This patch adds one API function to the QEMU plugin API

bool qemu_plugin_read_memory_vaddr(vaddr, GByteArray *, size_t);

The API allows reading memory from an arbitrary guest virtual
address, which is useful for many things but the motivating examples
are:

* Virtual Machine Introspection (VMI)
* Accurate and easier execution trace extraction
* Debugging and logging tools

An example of its use is added to the existing syscalls plugin,
which now has an option to hexdump the buf argument to any write(2)
syscalls which occur.

Rowan Hart (2):
  plugins: add plugin API to read guest memory
  plugins: add option to dump write argument to syscall plugin

 docs/about/emulation.rst     |  14 ++++-
 include/qemu/qemu-plugin.h   |  32 +++++++++-
 plugins/api.c                |  20 ++++++
 plugins/qemu-plugins.symbols |   1 +
 tests/tcg/plugins/syscall.c  | 117 +++++++++++++++++++++++++++++++++++
 5 files changed, 182 insertions(+), 2 deletions(-)

-- 
2.46.0