From 44631aa023c58990f13ca50050567033cfa9da3f Mon Sep 17 00:00:00 2001
From: Alexander Larsson <alexl@redhat.com>
Date: Wed, 29 Sep 2010 13:16:45 +0200
Subject: [PATCH] client: Check for pthread yield function using autoconf

---
 client/x11/platform.cpp |  2 +-
 configure.ac            | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/client/x11/platform.cpp b/client/x11/platform.cpp
index cc1502bd..a9b4449d 100644
--- a/client/x11/platform.cpp
+++ b/client/x11/platform.cpp
@@ -463,7 +463,7 @@ void Platform::msleep(unsigned int millisec)
 
 void Platform::yield()
 {
-    pthread_yield();
+    POSIX_YIELD_FUNC;
 }
 
 void Platform::term_printf(const char* format, ...)
diff --git a/configure.ac b/configure.ac
index 3369ddee..76f90711 100644
--- a/configure.ac
+++ b/configure.ac
@@ -128,6 +128,26 @@ AC_SUBST(LIBRT)
 
 SPICE_NONPKGCONFIG_LIBS+=" -pthread $LIBM $LIBRT"
 
+dnl The client needs a yield function
+AC_MSG_CHECKING(for posix yield function)
+for yield_func in pthread_yield pthread_yield_np sched_yield \
+					thr_yield; do
+    spice_save_CPPFLAGS="$CPPFLAGS"
+    CPPFLAGS="$CPPFLAGS $SPICE_NONPKGCONFIG_LIBS"
+    AC_TRY_LINK([#include <pthread.h>],
+		[$yield_func()],
+		[posix_yield_func="$yield_func"
+		break])
+    CPPFLAGS="spice_save_CPPFLAGS"
+done
+if test x"$posix_yield_func" = xnone; then
+    AC_MSG_ERROR([No posix yield function found])
+else
+    AC_MSG_RESULT($posix_yield_func)
+    posix_yield_func="$posix_yield_func()"
+fi
+AC_DEFINE_UNQUOTED(POSIX_YIELD_FUNC,$posix_yield_func,[The POSIX RT yield function])
+
 SPICE_REQUIRES=""
 
 if test "x$use_gui" = "xyes"; then