Fix file access on Chrome for ChromeOS on Linux

net/url_request/url_request_file_job.cc

 // Copyright (c) 2012 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.
 
 // For loading files, we make use of overlapped i/o to ensure that reading from
 // the filesystem (e.g., a network filesystem) does not block the calling
 // thread.  An alternative approach would be to use a background thread or pool
 // of threads, but it seems better to leverage the operating system's ability
 // to do background file reads for us.
 //
 // Since overlapped reads require a 'static' buffer for the duration of the
 // asynchronous read, the URLRequestFileJob keeps a buffer as a member var.  In
 // URLRequestFileJob::Read, data is simply copied from the object's buffer into
 // the given buffer.  If there is no data to copy, the URLRequestFileJob
 // attempts to read more from the file to fill its buffer.  If reading from the
 // file does not complete synchronously, then the URLRequestFileJob waits for a
 // signal from the OS that the overlapped read has completed.  It does so by
 // leveraging the MessageLoop::WatchObject API.
 
 #include "net/url_request/url_request_file_job.h"
 
 #include "base/bind.h"
+#include "base/chromeos/chromeos_version.h"
 #include "base/compiler_specific.h"
 #include "base/message_loop.h"
 #include "base/platform_file.h"
 #include "base/string_util.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/worker_pool.h"
 #include "base/threading/thread_restrictions.h"
 #include "build/build_config.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/io_buffer.h"
@@ skipping 97 matching lines @@
   "/tmp",
   "/var/log",
 };
 
 // static
 bool URLRequestFileJob::AccessDisabled(const FilePath& file_path) {
   if (URLRequest::IsFileAccessAllowed()) {  // for tests.
     return false;
   }
 
+  // If we're running Chrome for ChromeOS on Linux, we want to allow files

[zel, 2012/04/12 20:19:40]

if this is for debugging only on Linux machines with ChromeOS build. I would 

#if defined(OS_CHROMEOS)
#ifndef NDEBUG
...
#endif
#endif

[Greg Spencer (Chromium), 2012/04/12 20:26:58]

It's already inside of OS_CHROMEOS, and while I see what you're saying, I think
that making it available to release would be less annoying for a future
developer wondering why they can't access a file on their (release) build, even
though they can see it in the file selection dialog: they might spend time
trying to track it down as a bug.

[willchan no longer on Chromium, 2012/04/12 23:44:59]

Ugh, I don't know why this whitelist was allowed in the first place. This stuff
is all layering violations. net/ shouldn't know anything about chromeos
filesystem kinda stuff. Is there any other way to accomplish it?

+  // within the user's Downloads directory.
+  if (!base::chromeos::IsRunningOnChromeOS()) {
+    const char* home = getenv("HOME");
+    if (home && strlen(home) > 0) {
+      FilePath home_path(home);
+      home_path.AppendASCII("Downloads");
+      if (home_path.IsParent(file_path))
+        return false;
+    }
+  }
+
   for (size_t i = 0; i < arraysize(kLocalAccessWhiteList); ++i) {
     const FilePath white_listed_path(kLocalAccessWhiteList[i]);
     // FilePath::operator== should probably handle trailing seperators.
     if (white_listed_path == file_path.StripTrailingSeparators() ||
         white_listed_path.IsParent(file_path)) {
       return false;
     }
   }
   return true;
 }
@@ skipping 210 matching lines @@
     NotifyDone(URLRequestStatus(URLRequestStatus::FAILED, result));
   }
 
   remaining_bytes_ -= result;
   DCHECK_GE(remaining_bytes_, 0);
 
   NotifyReadComplete(result);
 }
 
 }  // namespace net