Re: [Qemu-devel] [PATCH 4/6] QAPI: Introduce memchar_read QMP command

[Eric Blake <eblake@redhat.com>]

[-- Attachment #1: Type: text/plain, Size: 2113 bytes --]

On 08/22/2012 11:14 PM, Lei Li wrote:
> Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>

Again, subject line should use '-' not '_' for QMP.

> ---
>  hmp-commands.hx  |   16 ++++++++++++++++
>  hmp.c            |   15 +++++++++++++++
>  hmp.h            |    1 +
>  qapi-schema.json |   23 +++++++++++++++++++++++
>  qemu-char.c      |   32 ++++++++++++++++++++++++++++++++
>  qmp-commands.hx  |   31 +++++++++++++++++++++++++++++++
>  6 files changed, 118 insertions(+), 0 deletions(-)
> 
> diff --git a/hmp-commands.hx b/hmp-commands.hx
> index 829aea1..9f61633 100644
> --- a/hmp-commands.hx
> +++ b/hmp-commands.hx
> @@ -813,6 +813,22 @@ to memchr char device with size @var{size}.
>  ETEXI
>  
>      {
> +        .name       = "memchar-read",

while the HMP command should use '_' not '-'.

> +++ b/qapi-schema.json
> @@ -264,6 +264,29 @@
>             '*format': 'DataFormat'} }
>  
>  ##
> +# @memchar-read:
> +#
> +# Provide read interface for memchardev. Read from memchar
> +# char device and return the data.
> +#
> +# @chardev: the name of the  memchar char device.

Why two spaces?

> +#
> +# @size: the size to write in bytes.

s/write/read/

> +#
> +# @format: #optional the format of the data want to read from
> +#          memchardev, by default is 'utf8'.
> +#
> +# Returns: The data read from memchar as string.
> +#          If @chardev is not a valid memchr device, DeviceNotFound
> +#          If an I/O error occurs while reading, IOError
> +#
> +# Since: 1.2

1.3

> +##
> +{ 'command': 'memchar-read',
> +  'data': {'chardev': 'str', 'size': 'int', '*format': 'DataFormat'},
> +  'returns': 'str' }

While writing can default to UTF-8, I'm worried about reading - does
encoding in UTF-8 allow transmission of NUL bytes through JSON, or do
you have to use base64 to allow full binary data through?  What happens
if the data read includes a NUL byte that can't be encoded back into the
requested DataFormat?

-- 
Eric Blake   eblake@redhat.com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 620 bytes --]