Make shared memory allocation possible for all child process types.

content/common/child_thread.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/child_thread.h"
 
 #include "base/message_loop.h"
 #include "base/string_util.h"
 #include "base/command_line.h"
 #include "content/common/child_process.h"
@@ skipping 107 matching lines @@
   DCHECK(MessageLoop::current() == message_loop());
 
   return router_.ResolveRoute(routing_id);
 }
 
 webkit_glue::ResourceLoaderBridge* ChildThread::CreateBridge(
     const webkit_glue::ResourceLoaderBridge::RequestInfo& request_info) {
   return resource_dispatcher()->CreateBridge(request_info);
 }
 
+base::SharedMemory* ChildThread::AllocateSharedMemory(
+    size_t buf_size) {
+  scoped_ptr<base::SharedMemory> shared_buf;
+#if defined(OS_WIN)
+  shared_buf.reset(new base::SharedMemory);
+  if (!shared_buf->CreateAndMapAnonymous(buf_size)) {
+    NOTREACHED();
+    return NULL;
+  }
+#else
+  // On POSIX, we need to ask the browser to create the shared memory for us,
+  // since this is blocked by the sandbox.
+  base::SharedMemoryHandle shared_mem_handle;
+  if (Send(new ChildProcessHostMsg_SyncAllocateSharedMemory(
+                   buf_size, &shared_mem_handle))) {
+    if (base::SharedMemory::IsHandleValid(shared_mem_handle)) {
+      shared_buf.reset(new base::SharedMemory(shared_mem_handle, false));
+      if (!shared_buf->Map(buf_size)) {
+        NOTREACHED() << "Map failed";
+        return NULL;
+      }
+    } else {
+      NOTREACHED() << "Browser failed to allocate shared memory";
+      return NULL;
+    }
+  } else {
+    NOTREACHED() << "Browser allocation request message failed";
+    return NULL;
+  }
+#endif
+  return shared_buf.release();
+}
+
 ResourceDispatcher* ChildThread::resource_dispatcher() {
   return resource_dispatcher_.get();
 }
 
 IPC::SyncMessageFilter* ChildThread::sync_message_filter() {
   return sync_message_filter_;
 }
 
 MessageLoop* ChildThread::message_loop() {
   return message_loop_;
@@ skipping 75 matching lines @@
     MessageLoop::current()->Quit();
     return;
   }
 
   // The child process shutdown sequence is a request response based mechanism,
   // where we send out an initial feeler request to the child process host
   // instance in the browser to verify if it's ok to shutdown the child process.
   // The browser then sends back a response if it's ok to shutdown.
   Send(new ChildProcessHostMsg_ShutdownRequest);
 }