Allow Mach shm to be passed to NaCl.

components/nacl/loader/nacl_ipc_adapter.cc

Index: components/nacl/loader/nacl_ipc_adapter.cc
diff --git a/components/nacl/loader/nacl_ipc_adapter.cc b/components/nacl/loader/nacl_ipc_adapter.cc
index 2f3eefcae5d8c721f5bb3f351f7da5e43313c544..b60f638ce1a481c30672f1ffa57e9f4737c8d155 100644
--- a/components/nacl/loader/nacl_ipc_adapter.cc
+++ b/components/nacl/loader/nacl_ipc_adapter.cc
@@ -227,6 +227,26 @@ class NaClDescWrapper {
   DISALLOW_COPY_AND_ASSIGN(NaClDescWrapper);
 };
 
+scoped_ptr<NaClDescWrapper> MakeShmNaClDesc(
+    const base::SharedMemoryHandle& handle,
+    size_t size) {
+#if defined(OS_MACOSX)
+  if (handle.GetType() == base::SharedMemoryHandle::MACH) {
+    return scoped_ptr<NaClDescWrapper>(new NaClDescWrapper(
+        NaClDescImcShmMachMake(handle.GetMemoryObject(), size)));
+  }
+  CHECK_EQ(base::SharedMemoryHandle::POSIX, handle.GetType());
+#endif
+
+  return scoped_ptr<NaClDescWrapper>(new NaClDescWrapper(NaClDescImcShmMake(
+#if defined(OS_WIN)
+      handle.GetHandle(),
+#else
+      base::SharedMemory::GetFdFromSharedMemoryHandle(handle),
+#endif
+      size)));
+}
+
 }  // namespace
 
 class NaClIPCAdapter::RewrittenMessage
@@ -541,15 +561,8 @@ bool NaClIPCAdapter::RewriteMessage(const IPC::Message& msg, uint32_t type) {
       scoped_ptr<NaClDescWrapper> nacl_desc;
       switch (iter->type()) {
         case ppapi::proxy::SerializedHandle::SHARED_MEMORY: {
-          const base::SharedMemoryHandle& shm_handle = iter->shmem();
-          uint32_t size = iter->size();
-          nacl_desc.reset(new NaClDescWrapper(NaClDescImcShmMake(
-#if defined(OS_WIN)
-              shm_handle.GetHandle(),
-#else
-              base::SharedMemory::GetFdFromSharedMemoryHandle(shm_handle),
-#endif
-              static_cast<size_t>(size))));
+          nacl_desc =

[Mark Seaborn, 2015/11/20 21:57:19]

Nit: the other cases do nacl_desc.reset() (though presumably it's equivalent)

[erikchen, 2015/11/20 22:00:46]

nacl_desc.reset() is being used on a raw pointer. We can use reset() here a
well, but we'd need to call .Pass() or .release() on MakeShmNaClDesc() to
convert the return value back to a raw pointer. Seems like additional effort for
no benefit?

[Mark Seaborn, 2015/11/20 22:42:36]

OK, please leave it as it is, then.  I hadn't realised the difference.

+              MakeShmNaClDesc(iter->shmem(), static_cast<size_t>(iter->size()));
           break;
         }
         case ppapi::proxy::SerializedHandle::SOCKET: {