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      1 //
      2 // Copyright (C) 2012 The Android Open Source Project
      3 //
      4 // Licensed under the Apache License, Version 2.0 (the "License");
      5 // you may not use this file except in compliance with the License.
      6 // You may obtain a copy of the License at
      7 //
      8 //      http://www.apache.org/licenses/LICENSE-2.0
      9 //
     10 // Unless required by applicable law or agreed to in writing, software
     11 // distributed under the License is distributed on an "AS IS" BASIS,
     12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13 // See the License for the specific language governing permissions and
     14 // limitations under the License.
     15 //
     16 
     17 #include "update_engine/p2p_manager.h"
     18 
     19 #include <dirent.h>
     20 #include <fcntl.h>
     21 #include <sys/stat.h>
     22 #include <sys/types.h>
     23 #include <sys/xattr.h>
     24 #include <unistd.h>
     25 
     26 #include <memory>
     27 #include <string>
     28 #include <vector>
     29 
     30 #include <base/bind.h>
     31 #include <base/callback.h>
     32 #include <base/files/file_util.h>
     33 #include <base/message_loop/message_loop.h>
     34 #include <base/strings/stringprintf.h>
     35 #include <brillo/asynchronous_signal_handler.h>
     36 #include <brillo/message_loops/base_message_loop.h>
     37 #include <brillo/message_loops/message_loop.h>
     38 #include <brillo/message_loops/message_loop_utils.h>
     39 #include <gmock/gmock.h>
     40 #include <gtest/gtest.h>
     41 #include <policy/libpolicy.h>
     42 #include <policy/mock_device_policy.h>
     43 
     44 #include "update_engine/common/fake_clock.h"
     45 #include "update_engine/common/prefs.h"
     46 #include "update_engine/common/test_utils.h"
     47 #include "update_engine/common/utils.h"
     48 #include "update_engine/fake_p2p_manager_configuration.h"
     49 #include "update_engine/update_manager/fake_update_manager.h"
     50 #include "update_engine/update_manager/mock_policy.h"
     51 
     52 using base::TimeDelta;
     53 using brillo::MessageLoop;
     54 using std::string;
     55 using std::unique_ptr;
     56 using std::vector;
     57 using testing::DoAll;
     58 using testing::Return;
     59 using testing::SetArgPointee;
     60 using testing::_;
     61 
     62 namespace chromeos_update_engine {
     63 
     64 // Test fixture that sets up a testing configuration (with e.g. a
     65 // temporary p2p dir) for P2PManager and cleans up when the test is
     66 // done.
     67 class P2PManagerTest : public testing::Test {
     68  protected:
     69   P2PManagerTest() : fake_um_(&fake_clock_) {}
     70   ~P2PManagerTest() override {}
     71 
     72   // Derived from testing::Test.
     73   void SetUp() override {
     74     loop_.SetAsCurrent();
     75     async_signal_handler_.Init();
     76     subprocess_.Init(&async_signal_handler_);
     77     test_conf_ = new FakeP2PManagerConfiguration();
     78 
     79     // Allocate and install a mock policy implementation in the fake Update
     80     // Manager.  Note that the FakeUpdateManager takes ownership of the policy
     81     // object.
     82     mock_policy_ = new chromeos_update_manager::MockPolicy(&fake_clock_);
     83     fake_um_.set_policy(mock_policy_);
     84 
     85     // Construct the P2P manager under test.
     86     manager_.reset(P2PManager::Construct(test_conf_, &fake_clock_, &fake_um_,
     87                                          "cros_au", 3,
     88                                          TimeDelta::FromDays(5)));
     89   }
     90 
     91   base::MessageLoopForIO base_loop_;
     92   brillo::BaseMessageLoop loop_{&base_loop_};
     93   brillo::AsynchronousSignalHandler async_signal_handler_;
     94   Subprocess subprocess_;
     95 
     96   // The P2PManager::Configuration instance used for testing.
     97   FakeP2PManagerConfiguration *test_conf_;
     98 
     99   FakeClock fake_clock_;
    100   chromeos_update_manager::MockPolicy *mock_policy_ = nullptr;
    101   chromeos_update_manager::FakeUpdateManager fake_um_;
    102 
    103   unique_ptr<P2PManager> manager_;
    104 };
    105 
    106 
    107 // Check that IsP2PEnabled() polls the policy correctly, with the value not
    108 // changing between calls.
    109 TEST_F(P2PManagerTest, P2PEnabledInitAndNotChanged) {
    110   EXPECT_CALL(*mock_policy_, P2PEnabled(_, _, _, _));
    111   EXPECT_CALL(*mock_policy_, P2PEnabledChanged(_, _, _, _, false));
    112 
    113   EXPECT_FALSE(manager_->IsP2PEnabled());
    114   brillo::MessageLoopRunMaxIterations(MessageLoop::current(), 100);
    115   EXPECT_FALSE(manager_->IsP2PEnabled());
    116 }
    117 
    118 // Check that IsP2PEnabled() polls the policy correctly, with the value changing
    119 // between calls.
    120 TEST_F(P2PManagerTest, P2PEnabledInitAndChanged) {
    121   EXPECT_CALL(*mock_policy_, P2PEnabled(_, _, _, _))
    122       .WillOnce(DoAll(
    123               SetArgPointee<3>(true),
    124               Return(chromeos_update_manager::EvalStatus::kSucceeded)));
    125   EXPECT_CALL(*mock_policy_, P2PEnabledChanged(_, _, _, _, true));
    126   EXPECT_CALL(*mock_policy_, P2PEnabledChanged(_, _, _, _, false));
    127 
    128   EXPECT_TRUE(manager_->IsP2PEnabled());
    129   brillo::MessageLoopRunMaxIterations(MessageLoop::current(), 100);
    130   EXPECT_FALSE(manager_->IsP2PEnabled());
    131 }
    132 
    133 // Check that we keep the $N newest files with the .$EXT.p2p extension.
    134 TEST_F(P2PManagerTest, HousekeepingCountLimit) {
    135   // Specifically pass 0 for |max_file_age| to allow files of any age. Note that
    136   // we need to reallocate the test_conf_ member, whose currently aliased object
    137   // will be freed.
    138   test_conf_ = new FakeP2PManagerConfiguration();
    139   manager_.reset(P2PManager::Construct(
    140       test_conf_, &fake_clock_, &fake_um_, "cros_au", 3,
    141       TimeDelta() /* max_file_age */));
    142   EXPECT_EQ(manager_->CountSharedFiles(), 0);
    143 
    144   base::Time start_time = base::Time::FromDoubleT(1246996800.);
    145   // Generate files with different timestamps matching our pattern and generate
    146   // other files not matching the pattern.
    147   for (int n = 0; n < 5; n++) {
    148     base::FilePath path = test_conf_->GetP2PDir().Append(base::StringPrintf(
    149         "file_%d.cros_au.p2p", n));
    150     base::Time file_time = start_time + TimeDelta::FromMinutes(n);
    151     EXPECT_EQ(0, base::WriteFile(path, nullptr, 0));
    152     EXPECT_TRUE(base::TouchFile(path, file_time, file_time));
    153 
    154     path = test_conf_->GetP2PDir().Append(base::StringPrintf(
    155         "file_%d.OTHER.p2p", n));
    156     EXPECT_EQ(0, base::WriteFile(path, nullptr, 0));
    157     EXPECT_TRUE(base::TouchFile(path, file_time, file_time));
    158   }
    159   // CountSharedFiles() only counts 'cros_au' files.
    160   EXPECT_EQ(manager_->CountSharedFiles(), 5);
    161 
    162   EXPECT_TRUE(manager_->PerformHousekeeping());
    163 
    164   // At this point - after HouseKeeping - we should only have
    165   // eight files left.
    166   for (int n = 0; n < 5; n++) {
    167     string file_name;
    168     bool expect;
    169 
    170     expect = (n >= 2);
    171     file_name = base::StringPrintf(
    172         "%s/file_%d.cros_au.p2p",
    173          test_conf_->GetP2PDir().value().c_str(), n);
    174     EXPECT_EQ(expect, utils::FileExists(file_name.c_str()));
    175 
    176     file_name = base::StringPrintf(
    177         "%s/file_%d.OTHER.p2p",
    178         test_conf_->GetP2PDir().value().c_str(), n);
    179     EXPECT_TRUE(utils::FileExists(file_name.c_str()));
    180   }
    181   // CountSharedFiles() only counts 'cros_au' files.
    182   EXPECT_EQ(manager_->CountSharedFiles(), 3);
    183 }
    184 
    185 // Check that we keep files with the .$EXT.p2p extension not older
    186 // than some specificed age (5 days, in this test).
    187 TEST_F(P2PManagerTest, HousekeepingAgeLimit) {
    188   // We set the cutoff time to be 1 billion seconds (01:46:40 UTC on 9
    189   // September 2001 - arbitrary number, but constant to avoid test
    190   // flakiness) since the epoch and then we put two files before that
    191   // date and three files after.
    192   base::Time cutoff_time = base::Time::FromTimeT(1000000000);
    193   TimeDelta age_limit = TimeDelta::FromDays(5);
    194 
    195   // Set the clock just so files with a timestamp before |cutoff_time|
    196   // will be deleted at housekeeping.
    197   fake_clock_.SetWallclockTime(cutoff_time + age_limit);
    198 
    199   // Specifically pass 0 for |num_files_to_keep| to allow any number of files.
    200   // Note that we need to reallocate the test_conf_ member, whose currently
    201   // aliased object will be freed.
    202   test_conf_ = new FakeP2PManagerConfiguration();
    203   manager_.reset(P2PManager::Construct(
    204       test_conf_, &fake_clock_, &fake_um_, "cros_au",
    205       0 /* num_files_to_keep */, age_limit));
    206   EXPECT_EQ(manager_->CountSharedFiles(), 0);
    207 
    208   // Generate files with different timestamps matching our pattern and generate
    209   // other files not matching the pattern.
    210   for (int n = 0; n < 5; n++) {
    211     base::FilePath path = test_conf_->GetP2PDir().Append(base::StringPrintf(
    212         "file_%d.cros_au.p2p", n));
    213 
    214     // With five files and aiming for two of them to be before
    215     // |cutoff_time|, we distribute it like this:
    216     //
    217     //  -------- 0 -------- 1 -------- 2 -------- 3 -------- 4 --------
    218     //                            |
    219     //                       cutoff_time
    220     //
    221     base::Time file_date = cutoff_time + (n - 2) * TimeDelta::FromDays(1)
    222         + TimeDelta::FromHours(12);
    223 
    224     EXPECT_EQ(0, base::WriteFile(path, nullptr, 0));
    225     EXPECT_TRUE(base::TouchFile(path, file_date, file_date));
    226 
    227     path = test_conf_->GetP2PDir().Append(base::StringPrintf(
    228         "file_%d.OTHER.p2p", n));
    229     EXPECT_EQ(0, base::WriteFile(path, nullptr, 0));
    230     EXPECT_TRUE(base::TouchFile(path, file_date, file_date));
    231   }
    232   // CountSharedFiles() only counts 'cros_au' files.
    233   EXPECT_EQ(manager_->CountSharedFiles(), 5);
    234 
    235   EXPECT_TRUE(manager_->PerformHousekeeping());
    236 
    237   // At this point - after HouseKeeping - we should only have
    238   // eight files left.
    239   for (int n = 0; n < 5; n++) {
    240     string file_name;
    241     bool expect;
    242 
    243     expect = (n >= 2);
    244     file_name = base::StringPrintf(
    245         "%s/file_%d.cros_au.p2p",
    246          test_conf_->GetP2PDir().value().c_str(), n);
    247     EXPECT_EQ(expect, utils::FileExists(file_name.c_str()));
    248 
    249     file_name = base::StringPrintf(
    250         "%s/file_%d.OTHER.p2p",
    251         test_conf_->GetP2PDir().value().c_str(), n);
    252     EXPECT_TRUE(utils::FileExists(file_name.c_str()));
    253   }
    254   // CountSharedFiles() only counts 'cros_au' files.
    255   EXPECT_EQ(manager_->CountSharedFiles(), 3);
    256 }
    257 
    258 static bool CheckP2PFile(const string& p2p_dir, const string& file_name,
    259                          ssize_t expected_size, ssize_t expected_size_xattr) {
    260   string path = p2p_dir + "/" + file_name;
    261   char ea_value[64] = { 0 };
    262   ssize_t ea_size;
    263 
    264   off_t p2p_size = utils::FileSize(path);
    265   if (p2p_size < 0) {
    266     LOG(ERROR) << "File " << path << " does not exist";
    267     return false;
    268   }
    269 
    270   if (expected_size != 0) {
    271     if (p2p_size != expected_size) {
    272       LOG(ERROR) << "Expected size " << expected_size
    273                  << " but size was " << p2p_size;
    274       return false;
    275     }
    276   }
    277 
    278   if (expected_size_xattr == 0) {
    279     ea_size = getxattr(path.c_str(), "user.cros-p2p-filesize",
    280                        &ea_value, sizeof ea_value - 1);
    281     if (ea_size == -1 && errno == ENODATA) {
    282       // This is valid behavior as we support files without the xattr set.
    283     } else {
    284       PLOG(ERROR) << "getxattr() didn't fail with ENODATA as expected, "
    285                   << "ea_size=" << ea_size << ", errno=" << errno;
    286       return false;
    287     }
    288   } else {
    289     ea_size = getxattr(path.c_str(), "user.cros-p2p-filesize",
    290                        &ea_value, sizeof ea_value - 1);
    291     if (ea_size < 0) {
    292       LOG(ERROR) << "Error getting xattr attribute";
    293       return false;
    294     }
    295     char* endp = nullptr;
    296     long long int val = strtoll(ea_value, &endp, 0);  // NOLINT(runtime/int)
    297     if (endp == nullptr || *endp != '\0') {
    298       LOG(ERROR) << "Error parsing xattr '" << ea_value
    299                  << "' as an integer";
    300       return false;
    301     }
    302     if (val != expected_size_xattr) {
    303       LOG(ERROR) << "Expected xattr size " << expected_size_xattr
    304                  << " but size was " << val;
    305       return false;
    306     }
    307   }
    308 
    309   return true;
    310 }
    311 
    312 static bool CreateP2PFile(string p2p_dir, string file_name,
    313                           size_t size, size_t size_xattr) {
    314   string path = p2p_dir + "/" + file_name;
    315 
    316   int fd = open(path.c_str(), O_CREAT|O_RDWR, 0644);
    317   if (fd == -1) {
    318     PLOG(ERROR) << "Error creating file with path " << path;
    319     return false;
    320   }
    321   if (ftruncate(fd, size) != 0) {
    322     PLOG(ERROR) << "Error truncating " << path << " to size " << size;
    323     close(fd);
    324     return false;
    325   }
    326 
    327   if (size_xattr != 0) {
    328     string decimal_size = std::to_string(size_xattr);
    329     if (fsetxattr(fd, "user.cros-p2p-filesize",
    330                   decimal_size.c_str(), decimal_size.size(), 0) != 0) {
    331       PLOG(ERROR) << "Error setting xattr on " << path;
    332       close(fd);
    333       return false;
    334     }
    335   }
    336 
    337   close(fd);
    338   return true;
    339 }
    340 
    341 // Check that sharing a *new* file works.
    342 TEST_F(P2PManagerTest, ShareFile) {
    343   if (!test_utils::IsXAttrSupported(base::FilePath("/tmp"))) {
    344     LOG(WARNING) << "Skipping test because /tmp does not support xattr. "
    345                  << "Please update your system to support this feature.";
    346     return;
    347   }
    348   const int kP2PTestFileSize = 1000 * 1000;  // 1 MB
    349 
    350   EXPECT_TRUE(manager_->FileShare("foo", kP2PTestFileSize));
    351   EXPECT_EQ(manager_->FileGetPath("foo"),
    352             test_conf_->GetP2PDir().Append("foo.cros_au.p2p.tmp"));
    353   EXPECT_TRUE(CheckP2PFile(test_conf_->GetP2PDir().value(),
    354                            "foo.cros_au.p2p.tmp", 0, kP2PTestFileSize));
    355 
    356   // Sharing it again - with the same expected size - should return true
    357   EXPECT_TRUE(manager_->FileShare("foo", kP2PTestFileSize));
    358 
    359   // ... but if we use the wrong size, it should fail
    360   EXPECT_FALSE(manager_->FileShare("foo", kP2PTestFileSize + 1));
    361 }
    362 
    363 // Check that making a shared file visible, does what is expected.
    364 TEST_F(P2PManagerTest, MakeFileVisible) {
    365   if (!test_utils::IsXAttrSupported(base::FilePath("/tmp"))) {
    366     LOG(WARNING) << "Skipping test because /tmp does not support xattr. "
    367                  << "Please update your system to support this feature.";
    368     return;
    369   }
    370   const int kP2PTestFileSize = 1000 * 1000;  // 1 MB
    371 
    372   // First, check that it's not visible.
    373   manager_->FileShare("foo", kP2PTestFileSize);
    374   EXPECT_EQ(manager_->FileGetPath("foo"),
    375             test_conf_->GetP2PDir().Append("foo.cros_au.p2p.tmp"));
    376   EXPECT_TRUE(CheckP2PFile(test_conf_->GetP2PDir().value(),
    377                            "foo.cros_au.p2p.tmp", 0, kP2PTestFileSize));
    378   // Make the file visible and check that it changed its name. Do it
    379   // twice to check that FileMakeVisible() is idempotent.
    380   for (int n = 0; n < 2; n++) {
    381     manager_->FileMakeVisible("foo");
    382     EXPECT_EQ(manager_->FileGetPath("foo"),
    383               test_conf_->GetP2PDir().Append("foo.cros_au.p2p"));
    384     EXPECT_TRUE(CheckP2PFile(test_conf_->GetP2PDir().value(),
    385                              "foo.cros_au.p2p", 0, kP2PTestFileSize));
    386   }
    387 }
    388 
    389 // Check that we return the right values for existing files in P2P_DIR.
    390 TEST_F(P2PManagerTest, ExistingFiles) {
    391   if (!test_utils::IsXAttrSupported(base::FilePath("/tmp"))) {
    392     LOG(WARNING) << "Skipping test because /tmp does not support xattr. "
    393                  << "Please update your system to support this feature.";
    394     return;
    395   }
    396 
    397   bool visible;
    398 
    399   // Check that errors are returned if the file does not exist
    400   EXPECT_EQ(manager_->FileGetPath("foo"), base::FilePath());
    401   EXPECT_EQ(manager_->FileGetSize("foo"), -1);
    402   EXPECT_EQ(manager_->FileGetExpectedSize("foo"), -1);
    403   EXPECT_FALSE(manager_->FileGetVisible("foo", nullptr));
    404   // ... then create the file ...
    405   EXPECT_TRUE(CreateP2PFile(test_conf_->GetP2PDir().value(),
    406                             "foo.cros_au.p2p", 42, 43));
    407   // ... and then check that the expected values are returned
    408   EXPECT_EQ(manager_->FileGetPath("foo"),
    409             test_conf_->GetP2PDir().Append("foo.cros_au.p2p"));
    410   EXPECT_EQ(manager_->FileGetSize("foo"), 42);
    411   EXPECT_EQ(manager_->FileGetExpectedSize("foo"), 43);
    412   EXPECT_TRUE(manager_->FileGetVisible("foo", &visible));
    413   EXPECT_TRUE(visible);
    414 
    415   // One more time, this time with a .tmp variant. First ensure it errors out..
    416   EXPECT_EQ(manager_->FileGetPath("bar"), base::FilePath());
    417   EXPECT_EQ(manager_->FileGetSize("bar"), -1);
    418   EXPECT_EQ(manager_->FileGetExpectedSize("bar"), -1);
    419   EXPECT_FALSE(manager_->FileGetVisible("bar", nullptr));
    420   // ... then create the file ...
    421   EXPECT_TRUE(CreateP2PFile(test_conf_->GetP2PDir().value(),
    422                             "bar.cros_au.p2p.tmp", 44, 45));
    423   // ... and then check that the expected values are returned
    424   EXPECT_EQ(manager_->FileGetPath("bar"),
    425             test_conf_->GetP2PDir().Append("bar.cros_au.p2p.tmp"));
    426   EXPECT_EQ(manager_->FileGetSize("bar"), 44);
    427   EXPECT_EQ(manager_->FileGetExpectedSize("bar"), 45);
    428   EXPECT_TRUE(manager_->FileGetVisible("bar", &visible));
    429   EXPECT_FALSE(visible);
    430 }
    431 
    432 // This is a little bit ugly but short of mocking a 'p2p' service this
    433 // will have to do. E.g. we essentially simulate the various
    434 // behaviours of initctl(8) that we rely on.
    435 TEST_F(P2PManagerTest, StartP2P) {
    436   // Check that we can start the service
    437   test_conf_->SetInitctlStartCommand({"true"});
    438   EXPECT_TRUE(manager_->EnsureP2PRunning());
    439   test_conf_->SetInitctlStartCommand({"false"});
    440   EXPECT_FALSE(manager_->EnsureP2PRunning());
    441   test_conf_->SetInitctlStartCommand({
    442       "sh", "-c", "echo \"initctl: Job is already running: p2p\" >&2; false"});
    443   EXPECT_TRUE(manager_->EnsureP2PRunning());
    444   test_conf_->SetInitctlStartCommand({
    445       "sh", "-c", "echo something else >&2; false"});
    446   EXPECT_FALSE(manager_->EnsureP2PRunning());
    447 }
    448 
    449 // Same comment as for StartP2P
    450 TEST_F(P2PManagerTest, StopP2P) {
    451   // Check that we can start the service
    452   test_conf_->SetInitctlStopCommand({"true"});
    453   EXPECT_TRUE(manager_->EnsureP2PNotRunning());
    454   test_conf_->SetInitctlStopCommand({"false"});
    455   EXPECT_FALSE(manager_->EnsureP2PNotRunning());
    456   test_conf_->SetInitctlStopCommand({
    457       "sh", "-c", "echo \"initctl: Unknown instance \" >&2; false"});
    458   EXPECT_TRUE(manager_->EnsureP2PNotRunning());
    459   test_conf_->SetInitctlStopCommand({
    460       "sh", "-c", "echo something else >&2; false"});
    461   EXPECT_FALSE(manager_->EnsureP2PNotRunning());
    462 }
    463 
    464 static void ExpectUrl(const string& expected_url,
    465                       const string& url) {
    466   EXPECT_EQ(url, expected_url);
    467   MessageLoop::current()->BreakLoop();
    468 }
    469 
    470 // Like StartP2P, we're mocking the different results that p2p-client
    471 // can return. It's not pretty but it works.
    472 TEST_F(P2PManagerTest, LookupURL) {
    473   // Emulate p2p-client returning valid URL with "fooX", 42 and "cros_au"
    474   // being propagated in the right places.
    475   test_conf_->SetP2PClientCommand({
    476       "echo", "http://1.2.3.4/{file_id}_{minsize}"});
    477   manager_->LookupUrlForFile("fooX", 42, TimeDelta(),
    478                              base::Bind(ExpectUrl,
    479                                         "http://1.2.3.4/fooX.cros_au_42"));
    480   loop_.Run();
    481 
    482   // Emulate p2p-client returning invalid URL.
    483   test_conf_->SetP2PClientCommand({"echo", "not_a_valid_url"});
    484   manager_->LookupUrlForFile("foobar", 42, TimeDelta(),
    485                              base::Bind(ExpectUrl, ""));
    486   loop_.Run();
    487 
    488   // Emulate p2p-client conveying failure.
    489   test_conf_->SetP2PClientCommand({"false"});
    490   manager_->LookupUrlForFile("foobar", 42, TimeDelta(),
    491                              base::Bind(ExpectUrl, ""));
    492   loop_.Run();
    493 
    494   // Emulate p2p-client not existing.
    495   test_conf_->SetP2PClientCommand({"/path/to/non/existent/helper/program"});
    496   manager_->LookupUrlForFile("foobar", 42,
    497                              TimeDelta(),
    498                              base::Bind(ExpectUrl, ""));
    499   loop_.Run();
    500 
    501   // Emulate p2p-client crashing.
    502   test_conf_->SetP2PClientCommand({"sh", "-c", "kill -SEGV $$"});
    503   manager_->LookupUrlForFile("foobar", 42, TimeDelta(),
    504                              base::Bind(ExpectUrl, ""));
    505   loop_.Run();
    506 
    507   // Emulate p2p-client exceeding its timeout.
    508   test_conf_->SetP2PClientCommand({
    509       "sh", "-c", "echo http://1.2.3.4/; sleep 2"});
    510   manager_->LookupUrlForFile("foobar", 42, TimeDelta::FromMilliseconds(500),
    511                              base::Bind(ExpectUrl, ""));
    512   loop_.Run();
    513 }
    514 
    515 }  // namespace chromeos_update_engine
    516