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