This series adds infrastructure which will be needed by the future monitor
protocol to handle and emit error information correctly.
QError is a QObject designed to stored error information in way that it can
be emitted by the protocol code or printed in an user friendly way.
To use it in the Monitor and its handlers, I've added a function called
qemu_error_structed(), which builds on top of Gerd's QemuErrorSink API, this
means that it is also capable of printing error information to stderr.
Basically, we have a QError member in the Monitor struct, which will be set
if an error has occurred. The Monitor's top level code will check it at
handler exit time and handle the error properly.
QError represents an error, and it has the following properties:
- Error code
- Error general description
- Error specific data
Code and description are stored in a static table in the QError module itself,
the error specific data is generated at error time by the function calling
qemu_error_structed().
This design is based on the way I plan to emit error information in the
protocol, which is:
{ "error": { "code": json-number,
"desc": json-string,
"data": json-value } "id": json-value, "timestamp": json-string }