This function is also supposed to check its given policy type with the
permission of the service itself. This implements the necessary
machinery to unstub these functions.
Policy::User seems to just be basic access (which is probably why vi:u
is restricted to that policy), while the other policy seems to be for
extended abilities regarding which displays can be managed and queried,
so this is assumed to be for a background compositor (which I've named,
appropriately, Policy::Compositor).
This didn't really provide much benefit here, especially since the
subsequent change requires that the behavior for each service's
GetDisplayService differs in a minor detail.
This also arguably makes the services nicer to read, since it gets rid
of an indirection in the class hierarchy.
The NVFlinger service is already passed into services that need to
guarantee its lifetime, so the BufferQueue instances will already live
as long as they're needed. Making them std::shared_ptr instances in this
case is unnecessary.
Like the previous changes made to the Display struct, this prepares the
Layer struct for changes to its interface. Given Layer will be given
more invariants in the future, we convert it into a class to better
signify that.
With the display and layer structures relocated to the vi service, we
can begin giving these a proper interface before beginning to properly
support the display types.
This converts the display struct into a class and provides it with the
necessary functions to preserve behavior within the NVFlinger class.
These are more closely related to the vi service as opposed to the
intermediary nvflinger.
This also places them in their relevant subfolder, as future changes to
these will likely result in subclassing to represent various displays
and services, as they're done within the service itself on hardware.
The reasoning for prefixing the display and layer source files is to
avoid potential clashing if two files with the same name are compiled
(e.g. if 'display.cpp/.h' or 'layer.cpp/.h' is added to another service
at any point), which MSVC will actually warn against. This prevents that
case from occurring.
This also presently coverts the std::array introduced within
f45c25aaba back to a std::vector to allow
the forward declaration of the Display type. Forward declaring a type
within a std::vector is allowed since the introduction of N4510
(http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4510.html) by
Zhihao Yuan.
Converts many of the Find* functions to return a std::optional<T> as
opposed to returning the raw return values directly. This allows
removing a few assertions and handles error cases like the service
itself does.
This appears to be a vestigial API function that's only kept around for
compatibility's sake, given the function only returns a success error
code and exits.
Since that's the case, we can remove the stubbed notification from the
log, since doing nothing is technically the correct behavior in this
case.
These values are not equivalent, based off RE. The internal value is put
into a lookup table with the following values:
[3, 0, 1, 2, 4]
So the values absolutely do not map 1:1 like the comment was indicating.
Avoids entangling the IPC buffer appending with the actual operation of
converting the scaling values over. This also inserts the proper error
handling for invalid scaling values.
This appears to only check if the scaling mode can actually be
handled, rather than actually setting the scaling mode for the layer.
This implements the same error handling performed on the passed in
values.
Within the actual service, it makes no distinguishing between docked and
undocked modes. This will always return the constants values reporting
1280x720 as the dimensions.
This IPC command is simply a stub inside the actual service itself, and
just returns a successful error code regardless of input. This is likely
only retained in the service interface to not break older code that relied
upon it succeeding in some way.
In many cases, we didn't bother to log out any of the popped data
members. This logs them out to the console within the logging call to
provide more contextual information.
Internally within the vi services, this is essentially all that
OpenDefaultDisplay does, so it's trivial to just do the same, and
forward the default display string into the function.
It appears that the two members indicate whether a display has a bounded
number of layers (and if set, the second member indicates the total
number of layers).
* get rid of boost::optional
* Remove optional references
* Use std::reference_wrapper for optional references
* Fix clang format
* Fix clang format part 2
* Adressed feedback
* Fix clang format and MacOS build
Previously, these were sitting outside of the Kernel namespace, which
doesn't really make sense, given they're related to the Thread class
which is within the Kernel namespace.
When a destructor isn't defaulted into a cpp file, it can cause the use
of forward declarations to seemingly fail to compile for non-obvious
reasons. It also allows inlining of the construction/destruction logic
all over the place where a constructor or destructor is invoked, which
can lead to code bloat. This isn't so much a worry here, given the
services won't be created and destroyed frequently.
The cause of the above mentioned non-obvious errors can be demonstrated
as follows:
------- Demonstrative example, if you know how the described error happens, skip forwards -------
Assume we have the following in the header, which we'll call "thing.h":
\#include <memory>
// Forward declaration. For example purposes, assume the definition
// of Object is in some header named "object.h"
class Object;
class Thing {
public:
// assume no constructors or destructors are specified here,
// or the constructors/destructors are defined as:
//
// Thing() = default;
// ~Thing() = default;
//
// ... Some interface member functions would be defined here
private:
std::shared_ptr<Object> obj;
};
If this header is included in a cpp file, (which we'll call "main.cpp"),
this will result in a compilation error, because even though no
destructor is specified, the destructor will still need to be generated by
the compiler because std::shared_ptr's destructor is *not* trivial (in
other words, it does something other than nothing), as std::shared_ptr's
destructor needs to do two things:
1. Decrement the shared reference count of the object being pointed to,
and if the reference count decrements to zero,
2. Free the Object instance's memory (aka deallocate the memory it's
pointing to).
And so the compiler generates the code for the destructor doing this inside main.cpp.
Now, keep in mind, the Object forward declaration is not a complete type. All it
does is tell the compiler "a type named Object exists" and allows us to
use the name in certain situations to avoid a header dependency. So the
compiler needs to generate destruction code for Object, but the compiler
doesn't know *how* to destruct it. A forward declaration doesn't tell
the compiler anything about Object's constructor or destructor. So, the
compiler will issue an error in this case because it's undefined
behavior to try and deallocate (or construct) an incomplete type and
std::shared_ptr and std::unique_ptr make sure this isn't the case
internally.
Now, if we had defaulted the destructor in "thing.cpp", where we also
include "object.h", this would never be an issue, as the destructor
would only have its code generated in one place, and it would be in a
place where the full class definition of Object would be visible to the
compiler.
---------------------- End example ----------------------------
Given these service classes are more than certainly going to change in
the future, this defaults the constructors and destructors into the
relevant cpp files to make the construction and destruction of all of
the services consistent and unlikely to run into cases where forward
declarations are indirectly causing compilation errors. It also has the
plus of avoiding the need to rebuild several services if destruction
logic changes, since it would only be necessary to recompile the single
cpp file.
Allows avoiding unnecessary copies of the vector depending on the
calling code.
While we're at it, remove a redundant no-parameter base constructor call
