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      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 // MSVC doesn't like complex extern templates and DLLs.
    448 #if !defined(COMPILER_MSVC)
    449 // Explicit instantiations for commonly used comparisons.
    450 template std::string* MakeCheckOpString<int, int>(
    451     const int&, const int&, const char* names);
    452 template std::string* MakeCheckOpString<unsigned long, unsigned long>(
    453     const unsigned long&, const unsigned long&, const char* names);
    454 template std::string* MakeCheckOpString<unsigned long, unsigned int>(
    455     const unsigned long&, const unsigned int&, const char* names);
    456 template std::string* MakeCheckOpString<unsigned int, unsigned long>(
    457     const unsigned int&, const unsigned long&, const char* names);
    458 template std::string* MakeCheckOpString<std::string, std::string>(
    459     const std::string&, const std::string&, const char* name);
    460 #endif
    461 
    462 #if !defined(NDEBUG)
    463 // Displays a message box to the user with the error message in it.
    464 // Used for fatal messages, where we close the app simultaneously.
    465 // This is for developers only; we don't use this in circumstances
    466 // (like release builds) where users could see it, since users don't
    467 // understand these messages anyway.
    468 void DisplayDebugMessageInDialog(const std::string& str) {
    469   if (str.empty())
    470     return;
    471 
    472   if (!show_error_dialogs)
    473     return;
    474 
    475 #if defined(OS_WIN)
    476   // For Windows programs, it's possible that the message loop is
    477   // messed up on a fatal error, and creating a MessageBox will cause
    478   // that message loop to be run. Instead, we try to spawn another
    479   // process that displays its command line. We look for "Debug
    480   // Message.exe" in the same directory as the application. If it
    481   // exists, we use it, otherwise, we use a regular message box.
    482   wchar_t prog_name[MAX_PATH];
    483   GetModuleFileNameW(NULL, prog_name, MAX_PATH);
    484   wchar_t* backslash = wcsrchr(prog_name, '\\');
    485   if (backslash)
    486     backslash[1] = 0;
    487   wcscat_s(prog_name, MAX_PATH, L"debug_message.exe");
    488 
    489   std::wstring cmdline = base::UTF8ToWide(str);
    490   if (cmdline.empty())
    491     return;
    492 
    493   STARTUPINFO startup_info;
    494   memset(&startup_info, 0, sizeof(startup_info));
    495   startup_info.cb = sizeof(startup_info);
    496 
    497   PROCESS_INFORMATION process_info;
    498   if (CreateProcessW(prog_name, &cmdline[0], NULL, NULL, false, 0, NULL,
    499                      NULL, &startup_info, &process_info)) {
    500     WaitForSingleObject(process_info.hProcess, INFINITE);
    501     CloseHandle(process_info.hThread);
    502     CloseHandle(process_info.hProcess);
    503   } else {
    504     // debug process broken, let's just do a message box
    505     MessageBoxW(NULL, &cmdline[0], L"Fatal error",
    506                 MB_OK | MB_ICONHAND | MB_TOPMOST);
    507   }
    508 #else
    509   // We intentionally don't implement a dialog on other platforms.
    510   // You can just look at stderr.
    511 #endif
    512 }
    513 #endif  // !defined(NDEBUG)
    514 
    515 #if defined(OS_WIN)
    516 LogMessage::SaveLastError::SaveLastError() : last_error_(::GetLastError()) {
    517 }
    518 
    519 LogMessage::SaveLastError::~SaveLastError() {
    520   ::SetLastError(last_error_);
    521 }
    522 #endif  // defined(OS_WIN)
    523 
    524 LogMessage::LogMessage(const char* file, int line, LogSeverity severity)
    525     : severity_(severity), file_(file), line_(line) {
    526   Init(file, line);
    527 }
    528 
    529 LogMessage::LogMessage(const char* file, int line, std::string* result)
    530     : severity_(LOG_FATAL), file_(file), line_(line) {
    531   Init(file, line);
    532   stream_ << "Check failed: " << *result;
    533   delete result;
    534 }
    535 
    536 LogMessage::LogMessage(const char* file, int line, LogSeverity severity,
    537                        std::string* result)
    538     : severity_(severity), file_(file), line_(line) {
    539   Init(file, line);
    540   stream_ << "Check failed: " << *result;
    541   delete result;
    542 }
    543 
    544 LogMessage::~LogMessage() {
    545 #if !defined(NDEBUG) && !defined(OS_NACL) && !defined(__UCLIBC__)
    546   if (severity_ == LOG_FATAL) {
    547     // Include a stack trace on a fatal.
    548     base::debug::StackTrace trace;
    549     stream_ << std::endl;  // Newline to separate from log message.
    550     trace.OutputToStream(&stream_);
    551   }
    552 #endif
    553   stream_ << std::endl;
    554   std::string str_newline(stream_.str());
    555 
    556   // Give any log message handler first dibs on the message.
    557   if (log_message_handler &&
    558       log_message_handler(severity_, file_, line_,
    559                           message_start_, str_newline)) {
    560     // The handler took care of it, no further processing.
    561     return;
    562   }
    563 
    564   if ((logging_destination & LOG_TO_SYSTEM_DEBUG_LOG) != 0) {
    565 #if defined(OS_WIN)
    566     OutputDebugStringA(str_newline.c_str());
    567 #elif defined(OS_ANDROID)
    568     android_LogPriority priority =
    569         (severity_ < 0) ? ANDROID_LOG_VERBOSE : ANDROID_LOG_UNKNOWN;
    570     switch (severity_) {
    571       case LOG_INFO:
    572         priority = ANDROID_LOG_INFO;
    573         break;
    574       case LOG_WARNING:
    575         priority = ANDROID_LOG_WARN;
    576         break;
    577       case LOG_ERROR:
    578         priority = ANDROID_LOG_ERROR;
    579         break;
    580       case LOG_FATAL:
    581         priority = ANDROID_LOG_FATAL;
    582         break;
    583     }
    584     __android_log_write(priority, "chromium", str_newline.c_str());
    585 #endif
    586     ignore_result(fwrite(str_newline.data(), str_newline.size(), 1, stderr));
    587     fflush(stderr);
    588   } else if (severity_ >= kAlwaysPrintErrorLevel) {
    589     // When we're only outputting to a log file, above a certain log level, we
    590     // should still output to stderr so that we can better detect and diagnose
    591     // problems with unit tests, especially on the buildbots.
    592     ignore_result(fwrite(str_newline.data(), str_newline.size(), 1, stderr));
    593     fflush(stderr);
    594   }
    595 
    596   // write to log file
    597   if ((logging_destination & LOG_TO_FILE) != 0) {
    598     // We can have multiple threads and/or processes, so try to prevent them
    599     // from clobbering each other's writes.
    600     // If the client app did not call InitLogging, and the lock has not
    601     // been created do it now. We do this on demand, but if two threads try
    602     // to do this at the same time, there will be a race condition to create
    603     // the lock. This is why InitLogging should be called from the main
    604     // thread at the beginning of execution.
    605     LoggingLock::Init(LOCK_LOG_FILE, NULL);
    606     LoggingLock logging_lock;
    607     if (InitializeLogFileHandle()) {
    608 #if defined(OS_WIN)
    609       SetFilePointer(log_file, 0, 0, SEEK_END);
    610       DWORD num_written;
    611       WriteFile(log_file,
    612                 static_cast<const void*>(str_newline.c_str()),
    613                 static_cast<DWORD>(str_newline.length()),
    614                 &num_written,
    615                 NULL);
    616 #else
    617       ignore_result(fwrite(
    618           str_newline.data(), str_newline.size(), 1, log_file));
    619       fflush(log_file);
    620 #endif
    621     }
    622   }
    623 
    624   if (severity_ == LOG_FATAL) {
    625     // Ensure the first characters of the string are on the stack so they
    626     // are contained in minidumps for diagnostic purposes.
    627     char str_stack[1024];
    628     str_newline.copy(str_stack, arraysize(str_stack));
    629     base::debug::Alias(str_stack);
    630 
    631     if (log_assert_handler) {
    632       // Make a copy of the string for the handler out of paranoia.
    633       log_assert_handler(std::string(stream_.str()));
    634     } else {
    635       // Don't use the string with the newline, get a fresh version to send to
    636       // the debug message process. We also don't display assertions to the
    637       // user in release mode. The enduser can't do anything with this
    638       // information, and displaying message boxes when the application is
    639       // hosed can cause additional problems.
    640 #ifndef NDEBUG
    641       DisplayDebugMessageInDialog(stream_.str());
    642 #endif
    643       // Crash the process to generate a dump.
    644       base::debug::BreakDebugger();
    645     }
    646   }
    647 }
    648 
    649 // writes the common header info to the stream
    650 void LogMessage::Init(const char* file, int line) {
    651   base::StringPiece filename(file);
    652   size_t last_slash_pos = filename.find_last_of("\\/");
    653   if (last_slash_pos != base::StringPiece::npos)
    654     filename.remove_prefix(last_slash_pos + 1);
    655 
    656   // TODO(darin): It might be nice if the columns were fixed width.
    657 
    658   stream_ <<  '[';
    659   if (log_process_id)
    660     stream_ << CurrentProcessId() << ':';
    661   if (log_thread_id)
    662     stream_ << base::PlatformThread::CurrentId() << ':';
    663   if (log_timestamp) {
    664     time_t t = time(NULL);
    665     struct tm local_time = {0};
    666 #if _MSC_VER >= 1400
    667     localtime_s(&local_time, &t);
    668 #else
    669     localtime_r(&t, &local_time);
    670 #endif
    671     struct tm* tm_time = &local_time;
    672     stream_ << std::setfill('0')
    673             << std::setw(2) << 1 + tm_time->tm_mon
    674             << std::setw(2) << tm_time->tm_mday
    675             << '/'
    676             << std::setw(2) << tm_time->tm_hour
    677             << std::setw(2) << tm_time->tm_min
    678             << std::setw(2) << tm_time->tm_sec
    679             << ':';
    680   }
    681   if (log_tickcount)
    682     stream_ << TickCount() << ':';
    683   if (severity_ >= 0)
    684     stream_ << log_severity_name(severity_);
    685   else
    686     stream_ << "VERBOSE" << -severity_;
    687 
    688   stream_ << ":" << filename << "(" << line << ")] ";
    689 
    690   message_start_ = stream_.tellp();
    691 }
    692 
    693 #if defined(OS_WIN)
    694 // This has already been defined in the header, but defining it again as DWORD
    695 // ensures that the type used in the header is equivalent to DWORD. If not,
    696 // the redefinition is a compile error.
    697 typedef DWORD SystemErrorCode;
    698 #endif
    699 
    700 SystemErrorCode GetLastSystemErrorCode() {
    701 #if defined(OS_WIN)
    702   return ::GetLastError();
    703 #elif defined(OS_POSIX)
    704   return errno;
    705 #else
    706 #error Not implemented
    707 #endif
    708 }
    709 
    710 #if defined(OS_WIN)
    711 BASE_EXPORT std::string SystemErrorCodeToString(SystemErrorCode error_code) {
    712   const int error_message_buffer_size = 256;
    713   char msgbuf[error_message_buffer_size];
    714   DWORD flags = FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS;
    715   DWORD len = FormatMessageA(flags, NULL, error_code, 0, msgbuf,
    716                              arraysize(msgbuf), NULL);
    717   if (len) {
    718     // Messages returned by system end with line breaks.
    719     return base::CollapseWhitespaceASCII(msgbuf, true) +
    720         base::StringPrintf(" (0x%X)", error_code);
    721   }
    722   return base::StringPrintf("Error (0x%X) while retrieving error. (0x%X)",
    723                             GetLastError(), error_code);
    724 }
    725 #elif defined(OS_POSIX)
    726 BASE_EXPORT std::string SystemErrorCodeToString(SystemErrorCode error_code) {
    727   return safe_strerror(error_code);
    728 }
    729 #else
    730 #error Not implemented
    731 #endif
    732 
    733 
    734 #if defined(OS_WIN)
    735 Win32ErrorLogMessage::Win32ErrorLogMessage(const char* file,
    736                                            int line,
    737                                            LogSeverity severity,
    738                                            SystemErrorCode err)
    739     : err_(err),
    740       log_message_(file, line, severity) {
    741 }
    742 
    743 Win32ErrorLogMessage::~Win32ErrorLogMessage() {
    744   stream() << ": " << SystemErrorCodeToString(err_);
    745   // We're about to crash (CHECK). Put |err_| on the stack (by placing it in a
    746   // field) and use Alias in hopes that it makes it into crash dumps.
    747   DWORD last_error = err_;
    748   base::debug::Alias(&last_error);
    749 }
    750 #elif defined(OS_POSIX)
    751 ErrnoLogMessage::ErrnoLogMessage(const char* file,
    752                                  int line,
    753                                  LogSeverity severity,
    754                                  SystemErrorCode err)
    755     : err_(err),
    756       log_message_(file, line, severity) {
    757 }
    758 
    759 ErrnoLogMessage::~ErrnoLogMessage() {
    760   stream() << ": " << SystemErrorCodeToString(err_);
    761 }
    762 #endif  // OS_WIN
    763 
    764 void CloseLogFile() {
    765   LoggingLock logging_lock;
    766   CloseLogFileUnlocked();
    767 }
    768 
    769 void RawLog(int level, const char* message) {
    770   if (level >= min_log_level) {
    771     size_t bytes_written = 0;
    772     const size_t message_len = strlen(message);
    773     int rv;
    774     while (bytes_written < message_len) {
    775       rv = HANDLE_EINTR(
    776           write(STDERR_FILENO, message + bytes_written,
    777                 message_len - bytes_written));
    778       if (rv < 0) {
    779         // Give up, nothing we can do now.
    780         break;
    781       }
    782       bytes_written += rv;
    783     }
    784 
    785     if (message_len > 0 && message[message_len - 1] != '\n') {
    786       do {
    787         rv = HANDLE_EINTR(write(STDERR_FILENO, "\n", 1));
    788         if (rv < 0) {
    789           // Give up, nothing we can do now.
    790           break;
    791         }
    792       } while (rv != 1);
    793     }
    794   }
    795 
    796   if (level == LOG_FATAL)
    797     base::debug::BreakDebugger();
    798 }
    799 
    800 // This was defined at the beginning of this file.
    801 #undef write
    802 
    803 #if defined(OS_WIN)
    804 std::wstring GetLogFileFullPath() {
    805   if (log_file_name)
    806     return *log_file_name;
    807   return std::wstring();
    808 }
    809 #endif
    810 
    811 }  // namespace logging
    812 
    813 std::ostream& std::operator<<(std::ostream& out, const wchar_t* wstr) {
    814   return out << base::WideToUTF8(std::wstring(wstr));
    815 }
    816