This commit changes how the objects in OpenThread access each other.
It adds a template `Get<Type>()` method in `InstanceLocator`. This
method returns a reference to a given `Type` object belonging to the
OpenThread instance (e.g. `Get<MeshForwarder>()` returns a reference
to `MeshForwarder` object on the OpenThread instance). The
`InstanceLocator` is used as base class of all OpenThread classes so
every class can easily access any other object. This commit also
changes how the main instance is retrieved in `InstanceLocator` for
the single-instance case. The method `GetInstance()` directly uses the
raw buffer `gInstanceRaw`. This change helps make the `GetInstance()`
and in turn all `Get<Type>()` methods in-line. This commit also
removes the existing getters across all classes to use the new
`Get<Type>()` model.
This commit makes the following changes: It defines the public
`otInstance` as an empty opaque structure which is used by all public
C OpenThread APIs. It defines a new class `ot::Instance` (inheriting
from `otInstance) which is then used in core source files. The
functionality related to the instance is also moved/added into the
newly added `Instance` class (as class/static or member methods).
This commit new configuration option `enable-multiple-instances` and
its corresponding option `OPENTHREAD_ENABLE_MULTIPLE_INSTANCES`. When
enabled OpenThread supports handling of multiple instances. By default
this is disabled.
This commit also adds two optimizations for single instance case to
simplify the code and also help reduce memory/RAM usage:
(1) OpenThread objects/classes typically keep a reference to a higher
level object (e.g., many classes keep track of owning `ThreadNetif`)
to be able to access other objects/methods within OpenThread class
hierarchy. In single instance mode, the reference member variables are
removed and instead global functions are used to access the singleton
objects from one class to the other. To implement this, a group of
`<Object>Locator` classes are defined (e.g., `ThreadNetifLocator`,
etc.) which are then used as base class of other OpenThread classes.
(2) OpenThread objects which provide a callback/handler (e.g.,
`Timer`, `Tasklet`, etc.) have `void *mContext` member variable which
is used to keep track of the owner of the object. In single instance
mode the `mConext` member variables are removed since the owner is
expected to be a singleton and can be uniquely determined from the
callback function.
To implement this, two changes are made: First the handler methods are
modified to provide a reference to the object (e.g., `Timer` handler
will provide a `Timer &aTimer` as a parameter of its handler
callback). Second, a new base class `Context` is introduced which
hides the implementation providing an arbitrary context information. A
new static method `GetOwner(aContext)` is added to classes which own a
callback providing objects. This method help convert a `Context` to
the reference of the owner class object.
* Add diagnostics module in OpenThread
- provide the same diagnostics interface for both CLI and NCP usage
- implement common diagnostics features based on existing platform interface defined in 'include/platform/'
- other more platform specific diagnostics features will be processed under platform layer
- update CLI interface to support diagnostics feature
- update both Posix and CC2538 platform to support diagnostics feature
* Add diagnostics module unit test
- move platform.h from "examples/platform" to "include/platform"
- add test_diag.cpp to test diagnostics module
* Add a configuration option that would enable/disable diagnostics module
Add --enable-diag configuration option to enable/disable diagnostics module when building OpenThread.