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AX_PREFIX_CONFIG_H [(OUTPUT-HEADER [,PREFIX [,ORIG-HEADER]])]
1.3 (2003/06/04) 0.5.55 : Miscellaneous
Guiodo Draheim <guidod@gmx.de>
This is a new variant from ac_prefix_config_ this one will use a lowercase-prefix if the config-define was starting with a lowercase-char, e.g. "#define const", "#define restrict", or "#define off_t", (and this one can live in another directory, e.g. testpkg/config.h therefore I decided to move the output-header to be the first arg)
takes the usual config.h generated header file; looks for each of the generated "#define SOMEDEF" lines, and prefixes the defined name (ie. makes it "#define PREFIX_SOMEDEF". The result is written to the output config.header file. The PREFIX is converted to uppercase for the conversions.
Defaults:
OUTPUT-HEADER = $PACKAGE-config.h
PREFIX = $PACKAGE
ORIG-HEADER, from AM_CONFIG_HEADER(config.h)
Your configure.ac script should contain both macros in this order, and unlike the earlier variations of this prefix-macro it is okay to place the AX_PREFIX_CONFIG_H call before the AC_OUTPUT invokation.
Example:
AC_INIT(config.h.in) # config.h.in as created by "autoheader"
AM_INIT_AUTOMAKE(testpkg, 0.1.1) # makes #undef VERSION and PACKAGE
AM_CONFIG_HEADER(config.h) # prep config.h from config.h.in
AX_PREFIX_CONFIG_H(mylib/_config.h) # prep mylib/_config.h from it..
AC_MEMORY_H # makes "#undef NEED_MEMORY_H"
AC_C_CONST_H # makes "#undef const"
AC_OUTPUT(Makefile) # creates the "config.h" now
# and also mylib/_config.h
if the argument to AX_PREFIX_CONFIG_H would have been omitted then the default outputfile would have been called simply "testpkg-config.h", but even under the name "mylib/_config.h" it contains prefix-defines like
#ifndef TESTPKG_VERSION
#define TESTPKG_VERSION "0.1.1"
#endif
#ifndef TESTPKG_NEED_MEMORY_H
#define TESTPKG_NEED_MEMORY_H 1
#endif
#ifndef _testpkg_const
#define _testpkg_const _const
#endif
and this "mylib/_config.h" can be installed along with other header-files, which is most convenient when creating a shared library (that has some headers) where some functionality is dependent on the OS-features detected at compile-time. No need to invent some "mylib-confdefs.h.in" manually. :-)
Note that some AC_DEFINEs that end up in the config.h file are actually self-referential - e.g. AC_C_INLINE, AC_C_CONST, and the AC_TYPE_OFF_T say that they "will define inline|const|off_t if the system does not do it by itself". You might want to clean up about these - consider an extra mylib/conf.h that reads something like:
#include <mylib/_config.h>
#ifndef _testpkg_const
#define _testpkg_const const
#endif
and then start using _testpkg_const in the header files. That is also a good thing to differentiate whether some library-user has starting to take up with a different compiler, so perhaps it could read something like this:
#ifdef _MSC_VER
#include <mylib/_msvc.h>
#else
#include <mylib/_config.h>
#endif
#ifndef _testpkg_const
#define _testpkg_const const
#endif
AC_DEFUN([AX_PREFIX_CONFIG_H],[AC_REQUIRE([AC_CONFIG_HEADER]) AC_CONFIG_COMMANDS([ifelse($1,,$PACKAGE-config.h,$1)],[dnl AS_VAR_PUSHDEF([_OUT],[ac_prefix_conf_OUT])dnl AS_VAR_PUSHDEF([_DEF],[ac_prefix_conf_DEF])dnl AS_VAR_PUSHDEF([_PKG],[ac_prefix_conf_PKG])dnl AS_VAR_PUSHDEF([_LOW],[ac_prefix_conf_LOW])dnl AS_VAR_PUSHDEF([_UPP],[ac_prefix_conf_UPP])dnl AS_VAR_PUSHDEF([_INP],[ac_prefix_conf_INP])dnl m4_pushdef([_script],[conftest.prefix])dnl m4_pushdef([_symbol],[m4_cr_Letters[]m4_cr_digits[]_])dnl _OUT=`echo ifelse($1, , $PACKAGE-config.h, $1)` _DEF=`echo _$_OUT | sed -e "y:m4_cr_letters:m4_cr_LETTERS[]:" -e "s/@<:@^m4_cr_Letters@:>@/_/g"` _PKG=`echo ifelse($2, , $PACKAGE, $2)` _LOW=`echo _$_PKG | sed -e "y:m4_cr_LETTERS-:m4_cr_letters[]_:"` _UPP=`echo $_PKG | sed -e "y:m4_cr_letters-:m4_cr_LETTERS[]_:" -e "/^@<:@m4_cr_digits@:>@/s/^/_/"` _INP=`echo ifelse($3, , _, $3)` if test "$ac_prefix_conf_INP" = "_"; then for ac_file in : $CONFIG_HEADERS; do test "_$ac_file" = _: && continue test -f "$ac_prefix_conf_INP" && continue case $ac_file in *.h) test -f $ac_file && _INP=$ac_file ;; *) esac done fi if test "$_INP" = "_"; then case "$_OUT" in */*) _INP=`basename "$_OUT"` ;; *-*) _INP=`echo "$_OUT" | sed -e "s/@<:@_symbol@:>@*-//"` ;; *) _INP=config.h ;; esac fi if test -z "$_PKG" ; then AC_MSG_ERROR([no prefix for _PREFIX_PKG_CONFIG_H]) else if test ! -f "$_INP" ; then if test -f "$srcdir/$_INP" ; then _INP="$srcdir/$_INP" fi fi AC_MSG_NOTICE(creating $_OUT - prefix $_UPP for $_INP defines) if test -f $_INP ; then echo "s/@%:@undef *\\(@<:@m4_cr_LETTERS[]_@:>@\\)/@%:@undef $_UPP""_\\1/" > _script echo "s/@%:@undef *\\(@<:@m4_cr_letters@:>@\\)/@%:@undef $_LOW""_\\1/" >> _script echo "s/@%:@def[]ine *\\(@<:@m4_cr_LETTERS[]_@:>@@<:@_symbol@:>@*\\)\\(.*\\)/@%:@ifndef $_UPP""_\\1 \\" >> _script echo "@%:@def[]ine $_UPP""_\\1 \\2 \\" >> _script echo "@%:@endif/" >>_script echo "s/@%:@def[]ine *\\(@<:@m4_cr_letters@:>@@<:@_symbol@:>@*\\)\\(.*\\)/@%:@ifndef $_LOW""_\\1 \\" >> _script echo "@%:@define $_LOW""_\\1 \\2 \\" >> _script echo "@%:@endif/" >> _script # now executing _script on _DEF input to create _OUT output file echo "@%:@ifndef $_DEF" >$tmp/pconfig.h echo "@%:@def[]ine $_DEF 1" >>$tmp/pconfig.h echo ' ' >>$tmp/pconfig.h echo /'*' $_OUT. Generated automatically at end of configure. '*'/ >>$tmp/pconfig.h sed -f _script $_INP >>$tmp/pconfig.h echo ' ' >>$tmp/pconfig.h echo '/* once:' $_DEF '*/' >>$tmp/pconfig.h echo "@%:@endif" >>$tmp/pconfig.h if cmp -s $_OUT $tmp/pconfig.h 2>/dev/null; then AC_MSG_NOTICE([$_OUT is unchanged]) else ac_dir=`AS_DIRNAME(["$_OUT"])` AS_MKDIR_P(["$ac_dir"]) rm -f "$_OUT" mv $tmp/pconfig.h "$_OUT" fi cp _script _configs.sed else AC_MSG_ERROR([input file $_INP does not exist - skip generating $_OUT]) fi rm -f conftest.* fi m4_popdef([_symbol])dnl m4_popdef([_script])dnl AS_VAR_POPDEF([_INP])dnl AS_VAR_POPDEF([_UPP])dnl AS_VAR_POPDEF([_LOW])dnl AS_VAR_POPDEF([_PKG])dnl AS_VAR_POPDEF([_DEF])dnl AS_VAR_POPDEF([_OUT])dnl ],[PACKAGE="$PACKAGE"])])