This allows us to 'nest' firmware formats, and removes a ton of duplication.
The aim here is to deprecate FuFirmwareImage -- it's almost always acting
as a 'child' FuFirmware instance, and even copies most of the vfuncs to allow
custom types. If I'm struggling to work out what should be a FuFirmware and
what should be a FuFirmwareImage then a plugin author has no hope.
For simple payloads we were adding bytes into an image and then the image into
a firmware. This gets really messy when most plugins are treating the FuFirmware
*as* the binary firmware file.
The GBytes saved in the FuFirmware would be considered the payload with the
aim of not using FuFirmwareImage in the single-image case.
Devices may want to support more than one protocol, and for some devices
(e.g. Unifying peripherals stuck in bootloader mode) you might not even be able
to query for the correct protocol anyway.
This allows us to check that the plugin is writing into a mutable buffer. Also
fix up the plugins that are currently 'wrong' and use the new function for the
plugins doing the right thing.
At the moment FuChunks are sometimes mutable, and sometimes immutable, and it's
all a bit too low level for comfort.
Before we can do any kind of optimisation or verification we need plugins to
stop reading directly from the C structure. The aim here is to make FuChunk
optionally mutable without making assumptions about the memory model, and also
to be able to introspect it for the docs.
The end year is legally and functionally redundant, and more importantly causes
cherry-pick conflicts when trying to maintain old branches. Use git for history.
Conceptually we were trying to stuff subtly different actions into one vfunc:
* Read firmware from the device to update the verification checksums
* Read a firmware blob from the device for debugging
For the first action we might want to mask out the sections of the flash with
serial numbers (so the verification hashes match the ones published on the LVFS)
and for the second we want just a raw ROM file from the hardware with no
pre-processing that we can compare against an external SPI dumper.
Split out ->dump_firmware to get the raw blob, and allow plugins to also
implement ->read_firmware() if they have to mask out specific offsets or remove
specific images from the FuFirmware container.
In the common case when masking is not required, fall back to using a 'binary'
FuFirmware automatically to make most plugins simpler.
If we say that the version format should be the same for the `version_lowest`
and the `version_bootloader` then it does not always make sense to set it at
the same time.
Moving the `version_format` to a standalone first-class property also means it
can be typically be set in the custom device `_init()` function, which means we
don't need to worry about *changing* ther version format as set by the USB and
UDev superclass helpers.