dnl   configuration script for expat
dnl   Process this file with autoconf to produce a configure script.
dnl
dnl   Copyright 2000 Clark Cooper
dnl
dnl   This file is part of EXPAT.
dnl
dnl   EXPAT is free software; you can redistribute it and/or modify it
dnl   under the terms of the License (based on the MIT/X license) contained
dnl   in the file COPYING that comes with this distribution.
dnl

dnl Ensure that Expat is configured with autoconf 2.58 or newer
AC_PREREQ(2.58)

dnl Get the version number of Expat, using m4's esyscmd() command to run
dnl the command at m4-generation time. This allows us to create an m4
dnl symbol holding the correct version number. AC_INIT() requires the
dnl version number at m4-time, rather than when ./configure is run, so
dnl all this must happen as part of m4, not as part of the shell code
dnl contained in ./configure.
dnl
dnl NOTE: esyscmd() is a GNU M4 extension. Thus, we wrap it in an appropriate
dnl test. I believe this test will work, but I don't have a place with non-
dnl GNU M4 to test it right now.
define([expat_version], ifdef([__gnu__],
                              [esyscmd(conftools/get-version.sh lib/expat.h)],
                              [2.2.x]))
AC_INIT(expat, expat_version, expat-bugs@libexpat.org)
undefine([expat_version])

AC_CONFIG_SRCDIR(Makefile.in)
AC_CONFIG_AUX_DIR(conftools)
AM_INIT_AUTOMAKE
AC_CONFIG_MACRO_DIR([m4])


dnl
dnl Increment LIBREVISION if source code has changed at all
dnl
dnl If the API has changed, increment LIBCURRENT and set LIBREVISION to 0
dnl
dnl If the API changes compatibly (i.e. simply adding a new function
dnl without changing or removing earlier interfaces), then increment LIBAGE.
dnl 
dnl If the API changes incompatibly set LIBAGE back to 0
dnl

LIBCURRENT=7   # sync
LIBREVISION=6  # with
LIBAGE=6       # CMakeLists.txt!

CPPFLAGS="${CPPFLAGS} -DHAVE_EXPAT_CONFIG_H"
AC_CONFIG_HEADER(expat_config.h)

sinclude(conftools/ac_c_bigendian_cross.m4)

AC_LIBTOOL_WIN32_DLL
AC_PROG_LIBTOOL

AC_SUBST(LIBCURRENT)
AC_SUBST(LIBREVISION)
AC_SUBST(LIBAGE)

dnl Checks for programs.
AC_PROG_CC_C99
AC_PROG_CXX
AC_PROG_INSTALL

if test "$GCC" = yes ; then
    dnl
    dnl Be careful about adding the -fexceptions option; some versions of
    dnl GCC don't support it and it causes extra warnings that are only
    dnl distracting; avoid.
    dnl
    OLDCFLAGS="$CFLAGS -Wall -Wmissing-prototypes -Wstrict-prototypes"
    CFLAGS="$OLDCFLAGS -fexceptions"
    AC_MSG_CHECKING(whether $CC accepts -fexceptions)
    AC_TRY_LINK( , ,
                   AC_MSG_RESULT(yes),
                   AC_MSG_RESULT(no); CFLAGS="$OLDCFLAGS")
    if test "x$CXXFLAGS" = x ; then
    CXXFLAGS=`echo "$CFLAGS" | sed 's/ -Wmissing-prototypes -Wstrict-prototypes//'`
    fi

    CFLAGS="${CFLAGS} -fno-strict-aliasing"
    CXXFLAGS="${CXXFLAGS} -fno-strict-aliasing"
    LDFLAGS="${LDFLAGS} -fno-strict-aliasing"
fi

dnl Checks for header files.
AC_HEADER_STDC

dnl Checks for typedefs, structures, and compiler characteristics.

dnl Note: Avoid using AC_C_BIGENDIAN because it does not
dnl work in a cross compile.
AC_C_BIGENDIAN_CROSS

AC_C_CONST
AC_TYPE_SIZE_T
AC_CHECK_FUNCS(memmove bcopy)


AC_ARG_WITH([xmlwf], [
AS_HELP_STRING([--without-xmlwf], [do not build xmlwf])], [], [with_xmlwf=yes])
AM_CONDITIONAL([WITH_XMLWF], [test x${with_xmlwf} = xyes])


AC_ARG_WITH([libbsd], [
AS_HELP_STRING([--with-libbsd], [utilize libbsd (for arc4random_buf)])
], [], [with_libbsd=no])
AS_IF([test "x${with_libbsd}" != xno], [
  AC_CHECK_LIB([bsd], [arc4random_buf], [], [
    AS_IF([test "x${with_libbsd}" = xyes], [
      AC_MSG_ERROR([Enforced use of libbsd cannot be satisfied.])
    ])
  ])
])
AC_MSG_CHECKING([for arc4random_buf (BSD or libbsd)])
AC_LINK_IFELSE([AC_LANG_SOURCE([
  #include <stdlib.h>  /* for arc4random_buf on BSD, for NULL */
  #if defined(HAVE_LIBBSD)
  # include <bsd/stdlib.h>
  #endif
  int main() {
    arc4random_buf(NULL, 0U);
    return 0;
  }
])], [
    AC_DEFINE([HAVE_ARC4RANDOM_BUF], [1],
        [Define to 1 if you have the `arc4random_buf' function.])
    AC_MSG_RESULT([yes])
], [
    AC_MSG_RESULT([no])

    AC_MSG_CHECKING([for arc4random (BSD, macOS or libbsd)])
    AC_LINK_IFELSE([AC_LANG_SOURCE([
      #if defined(HAVE_LIBBSD)
      # include <bsd/stdlib.h>
      #else
      # include <stdlib.h>
      #endif
      int main() {
          arc4random();
          return 0;
      }
    ])], [
        AC_DEFINE([HAVE_ARC4RANDOM], [1],
            [Define to 1 if you have the `arc4random' function.])
        AC_MSG_RESULT([yes])
    ], [
        AC_MSG_RESULT([no])
    ])
])


AC_MSG_CHECKING([for getrandom (Linux 3.17+, glibc 2.25+)])
AC_LINK_IFELSE([AC_LANG_SOURCE([
  #include <stdlib.h>  /* for NULL */
  #include <sys/random.h>
  int main() {
    return getrandom(NULL, 0U, 0U);
  }
])], [
    AC_DEFINE([HAVE_GETRANDOM], [1],
        [Define to 1 if you have the `getrandom' function.])
    AC_MSG_RESULT([yes])
], [
    AC_MSG_RESULT([no])

    AC_MSG_CHECKING([for syscall SYS_getrandom (Linux 3.17+)])
    AC_LINK_IFELSE([AC_LANG_SOURCE([
      #include <stdlib.h>  /* for NULL */
      #include <unistd.h>  /* for syscall */
      #include <sys/syscall.h>  /* for SYS_getrandom */
      int main() {
        syscall(SYS_getrandom, NULL, 0, 0);
        return 0;
      }
    ])], [
        AC_DEFINE([HAVE_SYSCALL_GETRANDOM], [1],
            [Define to 1 if you have `syscall' and `SYS_getrandom'.])
        AC_MSG_RESULT([yes])
    ], [
        AC_MSG_RESULT([no])
    ])
])


dnl Only needed for xmlwf:
AC_CHECK_HEADERS(fcntl.h unistd.h)
AC_TYPE_OFF_T
AC_FUNC_MMAP

if test "$ac_cv_func_mmap_fixed_mapped" = "yes"; then
    FILEMAP=unixfilemap
else
    FILEMAP=readfilemap
fi
AC_SUBST(FILEMAP)


dnl Some basic configuration:
AC_DEFINE([XML_NS], 1,
          [Define to make XML Namespaces functionality available.])
AC_DEFINE([XML_DTD], 1,
          [Define to make parameter entity parsing functionality available.])
AC_DEFINE([XML_DEV_URANDOM], 1,
          [Define to include code reading entropy from `/dev/urandom'.])

AC_ARG_ENABLE([xml-context],
  AS_HELP_STRING([--enable-xml-context @<:@COUNT@:>@],
    [Retain context around the current parse point;
        default is enabled and a size of 1024 bytes])
AS_HELP_STRING([--disable-xml-context],
    [Do not retain context around the current parse point]),
  [enable_xml_context=${enableval}])
AS_IF([test "x${enable_xml_context}" != "xno"], [
  AS_IF([test "x${enable_xml_context}" = "xyes" \
      -o "x${enable_xml_context}" = "x"], [
    enable_xml_context=1024
  ])
  AC_DEFINE_UNQUOTED([XML_CONTEXT_BYTES], [${enable_xml_context}],
    [Define to specify how much context to retain around the current parse point.])
])

AC_CONFIG_FILES([Makefile expat.pc])
AC_CONFIG_FILES([
  doc/Makefile
  examples/Makefile
  lib/Makefile
  tests/Makefile
  tests/benchmark/Makefile
  xmlwf/Makefile
])
AC_CONFIG_FILES([run.sh], [chmod +x run.sh])
AC_OUTPUT
