Media Galleries API Metadata: SafeMediaMetadataParser and IPCTunnelDataReader.

chrome/utility/chrome_content_utility_client.cc

Index: chrome/utility/chrome_content_utility_client.cc
diff --git a/chrome/utility/chrome_content_utility_client.cc b/chrome/utility/chrome_content_utility_client.cc
index 48acaa94ea95781f133a9d6958c52b39b8c47a53..7e20ed416e69ec6787b37f854e9067ad81fac546 100644
--- a/chrome/utility/chrome_content_utility_client.cc
+++ b/chrome/utility/chrome_content_utility_client.cc
@@ -11,7 +11,6 @@
 #include "base/files/file_path.h"
 #include "base/json/json_reader.h"
 #include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/scoped_native_library.h"
 #include "base/time/time.h"
@@ -61,6 +60,11 @@
 #include "chrome/utility/media_galleries/picasa_albums_indexer.h"
 #endif  // defined(OS_WIN) || defined(OS_MACOSX)
 
+#if !defined(OS_ANDROID) && !defined(OS_IOS)
+#include "chrome/utility/media_galleries/ipc_tunnel_data_source.h"
+#include "chrome/utility/media_galleries/media_metadata_parser.h"
+#endif  // !defined(OS_ANDROID) && !defined(OS_IOS)
+
 #if defined(ENABLE_FULL_PRINTING)
 #include "chrome/common/crash_keys.h"
 #include "printing/backend/print_backend.h"
@@ -289,6 +293,12 @@ typedef PdfFunctionsWin PdfFunctions;
 typedef PdfFunctionsBase PdfFunctions;
 #endif  // OS_WIN
 
+void SendMediaMetadataToHost(
+    scoped_ptr<extensions::api::media_galleries::MediaMetadata> metadata) {
+  Send(new ChromeUtilityHostMsg_ParseMediaMetadata_Finished(
+      true, *(metadata->ToValue().get())));
+}
+
 static base::LazyInstance<PdfFunctions> g_pdf_lib = LAZY_INSTANCE_INITIALIZER;
 
 }  // namespace
@@ -342,6 +352,11 @@ bool ChromeContentUtilityClient::OnMessageReceived(
 
 #if !defined(OS_ANDROID) && !defined(OS_IOS)
     IPC_MESSAGE_HANDLER(ChromeUtilityMsg_CheckMediaFile, OnCheckMediaFile)
+    IPC_MESSAGE_HANDLER(ChromeUtilityMsg_ParseMediaMetadata,
+                        OnParseMediaMetadata)
+    IPC_MESSAGE_HANDLER(
+        ChromeUtilityMsg_ParseMediaMetadata_RequestBlobBytes_Finished,
+        OnParseMediaMetadataRequestBlobBytesFinished)
 #endif  // !defined(OS_ANDROID) && !defined(OS_IOS)
 
 #if defined(OS_CHROMEOS)
@@ -759,6 +774,26 @@ void ChromeContentUtilityClient::OnCheckMediaFile(
   Send(new ChromeUtilityHostMsg_CheckMediaFile_Finished(check_success));
   ReleaseProcessIfNeeded();
 }
+
+void ChromeContentUtilityClient::OnParseMediaMetadata(
+    const std::string& mime_type,
+    int64 total_size) {
+  DCHECK(!media_metadata_parser_);
+  DCHECK(!ipc_tunnel_data_source_);
+
+  ipc_tunnel_data_source_.reset(new metadata::IPCTunnelDataSource(total_size));
+  media_metadata_parser_.reset(new metadata::MediaMetadataParser(
+      ipc_tunnel_data_source_.get(), mime_type));
+  media_metadata_parser_->Start(base::Bind(&SendMediaMetadataToHost));
+}
+
+void ChromeContentUtilityClient::OnParseMediaMetadataRequestBlobBytesFinished(

[vandebo (ex-Chrome), 2014/01/07 18:34:59]

I suggest making IPCDataSource a message Listener and adding it to |handlers_|. 
That way it will both send and receive message instead of only sending them. 
However, you'd need a mechanism to remove it from handlers_ as well and that may
not be worth the effort...

[tommycli, 2014/01/07 20:23:31]

Done. This is better, but I have one concern left:

What if in a different function, another IPCDataSource is created and added to
handlers_? In that case, the newly created IPCDataSource will never receive any
messages.

I think whether or not this will become a problem - and the solution, will
become apparent in further CLs though, so I'm okay with this for right now...

+    int64 request_id,
+    const std::string& bytes) {
+  if (!ipc_tunnel_data_source_)
+    return;
+  ipc_tunnel_data_source_->ReceiveBytes(request_id, bytes);
+}
 #endif  // !defined(OS_ANDROID) && !defined(OS_IOS)
 
 #if defined(OS_WIN)