logging.h revision 731df977c0511bca2206b5f333555b1205ff1f43
1// Copyright (c) 2006-2008 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#ifndef BASE_LOGGING_H_ 6#define BASE_LOGGING_H_ 7#pragma once 8 9#include <string> 10#include <cstring> 11#include <sstream> 12 13#include "base/basictypes.h" 14 15// 16// Optional message capabilities 17// ----------------------------- 18// Assertion failed messages and fatal errors are displayed in a dialog box 19// before the application exits. However, running this UI creates a message 20// loop, which causes application messages to be processed and potentially 21// dispatched to existing application windows. Since the application is in a 22// bad state when this assertion dialog is displayed, these messages may not 23// get processed and hang the dialog, or the application might go crazy. 24// 25// Therefore, it can be beneficial to display the error dialog in a separate 26// process from the main application. When the logging system needs to display 27// a fatal error dialog box, it will look for a program called 28// "DebugMessage.exe" in the same directory as the application executable. It 29// will run this application with the message as the command line, and will 30// not include the name of the application as is traditional for easier 31// parsing. 32// 33// The code for DebugMessage.exe is only one line. In WinMain, do: 34// MessageBox(NULL, GetCommandLineW(), L"Fatal Error", 0); 35// 36// If DebugMessage.exe is not found, the logging code will use a normal 37// MessageBox, potentially causing the problems discussed above. 38 39 40// Instructions 41// ------------ 42// 43// Make a bunch of macros for logging. The way to log things is to stream 44// things to LOG(<a particular severity level>). E.g., 45// 46// LOG(INFO) << "Found " << num_cookies << " cookies"; 47// 48// You can also do conditional logging: 49// 50// LOG_IF(INFO, num_cookies > 10) << "Got lots of cookies"; 51// 52// The above will cause log messages to be output on the 1st, 11th, 21st, ... 53// times it is executed. Note that the special COUNTER value is used to 54// identify which repetition is happening. 55// 56// The CHECK(condition) macro is active in both debug and release builds and 57// effectively performs a LOG(FATAL) which terminates the process and 58// generates a crashdump unless a debugger is attached. 59// 60// There are also "debug mode" logging macros like the ones above: 61// 62// DLOG(INFO) << "Found cookies"; 63// 64// DLOG_IF(INFO, num_cookies > 10) << "Got lots of cookies"; 65// 66// All "debug mode" logging is compiled away to nothing for non-debug mode 67// compiles. LOG_IF and development flags also work well together 68// because the code can be compiled away sometimes. 69// 70// We also have 71// 72// LOG_ASSERT(assertion); 73// DLOG_ASSERT(assertion); 74// 75// which is syntactic sugar for {,D}LOG_IF(FATAL, assert fails) << assertion; 76// 77// There are "verbose level" logging macros. They look like 78// 79// VLOG(1) << "I'm printed when you run the program with --v=1 or more"; 80// VLOG(2) << "I'm printed when you run the program with --v=2 or more"; 81// 82// These always log at the INFO log level (when they log at all). 83// The verbose logging can also be turned on module-by-module. For instance, 84// --vmodule=profile=2,icon_loader=1,browser_*=3 --v=0 85// will cause: 86// a. VLOG(2) and lower messages to be printed from profile.{h,cc} 87// b. VLOG(1) and lower messages to be printed from icon_loader.{h,cc} 88// c. VLOG(3) and lower messages to be printed from files prefixed with 89// "browser" 90// d. VLOG(0) and lower messages to be printed from elsewhere 91// 92// The wildcarding functionality shown by (c) supports both '*' (match 93// 0 or more characters) and '?' (match any single character) wildcards. 94// 95// There's also VLOG_IS_ON(n) "verbose level" condition macro. To be used as 96// 97// if (VLOG_IS_ON(2)) { 98// // do some logging preparation and logging 99// // that can't be accomplished with just VLOG(2) << ...; 100// } 101// 102// There is also a VLOG_IF "verbose level" condition macro for sample 103// cases, when some extra computation and preparation for logs is not 104// needed. 105// 106// VLOG_IF(1, (size > 1024)) 107// << "I'm printed when size is more than 1024 and when you run the " 108// "program with --v=1 or more"; 109// 110// We also override the standard 'assert' to use 'DLOG_ASSERT'. 111// 112// Lastly, there is: 113// 114// PLOG(ERROR) << "Couldn't do foo"; 115// DPLOG(ERROR) << "Couldn't do foo"; 116// PLOG_IF(ERROR, cond) << "Couldn't do foo"; 117// DPLOG_IF(ERROR, cond) << "Couldn't do foo"; 118// PCHECK(condition) << "Couldn't do foo"; 119// DPCHECK(condition) << "Couldn't do foo"; 120// 121// which append the last system error to the message in string form (taken from 122// GetLastError() on Windows and errno on POSIX). 123// 124// The supported severity levels for macros that allow you to specify one 125// are (in increasing order of severity) INFO, WARNING, ERROR, ERROR_REPORT, 126// and FATAL. 127// 128// Very important: logging a message at the FATAL severity level causes 129// the program to terminate (after the message is logged). 130// 131// Note the special severity of ERROR_REPORT only available/relevant in normal 132// mode, which displays error dialog without terminating the program. There is 133// no error dialog for severity ERROR or below in normal mode. 134// 135// There is also the special severity of DFATAL, which logs FATAL in 136// debug mode, ERROR in normal mode. 137 138namespace logging { 139 140// Where to record logging output? A flat file and/or system debug log via 141// OutputDebugString. Defaults on Windows to LOG_ONLY_TO_FILE, and on 142// POSIX to LOG_ONLY_TO_SYSTEM_DEBUG_LOG (aka stderr). 143enum LoggingDestination { LOG_NONE, 144 LOG_ONLY_TO_FILE, 145 LOG_ONLY_TO_SYSTEM_DEBUG_LOG, 146 LOG_TO_BOTH_FILE_AND_SYSTEM_DEBUG_LOG }; 147 148// Indicates that the log file should be locked when being written to. 149// Often, there is no locking, which is fine for a single threaded program. 150// If logging is being done from multiple threads or there can be more than 151// one process doing the logging, the file should be locked during writes to 152// make each log outut atomic. Other writers will block. 153// 154// All processes writing to the log file must have their locking set for it to 155// work properly. Defaults to DONT_LOCK_LOG_FILE. 156enum LogLockingState { LOCK_LOG_FILE, DONT_LOCK_LOG_FILE }; 157 158// On startup, should we delete or append to an existing log file (if any)? 159// Defaults to APPEND_TO_OLD_LOG_FILE. 160enum OldFileDeletionState { DELETE_OLD_LOG_FILE, APPEND_TO_OLD_LOG_FILE }; 161 162// TODO(avi): do we want to do a unification of character types here? 163#if defined(OS_WIN) 164typedef wchar_t PathChar; 165#else 166typedef char PathChar; 167#endif 168 169// Define different names for the BaseInitLoggingImpl() function depending on 170// whether NDEBUG is defined or not so that we'll fail to link if someone tries 171// to compile logging.cc with NDEBUG but includes logging.h without defining it, 172// or vice versa. 173#if NDEBUG 174#define BaseInitLoggingImpl BaseInitLoggingImpl_built_with_NDEBUG 175#else 176#define BaseInitLoggingImpl BaseInitLoggingImpl_built_without_NDEBUG 177#endif 178 179// Implementation of the InitLogging() method declared below. We use a 180// more-specific name so we can #define it above without affecting other code 181// that has named stuff "InitLogging". 182void BaseInitLoggingImpl(const PathChar* log_file, 183 LoggingDestination logging_dest, 184 LogLockingState lock_log, 185 OldFileDeletionState delete_old); 186 187// Sets the log file name and other global logging state. Calling this function 188// is recommended, and is normally done at the beginning of application init. 189// If you don't call it, all the flags will be initialized to their default 190// values, and there is a race condition that may leak a critical section 191// object if two threads try to do the first log at the same time. 192// See the definition of the enums above for descriptions and default values. 193// 194// The default log file is initialized to "debug.log" in the application 195// directory. You probably don't want this, especially since the program 196// directory may not be writable on an enduser's system. 197inline void InitLogging(const PathChar* log_file, 198 LoggingDestination logging_dest, 199 LogLockingState lock_log, 200 OldFileDeletionState delete_old) { 201 BaseInitLoggingImpl(log_file, logging_dest, lock_log, delete_old); 202} 203 204// Sets the log level. Anything at or above this level will be written to the 205// log file/displayed to the user (if applicable). Anything below this level 206// will be silently ignored. The log level defaults to 0 (everything is logged) 207// if this function is not called. 208void SetMinLogLevel(int level); 209 210// Gets the current log level. 211int GetMinLogLevel(); 212 213// Gets the current vlog level for the given file (usually taken from 214// __FILE__). 215 216// Note that |N| is the size *with* the null terminator. 217int GetVlogLevelHelper(const char* file_start, size_t N); 218 219template <size_t N> 220int GetVlogLevel(const char (&file)[N]) { 221 return GetVlogLevelHelper(file, N); 222} 223 224// Sets the common items you want to be prepended to each log message. 225// process and thread IDs default to off, the timestamp defaults to on. 226// If this function is not called, logging defaults to writing the timestamp 227// only. 228void SetLogItems(bool enable_process_id, bool enable_thread_id, 229 bool enable_timestamp, bool enable_tickcount); 230 231// Sets whether or not you'd like to see fatal debug messages popped up in 232// a dialog box or not. 233// Dialogs are not shown by default. 234void SetShowErrorDialogs(bool enable_dialogs); 235 236// Sets the Log Assert Handler that will be used to notify of check failures. 237// The default handler shows a dialog box and then terminate the process, 238// however clients can use this function to override with their own handling 239// (e.g. a silent one for Unit Tests) 240typedef void (*LogAssertHandlerFunction)(const std::string& str); 241void SetLogAssertHandler(LogAssertHandlerFunction handler); 242// Sets the Log Report Handler that will be used to notify of check failures 243// in non-debug mode. The default handler shows a dialog box and continues 244// the execution, however clients can use this function to override with their 245// own handling. 246typedef void (*LogReportHandlerFunction)(const std::string& str); 247void SetLogReportHandler(LogReportHandlerFunction handler); 248 249// Sets the Log Message Handler that gets passed every log message before 250// it's sent to other log destinations (if any). 251// Returns true to signal that it handled the message and the message 252// should not be sent to other log destinations. 253typedef bool (*LogMessageHandlerFunction)(int severity, const std::string& str); 254void SetLogMessageHandler(LogMessageHandlerFunction handler); 255 256typedef int LogSeverity; 257const LogSeverity LOG_INFO = 0; 258const LogSeverity LOG_WARNING = 1; 259const LogSeverity LOG_ERROR = 2; 260const LogSeverity LOG_ERROR_REPORT = 3; 261const LogSeverity LOG_FATAL = 4; 262const LogSeverity LOG_NUM_SEVERITIES = 5; 263 264// LOG_DFATAL is LOG_FATAL in debug mode, ERROR in normal mode 265#ifdef NDEBUG 266const LogSeverity LOG_DFATAL = LOG_ERROR; 267#else 268const LogSeverity LOG_DFATAL = LOG_FATAL; 269#endif 270 271// A few definitions of macros that don't generate much code. These are used 272// by LOG() and LOG_IF, etc. Since these are used all over our code, it's 273// better to have compact code for these operations. 274#define COMPACT_GOOGLE_LOG_EX_INFO(ClassName, ...) \ 275 logging::ClassName(__FILE__, __LINE__, logging::LOG_INFO , ##__VA_ARGS__) 276#define COMPACT_GOOGLE_LOG_EX_WARNING(ClassName, ...) \ 277 logging::ClassName(__FILE__, __LINE__, logging::LOG_WARNING , ##__VA_ARGS__) 278#define COMPACT_GOOGLE_LOG_EX_ERROR(ClassName, ...) \ 279 logging::ClassName(__FILE__, __LINE__, logging::LOG_ERROR , ##__VA_ARGS__) 280#define COMPACT_GOOGLE_LOG_EX_ERROR_REPORT(ClassName, ...) \ 281 logging::ClassName(__FILE__, __LINE__, \ 282 logging::LOG_ERROR_REPORT , ##__VA_ARGS__) 283#define COMPACT_GOOGLE_LOG_EX_FATAL(ClassName, ...) \ 284 logging::ClassName(__FILE__, __LINE__, logging::LOG_FATAL , ##__VA_ARGS__) 285#define COMPACT_GOOGLE_LOG_EX_DFATAL(ClassName, ...) \ 286 logging::ClassName(__FILE__, __LINE__, logging::LOG_DFATAL , ##__VA_ARGS__) 287 288#define COMPACT_GOOGLE_LOG_INFO \ 289 COMPACT_GOOGLE_LOG_EX_INFO(LogMessage) 290#define COMPACT_GOOGLE_LOG_WARNING \ 291 COMPACT_GOOGLE_LOG_EX_WARNING(LogMessage) 292#define COMPACT_GOOGLE_LOG_ERROR \ 293 COMPACT_GOOGLE_LOG_EX_ERROR(LogMessage) 294#define COMPACT_GOOGLE_LOG_ERROR_REPORT \ 295 COMPACT_GOOGLE_LOG_EX_ERROR_REPORT(LogMessage) 296#define COMPACT_GOOGLE_LOG_FATAL \ 297 COMPACT_GOOGLE_LOG_EX_FATAL(LogMessage) 298#define COMPACT_GOOGLE_LOG_DFATAL \ 299 COMPACT_GOOGLE_LOG_EX_DFATAL(LogMessage) 300 301// wingdi.h defines ERROR to be 0. When we call LOG(ERROR), it gets 302// substituted with 0, and it expands to COMPACT_GOOGLE_LOG_0. To allow us 303// to keep using this syntax, we define this macro to do the same thing 304// as COMPACT_GOOGLE_LOG_ERROR, and also define ERROR the same way that 305// the Windows SDK does for consistency. 306#define ERROR 0 307#define COMPACT_GOOGLE_LOG_EX_0(ClassName, ...) \ 308 COMPACT_GOOGLE_LOG_EX_ERROR(ClassName , ##__VA_ARGS__) 309#define COMPACT_GOOGLE_LOG_0 COMPACT_GOOGLE_LOG_ERROR 310// Needed for LOG_IS_ON(ERROR). 311const LogSeverity LOG_0 = LOG_ERROR; 312 313#define LOG_IS_ON(severity) \ 314 ((::logging::LOG_ ## severity) >= ::logging::GetMinLogLevel()) 315 316// We can't do any caching tricks with VLOG_IS_ON() like the 317// google-glog version since it requires GCC extensions. This means 318// that using the v-logging functions in conjunction with --vmodule 319// may be slow. 320#define VLOG_IS_ON(verboselevel) \ 321 ((verboselevel) <= ::logging::GetVlogLevel(__FILE__)) 322 323// Helper macro which avoids evaluating the arguments to a stream if 324// the condition doesn't hold. 325#define LAZY_STREAM(stream, condition) \ 326 !(condition) ? (void) 0 : ::logging::LogMessageVoidify() & (stream) 327 328// We use the preprocessor's merging operator, "##", so that, e.g., 329// LOG(INFO) becomes the token COMPACT_GOOGLE_LOG_INFO. There's some funny 330// subtle difference between ostream member streaming functions (e.g., 331// ostream::operator<<(int) and ostream non-member streaming functions 332// (e.g., ::operator<<(ostream&, string&): it turns out that it's 333// impossible to stream something like a string directly to an unnamed 334// ostream. We employ a neat hack by calling the stream() member 335// function of LogMessage which seems to avoid the problem. 336#define LOG_STREAM(severity) COMPACT_GOOGLE_LOG_ ## severity.stream() 337 338#define LOG(severity) LAZY_STREAM(LOG_STREAM(severity), LOG_IS_ON(severity)) 339#define LOG_IF(severity, condition) \ 340 LAZY_STREAM(LOG_STREAM(severity), LOG_IS_ON(severity) && (condition)) 341 342#define SYSLOG(severity) LOG(severity) 343#define SYSLOG_IF(severity, condition) LOG_IF(severity, condition) 344 345#define VLOG(verboselevel) LOG_IF(INFO, VLOG_IS_ON(verboselevel)) 346#define VLOG_IF(verboselevel, condition) \ 347 LOG_IF(INFO, VLOG_IS_ON(verboselevel) && (condition)) 348 349// TODO(akalin): Add more VLOG variants, e.g. VPLOG. 350 351#define LOG_ASSERT(condition) \ 352 LOG_IF(FATAL, !(condition)) << "Assert failed: " #condition ". " 353#define SYSLOG_ASSERT(condition) \ 354 SYSLOG_IF(FATAL, !(condition)) << "Assert failed: " #condition ". " 355 356#if defined(OS_WIN) 357#define LOG_GETLASTERROR_STREAM(severity) \ 358 COMPACT_GOOGLE_LOG_EX_ ## severity(Win32ErrorLogMessage, \ 359 ::logging::GetLastSystemErrorCode()).stream() 360#define LOG_GETLASTERROR(severity) \ 361 LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity), LOG_IS_ON(severity)) 362#define LOG_GETLASTERROR_MODULE_STREAM(severity, module) \ 363 COMPACT_GOOGLE_LOG_EX_ ## severity(Win32ErrorLogMessage, \ 364 ::logging::GetLastSystemErrorCode(), module).stream() 365#define LOG_GETLASTERROR_MODULE(severity, module) \ 366 LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity, module), \ 367 LOG_IS_ON(severity)) 368// PLOG_STREAM is used by PLOG, which is the usual error logging macro 369// for each platform. 370#define PLOG_STREAM(severity) LOG_GETLASTERROR_STREAM(severity) 371#elif defined(OS_POSIX) 372#define LOG_ERRNO_STREAM(severity) \ 373 COMPACT_GOOGLE_LOG_EX_ ## severity(ErrnoLogMessage, \ 374 ::logging::GetLastSystemErrorCode()).stream() 375#define LOG_ERRNO(severity) \ 376 LAZY_STREAM(LOG_ERRNO_STREAM(severity), LOG_IS_ON(severity)) 377// PLOG_STREAM is used by PLOG, which is the usual error logging macro 378// for each platform. 379#define PLOG_STREAM(severity) LOG_ERRNO_STREAM(severity) 380// TODO(tschmelcher): Should we add OSStatus logging for Mac? 381#endif 382 383#define PLOG(severity) \ 384 LAZY_STREAM(PLOG_STREAM(severity), LOG_IS_ON(severity)) 385 386#define PLOG_IF(severity, condition) \ 387 LAZY_STREAM(PLOG_STREAM(severity), LOG_IS_ON(severity) && (condition)) 388 389// CHECK dies with a fatal error if condition is not true. It is *not* 390// controlled by NDEBUG, so the check will be executed regardless of 391// compilation mode. 392// 393// We make sure CHECK et al. always evaluates their arguments, as 394// doing CHECK(FunctionWithSideEffect()) is a common idiom. 395// 396// TODO(akalin): Fix the problem where if the min log level is > 397// FATAL, CHECK() et al. won't terminate the program. 398#define CHECK(condition) \ 399 LAZY_STREAM(LOG_STREAM(FATAL), !(condition)) \ 400 << "Check failed: " #condition ". " 401 402#define PCHECK(condition) \ 403 LAZY_STREAM(PLOG_STREAM(FATAL), !(condition)) \ 404 << "Check failed: " #condition ". " 405 406// A container for a string pointer which can be evaluated to a bool - 407// true iff the pointer is NULL. 408struct CheckOpString { 409 CheckOpString(std::string* str) : str_(str) { } 410 // No destructor: if str_ is non-NULL, we're about to LOG(FATAL), 411 // so there's no point in cleaning up str_. 412 operator bool() const { return str_ != NULL; } 413 std::string* str_; 414}; 415 416// Build the error message string. This is separate from the "Impl" 417// function template because it is not performance critical and so can 418// be out of line, while the "Impl" code should be inline. 419template<class t1, class t2> 420std::string* MakeCheckOpString(const t1& v1, const t2& v2, const char* names) { 421 std::ostringstream ss; 422 ss << names << " (" << v1 << " vs. " << v2 << ")"; 423 std::string* msg = new std::string(ss.str()); 424 return msg; 425} 426 427// MSVC doesn't like complex extern templates and DLLs. 428#if !defined(COMPILER_MSVC) 429// Commonly used instantiations of MakeCheckOpString<>. Explicitly instantiated 430// in logging.cc. 431extern template std::string* MakeCheckOpString<int, int>( 432 const int&, const int&, const char* names); 433extern template std::string* MakeCheckOpString<unsigned long, unsigned long>( 434 const unsigned long&, const unsigned long&, const char* names); 435extern template std::string* MakeCheckOpString<unsigned long, unsigned int>( 436 const unsigned long&, const unsigned int&, const char* names); 437extern template std::string* MakeCheckOpString<unsigned int, unsigned long>( 438 const unsigned int&, const unsigned long&, const char* names); 439extern template std::string* MakeCheckOpString<std::string, std::string>( 440 const std::string&, const std::string&, const char* name); 441#endif 442 443// Helper macro for binary operators. 444// Don't use this macro directly in your code, use CHECK_EQ et al below. 445// 446// TODO(akalin): Rewrite this so that constructs like if (...) 447// CHECK_EQ(...) else { ... } work properly. 448#define CHECK_OP(name, op, val1, val2) \ 449 if (logging::CheckOpString _result = \ 450 logging::Check##name##Impl((val1), (val2), \ 451 #val1 " " #op " " #val2)) \ 452 logging::LogMessage(__FILE__, __LINE__, _result).stream() 453 454// Helper functions for string comparisons. 455// To avoid bloat, the definitions are in logging.cc. 456// 457// TODO(akalin): Actually have the implementations in logging.cc, or 458// remove these. 459#define DECLARE_CHECK_STROP_IMPL(func, expected) \ 460 std::string* Check##func##expected##Impl(const char* s1, \ 461 const char* s2, \ 462 const char* names); 463DECLARE_CHECK_STROP_IMPL(strcmp, true) 464DECLARE_CHECK_STROP_IMPL(strcmp, false) 465DECLARE_CHECK_STROP_IMPL(_stricmp, true) 466DECLARE_CHECK_STROP_IMPL(_stricmp, false) 467#undef DECLARE_CHECK_STROP_IMPL 468 469// Helper macro for string comparisons. 470// Don't use this macro directly in your code, use CHECK_STREQ et al below. 471#define CHECK_STROP(func, op, expected, s1, s2) \ 472 while (CheckOpString _result = \ 473 logging::Check##func##expected##Impl((s1), (s2), \ 474 #s1 " " #op " " #s2)) \ 475 LOG(FATAL) << *_result.str_ 476 477// String (char*) equality/inequality checks. 478// CASE versions are case-insensitive. 479// 480// Note that "s1" and "s2" may be temporary strings which are destroyed 481// by the compiler at the end of the current "full expression" 482// (e.g. CHECK_STREQ(Foo().c_str(), Bar().c_str())). 483 484#define CHECK_STREQ(s1, s2) CHECK_STROP(strcmp, ==, true, s1, s2) 485#define CHECK_STRNE(s1, s2) CHECK_STROP(strcmp, !=, false, s1, s2) 486#define CHECK_STRCASEEQ(s1, s2) CHECK_STROP(_stricmp, ==, true, s1, s2) 487#define CHECK_STRCASENE(s1, s2) CHECK_STROP(_stricmp, !=, false, s1, s2) 488 489#define CHECK_INDEX(I,A) CHECK(I < (sizeof(A)/sizeof(A[0]))) 490#define CHECK_BOUND(B,A) CHECK(B <= (sizeof(A)/sizeof(A[0]))) 491 492#define CHECK_EQ(val1, val2) CHECK_OP(EQ, ==, val1, val2) 493#define CHECK_NE(val1, val2) CHECK_OP(NE, !=, val1, val2) 494#define CHECK_LE(val1, val2) CHECK_OP(LE, <=, val1, val2) 495#define CHECK_LT(val1, val2) CHECK_OP(LT, < , val1, val2) 496#define CHECK_GE(val1, val2) CHECK_OP(GE, >=, val1, val2) 497#define CHECK_GT(val1, val2) CHECK_OP(GT, > , val1, val2) 498 499// http://crbug.com/16512 is open for a real fix for this. For now, Windows 500// uses OFFICIAL_BUILD and other platforms use the branding flag when NDEBUG is 501// defined. 502#if ( defined(OS_WIN) && defined(OFFICIAL_BUILD)) || \ 503 (!defined(OS_WIN) && defined(NDEBUG) && defined(GOOGLE_CHROME_BUILD)) 504// Used by unit tests. 505#define LOGGING_IS_OFFICIAL_BUILD 506 507// In order to have optimized code for official builds, remove DLOGs and 508// DCHECKs. 509#define ENABLE_DLOG 0 510#define ENABLE_DCHECK 0 511 512#elif defined(NDEBUG) 513// Otherwise, if we're a release build, remove DLOGs but not DCHECKs 514// (since those can still be turned on via a command-line flag). 515#define ENABLE_DLOG 0 516#define ENABLE_DCHECK 1 517 518#else 519// Otherwise, we're a debug build so enable DLOGs and DCHECKs. 520#define ENABLE_DLOG 1 521#define ENABLE_DCHECK 1 522#endif 523 524// Definitions for DLOG et al. 525 526#if ENABLE_DLOG 527 528#define DLOG_IF(severity, condition) LOG_IF(severity, condition) 529#define DLOG_ASSERT(condition) LOG_ASSERT(condition) 530#define DPLOG_IF(severity, condition) PLOG_IF(severity, condition) 531#define DVLOG_IF(verboselevel, condition) VLOG_IF(verboselevel, condition) 532 533#else // ENABLE_DLOG 534 535// If ENABLE_DLOG is off, we want to avoid emitting any references to 536// |condition| (which may reference a variable defined only if NDEBUG 537// is not defined). Contrast this with DCHECK et al., which has 538// different behavior. 539 540#define DLOG_EAT_STREAM_PARAMETERS \ 541 true ? (void) 0 : ::logging::LogMessageVoidify() & LOG_STREAM(FATAL) 542 543#define DLOG_IF(severity, condition) DLOG_EAT_STREAM_PARAMETERS 544#define DLOG_ASSERT(condition) DLOG_EAT_STREAM_PARAMETERS 545#define DPLOG_IF(severity, condition) DLOG_EAT_STREAM_PARAMETERS 546#define DVLOG_IF(verboselevel, condition) DLOG_EAT_STREAM_PARAMETERS 547 548#endif // ENABLE_DLOG 549 550// DEBUG_MODE is for uses like 551// if (DEBUG_MODE) foo.CheckThatFoo(); 552// instead of 553// #ifndef NDEBUG 554// foo.CheckThatFoo(); 555// #endif 556// 557// We tie its state to ENABLE_DLOG. 558enum { DEBUG_MODE = ENABLE_DLOG }; 559 560#undef ENABLE_DLOG 561 562#define DLOG_IS_ON(severity) (::logging::DEBUG_MODE && LOG_IS_ON(severity)) 563 564#define DLOG(severity) \ 565 LAZY_STREAM(LOG_STREAM(severity), DLOG_IS_ON(severity)) 566 567#if defined(OS_WIN) 568#define DLOG_GETLASTERROR(severity) \ 569 LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity), DLOG_IS_ON(severity)) 570#define DLOG_GETLASTERROR_MODULE(severity, module) \ 571 LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity, module), \ 572 DLOG_IS_ON(severity)) 573#elif defined(OS_POSIX) 574#define DLOG_ERRNO(severity) \ 575 LAZY_STREAM(LOG_ERRNO_STREAM(severity), DLOG_IS_ON(severity)) 576#endif 577 578#define DPLOG(severity) \ 579 LAZY_STREAM(PLOG_STREAM(severity), DLOG_IS_ON(severity)) 580 581#define DVLOG(verboselevel) DLOG_IF(INFO, VLOG_IS_ON(verboselevel)) 582 583// Definitions for DCHECK et al. 584 585#if ENABLE_DCHECK 586 587#if defined(NDEBUG) 588 589// Set to true in InitLogging when we want to enable the dchecks in release. 590extern bool g_enable_dcheck; 591#define DCHECK_IS_ON() (::logging::g_enable_dcheck) 592#define DCHECK_SEVERITY ERROR_REPORT 593const LogSeverity LOG_DCHECK = LOG_ERROR_REPORT; 594 595#else // defined(NDEBUG) 596 597// On a regular debug build, we want to have DCHECKS enabled. 598#define DCHECK_IS_ON() (true) 599#define DCHECK_SEVERITY FATAL 600const LogSeverity LOG_DCHECK = LOG_FATAL; 601 602#endif // defined(NDEBUG) 603 604#else // ENABLE_DCHECK 605 606#define DCHECK_IS_ON() (false) 607#define DCHECK_SEVERITY FATAL 608const LogSeverity LOG_DCHECK = LOG_FATAL; 609 610#endif // ENABLE_DCHECK 611 612// Unlike CHECK et al., DCHECK et al. *does* evaluate their arguments 613// lazily. 614 615// DCHECK et al. also make sure to reference |condition| regardless of 616// whether DCHECKs are enabled; this is so that we don't get unused 617// variable warnings if the only use of a variable is in a DCHECK. 618// This behavior is different from DLOG_IF et al. 619 620#define DCHECK(condition) \ 621 !DCHECK_IS_ON() ? (void) 0 : \ 622 LOG_IF(DCHECK_SEVERITY, !(condition)) \ 623 << "Check failed: " #condition ". " 624 625#define DPCHECK(condition) \ 626 !DCHECK_IS_ON() ? (void) 0 : \ 627 PLOG_IF(DCHECK_SEVERITY, !(condition)) \ 628 << "Check failed: " #condition ". " 629 630// Helper macro for binary operators. 631// Don't use this macro directly in your code, use DCHECK_EQ et al below. 632#define DCHECK_OP(name, op, val1, val2) \ 633 if (DLOG_IS_ON(DCHECK_SEVERITY)) \ 634 if (logging::CheckOpString _result = \ 635 logging::Check##name##Impl((val1), (val2), \ 636 #val1 " " #op " " #val2)) \ 637 logging::LogMessage( \ 638 __FILE__, __LINE__, ::logging::LOG_DCHECK, \ 639 _result).stream() 640 641// Equality/Inequality checks - compare two values, and log a LOG_FATAL message 642// including the two values when the result is not as expected. The values 643// must have operator<<(ostream, ...) defined. 644// 645// You may append to the error message like so: 646// DCHECK_NE(1, 2) << ": The world must be ending!"; 647// 648// We are very careful to ensure that each argument is evaluated exactly 649// once, and that anything which is legal to pass as a function argument is 650// legal here. In particular, the arguments may be temporary expressions 651// which will end up being destroyed at the end of the apparent statement, 652// for example: 653// DCHECK_EQ(string("abc")[1], 'b'); 654// 655// WARNING: These may not compile correctly if one of the arguments is a pointer 656// and the other is NULL. To work around this, simply static_cast NULL to the 657// type of the desired pointer. 658 659#define DCHECK_EQ(val1, val2) DCHECK_OP(EQ, ==, val1, val2) 660#define DCHECK_NE(val1, val2) DCHECK_OP(NE, !=, val1, val2) 661#define DCHECK_LE(val1, val2) DCHECK_OP(LE, <=, val1, val2) 662#define DCHECK_LT(val1, val2) DCHECK_OP(LT, < , val1, val2) 663#define DCHECK_GE(val1, val2) DCHECK_OP(GE, >=, val1, val2) 664#define DCHECK_GT(val1, val2) DCHECK_OP(GT, > , val1, val2) 665 666// Helper macro for string comparisons. 667// Don't use this macro directly in your code, use DCHECK_STREQ et al below. 668#define DCHECK_STROP(func, op, expected, s1, s2) \ 669 if (DCHECK_IS_ON()) CHECK_STROP(func, op, expected, s1, s2) 670 671// String (char*) equality/inequality checks. 672// CASE versions are case-insensitive. 673// 674// Note that "s1" and "s2" may be temporary strings which are destroyed 675// by the compiler at the end of the current "full expression" 676// (e.g. DCHECK_STREQ(Foo().c_str(), Bar().c_str())). 677 678#define DCHECK_STREQ(s1, s2) DCHECK_STROP(strcmp, ==, true, s1, s2) 679#define DCHECK_STRNE(s1, s2) DCHECK_STROP(strcmp, !=, false, s1, s2) 680#define DCHECK_STRCASEEQ(s1, s2) DCHECK_STROP(_stricmp, ==, true, s1, s2) 681#define DCHECK_STRCASENE(s1, s2) DCHECK_STROP(_stricmp, !=, false, s1, s2) 682 683#define DCHECK_INDEX(I,A) DCHECK(I < (sizeof(A)/sizeof(A[0]))) 684#define DCHECK_BOUND(B,A) DCHECK(B <= (sizeof(A)/sizeof(A[0]))) 685 686// Helper functions for CHECK_OP macro. 687// The (int, int) specialization works around the issue that the compiler 688// will not instantiate the template version of the function on values of 689// unnamed enum type - see comment below. 690#define DEFINE_CHECK_OP_IMPL(name, op) \ 691 template <class t1, class t2> \ 692 inline std::string* Check##name##Impl(const t1& v1, const t2& v2, \ 693 const char* names) { \ 694 if (v1 op v2) return NULL; \ 695 else return MakeCheckOpString(v1, v2, names); \ 696 } \ 697 inline std::string* Check##name##Impl(int v1, int v2, const char* names) { \ 698 if (v1 op v2) return NULL; \ 699 else return MakeCheckOpString(v1, v2, names); \ 700 } 701DEFINE_CHECK_OP_IMPL(EQ, ==) 702DEFINE_CHECK_OP_IMPL(NE, !=) 703DEFINE_CHECK_OP_IMPL(LE, <=) 704DEFINE_CHECK_OP_IMPL(LT, < ) 705DEFINE_CHECK_OP_IMPL(GE, >=) 706DEFINE_CHECK_OP_IMPL(GT, > ) 707#undef DEFINE_CHECK_OP_IMPL 708 709#define NOTREACHED() DCHECK(false) 710 711// Redefine the standard assert to use our nice log files 712#undef assert 713#define assert(x) DLOG_ASSERT(x) 714 715// This class more or less represents a particular log message. You 716// create an instance of LogMessage and then stream stuff to it. 717// When you finish streaming to it, ~LogMessage is called and the 718// full message gets streamed to the appropriate destination. 719// 720// You shouldn't actually use LogMessage's constructor to log things, 721// though. You should use the LOG() macro (and variants thereof) 722// above. 723class LogMessage { 724 public: 725 LogMessage(const char* file, int line, LogSeverity severity, int ctr); 726 727 // Two special constructors that generate reduced amounts of code at 728 // LOG call sites for common cases. 729 // 730 // Used for LOG(INFO): Implied are: 731 // severity = LOG_INFO, ctr = 0 732 // 733 // Using this constructor instead of the more complex constructor above 734 // saves a couple of bytes per call site. 735 LogMessage(const char* file, int line); 736 737 // Used for LOG(severity) where severity != INFO. Implied 738 // are: ctr = 0 739 // 740 // Using this constructor instead of the more complex constructor above 741 // saves a couple of bytes per call site. 742 LogMessage(const char* file, int line, LogSeverity severity); 743 744 // A special constructor used for check failures. 745 // Implied severity = LOG_FATAL 746 LogMessage(const char* file, int line, const CheckOpString& result); 747 748 // A special constructor used for check failures, with the option to 749 // specify severity. 750 LogMessage(const char* file, int line, LogSeverity severity, 751 const CheckOpString& result); 752 753 ~LogMessage(); 754 755 std::ostream& stream() { return stream_; } 756 757 private: 758 void Init(const char* file, int line); 759 760 LogSeverity severity_; 761 std::ostringstream stream_; 762 size_t message_start_; // Offset of the start of the message (past prefix 763 // info). 764#if defined(OS_WIN) 765 // Stores the current value of GetLastError in the constructor and restores 766 // it in the destructor by calling SetLastError. 767 // This is useful since the LogMessage class uses a lot of Win32 calls 768 // that will lose the value of GLE and the code that called the log function 769 // will have lost the thread error value when the log call returns. 770 class SaveLastError { 771 public: 772 SaveLastError(); 773 ~SaveLastError(); 774 775 unsigned long get_error() const { return last_error_; } 776 777 protected: 778 unsigned long last_error_; 779 }; 780 781 SaveLastError last_error_; 782#endif 783 784 DISALLOW_COPY_AND_ASSIGN(LogMessage); 785}; 786 787// A non-macro interface to the log facility; (useful 788// when the logging level is not a compile-time constant). 789inline void LogAtLevel(int const log_level, std::string const &msg) { 790 LogMessage(__FILE__, __LINE__, log_level).stream() << msg; 791} 792 793// This class is used to explicitly ignore values in the conditional 794// logging macros. This avoids compiler warnings like "value computed 795// is not used" and "statement has no effect". 796class LogMessageVoidify { 797 public: 798 LogMessageVoidify() { } 799 // This has to be an operator with a precedence lower than << but 800 // higher than ?: 801 void operator&(std::ostream&) { } 802}; 803 804#if defined(OS_WIN) 805typedef unsigned long SystemErrorCode; 806#elif defined(OS_POSIX) 807typedef int SystemErrorCode; 808#endif 809 810// Alias for ::GetLastError() on Windows and errno on POSIX. Avoids having to 811// pull in windows.h just for GetLastError() and DWORD. 812SystemErrorCode GetLastSystemErrorCode(); 813 814#if defined(OS_WIN) 815// Appends a formatted system message of the GetLastError() type. 816class Win32ErrorLogMessage { 817 public: 818 Win32ErrorLogMessage(const char* file, 819 int line, 820 LogSeverity severity, 821 SystemErrorCode err, 822 const char* module); 823 824 Win32ErrorLogMessage(const char* file, 825 int line, 826 LogSeverity severity, 827 SystemErrorCode err); 828 829 std::ostream& stream() { return log_message_.stream(); } 830 831 // Appends the error message before destructing the encapsulated class. 832 ~Win32ErrorLogMessage(); 833 834 private: 835 SystemErrorCode err_; 836 // Optional name of the module defining the error. 837 const char* module_; 838 LogMessage log_message_; 839 840 DISALLOW_COPY_AND_ASSIGN(Win32ErrorLogMessage); 841}; 842#elif defined(OS_POSIX) 843// Appends a formatted system message of the errno type 844class ErrnoLogMessage { 845 public: 846 ErrnoLogMessage(const char* file, 847 int line, 848 LogSeverity severity, 849 SystemErrorCode err); 850 851 std::ostream& stream() { return log_message_.stream(); } 852 853 // Appends the error message before destructing the encapsulated class. 854 ~ErrnoLogMessage(); 855 856 private: 857 SystemErrorCode err_; 858 LogMessage log_message_; 859 860 DISALLOW_COPY_AND_ASSIGN(ErrnoLogMessage); 861}; 862#endif // OS_WIN 863 864// Closes the log file explicitly if open. 865// NOTE: Since the log file is opened as necessary by the action of logging 866// statements, there's no guarantee that it will stay closed 867// after this call. 868void CloseLogFile(); 869 870// Async signal safe logging mechanism. 871void RawLog(int level, const char* message); 872 873#define RAW_LOG(level, message) logging::RawLog(logging::LOG_ ## level, message) 874 875#define RAW_CHECK(condition) \ 876 do { \ 877 if (!(condition)) \ 878 logging::RawLog(logging::LOG_FATAL, "Check failed: " #condition "\n"); \ 879 } while (0) 880 881} // namespace logging 882 883// These functions are provided as a convenience for logging, which is where we 884// use streams (it is against Google style to use streams in other places). It 885// is designed to allow you to emit non-ASCII Unicode strings to the log file, 886// which is normally ASCII. It is relatively slow, so try not to use it for 887// common cases. Non-ASCII characters will be converted to UTF-8 by these 888// operators. 889std::ostream& operator<<(std::ostream& out, const wchar_t* wstr); 890inline std::ostream& operator<<(std::ostream& out, const std::wstring& wstr) { 891 return out << wstr.c_str(); 892} 893 894// The NOTIMPLEMENTED() macro annotates codepaths which have 895// not been implemented yet. 896// 897// The implementation of this macro is controlled by NOTIMPLEMENTED_POLICY: 898// 0 -- Do nothing (stripped by compiler) 899// 1 -- Warn at compile time 900// 2 -- Fail at compile time 901// 3 -- Fail at runtime (DCHECK) 902// 4 -- [default] LOG(ERROR) at runtime 903// 5 -- LOG(ERROR) at runtime, only once per call-site 904 905#ifndef NOTIMPLEMENTED_POLICY 906// Select default policy: LOG(ERROR) 907#define NOTIMPLEMENTED_POLICY 4 908#endif 909 910#if defined(COMPILER_GCC) 911// On Linux, with GCC, we can use __PRETTY_FUNCTION__ to get the demangled name 912// of the current function in the NOTIMPLEMENTED message. 913#define NOTIMPLEMENTED_MSG "Not implemented reached in " << __PRETTY_FUNCTION__ 914#else 915#define NOTIMPLEMENTED_MSG "NOT IMPLEMENTED" 916#endif 917 918#if NOTIMPLEMENTED_POLICY == 0 919#define NOTIMPLEMENTED() ; 920#elif NOTIMPLEMENTED_POLICY == 1 921// TODO, figure out how to generate a warning 922#define NOTIMPLEMENTED() COMPILE_ASSERT(false, NOT_IMPLEMENTED) 923#elif NOTIMPLEMENTED_POLICY == 2 924#define NOTIMPLEMENTED() COMPILE_ASSERT(false, NOT_IMPLEMENTED) 925#elif NOTIMPLEMENTED_POLICY == 3 926#define NOTIMPLEMENTED() NOTREACHED() 927#elif NOTIMPLEMENTED_POLICY == 4 928#define NOTIMPLEMENTED() LOG(ERROR) << NOTIMPLEMENTED_MSG 929#elif NOTIMPLEMENTED_POLICY == 5 930#define NOTIMPLEMENTED() do {\ 931 static int count = 0;\ 932 LOG_IF(ERROR, 0 == count++) << NOTIMPLEMENTED_MSG;\ 933} while(0) 934#endif 935 936#endif // BASE_LOGGING_H_ 937