Codechange: automatic adding of _t to (u)int types, and WChar to char32_t

for i in `find src -type f|grep -v 3rdparty/fmt|grep -v 3rdparty/catch2|grep -v 3rdparty/opengl|grep -v stdafx.h`; do sed 's/uint16& /uint16 \&/g;s/int8\([ >*),;[]\)/int8_t\1/g;s/int16\([ >*),;[]\)/int16_t\1/g;s/int32\([ >*),;[]\)/int32_t\1/g;s/int64\([ >*),;[]\)/int64_t\1/g;s/ uint32(/ uint32_t(/g;s/_uint8_t/_uint8/;s/Uint8_t/Uint8/;s/ft_int64_t/ft_int64/g;s/uint64$/uint64_t/;s/WChar/char32_t/g;s/char32_t char32_t/char32_t WChar/' -i $i; done

Change: Allow dedicated server to use threaded saves. (#10787)

Co-authored-by: Jonathan G Rennison <j.g.rennison@gmail.com>

Change: include fmt.h C++ headers in stdafx.h

This to prevent compilation issues between runs with and without precompiled
headers. Also remove the headers from the rest of the code base as they are
not needed there anymore, although they do relatively little harm.

Fix: crash in emscripten when saving games (#10758)

Don't allocate 128KB on stack, but rather on the heap.

Codechange: Place gamelog into its own class, along with internal data.

Data is now stored in vectors to avoid manual memory management and
passing lengths around.

Fix #10224: Don't fiddle with fast-forward when saving. (#10230)

The original comment about saving with fast-forward on was written 18 years
ago, and predates lots of changes to how saveload work.

Feature: Persistant rotation of numbered auto/netsave after restart (#9397)

It was always starting from 0 on openttd restart.
Now the most recent auto/netsave number will be used as a base to generate the next filename.

Fix: reduce the amount of debug messages on -dsl=2 (#9420)

LoadCheck makes it sound like something is really broken while
loading savegames, while it really is perfectly normal, as most
chunks do not implement LoadCheck.

Feature: framework to make savegames self-descriptive

We won't be able to make it fully self-descriptive (looking at you
MAP-chunks), but anything else can. With this framework, we can
add headers for each chunk explaining how each chunk looks like
in detail.

They also will all be tables, making it a lot easier to read in
external tooling, and opening the way to consider a database
(like SQLite) to use as savegame format.

Lastly, with the headers in the savegame, you can freely add
fields without needing a savegame version bump; older versions
of OpenTTD will simply ignore the new field. This also means
we can remove all the SLE_CONDNULL, as they are irrelevant.

The next few commits will start using this framework.

Codechange: mark chunks that are not stored as CH_READONLY

This makes it easier to spot chunks that have a save_proc that
is a nullptr, but also prevents confusion, where it looks like
the CH_ type of a chunk has influence on how it is being read.
It is not, it is only used for saving.

Codechange: add the ability to save/load a std::vector

std::vector<bool> is not possible, as .. that is a nice special
case in C++.

This new type will be used in next commit.

Change: prefix SL_ARR with the length of the array

This means that during loading we can validate that what is saved
is also that what is expected. Additionally, this makes all list
types similar to how they are stored on disk:
First a gamma to indicate length, followed by the data.
The size still depends on the type.

Codechange: make it more obvious SlArray supports SLE_VAR_NULL

In the end, the code was already doing the right thing, but a few
functions deep, and not really obvious. When validating what objects
can handle SLE_VAR_NULL, it is nicer to just have this obvious.

Codechange: use SL_NULL if you want to store null-bytes or load to nothing

Using SL_ARR for this gives us a bit of trouble later on, where we
add a length-field to SL_ARR. This of course is not the intention
of SLE_CONDNULL. So better seperate it.

Change: switch SL_DEQUE and SL_REFLIST length field to a gamma

The current SaveLoad is a bit inconsistent how long a length field
is. Sometimes it is a 32bit, sometimes a gamma. Make it consistent
across the board by making them all gammas.

Change: indicate in the savegame if a SL_STRUCT contains any data

This helps external tooling to understand if a SL_STRUCT should
be skipped when reading. Basically, this transforms an SL_STRUCT
into a SL_STRUCTLIST with either 0 or 1 length.

Change: store length of SL_STRUCTLIST in the savegame

This wasn't consistently done, and often variables were used that
were read by an earlier blob. By moving it next to the struct
itself, the code becomes a bit more self-contained and easier to
read.

Additionally, this allows for external tooling to know how many
structs to expect, instead of having to know where to find the
length-field or a hard-coded value that can change at any moment.

Codechange: remove the special station/vehicle code from SaveLoad

With the new SLEG_STRUCT it is much easier to embed a struct
in a struct, where the sub-struct has limitations on when it is
being used.
This makes both the code easier to read (less magic) and avoids
the SaveLoad needing to know all these things about Stations
and Vehicles.

Codechange: ability to store structs and list of structs in savegames

The commits following this will use this new functionality.

Currently, a few places do this manually. This has as drawback that
the Save() and Load() code need to be in sync, and that any change
can result in (old) savegames no longer loading. In general, it is
annoying code to maintain.

By putting everything in a description table, and use that for
both Save() and Load(), it becomes easier to see what is going on,
and hopefully less likely for people to make mistakes.

Codechange: rename SL_LST to SL_REFLIST to highlight the "reference" part

You can easily mistake SlList / SL_LST to be a list of SL_VAR, but
it is a list of SL_REF. With this rename, it hopefully saves a few
people from "wtf?" moments.

Codechange: refactor SlDequeueHelper to work with unsigned and be more generic

Future additions will start using it for std::list too.

Codechange: move GetVariableAddress inside SlObjectMember

Also move it to static, as nobody else is using it.

Codechange: make [Save|Load]Settings() behave more like other Save/Load code (#9335)

Prepare the full description and send it to SlObject. This does
require some code to be able to read to a SLE_VAR_NULL, like strings
etc, as there is no way to know their length beforehand.

Codechange: move SLF_NO_NETWORK_SYNC into settings

It is a settings-only flag, so don't pollute SaveLoad code with it.

Codechange: move SLF_NOT_IN_SAVE into settings

It is a settings-only flag, so don't pollute SaveLoad code with it.

Codechange: Remove FOR_ALL_CHUNK_HANDLERS

Co-Authored-By: Patric Stout <truebrain@openttd.org>

Codechange: use "[[maybe_unused]]" instead of a wide variety of other ways we had

While at it, replace OTTD_ASSERT with WITH_ASSERT, as this
is always set if assert() is valid. No matter if NDEBUG is set
or not.

Codechange: C++-ify lists for SaveLoad (#9323)

Basically, this changes "SaveLoad *" to either:
1) "SaveLoadTable" if a list of SaveLoads was meant
2) "SaveLoad &" if a single entry was meant

As added bonus, this removes SL_END / SLE_END / SLEG_END. This
also adds core/span.hpp, a "std::span"-lite.

Codechange: rename str_validate to StrMakeValid(InPlace) (#9304)

This to be more explicit the function changes the value, and not
returns yes/no.

Add: settings to limit your fast-forward game speed

By default this setting is set to 2500% normal game speed.

Codechange: move some DEBUG-levels and remove some others in saveload routine (#8474)

When running with -dsl=2 it is very easy to miss important information
as there was a lot of noise in between too. This tunes the debug
levels a bit to be less noisy while keeping the important bits.

Cleanup: Remove unused ChunkType flag CH_AUTO_LENGTH

CH_AUTO_LENGTH is no longer used anywhere, so remove all code
that depends on it.

Fix: next 67 savegame versions are used in PatchPacks; skip them (#8411)

Various of PatchPacks (Spring 2013, Joker, ChillPP) used versions
slightly higher than ours. Of course, as time went by, this
caught up with us, and we are now almost pushing a new version
that would conflict with them. To avoid users creating unneeded
issues about "why can I not load my savegame", lets be ahead of
the curve and flat-out refuse to load them.

Version-wise, this is totally fine. We have ~32k versions to go
before we run out (0x8000 is masked by JGRPP; we should avoid
using that). At the rate we bump savegames, this is not going to
happen in any sane reality.

Add: support for emscripten (play-OpenTTD-in-the-browser)

Emscripten compiles to WASM, which can be loaded via
HTML / JavaScript. This allows you to play OpenTTD inside a
browser.

Co-authored-by: milek7 <me@milek7.pl>

Fix #7925: Reset temporary saveload data at the start of loading a savegame instead of at the end.
Otherwise temporary data may be passed from an aborted load action to the next load action.

Remove: AutoFreeSmallVector.

The last use was for storing a list of memory blocks. As the way these lists are accessed is very
specific, it is easier to just write an explicit destructor instead of trying to exactly match the behaviour.

Codechange: Replace custom thread code with C++11 thread objects.

We assume a conforming C++11 compiler environment that has a valid <thread>-header.
Failure to run a real thread is handled gracefully.

Codechange: Use override specifer for overriding member declarations

This is a C++11 feature that allows the compiler to check that a virtual
member declaration overrides a base-class member with the same signature.

Also src/blitter/32bpp_anim_sse4.hpp +38 is no longer erroneously marked
as virtual despite being a template.

Codechange: liblzma is called liblzma, how ever strange that might be

It is the only library we use that calls itself with 'lib' in the
name. This might be confusing, but with the arrival of cmake a lot
of these things are automated. And detection will find 'liblzma',
not 'lzma', like with 'lzo', 'zlib', ..