src/chrome/browser/devtools/devtools_file_system_indexer.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/devtools/devtools_file_system_indexer.h"
   6
   7 #include <iterator>
   8
   9 #include "base/bind.h"
  10 #include "base/callback.h"
  11 #include "base/files/file_enumerator.h"
  12 #include "base/files/file_util.h"
  13 #include "base/files/file_util_proxy.h"
  14 #include "base/lazy_instance.h"
  15 #include "base/logging.h"
  16 #include "base/stl_util.h"
  17 #include "base/strings/utf_string_conversions.h"
  18 #include "content/public/browser/browser_thread.h"
  19
  20 using base::Bind;
  21 using base::Callback;
  22 using base::FileEnumerator;
  23 using base::FilePath;
  24 using base::Time;
  25 using base::TimeDelta;
  26 using base::TimeTicks;
  27 using content::BrowserThread;
  28 using std::map;
  29 using std::set;
  30 using std::string;
  31 using std::vector;
  32
  33 namespace {
  34
  35 typedef int32 Trigram;
  36 typedef char TrigramChar;
  37 typedef uint16 FileId;
  38
  39 const int kMinTimeoutBetweenWorkedNitification = 200;
  40 // Trigram characters include all ASCII printable characters (32-126) except for
  41 // the capital letters, because the index is case insensitive.
  42 const size_t kTrigramCharacterCount = 126 - 'Z' - 1 + 'A' - ' ' + 1;
  43 const size_t kTrigramCount =
  44     kTrigramCharacterCount * kTrigramCharacterCount * kTrigramCharacterCount;
  45 const int kMaxReadLength = 10 * 1024;
  46 const TrigramChar kUndefinedTrigramChar = -1;
  47 const Trigram kUndefinedTrigram = -1;
  48
  49 base::LazyInstance<vector<bool> >::Leaky g_is_binary_char =
  50     LAZY_INSTANCE_INITIALIZER;
  51
  52 base::LazyInstance<vector<TrigramChar> >::Leaky g_trigram_chars =
  53     LAZY_INSTANCE_INITIALIZER;
  54
  55 class Index {
  56  public:
  57   Index();
  58   Time LastModifiedTimeForFile(const FilePath& file_path);
  59   void SetTrigramsForFile(const FilePath& file_path,
  60                           const vector<Trigram>& index,
  61                           const Time& time);
  62   vector<FilePath> Search(string query);
  63   void PrintStats();
  64   void NormalizeVectors();
  65
  66  private:
  67   ~Index();
  68
  69   FileId GetFileId(const FilePath& file_path);
  70
  71   typedef map<FilePath, FileId> FileIdsMap;
  72   FileIdsMap file_ids_;
  73   FileId last_file_id_;
  74   // The index in this vector is the trigram id.
  75   vector<vector<FileId> > index_;
  76   typedef map<FilePath, Time> IndexedFilesMap;
  77   IndexedFilesMap index_times_;
  78   vector<bool> is_normalized_;
  79
  80   DISALLOW_COPY_AND_ASSIGN(Index);
  81 };
  82
  83 base::LazyInstance<Index>::Leaky g_trigram_index = LAZY_INSTANCE_INITIALIZER;
  84
  85 void InitIsBinaryCharMap() {
  86   for (size_t i = 0; i < 256; ++i) {
  87     unsigned char ch = i;
  88     bool is_binary_char = ch < 9 || (ch >= 14 && ch < 32) || ch == 127;
  89     g_is_binary_char.Get().push_back(is_binary_char);
  90   }
  91 }
  92
  93 bool IsBinaryChar(char c) {
  94   unsigned char uc = static_cast<unsigned char>(c);
  95   return g_is_binary_char.Get()[uc];
  96 }
  97
  98 void InitTrigramCharsMap() {
  99   for (size_t i = 0; i < 256; ++i) {
 100     if (i > 127) {
 101       g_trigram_chars.Get().push_back(kUndefinedTrigramChar);
 102       continue;
 103     }
 104     char ch = i;
 105     if (ch == '\t')
 106       ch = ' ';
 107     if (ch >= 'A' && ch <= 'Z')
 108       ch = ch - 'A' + 'a';
 109     if ((IsBinaryChar(ch)) || (ch < ' ')) {
 110       g_trigram_chars.Get().push_back(kUndefinedTrigramChar);
 111       continue;
 112     }
 113
 114     if (ch >= 'Z')
 115       ch = ch - 'Z' - 1 + 'A';
 116     ch -= ' ';
 117     char signed_trigram_char_count = static_cast<char>(kTrigramCharacterCount);
 118     CHECK(ch >= 0 && ch < signed_trigram_char_count);
 119     g_trigram_chars.Get().push_back(ch);
 120   }
 121 }
 122
 123 TrigramChar TrigramCharForChar(char c) {
 124   unsigned char uc = static_cast<unsigned char>(c);
 125   return g_trigram_chars.Get()[uc];
 126 }
 127
 128 Trigram TrigramAtIndex(const vector<TrigramChar>& trigram_chars, size_t index) {
 129   static int kTrigramCharacterCountSquared =
 130       kTrigramCharacterCount * kTrigramCharacterCount;
 131   if (trigram_chars[index] == kUndefinedTrigramChar ||
 132       trigram_chars[index + 1] == kUndefinedTrigramChar ||
 133       trigram_chars[index + 2] == kUndefinedTrigramChar)
 134     return kUndefinedTrigram;
 135   Trigram trigram = kTrigramCharacterCountSquared * trigram_chars[index] +
 136                     kTrigramCharacterCount * trigram_chars[index + 1] +
 137                     trigram_chars[index + 2];
 138   return trigram;
 139 }
 140
 141 Index::Index() : last_file_id_(0) {
 142   index_.resize(kTrigramCount);
 143   is_normalized_.resize(kTrigramCount);
 144   std::fill(is_normalized_.begin(), is_normalized_.end(), true);
 145 }
 146
 147 Index::~Index() {}
 148
 149 Time Index::LastModifiedTimeForFile(const FilePath& file_path) {
 150   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 151   Time last_modified_time;
 152   if (index_times_.find(file_path) != index_times_.end())
 153     last_modified_time = index_times_[file_path];
 154   return last_modified_time;
 155 }
 156
 157 void Index::SetTrigramsForFile(const FilePath& file_path,
 158                                const vector<Trigram>& index,
 159                                const Time& time) {
 160   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 161   FileId file_id = GetFileId(file_path);
 162   vector<Trigram>::const_iterator it = index.begin();
 163   for (; it != index.end(); ++it) {
 164     Trigram trigram = *it;
 165     index_[trigram].push_back(file_id);
 166     is_normalized_[trigram] = false;
 167   }
 168   index_times_[file_path] = time;
 169 }
 170
 171 vector<FilePath> Index::Search(string query) {
 172   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 173   const char* data = query.c_str();
 174   vector<TrigramChar> trigram_chars;
 175   trigram_chars.reserve(query.size());
 176   for (size_t i = 0; i < query.size(); ++i)
 177       trigram_chars.push_back(TrigramCharForChar(data[i]));
 178   vector<Trigram> trigrams;
 179   for (size_t i = 0; i + 2 < query.size(); ++i) {
 180     Trigram trigram = TrigramAtIndex(trigram_chars, i);
 181     if (trigram != kUndefinedTrigram)
 182       trigrams.push_back(trigram);
 183   }
 184   set<FileId> file_ids;
 185   bool first = true;
 186   vector<Trigram>::const_iterator it = trigrams.begin();
 187   for (; it != trigrams.end(); ++it) {
 188     Trigram trigram = *it;
 189     if (first) {
 190       std::copy(index_[trigram].begin(),
 191                 index_[trigram].end(),
 192                 std::inserter(file_ids, file_ids.begin()));
 193       first = false;
 194       continue;
 195     }
 196     set<FileId> intersection = base::STLSetIntersection<set<FileId> >(
 197         file_ids, index_[trigram]);
 198     file_ids.swap(intersection);
 199   }
 200   vector<FilePath> result;
 201   FileIdsMap::const_iterator ids_it = file_ids_.begin();
 202   for (; ids_it != file_ids_.end(); ++ids_it) {
 203     if (trigrams.size() == 0 ||
 204         file_ids.find(ids_it->second) != file_ids.end()) {
 205       result.push_back(ids_it->first);
 206     }
 207   }
 208   return result;
 209 }
 210
 211 FileId Index::GetFileId(const FilePath& file_path) {
 212   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 213   string file_path_str = file_path.AsUTF8Unsafe();
 214   if (file_ids_.find(file_path) != file_ids_.end())
 215     return file_ids_[file_path];
 216   file_ids_[file_path] = ++last_file_id_;
 217   return last_file_id_;
 218 }
 219
 220 void Index::NormalizeVectors() {
 221   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 222   for (size_t i = 0; i < kTrigramCount; ++i) {
 223     if (!is_normalized_[i]) {
 224       std::sort(index_[i].begin(), index_[i].end());
 225       if (index_[i].capacity() > index_[i].size())
 226         vector<FileId>(index_[i]).swap(index_[i]);
 227       is_normalized_[i] = true;
 228     }
 229   }
 230 }
 231
 232 void Index::PrintStats() {
 233   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 234   LOG(ERROR) << "Index stats:";
 235   size_t size = 0;
 236   size_t maxSize = 0;
 237   size_t capacity = 0;
 238   for (size_t i = 0; i < kTrigramCount; ++i) {
 239     if (index_[i].size() > maxSize)
 240       maxSize = index_[i].size();
 241     size += index_[i].size();
 242     capacity += index_[i].capacity();
 243   }
 244   LOG(ERROR) << "  - total trigram count: " << size;
 245   LOG(ERROR) << "  - max file count per trigram: " << maxSize;
 246   LOG(ERROR) << "  - total vectors capacity " << capacity;
 247   size_t total_index_size =
 248       capacity * sizeof(FileId) + sizeof(vector<FileId>) * kTrigramCount;
 249   LOG(ERROR) << "  - estimated total index size " << total_index_size;
 250 }
 251
 252 typedef Callback<void(bool, const vector<bool>&)> IndexerCallback;
 253
 254 }  // namespace
 255
 256 DevToolsFileSystemIndexer::FileSystemIndexingJob::FileSystemIndexingJob(
 257     const FilePath& file_system_path,
 258     const TotalWorkCallback& total_work_callback,
 259     const WorkedCallback& worked_callback,
 260     const DoneCallback& done_callback)
 261     : file_system_path_(file_system_path),
 262       total_work_callback_(total_work_callback),
 263       worked_callback_(worked_callback),
 264       done_callback_(done_callback),
 265       current_file_(BrowserThread::GetMessageLoopProxyForThread(
 266                         BrowserThread::FILE).get()),
 267       files_indexed_(0),
 268       stopped_(false) {
 269   current_trigrams_set_.resize(kTrigramCount);
 270   current_trigrams_.reserve(kTrigramCount);
 271 }
 272
 273 DevToolsFileSystemIndexer::FileSystemIndexingJob::~FileSystemIndexingJob() {}
 274
 275 void DevToolsFileSystemIndexer::FileSystemIndexingJob::Start() {
 276   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 277   BrowserThread::PostTask(
 278       BrowserThread::FILE,
 279       FROM_HERE,
 280       Bind(&FileSystemIndexingJob::CollectFilesToIndex, this));
 281 }
 282
 283 void DevToolsFileSystemIndexer::FileSystemIndexingJob::Stop() {
 284   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 285   BrowserThread::PostTask(BrowserThread::FILE,
 286                           FROM_HERE,
 287                           Bind(&FileSystemIndexingJob::StopOnFileThread, this));
 288 }
 289
 290 void DevToolsFileSystemIndexer::FileSystemIndexingJob::StopOnFileThread() {
 291   stopped_ = true;
 292 }
 293
 294 void DevToolsFileSystemIndexer::FileSystemIndexingJob::CollectFilesToIndex() {
 295   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 296   if (stopped_)
 297     return;
 298   if (!file_enumerator_) {
 299     file_enumerator_.reset(
 300         new FileEnumerator(file_system_path_, true, FileEnumerator::FILES));
 301   }
 302   FilePath file_path = file_enumerator_->Next();
 303   if (file_path.empty()) {
 304     BrowserThread::PostTask(
 305         BrowserThread::UI,
 306         FROM_HERE,
 307         Bind(total_work_callback_, file_path_times_.size()));
 308     indexing_it_ = file_path_times_.begin();
 309     IndexFiles();
 310     return;
 311   }
 312   Time saved_last_modified_time =
 313       g_trigram_index.Get().LastModifiedTimeForFile(file_path);
 314   FileEnumerator::FileInfo file_info = file_enumerator_->GetInfo();
 315   Time current_last_modified_time = file_info.GetLastModifiedTime();
 316   if (current_last_modified_time > saved_last_modified_time) {
 317     file_path_times_[file_path] = current_last_modified_time;
 318   }
 319   BrowserThread::PostTask(
 320       BrowserThread::FILE,
 321       FROM_HERE,
 322       Bind(&FileSystemIndexingJob::CollectFilesToIndex, this));
 323 }
 324
 325 void DevToolsFileSystemIndexer::FileSystemIndexingJob::IndexFiles() {
 326   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 327   if (stopped_)
 328     return;
 329   if (indexing_it_ == file_path_times_.end()) {
 330     g_trigram_index.Get().NormalizeVectors();
 331     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, done_callback_);
 332     return;
 333   }
 334   FilePath file_path = indexing_it_->first;
 335   current_file_.CreateOrOpen(
 336         file_path,
 337         base::File::FLAG_OPEN | base::File::FLAG_READ,
 338         Bind(&FileSystemIndexingJob::StartFileIndexing, this));
 339 }
 340
 341 void DevToolsFileSystemIndexer::FileSystemIndexingJob::StartFileIndexing(
 342     base::File::Error error) {
 343   if (!current_file_.IsValid()) {
 344     FinishFileIndexing(false);
 345     return;
 346   }
 347   current_file_offset_ = 0;
 348   current_trigrams_.clear();
 349   std::fill(current_trigrams_set_.begin(), current_trigrams_set_.end(), false);
 350   ReadFromFile();
 351 }
 352
 353 void DevToolsFileSystemIndexer::FileSystemIndexingJob::ReadFromFile() {
 354   if (stopped_) {
 355     CloseFile();
 356     return;
 357   }
 358   current_file_.Read(current_file_offset_, kMaxReadLength,
 359                      Bind(&FileSystemIndexingJob::OnRead, this));
 360 }
 361
 362 void DevToolsFileSystemIndexer::FileSystemIndexingJob::OnRead(
 363     base::File::Error error,
 364     const char* data,
 365     int bytes_read) {
 366   if (error != base::File::FILE_OK) {
 367     FinishFileIndexing(false);
 368     return;
 369   }
 370
 371   if (!bytes_read || bytes_read < 3) {
 372     FinishFileIndexing(true);
 373     return;
 374   }
 375
 376   size_t size = static_cast<size_t>(bytes_read);
 377   vector<TrigramChar> trigram_chars;
 378   trigram_chars.reserve(size);
 379   for (size_t i = 0; i < size; ++i) {
 380     if (IsBinaryChar(data[i])) {
 381       current_trigrams_.clear();
 382       FinishFileIndexing(true);
 383       return;
 384     }
 385     trigram_chars.push_back(TrigramCharForChar(data[i]));
 386   }
 387
 388   for (size_t i = 0; i + 2 < size; ++i) {
 389     Trigram trigram = TrigramAtIndex(trigram_chars, i);
 390     if ((trigram != kUndefinedTrigram) && !current_trigrams_set_[trigram]) {
 391       current_trigrams_set_[trigram] = true;
 392       current_trigrams_.push_back(trigram);
 393     }
 394   }
 395   current_file_offset_ += bytes_read - 2;
 396   ReadFromFile();
 397 }
 398
 399 void DevToolsFileSystemIndexer::FileSystemIndexingJob::FinishFileIndexing(
 400     bool success) {
 401   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 402   CloseFile();
 403   if (success) {
 404     FilePath file_path = indexing_it_->first;
 405     g_trigram_index.Get().SetTrigramsForFile(
 406         file_path, current_trigrams_, file_path_times_[file_path]);
 407   }
 408   ReportWorked();
 409   ++indexing_it_;
 410   IndexFiles();
 411 }
 412
 413 void DevToolsFileSystemIndexer::FileSystemIndexingJob::CloseFile() {
 414   if (current_file_.IsValid())
 415     current_file_.Close(Bind(&FileSystemIndexingJob::CloseCallback, this));
 416 }
 417
 418 void DevToolsFileSystemIndexer::FileSystemIndexingJob::CloseCallback(
 419     base::File::Error error) {}
 420
 421 void DevToolsFileSystemIndexer::FileSystemIndexingJob::ReportWorked() {
 422   TimeTicks current_time = TimeTicks::Now();
 423   bool should_send_worked_nitification = true;
 424   if (!last_worked_notification_time_.is_null()) {
 425     TimeDelta delta = current_time - last_worked_notification_time_;
 426     if (delta.InMilliseconds() < kMinTimeoutBetweenWorkedNitification)
 427       should_send_worked_nitification = false;
 428   }
 429   ++files_indexed_;
 430   if (should_send_worked_nitification) {
 431     last_worked_notification_time_ = current_time;
 432     BrowserThread::PostTask(
 433         BrowserThread::UI, FROM_HERE, Bind(worked_callback_, files_indexed_));
 434     files_indexed_ = 0;
 435   }
 436 }
 437
 438 DevToolsFileSystemIndexer::DevToolsFileSystemIndexer() {
 439   static bool maps_initialized = false;
 440   if (!maps_initialized) {
 441     InitIsBinaryCharMap();
 442     InitTrigramCharsMap();
 443     maps_initialized = true;
 444   }
 445 }
 446
 447 DevToolsFileSystemIndexer::~DevToolsFileSystemIndexer() {}
 448
 449 scoped_refptr<DevToolsFileSystemIndexer::FileSystemIndexingJob>
 450 DevToolsFileSystemIndexer::IndexPath(
 451     const string& file_system_path,
 452     const TotalWorkCallback& total_work_callback,
 453     const WorkedCallback& worked_callback,
 454     const DoneCallback& done_callback) {
 455   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 456   scoped_refptr<FileSystemIndexingJob> indexing_job =
 457       new FileSystemIndexingJob(FilePath::FromUTF8Unsafe(file_system_path),
 458                                 total_work_callback,
 459                                 worked_callback,
 460                                 done_callback);
 461   indexing_job->Start();
 462   return indexing_job;
 463 }
 464
 465 void DevToolsFileSystemIndexer::SearchInPath(const string& file_system_path,
 466                                              const string& query,
 467                                              const SearchCallback& callback) {
 468   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 469   BrowserThread::PostTask(
 470       BrowserThread::FILE,
 471       FROM_HERE,
 472       Bind(&DevToolsFileSystemIndexer::SearchInPathOnFileThread,
 473            this,
 474            file_system_path,
 475            query,
 476            callback));
 477 }
 478
 479 void DevToolsFileSystemIndexer::SearchInPathOnFileThread(
 480     const string& file_system_path,
 481     const string& query,
 482     const SearchCallback& callback) {
 483   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 484   vector<FilePath> file_paths = g_trigram_index.Get().Search(query);
 485   vector<string> result;
 486   FilePath path = FilePath::FromUTF8Unsafe(file_system_path);
 487   vector<FilePath>::const_iterator it = file_paths.begin();
 488   for (; it != file_paths.end(); ++it) {
 489     if (path.IsParent(*it))
 490       result.push_back(it->AsUTF8Unsafe());
 491   }
 492   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, Bind(callback, result));
 493 }