Re: [naviserver-devel] whole lotta errors

[Stephen D. <sd...@gm...>]

On 8/20/06, Zoran Vasiljevic <zv...@ar...> wrote:
>
> On 15.08.2006, at 21:09, Stephen Deasey wrote:
> > * is checking for bytearray type a good way to handle binary Tcl
> > objects?
>
> Hm... how would you (generally) check for a byte-array?
> You can get a byte-array from object but you can't
> (without looking into the object type which is really not
> something that is portable) say which type of object you
> are dealing with.


Sure you can:

  byteArrayTypePtr = Tcl_GetObjType("bytearray");

  if (objPtr->typePtr == byteArrayTypePtr) {
      /* It's a bute array... */
  }


> I believe the main source of problem here is somebody
> slurping the whole file and wanting to return that file
> as-is i.e. w/o any translations. In that case, he/she
> cound use [ns_conn encoding] to set the encoding of the
> connection before calling ns_return. This way we can
> strip away all the extra options from the content-returning
> commands and request the writer to use ns_conn to set
> the correct encoding OR to skip encoding altogether
> (for example: ns_conn encoding binary).
> Wouldn't that make sense?


I was thinking more of the case where you dynamically create a binary
object, like a 'captcha' image.  You want to ns_return it and have the
server do the right thing without having to fiddle with a -binary
switch.

Another place where checking for a byte array might be good is the
caching code.  when you cache an object, it first gets converted to a
valid utf-8 rep.  When you get the object out of the cache, if you
treat it as a byte array, evrything still works -- the conversion from
byte array to utf-8 string and back again is non lossy. It's just non
optimal.

As we're starting to see things like the -binary switch spread, I was
wondering if it was, in general, a good idea to check for byte arrays
and have things work transparently. Are there any gotchas?