libxml2: Wrong separator in XML_CATALOG_FILES?

libxml2: Wrong separator in XML_CATALOG_FILES?

[Hartmut Goebel]

[-- Attachment #1: Type: text/plain, Size: 553 bytes --]

Hi,

I just discovered that libxml2 sets the search-path-specification for
variable "XML_CATALOG_FILES" using space as separator, which is very
uncommon. The documentation for libxml2 does not state which separator
to use, while the docbook-tutorial [1] has an example using colons.

So I'm curious whether the space is correct.

[1] <http://tdg.docbook.org/tdg/5.0/appa.html>

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | h.goebel@crazy-compilers.com               |
| www.crazy-compilers.com | compilers which you thought are impossible |


[-- Attachment #2: 0xBF773B65.asc --]
[-- Type: application/pgp-keys, Size: 14855 bytes --]

Re: libxml2: Wrong separator in XML_CATALOG_FILES?

[Maxim Cournoyer]

Hello Hartmut,

On Tue, Apr 11, 2017 at 10:27 PM, Hartmut Goebel
<h.goebel@crazy-compilers.com> wrote:
>
> Hi,
>
> I just discovered that libxml2 sets the search-path-specification for
> variable "XML_CATALOG_FILES" using space as separator, which is very
> uncommon. The documentation for libxml2 does not state which separator
> to use, while the docbook-tutorial [1] has an example using colons.
>
> So I'm curious whether the space is correct.
>
> [1] <http://tdg.docbook.org/tdg/5.0/appa.html>

From my experiences with the udisks package, the XML_CATALOG_FILES
entries should be separated by space. I could find at least one source
which said it should be spaces [1], and another one suggested that
both the column and spaces should work, at least on Unix [2]. I guess
to get a definitive answer one would have to dive in the code of
libxml2.

I suggest we stick to what is known to work, i.e., using the space as
the separator for XML_CATALOG_FILES.

[1] Effective XML: 50 Specific Ways to Improve Your XML, by Elliotte
Rusty Harold (https://books.google.co.jp/books?id=GBT61nOT058C&pg=PA259&lpg=PA259&dq=xsltproc+XML+CATALOG+FILES+space+separated&source=bl&ots=UHr4NuXm1C&sig=9GgLW41OUmNOC9cRvyNyM6d3lYw&hl=en&sa=X&ved=0ahUKEwiq1tu2jp_TAhXCx7wKHazGDpMQ6AEIOTAD#v=onepage&q&f=false)

[2] Discussion on Gnome mailing list:
https://mail.gnome.org/archives/xml/2002-October/msg00028.html

Re: libxml2: Wrong separator in XML_CATALOG_FILES?

[Ludovic Courtès]

Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:

> Hello Hartmut,
>
> On Tue, Apr 11, 2017 at 10:27 PM, Hartmut Goebel
> <h.goebel@crazy-compilers.com> wrote:
>>
>> Hi,
>>
>> I just discovered that libxml2 sets the search-path-specification for
>> variable "XML_CATALOG_FILES" using space as separator, which is very
>> uncommon. The documentation for libxml2 does not state which separator
>> to use, while the docbook-tutorial [1] has an example using colons.
>>
>> So I'm curious whether the space is correct.
>>
>> [1] <http://tdg.docbook.org/tdg/5.0/appa.html>
>
> From my experiences with the udisks package, the XML_CATALOG_FILES
> entries should be separated by space.

Specifically, catalog.c in libxml2 has this:

	    /* the XML_CATALOG_FILES envvar is allowed to contain a
	       space-separated list of entries. */
	    cur = catalogs;
	    nextent = &catal->xml;
	    while (*cur != '\0') {
		while (xmlIsBlank_ch(*cur))
		    cur++;

Ludo’.

Re: libxml2: Wrong separator in XML_CATALOG_FILES?

[Maxim Cournoyer]

[-- Attachment #1: Type: text/plain, Size: 1222 bytes --]

Hi Ludovic,

ludo@gnu.org (Ludovic Courtès) writes:

> Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:
>
>> Hello Hartmut,
>>
>> On Tue, Apr 11, 2017 at 10:27 PM, Hartmut Goebel
>> <h.goebel@crazy-compilers.com> wrote:
>>>
>>> Hi,
>>>
>>> I just discovered that libxml2 sets the search-path-specification for
>>> variable "XML_CATALOG_FILES" using space as separator, which is very
>>> uncommon. The documentation for libxml2 does not state which separator
>>> to use, while the docbook-tutorial [1] has an example using colons.
>>>
>>> So I'm curious whether the space is correct.
>>>
>>> [1] <http://tdg.docbook.org/tdg/5.0/appa.html>
>>
>> From my experiences with the udisks package, the XML_CATALOG_FILES
>> entries should be separated by space.
>
> Specifically, catalog.c in libxml2 has this:
>
> 	    /* the XML_CATALOG_FILES envvar is allowed to contain a
> 	       space-separated list of entries. */
> 	    cur = catalogs;
> 	    nextent = &catal->xml;
> 	    while (*cur != '\0') {
> 		while (xmlIsBlank_ch(*cur))
> 		    cur++;
>
> Ludo’.

Thanks for digging this out for us! This will be a good reference for
when this question comes around next time!

Maxim

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]

Re: libxml2: Wrong separator in XML_CATALOG_FILES?

[Hartmut Goebel]

Am 13.04.2017 um 16:44 schrieb Ludovic Courtès:
> Specifically, catalog.c in libxml2 has this:
>
> 	    /* the XML_CATALOG_FILES envvar is allowed to contain a
> 	       space-separated list of entries. */

Thanks for digging into this. I'm still wondering about this
non-standard implementation, though.

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | h.goebel@crazy-compilers.com               |
| www.crazy-compilers.com | compilers which you thought are impossible |