[PATCH RFC V2 00/10] xl/libxl: JSON infrastructure and new "xl-json" format

[Wei Liu <wei.liu2@citrix.com>]

This series contains my original patches to add in JSON parser and a new patch
to add "xl-json" format. The last patch makes use of JSON parser.

For the JSON parser (taken from my previous email):

Libxl introduced JSON infrastructure to communicate with upstream QEMU. The
ability of exisiting JSON infrastructure is to convert libxl_FOO struct to
libxl JSON object and parse JSON object (string) returned by QEMU.

This series makes libxl able to convert a JSON string to libxl_FOO struct.
The conversion is done in two macro steps:
 1. convert JSON string to libxl JSON object (libxl__json_object)
 2. convert libxl JSON object to libxl_FOO struct

The first stage is done with existing infrastructure. This series focuses on
the second stage.

To break things down:
 * Patch 1 is only mechanical change
 * Patch 2, 3, 4 and 6 are changes to generic libxl JSON infrastructure
 * Patch 5 introduces parser functions for builtin types
 * Patch 7 and 8 are changes to code generator
 * Patch 9 contains changes to test code generator

Now we have the ability to do the following transformation:
  libxl_FOO struct -> libxl_FOO JSON object -> libxl JSON internal object ->
  libxl_FOO struct

This full cycle can be used to preserved runtime configurations of a domain.

Patch 10 makes use of the new parser and introduces "xl-json" format. Please
refer to commit log for details. It would be good if I can get some input on
this new format and it's usage. Currently it's restricted to internal use only,
that is, user is not allowed to supply a config file in JSON format.

It would be good if we can get this kind of infrastructure change through the
push gate before pursing next step ("pull runtime information for a domain").

Wei.

Changes in V2:
* address IanC's comments on JSON parser
* add "xl-json" format patch

Wei Liu (10):
  libxl IDL: rename json_fn to json_gen_fn
  libxl_json: introduce libx__object_from_json
  libxl_internal: make JSON_* types bit-field
  libxl_internal: introduce libxl__json_object_is_{null,number,double}
  libxl_json: introduce parser functions for builtin types
  libxl_json: allow basic JSON type objects generation
  libxl/gentypes.py: generate JSON object for keyed-union discriminator
  libxl IDL: generate code to parse libxl__json_object to libxl_FOO
    struct
  libxl/gentest.py: test JSON parser
  xl: introduce "xl-json" format

 docs/man/xl.cfg.pod.5                |    2 +-
 tools/libxl/gentest.py               |   27 +++-
 tools/libxl/gentypes.py              |  119 ++++++++++++++-
 tools/libxl/idl.py                   |   23 ++-
 tools/libxl/libxl.h                  |    1 +
 tools/libxl/libxl_cpuid.c            |   92 +++++++++---
 tools/libxl/libxl_internal.h         |   39 +++--
 tools/libxl/libxl_json.c             |  263 ++++++++++++++++++++++++++++++++--
 tools/libxl/libxl_json.h             |   27 +++-
 tools/libxl/libxl_nocpuid.c          |    7 +
 tools/libxl/libxl_types.idl          |   31 ++--
 tools/libxl/libxl_types_internal.idl |    4 +-
 tools/libxl/xl_cmdimpl.c             |  103 ++++++++++---
 13 files changed, 649 insertions(+), 89 deletions(-)

-- 
1.7.10.4