diff options
Diffstat (limited to 'm4/sys_select_h.m4')
| -rw-r--r-- | m4/sys_select_h.m4 | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/m4/sys_select_h.m4 b/m4/sys_select_h.m4 index 4b33d312e55..2e7d140dee2 100644 --- a/m4/sys_select_h.m4 +++ b/m4/sys_select_h.m4 @@ -1,13 +1,13 @@ -# sys_select_h.m4 serial 20 +# sys_select_h.m4 serial 23 dnl Copyright (C) 2006-2021 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. -AC_DEFUN([gl_HEADER_SYS_SELECT], +AC_DEFUN_ONCE([gl_SYS_SELECT_H], [ - AC_REQUIRE([AC_C_RESTRICT]) AC_REQUIRE([gl_SYS_SELECT_H_DEFAULTS]) + AC_REQUIRE([AC_C_RESTRICT]) AC_CACHE_CHECK([whether <sys/select.h> is self-contained], [gl_cv_header_sys_select_h_selfcontained], [ @@ -75,19 +75,34 @@ AC_DEFUN([gl_HEADER_SYS_SELECT], ]], [pselect select]) ]) +# gl_SYS_SELECT_MODULE_INDICATOR([modulename]) +# sets the shell variable that indicates the presence of the given module +# to a C preprocessor expression that will evaluate to 1. +# This macro invocation must not occur in macros that are AC_REQUIREd. AC_DEFUN([gl_SYS_SELECT_MODULE_INDICATOR], [ - dnl Use AC_REQUIRE here, so that the default settings are expanded once only. - AC_REQUIRE([gl_SYS_SELECT_H_DEFAULTS]) + dnl Ensure to expand the default settings once only. + gl_SYS_SELECT_H_REQUIRE_DEFAULTS gl_MODULE_INDICATOR_SET_VARIABLE([$1]) dnl Define it also as a C macro, for the benefit of the unit tests. gl_MODULE_INDICATOR_FOR_TESTS([$1]) ]) +# Initializes the default values for AC_SUBSTed shell variables. +# This macro must not be AC_REQUIREd. It must only be invoked, and only +# outside of macros or in macros that are not AC_REQUIREd. +AC_DEFUN([gl_SYS_SELECT_H_REQUIRE_DEFAULTS], +[ + m4_defun(GL_MODULE_INDICATOR_PREFIX[_SYS_SELECT_H_MODULE_INDICATOR_DEFAULTS], [ + gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_PSELECT]) + gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_SELECT]) + ]) + m4_require(GL_MODULE_INDICATOR_PREFIX[_SYS_SELECT_H_MODULE_INDICATOR_DEFAULTS]) + AC_REQUIRE([gl_SYS_SELECT_H_DEFAULTS]) +]) + AC_DEFUN([gl_SYS_SELECT_H_DEFAULTS], [ - GNULIB_PSELECT=0; AC_SUBST([GNULIB_PSELECT]) - GNULIB_SELECT=0; AC_SUBST([GNULIB_SELECT]) dnl Assume proper GNU behavior unless another module says otherwise. HAVE_PSELECT=1; AC_SUBST([HAVE_PSELECT]) REPLACE_PSELECT=0; AC_SUBST([REPLACE_PSELECT]) |