[waffle] [PATCH 6/7] nacl: add implementation for waffle_window_swap_buffers

[Tapani Pälli]

Implementation for nacl is somewhat different as for other platforms,
platform needs to ensure that the previous swap has finished before
issuing another one. This is done by introducing a worker thread that
does buffer swaps from a work queue.

Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
---
 src/waffle/nacl/nacl_container.cpp | 20 +++++++++++
 src/waffle/nacl/nacl_container.h   |  1 +
 src/waffle/nacl/nacl_swap_thread.h | 72 ++++++++++++++++++++++++++++++++++++++
 src/waffle/nacl/nacl_window.c      |  3 +-
 4 files changed, 95 insertions(+), 1 deletion(-)
 create mode 100644 src/waffle/nacl/nacl_swap_thread.h

diff --git a/src/waffle/nacl/nacl_container.cpp b/src/waffle/nacl/nacl_container.cpp
index abd64fd..4ea3f2a 100644
--- a/src/waffle/nacl/nacl_container.cpp
+++ b/src/waffle/nacl/nacl_container.cpp
@@ -28,11 +28,13 @@
 #include "ppapi/cpp/module.h"
 #include "ppapi/c/pp_errors.h"
 #include "nacl_container.h"
+#include "nacl_swap_thread.h"
 
 namespace waffle {
 
 struct nacl_container {
     pp::Graphics3D ctx;
+    NaclSwapThread *swapper;
 
     bool (*glInitializePPAPI) (PPB_GetInterface);
     void (*glSetCurrentContextPPAPI) (PP_Resource);
@@ -48,6 +50,7 @@ nacl_container_dtor(waffle::nacl_container *nc)
     nc->glSetCurrentContextPPAPI(0);
     nc->glTerminatePPAPI();
 
+    delete nc->swapper;
     delete nc;
 }
 
@@ -123,6 +126,7 @@ nacl_context_init(waffle::nacl_container *nc, struct nacl_config *cfg)
         return false;
     }
 
+    nc->swapper = new NaclSwapThread(pp_instance, nc->ctx);
     return true;
 }
 
@@ -145,6 +149,15 @@ nacl_makecurrent(waffle::nacl_container *nc)
     return true;
 }
 
+static bool
+nacl_swapbuffers(waffle::nacl_container *nc)
+{
+    if (!nc)
+        return false;
+
+    return nc->swapper->swap();
+}
+
 }; // namespace waffle ends
 
 extern "C" struct nacl_container*
@@ -180,3 +193,10 @@ nacl_makecurrent(nacl_container *nc)
     return waffle::nacl_makecurrent(
                    reinterpret_cast<waffle::nacl_container*>(nc));
 }
+
+extern "C" bool
+nacl_swapbuffers(nacl_container *nc)
+{
+    return waffle::nacl_swapbuffers(
+                   reinterpret_cast<waffle::nacl_container*>(nc));
+}
diff --git a/src/waffle/nacl/nacl_container.h b/src/waffle/nacl/nacl_container.h
index 5341141..35e848a 100644
--- a/src/waffle/nacl/nacl_container.h
+++ b/src/waffle/nacl/nacl_container.h
@@ -42,6 +42,7 @@ void nacl_teardown(struct nacl_container *nc);
 bool nacl_context_init(struct nacl_container *nc, struct nacl_config *cfg);
 bool nacl_resize(struct nacl_container *nc, int32_t width, int32_t height);
 bool nacl_makecurrent(struct nacl_container *nc);
+bool nacl_swapbuffers(struct nacl_container *nc);
 
 #ifdef __cplusplus
 };
diff --git a/src/waffle/nacl/nacl_swap_thread.h b/src/waffle/nacl/nacl_swap_thread.h
new file mode 100644
index 0000000..e735c8e
--- /dev/null
+++ b/src/waffle/nacl/nacl_swap_thread.h
@@ -0,0 +1,72 @@
+// Copyright 2014 Intel Corporation
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// - Redistributions of source code must retain the above copyright notice, this
+//   list of conditions and the following disclaimer.
+//
+// - Redistributions in binary form must reproduce the above copyright notice,
+//   this list of conditions and the following disclaimer in the documentation
+//   and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "ppapi/cpp/graphics_3d.h"
+#include "ppapi/cpp/instance.h"
+
+#include "ppapi/utility/completion_callback_factory.h"
+#include "ppapi/utility/threading/simple_thread.h"
+
+
+// Thread takes care that we do not issue another buffer
+// swap before previous swap has completed.
+class NaclSwapThread : public pp::SimpleThread
+{
+public:
+    explicit NaclSwapThread(const pp::InstanceHandle& instance,
+                            const pp::Graphics3D &_ctx) :
+        pp::SimpleThread(instance),
+        ctx(_ctx),
+        cbf(this)
+    {
+        Start();
+    }
+
+    ~NaclSwapThread()
+    {
+        message_loop().PostQuit(true);
+    }
+
+    bool swap()
+    {
+        pp::CompletionCallback cb =
+            cbf.NewCallback(&NaclSwapThread::swap_buffers);
+
+        if (message_loop().PostWork(cb) != PP_OK)
+            return false;
+
+        return true;
+    }
+
+private:
+
+    void swap_buffers(int32_t result)
+    {
+        ctx.SwapBuffers(pp::BlockUntilComplete());
+    }
+
+    pp::Graphics3D ctx;
+    pp::CompletionCallbackFactory<NaclSwapThread> cbf;
+};
diff --git a/src/waffle/nacl/nacl_window.c b/src/waffle/nacl/nacl_window.c
index eef1d1d..009e940 100644
--- a/src/waffle/nacl/nacl_window.c
+++ b/src/waffle/nacl/nacl_window.c
@@ -91,5 +91,6 @@ nacl_window_resize(struct wcore_window *wc_self,
 bool
 nacl_window_swap_buffers(struct wcore_window *wc_self)
 {
-    return false;
+    struct nacl_platform *plat = nacl_platform(wc_self->display->platform);
+    return nacl_swapbuffers(plat->nacl);
 }
-- 
2.1.0