Dvoid from Discord just reported a crash when trying to load a
custom tiles2.png that was encoded weirdly.
The problem is that we don't check the return value from LodePNG, so
LodePNG gives us a null pointer, and then
SDL_CreateRGBSurfaceWithFormatFrom doesn't check this null pointer,
which then propagates until we crash in SDL_ConvertSurfaceFormat (or
rather, one of its sub-functions), and we would probably crash somewhere
else anyway if it continued.
After properly checking LodePNG's return value, along with printing the
error, it turns out that Dvoid's custom tiles2.png had an "invalid CRC".
I don't know what this means but it sounds worrying. `feh` can read the
file correctly but it also reports a "CRC error".
This fixes the color ordering of every SDL_Surface in the game.
Basically, images need to be loaded in ABGR format (except if they don't
have alpha, then you use RGB? I'm not sure what's going on here), and
then they will be converted to RGB/RGBA afterwards.
Due to the surfaces actually being BGR/BGRA, the game used to use
getRGBA/getRGB to swap the colors back around to BGRA/BGR, but I've
fixed those too.
I don't want to add too many asserts, because sometimes it's okay if a
file is missing (mmmmmm.vvv). But currently, the game basically expects
all images and sound effects to be present. That might change in the
future, but for now, these asserts are okay.
So, the codebase was kind of undecided about who is responsible for
initializing the parameters passed to FILESYSTEM_loadFileToMemory() - is
it the caller? Is it FILESYSTEM_loadFileToMemory()? Sometimes callers
would initialize one variable but not the other, and it was always a
toss-up whether or not FILESYSTEM_loadFileToMemory() would end up
initializing everything in the end.
All of this is to say that the game dereferences an uninitialized
pointer if it can't load a sound effect. Which is bad. Now, I could
either fix that single case, or fix every case. Judging by the title of
this commit, you can infer that I decided to fix every case - fixing
every case means not just all cases that currently exist (which, as far
as I know, is only the sound effect one), but all cases that could exist
in the future.
So, FILESYSTEM_loadFileToMemory() is now guaranteed to initialize its
parameters even if the file fails to be loaded. This is better than
passing the responsibility to the caller anyway, because if the caller
initialized it, then that would be wasted work if the file succeeds
anyway because FILESYSTEM_loadFileToMemory() will overwrite it, and if
the file fails to load, well that's when the variables get initialized
anyway.
Default function arguments are the devil, and it's better to be more
explicit about what you're passing into the function. Also because we
might become C-only in the future and to help faciliate that, we should
get rid of C++-isms like default function arguments now.
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)
This patch cleans up unnecessary exports from header files (there were
only a few), as well as adds the static keyword to all symbols that
aren't exported and are specific to a file. This helps the linker out in
not doing any unnecessary work, speeding it up and avoiding silent
symbol conflicts (otherwise two symbols with the same name (and
type/signature in C++) would quietly resolve as okay by the linker).
Okay, so basically here's the include layout that this game now
consistently uses:
[The "main" header file, if any (e.g. Graphics.h for Graphics.cpp)]
[blank line]
[All system includes, such as tinyxml2/physfs/utfcpp/SDL]
[blank line]
[All project includes, such as Game.h/Entity.h/etc.]
And if applicable, another blank line, and then some special-case
include screwy stuff (take a look at editor.cpp or FileSystemUtils.cpp,
for example, they have ifdefs and defines with their includes).
I ran the game through cppcheck and it spat out a bunch of member
attributes that weren't being initialized. So I initialized them.
In the previous version of this commit, I added constructors to
GraphicsResources, otherlevelclass, labclass, warpclass, and finalclass,
but flibit says this changes the code flow enough that it's risky to
merge before 2.4, so I got rid of those constructors, too.
These unused vars are:
- Graphics::bfontmask_rect
- Graphics::backgrounds
- Graphics::bfontmask
- GraphicsResources::im_bfontmask
While it seems that Graphics::backgrounds was indexed in
Graphics::drawbackground(), in reality there was never anything in that
vector and thus actually using it would cause a segfault.
This commit makes `help`, `graphics`, `music`, `game`, `key`, `map`, and
`obj` essentially static global objects that can be used everywhere.
This is useful in case we ever need to add a new function in the future,
so we don't have to bother with passing a new argument in which means we
have to pass a new argument in to the function that calls that function
which means having to pass a new argument into the function that calls
THAT function, etc. which is a real headache when working on fan mods of
the source code.
Note that this changes NONE of the existing function signatures, it
merely just makes those variables accessible everywhere in the same way
`script` and `ed` are.
Also note that some classes had to be initialized after the filesystem
was initialized, but C++ would keep initializing them before the
filesystem got initialized, because I *had* to put them at the top of
`main.cpp`, or else they wouldn't be global variables.
The only way to work around this was to use entityclass's initialization
style (which I'm pretty sure entityclass of all things doesn't need to
be initialized this way), where you actually initialize the class in an
`init()` function, and so then you do `graphics.init()` after the
filesystem initialization, AFTER doing `Graphics graphics` up at the
top.
I've had to do this for `graphics` (but only because its child
GraphicsResources `grphx` needs to be initialized this way), `music`,
and `game`. I don't think this will affect anything. Other than that,
`help`, `key`, and `map` are still using the C++-intended method of
having ClassName::ClassName() functions.
