BIND 10 #2448: configure.ac missing checks for --enable-generate-docs

[BIND 10 Development]

#2448: configure.ac missing checks for --enable-generate-docs
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            Reporter:  jelte         |                        Owner:
                Type:  task          |  UnAssigned
            Priority:  medium        |                       Status:  new
           Component:  build system  |                    Milestone:  New
           Sensitive:  0             |  Tasks
         Sub-Project:  Core          |                     Keywords:
Estimated Difficulty:  0             |              Defect Severity:  N/A
         Total Hours:  0             |  Feature Depending on Ticket:
                                     |          Add Hours to Ticket:  0
                                     |                    Internal?:  0
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 This is really mostly only relevant for devs updating documentation, but
 the configure checks done when doing --enable-generate-docs have some room
 for improvement:

 on debian, if you do --enable-generate-docs, but don't have the 'xmlto'
 package installed, you get a rather cryptic error (I had only installed
 docbook and xsltproc initially):

 {{{
 checking for xsltproc... /usr/bin/xsltproc
 checking if /usr/bin/xsltproc works... I/O error : Attempt to load network
 entity
 http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl
 warning: failed to load external entity
 "http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl"
 cannot parse
 http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl
 configure: error: "Error with /usr/bin/xsltproc using
 release/xsl/current/manpages/docbook.xsl"
 }}}

 Also, elinks is needed in the build process

 we probably want a few checks for both of these in configure.ac :)

-- 
Ticket URL: <http://bind10.isc.org/ticket/2448>
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BIND 10 Development