Adds support for a --deterministic command-line option that makes
repeated runs the same:
- Keyboard and mouse input is ignored
- The sound server does a periodic pull from the DMA channel (so that
it gets drained), but only does so via a periodic timer (instead of
being driven by a cubeb callback, which could arrive at different
times)
- Disk image writes are disabled (reads of a modified area still
work via an in-memory copy)
- NVRAM writes are disabled
- The current time that ViaCuda initializes the guest OS is always the
same.
This makes execution exactly the same each time, which should
make debugging of more subtle issues easier.
To validate that the deterministic mode is working, I've added a
periodic log of the current "time" (measured in cycle count), PC
and opcode. When comparing two runs with --log-no-uptime, the generated
log files are identical.
There are cases where when it's necessary (e.g. given uninitialized NVRAM,
the Beige G3 with the 10.2 install CD inserted will update the boot
device and restart to boot from it).
Restart support was done by wrapping the ppc_exec function in a loop and
checking for a restart power off reason. We also need to disconnect all
event listeners, since they will be recreated when the machine is
re-initialized.
