ACK: [PATCH] lib: fwts_json: fix output so that it is machine parsable (LP: #1902249)

[Alex Hung]

On 2020-11-20 3:32 p.m., Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
> 
> There is still an issue when escaped chars such as \n are being converted
> to a json string. Fix the escape char by converting the \n to \\ and n
> for the various escape chars.
> 
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>  src/lib/src/fwts_json.c | 27 +++++++++++++++++++++------
>  1 file changed, 21 insertions(+), 6 deletions(-)
> 
> diff --git a/src/lib/src/fwts_json.c b/src/lib/src/fwts_json.c
> index c92dd512..16735b95 100644
> --- a/src/lib/src/fwts_json.c
> +++ b/src/lib/src/fwts_json.c
> @@ -755,20 +755,30 @@ static char *str_indent(char *str, int indent)
>  	return str_append(str, buf);
>  }
>  
> -static bool char_escape(const int ch)
> +/*
> + *  char_escape()
> + *	convert escape char to the unescaped char to
> + *	be prefixed by \\.  If not an escape char, return 0
> + */
> +static inline int char_escape(const int ch)
>  {
>  	switch (ch) {
>  	case '"':
> +		return '"';
>  	case '\b':
> +		return 'b';
>  	case '\f':
> +		return 'f';
>  	case '\n':
> +		return 'n';
>  	case '\r':
> +		return 'r';
>  	case '\t':
> -		return true;
> +		return 't';
>  	default:
>  		break;
>  	}
> -	return false;
> +	return 0;
>  }
>  
>  static char *str_escape(char *oldstr)
> @@ -784,10 +794,15 @@ static char *str_escape(char *oldstr)
>  	if (!newstr)
>  		return NULL;
>  
> -	for (oldptr = oldstr, newptr = newstr; *oldptr; oldptr++, newptr++) {
> -		if (char_escape(*oldptr))
> +	for (oldptr = oldstr, newptr = newstr; *oldptr; oldptr++) {
> +		const int esc = char_escape(*oldptr);
> +
> +		if (esc) {
>  			*(newptr++) = '\\';
> -		*newptr = *oldptr;
> +			*(newptr++) = esc;
> +		} else {
> +			*(newptr++) = *oldptr;
> +		}
>  	}
>  	*newptr = '\0';
>  	return newstr;
> 


Acked-by: Alex Hung <alex.hung at canonical.com>