[GSoC] Making vkernels checkpointable - week 6

[Pawel Dziepak]

Hello,

This week I have been working on saving and restoring terminal
configuration. Before freezing the vkernel termios parameters are
saved and then set again after thawing. Moreover, when the vkernel is
restored SIGWINCH is sent to the virtual processes controlling the
terminal what would cause them to redraw whatever has been drawn
before the checkpoint.

In addition to all this, I've continued my work on moving checkpoint
specific information in core dumps to ELF notes. The array of
ckpt_fileinfo structures has been moved to the ELF note of type
NT_DRAGONFLY_FILES. I've considered for a moment putting each
ckpt_fileinfo instance into another ELF note but the header overhead
would be too big and the benefits not worth it. The number of opened
files is stored in prpsinfo structure (i.e. NT_PRPSINFO).

Paweł