aclocal.m4

fdisk 实现源码,可以查询Linux下系统的分区信息

[
  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
  AC_REQUIRE([AC_LIB_RPATH])
  define([Name],[translit([$1],[./-], [___])])
  define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
                               [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
  AC_CACHE_CHECK([how to link with lib[]$1], [ac_cv_lib[]Name[]_libs], [
    AC_LIB_LINKFLAGS_BODY([$1], [$2])
    ac_cv_lib[]Name[]_libs="$LIB[]NAME"
    ac_cv_lib[]Name[]_ltlibs="$LTLIB[]NAME"
    ac_cv_lib[]Name[]_cppflags="$INC[]NAME"
  ])
  LIB[]NAME="$ac_cv_lib[]Name[]_libs"
  LTLIB[]NAME="$ac_cv_lib[]Name[]_ltlibs"
  INC[]NAME="$ac_cv_lib[]Name[]_cppflags"
  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
  AC_SUBST([LIB]NAME)
  AC_SUBST([LTLIB]NAME)
  dnl Also set HAVE_LIB[]NAME so that AC_LIB_HAVE_LINKFLAGS can reuse the
  dnl results of this search when this library appears as a dependency.
  HAVE_LIB[]NAME=yes
  undefine([Name])
  undefine([NAME])
])

dnl AC_LIB_HAVE_LINKFLAGS(name, dependencies, includes, testcode)
dnl searches for libname and the libraries corresponding to explicit and
dnl implicit dependencies, together with the specified include files and
dnl the ability to compile and link the specified testcode. If found, it
dnl sets and AC_SUBSTs HAVE_LIB${NAME}=yes and the LIB${NAME} and
dnl LTLIB${NAME} variables and augments the CPPFLAGS variable, and
dnl #defines HAVE_LIB${NAME} to 1. Otherwise, it sets and AC_SUBSTs
dnl HAVE_LIB${NAME}=no and LIB${NAME} and LTLIB${NAME} to empty.
AC_DEFUN([AC_LIB_HAVE_LINKFLAGS],
[
  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
  AC_REQUIRE([AC_LIB_RPATH])
  define([Name],[translit([$1],[./-], [___])])
  define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
                               [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])

  dnl Search for lib[]Name and define LIB[]NAME, LTLIB[]NAME and INC[]NAME
  dnl accordingly.
  AC_LIB_LINKFLAGS_BODY([$1], [$2])

  dnl Add $INC[]NAME to CPPFLAGS before performing the following checks,
  dnl because if the user has installed lib[]Name and not disabled its use
  dnl via --without-lib[]Name-prefix, he wants to use it.
  ac_save_CPPFLAGS="$CPPFLAGS"
  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)

  AC_CACHE_CHECK([for lib[]$1], [ac_cv_lib[]Name], [
    ac_save_LIBS="$LIBS"
    LIBS="$LIBS $LIB[]NAME"
    AC_TRY_LINK([$3], [$4], [ac_cv_lib[]Name=yes], [ac_cv_lib[]Name=no])
    LIBS="$ac_save_LIBS"
  ])
  if test "$ac_cv_lib[]Name" = yes; then
    HAVE_LIB[]NAME=yes
    AC_DEFINE([HAVE_LIB]NAME, 1, [Define if you have the $1 library.])
    AC_MSG_CHECKING([how to link with lib[]$1])
    AC_MSG_RESULT([$LIB[]NAME])
  else
    HAVE_LIB[]NAME=no
    dnl If $LIB[]NAME didn't lead to a usable library, we don't need
    dnl $INC[]NAME either.
    CPPFLAGS="$ac_save_CPPFLAGS"
    LIB[]NAME=
    LTLIB[]NAME=
  fi
  AC_SUBST([HAVE_LIB]NAME)
  AC_SUBST([LIB]NAME)
  AC_SUBST([LTLIB]NAME)
  undefine([Name])
  undefine([NAME])
])

dnl Determine the platform dependent parameters needed to use rpath:
dnl libext, shlibext, hardcode_libdir_flag_spec, hardcode_libdir_separator,
dnl hardcode_direct, hardcode_minus_L.
AC_DEFUN([AC_LIB_RPATH],
[
  dnl Tell automake >= 1.10 to complain if config.rpath is missing.
  m4_ifdef([AC_REQUIRE_AUX_FILE], [AC_REQUIRE_AUX_FILE([config.rpath])])
  AC_REQUIRE([AC_PROG_CC])                dnl we use $CC, $GCC, $LDFLAGS
  AC_REQUIRE([AC_LIB_PROG_LD])            dnl we use $LD, $with_gnu_ld
  AC_REQUIRE([AC_CANONICAL_HOST])         dnl we use $host
  AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT]) dnl we use $ac_aux_dir
  AC_CACHE_CHECK([for shared library run path origin], acl_cv_rpath, [
    CC="$CC" GCC="$GCC" LDFLAGS="$LDFLAGS" LD="$LD" with_gnu_ld="$with_gnu_ld" \
    ${CONFIG_SHELL-/bin/sh} "$ac_aux_dir/config.rpath" "$host" > conftest.sh
    . ./conftest.sh
    rm -f ./conftest.sh
    acl_cv_rpath=done
  ])
  wl="$acl_cv_wl"
  libext="$acl_cv_libext"
  shlibext="$acl_cv_shlibext"
  hardcode_libdir_flag_spec="$acl_cv_hardcode_libdir_flag_spec"
  hardcode_libdir_separator="$acl_cv_hardcode_libdir_separator"
  hardcode_direct="$acl_cv_hardcode_direct"
  hardcode_minus_L="$acl_cv_hardcode_minus_L"
  dnl Determine whether the user wants rpath handling at all.
  AC_ARG_ENABLE(rpath,
    [  --disable-rpath         do not hardcode runtime library paths],
    :, enable_rpath=yes)
])

dnl AC_LIB_LINKFLAGS_BODY(name [, dependencies]) searches for libname and
dnl the libraries corresponding to explicit and implicit dependencies.
dnl Sets the LIB${NAME}, LTLIB${NAME} and INC${NAME} variables.
AC_DEFUN([AC_LIB_LINKFLAGS_BODY],
[
  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
  define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
                               [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
  dnl By default, look in $includedir and $libdir.
  use_additional=yes
  AC_LIB_WITH_FINAL_PREFIX([
    eval additional_includedir=\"$includedir\"
    eval additional_libdir=\"$libdir\"
  ])
  AC_LIB_ARG_WITH([lib$1-prefix],
[  --with-lib$1-prefix[=DIR]  search for lib$1 in DIR/include and DIR/lib
  --without-lib$1-prefix     don't search for lib$1 in includedir and libdir],
[
    if test "X$withval" = "Xno"; then
      use_additional=no
    else
      if test "X$withval" = "X"; then
        AC_LIB_WITH_FINAL_PREFIX([
          eval additional_includedir=\"$includedir\"
          eval additional_libdir=\"$libdir\"
        ])
      else
        additional_includedir="$withval/include"
        additional_libdir="$withval/$acl_libdirstem"
      fi
    fi
])
  dnl Search the library and its dependencies in $additional_libdir and
  dnl $LDFLAGS. Using breadth-first-seach.
  LIB[]NAME=
  LTLIB[]NAME=
  INC[]NAME=
  rpathdirs=
  ltrpathdirs=
  names_already_handled=
  names_next_round='$1 $2'
  while test -n "$names_next_round"; do
    names_this_round="$names_next_round"
    names_next_round=
    for name in $names_this_round; do
      already_handled=
      for n in $names_already_handled; do
        if test "$n" = "$name"; then
          already_handled=yes
          break
        fi
      done
      if test -z "$already_handled"; then
        names_already_handled="$names_already_handled $name"
        dnl See if it was already located by an earlier AC_LIB_LINKFLAGS
        dnl or AC_LIB_HAVE_LINKFLAGS call.
        uppername=`echo "$name" | sed -e 'y|abcdefghijklmnopqrstuvwxyz./-|ABCDEFGHIJKLMNOPQRSTUVWXYZ___|'`
        eval value=\"\$HAVE_LIB$uppername\"
        if test -n "$value"; then
          if test "$value" = yes; then
            eval value=\"\$LIB$uppername\"
            test -z "$value" || LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$value"
            eval value=\"\$LTLIB$uppername\"
            test -z "$value" || LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$value"
          else
            dnl An earlier call to AC_LIB_HAVE_LINKFLAGS has determined
            dnl that this library doesn't exist. So just drop it.
            :
          fi
        else
          dnl Search the library lib$name in $additional_libdir and $LDFLAGS
          dnl and the already constructed $LIBNAME/$LTLIBNAME.
          found_dir=
          found_la=
          found_so=
          found_a=
          if test $use_additional = yes; then
            if test -n "$shlibext" \
               && { test -f "$additional_libdir/lib$name.$shlibext" \
                    || { test "$shlibext" = dll \
                         && test -f "$additional_libdir/lib$name.dll.a"; }; }; then
              found_dir="$additional_libdir"
              if test -f "$additional_libdir/lib$name.$shlibext"; then
                found_so="$additional_libdir/lib$name.$shlibext"
              else
                found_so="$additional_libdir/lib$name.dll.a"
              fi
              if test -f "$additional_libdir/lib$name.la"; then
                found_la="$additional_libdir/lib$name.la"
              fi
            else
              if test -f "$additional_libdir/lib$name.$libext"; then
                found_dir="$additional_libdir"
                found_a="$additional_libdir/lib$name.$libext"
                if test -f "$additional_libdir/lib$name.la"; then
                  found_la="$additional_libdir/lib$name.la"
                fi
              fi
            fi
          fi
          if test "X$found_dir" = "X"; then
            for x in $LDFLAGS $LTLIB[]NAME; do
              AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
              case "$x" in
                -L*)
                  dir=`echo "X$x" | sed -e 's/^X-L//'`
                  if test -n "$shlibext" \
                     && { test -f "$dir/lib$name.$shlibext" \
                          || { test "$shlibext" = dll \
                               && test -f "$dir/lib$name.dll.a"; }; }; then
                    found_dir="$dir"
                    if test -f "$dir/lib$name.$shlibext"; then
                      found_so="$dir/lib$name.$shlibext"
                    else
                      found_so="$dir/lib$name.dll.a"
                    fi
                    if test -f "$dir/lib$name.la"; then
                      found_la="$dir/lib$name.la"
                    fi
                  else
                    if test -f "$dir/lib$name.$libext"; then
                      found_dir="$dir"
                      found_a="$dir/lib$name.$libext"
                      if test -f "$dir/lib$name.la"; then
                        found_la="$dir/lib$name.la"
                      fi
                    fi
                  fi
                  ;;
              esac
              if test "X$found_dir" != "X"; then
                break
              fi
            done
          fi
          if test "X$found_dir" != "X"; then
            dnl Found the library.
            LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$found_dir -l$name"
            if test "X$found_so" != "X"; then
              dnl Linking with a shared library. We attempt to hardcode its
              dnl directory into the executable's runpath, unless it's the
              dnl standard /usr/lib.
              if test "$enable_rpath" = no || test "X$found_dir" = "X/usr/$acl_libdirstem"; then
                dnl No hardcoding is needed.
                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
              else
                dnl Use an explicit option to hardcode DIR into the resulting
                dnl binary.
                dnl Potentially add DIR to ltrpathdirs.
                dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
                haveit=
                for x in $ltrpathdirs; do
                  if test "X$x" = "X$found_dir"; then
                    haveit=yes
                    break
                  fi
                done
                if test -z "$haveit"; then
                  ltrpathdirs="$ltrpathdirs $found_dir"
                fi
                dnl The hardcoding into $LIBNAME is system dependent.
                if test "$hardcode_direct" = yes; then
                  dnl Using DIR/libNAME.so during linking hardcodes DIR into the
                  dnl resulting binary.
                  LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
                else
                  if test -n "$hardcode_libdir_flag_spec" && test "$hardcode_minus_L" = no; then
                    dnl Use an explicit option to hardcode DIR into the resulting
                    dnl binary.
                    LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
                    dnl Potentially add DIR to rpathdirs.
                    dnl The rpathdirs will be appended to $LIBNAME at the end.
                    haveit=
                    for x in $rpathdirs; do
                      if test "X$x" = "X$found_dir"; then
                        haveit=yes
                        break
                      fi
                    done
                    if test -z "$haveit"; then
                      rpathdirs="$rpathdirs $found_dir"
                    fi
                  else
                    dnl Rely on "-L$found_dir".
                    dnl But don't add it if it's already contained in the LDFLAGS
                    dnl or the already constructed $LIBNAME
                    haveit=
                    for x in $LDFLAGS $LIB[]NAME; do
                      AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
                      if test "X$x" = "X-L$found_dir"; then
                        haveit=yes
                        break
                      fi
                    done
                    if test -z "$haveit"; then
                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir"
                    fi
                    if test "$hardcode_minus_L" != no; then
                      dnl FIXME: Not sure whether we should use
                      dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
                      dnl here.
                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
                    else
                      dnl We cannot use $hardcode_runpath_var and LD_RUN_PATH
                      dnl here, because this doesn't fit in flags passed to the
                      dnl compiler. So give up. No hardcoding. This affects only
                      dnl very old systems.
                      dnl FIXME: Not sure whether we should use
                      dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
                      dnl here.
                      LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
                    fi
                  fi
                fi
              fi
            else
              if test "X$found_a" != "X"; then
                dnl Linking with a static library.
                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_a"
              else
                dnl We shouldn't come here, but anyway it's good to have a
                dnl fallback.
                LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir -l$name"
              fi
            fi