Previously these functions were declared without the static specifier,
giving them external linkage, which isn't really ideal.
Instead, we can place these functions up by the relevant file-scope
variables and place them inside an anonymous namespace with said variables,
giving them internal linkage.
Now that the std::map less-than comparitor is capable of being used with
heterogenous lookup, we're able to convert many of the querying
functions that took std::string references over to std::string_view.
Now these functions may be used without potentially allocating a
std::string instance unnecessarily.
Previously, when performing find() operations or indexing operations on
the section map, it would need to operate on a std::string key.
This means cases like:
map.find(some_string_view)
aren't usable, which kind of sucks, especially given for most cases, we
use regular string literals to perform operations in calling code.
However, since C++14, it's possible to use heterogenous lookup to avoid
needing to construct exact key types. In otherwords, we can perform the
above or use string literals without constructing a std::string instance
around them implicitly.
We simply need to specify a member type within our comparison struct
named is_transparent, to allow std::map to perform automatic type
deduction.
We also slightly alter the algorithm to an equivalent compatible with
std::string_view (which need not be null-terminated), as strcasecmp
requires null-terminated strings.
While we're at it, we can also provide a helper function to the struct
for comparing string equality rather than only less than. This allows
removing other usages of strcasecmp in other functions, allowing for the
transition of them to std::string_view.
fmt diverges from printf in that '.' as a precision specifier may only
be used for floating-point values (makes sense, given it's indicating
precision after the decimal point).
Begins the transition to using fmt for string formatting where
applicable. Given fmt supports formatting std::string instances out of
the box, we can remove now-unnecessary calls to .c_str() and .data().
Note that this change does not touch the actual logging subsystem aside
from converting the final StringFromFormat call in the process over to
fmt::format. Given our logging system is heavily used throughout the
entire codebase, and converting that over will be quite a large change
by itself, this will be tackled near the end of the conversion process.
Avoids dragging in IniFile, EXI device and SI device headers in this header which is
quite widely used throughout the codebase.
This also uncovered a few cases where indirect inclusions were being
relied upon, which this also fixes.
Allows for both string types to be non-allocating. We can't remove the
const char* overload in this case due to the fact that pointers can
implicitly convert to bool, so if we removed the overload all const
char arrays passed in would begin executing the bool overload instead of
the string_view overload, which is definitely not what we want to occur.
Since C++17, non-member std::size() is present in the standard library
which also operates on regular C arrays. Given that, we can just replace
usages of ArraySize with that where applicable.
In many cases, we can just change the actual C array ArraySize() was
called on into a std::array and just use its .size() member function
instead.
In some other cases, we can collapse the loops they were used in, into a
ranged-for loop, eliminating the need for en explicit bounds query.
std::call_once is guaranteed to execute the given callable object
exactly once. This guarantee holds even if the function is called
concurrently from several threads.
Given that, we can replace the mutex and boolean flag with
std::call_once and a std::once_flag to perform the same behavior.
Previously, every entry pair within the map would be copied. The reason
for this is subtle.
A std::map's internal entry type is defined as:
std::pair<const Key, Value>
but the loop was declaring it as:
std::pair<Key, Value>
These two types aren't synonymous with one another and so the compiler
is required to always perform a copy.
Using structured bindings avoids this (as would plain auto or correcting
the explicit type), while also allowing the use of more appropriate
names compared to first and second.
std::function is allowed to heap allocate in order to hold any necessary
bound data in order to execute properly (e.g. lambdas with captures), so
this avoids unnecessary reallocating.
While current usages of ParseLine aren't problematic, this is still a
public function that can be used for other purposes. Essentially makes
the function handle potential external inputs a little nicer.
We can just utilize map's insert_or_assign() function and check the
return value to determine whether or not we need to insert the key into
the keys_order vector.
Anthony