On Fri, 17 Jun 2022 12:25:04 +0100 Bruce Richardson <bruce.richard...@intel.com> wrote:
> On Fri, Jun 17, 2022 at 01:16:08PM +0200, Morten Brørup wrote: > > > From: Chengwen Feng [mailto:fengcheng...@huawei.com] > > > Sent: Friday, 17 June 2022 11.46 > > > > > > This patch supports escape special characters (including: \",\\,/,\b, > > > /f,/n,/r,/t) when telemetry string. > > > This patch is used to support telemetry xxx-dump commands which the > > > string may include special characters. > > > > > > Signed-off-by: Chengwen Feng <fengcheng...@huawei.com> > > > --- > > > lib/telemetry/telemetry.c | 96 +++++++++++++++++++++++++++++++++++++-- > > > 1 file changed, 93 insertions(+), 3 deletions(-) > > > > > > diff --git a/lib/telemetry/telemetry.c b/lib/telemetry/telemetry.c > > > index c6fd03a5ab..0f762f633e 100644 > > > --- a/lib/telemetry/telemetry.c > > > +++ b/lib/telemetry/telemetry.c > > > @@ -215,6 +215,94 @@ container_to_json(const struct rte_tel_data *d, > > > char *out_buf, size_t buf_len) > > > return used; > > > } > > > > > > +static bool > > > +json_is_special_char(char ch) > > > +{ > > > + static unsigned char is_spec[256] = { 0 }; > > > + static bool init_once; > > > + > > > + if (!init_once) { > > > + is_spec['\"'] = 1; > > > + is_spec['\\'] = 1; > > > + is_spec['/'] = 1; > > > + is_spec['\b'] = 1; > > > + is_spec['\f'] = 1; > > > + is_spec['\n'] = 1; > > > + is_spec['\r'] = 1; > > > + is_spec['\t'] = 1; > > > + init_once = true; > > > + } > > > + > > > + return (bool)is_spec[(unsigned char)ch]; > > > +} > > According to the json spec at [1], the characters that need to be escaped > are: > a) any characters <0x20 > b) inverted commas/quote character \" > c) the "reverse solidus character", better known to you and I as the > back-slash. > > Therefore, I think this table generation could be simplified, but also > expanded using this. For completeness we should also see about handling all > control characters if they are encountered. > > [1] https://www.rfc-editor.org/rfc/rfc8259.txt > > /Bruce Since it is trivial could be initializer? static const uint8_t is_spec[256] = { [0 ... 0x20] = 1, ['\"' ] = 1, ['\\' ] = 1, ['/'] = 1, etc Or we could change the telemetry API to disallow control characters?
