[06/20] qobject: New qobject_from_vjsonf_nofail(), qdict_from_vjsonf_nofail()

Every printf()-like function sooner or later needs its vprintf()-like
buddy.  The next commit will need qobject_from_jsonf_nofail()'s buddy,
and qdict_from_jsonf_nofail()'s buddy will be used later in this
series.  Add both.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 include/qapi/qmp/qjson.h |  4 ++++
 qobject/qjson.c          | 44 +++++++++++++++++++++++++++++++++-------
 2 files changed, 41 insertions(+), 7 deletions(-)

On 07/12/2018 08:12 AM, Markus Armbruster wrote:
> Every printf()-like function sooner or later needs its vprintf()-like
> buddy.  The next commit will need qobject_from_jsonf_nofail()'s buddy,
> and qdict_from_jsonf_nofail()'s buddy will be used later in this
> series.  Add both.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---
>  include/qapi/qmp/qjson.h |  4 ++++
>  qobject/qjson.c          | 44 +++++++++++++++++++++++++++++++++-------
>  2 files changed, 41 insertions(+), 7 deletions(-)
> 
> diff --git a/include/qapi/qmp/qjson.h b/include/qapi/qmp/qjson.h
> index dc509d51ae..0db121bef9 100644
> --- a/include/qapi/qmp/qjson.h
> +++ b/include/qapi/qmp/qjson.h
> @@ -18,8 +18,12 @@ QObject *qobject_from_json(const char *string, Error **errp);
>  QObject *qobject_from_jsonv(const char *string, va_list *ap, Error **errp)
>      GCC_FMT_ATTR(1, 0);
>  
> +QObject *qobject_from_vjsonf_nofail(const char *string, va_list)

..., va_list ap)?

> +    GCC_FMT_ATTR(1, 0);
>  QObject *qobject_from_jsonf_nofail(const char *string, ...)
>      GCC_FMT_ATTR(1, 2);
> +QDict *qdict_from_vjsonf_nofail(const char *string, va_list ap)
> +    GCC_FMT_ATTR(1, 0);
>  QDict *qdict_from_jsonf_nofail(const char *string, ...)
>      GCC_FMT_ATTR(1, 2);
>  
> diff --git a/qobject/qjson.c b/qobject/qjson.c
> index 4a9dcff343..2e450231ff 100644
> --- a/qobject/qjson.c
> +++ b/qobject/qjson.c
> @@ -59,6 +59,25 @@ QObject *qobject_from_json(const char *string, Error **errp)
>      return qobject_from_jsonv(string, NULL, errp);
>  }
>  
> +/*
> + * Parse @string as JSON value with %-escapes interpolated.
> + * Abort on error.  Do not use with untrusted @string.
> + * Return the resulting QObject.  It is never null.
> + */
> +QObject *qobject_from_vjsonf_nofail(const char *string, va_list ap)
> +{
> +    va_list ap_copy;
> +    QObject *obj;
> +
> +    /* va_copy() is needed when va_list is an array type */
> +    va_copy(ap_copy, ap);
> +    obj = qobject_from_jsonv(string, &ap_copy, &error_abort);
> +    va_end(ap_copy);
> +
> +    assert(obj);
> +    return obj;
> +}
> +
>  /*
>   * Parse @string as JSON value with %-escapes interpolated.
>   * Abort on error.  Do not use with untrusted @string.
> @@ -70,13 +89,26 @@ QObject *qobject_from_jsonf_nofail(const char *string, ...)
>      va_list ap;
>  
>      va_start(ap, string);
> -    obj = qobject_from_jsonv(string, &ap, &error_abort);
> +    obj = qobject_from_vjsonf_nofail(string, ap);
>      va_end(ap);
>  
> -    assert(obj);
>      return obj;
>  }
>  
> +/*
> + * Parse @string as JSON object with %-escapes interpolated.
> + * Abort on error.  Do not use with untrusted @string.
> + * Return the resulting QDict.  It is never null.
> + */
> +QDict *qdict_from_vjsonf_nofail(const char *string, va_list ap)
> +{
> +    QDict *qdict;
> +
> +    qdict = qobject_to(QDict, qobject_from_vjsonf_nofail(string, ap));
> +    assert(qdict);
> +    return qdict;
> +}
> +
>  /*
>   * Parse @string as JSON object with %-escapes interpolated.
>   * Abort on error.  Do not use with untrusted @string.
> @@ -84,15 +116,13 @@ QObject *qobject_from_jsonf_nofail(const char *string, ...)
>   */
>  QDict *qdict_from_jsonf_nofail(const char *string, ...)
>  {
> -    QDict *obj;
> +    QDict *qdict;
>      va_list ap;
>  
>      va_start(ap, string);
> -    obj = qobject_to(QDict, qobject_from_jsonv(string, &ap, &error_abort));
> +    qdict = qdict_from_vjsonf_nofail(string, ap);
>      va_end(ap);
> -
> -    assert(obj);
> -    return obj;
> +    return qdict;
>  }
>  
>  typedef struct ToJsonIterState
> 

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>