SDL_strcasecmp (even when calling into a C runtime) does not work with
Unicode chars, and depending on the user's locale, might not work with
even basic ASCII strings.
This implements the function from scratch, using "case-folding,"
which is a more robust method that deals with various languages. It
involves a hashtable of a few hundred codepoints that are "uppercase" and
how to map them to lowercase equivalents (possibly increasing the size of
the string in the process). The vast majority of human languages (and
Unicode) do not have letters with different cases, but still, this static
table takes about 10 kilobytes on a 64-bit machine.
Even this will fail in one known case: the Turkish 'i' folds differently
if you're writing in Turkish vs other languages. Generally this is seen as
unfortunate collateral damage in cases where you can't specify the language
in use.
In addition to case-folding the codepoints, the new functions also know how
to decode the various formats to turn them into codepoints in the first
place, instead of blindly stepping by one byte (or one wchar_t) per
character.
Also included is casefolding.txt from the Unicode Consortium and a perl
script to generate the hashtable from that text file, so we can trivially
update this if new languages are added in the future.
A simple test using the new function:
```c
#include <SDL3/SDL.h>
int main(void)
{
const char *a = "α ε η";
const char *b = "Α Ε Η";
SDL_Log(" strcasecmp(\"%s\", \"%s\") == %d\n", a, b, strcasecmp(a, b));
SDL_Log("SDL_strcasecmp(\"%s\", \"%s\") == %d\n", a, b, SDL_strcasecmp(a, b));
return 0;
}
```
Produces:
```
INFO: strcasecmp("α ε η", "Α Ε Η") == 32
INFO: SDL_strcasecmp("α ε η", "Α Ε Η") == 0
```
glibc strcasecmp() fails to compare a Greek lowercase string to its uppercase
equivalent, even with a UTF-8 locale, but SDL_strcasecmp() works.
Other SDL_stdinc.h functions are changed to be more consistent, which is to
say they now ignore any C runtime and often dictate that only English-based
low-ASCII works with them.
Fixes Issue #9313.
This was previous behavior that used window userdata and was lost during the move to properties. Renderer objects need to be cleaned up when their associated windows are destroyed, or they can be leaked and backend refcounts won't be properly updated, leading to them not being properly shut down when SDL_Quit() is called.
The dimensions for fixed-size state set via window flags will be applied later in the window creation process.
Restores the window to the proper windowed size when leaving fullscreen.
I believe there was a O(n^2) device walking issues on startup
- MaybeAddDevice gets called for every device at startup
- MaybeAddDevice calls IsJoystick
- IsJoystick calls SDL_UDEV_GetProductInfo
- SDL_UDEV_GetProductInfo calls udev_enumerate_scan_devices
- udev_enumerate_scan_devices walks all the devices
Prior to commit 3b1e0e1 this was mostly masked as IsJoystick only
called SDL_UDEV_GetProductInfo when a JSIOCGNAME ioctl was
successful. This fixes the O(n^2) behaviour by directly getting
the device via udev_device_new_from_devnum (based on type, major,
and minor number) instead of enumerating everything via
udev_enumerate_scan_devices and matching on name.