Re: [Qemu-devel] [PATCH 01/11] QMP: Introduce specification file

[Avi Kivity <avi@redhat.com>]

On 06/26/2009 06:02 PM, Anthony Liguori wrote:
> # v1 ->  v2
> #  o allow integer in symbol names (C-style)
> #  o allow negative integer/floats
> #  o no newlines in strings
> #  o one value per response_data line
>
> __skip__: [ \t]+
>
> symbol: [A-Za-z_\-][A-Za-z_\-0-9]*
>
> decimalinteger: (-)?[1-9][0-9]+
>    
>

Traditionally, 0 is recognized as an integer.

> hexinteger: 0x[0-9]+
>    

[a-fA-f]

> float: (-)?[0-9]+\.[0-9]+
>    

5, 3., .10, 1e9 are all floats.

> string: \"([^\"\\\n]|(\\[0-9][0-9][0-9]))*\" | symbol
>    

I think json recognises 'blah' but not symbol.  Also it may recognize 
other escapes.

It's important to allow clients to use json emitters so they can 
construct a dict and throw it at qemu, similarly to parse qemu results.

> arg_list: value arg_list?
>
> command: symbol arg_list? '\n'
>    

Better to use a dictionary for the argument list (more self-documenting, 
easier expansion).

I'd also adopt jsonrpc's request and id attributes, they allow async 
commands and remove the need for any specialized parsing.

> response_status: ('+' | '-') number string? '\n'
> response_data: '=' value '\n'
> async_msg: '*' arg_list '\n'
>
>    

Similarly, return a value that contains message type, id, and return value.

I think it's fine to drop jsonrpc as the standard (but retain its 
features) and just adopt json for encoding.

-- 
error compiling committee.c: too many arguments to function