VVV_min/max are functions that only operate on ints, and SDL_min/max are
macros that operate on any type but double-evaluate everything.
I know I more-or-less said earlier that SDL_min/max were dumb but I've
changed my mind and think it's better to use them, taking care to make
sure you don't double-evaluate, rather than trying to generate your own
litany of functions with either your own hand-rolled generation macros,
C++ templates, C11 generics, or GCC extensions (that last one you'd
technically use in a macro but it doesn't really matter), all of which
have more downsides than just not double-evaluating.
And the upside of not double-evaluating is that you're disencouraged
from having really complicated single-line min/max expressions and
encouraged to precompute the values beforehand anyway so the final
min/max is more readable. And furthermore you'll notice when you
yourself end up doing double-evaluations anyway. I removed a couple
instances of Graphics::len() being double-evaluated in this commit (as
well as cleaned up some other min/max-using code). Although the only
downside to those double-evaluations was unnecessary computation,
rather than checking the wrong result or having multiple side effects,
thankfully, it's still good to minimize double-evaluations where
possible.
Apparently in C, if you have `void test();`, it's completely okay to do
`test(2);`. The function will take in the argument, but just discard it
and throw it away. It's like a trash can, and a rude one at that. If you
declare it like `void test(void);`, this is prevented.
This is not a problem in C++ - doing `void test();` and `test(2);` is
guaranteed to result in a compile error (this also means that right now,
at least in all `.cpp` files, nobody is ever calling a void parameter
function with arguments and having their arguments be thrown away).
However, we may not be using C++ in the future, so I just want to lay
down the precedent that if a function takes in no arguments, you must
explicitly declare it as such.
I would've added `-Wstrict-prototypes`, but it produces an annoying
warning message saying it doesn't work in C++ mode if you're compiling
in C++ mode. So it can be added later.
During 2.3 development, there's been a gradual shift to using SDL stdlib
functions instead of libc functions, but there are still some libc
functions (or the same libc function but from the STL) in the code.
Well, this patch replaces all the rest of them in one fell swoop.
SDL's stdlib can replace most of these, but its SDL_min() and SDL_max()
are inadequate - they aren't really functions, they're more like macros
with a nasty penchant for double-evaluation. So I just made my own
VVV_min() and VVV_max() functions and placed them in Maths.h instead,
then replaced all the previous usages of min(), max(), std::min(),
std::max(), SDL_min(), and SDL_max() with VVV_min() and VVV_max().
Additionally, there's no SDL_isxdigit(), so I just implemented my own
VVV_isxdigit().
SDL has SDL_malloc() and SDL_free(), but they have some refcounting
built in to them, so in order to use them with LodePNG, I have to
replace the malloc() and free() that LodePNG uses. Which isn't too hard,
I did it in a new file called ThirdPartyDeps.c, and LodePNG is now
compiled with the LODEPNG_NO_COMPILE_ALLOCATORS definition.
Lastly, I also refactored the awful strcpy() and strcat() usages in
PLATFORM_migrateSaveData() to use SDL_snprintf() instead. I know save
migration is getting axed in 2.4, but it still bothers me to have
something like that in the codebase otherwise.
Without further ado, here is the full list of functions that the
codebase now uses:
- SDL_strlcpy() instead of strcpy()
- SDL_strlcat() instead of strcat()
- SDL_snprintf() instead of sprintf(), strcpy(), or strcat() (see above)
- VVV_min() instead of min(), std::min(), or SDL_min()
- VVV_max() instead of max(), std::max(), or SDL_max()
- VVV_isxdigit() instead of isxdigit()
- SDL_strcmp() instead of strcmp()
- SDL_strcasecmp() instead of strcasecmp() or Win32 strcmpi()
- SDL_strstr() instead of strstr()
- SDL_strlen() instead of strlen()
- SDL_sscanf() instead of sscanf()
- SDL_getenv() instead of getenv()
- SDL_malloc() instead of malloc() (replacing in LodePNG as well)
- SDL_free() instead of free() (replacing in LodePNG as well)
