1 files changed, 66 insertions, 0 deletions
diff --git a/m4/gethrxtime.m4 b/m4/gethrxtime.m4
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+++ b/m4/gethrxtime.m4
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+# gethrxtime.m4 serial 13
+dnl Copyright (C) 2005-2006, 2008-2020 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 Written by Paul Eggert.
+
+AC_DEFUN([gl_GETHRXTIME],
+[
+  AC_REQUIRE([gl_ARITHMETIC_HRTIME_T])
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_REQUIRE([gl_XTIME])
+  AC_CHECK_DECLS([gethrtime], [], [], [[#include <time.h>]])
+  LIB_GETHRXTIME=
+  if test $ac_cv_have_decl_gethrtime = no \
+     || test $gl_cv_arithmetic_hrtime_t = no; then
+    dnl Find libraries needed to link lib/gethrxtime.c.
+    AC_REQUIRE([gl_CLOCK_TIME])
+    AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+    AC_CHECK_FUNCS_ONCE([microuptime nanouptime])
+    if test $ac_cv_func_nanouptime != yes \
+       && { test $ac_cv_have_decl_gethrtime = no \
+            || test $gl_cv_arithmetic_hrtime_t = no; }; then
+      AC_CACHE_CHECK([whether CLOCK_MONOTONIC or CLOCK_REALTIME is defined],
+        [gl_cv_have_clock_gettime_macro],
+        [AC_EGREP_CPP([have_clock_gettime_macro],
+          [
+#          include <time.h>
+#          if defined CLOCK_MONOTONIC || defined CLOCK_REALTIME
+            have_clock_gettime_macro
+#          endif
+          ],
+          [gl_cv_have_clock_gettime_macro=yes],
+          [gl_cv_have_clock_gettime_macro=no])])
+      if test $gl_cv_have_clock_gettime_macro = yes; then
+        LIB_GETHRXTIME=$LIB_CLOCK_GETTIME
+      fi
+    fi
+  fi
+  AC_SUBST([LIB_GETHRXTIME])
+])
+
+# Test whether hrtime_t is an arithmetic type.
+# It is not arithmetic in older Solaris c89 (which insists on
+# not having a long long int type).
+AC_DEFUN([gl_ARITHMETIC_HRTIME_T],
+[
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_CACHE_CHECK([for arithmetic hrtime_t], [gl_cv_arithmetic_hrtime_t],
+    [AC_COMPILE_IFELSE(
+       [AC_LANG_PROGRAM([[#include <time.h>]],
+          [[hrtime_t x = 0; return x/x;]])],
+       [gl_cv_arithmetic_hrtime_t=yes],
+       [gl_cv_arithmetic_hrtime_t=no])])
+  if test $gl_cv_arithmetic_hrtime_t = yes; then
+    AC_DEFINE([HAVE_ARITHMETIC_HRTIME_T], [1],
+      [Define if you have an arithmetic hrtime_t type.])
+  fi
+])
+
+# Prerequisites of lib/xtime.h.
+AC_DEFUN([gl_XTIME],
+[
+  :
+])