[BlobAsync] Patch 3: Renderer Classes & Logic

content/child/blob_storage/blob_transport_controller.cc

+// Copyright 2015 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/child/blob_storage/blob_transport_controller.h"
+
+#include <vector>
+
+#include "base/containers/scoped_ptr_hash_map.h"
+#include "base/lazy_instance.h"
+#include "base/memory/shared_memory.h"
+#include "base/stl_util.h"
+#include "content/child/blob_storage/blob_consolidation.h"
+#include "content/child/thread_safe_sender.h"
+#include "ipc/ipc_sender.h"
+#include "storage/common/blob_storage/blob_item_bytes_request.h"
+#include "storage/common/blob_storage/blob_item_bytes_response.h"
+#include "storage/common/data_element.h"
+
+using base::SharedMemory;
+using base::SharedMemoryHandle;
+using storage::BlobItemBytesRequest;
+using storage::BlobItemBytesResponse;
+using storage::IPCBlobItemRequestStrategy;
+using storage::DataElement;
+
+namespace content {
+
+using storage::IPCBlobCreationCancelCode;
+
+using ConsolidatedItem = BlobConsolidation::ConsolidatedItem;
+using ReadStatus = BlobConsolidation::ReadStatus;
+
+namespace {
+const size_t kLargeThresholdBytes = 250 * 1024;
+static base::LazyInstance<BlobTransportController> controller_ =
+    LAZY_INSTANCE_INITIALIZER;
+}
+
+BlobTransportController* BlobTransportController::GetInstance() {
+  return controller_.Pointer();
+}
+
+BlobTransportController::~BlobTransportController() {
+  STLDeleteValues(&blob_storage_);
+}
+
+void BlobTransportController::InitiateBlobTransfer(
+    const std::string& uuid,
+    const std::string& type,
+    scoped_ptr<BlobConsolidation> consolidation,
+    IPC::Sender* sender) {
+  bool not_found = HoldBlobConsolidation(uuid, consolidation.Pass());

[michaeln, 2015/10/22 21:10:22]

per the style-guide, to defend against duplicate uuid values in release builds
use CHECK

   auto insert_result = blob_storage_.insert(
       std::make_pair(uuid, consolidation.release()));
   CHECK(insert_result.second);

also, probably don't need the helper method to do that

[dmurph, 2015/10/22 23:43:04]

Ok. I'll keep HoldBlob* as we use it in the tests.

+  DCHECK(not_found);
+  if (!not_found) {
+    DVLOG(1) << "Blob " << uuid << " already being sent to browser.";
+    return;
+  }
+
+  std::vector<storage::DataElement> descriptions;
+  GetDescriptions(uuid, kLargeThresholdBytes, &descriptions);
+  // TODO(dmurph): Uncomment when IPC messages are added.
+  // sender->Send(new BlobStorageMsg_StartBuildingBlob(uuid, type,
+  // descriptions));
+}
+
+void BlobTransportController::OnMemoryRequest(
+    const std::string& uuid,
+    const std::vector<storage::BlobItemBytesRequest>& requests,
+    std::vector<base::SharedMemoryHandle>* memory_handles,
+    const std::vector<IPC::PlatformFileForTransit>& file_handles,
+    IPC::Sender* sender) {
+  std::vector<storage::BlobItemBytesResponse> responses;
+  ResponsesStatus status =
+      GetResponses(uuid, requests, memory_handles, file_handles, &responses);
+
+  bool success = false;
+  switch (status) {
+    case ResponsesStatus::BLOB_NOT_FOUND:
+      DVLOG(1) << "Unable to find blob " << uuid << ".";
+      return;
+    case ResponsesStatus::INVALID_ITEM_INDEX:
+      DVLOG(1) << "Index out of bounds for blob item in blob " << uuid << ".";
+      break;
+    case ResponsesStatus::INVALID_DATA_RANGE:
+      DVLOG(1) << "Data range out of bounds for blob item in blob " << uuid
+               << ".";
+      break;
+    case ResponsesStatus::INVALID_ITEM:
+      DVLOG(1) << "Requesting data from non-memory item in blob " << uuid
+               << ".";
+      break;
+    case ResponsesStatus::INVALID_HANDLE_INDEX:
+      DVLOG(1) << "Invalid handle index for transferring in blob " << uuid
+               << ".";
+      break;
+    case ResponsesStatus::SHARED_MEMORY_MAP_FAILED:
+      // This would happen if the renderer process doesn't have enough memory
+      // to map the shared memory, which is possible if we don't have much
+      // memory. If this scenario happens often, we could delay the response
+      // until we have enough memory.  For now we just fail.
+      DVLOG(1) << "Unable to map shared memory to send blob " << uuid << ".";
+      break;
+    case ResponsesStatus::SUCCESS:
+      success = true;
+      break;
+  }
+
+  if (success) {
+    // TODO(dmurph): Uncomment when IPC messages are added.
+    // sender->Send(new BlobStorageMsg_MemoryItemResponse(uuid, responses));
+  } else {
+    DVLOG(1) << "Canceling blob transfer for blob " << uuid;
+    CancelBlobTransfer(uuid, IPCBlobCreationCancelCode::UNKNOWN, sender);
+  }
+}
+
+void BlobTransportController::OnCancel(
+    const std::string& uuid,
+    storage::IPCBlobCreationCancelCode code) {
+  DVLOG(1) << "Received blob cancel for blob " << uuid << " with reason:";
+  switch (code) {
+    case IPCBlobCreationCancelCode::UNKNOWN:
+      DVLOG(1) << "Unknown.";
+      break;
+    case IPCBlobCreationCancelCode::OUT_OF_MEMORY:
+      DVLOG(1) << "Out of Memory.";
+      break;
+    case IPCBlobCreationCancelCode::FILE_WRITE_FAILED:
+      DVLOG(1) << "File Write Failed (Invalid cancel reason!).";
+      break;
+  }
+  ReleaseBlob(uuid);
+}
+
+void BlobTransportController::OnDone(const std::string& uuid) {
+  ReleaseBlob(uuid);
+}
+
+void BlobTransportController::Clear() {
+  STLDeleteValues(&blob_storage_);
+  blob_storage_.clear();
+}
+
+BlobTransportController::BlobTransportController() {}
+
+void BlobTransportController::CancelBlobTransfer(
+    const std::string& uuid,
+    storage::IPCBlobCreationCancelCode code,
+    IPC::Sender* sender) {
+  // TODO(dmurph): Uncomment when IPC messages are added.
+  // sender->Send(new BlobStorageMsg_CancelBuildingBlob(uuid, code));
+  ReleaseBlob(uuid);
+}
+
+bool BlobTransportController::HoldBlobConsolidation(
+    const std::string& uuid,
+    scoped_ptr<BlobConsolidation> consolidation) {
+  if (blob_storage_.find(uuid) != blob_storage_.end()) {
+    return false;
+  }
+  blob_storage_.insert(std::make_pair(uuid, consolidation.release()));
+  return true;
+}
+
+void BlobTransportController::GetDescriptions(
+    const std::string& uuid,
+    size_t max_data_population,
+    std::vector<storage::DataElement>* out) {
+  DCHECK(out->empty());
+  BlobConsolidation* consolidation = GetConsolidation(uuid);
+  if (!consolidation) {
+    return;
+  }
+  const auto& consolidated_items = consolidation->consolidated_items();
+
+  size_t current_memory_population = 0;
+  size_t current_item = 0;
+  out->reserve(consolidated_items.size());
+  for (const ConsolidatedItem& item : consolidated_items) {
+    out->push_back(DataElement());
+    auto& element = out->back();
+
+    switch (item.type) {
+      case DataElement::TYPE_BYTES: {
+        size_t bytes_length = static_cast<size_t>(item.length);
+        if (current_memory_population + bytes_length <= max_data_population) {
+          element.SetToAllocatedBytes(bytes_length);
+          consolidation->ReadMemory(current_item, 0, bytes_length,
+                                    element.mutable_bytes());
+          current_memory_population += bytes_length;
+        } else {
+          element.SetToBytesDescription(bytes_length);
+        }
+        break;
+      }
+      case DataElement::TYPE_FILE: {
+        element.SetToFilePathRange(
+            item.path, item.offset, item.length,
+            base::Time::FromDoubleT(item.expected_modification_time));
+        break;
+      }
+      case DataElement::TYPE_BLOB: {
+        element.SetToBlobRange(item.blob_uuid, item.offset, item.length);
+        break;
+      }
+      case DataElement::TYPE_FILE_FILESYSTEM: {
+        element.SetToFileSystemUrlRange(
+            item.filesystem_url, item.offset, item.length,
+            base::Time::FromDoubleT(item.expected_modification_time));
+        break;
+      }
+      case DataElement::TYPE_DISK_CACHE_ENTRY:
+      case DataElement::TYPE_BYTES_DESCRIPTION:
+      case DataElement::TYPE_UNKNOWN:
+        NOTREACHED();
+    }
+    ++current_item;
+  }
+}
+
+BlobTransportController::ResponsesStatus BlobTransportController::GetResponses(
+    const std::string& uuid,
+    const std::vector<BlobItemBytesRequest>& requests,
+    std::vector<SharedMemoryHandle>* memory_handles,
+    const std::vector<IPC::PlatformFileForTransit>& file_handles,
+    std::vector<BlobItemBytesResponse>* out) {
+  DCHECK(out->empty());
+  BlobConsolidation* consolidation = GetConsolidation(uuid);
+  if (!consolidation)
+    return ResponsesStatus::BLOB_NOT_FOUND;
+  const auto& consolidated_items = consolidation->consolidated_items();
+
+  base::ScopedPtrHashMap<size_t, scoped_ptr<SharedMemory>> opened_memory;
+  for (const BlobItemBytesRequest& request : requests) {
+    if (request.renderer_item_index >= consolidated_items.size())
+      return ResponsesStatus::INVALID_ITEM_INDEX;
+
+    const ConsolidatedItem& item =
+        consolidated_items[request.renderer_item_index];
+    if (request.renderer_item_offset + request.size > item.length)
+      return ResponsesStatus::INVALID_DATA_RANGE;
+    if (item.type != DataElement::TYPE_BYTES)
+      return ResponsesStatus::INVALID_ITEM;
+
+    out->push_back(BlobItemBytesResponse(request.request_number));
+    switch (request.transport_strategy) {
+      case IPCBlobItemRequestStrategy::IPC: {
+        BlobItemBytesResponse& response = out->back();
+        ReadStatus status = consolidation->ReadMemory(
+            request.renderer_item_index, request.renderer_item_offset,
+            request.size, response.allocate_mutable_data(request.size));
+        CHECK(status == ReadStatus::OK)
+            << "Error reading from consolidated blob: "
+            << static_cast<int>(status);
+        break;
+      }
+      case IPCBlobItemRequestStrategy::SHARED_MEMORY: {
+        if (request.handle_index >= memory_handles->size()) {
+          DCHECK_LT(request.handle_index, memory_handles->size());
+          return ResponsesStatus::INVALID_HANDLE_INDEX;
+        }
+        SharedMemory* memory = nullptr;
+        auto memory_it = opened_memory.find(request.handle_index);
+        if (memory_it == opened_memory.end()) {
+          SharedMemoryHandle& handle = (*memory_handles)[request.handle_index];
+          DCHECK(SharedMemory::IsHandleValid(handle));
+          scoped_ptr<SharedMemory> shared_memory(
+              new SharedMemory(handle, false));
+          if (!shared_memory->Map(request.size))
+            return ResponsesStatus::SHARED_MEMORY_MAP_FAILED;
+          memory = shared_memory.get();
+          opened_memory.add(request.handle_index, shared_memory.Pass());
+        } else {
+          memory = memory_it->second;
+        }
+        CHECK(memory->memory()) << "Couldn't map memory for blob transfer.";
+        ReadStatus status = consolidation->ReadMemory(
+            request.renderer_item_index, request.renderer_item_offset,
+            request.size,
+            static_cast<char*>(memory->memory()) + request.handle_offset);
+        CHECK(status == ReadStatus::OK)
+            << "Error reading from consolidated blob: "
+            << static_cast<int>(status);
+        break;
+      }
+      case IPCBlobItemRequestStrategy::FILE:
+        NOTREACHED() << "TODO(dmurph): Not implemented.";
+        break;
+      case IPCBlobItemRequestStrategy::UNKNOWN:
+        NOTREACHED();
+        break;
+    }
+  }
+  return ResponsesStatus::SUCCESS;
+}
+
+void BlobTransportController::ReleaseBlob(const std::string& uuid) {
+  auto iter = blob_storage_.find(uuid);
+  if (iter != blob_storage_.end()) {
+    BlobConsolidation* consolidation = iter->second;
+    delete consolidation;
+    blob_storage_.erase(iter);
+  }
+}
+
+BlobConsolidation* BlobTransportController::GetConsolidation(
+    const std::string& uuid) {
+  auto iter = blob_storage_.find(uuid);
+  if (iter == blob_storage_.end())
+    return nullptr;
+  return iter->second;
+}
+
+}  // namespace content