src/chrome/browser/extensions/api/music_manager_private/device_id_linux.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/extensions/api/music_manager_private/device_id.h"
   6
   7 #include <map>
   8
   9 #include "base/bind.h"
  10 #include "base/file_util.h"
  11 #include "base/files/file_enumerator.h"
  12 #include "base/files/file_path.h"
  13 #include "base/threading/thread_restrictions.h"
  14 #include "content/public/browser/browser_thread.h"
  15
  16 namespace {
  17
  18 const char kDiskByUuidDirectoryName[] = "/dev/disk/by-uuid";
  19 const char* kDeviceNames[] = {
  20   "sda1", "hda1", "dm-0", "xvda1", "sda2", "hda2", "dm-1", "xvda2",
  21 };
  22
  23 // Map from device name to disk uuid
  24 typedef std::map<base::FilePath, base::FilePath> DiskEntries;
  25
  26 void GetDiskUuid(const extensions::api::DeviceId::IdCallback& callback) {
  27   base::ThreadRestrictions::AssertIOAllowed();
  28
  29   DiskEntries disk_uuids;
  30   base::FileEnumerator files(base::FilePath(kDiskByUuidDirectoryName),
  31                              false,  // Recursive.
  32                              base::FileEnumerator::FILES);
  33   do {
  34     base::FilePath file_path = files.Next();
  35     if (file_path.empty())
  36       break;
  37
  38     base::FilePath target_path;
  39     if (!base::ReadSymbolicLink(file_path, &target_path))
  40       continue;
  41
  42     base::FilePath device_name = target_path.BaseName();
  43     base::FilePath disk_uuid = file_path.BaseName();
  44     disk_uuids[device_name] = disk_uuid;
  45   } while (true);
  46
  47   // Look for first device name matching an entry of |kDeviceNames|.
  48   std::string result;
  49   for (size_t i = 0; i < arraysize(kDeviceNames); i++) {
  50     DiskEntries::iterator it =
  51         disk_uuids.find(base::FilePath(kDeviceNames[i]));
  52     if (it != disk_uuids.end()) {
  53       DVLOG(1) << "Returning uuid: \"" << it->second.value()
  54                << "\" for device \"" << it->first.value() << "\"";
  55       result = it->second.value();
  56       break;
  57     }
  58   }
  59
  60   // Log failure (at most once) for diagnostic purposes.
  61   static bool error_logged = false;
  62   if (result.empty() && !error_logged) {
  63     error_logged = true;
  64     LOG(ERROR) << "Could not find appropriate disk uuid.";
  65     for (DiskEntries::iterator it = disk_uuids.begin();
  66         it != disk_uuids.end(); ++it) {
  67       LOG(ERROR) << "  DeviceID=" << it->first.value() << ", uuid="
  68                  << it->second.value();
  69     }
  70   }
  71
  72   content::BrowserThread::PostTask(
  73       content::BrowserThread::UI,
  74       FROM_HERE,
  75       base::Bind(callback, result));
  76 }
  77
  78 }  // namespace
  79
  80 namespace extensions {
  81 namespace api {
  82
  83 // static
  84 void DeviceId::GetRawDeviceId(const IdCallback& callback) {
  85   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
  86
  87   content::BrowserThread::PostTask(
  88       content::BrowserThread::FILE,
  89       FROM_HERE,
  90       base::Bind(GetDiskUuid, callback));
  91 }
  92
  93 }  // namespace api
  94 }  // namespace extensions