[PATCH v3] bootstrap: Allow perl modules in $buildreq

[Martin Kletzander]

With this patch it is possible to put e.g. "perl::XML:XPath -" in
$buildreq in bootstrap.conf which will cause a check for perl module
XML::XPath using:

  perl -m"XML::XPath" -e 'exit 0' >/dev/null 2>&1

If this fails due to any other error then XML::XPath missing, it is left
on the user to fix up his/hers bootstrap.conf.  One of the examples
might be perl itself missing, which should be in $buildreq and precede
any perl::Module specifications.  Versioning of perl modules is not
supported.

Signed-off-by: Martin Kletzander <address@hidden>
---

Notes:
    v3:
     - Actually use $PERL
     - s/Check for perl modules/Extract module name/ in comment to
       de-duplicate redundant info
    
    v2:
     - Fix typo s/per::/perl::/
     - Honour $PERL if it exists

 build-aux/bootstrap | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/build-aux/bootstrap b/build-aux/bootstrap
index 4f0493a..e0c4ec2 100755
--- a/build-aux/bootstrap
+++ b/build-aux/bootstrap
@@ -1,6 +1,6 @@
 #! /bin/sh
 # Print a version string.
-scriptversion=2013-12-05.23; # UTC
+scriptversion=2014-12-08.12; # UTC

 # Bootstrap this package from checked-out sources.

@@ -42,6 +42,9 @@ export LC_ALL

 local_gl_dir=gl

+# Honour $PERL, but work even if there is none
+PERL="${PERL-perl}"
+
 me=$0

 usage() {
@@ -456,6 +459,7 @@ check_versions() {
     test "$appvar" = TAR && appvar=AMTAR
     case $appvar in
         GZIP) ;; # Do not use $GZIP:  it contains gzip options.
+        PERL::*) ;; # Keep perl modules as-is
         *) eval "app=\${$appvar-$app}" ;;
     esac

@@ -473,6 +477,17 @@ check_versions() {
           ret=1
           continue
         } ;;
+      # Another check is for perl modules.  These can be written as
+      # e.g. perl::XML::XPath in case of XML::XPath module, etc.
+      perl::*)
+        # Extract module name
+        app="${app#perl::}"
+        if ! $PERL -m"$app" -e 'exit 0' >/dev/null 2>&1; then
+          warn_ "Error: perl module '$app' not found"
+          ret=1
+        fi
+        continue
+        ;;
     esac
     if [ "$req_ver" = "-" ]; then
       # Merely require app to exist; not all prereq apps are well-behaved
-- 
2.2.0