Detect removed files and reflect the state in chrome://downloads and the download shelf

chrome/browser/download/download_manager.cc

 // Copyright (c) 2011 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 "chrome/browser/download/download_manager.h"
 
 #include "base/callback.h"
 #include "base/file_util.h"
 #include "base/i18n/case_conversion.h"
 #include "base/logging.h"
@@ skipping 247 matching lines @@
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   // Create a client to verify download URL with safebrowsing.
   // It deletes itself after the callback.
   scoped_refptr<DownloadSBClient> sb_client = new DownloadSBClient(
       info->download_id, info->url_chain, info->referrer_url);
   sb_client->CheckDownloadUrl(
       info, NewCallback(this, &DownloadManager::CheckDownloadUrlDone));
 }
 
+void DownloadManager::CheckForFilesRemoval() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  for (DownloadMap::iterator it = history_downloads_.begin();
+       it != history_downloads_.end(); ++it) {
+    DownloadItem* download_item = it->second;
+    if (download_item->IsComplete() && download_item->file_exists()) {
+        BrowserThread::PostTask(
+            BrowserThread::FILE, FROM_HERE,
+            NewRunnableMethod(this,
+                &DownloadManager::CheckForFilesRemovalOnFileThread,
+                it->first, download_item->GetTargetFilePath()));
+    }
+  }
+}
+
+void DownloadManager::CheckForFilesRemovalOnFileThread(
+    int64 db_handle, const FilePath& path) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+  bool file_exists = file_util::PathExists(path);
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      NewRunnableMethod(this,
+                        &DownloadManager::OnFilesRemovalDetected,
+                        db_handle, file_exists));
+}
+
+void DownloadManager::OnFilesRemovalDetected(

[Randy Smith (Not in Mondays), 2011/05/12 20:21:17]

Given that we're doing single file checks now, we should change the plural in
the name to a singular (Files->File).

[haraken1, 2011/05/13 14:08:17]

Done.

+    int64 db_handle, bool file_exists) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!file_exists) {

[Randy Smith (Not in Mondays), 2011/05/12 20:21:17]

Given that this function doesn't do anything if file_exists is false, how about
removing that argument from the function signature and not sending the response
message from the file thread if the file is still there?

[haraken1, 2011/05/13 14:08:17]

Done.

+    DownloadMap::iterator it = history_downloads_.find(db_handle);
+    if (it != history_downloads_.end()) {
+      DownloadItem* download_item = it->second;
+      download_item->OnDownloadedFileRemoved();
+    }
+  }
+}
+
 void DownloadManager::CheckDownloadUrlDone(DownloadCreateInfo* info,
                                            bool is_dangerous_url) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(info);
 
   info->is_dangerous_url = is_dangerous_url;
 
   // Check whether this download is for an extension install or not.
   // Allow extensions to be explicitly saved.
   if (!info->prompt_user_for_save_location) {
@@ skipping 897 matching lines @@
     observed_download_manager_->RemoveObserver(this);
 }
 
 void DownloadManager::OtherDownloadManagerObserver::ModelChanged() {
   observing_download_manager_->NotifyModelChanged();
 }
 
 void DownloadManager::OtherDownloadManagerObserver::ManagerGoingDown() {
   observed_download_manager_ = NULL;
 }