101 lines
4.1 KiB
Plaintext
101 lines
4.1 KiB
Plaintext
# absolute-header.m4 serial 17
|
|
dnl Copyright (C) 2006-2022 Free Software Foundation, Inc.
|
|
dnl This file is free software; the Free Software Foundation
|
|
dnl gives unlimited permission to copy and/or distribute it,
|
|
dnl with or without modifications, as long as this notice is preserved.
|
|
|
|
dnl From Derek Price.
|
|
|
|
# gl_ABSOLUTE_HEADER(HEADER1 HEADER2 ...)
|
|
# ---------------------------------------
|
|
# Find the absolute name of a header file, testing first if the header exists.
|
|
# If the header were sys/inttypes.h, this macro would define
|
|
# ABSOLUTE_SYS_INTTYPES_H to the '""' quoted absolute name of sys/inttypes.h
|
|
# in config.h
|
|
# (e.g. '#define ABSOLUTE_SYS_INTTYPES_H "///usr/include/sys/inttypes.h"').
|
|
# The three "///" are to pacify Sun C 5.8, which otherwise would say
|
|
# "warning: #include of /usr/include/... may be non-portable".
|
|
# Use '""', not '<>', so that the /// cannot be confused with a C99 comment.
|
|
# Note: This macro assumes that the header file is not empty after
|
|
# preprocessing, i.e. it does not only define preprocessor macros but also
|
|
# provides some type/enum definitions or function/variable declarations.
|
|
AC_DEFUN([gl_ABSOLUTE_HEADER],
|
|
[AC_REQUIRE([AC_CANONICAL_HOST])
|
|
AC_LANG_PREPROC_REQUIRE()dnl
|
|
m4_foreach_w([gl_HEADER_NAME], [$1],
|
|
[AS_VAR_PUSHDEF([gl_absolute_header],
|
|
[gl_cv_absolute_]m4_defn([gl_HEADER_NAME]))dnl
|
|
AC_CACHE_CHECK([absolute name of <]m4_defn([gl_HEADER_NAME])[>],
|
|
[gl_absolute_header],
|
|
[AS_VAR_PUSHDEF([ac_header_exists],
|
|
[ac_cv_header_]m4_defn([gl_HEADER_NAME]))dnl
|
|
AC_CHECK_HEADERS_ONCE(m4_defn([gl_HEADER_NAME]))dnl
|
|
if test AS_VAR_GET([ac_header_exists]) = yes; then
|
|
gl_ABSOLUTE_HEADER_ONE(m4_defn([gl_HEADER_NAME]))
|
|
fi
|
|
AS_VAR_POPDEF([ac_header_exists])dnl
|
|
])dnl
|
|
AC_DEFINE_UNQUOTED(AS_TR_CPP([ABSOLUTE_]m4_defn([gl_HEADER_NAME])),
|
|
["AS_VAR_GET([gl_absolute_header])"],
|
|
[Define this to an absolute name of <]m4_defn([gl_HEADER_NAME])[>.])
|
|
AS_VAR_POPDEF([gl_absolute_header])dnl
|
|
])dnl
|
|
])# gl_ABSOLUTE_HEADER
|
|
|
|
# gl_ABSOLUTE_HEADER_ONE(HEADER)
|
|
# ------------------------------
|
|
# Like gl_ABSOLUTE_HEADER, except that:
|
|
# - it assumes that the header exists,
|
|
# - it uses the current CPPFLAGS,
|
|
# - it does not cache the result,
|
|
# - it is silent.
|
|
AC_DEFUN([gl_ABSOLUTE_HEADER_ONE],
|
|
[
|
|
AC_REQUIRE([AC_CANONICAL_HOST])
|
|
AC_LANG_CONFTEST([AC_LANG_SOURCE([[#include <]]m4_dquote([$1])[[>]])])
|
|
dnl AIX "xlc -E" and "cc -E" omit #line directives for header files
|
|
dnl that contain only a #include of other header files and no
|
|
dnl non-comment tokens of their own. This leads to a failure to
|
|
dnl detect the absolute name of <dirent.h>, <signal.h>, <poll.h>
|
|
dnl and others. The workaround is to force preservation of comments
|
|
dnl through option -C. This ensures all necessary #line directives
|
|
dnl are present. GCC supports option -C as well.
|
|
case "$host_os" in
|
|
aix*) gl_absname_cpp="$ac_cpp -C" ;;
|
|
*) gl_absname_cpp="$ac_cpp" ;;
|
|
esac
|
|
changequote(,)
|
|
case "$host_os" in
|
|
mingw*)
|
|
dnl For the sake of native Windows compilers (excluding gcc),
|
|
dnl treat backslash as a directory separator, like /.
|
|
dnl Actually, these compilers use a double-backslash as
|
|
dnl directory separator, inside the
|
|
dnl # line "filename"
|
|
dnl directives.
|
|
gl_dirsep_regex='[/\\]'
|
|
;;
|
|
*)
|
|
gl_dirsep_regex='\/'
|
|
;;
|
|
esac
|
|
dnl A sed expression that turns a string into a basic regular
|
|
dnl expression, for use within "/.../".
|
|
gl_make_literal_regex_sed='s,[]$^\\.*/[],\\&,g'
|
|
gl_header_literal_regex=`echo '$1' \
|
|
| sed -e "$gl_make_literal_regex_sed"`
|
|
gl_absolute_header_sed="/${gl_dirsep_regex}${gl_header_literal_regex}/"'{
|
|
s/.*"\(.*'"${gl_dirsep_regex}${gl_header_literal_regex}"'\)".*/\1/
|
|
s|^/[^/]|//&|
|
|
p
|
|
q
|
|
}'
|
|
changequote([,])
|
|
dnl eval is necessary to expand gl_absname_cpp.
|
|
dnl Ultrix and Pyramid sh refuse to redirect output of eval,
|
|
dnl so use subshell.
|
|
AS_VAR_SET([gl_cv_absolute_]AS_TR_SH([[$1]]),
|
|
[`(eval "$gl_absname_cpp conftest.$ac_ext") 2>&AS_MESSAGE_LOG_FD |
|
|
sed -n "$gl_absolute_header_sed"`])
|
|
])
|