libs.m4

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# Checking for libraries.
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# 02110-1301, USA.

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#
# Written by David MacKenzie, with help from
# Franc,ois Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor,
# Roland McGrath, Noah Friedman, david d zuhn, and many others.

# Table of contents
#
# 1. Generic tests for libraries
# 2. Tests for specific libraries


## --------------------------------- ##
## 1. Generic tests for libraries.## ##
## --------------------------------- ##



# AC_SEARCH_LIBS(FUNCTION, SEARCH-LIBS,
#                [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
#                [OTHER-LIBRARIES])
# --------------------------------------------------------
# Search for a library defining FUNC, if it's not already available.
AC_DEFUN([AC_SEARCH_LIBS],
[AS_VAR_PUSHDEF([ac_Search], [ac_cv_search_$1])dnl
AC_CACHE_CHECK([for library containing $1], ac_Search,
[ac_func_search_save_LIBS=$LIBS
AC_LANG_CONFTEST([AC_LANG_CALL([], [$1])])
for ac_lib in '' $2; do
  if test -z "$ac_lib"; then
    ac_res="none required"
  else
    ac_res=-l$ac_lib
    LIBS="-l$ac_lib $5 $ac_func_search_save_LIBS"
  fi
  AC_LINK_IFELSE([], [AS_VAR_SET(ac_Search, [$ac_res])])
  AS_VAR_SET_IF(ac_Search, [break])dnl
done
AS_VAR_SET_IF(ac_Search, , [AS_VAR_SET(ac_Search, [no])])dnl
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS])
ac_res=AS_VAR_GET(ac_Search)
AS_IF([test "$ac_res" != no],
  [test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
  $3],
      [$4])dnl
AS_VAR_POPDEF([ac_Search])dnl
])



# AC_CHECK_LIB(LIBRARY, FUNCTION,
#              [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
#              [OTHER-LIBRARIES])
# ------------------------------------------------------
#
# Use a cache variable name containing both the library and function name,
# because the test really is for library $1 defining function $2, not
# just for library $1.  Separate tests with the same $1 and different $2s
# may have different results.
#
# Note that using directly AS_VAR_PUSHDEF([ac_Lib], [ac_cv_lib_$1_$2])
# is asking for troubles, since AC_CHECK_LIB($lib, fun) would give
# ac_cv_lib_$lib_fun, which is definitely not what was meant.  Hence
# the AS_LITERAL_IF indirection.
#
# FIXME: This macro is extremely suspicious.  It DEFINEs unconditionally,
# whatever the FUNCTION, in addition to not being a *S macro.  Note
# that the cache does depend upon the function we are looking for.
#
# It is on purpose we used `ac_check_lib_save_LIBS' and not just
# `ac_save_LIBS': there are many macros which don't want to see `LIBS'
# changed but still want to use AC_CHECK_LIB, so they save `LIBS'.
# And ``ac_save_LIBS' is too tempting a name, so let's leave them some
# freedom.
AC_DEFUN([AC_CHECK_LIB],
[m4_ifval([$3], , [AH_CHECK_LIB([$1])])dnl
AS_LITERAL_IF([$1],
	      [AS_VAR_PUSHDEF([ac_Lib], [ac_cv_lib_$1_$2])],
	      [AS_VAR_PUSHDEF([ac_Lib], [ac_cv_lib_$1''_$2])])dnl
AC_CACHE_CHECK([for $2 in -l$1], ac_Lib,
[ac_check_lib_save_LIBS=$LIBS
LIBS="-l$1 $5 $LIBS"
AC_LINK_IFELSE([AC_LANG_CALL([], [$2])],
	       [AS_VAR_SET(ac_Lib, yes)],
	       [AS_VAR_SET(ac_Lib, no)])
LIBS=$ac_check_lib_save_LIBS])
AS_IF([test AS_VAR_GET(ac_Lib) = yes],
      [m4_default([$3], [AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_LIB$1))
  LIBS="-l$1 $LIBS"
])],
      [$4])dnl
AS_VAR_POPDEF([ac_Lib])dnl
])# AC_CHECK_LIB


# AH_CHECK_LIB(LIBNAME)
# ---------------------
m4_define([AH_CHECK_LIB],
[AH_TEMPLATE(AS_TR_CPP(HAVE_LIB$1),
	     [Define to 1 if you have the `]$1[' library (-l]$1[).])])


# AC_HAVE_LIBRARY(LIBRARY,
#                 [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
#                 [OTHER-LIBRARIES])
# ---------------------------------------------------------
#
# This macro is equivalent to calling `AC_CHECK_LIB' with a FUNCTION
# argument of `main'.  In addition, LIBRARY can be written as any of
# `foo', `-lfoo', or `libfoo.a'.  In all of those cases, the compiler
# is passed `-lfoo'.  However, LIBRARY cannot be a shell variable;
# it must be a literal name.
AU_DEFUN([AC_HAVE_LIBRARY],
[m4_pushdef([AC_Lib_Name],
	    m4_bpatsubst(m4_bpatsubst([[$1]],
				    [lib\([^\.]*\)\.a], [\1]),
			[-l], []))dnl
AC_CHECK_LIB(AC_Lib_Name, main, [$2], [$3], [$4])dnl
ac_cv_lib_[]AC_Lib_Name()=ac_cv_lib_[]AC_Lib_Name()_main
m4_popdef([AC_Lib_Name])dnl
])




## --------------------------------- ##
## 2. Tests for specific libraries.  ##
## --------------------------------- ##



# --------------------- #
# Checks for X window.  #
# --------------------- #


# _AC_PATH_X_XMKMF
# ----------------
# Internal subroutine of _AC_PATH_X.
# Set ac_x_includes and/or ac_x_libraries.
m4_define([_AC_PATH_X_XMKMF],
[AC_ARG_VAR(XMKMF, [Path to xmkmf, Makefile generator for X Window System])dnl
rm -f -r conftest.dir
if mkdir conftest.dir; then
  cd conftest.dir
  cat >Imakefile <<'_ACEOF'
incroot:
	@echo incroot='${INCROOT}'
usrlibdir:
	@echo usrlibdir='${USRLIBDIR}'
libdir:
	@echo libdir='${LIBDIR}'
_ACEOF
  if (export CC; ${XMKMF-xmkmf}) >/dev/null 2>/dev/null && test -f Makefile; then
    # GNU make sometimes prints "make[1]: Entering...", which would confuse us.
    for ac_var in incroot usrlibdir libdir; do
      eval "ac_im_$ac_var=\`\${MAKE-make} $ac_var 2>/dev/null | sed -n 's/^$ac_var=//p'\`"
    done
    # Open Windows xmkmf reportedly sets LIBDIR instead of USRLIBDIR.
    for ac_extension in a so sl; do
      if test ! -f "$ac_im_usrlibdir/libX11.$ac_extension" &&
	 test -f "$ac_im_libdir/libX11.$ac_extension"; then
	ac_im_usrlibdir=$ac_im_libdir; break
      fi
    done
    # Screen out bogus values from the imake configuration.  They are
    # bogus both because they are the default anyway, and because
    # using them would break gcc on systems where it needs fixed includes.
    case $ac_im_incroot in
	/usr/include) ac_x_includes= ;;
	*) test -f "$ac_im_incroot/X11/Xos.h" && ac_x_includes=$ac_im_incroot;;
    esac
    case $ac_im_usrlibdir in
	/usr/lib | /lib) ;;
	*) test -d "$ac_im_usrlibdir" && ac_x_libraries=$ac_im_usrlibdir ;;
    esac
  fi
  cd ..
  rm -f -r conftest.dir
fi
])# _AC_PATH_X_XMKMF


# _AC_PATH_X_DIRECT
# -----------------
# Internal subroutine of _AC_PATH_X.
# Set ac_x_includes and/or ac_x_libraries.
m4_define([_AC_PATH_X_DIRECT],
[# Standard set of common directories for X headers.
# Check X11 before X11Rn because it is often a symlink to the current release.
ac_x_header_dirs='
/usr/X11/include
/usr/X11R6/include
/usr/X11R5/include
/usr/X11R4/include

/usr/include/X11
/usr/include/X11R6
/usr/include/X11R5
/usr/include/X11R4

/usr/local/X11/include
/usr/local/X11R6/include
/usr/local/X11R5/include
/usr/local/X11R4/include