Merge commit 'a39d4083cab589d7cd6a13e8a4b8db8875261d75'

[gnulib.git] / m4 / sched_h.m4

diff --git a/m4/sched_h.m4 b/m4/sched_h.m4
index 697d829..329af35 100644 (file)
--- a/m4/sched_h.m4
+++ b/m4/sched_h.m4
@@ -1,5 +1,5 @@
-# sched_h.m4 serial 1
-dnl Copyright (C) 2008 Free Software Foundation, Inc.
+# sched_h.m4 serial 6
+dnl Copyright (C) 2008-2014 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.
@@ -8,11 +8,33 @@ dnl Written by Bruno Haible.
 
 AC_DEFUN([gl_SCHED_H],
 [
-  AC_CHECK_HEADERS_ONCE([sched.h])
-  if test $ac_cv_header_sched_h = yes; then
-    SCHED_H=''
-  else
-    SCHED_H='sched.h'
-  fi
+  AC_COMPILE_IFELSE(
+    [AC_LANG_PROGRAM([[
+       #include <sched.h>
+       struct sched_param a;
+       int b[] = { SCHED_FIFO, SCHED_RR, SCHED_OTHER };
+       pid_t t1;
+     ]])],
+    [SCHED_H=''],
+    [SCHED_H='sched.h'
+
+     gl_CHECK_NEXT_HEADERS([sched.h])
+
+     if test $ac_cv_header_sched_h = yes; then
+       HAVE_SCHED_H=1
+     else
+       HAVE_SCHED_H=0
+     fi
+     AC_SUBST([HAVE_SCHED_H])
+
+     AC_CHECK_TYPE([struct sched_param],
+       [HAVE_STRUCT_SCHED_PARAM=1], [HAVE_STRUCT_SCHED_PARAM=0],
+       [#include <sched.h>])
+     AC_SUBST([HAVE_STRUCT_SCHED_PARAM])
+
+     dnl Ensure the type pid_t gets defined.
+     AC_REQUIRE([AC_TYPE_PID_T])
+    ])
   AC_SUBST([SCHED_H])
+  AM_CONDITIONAL([GL_GENERATE_SCHED_H], [test -n "$SCHED_H"])
 ])