base/logging.cc

   1 // Copyright (c) 2012 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 "base/logging.h"
   6
   7 #if defined(OS_WIN)
   8 #include <io.h>
   9 #include <windows.h>
  10 typedef HANDLE FileHandle;
  11 typedef HANDLE MutexHandle;
  12 // Windows warns on using write().  It prefers _write().
  13 #define write(fd, buf, count) _write(fd, buf, static_cast<unsigned int>(count))
  14 // Windows doesn't define STDERR_FILENO.  Define it here.
  15 #define STDERR_FILENO 2
  16 #elif defined(OS_MACOSX)
  17 #include <mach/mach.h>
  18 #include <mach/mach_time.h>
  19 #include <mach-o/dyld.h>
  20 #elif defined(OS_POSIX)
  21 #if defined(OS_NACL)
  22 #include <sys/time.h> // timespec doesn't seem to be in <time.h>
  23 #else
  24 #include <sys/syscall.h>
  25 #endif
  26 #include <time.h>
  27 #endif
  28
  29 #if defined(OS_POSIX)
  30 #include <errno.h>
  31 #include <pthread.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <unistd.h>
  36 #define MAX_PATH PATH_MAX
  37 typedef FILE* FileHandle;
  38 typedef pthread_mutex_t* MutexHandle;
  39 #endif
  40
  41 #include <algorithm>
  42 #include <cstring>
  43 #include <ctime>
  44 #include <iomanip>
  45 #include <ostream>
  46
  47 #include "base/base_switches.h"
  48 #include "base/command_line.h"
  49 #include "base/debug/alias.h"
  50 #include "base/debug/debugger.h"
  51 #include "base/debug/stack_trace.h"
  52 #include "base/posix/eintr_wrapper.h"
  53 #include "base/strings/string_piece.h"
  54 #include "base/synchronization/lock_impl.h"
  55 #include "base/threading/platform_thread.h"
  56 #include "base/utf_string_conversions.h"
  57 #include "base/vlog.h"
  58 #if defined(OS_POSIX)
  59 #include "base/safe_strerror_posix.h"
  60 #endif
  61
  62 #if defined(OS_ANDROID)
  63 #include <android/log.h>
  64 #endif
  65
  66 namespace logging {
  67
  68 DcheckState g_dcheck_state = DISABLE_DCHECK_FOR_NON_OFFICIAL_RELEASE_BUILDS;
  69
  70 DcheckState get_dcheck_state() {
  71   return g_dcheck_state;
  72 }
  73
  74 void set_dcheck_state(DcheckState state) {
  75   g_dcheck_state = state;
  76 }
  77
  78 namespace {
  79
  80 VlogInfo* g_vlog_info = NULL;
  81 VlogInfo* g_vlog_info_prev = NULL;
  82
  83 const char* const log_severity_names[LOG_NUM_SEVERITIES] = {
  84   "INFO", "WARNING", "ERROR", "ERROR_REPORT", "FATAL" };
  85
  86 int min_log_level = 0;
  87
  88 // The default set here for logging_destination will only be used if
  89 // InitLogging is not called.  On Windows, use a file next to the exe;
  90 // on POSIX platforms, where it may not even be possible to locate the
  91 // executable on disk, use stderr.
  92 #if defined(OS_WIN)
  93 LoggingDestination logging_destination = LOG_ONLY_TO_FILE;
  94 #elif defined(OS_POSIX)
  95 LoggingDestination logging_destination = LOG_ONLY_TO_SYSTEM_DEBUG_LOG;
  96 #endif
  97
  98 // For LOG_ERROR and above, always print to stderr.
  99 const int kAlwaysPrintErrorLevel = LOG_ERROR;
 100
 101 // Which log file to use? This is initialized by InitLogging or
 102 // will be lazily initialized to the default value when it is
 103 // first needed.
 104 #if defined(OS_WIN)
 105 typedef std::wstring PathString;
 106 #else
 107 typedef std::string PathString;
 108 #endif
 109 PathString* log_file_name = NULL;
 110
 111 // this file is lazily opened and the handle may be NULL
 112 FileHandle log_file = NULL;
 113
 114 // what should be prepended to each message?
 115 bool log_process_id = false;
 116 bool log_thread_id = false;
 117 bool log_timestamp = true;
 118 bool log_tickcount = false;
 119
 120 // Should we pop up fatal debug messages in a dialog?
 121 bool show_error_dialogs = false;
 122
 123 // An assert handler override specified by the client to be called instead of
 124 // the debug message dialog and process termination.
 125 LogAssertHandlerFunction log_assert_handler = NULL;
 126 // An report handler override specified by the client to be called instead of
 127 // the debug message dialog.
 128 LogReportHandlerFunction log_report_handler = NULL;
 129 // A log message handler that gets notified of every log message we process.
 130 LogMessageHandlerFunction log_message_handler = NULL;
 131
 132 // Helper functions to wrap platform differences.
 133
 134 int32 CurrentProcessId() {
 135 #if defined(OS_WIN)
 136   return GetCurrentProcessId();
 137 #elif defined(OS_POSIX)
 138   return getpid();
 139 #endif
 140 }
 141
 142 uint64 TickCount() {
 143 #if defined(OS_WIN)
 144   return GetTickCount();
 145 #elif defined(OS_MACOSX)
 146   return mach_absolute_time();
 147 #elif defined(OS_NACL)
 148   // NaCl sadly does not have _POSIX_TIMERS enabled in sys/features.h
 149   // So we have to use clock() for now.
 150   return clock();
 151 #elif defined(OS_POSIX)
 152   struct timespec ts;
 153   clock_gettime(CLOCK_MONOTONIC, &ts);
 154
 155   uint64 absolute_micro =
 156     static_cast<int64>(ts.tv_sec) * 1000000 +
 157     static_cast<int64>(ts.tv_nsec) / 1000;
 158
 159   return absolute_micro;
 160 #endif
 161 }
 162
 163 void CloseFile(FileHandle log) {
 164 #if defined(OS_WIN)
 165   CloseHandle(log);
 166 #else
 167   fclose(log);
 168 #endif
 169 }
 170
 171 void DeleteFilePath(const PathString& log_name) {
 172 #if defined(OS_WIN)
 173   DeleteFile(log_name.c_str());
 174 #elif defined (OS_NACL)
 175   // Do nothing; unlink() isn't supported on NaCl.
 176 #else
 177   unlink(log_name.c_str());
 178 #endif
 179 }
 180
 181 PathString GetDefaultLogFile() {
 182 #if defined(OS_WIN)
 183   // On Windows we use the same path as the exe.
 184   wchar_t module_name[MAX_PATH];
 185   GetModuleFileName(NULL, module_name, MAX_PATH);
 186
 187   PathString log_file = module_name;
 188   PathString::size_type last_backslash =
 189       log_file.rfind('\\', log_file.size());
 190   if (last_backslash != PathString::npos)
 191     log_file.erase(last_backslash + 1);
 192   log_file += L"debug.log";
 193   return log_file;
 194 #elif defined(OS_POSIX)
 195   // On other platforms we just use the current directory.
 196   return PathString("debug.log");
 197 #endif
 198 }
 199
 200 // This class acts as a wrapper for locking the logging files.
 201 // LoggingLock::Init() should be called from the main thread before any logging
 202 // is done. Then whenever logging, be sure to have a local LoggingLock
 203 // instance on the stack. This will ensure that the lock is unlocked upon
 204 // exiting the frame.
 205 // LoggingLocks can not be nested.
 206 class LoggingLock {
 207  public:
 208   LoggingLock() {
 209     LockLogging();
 210   }
 211
 212   ~LoggingLock() {
 213     UnlockLogging();
 214   }
 215
 216   static void Init(LogLockingState lock_log, const PathChar* new_log_file) {
 217     if (initialized)
 218       return;
 219     lock_log_file = lock_log;
 220     if (lock_log_file == LOCK_LOG_FILE) {
 221 #if defined(OS_WIN)
 222       if (!log_mutex) {
 223         std::wstring safe_name;
 224         if (new_log_file)
 225           safe_name = new_log_file;
 226         else
 227           safe_name = GetDefaultLogFile();
 228         // \ is not a legal character in mutex names so we replace \ with /
 229         std::replace(safe_name.begin(), safe_name.end(), '\\', '/');
 230         std::wstring t(L"Global\\");
 231         t.append(safe_name);
 232         log_mutex = ::CreateMutex(NULL, FALSE, t.c_str());
 233
 234         if (log_mutex == NULL) {
 235 #if DEBUG
 236           // Keep the error code for debugging
 237           int error = GetLastError();  // NOLINT
 238           base::debug::BreakDebugger();
 239 #endif
 240           // Return nicely without putting initialized to true.
 241           return;
 242         }
 243       }
 244 #endif
 245     } else {
 246       log_lock = new base::internal::LockImpl();
 247     }
 248     initialized = true;
 249   }
 250
 251  private:
 252   static void LockLogging() {
 253     if (lock_log_file == LOCK_LOG_FILE) {
 254 #if defined(OS_WIN)
 255       ::WaitForSingleObject(log_mutex, INFINITE);
 256       // WaitForSingleObject could have returned WAIT_ABANDONED. We don't
 257       // abort the process here. UI tests might be crashy sometimes,
 258       // and aborting the test binary only makes the problem worse.
 259       // We also don't use LOG macros because that might lead to an infinite
 260       // loop. For more info see http://crbug.com/18028.
 261 #elif defined(OS_POSIX)
 262       pthread_mutex_lock(&log_mutex);
 263 #endif
 264     } else {
 265       // use the lock
 266       log_lock->Lock();
 267     }
 268   }
 269
 270   static void UnlockLogging() {
 271     if (lock_log_file == LOCK_LOG_FILE) {
 272 #if defined(OS_WIN)
 273       ReleaseMutex(log_mutex);
 274 #elif defined(OS_POSIX)
 275       pthread_mutex_unlock(&log_mutex);
 276 #endif
 277     } else {
 278       log_lock->Unlock();
 279     }
 280   }
 281
 282   // The lock is used if log file locking is false. It helps us avoid problems
 283   // with multiple threads writing to the log file at the same time.  Use
 284   // LockImpl directly instead of using Lock, because Lock makes logging calls.
 285   static base::internal::LockImpl* log_lock;
 286
 287   // When we don't use a lock, we are using a global mutex. We need to do this
 288   // because LockFileEx is not thread safe.
 289 #if defined(OS_WIN)
 290   static MutexHandle log_mutex;
 291 #elif defined(OS_POSIX)
 292   static pthread_mutex_t log_mutex;
 293 #endif
 294
 295   static bool initialized;
 296   static LogLockingState lock_log_file;
 297 };
 298
 299 // static
 300 bool LoggingLock::initialized = false;
 301 // static
 302 base::internal::LockImpl* LoggingLock::log_lock = NULL;
 303 // static
 304 LogLockingState LoggingLock::lock_log_file = LOCK_LOG_FILE;
 305
 306 #if defined(OS_WIN)
 307 // static
 308 MutexHandle LoggingLock::log_mutex = NULL;
 309 #elif defined(OS_POSIX)
 310 pthread_mutex_t LoggingLock::log_mutex = PTHREAD_MUTEX_INITIALIZER;
 311 #endif
 312
 313 // Called by logging functions to ensure that debug_file is initialized
 314 // and can be used for writing. Returns false if the file could not be
 315 // initialized. debug_file will be NULL in this case.
 316 bool InitializeLogFileHandle() {
 317   if (log_file)
 318     return true;
 319
 320   if (!log_file_name) {
 321     // Nobody has called InitLogging to specify a debug log file, so here we
 322     // initialize the log file name to a default.
 323     log_file_name = new PathString(GetDefaultLogFile());
 324   }
 325
 326   if (logging_destination == LOG_ONLY_TO_FILE ||
 327       logging_destination == LOG_TO_BOTH_FILE_AND_SYSTEM_DEBUG_LOG) {
 328 #if defined(OS_WIN)
 329     log_file = CreateFile(log_file_name->c_str(), GENERIC_WRITE,
 330                           FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
 331                           OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 332     if (log_file == INVALID_HANDLE_VALUE || log_file == NULL) {
 333       // try the current directory
 334       log_file = CreateFile(L".\\debug.log", GENERIC_WRITE,
 335                             FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
 336                             OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 337       if (log_file == INVALID_HANDLE_VALUE || log_file == NULL) {
 338         log_file = NULL;
 339         return false;
 340       }
 341     }
 342     SetFilePointer(log_file, 0, 0, FILE_END);
 343 #elif defined(OS_POSIX)
 344     log_file = fopen(log_file_name->c_str(), "a");
 345     if (log_file == NULL)
 346       return false;
 347 #endif
 348   }
 349
 350   return true;
 351 }
 352
 353 }  // namespace
 354
 355
 356 bool BaseInitLoggingImpl(const PathChar* new_log_file,
 357                          LoggingDestination logging_dest,
 358                          LogLockingState lock_log,
 359                          OldFileDeletionState delete_old,
 360                          DcheckState dcheck_state) {
 361 #if defined(OS_NACL)
 362   CHECK(logging_dest == LOG_NONE ||
 363         logging_dest == LOG_ONLY_TO_SYSTEM_DEBUG_LOG);
 364 #endif
 365   g_dcheck_state = dcheck_state;
 366   CommandLine* command_line = CommandLine::ForCurrentProcess();
 367   // Don't bother initializing g_vlog_info unless we use one of the
 368   // vlog switches.
 369   if (command_line->HasSwitch(switches::kV) ||
 370       command_line->HasSwitch(switches::kVModule)) {
 371     // NOTE: If g_vlog_info has already been initialized, it might be in use
 372     // by another thread. Don't delete the old VLogInfo, just create a second
 373     // one. We keep track of both to avoid memory leak warnings.
 374     CHECK(!g_vlog_info_prev);
 375     g_vlog_info_prev = g_vlog_info;
 376
 377     g_vlog_info =
 378         new VlogInfo(command_line->GetSwitchValueASCII(switches::kV),
 379                      command_line->GetSwitchValueASCII(switches::kVModule),
 380                      &min_log_level);
 381   }
 382
 383   LoggingLock::Init(lock_log, new_log_file);
 384
 385   LoggingLock logging_lock;
 386
 387   if (log_file) {
 388     // calling InitLogging twice or after some log call has already opened the
 389     // default log file will re-initialize to the new options
 390     CloseFile(log_file);
 391     log_file = NULL;
 392   }
 393
 394   logging_destination = logging_dest;
 395
 396   // ignore file options if logging is disabled or only to system
 397   if (logging_destination == LOG_NONE ||
 398       logging_destination == LOG_ONLY_TO_SYSTEM_DEBUG_LOG)
 399     return true;
 400
 401   if (!log_file_name)
 402     log_file_name = new PathString();
 403   *log_file_name = new_log_file;
 404   if (delete_old == DELETE_OLD_LOG_FILE)
 405     DeleteFilePath(*log_file_name);
 406
 407   return InitializeLogFileHandle();
 408 }
 409
 410 void SetMinLogLevel(int level) {
 411   min_log_level = std::min(LOG_ERROR_REPORT, level);
 412 }
 413
 414 int GetMinLogLevel() {
 415   return min_log_level;
 416 }
 417
 418 int GetVlogVerbosity() {
 419   return std::max(-1, LOG_INFO - GetMinLogLevel());
 420 }
 421
 422 int GetVlogLevelHelper(const char* file, size_t N) {
 423   DCHECK_GT(N, 0U);
 424   // Note: g_vlog_info may change on a different thread during startup
 425   // (but will always be valid or NULL).
 426   VlogInfo* vlog_info = g_vlog_info;
 427   return vlog_info ?
 428       vlog_info->GetVlogLevel(base::StringPiece(file, N - 1)) :
 429       GetVlogVerbosity();
 430 }
 431
 432 void SetLogItems(bool enable_process_id, bool enable_thread_id,
 433                  bool enable_timestamp, bool enable_tickcount) {
 434   log_process_id = enable_process_id;
 435   log_thread_id = enable_thread_id;
 436   log_timestamp = enable_timestamp;
 437   log_tickcount = enable_tickcount;
 438 }
 439
 440 void SetShowErrorDialogs(bool enable_dialogs) {
 441   show_error_dialogs = enable_dialogs;
 442 }
 443
 444 void SetLogAssertHandler(LogAssertHandlerFunction handler) {
 445   log_assert_handler = handler;
 446 }
 447
 448 void SetLogReportHandler(LogReportHandlerFunction handler) {
 449   log_report_handler = handler;
 450 }
 451
 452 void SetLogMessageHandler(LogMessageHandlerFunction handler) {
 453   log_message_handler = handler;
 454 }
 455
 456 LogMessageHandlerFunction GetLogMessageHandler() {
 457   return log_message_handler;
 458 }
 459
 460 // MSVC doesn't like complex extern templates and DLLs.
 461 #if !defined(COMPILER_MSVC)
 462 // Explicit instantiations for commonly used comparisons.
 463 template std::string* MakeCheckOpString<int, int>(
 464     const int&, const int&, const char* names);
 465 template std::string* MakeCheckOpString<unsigned long, unsigned long>(
 466     const unsigned long&, const unsigned long&, const char* names);
 467 template std::string* MakeCheckOpString<unsigned long, unsigned int>(
 468     const unsigned long&, const unsigned int&, const char* names);
 469 template std::string* MakeCheckOpString<unsigned int, unsigned long>(
 470     const unsigned int&, const unsigned long&, const char* names);
 471 template std::string* MakeCheckOpString<std::string, std::string>(
 472     const std::string&, const std::string&, const char* name);
 473 #endif
 474
 475 // Displays a message box to the user with the error message in it.
 476 // Used for fatal messages, where we close the app simultaneously.
 477 // This is for developers only; we don't use this in circumstances
 478 // (like release builds) where users could see it, since users don't
 479 // understand these messages anyway.
 480 void DisplayDebugMessageInDialog(const std::string& str) {
 481   if (str.empty())
 482     return;
 483
 484   if (!show_error_dialogs)
 485     return;
 486
 487 #if defined(OS_WIN)
 488   // For Windows programs, it's possible that the message loop is
 489   // messed up on a fatal error, and creating a MessageBox will cause
 490   // that message loop to be run. Instead, we try to spawn another
 491   // process that displays its command line. We look for "Debug
 492   // Message.exe" in the same directory as the application. If it
 493   // exists, we use it, otherwise, we use a regular message box.
 494   wchar_t prog_name[MAX_PATH];
 495   GetModuleFileNameW(NULL, prog_name, MAX_PATH);
 496   wchar_t* backslash = wcsrchr(prog_name, '\\');
 497   if (backslash)
 498     backslash[1] = 0;
 499   wcscat_s(prog_name, MAX_PATH, L"debug_message.exe");
 500
 501   std::wstring cmdline = UTF8ToWide(str);
 502   if (cmdline.empty())
 503     return;
 504
 505   STARTUPINFO startup_info;
 506   memset(&startup_info, 0, sizeof(startup_info));
 507   startup_info.cb = sizeof(startup_info);
 508
 509   PROCESS_INFORMATION process_info;
 510   if (CreateProcessW(prog_name, &cmdline[0], NULL, NULL, false, 0, NULL,
 511                      NULL, &startup_info, &process_info)) {
 512     WaitForSingleObject(process_info.hProcess, INFINITE);
 513     CloseHandle(process_info.hThread);
 514     CloseHandle(process_info.hProcess);
 515   } else {
 516     // debug process broken, let's just do a message box
 517     MessageBoxW(NULL, &cmdline[0], L"Fatal error",
 518                 MB_OK | MB_ICONHAND | MB_TOPMOST);
 519   }
 520 #else
 521   // We intentionally don't implement a dialog on other platforms.
 522   // You can just look at stderr.
 523 #endif
 524 }
 525
 526 #if defined(OS_WIN)
 527 LogMessage::SaveLastError::SaveLastError() : last_error_(::GetLastError()) {
 528 }
 529
 530 LogMessage::SaveLastError::~SaveLastError() {
 531   ::SetLastError(last_error_);
 532 }
 533 #endif  // defined(OS_WIN)
 534
 535 LogMessage::LogMessage(const char* file, int line, LogSeverity severity,
 536                        int ctr)
 537     : severity_(severity), file_(file), line_(line) {
 538   Init(file, line);
 539 }
 540
 541 LogMessage::LogMessage(const char* file, int line)
 542     : severity_(LOG_INFO), file_(file), line_(line) {
 543   Init(file, line);
 544 }
 545
 546 LogMessage::LogMessage(const char* file, int line, LogSeverity severity)
 547     : severity_(severity), file_(file), line_(line) {
 548   Init(file, line);
 549 }
 550
 551 LogMessage::LogMessage(const char* file, int line, std::string* result)
 552     : severity_(LOG_FATAL), file_(file), line_(line) {
 553   Init(file, line);
 554   stream_ << "Check failed: " << *result;
 555   delete result;
 556 }
 557
 558 LogMessage::LogMessage(const char* file, int line, LogSeverity severity,
 559                        std::string* result)
 560     : severity_(severity), file_(file), line_(line) {
 561   Init(file, line);
 562   stream_ << "Check failed: " << *result;
 563   delete result;
 564 }
 565
 566 LogMessage::~LogMessage() {
 567   // TODO(port): enable stacktrace generation on LOG_FATAL once backtrace are
 568   // working in Android.
 569 #if  !defined(NDEBUG) && !defined(OS_ANDROID) && !defined(OS_NACL)
 570   if (severity_ == LOG_FATAL) {
 571     // Include a stack trace on a fatal.
 572     base::debug::StackTrace trace;
 573     stream_ << std::endl;  // Newline to separate from log message.
 574     trace.OutputToStream(&stream_);
 575   }
 576 #endif
 577   stream_ << std::endl;
 578   std::string str_newline(stream_.str());
 579
 580   // Give any log message handler first dibs on the message.
 581   if (log_message_handler && log_message_handler(severity_, file_, line_,
 582           message_start_, str_newline)) {
 583     // The handler took care of it, no further processing.
 584     return;
 585   }
 586
 587   if (logging_destination == LOG_ONLY_TO_SYSTEM_DEBUG_LOG ||
 588       logging_destination == LOG_TO_BOTH_FILE_AND_SYSTEM_DEBUG_LOG) {
 589 #if defined(OS_WIN)
 590     OutputDebugStringA(str_newline.c_str());
 591 #elif defined(OS_ANDROID)
 592     android_LogPriority priority =
 593         (severity_ < 0) ? ANDROID_LOG_VERBOSE : ANDROID_LOG_UNKNOWN;
 594     switch (severity_) {
 595       case LOG_INFO:
 596         priority = ANDROID_LOG_INFO;
 597         break;
 598       case LOG_WARNING:
 599         priority = ANDROID_LOG_WARN;
 600         break;
 601       case LOG_ERROR:
 602       case LOG_ERROR_REPORT:
 603         priority = ANDROID_LOG_ERROR;
 604         break;
 605       case LOG_FATAL:
 606         priority = ANDROID_LOG_FATAL;
 607         break;
 608     }
 609     __android_log_write(priority, "chromium", str_newline.c_str());
 610 #endif
 611     fprintf(stderr, "%s", str_newline.c_str());
 612     fflush(stderr);
 613   } else if (severity_ >= kAlwaysPrintErrorLevel) {
 614     // When we're only outputting to a log file, above a certain log level, we
 615     // should still output to stderr so that we can better detect and diagnose
 616     // problems with unit tests, especially on the buildbots.
 617     fprintf(stderr, "%s", str_newline.c_str());
 618     fflush(stderr);
 619   }
 620
 621   // We can have multiple threads and/or processes, so try to prevent them
 622   // from clobbering each other's writes.
 623   // If the client app did not call InitLogging, and the lock has not
 624   // been created do it now. We do this on demand, but if two threads try
 625   // to do this at the same time, there will be a race condition to create
 626   // the lock. This is why InitLogging should be called from the main
 627   // thread at the beginning of execution.
 628   LoggingLock::Init(LOCK_LOG_FILE, NULL);
 629   // write to log file
 630   if (logging_destination != LOG_NONE &&
 631       logging_destination != LOG_ONLY_TO_SYSTEM_DEBUG_LOG) {
 632     LoggingLock logging_lock;
 633     if (InitializeLogFileHandle()) {
 634 #if defined(OS_WIN)
 635       SetFilePointer(log_file, 0, 0, SEEK_END);
 636       DWORD num_written;
 637       WriteFile(log_file,
 638                 static_cast<const void*>(str_newline.c_str()),
 639                 static_cast<DWORD>(str_newline.length()),
 640                 &num_written,
 641                 NULL);
 642 #else
 643       fprintf(log_file, "%s", str_newline.c_str());
 644       fflush(log_file);
 645 #endif
 646     }
 647   }
 648
 649   if (severity_ == LOG_FATAL) {
 650     // Ensure the first characters of the string are on the stack so they
 651     // are contained in minidumps for diagnostic purposes.
 652     char str_stack[1024];
 653     str_newline.copy(str_stack, arraysize(str_stack));
 654     base::debug::Alias(str_stack);
 655
 656     // display a message or break into the debugger on a fatal error
 657     if (base::debug::BeingDebugged()) {
 658       base::debug::BreakDebugger();
 659     } else {
 660       if (log_assert_handler) {
 661         // make a copy of the string for the handler out of paranoia
 662         log_assert_handler(std::string(stream_.str()));
 663       } else {
 664         // Don't use the string with the newline, get a fresh version to send to
 665         // the debug message process. We also don't display assertions to the
 666         // user in release mode. The enduser can't do anything with this
 667         // information, and displaying message boxes when the application is
 668         // hosed can cause additional problems.
 669 #ifndef NDEBUG
 670         DisplayDebugMessageInDialog(stream_.str());
 671 #endif
 672         // Crash the process to generate a dump.
 673         base::debug::BreakDebugger();
 674       }
 675     }
 676   } else if (severity_ == LOG_ERROR_REPORT) {
 677     // We are here only if the user runs with --enable-dcheck in release mode.
 678     if (log_report_handler) {
 679       log_report_handler(std::string(stream_.str()));
 680     } else {
 681       DisplayDebugMessageInDialog(stream_.str());
 682     }
 683   }
 684 }
 685
 686 // writes the common header info to the stream
 687 void LogMessage::Init(const char* file, int line) {
 688   base::StringPiece filename(file);
 689   size_t last_slash_pos = filename.find_last_of("\\/");
 690   if (last_slash_pos != base::StringPiece::npos)
 691     filename.remove_prefix(last_slash_pos + 1);
 692
 693   // TODO(darin): It might be nice if the columns were fixed width.
 694
 695   stream_ <<  '[';
 696   if (log_process_id)
 697     stream_ << CurrentProcessId() << ':';
 698   if (log_thread_id)
 699     stream_ << base::PlatformThread::CurrentId() << ':';
 700   if (log_timestamp) {
 701     time_t t = time(NULL);
 702     struct tm local_time = {0};
 703 #if _MSC_VER >= 1400
 704     localtime_s(&local_time, &t);
 705 #else
 706     localtime_r(&t, &local_time);
 707 #endif
 708     struct tm* tm_time = &local_time;
 709     stream_ << std::setfill('0')
 710             << std::setw(2) << 1 + tm_time->tm_mon
 711             << std::setw(2) << tm_time->tm_mday
 712             << '/'
 713             << std::setw(2) << tm_time->tm_hour
 714             << std::setw(2) << tm_time->tm_min
 715             << std::setw(2) << tm_time->tm_sec
 716             << ':';
 717   }
 718   if (log_tickcount)
 719     stream_ << TickCount() << ':';
 720   if (severity_ >= 0)
 721     stream_ << log_severity_names[severity_];
 722   else
 723     stream_ << "VERBOSE" << -severity_;
 724
 725   stream_ << ":" << filename << "(" << line << ")] ";
 726
 727   message_start_ = stream_.tellp();
 728 }
 729
 730 #if defined(OS_WIN)
 731 // This has already been defined in the header, but defining it again as DWORD
 732 // ensures that the type used in the header is equivalent to DWORD. If not,
 733 // the redefinition is a compile error.
 734 typedef DWORD SystemErrorCode;
 735 #endif
 736
 737 SystemErrorCode GetLastSystemErrorCode() {
 738 #if defined(OS_WIN)
 739   return ::GetLastError();
 740 #elif defined(OS_POSIX)
 741   return errno;
 742 #else
 743 #error Not implemented
 744 #endif
 745 }
 746
 747 #if defined(OS_WIN)
 748 Win32ErrorLogMessage::Win32ErrorLogMessage(const char* file,
 749                                            int line,
 750                                            LogSeverity severity,
 751                                            SystemErrorCode err,
 752                                            const char* module)
 753     : err_(err),
 754       module_(module),
 755       log_message_(file, line, severity) {
 756 }
 757
 758 Win32ErrorLogMessage::Win32ErrorLogMessage(const char* file,
 759                                            int line,
 760                                            LogSeverity severity,
 761                                            SystemErrorCode err)
 762     : err_(err),
 763       module_(NULL),
 764       log_message_(file, line, severity) {
 765 }
 766
 767 Win32ErrorLogMessage::~Win32ErrorLogMessage() {
 768   const int error_message_buffer_size = 256;
 769   char msgbuf[error_message_buffer_size];
 770   DWORD flags = FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS;
 771   HMODULE hmod;
 772   if (module_) {
 773     hmod = GetModuleHandleA(module_);
 774     if (hmod) {
 775       flags |= FORMAT_MESSAGE_FROM_HMODULE;
 776     } else {
 777       // This makes a nested Win32ErrorLogMessage. It will have module_ of NULL
 778       // so it will not call GetModuleHandle, so recursive errors are
 779       // impossible.
 780       DPLOG(WARNING) << "Couldn't open module " << module_
 781           << " for error message query";
 782     }
 783   } else {
 784     hmod = NULL;
 785   }
 786   DWORD len = FormatMessageA(flags,
 787                              hmod,
 788                              err_,
 789                              0,
 790                              msgbuf,
 791                              sizeof(msgbuf) / sizeof(msgbuf[0]),
 792                              NULL);
 793   if (len) {
 794     while ((len > 0) &&
 795            isspace(static_cast<unsigned char>(msgbuf[len - 1]))) {
 796       msgbuf[--len] = 0;
 797     }
 798     stream() << ": " << msgbuf;
 799   } else {
 800     stream() << ": Error " << GetLastError() << " while retrieving error "
 801         << err_;
 802   }
 803   // We're about to crash (CHECK). Put |err_| on the stack (by placing it in a
 804   // field) and use Alias in hopes that it makes it into crash dumps.
 805   DWORD last_error = err_;
 806   base::debug::Alias(&last_error);
 807 }
 808 #elif defined(OS_POSIX)
 809 ErrnoLogMessage::ErrnoLogMessage(const char* file,
 810                                  int line,
 811                                  LogSeverity severity,
 812                                  SystemErrorCode err)
 813     : err_(err),
 814       log_message_(file, line, severity) {
 815 }
 816
 817 ErrnoLogMessage::~ErrnoLogMessage() {
 818   stream() << ": " << safe_strerror(err_);
 819 }
 820 #endif  // OS_WIN
 821
 822 void CloseLogFile() {
 823   LoggingLock logging_lock;
 824
 825   if (!log_file)
 826     return;
 827
 828   CloseFile(log_file);
 829   log_file = NULL;
 830 }
 831
 832 void RawLog(int level, const char* message) {
 833   if (level >= min_log_level) {
 834     size_t bytes_written = 0;
 835     const size_t message_len = strlen(message);
 836     int rv;
 837     while (bytes_written < message_len) {
 838       rv = HANDLE_EINTR(
 839           write(STDERR_FILENO, message + bytes_written,
 840                 message_len - bytes_written));
 841       if (rv < 0) {
 842         // Give up, nothing we can do now.
 843         break;
 844       }
 845       bytes_written += rv;
 846     }
 847
 848     if (message_len > 0 && message[message_len - 1] != '\n') {
 849       do {
 850         rv = HANDLE_EINTR(write(STDERR_FILENO, "\n", 1));
 851         if (rv < 0) {
 852           // Give up, nothing we can do now.
 853           break;
 854         }
 855       } while (rv != 1);
 856     }
 857   }
 858
 859   if (level == LOG_FATAL)
 860     base::debug::BreakDebugger();
 861 }
 862
 863 // This was defined at the beginning of this file.
 864 #undef write
 865
 866 #if defined(OS_WIN)
 867 std::wstring GetLogFileFullPath() {
 868   if (log_file_name)
 869     return *log_file_name;
 870   return std::wstring();
 871 }
 872 #endif
 873
 874 }  // namespace logging
 875
 876 std::ostream& operator<<(std::ostream& out, const wchar_t* wstr) {
 877   return out << WideToUTF8(std::wstring(wstr));
 878 }