Adds imageWriterPrivate support for Windows

chrome/browser/extensions/api/image_writer_private/operation.cc

Index: chrome/browser/extensions/api/image_writer_private/operation.cc
diff --git a/chrome/browser/extensions/api/image_writer_private/operation.cc b/chrome/browser/extensions/api/image_writer_private/operation.cc
index a37c81c4e6755c4b553f9f820b04bd53e9d103da..a6361c8fa4fcd5aceccedaf314e78d0b1bbaf0fc 100644
--- a/chrome/browser/extensions/api/image_writer_private/operation.cc
+++ b/chrome/browser/extensions/api/image_writer_private/operation.cc
@@ -36,14 +36,11 @@ Operation::Operation(base::WeakPtr<OperationManager> manager,
       progress_(0) {
 }
 
-Operation::~Operation() {
-}
+Operation::~Operation() {}
 
 void Operation::Cancel() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
-  DVLOG(1) << "Cancelling image writing operation for ext: " << extension_id_;
-
   stage_ = image_writer_api::STAGE_NONE;
 
   CleanUp();
@@ -97,16 +94,17 @@ void Operation::SetProgress(int progress) {
     return;
   }
 
-  progress_ = progress;
+  if (progress > progress_) {
+    progress_ = progress;
 
-  BrowserThread::PostTask(
-      BrowserThread::UI,
-      FROM_HERE,
-      base::Bind(&OperationManager::OnProgress,
-                 manager_,
-                 extension_id_,
-                 stage_,
-                 progress_));
+    BrowserThread::PostTask(BrowserThread::UI,
+                            FROM_HERE,
+                            base::Bind(&OperationManager::OnProgress,
+                                       manager_,
+                                       extension_id_,
+                                       stage_,
+                                       progress_));
+  }
 }
 
 void Operation::SetStage(image_writer_api::Stage stage) {
@@ -144,7 +142,6 @@ void Operation::Finish() {
                             base::Bind(&Operation::Finish, this));
     return;
   }
-  DVLOG(1) << "Write operation complete.";
 
   CleanUp();
 
@@ -178,13 +175,41 @@ void Operation::CleanUp() {
   cleanup_functions_.clear();
 }
 
-void Operation::UnzipStart(scoped_ptr<base::FilePath> zip_path) {
+void Operation::StartImageWriterClient() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+  if (!image_writer_client_) {
+    image_writer_client_ = new ImageWriterClient();
+
+    AddCleanUpFunction(base::Bind(&Operation::StopImageWriterClient, this));
+  }
+}
+
+void Operation::StopImageWriterClient() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+  BrowserThread::PostTask(
+      BrowserThread::IO,
+      FROM_HERE,
+      base::Bind(&ImageWriterClient::Shutdown, image_writer_client_));
+}
+
+void Operation::WriteImageProgress(int64 total_bytes, int64 curr_bytes) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
   if (IsCancelled()) {
     return;
   }
 
-  DVLOG(1) << "Starting unzip stage for " << zip_path->value();
+  int progress = kProgressComplete * curr_bytes / total_bytes;

[Lei Zhang, 2014/02/15 00:26:59]

Can this overflow? Same with line 338.

[Drew Haven, 2014/02/15 01:23:58]

My understanding is that kProgressComplete * curr_bytes will be in64.  Since
kProgressComplete is 100 this shouldn't overflow for any file size we'd
realistically encounter.  Then we divide by the total_bytes, with curr_bytes <
total_bytes (though maybe that should be asserted in some way) and so the result
should always been in [0,100].

[Lei Zhang, 2014/02/15 01:41:50]

Do you trust the utility process to send you a valid |curr_bytes| ? If yes, then
ok. For some utility processes, such as parsers, we certainly don't trust them
because the parser code may have bugs. In this case,  I think you are separating
the code into the utility mostly for privilege escalation, so otherwise this
would be browser code that you' d trust.

[Jorge Lucangeli Obes, 2014/02/15 01:43:19]

I would add CHECKS for both values to be positive, and curr_bytes < total_bytes.

+
+  if (progress > GetProgress()) {
+    SetProgress(progress);
+  }
+}
+
+void Operation::UnzipStart(scoped_ptr<base::FilePath> zip_path) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+  if (IsCancelled()) {
+    return;
+  }
 
   SetStage(image_writer_api::STAGE_UNZIP);
 
@@ -335,7 +360,7 @@ void Operation::OnUnzipFailure() {
 void Operation::OnUnzipProgress(int64 total_bytes, int64 progress_bytes) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
-  int progress_percent = 100 * progress_bytes / total_bytes;
+  int progress_percent = kProgressComplete * progress_bytes / total_bytes;
   SetProgress(progress_percent);
 }