#

# Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.

# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

#

# This code is free software; you can redistribute it and/or modify it

# under the terms of the GNU General Public License version 2 only, as

# published by the Free Software Foundation.  Oracle designates this

# particular file as subject to the "Classpath" exception as provided

# by Oracle in the LICENSE file that accompanied this code.

#

# This code is distributed in the hope that it will be useful, but WITHOUT

# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

# version 2 for more details (a copy is included in the LICENSE file that

# accompanied this code).

#

# You should have received a copy of the GNU General Public License version

# 2 along with this work; if not, write to the Free Software Foundation,

# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

#

# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

# or visit www.oracle.com if you need additional information or have any

# questions.

#

################################################################################

# Setup libelf (ELF library)

################################################################################

AC_DEFUN_ONCE([LIB_SETUP_LIBELF],

[

  AC_ARG_WITH(libelf, [AS_HELP_STRING([--with-libelf],

      [specify prefix directory for the libelf package

      (expecting the libraries under PATH/lib and the headers under PATH/include)])])

  AC_ARG_WITH(libelf-include, [AS_HELP_STRING([--with-libelf-include],

      [specify directory for the libelf include files])])

  AC_ARG_WITH(libelf-lib, [AS_HELP_STRING([--with-libelf-lib],

      [specify directory for the libelf library])])

  if test "x$ENABLE_AOT" = xfalse; then

    if (test "x${with_libelf}" != x && test "x${with_libelf}" != xno) || \

        (test "x${with_libelf_include}" != x && test "x${with_libelf_include}" != xno) || \

        (test "x${with_libelf_lib}" != x && test "x${with_libelf_lib}" != xno); then

      AC_MSG_WARN([[libelf is not used, so --with-libelf[-*] is ignored]])

    fi

    LIBELF_CFLAGS=

    LIBELF_LIBS=

  else

    LIBELF_FOUND=no

    if test "x${with_libelf}" = xno || test "x${with_libelf_include}" = xno || test "x${with_libelf_lib}" = xno; then

      ENABLE_AOT="false"

      if test "x${enable_aot}" = xyes; then

        AC_MSG_ERROR([libelf is explicitly disabled, cannot build AOT. Enable libelf or remove --enable-aot to disable AOT.])

      fi

    else

      if test "x${with_libelf}" != x; then

        ELF_LIBS="-L${with_libelf}/lib -lelf"

        ELF_CFLAGS="-I${with_libelf}/include"

        LIBELF_FOUND=yes

      fi

      if test "x${with_libelf_include}" != x; then

        ELF_CFLAGS="-I${with_libelf_include}"

        LIBELF_FOUND=yes

      fi

      if test "x${with_libelf_lib}" != x; then

        ELF_LIBS="-L${with_libelf_lib} -lelf"

        LIBELF_FOUND=yes

      fi

      # Do not try pkg-config if we have a sysroot set.

      if test "x$SYSROOT" = x; then

        if test "x$LIBELF_FOUND" = xno; then

          # Figure out ELF_CFLAGS and ELF_LIBS

          PKG_CHECK_MODULES([ELF], [libelf], [LIBELF_FOUND=yes], [LIBELF_FOUND=no])

        fi

      fi

      if test "x$LIBELF_FOUND" = xno; then

        AC_CHECK_HEADERS([libelf.h],

            [

              LIBELF_FOUND=yes

              ELF_CFLAGS=

              ELF_LIBS=-lelf

            ],

            [LIBELF_FOUND=no]

        )

      fi

      if test "x$LIBELF_FOUND" = xno; then

        ENABLE_AOT="false"

        HELP_MSG_MISSING_DEPENDENCY([elf])

        if test "x${enable_aot}" = xyes; then

          AC_MSG_ERROR([libelf not found, cannot build AOT. Remove --enable-aot to disable AOT or: $HELP_MSG])

        else

          AC_MSG_WARN([libelf not found, cannot build AOT. $HELP_MSG])

        fi

      else

        AC_MSG_CHECKING([if libelf works])

        AC_LANG_PUSH(C)

        OLD_CFLAGS="$CFLAGS"

        CFLAGS="$CFLAGS $ELF_CFLAGS"

        OLD_LIBS="$LIBS"

        LIBS="$LIBS $ELF_LIBS"

        AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <libelf.h>],

            [

              elf_version(0);

              return 0;

            ])],

            [LIBELF_WORKS=yes],

            [LIBELF_WORKS=no]

        )

        CFLAGS="$OLD_CFLAGS"

        LIBS="$OLD_LIBS"

        AC_LANG_POP(C)

        AC_MSG_RESULT([$LIBELF_WORKS])

        if test "x$LIBELF_WORKS" = xno; then

          ENABLE_AOT="false"

          HELP_MSG_MISSING_DEPENDENCY([elf])

          if test "x$enable_aot" = "xyes"; then

            AC_MSG_ERROR([Found libelf but could not link and compile with it. Remove --enable-aot to disable AOT or: $HELP_MSG])

          else

            AC_MSG_WARN([Found libelf but could not link and compile with it. $HELP_MSG])

          fi

        fi

      fi

    fi

  fi

  AC_SUBST(ELF_CFLAGS)

  AC_SUBST(ELF_LIBS)

])