Enable OcclusionQueriesTest on Linux

This includes an implementation of a cross platform Sleep function

BUG=angleproject:892

Change-Id: I1087a00ab204b37bafc5e95a9766962b194d97ef
Reviewed-on: https://chromium-review.googlesource.com/273133
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>

src/tests/angle_end2end_tests.gypi

@@ -35,6 +35,7 @@
             '<(angle_path)/src/tests/gl_tests/media/pixel.inl',
             '<(angle_path)/src/tests/gl_tests/PBOExtensionTest.cpp',
             '<(angle_path)/src/tests/gl_tests/PointSpritesTest.cpp',
+            '<(angle_path)/src/tests/gl_tests/OcclusionQueriesTest.cpp',
             '<(angle_path)/src/tests/gl_tests/ProgramBinaryTest.cpp',
             '<(angle_path)/src/tests/gl_tests/ReadPixelsTest.cpp',
             '<(angle_path)/src/tests/gl_tests/RendererTest.cpp',
@@ -59,8 +60,6 @@
         ],
         'angle_end2end_tests_win_sources':
         [
-            # TODO(cwallez) for Linux, requires a portable implementation of sleep
-            '<(angle_path)/src/tests/gl_tests/OcclusionQueriesTest.cpp',
             # TODO(cwallez) for Linux, requires implementation of eglBindTexImage for pbuffers
             '<(angle_path)/src/tests/gl_tests/PbufferTest.cpp',
             '<(angle_path)/src/tests/gl_tests/QueryDisplayAttribTest.cpp',

src/tests/gl_tests/OcclusionQueriesTest.cpp

@@ -4,11 +4,9 @@
 // found in the LICENSE file.
 //
 
+#include "system_utils.h"
 #include "test_utils/ANGLETest.h"
 
-// Needed for Sleep()
-#include <Windows.h>
-
 using namespace angle;
 
 class OcclusionQueriesTest : public ANGLETest
@@ -92,7 +90,7 @@ TEST_P(OcclusionQueriesTest, IsOccluded)
     GLuint ready = GL_FALSE;
     while (ready == GL_FALSE)
     {
-        Sleep(0);
+        angle::Sleep(0);
         glGetQueryObjectuivEXT(query, GL_QUERY_RESULT_AVAILABLE_EXT, &ready);
     }
 

util/posix/Posix_system_utils.cpp

@@ -0,0 +1,37 @@
+//
+// Copyright (c) 2015 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+// Posix_system_utils.cpp: Implementation of OS-specific functions for Posix systems
+
+#include "system_utils.h"
+
+#include <sched.h>
+#include <time.h>
+
+namespace angle
+{
+
+void Sleep(unsigned int milliseconds)
+{
+    // On Windows Sleep(0) yields while it isn't guaranteed by Posix's sleep
+    // so we replicate Windows' behavior with an explicit yield.
+    if (milliseconds == 0)
+    {
+        sched_yield();
+    }
+    else
+    {
+        timespec sleepTime =
+        {
+            .tv_sec = milliseconds / 1000,
+            .tv_nsec = (milliseconds % 1000) * 1000000,
+        };
+
+        nanosleep(&sleepTime, nullptr);
+    }
+}
+
+} // namespace angle

util/system_utils.h

@@ -17,6 +17,9 @@ namespace angle
 std::string GetExecutablePath();
 std::string GetExecutableDirectory();
 
+// Cross platform equivalent of the Windows Sleep function
+void Sleep(unsigned int milliseconds);
+
 } // namespace angle
 
 #endif // SAMPLE_UTIL_PATH_UTILS_H

util/util.gyp

@@ -35,6 +35,7 @@
             'linux/Linux_system_utils.cpp',
             'linux/LinuxTimer.cpp',
             'linux/LinuxTimer.h',
+            'posix/Posix_system_utils.cpp',
             'x11/X11Window.cpp',
             'x11/X11Window.h',
         ]

util/win32/Win32_system_utils.cpp

@@ -28,4 +28,9 @@ std::string GetExecutableDirectory()
     return (lastPathSepLoc != std::string::npos) ? executablePath.substr(0, lastPathSepLoc) : "";
 }
 
+void Sleep(unsigned int milliseconds)
+{
+    ::Sleep(static_cast<DWORD>(milliseconds));
+}
+
 } // namespace angle