[BlobStorage] Implementing disk.

content/child/blob_storage/blob_transport_controller.cc

Index: content/child/blob_storage/blob_transport_controller.cc
diff --git a/content/child/blob_storage/blob_transport_controller.cc b/content/child/blob_storage/blob_transport_controller.cc
index 5db46a24726647bcf614777b5eb9322ae038a877..ba9aded2cfeca88efe65b2bd54bbb8eb5a362dc8 100644
--- a/content/child/blob_storage/blob_transport_controller.cc
+++ b/content/child/blob_storage/blob_transport_controller.cc
@@ -82,6 +82,7 @@ bool WriteSingleChunk(base::File* file, const char* memory, size_t size) {
     int actual_written =
         file->WriteAtCurrentPos(memory, static_cast<int>(writing_size));
     bool write_failed = actual_written < 0;
+    LOG_IF(ERROR, write_failed) << "Write failed";
     UMA_HISTOGRAM_BOOLEAN("Storage.Blob.RendererFileWriteFailed", write_failed);
     if (write_failed)
       return false;
@@ -90,27 +91,25 @@ bool WriteSingleChunk(base::File* file, const char* memory, size_t size) {
   return true;
 }
 
-base::Optional<base::Time> WriteSingleRequestToDisk(
-    const BlobConsolidation* consolidation,
-    const BlobItemBytesRequest& request,
-    File* file) {
+bool WriteSingleRequestToDisk(const BlobConsolidation* consolidation,
+                              const BlobItemBytesRequest& request,
+                              File* file) {
   if (!file->IsValid())
-    return base::nullopt;
+    return false;
   int64_t seek_distance = file->Seek(
       File::FROM_BEGIN, base::checked_cast<int64_t>(request.handle_offset));
   bool seek_failed = seek_distance < 0;
   UMA_HISTOGRAM_BOOLEAN("Storage.Blob.RendererFileSeekFailed", seek_failed);
   if (seek_failed) {
-    return base::nullopt;
+    LOG(ERROR) << "Seek failed";
+    return false;
   }
   BlobConsolidation::ReadStatus status = consolidation->VisitMemory(
       request.renderer_item_index, request.renderer_item_offset, request.size,
       base::Bind(&WriteSingleChunk, file));
   if (status != BlobConsolidation::ReadStatus::OK)
-    return base::nullopt;
-  File::Info info;
-  file->GetInfo(&info);
-  return base::make_optional(info.last_modified);
+    return false;
+  return true;
 }
 
 base::Optional<std::vector<BlobItemBytesResponse>> WriteDiskRequests(
@@ -118,8 +117,6 @@ base::Optional<std::vector<BlobItemBytesResponse>> WriteDiskRequests(
     std::unique_ptr<std::vector<BlobItemBytesRequest>> requests,
     const std::vector<IPC::PlatformFileForTransit>& file_handles) {
   std::vector<BlobItemBytesResponse> responses;
-  std::vector<base::Time> last_modified_times;
-  last_modified_times.resize(file_handles.size());
   // We grab ownership of the file handles here. When this vector is destroyed
   // it will close the files.
   std::vector<File> files;
@@ -127,14 +124,27 @@ base::Optional<std::vector<BlobItemBytesResponse>> WriteDiskRequests(
   for (const auto& file_handle : file_handles) {
     files.emplace_back(IPC::PlatformFileForTransitToFile(file_handle));
   }
+  // First we write everything, then we flush, then we grab the last modified
+  // times.
   for (const auto& request : *requests) {
-    base::Optional<base::Time> last_modified = WriteSingleRequestToDisk(
-        consolidation.get(), request, &files[request.handle_index]);
-    if (!last_modified) {
+    if (!WriteSingleRequestToDisk(consolidation.get(), request,
+                                  &files[request.handle_index])) {
       return base::nullopt;
     }
-    last_modified_times[request.handle_index] = last_modified.value();
   }
+  std::vector<base::Time> last_modified_times;
+  last_modified_times.resize(file_handles.size());
+  for (size_t i = 0; i < files.size(); ++i) {
+    auto& file = files[i];
+    if (!file.Flush())
+      return base::nullopt;
+    File::Info info;
+    if (!file.GetInfo(&info))
+      return base::nullopt;
+    LOG(ERROR) << "got post-flush modified time " << info.last_modified;
+    last_modified_times[i] = info.last_modified;
+  }
+
   for (const auto& request : *requests) {
     responses.push_back(BlobItemBytesResponse(request.request_number));
     responses.back().time_file_modified =
@@ -381,6 +391,7 @@ void BlobTransportController::OnFileWriteComplete(
   if (blob_storage_.find(uuid) == blob_storage_.end())
     return;
   if (!result) {
+    LOG(ERROR) << "Error writing files";
     sender->Send(new BlobStorageMsg_SendBlobStatus(
         uuid, BlobStatus::ERR_FILE_WRITE_FAILED));
     ReleaseBlobConsolidation(uuid);