The current way "arrays" from XML files are loaded (before this commit
is applied) goes something like this:
1. Read the buffer of the contents of the tag using TinyXML-2.
2. Allocate a buffer on the heap of the same size, and copy the
existing buffer to it. (This is what the statement `std::string
TextString = pText;` does.)
3. For each delimiter in the heap-allocated buffer...
a. Allocate another buffer on the heap, and copy the characters from
the previous delimiter to the delimiter you just hit.
b. Then allocate the buffer AGAIN, to copy it into an std::vector.
4. Then re-allocate every single buffer YET AGAIN, because you need to
make a copy of the std::vector in split() to return it to the caller.
As you can see, the existing way uses a lot of memory allocations and
data marshalling, just to split some text.
The problem here is mostly making a temporary std::vector of split text,
before doing any actual useful work (most likely, putting it into an
array or ANOTHER std::vector - if the latter, then that's yet another
memory allocation on top of the memory allocation you already did; this
memory allocation is unavoidable, unlike the ones mentioned earlier,
which should be removed).
So I noticed that since we're iterating over the entire string once
(just to shove its contents into a temporary std::vector), and then
basically iterating over it again - why can't the whole thing just be
more immediate, and just be iterated over once?
So that's what I've done here. I've axed the split() function (both of
them, actually), and made next_split() and next_split_s().
next_split() will take an existing string and a starting index, and it
will find the next occurrence of the given delimiter in the string. Once
it does so, it will return the length from the previous starting index,
and modify your starting index as well. The price for immediateness is
that you're supposed to handle keeping the index of the previous
starting index around in order to be able to use the function; updating
it after each iteration is also your responsibility.
(By the way, next_split() doesn't use SDL_strchr(), because we can't get
the length of the substring for the last substring. We could handle this
special case specifically, but it'd be uglier; it also introduces
iterating over the last substring twice, when we only need to do it
once.)
next_split_s() does the same thing as next_split(), except it will copy
the resulting substring into a buffer that you provide (along with its
size). Useful if you don't particularly care about the length of the
substring.
All callers have been updated accordingly. This new system does not make
ANY heap allocations at all; at worst, it allocates a temporary buffer
on the stack, but that's only if you use next_split_s(); plus, it'd be a
fixed-size buffer, and stack allocations are negligible anyway.
This improves performance when loading any sort of XML file, especially
loading custom levels - which, on my system at least, I can noticeably
tell (there's less of a freeze when I load in to a custom level with
lots of scripts). It also decreases memory usage, because the heap isn't
being used just to iterate over some delimiters when XML files are
loaded.
These comments were probably remnants of some late-night coding session
or something. Anyway, they're not needed; there's nothing to do with SDL
here, and the "Init" is obvious because the function is a constructor.
Contents and scripts should be reset in editorclass::reset(); there's no
reason to reset them again right before you load them from an XML file
in editorclass::load().
Additionally, the resets now consistently use SDL_zeroa() (for contents)
and scriptclass::clearcustom() (for scripts).
I'm partial to slash-asterisk-style comments, so I'll use those here.
Also, having a space after the start of comments is good. I've also
removed the "Add the script if we have a preceding header" comments
since it can be inferred by reading the surrounding code.
Instead of checking the length() of an std::string, just check if
pText[0] is equal to '\0'.
This will have to be done anyway, because I'm going to get rid of the
std::string allocation here, and I noticed this inefficiency in the
indentation, so I'm going to remove it.
The actual unindent will be done in the next commit.
This now means every XML array loading is done with common,
re-duplicated code. The only exceptions to this are special cases other
than the the majority of cases; the majority being a simple matter of
reading an array of integers and putting it into another array.
Seems like the only reason I hadn't caught the <customlevelscore> tag
until now was because I was focused on de-duplicating all the array
loads in Game::loadstats() and below, forgetting about
Game::loadcustomlevelstats().
In order to be able to use the LOAD_ARRAY() and LOAD_ARRAY_RENAME()
macros in Game::loadcustomlevelstats(), they have to be moved to earlier
in the file.
Even if split() didn't use the STL, using this function here is a bit
unnecessary, because a simple SDL_strchr() suffices. Refactoring split()
to not use the STL will break this caller anyway, so I might as well
just refactor this to not use split() in the first place.
This refactor also properly checks if the inputs are valid integers. And
since split() is no longer used, it also rejects inputs ending with a
trailing comma as being invalid, too; this didn't happen previously.
It's intentional that I used is_number() here instead of
is_positive_num(), thus accepting negative numbers; in the future it
might be possible to have negative room coordinates.
Valgrind reported this.
The error here is that the buffer here is only guaranteed to be
initialized up until (and including) the null-terminator, by
SDL_snprintf(). Iterating over the entire allocated buffer is bad and I
should feel bad as the girl who wrote this code; doing that reads
uninitialized memory and passes it to SDL_tolower().
As a bonus, the iterator increment is now a preincrement instead of a
postincrement.
This fixes memory leaking every single time a file gets loaded(!) when
the list of custom levels gets loaded(!!!), which Valgrind reports. This
memory leak is completely my bad; 2.2 properly frees the loaded file,
and VCE uses an std::unique_ptr - which I decided to ignore and not
think about why it would be there.
It's safe to do this free after uMem gets copied into std::string;
although, in the future, I *am* thinking about refactoring this function
(and the tag finder function) to not use std::strings, and I'll have to
be careful to make sure that the memory management with the file is
correct when I do so.
This makes the freesrc argument of Mix_LoadMUS_RW() 1 instead of 0. If
the argument is nonzero, then the passed SDL_RWops will be automatically
freed when m_music is freed, too.
I don't know why this was 0 before. Setting it to 1 fixes a memory leak
that Valgrind reports (which turns into an actual leak every time custom
assets are mounted or unmounted).
This adds a check that the pointer passed to
FILESYSTEM_loadFileToMemory() isn't NULL, and if it is, just returns
early in the function, instead of continuing later and producing a
different, slightly-misleading error message.
Previously, it was guarded behind a check for the length, which is... I
guess still perfectly fine behavior, but there's no reason to have a
length check here; FILESYSTEM_freeMemory() uses SDL_free(), which does a
check that the pointer passed is non-NULL (the pointer that is passed
here, despite not being initialized upon declaration, is guaranteed to
be initialized by FILESYSTEM_loadFileToMemory() anyway, so).
Following Ethan's example of bailing (calling VVV_exit()) if
binaryBlob::unPackBinary() couldn't allocate memory, I've searched
through and found every SDL_malloc(), then made sure that if it returned
NULL, the caller would bail (because you can't do much when you're out
of memory).
There should probably be an error message printed when the process is
out of memory, but unPackBinary() doesn't print an error message for
being out of memory, so this can probably be added later. (Also we don't
really have a logging system, I'd like to have something like that added
in first before adding more messages.)
Also, this doesn't account for any allocators used by STL stuff, but
we're working on removing the STL, and allocation failure just results
in an abort anyway, so there's not really a problem there.
Wow, there are a lot of these. All of these exit paths now use
VVV_exit() instead, which attempts to save unlock.vvv and settings.vvv,
and also frees all resources so Valgrind is happy. This is a good thing,
because previously unlock.vvv/settings.vvv wouldn't be written to if we
decided to bail for a given reason.
It should be between the include of the corresponding header file for
the source file (Script.h) and the includes of other local header files
(the files that are specific to this codebase only); this is the
convention that includes in all other source files follow.
However, it seems like I misplaced this, so I'm fixing it now.
This is just a function that calls the cleanup() in main.cpp, as well as
calls exit().
I would have liked to use SDL_ExitProcess() here, because that function
has ifdefs for different runtime environments. But alas, it's an
internal function and isn't exported. Ah well; exit() seems to be fine
anyway.
If there's a resource that doesn't otherwise need to be cleaned up and
is still alive upon program shutdown, then it should go in cleanup().
This cleans up Screen, GraphicsResources, Graphics buffers, Graphics
tiles, and musicclass audio upon program shutdown.
Even we technically don't NEED to clean these resources up ourselves
(the kernel is going to get rid of all of it anyway, else it'd be a
security problem), I'm doing this because otherwise Valgrind will
complain about these, and then it'd be difficult to see which memory
leaks are real and which are just "well this isn't really a leak but you
haven't freed this thing when the process exited, and that's technically
what a memory leak is".
These are all resources whose cleanup functions can be safely called
even if they haven't initialized anything yet.
This isn't a memory leak (not even Valgrind complains), because it gets
properly cleaned up in GraphicsResources::destroy(). Still, it's memory
that is just laying around not being used, and in the name of
deallocating things as soon as you no longer need them, we should
deallocate the base tilesheet images after we split all of them into
tiles.
This reduces the memory cost of all tilesheet images by half, since we
were essentially keeping around duplicates for nothing; this doesn't
really have much of an impact with conventional tilesheet sizes, since
they're usually small enough, but since 2.3 allowed for tilesheet images
of any size, this is a pretty big deal for really big tilesheet images.
It's okay to do this, even though they also get freed in
GraphicsResources::destroy(), because SDL_FreeSurface() does a NULL
check on the pointer passed to it, and we set the pointer to NULL after
freeing the surfaces.
A quick glance at PhysFS source code will show that PhysFS will bail if
PHYSFS_deinit() is called if it's not initialized.
"Bail" here just means setting an error code and returning early, so
it's not that bad. Still, it's the principle of the thing, and I just
want to ensure that FILESYSTEM_deinit() can be safely called no matter
if the filesystem hasn't initialized yet; having an error set by PhysFS
kind of taints the whole safety thing, even if it does nothing wrong,
no?
(although, speaking of which, we should be handling all errors by
PhysFS, but that's for later...)
These FIXME comments are still correct about code duplication, but
they're incorrect about where exactly the original code is after the
original code got moved around. So I've fixed them to refer to the
correct locations.
We really should get around to de-duplicating the code mentioned in
these comments...
Since musicWriteBlob is a temporary object that gets destroyed at the
end of musicclass::init(), in order to make sure we don't leak memory
and lose all the pointers to the blocks we just allocated in
musicWriteBlob, we need to call its clear() method after writing
BinaryMusic.vvv.
musicReadBlob was used for both MMMMMM and PPPPPP soundtracks. This
causes a memory leak if you have mmmmmm.vvv installed, because the
pointers holding each allocated block of MMMMMM would be lost when
PPPPPP got loaded. Valgrind complains about this memory leak.
This is in contrast to 2.2 and previous behavior, where musicReadBlob
was only a temporary object instead of being held in musicclass.
However, this wasn't really a memory leak (moreso something that just
didn't get cleaned up when closing the game), but it did get turned into
a leak when per-level assets mounting and unmounting got introduced in
2.3 (loading a level with custom assets after starting the game with an
mmmmmm.vvv, or exiting out of a level that had an mmmmmm.vvv, would
cause the game to leak memory). Leo recognized this, and moved
musicReadBlob onto musicclass in a separate 2.3 PR, but either he didn't
think about what was happening here too closely, or he didn't use
Valgrind, because he forgot about the memory leak caused by re-using the
same binaryBlob for PPPPPP and MMMMMM.
So instead, just use two different binaryBlob objects for MMMMMM and
PPPPPP. That way, no memory leaks happen.
I'm going to introduce another binaryBlob object in to the mix, and I
want to be able to re-use an existing FOREACH_TRACK #define without
having to copy-paste it again. So, TRACK_NAMES now takes in a blob
parameter, which will be passed to the temporary FOREACH_TRACK #define.
This removes the music cleanup code from musicclass::init(), and
requires that we also call destroy() in Graphics::reloadresources().
This is because we'll need to re-use the musicclass cleanup code
elsewhere, and we don't want to copy-paste the cleanup code. Or at
least, I don't (but I'm not a game dev, game devs copy-paste all the
friggin' time).
It doesn't feel quite write leaving all the buffer creation code in
main(), even though it's perfectly okay to do so and it doesn't result
in any memory mismanagement that Valgrind can report; so I'm factoring
all of it out to a separate function, Graphics::create_buffers().
As a bonus, we no longer have to keep qualifying with `graphics.` in the
buffer creation code, which is nice.
These destroy all the buffers that are created on the Graphics class.
Since these buffers can't be created at the same time as the rest of
Graphics is (due to the fact that they require knowing the pixel format
of the game screen), they can't be destroyed at the same as the rest of
Graphics is, either.
This is a very complicated way of zeroing out grphx (instead of using
SDL_zero()), which itself is completely unnecessary because grphx.init()
gets called immediately afterwards anyway.
It should be next-line brace, not same-line brace. Even in a codebase
that uses same-line braces everywhere, I still prefer having next-line
braces inside functions (because they're at the top level, and you can't
next them). But regardless, this should still be next-line brace like
(most of) the rest of the codebase.
The function previously conditionally freed a m_memblocks pointer if its
corresponding m_headers was valid. This makes me slightly worried about
the possibility that memory would be allocated, but the header would
still be marked as invalid.
I don't see how that could happen, but it's better to be safe than
sorry. SDL_free() does a guaranteed NULL pointer check (like most SDL
functions), so it's okay to pass NULL pointers to it.
Just to be sure, I'm also zeroing m_memblocks and m_headers after
freeing everything in the function.
MSVC complains about these, doesn't seem like GCC does. These can be
safely removed because they're unreachable, and they always follow a
case-switch or similar that has a default case which this code is a
duplicate of anyway. (Unless it isn't, in which case all the better to
remove it, becausee otherwise it looks misleading or confusing to casual
glances at the code.)
find_tag() would commit out-of-bounds indexing if someone made a level
file with malformed XML entity encodings in the metadata tags.
This would happen if the end of the string followed immediately after an
ampersand and hash, or if there wasn't a semicolon ending an XML entity.
Valgrind complains about these, so I've fixed it.
This fixes a bug where "12" gets properly evaluated as 12, but "148"
gets evaluated as 1408. It's because `place` gets multiplied by `radix`
again, so `retval` gets multipled by 100 instead of 10.
There's no reason to have a `place` variable, so I've removed it
entirely. This simplifies the function a little bit.
The previous person who wrote this (a girl named Misa) clearly didn't
understand the reason why you couldn't compare line[line.length()-1]
directly to a string literal. It's because the former is a char, and the
latter is a pointer to a char. Both are ints, so it compiles fine, but
it doesn't do what you want it to.
Why not just make the latter a char instead of a string literal? Well,
because you can, but also I clearly didn't think this through earlier,
so that's why I didn't do it in the first place.
But this is fixed now.
This avoids an unnecessary copy of the input std::vector, since we don't
need to modify it for anything. This cuts down on unnecessary memory
operations.
Apart from the std::string, this function no longer uses the STL.
ss_toi() is a simple function - it converts the input into an int,
taking as many digits as possible until it reaches a non-digit
character, at which point it stops. It's trivial to implement this
without the STL.
I could've used Int() here, but that would've required copying the
string to a temporary buffer to insert a null-terminator (we can't just
use a pointer-and-length data type either, the string functions don't
operate like that - one disadvantage of C strings!). Instead, I decided
to implement my own conversion to int here, because I don't think the
way we humans write our Arabic numerals is going to change anytime soon.
Also, the std::string input is now passed by const reference, instead of
making a copy - cutting down on unnecessary memory operations.
