dnl ===================================================================
dnl   Licensed to the Apache Software Foundation (ASF) under one
dnl   or more contributor license agreements.  See the NOTICE file
dnl   distributed with this work for additional information
dnl   regarding copyright ownership.  The ASF licenses this file
dnl   to you under the Apache License, Version 2.0 (the
dnl   "License"); you may not use this file except in compliance
dnl   with the License.  You may obtain a copy of the License at
dnl
dnl     http://www.apache.org/licenses/LICENSE-2.0
dnl
dnl   Unless required by applicable law or agreed to in writing,
dnl   software distributed under the License is distributed on an
dnl   "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
dnl   KIND, either express or implied.  See the License for the
dnl   specific language governing permissions and limitations
dnl   under the License.
dnl ===================================================================
dnl
dnl find_apr.m4 : locate the APR include files and libraries
dnl
dnl This macro file can be used by applications to find and use the APR
dnl library. It provides a standardized mechanism for using APR. It supports
dnl embedding APR into the application source, or locating an installed
dnl copy of APR.
dnl
dnl APR_FIND_APR(srcdir, builddir, implicit-install-check, acceptable-majors)
dnl
dnl   where srcdir is the location of the bundled APR source directory, or
dnl   empty if source is not bundled.
dnl
dnl   where builddir is the location where the bundled APR will will be built,
dnl   or empty if the build will occur in the srcdir.
dnl
dnl   where implicit-install-check set to 1 indicates if there is no
dnl   --with-apr option specified, we will look for installed copies.
dnl
dnl   where acceptable-majors is a space separated list of acceptable major
dnl   version numbers. Often only a single major version will be acceptable.
dnl   If multiple versions are specified, and --with-apr=PREFIX or the
dnl   implicit installed search are used, then the first (leftmost) version
dnl   in the list that is found will be used.  Currently defaults to [0 1].
dnl
dnl Sets the following variables on exit:
dnl
dnl   apr_found : "yes", "no", "reconfig"
dnl
dnl   apr_config : If the apr-config tool exists, this refers to it. If
dnl                apr_found is "reconfig", then the bundled directory
dnl                should be reconfigured *before* using apr_config.
dnl
dnl Note: this macro file assumes that apr-config has been installed; it
dnl       is normally considered a required part of an APR installation.
dnl
dnl If a bundled source directory is available and needs to be (re)configured,
dnl then apr_found is set to "reconfig". The caller should reconfigure the
dnl (passed-in) source directory, placing the result in the build directory,
dnl as appropriate.
dnl
dnl If apr_found is "yes" or "reconfig", then the caller should use the
dnl value of apr_config to fetch any necessary build/link information.
dnl

AC_DEFUN([APR_FIND_APR], [
  apr_found="no"

  if test "$ac_cv_emxos2" = "yes"; then
    # Scripts don't pass test -x on OS/2
    TEST_X="test -f"
  else
    TEST_X="test -x"
  fi

  ifelse([$4], [], [
         ifdef(AC_WARNING,AC_WARNING([$0: missing argument 4 (acceptable-majors): Defaulting to APR 0.x then APR 1.x]))
         acceptable_majors="0 1"],
         [acceptable_majors="$4"])

  apr_temp_acceptable_apr_config=""
  for apr_temp_major in $acceptable_majors
  do
    case $apr_temp_major in
      0)
      apr_temp_acceptable_apr_config="$apr_temp_acceptable_apr_config apr-config"
      ;;
      *)
      apr_temp_acceptable_apr_config="$apr_temp_acceptable_apr_config apr-$apr_temp_major-config"
      ;;
    esac
  done

  AC_MSG_CHECKING(for APR)
  AC_ARG_WITH(apr,
  [  --with-apr=PATH         prefix for installed APR, path to APR build tree,
                          or the full path to apr-config],
  [
    if test "$withval" = "no" || test "$withval" = "yes"; then
      AC_MSG_ERROR([--with-apr requires a directory or file to be provided])
    fi

    for apr_temp_apr_config_file in $apr_temp_acceptable_apr_config
    do
      for lookdir in "$withval/bin" "$withval"
      do
        if $TEST_X "$lookdir/$apr_temp_apr_config_file"; then
          apr_found="yes"
          apr_config="$lookdir/$apr_temp_apr_config_file"
          break 2
        fi
      done
    done

    if test "$apr_found" != "yes" && $TEST_X "$withval" && $withval --help > /dev/null 2>&1 ; then
      apr_found="yes"
      apr_config="$withval"
    fi

    dnl if --with-apr is used, it is a fatal error for its argument
    dnl to be invalid
    if test "$apr_found" != "yes"; then
      AC_MSG_ERROR([the --with-apr parameter is incorrect. It must specify an install prefix, a build directory, or an apr-config file.])
    fi
  ],[
    dnl if we have a bundled source directory, use it
    if test -d "$1"; then
      apr_temp_abs_srcdir="`cd $1 && pwd`"
      apr_found="reconfig"
      apr_bundled_major="`sed -n '/#define.*APR_MAJOR_VERSION/s/^[^0-9]*\([0-9]*\).*$/\1/p' \"$1/include/apr_version.h\"`"
      case $apr_bundled_major in
        "")
          AC_MSG_ERROR([failed to find major version of bundled APR])
        ;;
        0)
          apr_temp_apr_config_file="apr-config"
        ;;
        *)
          apr_temp_apr_config_file="apr-$apr_bundled_major-config"
        ;;
      esac
      if test -n "$2"; then
        apr_config="$2/$apr_temp_apr_config_file"
      else
        apr_config="$1/$apr_temp_apr_config_file"
      fi
    fi
    if test "$apr_found" = "no" && test -n "$3" && test "$3" = "1"; then
      for apr_temp_apr_config_file in $apr_temp_acceptable_apr_config
      do
        if $apr_temp_apr_config_file --help > /dev/null 2>&1 ; then
          apr_found="yes"
          apr_config="$apr_temp_apr_config_file"
          break
        else
          dnl look in some standard places (apparently not in builtin/default)
          for lookdir in /usr /usr/local /opt/apr /usr/local/apache2 ; do
            if $TEST_X "$lookdir/bin/$apr_temp_apr_config_file"; then
              apr_found="yes"
              apr_config="$lookdir/bin/$apr_temp_apr_config_file"
              break 2
            fi
          done
        fi
      done
    fi
  ])

  AC_MSG_RESULT($apr_found)
])