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Diffstat (limited to 'base/logging.h')
-rw-r--r-- | base/logging.h | 952 |
1 files changed, 952 insertions, 0 deletions
diff --git a/base/logging.h b/base/logging.h new file mode 100644 index 000000000000..c18fadadb6c4 --- /dev/null +++ b/base/logging.h @@ -0,0 +1,952 @@ +// Copyright (c) 2011 The Chromium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +#ifndef BASE_LOGGING_H_ +#define BASE_LOGGING_H_ +#pragma once + +#include <cassert> +#include <string> +#include <cstring> +#include <sstream> + +#include "base/base_export.h" +#include "base/basictypes.h" +#include "build/build_config.h" + +// +// Optional message capabilities +// ----------------------------- +// Assertion failed messages and fatal errors are displayed in a dialog box +// before the application exits. However, running this UI creates a message +// loop, which causes application messages to be processed and potentially +// dispatched to existing application windows. Since the application is in a +// bad state when this assertion dialog is displayed, these messages may not +// get processed and hang the dialog, or the application might go crazy. +// +// Therefore, it can be beneficial to display the error dialog in a separate +// process from the main application. When the logging system needs to display +// a fatal error dialog box, it will look for a program called +// "DebugMessage.exe" in the same directory as the application executable. It +// will run this application with the message as the command line, and will +// not include the name of the application as is traditional for easier +// parsing. +// +// The code for DebugMessage.exe is only one line. In WinMain, do: +// MessageBox(NULL, GetCommandLineW(), L"Fatal Error", 0); +// +// If DebugMessage.exe is not found, the logging code will use a normal +// MessageBox, potentially causing the problems discussed above. + + +// Instructions +// ------------ +// +// Make a bunch of macros for logging. The way to log things is to stream +// things to LOG(<a particular severity level>). E.g., +// +// LOG(INFO) << "Found " << num_cookies << " cookies"; +// +// You can also do conditional logging: +// +// LOG_IF(INFO, num_cookies > 10) << "Got lots of cookies"; +// +// The above will cause log messages to be output on the 1st, 11th, 21st, ... +// times it is executed. Note that the special COUNTER value is used to +// identify which repetition is happening. +// +// The CHECK(condition) macro is active in both debug and release builds and +// effectively performs a LOG(FATAL) which terminates the process and +// generates a crashdump unless a debugger is attached. +// +// There are also "debug mode" logging macros like the ones above: +// +// DLOG(INFO) << "Found cookies"; +// +// DLOG_IF(INFO, num_cookies > 10) << "Got lots of cookies"; +// +// All "debug mode" logging is compiled away to nothing for non-debug mode +// compiles. LOG_IF and development flags also work well together +// because the code can be compiled away sometimes. +// +// We also have +// +// LOG_ASSERT(assertion); +// DLOG_ASSERT(assertion); +// +// which is syntactic sugar for {,D}LOG_IF(FATAL, assert fails) << assertion; +// +// There are "verbose level" logging macros. They look like +// +// VLOG(1) << "I'm printed when you run the program with --v=1 or more"; +// VLOG(2) << "I'm printed when you run the program with --v=2 or more"; +// +// These always log at the INFO log level (when they log at all). +// The verbose logging can also be turned on module-by-module. For instance, +// --vmodule=profile=2,icon_loader=1,browser_*=3,*/chromeos/*=4 --v=0 +// will cause: +// a. VLOG(2) and lower messages to be printed from profile.{h,cc} +// b. VLOG(1) and lower messages to be printed from icon_loader.{h,cc} +// c. VLOG(3) and lower messages to be printed from files prefixed with +// "browser" +// d. VLOG(4) and lower messages to be printed from files under a +// "chromeos" directory. +// e. VLOG(0) and lower messages to be printed from elsewhere +// +// The wildcarding functionality shown by (c) supports both '*' (match +// 0 or more characters) and '?' (match any single character) +// wildcards. Any pattern containing a forward or backward slash will +// be tested against the whole pathname and not just the module. +// E.g., "*/foo/bar/*=2" would change the logging level for all code +// in source files under a "foo/bar" directory. +// +// There's also VLOG_IS_ON(n) "verbose level" condition macro. To be used as +// +// if (VLOG_IS_ON(2)) { +// // do some logging preparation and logging +// // that can't be accomplished with just VLOG(2) << ...; +// } +// +// There is also a VLOG_IF "verbose level" condition macro for sample +// cases, when some extra computation and preparation for logs is not +// needed. +// +// VLOG_IF(1, (size > 1024)) +// << "I'm printed when size is more than 1024 and when you run the " +// "program with --v=1 or more"; +// +// We also override the standard 'assert' to use 'DLOG_ASSERT'. +// +// Lastly, there is: +// +// PLOG(ERROR) << "Couldn't do foo"; +// DPLOG(ERROR) << "Couldn't do foo"; +// PLOG_IF(ERROR, cond) << "Couldn't do foo"; +// DPLOG_IF(ERROR, cond) << "Couldn't do foo"; +// PCHECK(condition) << "Couldn't do foo"; +// DPCHECK(condition) << "Couldn't do foo"; +// +// which append the last system error to the message in string form (taken from +// GetLastError() on Windows and errno on POSIX). +// +// The supported severity levels for macros that allow you to specify one +// are (in increasing order of severity) INFO, WARNING, ERROR, ERROR_REPORT, +// and FATAL. +// +// Very important: logging a message at the FATAL severity level causes +// the program to terminate (after the message is logged). +// +// Note the special severity of ERROR_REPORT only available/relevant in normal +// mode, which displays error dialog without terminating the program. There is +// no error dialog for severity ERROR or below in normal mode. +// +// There is also the special severity of DFATAL, which logs FATAL in +// debug mode, ERROR in normal mode. + +namespace logging { + +// Where to record logging output? A flat file and/or system debug log via +// OutputDebugString. Defaults on Windows to LOG_ONLY_TO_FILE, and on +// POSIX to LOG_ONLY_TO_SYSTEM_DEBUG_LOG (aka stderr). +enum LoggingDestination { LOG_NONE, + LOG_ONLY_TO_FILE, + LOG_ONLY_TO_SYSTEM_DEBUG_LOG, + LOG_TO_BOTH_FILE_AND_SYSTEM_DEBUG_LOG }; + +// Indicates that the log file should be locked when being written to. +// Often, there is no locking, which is fine for a single threaded program. +// If logging is being done from multiple threads or there can be more than +// one process doing the logging, the file should be locked during writes to +// make each log outut atomic. Other writers will block. +// +// All processes writing to the log file must have their locking set for it to +// work properly. Defaults to DONT_LOCK_LOG_FILE. +enum LogLockingState { LOCK_LOG_FILE, DONT_LOCK_LOG_FILE }; + +// On startup, should we delete or append to an existing log file (if any)? +// Defaults to APPEND_TO_OLD_LOG_FILE. +enum OldFileDeletionState { DELETE_OLD_LOG_FILE, APPEND_TO_OLD_LOG_FILE }; + +enum DcheckState { + DISABLE_DCHECK_FOR_NON_OFFICIAL_RELEASE_BUILDS, + ENABLE_DCHECK_FOR_NON_OFFICIAL_RELEASE_BUILDS +}; + +// TODO(avi): do we want to do a unification of character types here? +#if defined(OS_WIN) +typedef wchar_t PathChar; +#else +typedef char PathChar; +#endif + +// Define different names for the BaseInitLoggingImpl() function depending on +// whether NDEBUG is defined or not so that we'll fail to link if someone tries +// to compile logging.cc with NDEBUG but includes logging.h without defining it, +// or vice versa. +#if NDEBUG +#define BaseInitLoggingImpl BaseInitLoggingImpl_built_with_NDEBUG +#else +#define BaseInitLoggingImpl BaseInitLoggingImpl_built_without_NDEBUG +#endif + +// Implementation of the InitLogging() method declared below. We use a +// more-specific name so we can #define it above without affecting other code +// that has named stuff "InitLogging". +BASE_EXPORT bool BaseInitLoggingImpl(const PathChar* log_file, + LoggingDestination logging_dest, + LogLockingState lock_log, + OldFileDeletionState delete_old, + DcheckState dcheck_state); + +// Sets the log file name and other global logging state. Calling this function +// is recommended, and is normally done at the beginning of application init. +// If you don't call it, all the flags will be initialized to their default +// values, and there is a race condition that may leak a critical section +// object if two threads try to do the first log at the same time. +// See the definition of the enums above for descriptions and default values. +// +// The default log file is initialized to "debug.log" in the application +// directory. You probably don't want this, especially since the program +// directory may not be writable on an enduser's system. +inline bool InitLogging(const PathChar* log_file, + LoggingDestination logging_dest, + LogLockingState lock_log, + OldFileDeletionState delete_old, + DcheckState dcheck_state) { + return BaseInitLoggingImpl(log_file, logging_dest, lock_log, + delete_old, dcheck_state); +} + +// Sets the log level. Anything at or above this level will be written to the +// log file/displayed to the user (if applicable). Anything below this level +// will be silently ignored. The log level defaults to 0 (everything is logged +// up to level INFO) if this function is not called. +// Note that log messages for VLOG(x) are logged at level -x, so setting +// the min log level to negative values enables verbose logging. +BASE_EXPORT void SetMinLogLevel(int level); + +// Gets the current log level. +BASE_EXPORT int GetMinLogLevel(); + +// Gets the VLOG default verbosity level. +BASE_EXPORT int GetVlogVerbosity(); + +// Gets the current vlog level for the given file (usually taken from +// __FILE__). + +// Note that |N| is the size *with* the null terminator. +BASE_EXPORT int GetVlogLevelHelper(const char* file_start, size_t N); + +template <size_t N> +int GetVlogLevel(const char (&file)[N]) { + return GetVlogLevelHelper(file, N); +} + +// Sets the common items you want to be prepended to each log message. +// process and thread IDs default to off, the timestamp defaults to on. +// If this function is not called, logging defaults to writing the timestamp +// only. +BASE_EXPORT void SetLogItems(bool enable_process_id, bool enable_thread_id, + bool enable_timestamp, bool enable_tickcount); + +// Sets whether or not you'd like to see fatal debug messages popped up in +// a dialog box or not. +// Dialogs are not shown by default. +BASE_EXPORT void SetShowErrorDialogs(bool enable_dialogs); + +// Sets the Log Assert Handler that will be used to notify of check failures. +// The default handler shows a dialog box and then terminate the process, +// however clients can use this function to override with their own handling +// (e.g. a silent one for Unit Tests) +typedef void (*LogAssertHandlerFunction)(const std::string& str); +BASE_EXPORT void SetLogAssertHandler(LogAssertHandlerFunction handler); + +// Sets the Log Report Handler that will be used to notify of check failures +// in non-debug mode. The default handler shows a dialog box and continues +// the execution, however clients can use this function to override with their +// own handling. +typedef void (*LogReportHandlerFunction)(const std::string& str); +BASE_EXPORT void SetLogReportHandler(LogReportHandlerFunction handler); + +// Sets the Log Message Handler that gets passed every log message before +// it's sent to other log destinations (if any). +// Returns true to signal that it handled the message and the message +// should not be sent to other log destinations. +typedef bool (*LogMessageHandlerFunction)(int severity, + const char* file, int line, size_t message_start, const std::string& str); +BASE_EXPORT void SetLogMessageHandler(LogMessageHandlerFunction handler); +BASE_EXPORT LogMessageHandlerFunction GetLogMessageHandler(); + +typedef int LogSeverity; +const LogSeverity LOG_VERBOSE = -1; // This is level 1 verbosity +// Note: the log severities are used to index into the array of names, +// see log_severity_names. +const LogSeverity LOG_INFO = 0; +const LogSeverity LOG_WARNING = 1; +const LogSeverity LOG_ERROR = 2; +const LogSeverity LOG_ERROR_REPORT = 3; +const LogSeverity LOG_FATAL = 4; +const LogSeverity LOG_NUM_SEVERITIES = 5; + +// LOG_DFATAL is LOG_FATAL in debug mode, ERROR in normal mode +#ifdef NDEBUG +const LogSeverity LOG_DFATAL = LOG_ERROR; +#else +const LogSeverity LOG_DFATAL = LOG_FATAL; +#endif + +// A few definitions of macros that don't generate much code. These are used +// by LOG() and LOG_IF, etc. Since these are used all over our code, it's +// better to have compact code for these operations. +#define COMPACT_GOOGLE_LOG_EX_INFO(ClassName, ...) \ + logging::ClassName(__FILE__, __LINE__, logging::LOG_INFO , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_EX_WARNING(ClassName, ...) \ + logging::ClassName(__FILE__, __LINE__, logging::LOG_WARNING , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_EX_ERROR(ClassName, ...) \ + logging::ClassName(__FILE__, __LINE__, logging::LOG_ERROR , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_EX_ERROR_REPORT(ClassName, ...) \ + logging::ClassName(__FILE__, __LINE__, \ + logging::LOG_ERROR_REPORT , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_EX_FATAL(ClassName, ...) \ + logging::ClassName(__FILE__, __LINE__, logging::LOG_FATAL , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_EX_DFATAL(ClassName, ...) \ + logging::ClassName(__FILE__, __LINE__, logging::LOG_DFATAL , ##__VA_ARGS__) + +#define COMPACT_GOOGLE_LOG_INFO \ + COMPACT_GOOGLE_LOG_EX_INFO(LogMessage) +#define COMPACT_GOOGLE_LOG_WARNING \ + COMPACT_GOOGLE_LOG_EX_WARNING(LogMessage) +#define COMPACT_GOOGLE_LOG_ERROR \ + COMPACT_GOOGLE_LOG_EX_ERROR(LogMessage) +#define COMPACT_GOOGLE_LOG_ERROR_REPORT \ + COMPACT_GOOGLE_LOG_EX_ERROR_REPORT(LogMessage) +#define COMPACT_GOOGLE_LOG_FATAL \ + COMPACT_GOOGLE_LOG_EX_FATAL(LogMessage) +#define COMPACT_GOOGLE_LOG_DFATAL \ + COMPACT_GOOGLE_LOG_EX_DFATAL(LogMessage) + +// wingdi.h defines ERROR to be 0. When we call LOG(ERROR), it gets +// substituted with 0, and it expands to COMPACT_GOOGLE_LOG_0. To allow us +// to keep using this syntax, we define this macro to do the same thing +// as COMPACT_GOOGLE_LOG_ERROR, and also define ERROR the same way that +// the Windows SDK does for consistency. +#define ERROR 0 +#define COMPACT_GOOGLE_LOG_EX_0(ClassName, ...) \ + COMPACT_GOOGLE_LOG_EX_ERROR(ClassName , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_0 COMPACT_GOOGLE_LOG_ERROR +// Needed for LOG_IS_ON(ERROR). +const LogSeverity LOG_0 = LOG_ERROR; + +// As special cases, we can assume that LOG_IS_ON(ERROR_REPORT) and +// LOG_IS_ON(FATAL) always hold. Also, LOG_IS_ON(DFATAL) always holds +// in debug mode. In particular, CHECK()s will always fire if they +// fail. +#define LOG_IS_ON(severity) \ + ((::logging::LOG_ ## severity) >= ::logging::GetMinLogLevel()) + +// We can't do any caching tricks with VLOG_IS_ON() like the +// google-glog version since it requires GCC extensions. This means +// that using the v-logging functions in conjunction with --vmodule +// may be slow. +#define VLOG_IS_ON(verboselevel) \ + ((verboselevel) <= ::logging::GetVlogLevel(__FILE__)) + +// Helper macro which avoids evaluating the arguments to a stream if +// the condition doesn't hold. +#define LAZY_STREAM(stream, condition) \ + !(condition) ? (void) 0 : ::logging::LogMessageVoidify() & (stream) + +// We use the preprocessor's merging operator, "##", so that, e.g., +// LOG(INFO) becomes the token COMPACT_GOOGLE_LOG_INFO. There's some funny +// subtle difference between ostream member streaming functions (e.g., +// ostream::operator<<(int) and ostream non-member streaming functions +// (e.g., ::operator<<(ostream&, string&): it turns out that it's +// impossible to stream something like a string directly to an unnamed +// ostream. We employ a neat hack by calling the stream() member +// function of LogMessage which seems to avoid the problem. +#define LOG_STREAM(severity) COMPACT_GOOGLE_LOG_ ## severity.stream() + +#define LOG(severity) LAZY_STREAM(LOG_STREAM(severity), LOG_IS_ON(severity)) +#define LOG_IF(severity, condition) \ + LAZY_STREAM(LOG_STREAM(severity), LOG_IS_ON(severity) && (condition)) + +#define SYSLOG(severity) LOG(severity) +#define SYSLOG_IF(severity, condition) LOG_IF(severity, condition) + +// The VLOG macros log with negative verbosities. +#define VLOG_STREAM(verbose_level) \ + logging::LogMessage(__FILE__, __LINE__, -verbose_level).stream() + +#define VLOG(verbose_level) \ + LAZY_STREAM(VLOG_STREAM(verbose_level), VLOG_IS_ON(verbose_level)) + +#define VLOG_IF(verbose_level, condition) \ + LAZY_STREAM(VLOG_STREAM(verbose_level), \ + VLOG_IS_ON(verbose_level) && (condition)) + +#if defined (OS_WIN) +#define VPLOG_STREAM(verbose_level) \ + logging::Win32ErrorLogMessage(__FILE__, __LINE__, -verbose_level, \ + ::logging::GetLastSystemErrorCode()).stream() +#elif defined(OS_POSIX) +#define VPLOG_STREAM(verbose_level) \ + logging::ErrnoLogMessage(__FILE__, __LINE__, -verbose_level, \ + ::logging::GetLastSystemErrorCode()).stream() +#endif + +#define VPLOG(verbose_level) \ + LAZY_STREAM(VPLOG_STREAM(verbose_level), VLOG_IS_ON(verbose_level)) + +#define VPLOG_IF(verbose_level, condition) \ + LAZY_STREAM(VPLOG_STREAM(verbose_level), \ + VLOG_IS_ON(verbose_level) && (condition)) + +// TODO(akalin): Add more VLOG variants, e.g. VPLOG. + +#define LOG_ASSERT(condition) \ + LOG_IF(FATAL, !(condition)) << "Assert failed: " #condition ". " +#define SYSLOG_ASSERT(condition) \ + SYSLOG_IF(FATAL, !(condition)) << "Assert failed: " #condition ". " + +#if defined(OS_WIN) +#define LOG_GETLASTERROR_STREAM(severity) \ + COMPACT_GOOGLE_LOG_EX_ ## severity(Win32ErrorLogMessage, \ + ::logging::GetLastSystemErrorCode()).stream() +#define LOG_GETLASTERROR(severity) \ + LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity), LOG_IS_ON(severity)) +#define LOG_GETLASTERROR_MODULE_STREAM(severity, module) \ + COMPACT_GOOGLE_LOG_EX_ ## severity(Win32ErrorLogMessage, \ + ::logging::GetLastSystemErrorCode(), module).stream() +#define LOG_GETLASTERROR_MODULE(severity, module) \ + LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity, module), \ + LOG_IS_ON(severity)) +// PLOG_STREAM is used by PLOG, which is the usual error logging macro +// for each platform. +#define PLOG_STREAM(severity) LOG_GETLASTERROR_STREAM(severity) +#elif defined(OS_POSIX) +#define LOG_ERRNO_STREAM(severity) \ + COMPACT_GOOGLE_LOG_EX_ ## severity(ErrnoLogMessage, \ + ::logging::GetLastSystemErrorCode()).stream() +#define LOG_ERRNO(severity) \ + LAZY_STREAM(LOG_ERRNO_STREAM(severity), LOG_IS_ON(severity)) +// PLOG_STREAM is used by PLOG, which is the usual error logging macro +// for each platform. +#define PLOG_STREAM(severity) LOG_ERRNO_STREAM(severity) +// TODO(tschmelcher): Should we add OSStatus logging for Mac? +#endif + +#define PLOG(severity) \ + LAZY_STREAM(PLOG_STREAM(severity), LOG_IS_ON(severity)) + +#define PLOG_IF(severity, condition) \ + LAZY_STREAM(PLOG_STREAM(severity), LOG_IS_ON(severity) && (condition)) + +// CHECK dies with a fatal error if condition is not true. It is *not* +// controlled by NDEBUG, so the check will be executed regardless of +// compilation mode. +// +// We make sure CHECK et al. always evaluates their arguments, as +// doing CHECK(FunctionWithSideEffect()) is a common idiom. +#define CHECK(condition) \ + LAZY_STREAM(LOG_STREAM(FATAL), !(condition)) \ + << "Check failed: " #condition ". " + +#define PCHECK(condition) \ + LAZY_STREAM(PLOG_STREAM(FATAL), !(condition)) \ + << "Check failed: " #condition ". " + +// Build the error message string. This is separate from the "Impl" +// function template because it is not performance critical and so can +// be out of line, while the "Impl" code should be inline. Caller +// takes ownership of the returned string. +template<class t1, class t2> +std::string* MakeCheckOpString(const t1& v1, const t2& v2, const char* names) { + std::ostringstream ss; + ss << names << " (" << v1 << " vs. " << v2 << ")"; + std::string* msg = new std::string(ss.str()); + return msg; +} + +// MSVC doesn't like complex extern templates and DLLs. +#if !defined(COMPILER_MSVC) && !defined(COMPONENT_BUILD) +// Commonly used instantiations of MakeCheckOpString<>. Explicitly instantiated +// in logging.cc. +extern template std::string* MakeCheckOpString<int, int>( + const int&, const int&, const char* names); +extern template std::string* MakeCheckOpString<unsigned long, unsigned long>( + const unsigned long&, const unsigned long&, const char* names); +extern template std::string* MakeCheckOpString<unsigned long, unsigned int>( + const unsigned long&, const unsigned int&, const char* names); +extern template std::string* MakeCheckOpString<unsigned int, unsigned long>( + const unsigned int&, const unsigned long&, const char* names); +extern template std::string* MakeCheckOpString<std::string, std::string>( + const std::string&, const std::string&, const char* name); +#endif + +// Helper macro for binary operators. +// Don't use this macro directly in your code, use CHECK_EQ et al below. +// +// TODO(akalin): Rewrite this so that constructs like if (...) +// CHECK_EQ(...) else { ... } work properly. +#define CHECK_OP(name, op, val1, val2) \ + if (std::string* _result = \ + logging::Check##name##Impl((val1), (val2), \ + #val1 " " #op " " #val2)) \ + logging::LogMessage(__FILE__, __LINE__, _result).stream() + +// Helper functions for CHECK_OP macro. +// The (int, int) specialization works around the issue that the compiler +// will not instantiate the template version of the function on values of +// unnamed enum type - see comment below. +#define DEFINE_CHECK_OP_IMPL(name, op) \ + template <class t1, class t2> \ + inline std::string* Check##name##Impl(const t1& v1, const t2& v2, \ + const char* names) { \ + if (v1 op v2) return NULL; \ + else return MakeCheckOpString(v1, v2, names); \ + } \ + inline std::string* Check##name##Impl(int v1, int v2, const char* names) { \ + if (v1 op v2) return NULL; \ + else return MakeCheckOpString(v1, v2, names); \ + } +DEFINE_CHECK_OP_IMPL(EQ, ==) +DEFINE_CHECK_OP_IMPL(NE, !=) +DEFINE_CHECK_OP_IMPL(LE, <=) +DEFINE_CHECK_OP_IMPL(LT, < ) +DEFINE_CHECK_OP_IMPL(GE, >=) +DEFINE_CHECK_OP_IMPL(GT, > ) +#undef DEFINE_CHECK_OP_IMPL + +#define CHECK_EQ(val1, val2) CHECK_OP(EQ, ==, val1, val2) +#define CHECK_NE(val1, val2) CHECK_OP(NE, !=, val1, val2) +#define CHECK_LE(val1, val2) CHECK_OP(LE, <=, val1, val2) +#define CHECK_LT(val1, val2) CHECK_OP(LT, < , val1, val2) +#define CHECK_GE(val1, val2) CHECK_OP(GE, >=, val1, val2) +#define CHECK_GT(val1, val2) CHECK_OP(GT, > , val1, val2) + +// http://crbug.com/16512 is open for a real fix for this. For now, Windows +// uses OFFICIAL_BUILD and other platforms use the branding flag when NDEBUG is +// defined. +#if ( defined(OS_WIN) && defined(OFFICIAL_BUILD)) || \ + (!defined(OS_WIN) && defined(NDEBUG) && defined(GOOGLE_CHROME_BUILD)) +// Used by unit tests. +#define LOGGING_IS_OFFICIAL_BUILD + +// In order to have optimized code for official builds, remove DLOGs and +// DCHECKs. +#define ENABLE_DLOG 0 +#define ENABLE_DCHECK 0 + +#elif defined(NDEBUG) +// Otherwise, if we're a release build, remove DLOGs but not DCHECKs +// (since those can still be turned on via a command-line flag). +#define ENABLE_DLOG 0 +#define ENABLE_DCHECK 1 + +#else +// Otherwise, we're a debug build so enable DLOGs and DCHECKs. +#define ENABLE_DLOG 1 +#define ENABLE_DCHECK 1 +#endif + +// Definitions for DLOG et al. + +#if ENABLE_DLOG + +#define DLOG_IS_ON(severity) LOG_IS_ON(severity) +#define DLOG_IF(severity, condition) LOG_IF(severity, condition) +#define DLOG_ASSERT(condition) LOG_ASSERT(condition) +#define DPLOG_IF(severity, condition) PLOG_IF(severity, condition) +#define DVLOG_IF(verboselevel, condition) VLOG_IF(verboselevel, condition) +#define DVPLOG_IF(verboselevel, condition) VPLOG_IF(verboselevel, condition) + +#else // ENABLE_DLOG + +// If ENABLE_DLOG is off, we want to avoid emitting any references to +// |condition| (which may reference a variable defined only if NDEBUG +// is not defined). Contrast this with DCHECK et al., which has +// different behavior. + +#define DLOG_EAT_STREAM_PARAMETERS \ + true ? (void) 0 : ::logging::LogMessageVoidify() & LOG_STREAM(FATAL) + +#define DLOG_IS_ON(severity) false +#define DLOG_IF(severity, condition) DLOG_EAT_STREAM_PARAMETERS +#define DLOG_ASSERT(condition) DLOG_EAT_STREAM_PARAMETERS +#define DPLOG_IF(severity, condition) DLOG_EAT_STREAM_PARAMETERS +#define DVLOG_IF(verboselevel, condition) DLOG_EAT_STREAM_PARAMETERS +#define DVPLOG_IF(verboselevel, condition) DLOG_EAT_STREAM_PARAMETERS + +#endif // ENABLE_DLOG + +// DEBUG_MODE is for uses like +// if (DEBUG_MODE) foo.CheckThatFoo(); +// instead of +// #ifndef NDEBUG +// foo.CheckThatFoo(); +// #endif +// +// We tie its state to ENABLE_DLOG. +enum { DEBUG_MODE = ENABLE_DLOG }; + +#undef ENABLE_DLOG + +#define DLOG(severity) \ + LAZY_STREAM(LOG_STREAM(severity), DLOG_IS_ON(severity)) + +#if defined(OS_WIN) +#define DLOG_GETLASTERROR(severity) \ + LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity), DLOG_IS_ON(severity)) +#define DLOG_GETLASTERROR_MODULE(severity, module) \ + LAZY_STREAM(LOG_GETLASTERROR_STREAM(severity, module), \ + DLOG_IS_ON(severity)) +#elif defined(OS_POSIX) +#define DLOG_ERRNO(severity) \ + LAZY_STREAM(LOG_ERRNO_STREAM(severity), DLOG_IS_ON(severity)) +#endif + +#define DPLOG(severity) \ + LAZY_STREAM(PLOG_STREAM(severity), DLOG_IS_ON(severity)) + +#define DVLOG(verboselevel) DLOG_IF(INFO, VLOG_IS_ON(verboselevel)) + +#define DVPLOG(verboselevel) DVPLOG_IF(verboselevel, VLOG_IS_ON(verboselevel)) + +// Definitions for DCHECK et al. + +#if ENABLE_DCHECK + +#if defined(NDEBUG) + +#define COMPACT_GOOGLE_LOG_EX_DCHECK(ClassName, ...) \ + COMPACT_GOOGLE_LOG_EX_ERROR_REPORT(ClassName , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_DCHECK COMPACT_GOOGLE_LOG_ERROR_REPORT +const LogSeverity LOG_DCHECK = LOG_ERROR_REPORT; +BASE_EXPORT extern DcheckState g_dcheck_state; +#define DCHECK_IS_ON() \ + ((::logging::g_dcheck_state == \ + ::logging::ENABLE_DCHECK_FOR_NON_OFFICIAL_RELEASE_BUILDS) && \ + LOG_IS_ON(DCHECK)) + +#else // defined(NDEBUG) + +// On a regular debug build, we want to have DCHECKs enabled. +#define COMPACT_GOOGLE_LOG_EX_DCHECK(ClassName, ...) \ + COMPACT_GOOGLE_LOG_EX_FATAL(ClassName , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_DCHECK COMPACT_GOOGLE_LOG_FATAL +const LogSeverity LOG_DCHECK = LOG_FATAL; +#define DCHECK_IS_ON() true + +#endif // defined(NDEBUG) + +#else // ENABLE_DCHECK + +// These are just dummy values since DCHECK_IS_ON() is always false in +// this case. +#define COMPACT_GOOGLE_LOG_EX_DCHECK(ClassName, ...) \ + COMPACT_GOOGLE_LOG_EX_INFO(ClassName , ##__VA_ARGS__) +#define COMPACT_GOOGLE_LOG_DCHECK COMPACT_GOOGLE_LOG_INFO +const LogSeverity LOG_DCHECK = LOG_INFO; +#define DCHECK_IS_ON() false + +#endif // ENABLE_DCHECK +#undef ENABLE_DCHECK + +// DCHECK et al. make sure to reference |condition| regardless of +// whether DCHECKs are enabled; this is so that we don't get unused +// variable warnings if the only use of a variable is in a DCHECK. +// This behavior is different from DLOG_IF et al. + +#define DCHECK(condition) \ + LAZY_STREAM(LOG_STREAM(DCHECK), DCHECK_IS_ON() && !(condition)) \ + << "Check failed: " #condition ". " + +#define DPCHECK(condition) \ + LAZY_STREAM(PLOG_STREAM(DCHECK), DCHECK_IS_ON() && !(condition)) \ + << "Check failed: " #condition ". " + +// Helper macro for binary operators. +// Don't use this macro directly in your code, use DCHECK_EQ et al below. +#define DCHECK_OP(name, op, val1, val2) \ + if (DCHECK_IS_ON()) \ + if (std::string* _result = \ + logging::Check##name##Impl((val1), (val2), \ + #val1 " " #op " " #val2)) \ + logging::LogMessage( \ + __FILE__, __LINE__, ::logging::LOG_DCHECK, \ + _result).stream() + +// Equality/Inequality checks - compare two values, and log a +// LOG_DCHECK message including the two values when the result is not +// as expected. The values must have operator<<(ostream, ...) +// defined. +// +// You may append to the error message like so: +// DCHECK_NE(1, 2) << ": The world must be ending!"; +// +// We are very careful to ensure that each argument is evaluated exactly +// once, and that anything which is legal to pass as a function argument is +// legal here. In particular, the arguments may be temporary expressions +// which will end up being destroyed at the end of the apparent statement, +// for example: +// DCHECK_EQ(string("abc")[1], 'b'); +// +// WARNING: These may not compile correctly if one of the arguments is a pointer +// and the other is NULL. To work around this, simply static_cast NULL to the +// type of the desired pointer. + +#define DCHECK_EQ(val1, val2) DCHECK_OP(EQ, ==, val1, val2) +#define DCHECK_NE(val1, val2) DCHECK_OP(NE, !=, val1, val2) +#define DCHECK_LE(val1, val2) DCHECK_OP(LE, <=, val1, val2) +#define DCHECK_LT(val1, val2) DCHECK_OP(LT, < , val1, val2) +#define DCHECK_GE(val1, val2) DCHECK_OP(GE, >=, val1, val2) +#define DCHECK_GT(val1, val2) DCHECK_OP(GT, > , val1, val2) + +#if defined(OS_ANDROID) && !defined(OFFICIAL_BUILD) +// TODO(port): fix once "enough" works +#define NOTREACHED() LOG(ERROR) << "NOTREACHED()" +#else +#define NOTREACHED() DCHECK(false) +#endif + +// Redefine the standard assert to use our nice log files +#undef assert +#define assert(x) DLOG_ASSERT(x) + +// This class more or less represents a particular log message. You +// create an instance of LogMessage and then stream stuff to it. +// When you finish streaming to it, ~LogMessage is called and the +// full message gets streamed to the appropriate destination. +// +// You shouldn't actually use LogMessage's constructor to log things, +// though. You should use the LOG() macro (and variants thereof) +// above. +class BASE_EXPORT LogMessage { + public: + LogMessage(const char* file, int line, LogSeverity severity, int ctr); + + // Two special constructors that generate reduced amounts of code at + // LOG call sites for common cases. + // + // Used for LOG(INFO): Implied are: + // severity = LOG_INFO, ctr = 0 + // + // Using this constructor instead of the more complex constructor above + // saves a couple of bytes per call site. + LogMessage(const char* file, int line); + + // Used for LOG(severity) where severity != INFO. Implied + // are: ctr = 0 + // + // Using this constructor instead of the more complex constructor above + // saves a couple of bytes per call site. + LogMessage(const char* file, int line, LogSeverity severity); + + // A special constructor used for check failures. Takes ownership + // of the given string. + // Implied severity = LOG_FATAL + LogMessage(const char* file, int line, std::string* result); + + // A special constructor used for check failures, with the option to + // specify severity. Takes ownership of the given string. + LogMessage(const char* file, int line, LogSeverity severity, + std::string* result); + + ~LogMessage(); + + std::ostream& stream() { return stream_; } + + private: + void Init(const char* file, int line); + + LogSeverity severity_; + std::ostringstream stream_; + size_t message_start_; // Offset of the start of the message (past prefix + // info). + // The file and line information passed in to the constructor. + const char* file_; + const int line_; + +#if defined(OS_WIN) + // Stores the current value of GetLastError in the constructor and restores + // it in the destructor by calling SetLastError. + // This is useful since the LogMessage class uses a lot of Win32 calls + // that will lose the value of GLE and the code that called the log function + // will have lost the thread error value when the log call returns. + class SaveLastError { + public: + SaveLastError(); + ~SaveLastError(); + + unsigned long get_error() const { return last_error_; } + + protected: + unsigned long last_error_; + }; + + SaveLastError last_error_; +#endif + + DISALLOW_COPY_AND_ASSIGN(LogMessage); +}; + +// A non-macro interface to the log facility; (useful +// when the logging level is not a compile-time constant). +inline void LogAtLevel(int const log_level, std::string const &msg) { + LogMessage(__FILE__, __LINE__, log_level).stream() << msg; +} + +// This class is used to explicitly ignore values in the conditional +// logging macros. This avoids compiler warnings like "value computed +// is not used" and "statement has no effect". +class LogMessageVoidify { + public: + LogMessageVoidify() { } + // This has to be an operator with a precedence lower than << but + // higher than ?: + void operator&(std::ostream&) { } +}; + +#if defined(OS_WIN) +typedef unsigned long SystemErrorCode; +#elif defined(OS_POSIX) +typedef int SystemErrorCode; +#endif + +// Alias for ::GetLastError() on Windows and errno on POSIX. Avoids having to +// pull in windows.h just for GetLastError() and DWORD. +BASE_EXPORT SystemErrorCode GetLastSystemErrorCode(); + +#if defined(OS_WIN) +// Appends a formatted system message of the GetLastError() type. +class BASE_EXPORT Win32ErrorLogMessage { + public: + Win32ErrorLogMessage(const char* file, + int line, + LogSeverity severity, + SystemErrorCode err, + const char* module); + + Win32ErrorLogMessage(const char* file, + int line, + LogSeverity severity, + SystemErrorCode err); + + // Appends the error message before destructing the encapsulated class. + ~Win32ErrorLogMessage(); + + std::ostream& stream() { return log_message_.stream(); } + + private: + SystemErrorCode err_; + // Optional name of the module defining the error. + const char* module_; + LogMessage log_message_; + + DISALLOW_COPY_AND_ASSIGN(Win32ErrorLogMessage); +}; +#elif defined(OS_POSIX) +// Appends a formatted system message of the errno type +class BASE_EXPORT ErrnoLogMessage { + public: + ErrnoLogMessage(const char* file, + int line, + LogSeverity severity, + SystemErrorCode err); + + // Appends the error message before destructing the encapsulated class. + ~ErrnoLogMessage(); + + std::ostream& stream() { return log_message_.stream(); } + + private: + SystemErrorCode err_; + LogMessage log_message_; + + DISALLOW_COPY_AND_ASSIGN(ErrnoLogMessage); +}; +#endif // OS_WIN + +// Closes the log file explicitly if open. +// NOTE: Since the log file is opened as necessary by the action of logging +// statements, there's no guarantee that it will stay closed +// after this call. +BASE_EXPORT void CloseLogFile(); + +// Async signal safe logging mechanism. +BASE_EXPORT void RawLog(int level, const char* message); + +#define RAW_LOG(level, message) logging::RawLog(logging::LOG_ ## level, message) + +#define RAW_CHECK(condition) \ + do { \ + if (!(condition)) \ + logging::RawLog(logging::LOG_FATAL, "Check failed: " #condition "\n"); \ + } while (0) + +} // namespace logging + +// These functions are provided as a convenience for logging, which is where we +// use streams (it is against Google style to use streams in other places). It +// is designed to allow you to emit non-ASCII Unicode strings to the log file, +// which is normally ASCII. It is relatively slow, so try not to use it for +// common cases. Non-ASCII characters will be converted to UTF-8 by these +// operators. +BASE_EXPORT std::ostream& operator<<(std::ostream& out, const wchar_t* wstr); +inline std::ostream& operator<<(std::ostream& out, const std::wstring& wstr) { + return out << wstr.c_str(); +} + +// The NOTIMPLEMENTED() macro annotates codepaths which have +// not been implemented yet. +// +// The implementation of this macro is controlled by NOTIMPLEMENTED_POLICY: +// 0 -- Do nothing (stripped by compiler) +// 1 -- Warn at compile time +// 2 -- Fail at compile time +// 3 -- Fail at runtime (DCHECK) +// 4 -- [default] LOG(ERROR) at runtime +// 5 -- LOG(ERROR) at runtime, only once per call-site + +#ifndef NOTIMPLEMENTED_POLICY +// Select default policy: LOG(ERROR) +#define NOTIMPLEMENTED_POLICY 4 +#endif + +#if defined(COMPILER_GCC) +// On Linux, with GCC, we can use __PRETTY_FUNCTION__ to get the demangled name +// of the current function in the NOTIMPLEMENTED message. +#define NOTIMPLEMENTED_MSG "Not implemented reached in " << __PRETTY_FUNCTION__ +#else +#define NOTIMPLEMENTED_MSG "NOT IMPLEMENTED" +#endif + +#if NOTIMPLEMENTED_POLICY == 0 +#define NOTIMPLEMENTED() ; +#elif NOTIMPLEMENTED_POLICY == 1 +// TODO, figure out how to generate a warning +#define NOTIMPLEMENTED() COMPILE_ASSERT(false, NOT_IMPLEMENTED) +#elif NOTIMPLEMENTED_POLICY == 2 +#define NOTIMPLEMENTED() COMPILE_ASSERT(false, NOT_IMPLEMENTED) +#elif NOTIMPLEMENTED_POLICY == 3 +#define NOTIMPLEMENTED() NOTREACHED() +#elif NOTIMPLEMENTED_POLICY == 4 +#define NOTIMPLEMENTED() LOG(ERROR) << NOTIMPLEMENTED_MSG +#elif NOTIMPLEMENTED_POLICY == 5 +#define NOTIMPLEMENTED() do {\ + static int count = 0;\ + LOG_IF(ERROR, 0 == count++) << NOTIMPLEMENTED_MSG;\ +} while(0) +#endif + +namespace base { + +class StringPiece; + +// Allows StringPiece to be logged. +BASE_EXPORT std::ostream& operator<<(std::ostream& o, const StringPiece& piece); + +} // namespace base + +#endif // BASE_LOGGING_H_ |