buildconf: allow configuration without APR sources

Previously we required copying the APR (and APR-util) source code into
srclib or some other location on disk in order to build httpd directly
from source. This is annoying if you're on a distribution that already
has the required files in its APR dev packages.

Practically speaking, if you're not building an official distribution
tarball, you only need the following files:

1) config.guess
2) config.sub
3) find_apr.m4
4) find_apu.m4
5) PrintPath

1 and 2 come from automake. 3 and 4 are included in some distributions'
(e.g. Debian's) development packages for APR/-util. That leaves
PrintPath, which has not changed meaningfully in over a decade and is
checked in completely here.

Passing an apr-config executable to buildconf's --with-apr option will
now enable a mode in which the above files (minus PrintPath) are copied
from their respective homes, removing the need for APR sources on disk.
Otherwise, if a source tree is passed, the current behavior is retained
and all of the above files are copied from APR directly.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/trunk-buildconf-noapr@1780441 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 60 insertions, 13 deletions

diff --git a/buildconf b/buildconf
index 38969681ee..01c1c60d30 100755
--- a/buildconf
+++ b/buildconf
@@ -61,10 +61,12 @@ do
 done
 
 #
-# Check to be sure that we have the srclib dependencies checked-out
+# Check to be sure that we have the srclib dependencies checked-out, or that a
+# working apr-config installation has been specified.
 #
 
 should_exit=0
+apr_config=         # path to apr-config (empty if using a source directory)
 apr_found=0
 apu_found=0
 apr_major_version=2
@@ -76,6 +78,25 @@ do
         apr_src_dir=$dir
         apr_found=1
         break
+    elif which "${dir}" >/dev/null 2>&1; then
+        # We're using apr-config. Do a sanity check.
+        apr_config=`which "${dir}"`
+        echo "testing apr-config executable: ${apr_config}"
+
+        version=`"${apr_config}" --version`
+        version=`echo "${version}" | sed -n '/^[0-9][0-9]*\.[0-9][0-9]*\.[0-9][0-9]*$/p'`
+
+        if [ -z "${version}" ]; then
+            echo "apr-config gave us an invalid --version"
+            apr_config=
+            continue
+        fi
+
+        echo "using apr-config version ${version}"
+        apr_major_version=${version} # we'll make a real "major version" later
+        apr_src_dir=`"${apr_config}" --installbuilddir`
+        apr_found=1
+        break
     fi
 done
 
@@ -86,12 +107,18 @@ if [ $apr_found -lt 1 ]; then
     echo "Please refer to the documentation on APR in the httpd INSTALL file."
     echo ""
     should_exit=1
+elif [ -n "${apr_config}" ]; then
+    apr_major_version=`echo "${apr_major_version}" | sed 's/\..*//'`
 else
     apr_major_version=`grep "#define APR_MAJOR_VERSION" \
                       $apr_src_dir/include/apr_version.h | sed 's/[^0-9]//g'`
 fi
 
-if [ $apr_major_version -lt 2 ] ; then
+# Find APR-util. Note: if we're using apr-config, we can completely skip this,
+# even if APR is version 1. That's because we only end up caring about
+# find_apu.m4, which is not actually installed in the standard APR-util
+# distribution to begin with.
+if [ -z "${apr_config}" -a $apr_major_version -lt 2 ] ; then
     if test -z "$apu_src_dir"; then
         apu_src_dir=`echo $apr_src_dir | sed -e 's#/apr#/apr-util#g;'`
         apu_src_dir="$apu_src_dir `echo $apr_src_dir | sed -e 's#/apr#/aprutil#;g'`"
@@ -171,23 +198,43 @@ if [ $apr_major_version -lt 2 ] ; then
 fi
 
 echo copying build files
-cp $apr_src_dir/build/config.guess $apr_src_dir/build/config.sub \
-   $apr_src_dir/build/PrintPath $apr_src_dir/build/apr_common.m4 \
-   $apr_src_dir/build/find_apr.m4 build
-if [ $apr_major_version -lt 2 ] ; then
-    cp $apu_src_dir/build/find_apu.m4 build
+if [ -n "${apr_config}" ]; then
+    # If we're using apr-config, we switch things up a little bit:
+    # - use automake's config.* scripts instead of APR's
+    # - use the included PrintPath instead of copying from APR
+    # - assume find_apu.m4 is also in APR's --installbuilddir
+
+    # Figure out where to copy config.* from.
+    automake=${AUTOMAKE:-automake}
+    am_libdir=`"${automake}" --print-libdir`
+    cp "${am_libdir}/config.guess" "${am_libdir}/config.sub" build
+
+    # Remember that in this case, $apr_src_dir points to the build directory.
+    cp "$apr_src_dir/apr_common.m4" "$apr_src_dir/find_apr.m4" build
+    if [ $apr_major_version -lt 2 ] ; then
+        cp "$apr_src_dir/find_apu.m4" build
+    fi
+else
+    cp $apr_src_dir/build/config.guess $apr_src_dir/build/config.sub \
+       $apr_src_dir/build/PrintPath $apr_src_dir/build/apr_common.m4 \
+       $apr_src_dir/build/find_apr.m4 build
+    if [ $apr_major_version -lt 2 ] ; then
+        cp $apu_src_dir/build/find_apu.m4 build
+    fi
 fi
 
 # Remove any libtool files so one can switch between libtool 1.3
 # and libtool 1.4 by simply rerunning the buildconf script.
 (cd build ; rm -f ltconfig ltmain.sh)
 
-# Optionally copy libtool-1.3.x files
-if [ -f $apr_src_dir/build/ltconfig ]; then
-    cp $apr_src_dir/build/ltconfig build
-fi
-if [ -f $apr_src_dir/build/ltmain.sh ]; then
-    cp $apr_src_dir/build/ltmain.sh build
+if [ -z "${apr_config}" ]; then
+    # Optionally copy libtool-1.3.x files
+    if [ -f $apr_src_dir/build/ltconfig ]; then
+        cp $apr_src_dir/build/ltconfig build
+    fi
+    if [ -f $apr_src_dir/build/ltmain.sh ]; then
+        cp $apr_src_dir/build/ltmain.sh build
+    fi
 fi
 
 echo rebuilding $config_h_in