summaryrefslogtreecommitdiff
path: root/base/logging.h
diff options
context:
space:
mode:
Diffstat (limited to 'base/logging.h')
-rw-r--r--base/logging.h952
1 files changed, 952 insertions, 0 deletions
diff --git a/base/logging.h b/base/logging.h
new file mode 100644
index 0000000..c18fada
--- /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_