Deliver attach intent to packaged apps

chrome/browser/media_gallery/media_storage_util.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.
 
 // chrome::MediaStorageUtil implementation.
 
 #include "chrome/browser/media_gallery/media_storage_util.h"
 
 #include <vector>
 
@@ skipping 84 matching lines @@
       return std::string(kUsbMtpPrefix) + unique_id;
   }
   NOTREACHED();
   return std::string();
 }
 
 // static
 bool MediaStorageUtil::CrackDeviceId(const std::string& device_id,
                                      Type* type, std::string* unique_id) {
   size_t prefix_length = device_id.find_first_of(':');
-  std::string prefix = device_id.substr(0, prefix_length);
+  std::string prefix;
+  if (prefix_length != std::string::npos) {

[benwells, 2012/08/28 08:50:51]

Are there instances where there are no colons in the device ID? Could you add a
comment about why this happens?

[thorogood, 2012/08/28 23:48:11]

I don't believe so. The device_id is only something we build internally (where
we guarantee it contains a colon), pass around, and then want to crack apart
again - it's not persisted or anything.

Note that this was previously a bug - all the prefix types (e.g.,
kUsbMassStorageNoDCIMPrefix) contain the colon, so the prefix we were obtaining
didn't contain that, and we'd always hit NOTREACHED below.

The check (the if statement) is mostly because we search for the colon, but grab
a character past that, so that would be bad if we were at std::string::npos...

I've added a short comment for clarification.

+    prefix = device_id.substr(0, prefix_length + 1);
+  }
 
   Type found_type;
   if (prefix == kUsbMassStorageWithDCIMPrefix) {
     found_type = USB_MASS_STORAGE_WITH_DCIM;
   } else if (prefix == kUsbMassStorageNoDCIMPrefix) {
     found_type = USB_MASS_STORAGE_NO_DCIM;
   } else if (prefix == kOtherMassStoragePrefix) {
     found_type = OTHER_MASS_STORAGE;
   } else if (prefix == kUsbMtpPrefix) {
     found_type = USB_MTP;
@@ skipping 108 matching lines @@
 void MediaStorageUtil::FindUSBDeviceById(const std::string& unique_id,
                                          const FilePathCallback& callback) {
   // TODO(vandebo) This needs to be implemented per platform.
   // Type is USB_MASS_STORAGE_NO_DCIM, so it's a device possibly mounted
   // somewhere...
   NOTREACHED();
   callback.Run(FilePath());
 }
 
 }  // namespace chrome