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-rw-r--r--gnulib-m4/sys_select_h.m4110
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diff --git a/gnulib-m4/sys_select_h.m4 b/gnulib-m4/sys_select_h.m4
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+# sys_select_h.m4 serial 23
+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.
+
+AC_DEFUN_ONCE([gl_SYS_SELECT_H],
+[
+ 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],
+ [
+ dnl Test against two bugs:
+ dnl 1. On many platforms, <sys/select.h> assumes prior inclusion of
+ dnl <sys/types.h>.
+ dnl 2. On OSF/1 4.0, <sys/select.h> provides only a forward declaration
+ dnl of 'struct timeval', and no definition of this type.
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/select.h>]],
+ [[struct timeval b;]])],
+ [gl_cv_header_sys_select_h_selfcontained=yes],
+ [gl_cv_header_sys_select_h_selfcontained=no])
+ dnl Test against another bug:
+ dnl 3. On Solaris 10, <sys/select.h> provides an FD_ZERO implementation
+ dnl that relies on memset(), but without including <string.h>.
+ if test $gl_cv_header_sys_select_h_selfcontained = yes; then
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM([[#include <sys/select.h>]],
+ [[int memset; int bzero;]])
+ ],
+ [AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM([[#include <sys/select.h>]], [[
+ #undef memset
+ #define memset nonexistent_memset
+ extern
+ #ifdef __cplusplus
+ "C"
+ #endif
+ void *memset (void *, int, unsigned long);
+ #undef bzero
+ #define bzero nonexistent_bzero
+ extern
+ #ifdef __cplusplus
+ "C"
+ #endif
+ void bzero (void *, unsigned long);
+ fd_set fds;
+ FD_ZERO (&fds);
+ ]])
+ ],
+ [],
+ [gl_cv_header_sys_select_h_selfcontained=no])
+ ])
+ fi
+ ])
+ dnl <sys/select.h> is always overridden, because of GNULIB_POSIXCHECK.
+ gl_CHECK_NEXT_HEADERS([sys/select.h])
+ if test $ac_cv_header_sys_select_h = yes; then
+ HAVE_SYS_SELECT_H=1
+ else
+ HAVE_SYS_SELECT_H=0
+ fi
+ AC_SUBST([HAVE_SYS_SELECT_H])
+ gl_PREREQ_SYS_H_WINSOCK2
+
+ dnl Check for declarations of anything we want to poison if the
+ dnl corresponding gnulib module is not in use.
+ gl_WARN_ON_USE_PREPARE([[
+/* Some systems require prerequisite headers. */
+#include <sys/types.h>
+#if !(defined __GLIBC__ && !defined __UCLIBC__) && HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+#include <sys/select.h>
+ ]], [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 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],
+[
+ dnl Assume proper GNU behavior unless another module says otherwise.
+ HAVE_PSELECT=1; AC_SUBST([HAVE_PSELECT])
+ REPLACE_PSELECT=0; AC_SUBST([REPLACE_PSELECT])
+ REPLACE_SELECT=0; AC_SUBST([REPLACE_SELECT])
+])