| // Copyright (c) 2012 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_ |
| |
| #include <stddef.h> |
| |
| #include <cassert> |
| #include <cstdint> |
| #include <cstring> |
| #include <sstream> |
| #include <string> |
| #include <type_traits> |
| #include <utility> |
| |
| #include "base/base_export.h" |
| #include "base/callback_forward.h" |
| #include "base/compiler_specific.h" |
| #include "base/immediate_crash.h" |
| #include "base/logging_buildflags.h" |
| #include "base/macros.h" |
| #include "base/scoped_clear_last_error.h" |
| #include "base/strings/string_piece_forward.h" |
| #include "base/template_util.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 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, and FATAL. |
| // |
| // Very important: logging a message at the FATAL severity level causes |
| // the program to terminate (after the message is logged). |
| // |
| // There is the special severity of DFATAL, which logs FATAL in debug mode, |
| // ERROR in normal mode. |
| // |
| // Output is of the format, for example: |
| // [3816:3877:0812/234555.406952:VERBOSE1:drm_device_handle.cc(90)] Succeeded |
| // authenticating /dev/dri/card0 in 0 ms with 1 attempt(s) |
| // |
| // The colon separated fields inside the brackets are as follows: |
| // 0. An optional Logfile prefix (not included in this example) |
| // 1. Process ID |
| // 2. Thread ID |
| // 3. The date/time of the log message, in MMDD/HHMMSS.Milliseconds format |
| // 4. The log level |
| // 5. The filename and line number where the log was instantiated |
| // |
| // Note that the visibility can be changed by setting preferences in |
| // SetLogItems() |
| |
| namespace logging { |
| |
| // TODO(avi): do we want to do a unification of character types here? |
| #if defined(OS_WIN) |
| typedef base::char16 PathChar; |
| #elif defined(OS_POSIX) || defined(OS_FUCHSIA) |
| typedef char PathChar; |
| #endif |
| |
| // A bitmask of potential logging destinations. |
| using LoggingDestination = uint32_t; |
| // Specifies where logs will be written. Multiple destinations can be specified |
| // with bitwise OR. |
| // Unless destination is LOG_NONE, all logs with severity ERROR and above will |
| // be written to stderr in addition to the specified destination. |
| enum : uint32_t { |
| LOG_NONE = 0, |
| LOG_TO_FILE = 1 << 0, |
| LOG_TO_SYSTEM_DEBUG_LOG = 1 << 1, |
| LOG_TO_STDERR = 1 << 2, |
| |
| LOG_TO_ALL = LOG_TO_FILE | LOG_TO_SYSTEM_DEBUG_LOG | LOG_TO_STDERR, |
| |
| // On Windows, use a file next to the exe. |
| // On POSIX platforms, where it may not even be possible to locate the |
| // executable on disk, use stderr. |
| // On Fuchsia, use the Fuchsia logging service. |
| #if defined(OS_FUCHSIA) || defined(OS_NACL) |
| LOG_DEFAULT = LOG_TO_SYSTEM_DEBUG_LOG, |
| #elif defined(OS_WIN) |
| LOG_DEFAULT = LOG_TO_FILE, |
| #elif defined(OS_POSIX) |
| LOG_DEFAULT = LOG_TO_SYSTEM_DEBUG_LOG | LOG_TO_STDERR, |
| #endif |
| }; |
| |
| // Indicates that the log file should be locked when being written to. |
| // Unless there is only one single-threaded process that is logging to |
| // the log file, the file should be locked during writes to make each |
| // log output atomic. Other writers will block. |
| // |
| // All processes writing to the log file must have their locking set for it to |
| // work properly. Defaults to 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 }; |
| |
| struct BASE_EXPORT LoggingSettings { |
| // Equivalent to logging destination enum, but allows for multiple |
| // destinations. |
| uint32_t logging_dest = LOG_DEFAULT; |
| |
| // The three settings below have an effect only when LOG_TO_FILE is |
| // set in |logging_dest|. |
| const PathChar* log_file = nullptr; |
| LogLockingState lock_log = LOCK_LOG_FILE; |
| OldFileDeletionState delete_old = APPEND_TO_OLD_LOG_FILE; |
| }; |
| |
| // 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 defined(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 LoggingSettings& settings); |
| |
| // 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. |
| // |
| // This function may be called a second time to re-direct logging (e.g after |
| // loging in to a user partition), however it should never be called more than |
| // twice. |
| inline bool InitLogging(const LoggingSettings& settings) { |
| return BaseInitLoggingImpl(settings); |
| } |
| |
| // 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(); |
| |
| // Used by LOG_IS_ON to lazy-evaluate stream arguments. |
| BASE_EXPORT bool ShouldCreateLogMessage(int severity); |
| |
| // Gets the VLOG default verbosity level. |
| BASE_EXPORT int GetVlogVerbosity(); |
| |
| // Note that |N| is the size *with* the null terminator. |
| BASE_EXPORT int GetVlogLevelHelper(const char* file_start, size_t N); |
| |
| // Gets the current vlog level for the given file (usually taken from __FILE__). |
| 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 an optional prefix to add to each log message. |prefix| is not copied |
| // and should be a raw string constant. |prefix| must only contain ASCII letters |
| // to avoid confusion with PIDs and timestamps. Pass null to remove the prefix. |
| // Logging defaults to no prefix. |
| BASE_EXPORT void SetLogPrefix(const char* prefix); |
| |
| // 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. |
| // Resets Log Assert Handler on object destruction. |
| // 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) |
| using LogAssertHandlerFunction = |
| base::RepeatingCallback<void(const char* file, |
| int line, |
| const base::StringPiece message, |
| const base::StringPiece stack_trace)>; |
| |
| class BASE_EXPORT ScopedLogAssertHandler { |
| public: |
| explicit ScopedLogAssertHandler(LogAssertHandlerFunction handler); |
| ~ScopedLogAssertHandler(); |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(ScopedLogAssertHandler); |
| }; |
| |
| // 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(); |
| |
| // The ANALYZER_ASSUME_TRUE(bool arg) macro adds compiler-specific hints |
| // to Clang which control what code paths are statically analyzed, |
| // and is meant to be used in conjunction with assert & assert-like functions. |
| // The expression is passed straight through if analysis isn't enabled. |
| // |
| // ANALYZER_SKIP_THIS_PATH() suppresses static analysis for the current |
| // codepath and any other branching codepaths that might follow. |
| #if defined(__clang_analyzer__) |
| |
| inline constexpr bool AnalyzerNoReturn() __attribute__((analyzer_noreturn)) { |
| return false; |
| } |
| |
| inline constexpr bool AnalyzerAssumeTrue(bool arg) { |
| // AnalyzerNoReturn() is invoked and analysis is terminated if |arg| is |
| // false. |
| return arg || AnalyzerNoReturn(); |
| } |
| |
| #define ANALYZER_ASSUME_TRUE(arg) logging::AnalyzerAssumeTrue(!!(arg)) |
| #define ANALYZER_SKIP_THIS_PATH() \ |
| static_cast<void>(::logging::AnalyzerNoReturn()) |
| #define ANALYZER_ALLOW_UNUSED(var) static_cast<void>(var); |
| |
| #else // !defined(__clang_analyzer__) |
| |
| #define ANALYZER_ASSUME_TRUE(arg) (arg) |
| #define ANALYZER_SKIP_THIS_PATH() |
| #define ANALYZER_ALLOW_UNUSED(var) static_cast<void>(var); |
| |
| #endif // defined(__clang_analyzer__) |
| |
| 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_FATAL = 3; |
| const LogSeverity LOG_NUM_SEVERITIES = 4; |
| |
| // LOG_DFATAL is LOG_FATAL in debug mode, ERROR in normal mode |
| #if defined(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_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_EX_DCHECK(ClassName, ...) \ |
| ::logging::ClassName(__FILE__, __LINE__, ::logging::LOG_DCHECK, ##__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_FATAL COMPACT_GOOGLE_LOG_EX_FATAL(LogMessage) |
| #define COMPACT_GOOGLE_LOG_DFATAL COMPACT_GOOGLE_LOG_EX_DFATAL(LogMessage) |
| #define COMPACT_GOOGLE_LOG_DCHECK COMPACT_GOOGLE_LOG_EX_DCHECK(LogMessage) |
| |
| #if defined(OS_WIN) |
| // 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; |
| #endif |
| |
| // As special cases, we can assume that LOG_IS_ON(FATAL) always holds. 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::ShouldCreateLogMessage(::logging::LOG_##severity)) |
| |
| // We don't do any caching tricks with VLOG_IS_ON() like the |
| // google-glog version since it increases binary size. 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. Condition is evaluated once and only once. |
| #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)) |
| |
| // 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) || defined(OS_FUCHSIA) |
| #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, !(ANALYZER_ASSUME_TRUE(condition))) \ |
| << "Assert failed: " #condition ". " |
| |
| #if defined(OS_WIN) |
| #define PLOG_STREAM(severity) \ |
| COMPACT_GOOGLE_LOG_EX_ ## severity(Win32ErrorLogMessage, \ |
| ::logging::GetLastSystemErrorCode()).stream() |
| #elif defined(OS_POSIX) || defined(OS_FUCHSIA) |
| #define PLOG_STREAM(severity) \ |
| COMPACT_GOOGLE_LOG_EX_ ## severity(ErrnoLogMessage, \ |
| ::logging::GetLastSystemErrorCode()).stream() |
| #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)) |
| |
| BASE_EXPORT extern std::ostream* g_swallow_stream; |
| |
| // Note that g_swallow_stream is used instead of an arbitrary LOG() stream to |
| // avoid the creation of an object with a non-trivial destructor (LogMessage). |
| // On MSVC x86 (checked on 2015 Update 3), this causes a few additional |
| // pointless instructions to be emitted even at full optimization level, even |
| // though the : arm of the ternary operator is clearly never executed. Using a |
| // simpler object to be &'d with Voidify() avoids these extra instructions. |
| // Using a simpler POD object with a templated operator<< also works to avoid |
| // these instructions. However, this causes warnings on statically defined |
| // implementations of operator<<(std::ostream, ...) in some .cc files, because |
| // they become defined-but-unreferenced functions. A reinterpret_cast of 0 to an |
| // ostream* also is not suitable, because some compilers warn of undefined |
| // behavior. |
| #define EAT_STREAM_PARAMETERS \ |
| true ? (void)0 \ |
| : ::logging::LogMessageVoidify() & (*::logging::g_swallow_stream) |
| |
| // Captures the result of a CHECK_EQ (for example) and facilitates testing as a |
| // boolean. |
| class CheckOpResult { |
| public: |
| // |message| must be non-null if and only if the check failed. |
| CheckOpResult(std::string* message) : message_(message) {} |
| // Returns true if the check succeeded. |
| operator bool() const { return !message_; } |
| // Returns the message. |
| std::string* message() { return message_; } |
| |
| private: |
| std::string* message_; |
| }; |
| |
| // 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. |
| |
| #if defined(OFFICIAL_BUILD) && defined(NDEBUG) |
| |
| // Make all CHECK functions discard their log strings to reduce code bloat, and |
| // improve performance, for official release builds. |
| // |
| // This is not calling BreakDebugger since this is called frequently, and |
| // calling an out-of-line function instead of a noreturn inline macro prevents |
| // compiler optimizations. |
| #define CHECK(condition) \ |
| UNLIKELY(!(condition)) ? IMMEDIATE_CRASH() : EAT_STREAM_PARAMETERS |
| |
| // PCHECK includes the system error code, which is useful for determining |
| // why the condition failed. In official builds, preserve only the error code |
| // message so that it is available in crash reports. The stringified |
| // condition and any additional stream parameters are dropped. |
| #define PCHECK(condition) \ |
| LAZY_STREAM(PLOG_STREAM(FATAL), UNLIKELY(!(condition))); \ |
| EAT_STREAM_PARAMETERS |
| |
| #define CHECK_OP(name, op, val1, val2) CHECK((val1) op (val2)) |
| |
| #else // !(OFFICIAL_BUILD && NDEBUG) |
| |
| // Do as much work as possible out of line to reduce inline code size. |
| #define CHECK(condition) \ |
| LAZY_STREAM(::logging::LogMessage(__FILE__, __LINE__, #condition).stream(), \ |
| !ANALYZER_ASSUME_TRUE(condition)) |
| |
| #define PCHECK(condition) \ |
| LAZY_STREAM(PLOG_STREAM(FATAL), !ANALYZER_ASSUME_TRUE(condition)) \ |
| << "Check failed: " #condition ". " |
| |
| // Helper macro for binary operators. |
| // Don't use this macro directly in your code, use CHECK_EQ et al below. |
| // The 'switch' is used to prevent the 'else' from being ambiguous when the |
| // macro is used in an 'if' clause such as: |
| // if (a == 1) |
| // CHECK_EQ(2, a); |
| #define CHECK_OP(name, op, val1, val2) \ |
| switch (0) case 0: default: \ |
| if (::logging::CheckOpResult true_if_passed = \ |
| ::logging::Check##name##Impl((val1), (val2), \ |
| #val1 " " #op " " #val2)) \ |
| ; \ |
| else \ |
| ::logging::LogMessage(__FILE__, __LINE__, true_if_passed.message()).stream() |
| |
| #endif // !(OFFICIAL_BUILD && NDEBUG) |
| |
| // This formats a value for a failing CHECK_XX statement. Ordinarily, |
| // it uses the definition for operator<<, with a few special cases below. |
| template <typename T> |
| inline typename std::enable_if< |
| base::internal::SupportsOstreamOperator<const T&>::value && |
| !std::is_function<typename std::remove_pointer<T>::type>::value, |
| void>::type |
| MakeCheckOpValueString(std::ostream* os, const T& v) { |
| (*os) << v; |
| } |
| |
| // Overload for types that no operator<< but do have .ToString() defined. |
| template <typename T> |
| inline typename std::enable_if< |
| !base::internal::SupportsOstreamOperator<const T&>::value && |
| base::internal::SupportsToString<const T&>::value, |
| void>::type |
| MakeCheckOpValueString(std::ostream* os, const T& v) { |
| (*os) << v.ToString(); |
| } |
| |
| // Provide an overload for functions and function pointers. Function pointers |
| // don't implicitly convert to void* but do implicitly convert to bool, so |
| // without this function pointers are always printed as 1 or 0. (MSVC isn't |
| // standards-conforming here and converts function pointers to regular |
| // pointers, so this is a no-op for MSVC.) |
| template <typename T> |
| inline typename std::enable_if< |
| std::is_function<typename std::remove_pointer<T>::type>::value, |
| void>::type |
| MakeCheckOpValueString(std::ostream* os, const T& v) { |
| (*os) << reinterpret_cast<const void*>(v); |
| } |
| |
| // We need overloads for enums that don't support operator<<. |
| // (i.e. scoped enums where no operator<< overload was declared). |
| template <typename T> |
| inline typename std::enable_if< |
| !base::internal::SupportsOstreamOperator<const T&>::value && |
| std::is_enum<T>::value, |
| void>::type |
| MakeCheckOpValueString(std::ostream* os, const T& v) { |
| (*os) << static_cast<typename std::underlying_type<T>::type>(v); |
| } |
| |
| // We need an explicit overload for std::nullptr_t. |
| BASE_EXPORT void MakeCheckOpValueString(std::ostream* os, std::nullptr_t p); |
| |
| // 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 << " ("; |
| MakeCheckOpValueString(&ss, v1); |
| ss << " vs. "; |
| MakeCheckOpValueString(&ss, v2); |
| ss << ")"; |
| std::string* msg = new std::string(ss.str()); |
| return msg; |
| } |
| |
| // Commonly used instantiations of MakeCheckOpString<>. Explicitly instantiated |
| // in logging.cc. |
| extern template BASE_EXPORT std::string* MakeCheckOpString<int, int>( |
| const int&, const int&, const char* names); |
| extern template BASE_EXPORT |
| std::string* MakeCheckOpString<unsigned long, unsigned long>( |
| const unsigned long&, const unsigned long&, const char* names); |
| extern template BASE_EXPORT |
| std::string* MakeCheckOpString<unsigned long, unsigned int>( |
| const unsigned long&, const unsigned int&, const char* names); |
| extern template BASE_EXPORT |
| std::string* MakeCheckOpString<unsigned int, unsigned long>( |
| const unsigned int&, const unsigned long&, const char* names); |
| extern template BASE_EXPORT |
| std::string* MakeCheckOpString<std::string, std::string>( |
| const std::string&, const std::string&, const char* name); |
| |
| // 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. |
| // |
| // The checked condition is wrapped with ANALYZER_ASSUME_TRUE, which under |
| // static analysis builds, blocks analysis of the current path if the |
| // condition is false. |
| #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 (ANALYZER_ASSUME_TRUE(v1 op v2)) \ |
| return NULL; \ |
| else \ |
| return ::logging::MakeCheckOpString(v1, v2, names); \ |
| } \ |
| inline std::string* Check##name##Impl(int v1, int v2, const char* names) { \ |
| if (ANALYZER_ASSUME_TRUE(v1 op v2)) \ |
| return NULL; \ |
| else \ |
| return ::logging::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) |
| |
| #if defined(NDEBUG) && !defined(DCHECK_ALWAYS_ON) |
| #define DCHECK_IS_ON() 0 |
| #else |
| #define DCHECK_IS_ON() 1 |
| #endif |
| |
| // Definitions for DLOG et al. |
| |
| #if DCHECK_IS_ON() |
| |
| #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 // DCHECK_IS_ON() |
| |
| // If !DCHECK_IS_ON(), we want to avoid emitting any references to |condition| |
| // (which may reference a variable defined only if DCHECK_IS_ON()). |
| // Contrast this with DCHECK et al., which has different behavior. |
| |
| #define DLOG_IS_ON(severity) false |
| #define DLOG_IF(severity, condition) EAT_STREAM_PARAMETERS |
| #define DLOG_ASSERT(condition) EAT_STREAM_PARAMETERS |
| #define DPLOG_IF(severity, condition) EAT_STREAM_PARAMETERS |
| #define DVLOG_IF(verboselevel, condition) EAT_STREAM_PARAMETERS |
| #define DVPLOG_IF(verboselevel, condition) EAT_STREAM_PARAMETERS |
| |
| #endif // DCHECK_IS_ON() |
| |
| #define DLOG(severity) \ |
| LAZY_STREAM(LOG_STREAM(severity), DLOG_IS_ON(severity)) |
| |
| #define DPLOG(severity) \ |
| LAZY_STREAM(PLOG_STREAM(severity), DLOG_IS_ON(severity)) |
| |
| #define DVLOG(verboselevel) DVLOG_IF(verboselevel, true) |
| |
| #define DVPLOG(verboselevel) DVPLOG_IF(verboselevel, true) |
| |
| // Definitions for DCHECK et al. |
| |
| #if DCHECK_IS_ON() |
| |
| #if defined(DCHECK_IS_CONFIGURABLE) |
| BASE_EXPORT extern LogSeverity LOG_DCHECK; |
| #else |
| const LogSeverity LOG_DCHECK = LOG_FATAL; |
| #endif // defined(DCHECK_IS_CONFIGURABLE) |
| |
| #else // DCHECK_IS_ON() |
| |
| // There may be users of LOG_DCHECK that are enabled independently |
| // of DCHECK_IS_ON(), so default to FATAL logging for those. |
| const LogSeverity LOG_DCHECK = LOG_FATAL; |
| |
| #endif // DCHECK_IS_ON() |
| |
| // 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. |
| // |
| // Note that the definition of the DCHECK macros depends on whether or not |
| // DCHECK_IS_ON() is true. When DCHECK_IS_ON() is false, the macros use |
| // EAT_STREAM_PARAMETERS to avoid expressions that would create temporaries. |
| |
| #if DCHECK_IS_ON() |
| |
| #define DCHECK(condition) \ |
| LAZY_STREAM(LOG_STREAM(DCHECK), !ANALYZER_ASSUME_TRUE(condition)) \ |
| << "Check failed: " #condition ". " |
| #define DPCHECK(condition) \ |
| LAZY_STREAM(PLOG_STREAM(DCHECK), !ANALYZER_ASSUME_TRUE(condition)) \ |
| << "Check failed: " #condition ". " |
| |
| #else // DCHECK_IS_ON() |
| |
| #define DCHECK(condition) EAT_STREAM_PARAMETERS << !(condition) |
| #define DPCHECK(condition) EAT_STREAM_PARAMETERS << !(condition) |
| |
| #endif // DCHECK_IS_ON() |
| |
| // Helper macro for binary operators. |
| // Don't use this macro directly in your code, use DCHECK_EQ et al below. |
| // The 'switch' is used to prevent the 'else' from being ambiguous when the |
| // macro is used in an 'if' clause such as: |
| // if (a == 1) |
| // DCHECK_EQ(2, a); |
| #if DCHECK_IS_ON() |
| |
| #define DCHECK_OP(name, op, val1, val2) \ |
| switch (0) case 0: default: \ |
| if (::logging::CheckOpResult true_if_passed = \ |
| ::logging::Check##name##Impl((val1), (val2), \ |
| #val1 " " #op " " #val2)) \ |
| ; \ |
| else \ |
| ::logging::LogMessage(__FILE__, __LINE__, ::logging::LOG_DCHECK, \ |
| true_if_passed.message()).stream() |
| |
| #else // DCHECK_IS_ON() |
| |
| // When DCHECKs aren't enabled, DCHECK_OP still needs to reference operator<< |
| // overloads for |val1| and |val2| to avoid potential compiler warnings about |
| // unused functions. For the same reason, it also compares |val1| and |val2| |
| // using |op|. |
| // |
| // Note that the contract of DCHECK_EQ, etc is that arguments are only evaluated |
| // once. Even though |val1| and |val2| appear twice in this version of the macro |
| // expansion, this is OK, since the expression is never actually evaluated. |
| #define DCHECK_OP(name, op, val1, val2) \ |
| EAT_STREAM_PARAMETERS << (::logging::MakeCheckOpValueString( \ |
| ::logging::g_swallow_stream, val1), \ |
| ::logging::MakeCheckOpValueString( \ |
| ::logging::g_swallow_stream, val2), \ |
| (val1)op(val2)) |
| |
| #endif // DCHECK_IS_ON() |
| |
| // 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 don't compile correctly if one of the arguments is a pointer |
| // and the other is NULL. In new code, prefer nullptr instead. To |
| // work around this for C++98, 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 BUILDFLAG(ENABLE_LOG_ERROR_NOT_REACHED) |
| // Implement logging of NOTREACHED() as a dedicated function to get function |
| // call overhead down to a minimum. |
| void LogErrorNotReached(const char* file, int line); |
| #define NOTREACHED() \ |
| true ? ::logging::LogErrorNotReached(__FILE__, __LINE__) \ |
| : EAT_STREAM_PARAMETERS |
| #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: |
| // Used for LOG(severity). |
| LogMessage(const char* file, int line, LogSeverity severity); |
| |
| // Used for CHECK(). Implied severity = LOG_FATAL. |
| LogMessage(const char* file, int line, const char* condition); |
| |
| // Used for CHECK_EQ(), etc. Takes ownership of the given string. |
| // Implied severity = LOG_FATAL. |
| LogMessage(const char* file, int line, std::string* result); |
| |
| // Used for DCHECK_EQ(), etc. Takes ownership of the given string. |
| LogMessage(const char* file, int line, LogSeverity severity, |
| std::string* result); |
| |
| ~LogMessage(); |
| |
| std::ostream& stream() { return stream_; } |
| |
| LogSeverity severity() { return severity_; } |
| std::string str() { return stream_.str(); } |
| |
| 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_; |
| |
| // 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. |
| base::internal::ScopedClearLastError last_error_; |
| |
| DISALLOW_COPY_AND_ASSIGN(LogMessage); |
| }; |
| |
| // 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() = default; |
| // 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) || defined(OS_FUCHSIA) |
| 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(); |
| BASE_EXPORT std::string SystemErrorCodeToString(SystemErrorCode error_code); |
| |
| #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); |
| |
| // Appends the error message before destructing the encapsulated class. |
| ~Win32ErrorLogMessage(); |
| |
| std::ostream& stream() { return log_message_.stream(); } |
| |
| private: |
| SystemErrorCode err_; |
| LogMessage log_message_; |
| |
| DISALLOW_COPY_AND_ASSIGN(Win32ErrorLogMessage); |
| }; |
| #elif defined(OS_POSIX) || defined(OS_FUCHSIA) |
| // 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) |
| |
| #if defined(OS_WIN) |
| // Returns true if logging to file is enabled. |
| BASE_EXPORT bool IsLoggingToFileEnabled(); |
| |
| // Returns the default log file path. |
| BASE_EXPORT base::string16 GetLogFileFullPath(); |
| #endif |
| |
| } // namespace logging |
| |
| // Note that "The behavior of a C++ program is undefined if it adds declarations |
| // or definitions to namespace std or to a namespace within namespace std unless |
| // otherwise specified." --C++11[namespace.std] |
| // |
| // We've checked that this particular definition has the intended behavior on |
| // our implementations, but it's prone to breaking in the future, and please |
| // don't imitate this in your own definitions without checking with some |
| // standard library experts. |
| namespace std { |
| // 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(); |
| } |
| } // namespace std |
| |
| // The NOTIMPLEMENTED() macro annotates codepaths which have not been |
| // implemented yet. If output spam is a serious concern, |
| // NOTIMPLEMENTED_LOG_ONCE can be used. |
| |
| #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 |
| |
| #define NOTIMPLEMENTED() DLOG(ERROR) << NOTIMPLEMENTED_MSG |
| #define NOTIMPLEMENTED_LOG_ONCE() \ |
| do { \ |
| static bool logged_once = false; \ |
| DLOG_IF(ERROR, !logged_once) << NOTIMPLEMENTED_MSG; \ |
| logged_once = true; \ |
| } while (0); \ |
| EAT_STREAM_PARAMETERS |
| |
| #endif // BASE_LOGGING_H_ |