Re: [Qemu-devel] [PATCH] json: Fix % handling when not interpolating

["Richard W.M. Jones" <rjones@redhat.com>]

On Wed, Jan 02, 2019 at 03:05:35PM +0100, Christophe Fergeau wrote:
> commit 8bca4613 added support for %% in json strings when interpolating,
> but in doing so, this broke handling of % when not interpolating as the
> '%' is skipped in both cases.
> This commit ensures we only try to handle %% when interpolating.
> 
> Signed-off-by: Christophe Fergeau <cfergeau@redhat.com>
> ---
>  qobject/json-parser.c | 10 ++++++----
>  tests/check-qjson.c   |  5 +++++
>  2 files changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/qobject/json-parser.c b/qobject/json-parser.c
> index 7a7ae9e8d1..d8eb210c0c 100644
> --- a/qobject/json-parser.c
> +++ b/qobject/json-parser.c
> @@ -208,11 +208,13 @@ static QString *parse_string(JSONParserContext *ctxt, JSONToken *token)
>              }
>              break;
>          case '%':
> -            if (ctxt->ap && ptr[1] != '%') {
> -                parse_error(ctxt, token, "can't interpolate into string");
> -                goto out;
> +            if (ctxt->ap) {
> +                if (ptr[1] != '%') {
> +                    parse_error(ctxt, token, "can't interpolate into string");
> +                    goto out;
> +                }
> +                ptr++;
>              }
> -            ptr++;
>              /* fall through */
>          default:
>              cp = mod_utf8_codepoint(ptr, 6, &end);
> diff --git a/tests/check-qjson.c b/tests/check-qjson.c
> index d876a7a96e..fa2afccb0a 100644
> --- a/tests/check-qjson.c
> +++ b/tests/check-qjson.c
> @@ -175,6 +175,11 @@ static void utf8_string(void)
>              "\xCE\xBA\xE1\xBD\xB9\xCF\x83\xCE\xBC\xCE\xB5",
>              "\xCE\xBA\xE1\xBD\xB9\xCF\x83\xCE\xBC\xCE\xB5",
>              "\\u03BA\\u1F79\\u03C3\\u03BC\\u03B5",
> +        },
> +            /* '%' character when not interpolating */
> +        {
> +            "100%",
> +            "100%",
>          },
>          /* 2  Boundary condition test cases */
>          /* 2.1  First possible sequence of a certain length */

Tested-by: Richard W.M. Jones <rjones@redhat.com>

as a fix for: https://bugzilla.redhat.com/show_bug.cgi?id=1668244#c3

Rich.

-- 
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