Re: CVS update: subversion/subversion/libsvn_delta xml_output.c

Greg Hudson wrote:

> >> prop-delta elements do not contain meaningful pcdata, just set and
> >> delete elements.
>
> > ?? From day 1, the spec has always defined the "value" of a
> > prop-delta `set' command to be the pcdata inside the tag.

This reminds me: one addendum to my previous encoding note.

The "value == pcdata" rule has to go. The value needs to be encoded as a
pair. The first element of the pair identifies the encoding of the
second. You want to store as much as possible in the clear, so you want
to use straight PCDATA wherever possible, but this means that at the
very least there are two encodings:

    0 PCDATA
    1 BASE16

I suggest:

<propvalue>
   <encoding>1</encoding>
    <value> .... PCDATA or base16 </value>
</propvalue>

Unless the type of the property already gives the encoding, you need to
do something of this sort. Even if it does, I suggest that a little bit
of redundant encoding here is worthwhile in case somebody buggers a
property name by mistake. Including the encoding type won't change the
compressability of the XML by more than a few bits if the XML isn't in
indented form.

shap
Received on Sat Oct 21 14:36:12 2006