Mojo: Implement passing of shared buffers across processes on POSIX.

mojo/system/raw_shared_buffer_win.cc

 // Copyright 2014 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 "mojo/system/raw_shared_buffer.h"
 
 #include <windows.h>
 
 #include <limits>
 
 #include "base/logging.h"
 #include "base/sys_info.h"
 #include "mojo/embedder/platform_handle.h"
 #include "mojo/embedder/scoped_platform_handle.h"
 
 namespace mojo {
 namespace system {
 
 // RawSharedBuffer -------------------------------------------------------------
 
-bool RawSharedBuffer::InitNoLock() {
+bool RawSharedBuffer::Init() {
   DCHECK(!handle_.is_valid());
 
   // TODO(vtl): Currently, we only support mapping up to 2^32-1 bytes.
   if (static_cast<uint64_t>(num_bytes_) >
           static_cast<uint64_t>(std::numeric_limits<DWORD>::max())) {
     return false;
   }
 
   // IMPORTANT NOTE: Unnamed objects are NOT SECURABLE. Thus if we ever want to
   // share read-only to other processes, we'll have to name our file mapping
   // object.
   // TODO(vtl): Unlike |base::SharedMemory|, we don't round up the size (to a
   // multiple of 64 KB). This may cause problems with NaCl. Cross this bridge
   // when we get there. crbug.com/210609
   handle_.reset(embedder::PlatformHandle(CreateFileMapping(
       INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0,
       static_cast<DWORD>(num_bytes_), NULL)));
   if (!handle_.is_valid()) {
     PLOG(ERROR) << "CreateFileMapping";
     return false;
   }
 
   return true;
 }
 
-scoped_ptr<RawSharedBufferMapping> RawSharedBuffer::MapImplNoLock(
-    size_t offset,
-    size_t length) {
-  lock_.AssertAcquired();
+bool RawSharedBuffer::InitFromPlatformHandle(
+    embedder::ScopedPlatformHandle platform_handle) {
+  DCHECK(!handle_.is_valid());
 
+  // TODO(vtl): Implement.
+  NOTIMPLEMENTED();
+  return false;
+}
+
+scoped_ptr<RawSharedBufferMapping> RawSharedBuffer::MapImpl(size_t offset,
+                                                            size_t length) {
   size_t offset_rounding = offset % base::SysInfo::VMAllocationGranularity();
   size_t real_offset = offset - offset_rounding;
   size_t real_length = length + offset_rounding;
 
   // This should hold (since we checked |num_bytes| versus the maximum value of
   // |off_t| on creation, but it never hurts to be paranoid.
   DCHECK_LE(static_cast<uint64_t>(real_offset),
             static_cast<uint64_t>(std::numeric_limits<DWORD>::max()));
 
   void* real_base = MapViewOfFile(
@@ skipping 11 matching lines @@
 
 // RawSharedBufferMapping ------------------------------------------------------
 
 void RawSharedBufferMapping::Unmap() {
   BOOL result = UnmapViewOfFile(real_base_);
   PLOG_IF(ERROR, !result) << "UnmapViewOfFile";
 }
 
 }  // namespace system
 }  // namespace mojo