[PATCH] Core: use uppercase hexadecimal digits for percent-encoding

[Valentin V. Bartenev]

On Friday 27 June 2014 21:57:54 Maxim Dounin wrote:
> Hello!
> 
> On Thu, Jun 26, 2014 at 11:40:27PM -0700, Piotr Sikora wrote:
> 
> > # HG changeset patch
> > # User Piotr Sikora <piotr at cloudflare.com>
> > # Date 1403851163 25200
> > #      Thu Jun 26 23:39:23 2014 -0700
> > # Node ID 177382006b7d7a421688831d5793b2e417074b48
> > # Parent  42114bf12da0cf3d428d0e695139f5366cbd0513
> > Core: use uppercase hexadecimal digits for percent-encoding.
> > 
> > RFC3986 says that, for consistency, URI producers and normalizers
> > should use uppercase hexadecimal digits for all percent-encodings.
> > 
> > This is also what modern web browsers and other tools use.
> > 
> > Using lowercase hexadecimal digits makes it harder to interact with
> > those tools in case when use of the percent-encoded URI is required,
> > for example when $request_uri is part of the cache key.
> > 
> > Signed-off-by: Piotr Sikora <piotr at cloudflare.com>
> > 
> > diff -r 42114bf12da0 -r 177382006b7d src/core/ngx_string.c
> > --- a/src/core/ngx_string.c	Mon Jun 16 19:43:25 2014 +0400
> > +++ b/src/core/ngx_string.c	Thu Jun 26 23:39:23 2014 -0700
> > @@ -1407,7 +1407,7 @@ ngx_escape_uri(u_char *dst, u_char *src,
> >  {
> >      ngx_uint_t      n;
> >      uint32_t       *escape;
> > -    static u_char   hex[] = "0123456789abcdef";
> > +    static u_char   hex[] = "0123456789ABCDEF";
> >  
> >                      /* " ", "#", "%", "?", %00-%1F, %7F-%FF */
> 
> I can't say I like this change.  I've considered this a while ago, 
> and decided to keep it as is.  This preserve compatibility with 
> what nginx used to do for years.  And it also looks like Apache 
> does the same.
> 
> Any other opinions?
> 

I prefer to fix this instead of keeping it for another few years. 

Uppercase digits also look more distinctly, since all other parts
of path are usually in lowercase.

  wbr, Valentin V. Bartenev