACTUAL RESULT: cursor didn't always disappear
Moved this code from winmm into core so both can use it.
DirectSound (at least on Win10) also returns truncated device names, even
though it's handed in as a string pointer and not a static-sized buffer. :/
The Windows 10 Anniversary Update (1607) breaks the method uses that SDL uses to
detect XInput devices. That is, on Windows 10 Anniversary Update, it is no longer
possible to query RAWINPUT for HID devices, and check for "IG_" in the device name.
Presumably, this will be fixed in the future.
This patch works around the issue by adding the Xbox One controller series to the
well-known device list.
This skips the more expensive RAWINPUT check for those devices, and causes them to
be detected as XInput devices once again.
Otherwise, if you had a massive, one-time queue buildup, the memory from that
remains allocated until you close the device. Also, if you are just using a
reasonable amount of space, this would previously cause you to reallocate it
over and over instead of keeping a little bit of memory around.
I think this was important for SDL 1.2 because some targets needed
special device memory for DMA buffers or locked memory buffers for use in
hardware interrupts or something, but since it just defines to SDL_malloc
and SDL_free now, I took it out for clarity's sake.
- It's now always called if device->hidden isn't NULL, even if OpenDevice()
failed halfway through. This lets implementation code not have to clean up
itself on every possible failure point; just return an error and SDL will
handle it for you.
- Implementations can assume this->hidden != NULL and not check for it.
- implementations don't have to set this->hidden = NULL when done, because
the caller is always about to free(this).
- Don't reset other fields that are in a block of memory about to be free()'d.
- Implementations all now free things like internal mix buffers last, after
closing devices and such, to guarantee they definitely aren't in use anymore
at the point of deallocation.
Turns out that libartsc isn't thread-safe, so if we run a capture and playback
device at the same time, it often crashes in arts's internal event loop.
We could throw mutexes around the read/write calls, but these are meant to
block, so one device could cause serious latency and stutter in the other.
Since this audio target isn't in high-demand (Ubuntu hasn't offered a libartsc
package for years), I'm just backing out the capture support. If someone needs
it, they can pull it out of the revision history.
