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