Reland #2 "ipc: Add a new field num_brokered_attachments to the message header."

ipc/ipc_message.cc

 // Copyright (c) 2012 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 "ipc/ipc_message.h"
 
 #include <limits.h>
 
 #include "base/atomic_sequence_num.h"
 #include "base/logging.h"
@@ skipping 31 matching lines @@
 namespace IPC {
 
 //------------------------------------------------------------------------------
 
 Message::~Message() {
 }
 
 Message::Message() : base::Pickle(sizeof(Header)) {
   header()->routing = header()->type = 0;
   header()->flags = GetRefNumUpper24();
+#if USE_ATTACHMENT_BROKER
+  header()->num_brokered_attachments = 0;
+#endif
 #if defined(OS_POSIX)
   header()->num_fds = 0;
   header()->pad = 0;
 #endif
   Init();
 }
 
 Message::Message(int32_t routing_id, uint32_t type, PriorityValue priority)
     : base::Pickle(sizeof(Header)) {
   header()->routing = routing_id;
   header()->type = type;
   DCHECK((priority & 0xffffff00) == 0);
   header()->flags = priority | GetRefNumUpper24();
+#if USE_ATTACHMENT_BROKER
+  header()->num_brokered_attachments = 0;
+#endif
 #if defined(OS_POSIX)
   header()->num_fds = 0;
   header()->pad = 0;
 #endif
   Init();
 }
 
 Message::Message(const char* data, int data_len)
     : base::Pickle(data, data_len) {
   Init();
@@ skipping 67 matching lines @@
   const char* pickle_end =
       base::Pickle::FindNext(sizeof(Header), range_start, range_end);
   if (!pickle_end)
     return;
   info->pickle_end = pickle_end;
 
 #if USE_ATTACHMENT_BROKER
   // The data is not copied.
   size_t pickle_len = static_cast<size_t>(pickle_end - range_start);
   Message message(range_start, static_cast<int>(pickle_len));
-  int num_attachments = message.header()->num_brokered_attachments;
+  size_t num_attachments = message.header()->num_brokered_attachments;
 
   // Check for possible overflows.
   size_t max_size_t = std::numeric_limits<size_t>::max();
   if (num_attachments >= max_size_t / BrokerableAttachment::kNonceSize)
     return;
 
   size_t attachment_length = num_attachments * BrokerableAttachment::kNonceSize;
   if (pickle_len > max_size_t - attachment_length)
     return;
 
   // Check whether the range includes the attachments.
   size_t buffer_length = static_cast<size_t>(range_end - range_start);
   if (buffer_length < attachment_length + pickle_len)
     return;
 
-  for (int i = 0; i < num_attachments; ++i) {
+  for (size_t i = 0; i < num_attachments; ++i) {
     const char* attachment_start =
         pickle_end + i * BrokerableAttachment::kNonceSize;
     BrokerableAttachment::AttachmentId id(attachment_start,
                                           BrokerableAttachment::kNonceSize);
     info->attachment_ids.push_back(id);
   }
   info->message_end =
       pickle_end + num_attachments * BrokerableAttachment::kNonceSize;
 #else
   info->message_end = pickle_end;
 #endif  // USE_ATTACHMENT_BROKER
 
   info->message_found = true;
 }
 
 bool Message::AddPlaceholderBrokerableAttachmentWithId(
     BrokerableAttachment::AttachmentId id) {
   scoped_refptr<PlaceholderBrokerableAttachment> attachment(
       new PlaceholderBrokerableAttachment(id));
   return attachment_set()->AddAttachment(attachment);
 }
 
 bool Message::WriteAttachment(scoped_refptr<MessageAttachment> attachment) {
   // We write the index of the descriptor so that we don't have to
   // keep the current descriptor as extra decoding state when deserialising.
   WriteInt(attachment_set()->size());
+
+#if USE_ATTACHMENT_BROKER
+  if (attachment->GetType() == MessageAttachment::TYPE_BROKERABLE_ATTACHMENT)
+    header()->num_brokered_attachments += 1;
+#endif
+
   return attachment_set()->AddAttachment(attachment);
 }
 
 bool Message::ReadAttachment(
     base::PickleIterator* iter,
     scoped_refptr<MessageAttachment>* attachment) const {
   int descriptor_index;
   if (!iter->ReadInt(&descriptor_index))
     return false;
 
@@ skipping 12 matching lines @@
 bool Message::HasMojoHandles() const {
   return attachment_set_.get() && attachment_set_->num_mojo_handles() > 0;
 }
 
 bool Message::HasBrokerableAttachments() const {
   return attachment_set_.get() &&
          attachment_set_->num_brokerable_attachments() > 0;
 }
 
 }  // namespace IPC