[Libguestfs] [PATCH 1/7] lib: Make pcre, libmagic and hivex libraries optional.

[Richard W.M. Jones]

On Thu, Nov 11, 2010 at 09:56:37AM +0000, Matthew Booth wrote:
> On 11/10/2010 11:45 AM, Richard W.M. Jones wrote:
> >>From a0b4caa0821b759de01361b7019c9c9c9607027d Mon Sep 17 00:00:00 2001
> >From: Richard Jones<rjones at redhat.com>
> >Date: Tue, 9 Nov 2010 15:59:40 +0000
> >Subject: [PATCH 1/7] lib: Make pcre, libmagic and hivex libraries optional.
> >
> >This change makes these libraries optional.  If they are not
> >available at compile time then certain core API features will
> >be disabled (see below).
> >
> >This also changes PCRE detection to use pkg-config instead
> >of the ad hoc autoconf checks.
> >
> >The large inspect.c file has been split out into separate
> >function-specific files.
> >
> >   file-architecture: requires pcre&  libmagic
> >   inspection: requires pcre&  hivex
> >---
> >  README                 |    4 +-
> >  configure.ac           |   45 ++--
> >  po/POTFILES.in         |    2 +
> >  src/Makefile.am        |    6 +-
> >  src/filearch.c         |  267 +++++++++++++++++++++
> >  src/guestfs-internal.h |   16 ++
> >  src/guestfs.c          |    9 +
> >  src/inspect.c          |  607 +++++++++++++++---------------------------------
> >  src/listfs.c           |  169 ++++++++++++++
> >  9 files changed, 674 insertions(+), 451 deletions(-)
> >  create mode 100644 src/filearch.c
> >  create mode 100644 src/listfs.c
> 
> What's the use case here? Embedded systems running libguestfs?
> Doesn't seem likely. If nobody is actually likely to build
> libguestfs this way, this only seems to complicate the build system
> further in ways which will be rarely tested.
> 
> Splitting inspect in 2 isn't a bad idea, though.

I think it's better to view this patch as a cleanup of the configure
script.  Making hivex optional I think is a good idea, and once you've
done that, it's a cleanup to make the other 2 libraries (+ libvirt &
libxml2 in later patch) use the same style of configure test.

Having said that, I did test this with each library both installed and
removed.

Rich.

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