| # absolute-header.m4 serial 16 |
| dnl Copyright (C) 2006-2016 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 |
| dnl FIXME: gl_absolute_header and ac_header_exists must be used unquoted |
| dnl until we can assume autoconf 2.64 or newer. |
| 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])[>], |
| m4_defn([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"`]) |
| ]) |