Re: [PATCH 02/13] plugins/api: added a boolean parsing plugin api

["Alex Bennée" <alex.bennee@linaro.org>]

Mahmoud Mandour <ma.mandourr@gmail.com> writes:

> This call will help boolean argument parsing since arguments are now
> passed to plugins as a name and value.
>
> Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
> ---
>  include/qemu/qemu-plugin.h | 13 +++++++++++++
>  plugins/api.c              |  5 +++++
>  2 files changed, 18 insertions(+)
>
> diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
> index dc3496f36c..7d0b23c659 100644
> --- a/include/qemu/qemu-plugin.h
> +++ b/include/qemu/qemu-plugin.h
> @@ -564,4 +564,17 @@ int qemu_plugin_n_max_vcpus(void);
>   */
>  void qemu_plugin_outs(const char *string);
>  
> +/**
> + * qemu_plugin_bool_parse() - parses a boolean argument in the form of
> + * "<argname>=[on|yes|true|off|no|false]"
> + *
> + * @name: argument name, the part before the equals sign
> + * @val: argument value, what's after the equals sign
> + * @ret: output return value
> + *
> + * returns true if the combination @name=@val parses correctly to a boolean
> + * argument, and false otherwise
> + */
> +bool qemu_plugin_bool_parse(const char *name, const char *val, bool *ret);
> +
>  #endif /* QEMU_PLUGIN_API_H */
> diff --git a/plugins/api.c b/plugins/api.c
> index 332e2c60e2..43e239f377 100644
> --- a/plugins/api.c
> +++ b/plugins/api.c
> @@ -383,3 +383,8 @@ void qemu_plugin_outs(const char *string)
>  {
>      qemu_log_mask(CPU_LOG_PLUGIN, "%s", string);
>  }
> +
> +bool qemu_plugin_bool_parse(const char *name, const char *value, bool *ret)
> +{
> +    return qapi_bool_parse(name, value, ret, NULL);
> +}

I'm not sure we want to have such a naive pass through of
qapi_bool_parse here. For one thing I think all the current call sites
guarantee value will be set to something. I think that's still the case
for args we supply to plugin_init because of our pre-processing but the
plugin user could at any point decide to parse a random string pair with
it.

We should check for name/value being non-NULL before the pass through I
think.

-- 
Alex Bennée