Fellow Developers,
There have been more than a few cases when I have been working on memory
mapped devices that I have been a bit confused/annoyed by the semantics
of Packet::get() and Packet::set(). Currently, these two methods (which
are used pretty much everywhere we implement devices) assume that
devices are always of the same endianness as the host, i.e., they
perform a gtoh or htog endian conversion. This makes it very hard to
work with devices that are require a specific endianness.
I suspect the only reason things work at the moment is that we don't
really support anything other than little endian on little endian in
full system mode at the moment.
I'd like to change the get/set API to make endianness explicit.
Specifically, I'd like to add the following methods to Packet:
* getRaw() / setRaw() - Get data without conversion.
* getLE() / setLE() - Get data stored as little endian.
* getBE() / setBE() - Get data stored as big endian.
* get(ByteOrder) / set(value, ByteOrder) - For devices with
configurable byte order
The plan is to keep the old get & set methods but to flag them as
deprecated once all devices have been transitioned to the new interface.
Flagging the old interface as deprecated means that we'll be able to
slowly transition old code without breaking anything. However, old code
would still trigger non-fatal compiler warnings.
Any thoughts on this?
Thanks,
Andreas
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