// Copyright (c) 2022, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Author: Ray Sidney
//
// This file contains #include information about logging-related stuff.
// Pretty much everybody needs to #include this file so that they can
// log various happenings.
//
#ifndef GLOG_LOGGING_H
#define GLOG_LOGGING_H

#if 1 && __cplusplus >= 201103L
#include <chrono>
#endif

#include <cerrno>
#include <cstddef>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iosfwd>
#include <ostream>
#include <sstream>
#include <string>
#if 0
#include <unistd.h>
#endif
#include <vector>

#if defined(_MSC_VER)
#define GLOG_MSVC_PUSH_DISABLE_WARNING(n) __pragma(warning(push)) \
    __pragma(warning(disable                                      \
                     : n))
#define GLOG_MSVC_POP_WARNING() __pragma(warning(pop))
#else
#define GLOG_MSVC_PUSH_DISABLE_WARNING(n)
#define GLOG_MSVC_POP_WARNING()
#endif

#include <glog/platform.h>

#if 1
#include <glog/export.h>
#endif

// We care a lot about number of bits things take up.  Unfortunately,
// systems define their bit-specific ints in a lot of different ways.
// We use our own way, and have a typedef to get there.
// Note: these commands below may look like "#if 1" or "#if 0", but
// that's because they were constructed that way at ./configure time.
// Look at logging.h.in to see how they're calculated (based on your config).
#if 1
#include <stdint.h> // the normal place uint16_t is defined
#endif
#if 1
#include <sys/types.h> // the normal place u_int16_t is defined
#endif
#if 1
#include <inttypes.h> // a third place for uint16_t or u_int16_t
#endif

#if 0
#include <gflags/gflags.h>
#endif

#if 1 && __cplusplus >= 201103L
#include <atomic>
#elif defined(GLOG_OS_WINDOWS)
#include <Windows.h>
#endif

namespace google
{

#if 1 // the C99 format
    typedef int32_t int32;
    typedef uint32_t uint32;
    typedef int64_t int64;
    typedef uint64_t uint64;
#elif 0 // the BSD format
    typedef int32_t int32;
    typedef u_int32_t uint32;
    typedef int64_t int64;
    typedef u_int64_t uint64;
#elif 1 // the windows (vc7) format
    typedef __int32 int32;
    typedef unsigned __int32 uint32;
    typedef __int64 int64;
    typedef unsigned __int64 uint64;
#else
#error Do not know how to define a 32-bit integer quantity on your system
#endif

#if !(0)
    typedef ptrdiff_t ssize_t;
#endif

#if !(0)
    typedef int mode_t;
#endif

    typedef double WallTime;

    struct GLOG_EXPORT LogMessageTime
    {
        LogMessageTime();
        LogMessageTime(std::tm t);
        LogMessageTime(std::time_t timestamp, WallTime now);

        const time_t &timestamp() const { return timestamp_; }
        const int &sec() const { return time_struct_.tm_sec; }
        const int32_t &usec() const { return usecs_; }
        const int &(min)() const { return time_struct_.tm_min; }
        const int &hour() const { return time_struct_.tm_hour; }
        const int &day() const { return time_struct_.tm_mday; }
        const int &month() const { return time_struct_.tm_mon; }
        const int &year() const { return time_struct_.tm_year; }
        const int &dayOfWeek() const { return time_struct_.tm_wday; }
        const int &dayInYear() const { return time_struct_.tm_yday; }
        const int &dst() const { return time_struct_.tm_isdst; }
        const long int &gmtoff() const { return gmtoffset_; }
        const std::tm &tm() const { return time_struct_; }

    private:
        void init(const std::tm &t, std::time_t timestamp, WallTime now);
        std::tm time_struct_; // Time of creation of LogMessage
        time_t timestamp_;    // Time of creation of LogMessage in seconds
        int32_t usecs_;       // Time of creation of LogMessage - microseconds part
        long int gmtoffset_;

        void CalcGmtOffset();
    };

#ifdef GLOG_CUSTOM_PREFIX_SUPPORT
    struct LogMessageInfo
    {
        explicit LogMessageInfo(const char *const severity_,
                                const char *const filename_,
                                const int &line_number_,
                                const int &thread_id_,
                                const LogMessageTime &time_) : severity(severity_), filename(filename_), line_number(line_number_),
                                                               thread_id(thread_id_), time(time_)
        {
        }

        const char *const severity;
        const char *const filename;
        const int &line_number;
        const int &thread_id;
        const LogMessageTime &time;
    };

    typedef void (*CustomPrefixCallback)(std::ostream &s, const LogMessageInfo &l, void *data);

#endif

}

// The global value of GOOGLE_STRIP_LOG. All the messages logged to
// LOG(XXX) with severity less than GOOGLE_STRIP_LOG will not be displayed.
// If it can be determined at compile time that the message will not be
// printed, the statement will be compiled out.
//
// Example: to strip out all INFO and WARNING messages, use the value
// of 2 below. To make an exception for WARNING messages from a single
// file, add "#define GOOGLE_STRIP_LOG 1" to that file _before_ including
// base/logging.h
#ifndef GOOGLE_STRIP_LOG
#define GOOGLE_STRIP_LOG 0
#endif

// GCC can be told that a certain branch is not likely to be taken (for
// instance, a CHECK failure), and use that information in static analysis.
// Giving it this information can help it optimize for the common case in
// the absence of better information (ie. -fprofile-arcs).
//
#ifndef GOOGLE_PREDICT_BRANCH_NOT_TAKEN
#if 0
#define GOOGLE_PREDICT_BRANCH_NOT_TAKEN(x) (__builtin_expect(x, 0))
#else
#define GOOGLE_PREDICT_BRANCH_NOT_TAKEN(x) x
#endif
#endif

#ifndef GOOGLE_PREDICT_FALSE
#if 0
#define GOOGLE_PREDICT_FALSE(x) (__builtin_expect(x, 0))
#else
#define GOOGLE_PREDICT_FALSE(x) x
#endif
#endif

#ifndef GOOGLE_PREDICT_TRUE
#if 0
#define GOOGLE_PREDICT_TRUE(x) (__builtin_expect(!!(x), 1))
#else
#define GOOGLE_PREDICT_TRUE(x) x
#endif
#endif

// 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 capture log messages in a string, rather than reporting them
// immediately:
//
//   vector<string> errors;
//   LOG_STRING(ERROR, &errors) << "Couldn't parse cookie #" << cookie_num;
//
// This pushes back the new error onto 'errors'; if given a NULL pointer,
// it reports the error via LOG(ERROR).
//
// You can also do conditional logging:
//
//   LOG_IF(INFO, num_cookies > 10) << "Got lots of cookies";
//
// You can also do occasional logging (log every n'th occurrence of an
// event):
//
//   LOG_EVERY_N(INFO, 10) << "Got the " << google::COUNTER << "th cookie";
//
// The above will cause log messages to be output on the 1st, 11th, 21st, ...
// times it is executed.  Note that the special google::COUNTER value is used
// to identify which repetition is happening.
//
// You can also do occasional conditional logging (log every n'th
// occurrence of an event, when condition is satisfied):
//
//   LOG_IF_EVERY_N(INFO, (size > 1024), 10) << "Got the " << google::COUNTER
//                                           << "th big cookie";
//
// You can log messages the first N times your code executes a line. E.g.
//
//   LOG_FIRST_N(INFO, 20) << "Got the " << google::COUNTER << "th cookie";
//
// Outputs log messages for the first 20 times it is executed.
//
// Analogous SYSLOG, SYSLOG_IF, and SYSLOG_EVERY_N macros are available.
// These log to syslog as well as to the normal logs.  If you use these at
// all, you need to be aware that syslog can drastically reduce performance,
// especially if it is configured for remote logging!  Don't use these
// unless you fully understand this and have a concrete need to use them.
// Even then, try to minimize your use of them.
//
// 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";
//
//   DLOG_EVERY_N(INFO, 10) << "Got the " << google::COUNTER << "th cookie";
//
// All "debug mode" logging is compiled away to nothing for non-debug mode
// compiles.
//
// 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=mapreduce=2,file=1,gfs*=3 --v=0
// will cause:
//   a. VLOG(2) and lower messages to be printed from mapreduce.{h,cc}
//   b. VLOG(1) and lower messages to be printed from file.{h,cc}
//   c. VLOG(3) and lower messages to be printed from files prefixed with "gfs"
//   d. 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.
//
// 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 are also VLOG_IF, VLOG_EVERY_N and VLOG_IF_EVERY_N "verbose level"
// condition macros 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";
//   VLOG_EVERY_N(1, 10)
//      << "I'm printed every 10th occurrence, and when you run the program "
//         "with --v=1 or more. Present occurence is " << google::COUNTER;
//   VLOG_IF_EVERY_N(1, (size > 1024), 10)
//      << "I'm printed on every 10th occurence of case when size is more "
//         " than 1024, when you run the program with --v=1 or more. ";
//         "Present occurence is " << google::COUNTER;
//
// The supported severity levels for macros that allow you to specify one
// are (in increasing order of severity) INFO, WARNING, ERROR, and FATAL.
// Note that messages of a given severity are logged not only in the
// logfile for that severity, but also in all logfiles of lower severity.
// E.g., a message of severity FATAL will be logged to the logfiles of
// severity FATAL, ERROR, WARNING, and INFO.
//
// There is also the special severity of DFATAL, which logs FATAL in
// debug mode, ERROR in normal mode.
//
// Very important: logging a message at the FATAL severity level causes
// the program to terminate (after the message is logged).
//
// Unless otherwise specified, logs will be written to the filename
// "<program name>.<hostname>.<user name>.log.<severity level>.", followed
// by the date, time, and pid (you can't prevent the date, time, and pid
// from being in the filename).
//
// The logging code takes two flags:
//     --v=#           set the verbose level
//     --logtostderr   log all the messages to stderr instead of to logfiles

// LOG LINE PREFIX FORMAT
//
// Log lines have this form:
//
//     Lyyyymmdd hh:mm:ss.uuuuuu threadid file:line] msg...
//
// where the fields are defined as follows:
//
//   L                A single character, representing the log level
//                    (eg 'I' for INFO)
//   yyyy             The year
//   mm               The month (zero padded; ie May is '05')
//   dd               The day (zero padded)
//   hh:mm:ss.uuuuuu  Time in hours, minutes and fractional seconds
//   threadid         The space-padded thread ID as returned by GetTID()
//                    (this matches the PID on Linux)
//   file             The file name
//   line             The line number
//   msg              The user-supplied message
//
// Example:
//
//   I1103 11:57:31.739339 24395 google.cc:2341] Command line: ./some_prog
//   I1103 11:57:31.739403 24395 google.cc:2342] Process id 24395
//
// NOTE: although the microseconds are useful for comparing events on
// a single machine, clocks on different machines may not be well
// synchronized.  Hence, use caution when comparing the low bits of
// timestamps from different machines.

#pragma push_macro("DECLARE_VARIABLE")
#pragma push_macro("DECLARE_bool")
#pragma push_macro("DECLARE_string")
#pragma push_macro("DECLARE_int32")
#pragma push_macro("DECLARE_uint32")

#ifdef DECLARE_VARIABLE
#undef DECLARE_VARIABLE
#endif

#ifdef DECLARE_bool
#undef DECLARE_bool
#endif

#ifdef DECLARE_string
#undef DECLARE_string
#endif

#ifdef DECLARE_int32
#undef DECLARE_int32
#endif

#ifdef DECLARE_uint32
#undef DECLARE_uint32
#endif

#ifndef DECLARE_VARIABLE
#define DECLARE_VARIABLE(type, shorttype, name, tn) \
    namespace fL##shorttype                         \
    {                                               \
        extern GLOG_EXPORT type FLAGS_##name;       \
    }                                               \
    using fL##shorttype::FLAGS_##name

// bool specialization
#define DECLARE_bool(name) \
    DECLARE_VARIABLE(bool, B, name, bool)

// int32 specialization
#define DECLARE_int32(name) \
    DECLARE_VARIABLE(google::int32, I, name, int32)

#if !defined(DECLARE_uint32)
// uint32 specialization
#define DECLARE_uint32(name) \
    DECLARE_VARIABLE(google::uint32, U, name, uint32)
#endif // !defined(DECLARE_uint32) && !(0)

// Special case for string, because we have to specify the namespace
// std::string, which doesn't play nicely with our FLAG__namespace hackery.
#define DECLARE_string(name)                          \
    namespace fLS                                     \
    {                                                 \
        extern GLOG_EXPORT std::string &FLAGS_##name; \
    }                                                 \
    using fLS::FLAGS_##name
#endif

// Set whether appending a timestamp to the log file name
DECLARE_bool(timestamp_in_logfile_name);

// Set whether log messages go to stdout instead of logfiles
DECLARE_bool(logtostdout);

// Set color messages logged to stdout (if supported by terminal).
DECLARE_bool(colorlogtostdout);

// Set whether log messages go to stderr instead of logfiles
DECLARE_bool(logtostderr);

// Set whether log messages go to stderr in addition to logfiles.
DECLARE_bool(alsologtostderr);

// Set color messages logged to stderr (if supported by terminal).
DECLARE_bool(colorlogtostderr);

// Log messages at a level >= this flag are automatically sent to
// stderr in addition to log files.
DECLARE_int32(stderrthreshold);

// Set whether the log file header should be written upon creating a file.
DECLARE_bool(log_file_header);

// Set whether the log prefix should be prepended to each line of output.
DECLARE_bool(log_prefix);

// Set whether the year should be included in the log prefix.
DECLARE_bool(log_year_in_prefix);

// Log messages at a level <= this flag are buffered.
// Log messages at a higher level are flushed immediately.
DECLARE_int32(logbuflevel);

// Sets the maximum number of seconds which logs may be buffered for.
DECLARE_int32(logbufsecs);

// Log suppression level: messages logged at a lower level than this
// are suppressed.
DECLARE_int32(minloglevel);

// If specified, logfiles are written into this directory instead of the
// default logging directory.
DECLARE_string(log_dir);

// Set the log file mode.
DECLARE_int32(logfile_mode);

// Sets the path of the directory into which to put additional links
// to the log files.
DECLARE_string(log_link);

DECLARE_int32(v); // in vlog_is_on.cc

DECLARE_string(vmodule); // also in vlog_is_on.cc

// Sets the maximum log file size (in MB).
DECLARE_uint32(max_log_size);

// Sets whether to avoid logging to the disk if the disk is full.
DECLARE_bool(stop_logging_if_full_disk);

// Use UTC time for logging
DECLARE_bool(log_utc_time);

// Log messages below the GOOGLE_STRIP_LOG level will be compiled away for
// security reasons. See LOG(severtiy) below.

// A few definitions of macros that don't generate much code.  Since
// LOG(INFO) and its ilk are used all over our code, it's
// better to have compact code for these operations.

#if GOOGLE_STRIP_LOG == 0
#define COMPACT_GOOGLE_LOG_INFO google::LogMessage( \
    __FILE__, __LINE__)
#define LOG_TO_STRING_INFO(message) google::LogMessage( \
    __FILE__, __LINE__, google::GLOG_INFO, message)
#else
#define COMPACT_GOOGLE_LOG_INFO google::NullStream()
#define LOG_TO_STRING_INFO(message) google::NullStream()
#endif

#if GOOGLE_STRIP_LOG <= 1
#define COMPACT_GOOGLE_LOG_WARNING google::LogMessage( \
    __FILE__, __LINE__, google::GLOG_WARNING)
#define LOG_TO_STRING_WARNING(message) google::LogMessage( \
    __FILE__, __LINE__, google::GLOG_WARNING, message)
#else
#define COMPACT_GOOGLE_LOG_WARNING google::NullStream()
#define LOG_TO_STRING_WARNING(message) google::NullStream()
#endif

#if GOOGLE_STRIP_LOG <= 2
#define COMPACT_GOOGLE_LOG_ERROR google::LogMessage( \
    __FILE__, __LINE__, google::GLOG_ERROR)
#define LOG_TO_STRING_ERROR(message) google::LogMessage( \
    __FILE__, __LINE__, google::GLOG_ERROR, message)
#else
#define COMPACT_GOOGLE_LOG_ERROR google::NullStream()
#define LOG_TO_STRING_ERROR(message) google::NullStream()
#endif

#if GOOGLE_STRIP_LOG <= 3
#define COMPACT_GOOGLE_LOG_FATAL google::LogMessageFatal( \
    __FILE__, __LINE__)
#define LOG_TO_STRING_FATAL(message) google::LogMessage( \
    __FILE__, __LINE__, google::GLOG_FATAL, message)
#else
#define COMPACT_GOOGLE_LOG_FATAL google::NullStreamFatal()
#define LOG_TO_STRING_FATAL(message) google::NullStreamFatal()
#endif

#if defined(NDEBUG) && !defined(DCHECK_ALWAYS_ON)
#define DCHECK_IS_ON() 0
#else
#define DCHECK_IS_ON() 1
#endif

// For DFATAL, we want to use LogMessage (as opposed to
// LogMessageFatal), to be consistent with the original behavior.
#if !DCHECK_IS_ON()
#define COMPACT_GOOGLE_LOG_DFATAL COMPACT_GOOGLE_LOG_ERROR
#elif GOOGLE_STRIP_LOG <= 3
#define COMPACT_GOOGLE_LOG_DFATAL google::LogMessage( \
    __FILE__, __LINE__, google::GLOG_FATAL)
#else
#define COMPACT_GOOGLE_LOG_DFATAL google::NullStreamFatal()
#endif

#define GOOGLE_LOG_INFO(counter) google::LogMessage(__FILE__, __LINE__, google::GLOG_INFO, counter, &google::LogMessage::SendToLog)
#define SYSLOG_INFO(counter)                                           \
    google::LogMessage(__FILE__, __LINE__, google::GLOG_INFO, counter, \
                       &google::LogMessage::SendToSyslogAndLog)
#define GOOGLE_LOG_WARNING(counter)                                       \
    google::LogMessage(__FILE__, __LINE__, google::GLOG_WARNING, counter, \
                       &google::LogMessage::SendToLog)
#define SYSLOG_WARNING(counter)                                           \
    google::LogMessage(__FILE__, __LINE__, google::GLOG_WARNING, counter, \
                       &google::LogMessage::SendToSyslogAndLog)
#define GOOGLE_LOG_ERROR(counter)                                       \
    google::LogMessage(__FILE__, __LINE__, google::GLOG_ERROR, counter, \
                       &google::LogMessage::SendToLog)
#define SYSLOG_ERROR(counter)                                           \
    google::LogMessage(__FILE__, __LINE__, google::GLOG_ERROR, counter, \
                       &google::LogMessage::SendToSyslogAndLog)
#define GOOGLE_LOG_FATAL(counter)                                       \
    google::LogMessage(__FILE__, __LINE__, google::GLOG_FATAL, counter, \
                       &google::LogMessage::SendToLog)
#define SYSLOG_FATAL(counter)                                           \
    google::LogMessage(__FILE__, __LINE__, google::GLOG_FATAL, counter, \
                       &google::LogMessage::SendToSyslogAndLog)
#define GOOGLE_LOG_DFATAL(counter)                                        \
    google::LogMessage(__FILE__, __LINE__, google::DFATAL_LEVEL, counter, \
                       &google::LogMessage::SendToLog)
#define SYSLOG_DFATAL(counter)                                            \
    google::LogMessage(__FILE__, __LINE__, google::DFATAL_LEVEL, counter, \
                       &google::LogMessage::SendToSyslogAndLog)

#if defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__) || defined(__CYGWIN32__)
// A very useful logging macro to log windows errors:
#define LOG_SYSRESULT(result)                                                    \
    if (FAILED(HRESULT_FROM_WIN32(result)))                                      \
    {                                                                            \
        LPSTR message = NULL;                                                    \
        LPSTR msg = reinterpret_cast<LPSTR>(&message);                           \
        DWORD message_length = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |   \
                                                  FORMAT_MESSAGE_FROM_SYSTEM |   \
                                                  FORMAT_MESSAGE_IGNORE_INSERTS, \
                                              0, result, 0, msg, 100, NULL);     \
        if (message_length > 0)                                                  \
        {                                                                        \
            google::LogMessage(__FILE__, __LINE__, google::GLOG_ERROR, 0,        \
                               &google::LogMessage::SendToLog)                   \
                    .stream()                                                    \
                << reinterpret_cast<const char *>(message);                      \
            LocalFree(message);                                                  \
        }                                                                        \
    }
#endif

// We use the preprocessor's merging operator, "##", so that, e.g.,
// LOG(INFO) becomes the token 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(severity) COMPACT_GOOGLE_LOG_##severity.stream()
#define SYSLOG(severity) SYSLOG_##severity(0).stream()

namespace google
{

// They need the definitions of integer types.
#include <glog/log_severity.h>
#include <glog/vlog_is_on.h>

    // Initialize google's logging library. You will see the program name
    // specified by argv0 in log outputs.
    GLOG_EXPORT void InitGoogleLogging(const char *argv0);

#ifdef GLOG_CUSTOM_PREFIX_SUPPORT
    GLOG_EXPORT void InitGoogleLogging(const char *argv0,
                                       CustomPrefixCallback prefix_callback,
                                       void *prefix_callback_data = NULL);
#endif

    // Check if google's logging library has been initialized.
    GLOG_EXPORT bool IsGoogleLoggingInitialized();

    // Shutdown google's logging library.
    GLOG_EXPORT void ShutdownGoogleLogging();

#if defined(__GNUC__)
    typedef void (*logging_fail_func_t)() __attribute__((noreturn));
#else
    typedef void (*logging_fail_func_t)();
#endif

    // Install a function which will be called after LOG(FATAL).
    GLOG_EXPORT void InstallFailureFunction(logging_fail_func_t fail_func);

    // Enable/Disable old log cleaner.
    GLOG_EXPORT void EnableLogCleaner(unsigned int overdue_days);
    GLOG_EXPORT void DisableLogCleaner();
    GLOG_EXPORT void SetApplicationFingerprint(const std::string &fingerprint);

    class LogSink; // defined below

// If a non-NULL sink pointer is given, we push this message to that sink.
// For LOG_TO_SINK we then do normal LOG(severity) logging as well.
// This is useful for capturing messages and passing/storing them
// somewhere more specific than the global log of the process.
// Argument types:
//   LogSink* sink;
//   LogSeverity severity;
// The cast is to disambiguate NULL arguments.
#define LOG_TO_SINK(sink, severity)                 \
    google::LogMessage(                             \
        __FILE__, __LINE__,                         \
        google::GLOG_##severity,                    \
        static_cast<google::LogSink *>(sink), true) \
        .stream()
#define LOG_TO_SINK_BUT_NOT_TO_LOGFILE(sink, severity) \
    google::LogMessage(                                \
        __FILE__, __LINE__,                            \
        google::GLOG_##severity,                       \
        static_cast<google::LogSink *>(sink), false)   \
        .stream()

// If a non-NULL string pointer is given, we write this message to that string.
// We then do normal LOG(severity) logging as well.
// This is useful for capturing messages and storing them somewhere more
// specific than the global log of the process.
// Argument types:
//   string* message;
//   LogSeverity severity;
// The cast is to disambiguate NULL arguments.
// NOTE: LOG(severity) expands to LogMessage().stream() for the specified
// severity.
#define LOG_TO_STRING(severity, message) \
    LOG_TO_STRING_##severity(static_cast<std::string *>(message)).stream()

// If a non-NULL pointer is given, we push the message onto the end
// of a vector of strings; otherwise, we report it with LOG(severity).
// This is handy for capturing messages and perhaps passing them back
// to the caller, rather than reporting them immediately.
// Argument types:
//   LogSeverity severity;
//   vector<string> *outvec;
// The cast is to disambiguate NULL arguments.
#define LOG_STRING(severity, outvec) \
    LOG_TO_STRING_##severity(static_cast<std::vector<std::string> *>(outvec)).stream()

#define LOG_IF(severity, condition) \
    static_cast<void>(0),           \
        !(condition) ? (void)0 : google::LogMessageVoidify() & LOG(severity)
#define SYSLOG_IF(severity, condition) \
    static_cast<void>(0),              \
        !(condition) ? (void)0 : google::LogMessageVoidify() & SYSLOG(severity)

#define LOG_ASSERT(condition) \
    LOG_IF(FATAL, !(condition)) << "Assert failed: " #condition
#define SYSLOG_ASSERT(condition) \
    SYSLOG_IF(FATAL, !(condition)) << "Assert failed: " #condition

// CHECK dies with a fatal error if condition is not true.  It is *not*
// controlled by DCHECK_IS_ON(), so the check will be executed regardless of
// compilation mode.  Therefore, it is safe to do things like:
//    CHECK(fp->Write(x) == 4)
#define CHECK(condition)                                         \
    LOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN(!(condition))) \
        << "Check failed: " #condition " "

    // A container for a string pointer which can be evaluated to a bool -
    // true iff the pointer is NULL.
    struct CheckOpString
    {
        CheckOpString(std::string *str) : str_(str) {}
        // No destructor: if str_ is non-NULL, we're about to LOG(FATAL),
        // so there's no point in cleaning up str_.
        operator bool() const
        {
            return GOOGLE_PREDICT_BRANCH_NOT_TAKEN(str_ != NULL);
        }
        std::string *str_;
    };

    // Function is overloaded for integral types to allow static const
    // integrals declared in classes and not defined to be used as arguments to
    // CHECK* macros. It's not encouraged though.
    template <class T>
    inline const T &GetReferenceableValue(const T &t) { return t; }
    inline char GetReferenceableValue(char t) { return t; }
    inline unsigned char GetReferenceableValue(unsigned char t) { return t; }
    inline signed char GetReferenceableValue(signed char t) { return t; }
    inline short GetReferenceableValue(short t) { return t; }
    inline unsigned short GetReferenceableValue(unsigned short t) { return t; }
    inline int GetReferenceableValue(int t) { return t; }
    inline unsigned int GetReferenceableValue(unsigned int t) { return t; }
    inline long GetReferenceableValue(long t) { return t; }
    inline unsigned long GetReferenceableValue(unsigned long t) { return t; }
#if __cplusplus >= 201103L
    inline long long GetReferenceableValue(long long t)
    {
        return t;
    }
    inline unsigned long long GetReferenceableValue(unsigned long long t)
    {
        return t;
    }
#endif

    // This is a dummy class to define the following operator.
    struct DummyClassToDefineOperator
    {
    };

}

// Define global operator<< to declare using ::operator<<.
// This declaration will allow use to use CHECK macros for user
// defined classes which have operator<< (e.g., stl_logging.h).
inline std::ostream &operator<<(
    std::ostream &out, const google::DummyClassToDefineOperator &)
{
    return out;
}

namespace google
{

    // 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 void MakeCheckOpValueString(std::ostream *os, const T &v)
    {
        (*os) << v;
    }

    // Overrides for char types provide readable values for unprintable
    // characters.
    template <>
    GLOG_EXPORT void MakeCheckOpValueString(std::ostream *os, const char &v);
    template <>
    GLOG_EXPORT void MakeCheckOpValueString(std::ostream *os, const signed char &v);
    template <>
    GLOG_EXPORT void MakeCheckOpValueString(std::ostream *os, const unsigned char &v);

// This is required because nullptr is only present in c++ 11 and later.
#if 1 && __cplusplus >= 201103L
    // Provide printable value for nullptr_t
    template <>
    GLOG_EXPORT void MakeCheckOpValueString(std::ostream *os, const std::nullptr_t &v);
#endif

    // Build the error message string. Specify no inlining for code size.
    template <typename T1, typename T2>
    std::string *MakeCheckOpString(const T1 &v1, const T2 &v2, const char *exprtext);

    namespace base
    {
        namespace internal
        {

            // If "s" is less than base_logging::INFO, returns base_logging::INFO.
            // If "s" is greater than base_logging::FATAL, returns
            // base_logging::ERROR.  Otherwise, returns "s".
            LogSeverity NormalizeSeverity(LogSeverity s);

        } // namespace internal

        // A helper class for formatting "expr (V1 vs. V2)" in a CHECK_XX
        // statement.  See MakeCheckOpString for sample usage.  Other
        // approaches were considered: use of a template method (e.g.,
        // base::BuildCheckOpString(exprtext, base::Print<T1>, &v1,
        // base::Print<T2>, &v2), however this approach has complications
        // related to volatile arguments and function-pointer arguments).
        class GLOG_EXPORT CheckOpMessageBuilder
        {
        public:
            // Inserts "exprtext" and " (" to the stream.
            explicit CheckOpMessageBuilder(const char *exprtext);
            // Deletes "stream_".
            ~CheckOpMessageBuilder();
            // For inserting the first variable.
            std::ostream *ForVar1() { return stream_; }
            // For inserting the second variable (adds an intermediate " vs. ").
            std::ostream *ForVar2();
            // Get the result (inserts the closing ")").
            std::string *NewString();

        private:
            std::ostringstream *stream_;
        };

    } // namespace base

    template <typename T1, typename T2>
    std::string *MakeCheckOpString(const T1 &v1, const T2 &v2, const char *exprtext)
    {
        base::CheckOpMessageBuilder comb(exprtext);
        MakeCheckOpValueString(comb.ForVar1(), v1);
        MakeCheckOpValueString(comb.ForVar2(), v2);
        return comb.NewString();
    }

// 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 <typename T1, typename T2>                                  \
    inline std::string *name##Impl(const T1 &v1, const T2 &v2,           \
                                   const char *exprtext)                 \
    {                                                                    \
        if (GOOGLE_PREDICT_TRUE(v1 op v2))                               \
            return NULL;                                                 \
        else                                                             \
            return MakeCheckOpString(v1, v2, exprtext);                  \
    }                                                                    \
    inline std::string *name##Impl(int v1, int v2, const char *exprtext) \
    {                                                                    \
        return name##Impl<int, int>(v1, v2, exprtext);                   \
    }

    // We use the full name Check_EQ, Check_NE, etc. in case the file including
    // base/logging.h provides its own #defines for the simpler names EQ, NE, etc.
    // This happens if, for example, those are used as token names in a
    // yacc grammar.
    DEFINE_CHECK_OP_IMPL(Check_EQ, ==) // Compilation error with CHECK_EQ(NULL, x)?
    DEFINE_CHECK_OP_IMPL(Check_NE, !=) // Use CHECK(x == NULL) instead.
    DEFINE_CHECK_OP_IMPL(Check_LE, <=)
    DEFINE_CHECK_OP_IMPL(Check_LT, <)
    DEFINE_CHECK_OP_IMPL(Check_GE, >=)
    DEFINE_CHECK_OP_IMPL(Check_GT, >)
#undef DEFINE_CHECK_OP_IMPL

    // Helper macro for binary operators.
    // Don't use this macro directly in your code, use CHECK_EQ et al below.

#if defined(STATIC_ANALYSIS)
// Only for static analysis tool to know that it is equivalent to assert
#define CHECK_OP_LOG(name, op, val1, val2, log) CHECK((val1)op(val2))
#elif DCHECK_IS_ON()
    // In debug mode, avoid constructing CheckOpStrings if possible,
    // to reduce the overhead of CHECK statments by 2x.
    // Real DCHECK-heavy tests have seen 1.5x speedups.

    // The meaning of "string" might be different between now and
    // when this macro gets invoked (e.g., if someone is experimenting
    // with other string implementations that get defined after this
    // file is included).  Save the current meaning now and use it
    // in the macro.
    typedef std::string _Check_string;
#define CHECK_OP_LOG(name, op, val1, val2, log)         \
    while (google::_Check_string *_result =             \
               google::Check##name##Impl(               \
                   google::GetReferenceableValue(val1), \
                   google::GetReferenceableValue(val2), \
                   #val1 " " #op " " #val2))            \
    log(__FILE__, __LINE__,                             \
        google::CheckOpString(_result))                 \
        .stream()
#else
// In optimized mode, use CheckOpString to hint to compiler that
// the while condition is unlikely.
#define CHECK_OP_LOG(name, op, val1, val2, log)         \
    while (google::CheckOpString _result =              \
               google::Check##name##Impl(               \
                   google::GetReferenceableValue(val1), \
                   google::GetReferenceableValue(val2), \
                   #val1 " " #op " " #val2))            \
    log(__FILE__, __LINE__, _result).stream()
#endif // STATIC_ANALYSIS, DCHECK_IS_ON()

#if GOOGLE_STRIP_LOG <= 3
#define CHECK_OP(name, op, val1, val2) \
    CHECK_OP_LOG(name, op, val1, val2, google::LogMessageFatal)
#else
#define CHECK_OP(name, op, val1, val2) \
    CHECK_OP_LOG(name, op, val1, val2, google::NullStreamFatal)
#endif // STRIP_LOG <= 3

    // Equality/Inequality checks - compare two values, and log a FATAL 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:
    //   CHECK_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:
    //   CHECK_EQ(string("abc")[1], 'b');
    //
    // WARNING: These don't 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 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)

    // Check that the input is non NULL.  This very useful in constructor
    // initializer lists.

#define CHECK_NOTNULL(val) \
    google::CheckNotNull(__FILE__, __LINE__, "'" #val "' Must be non NULL", (val))

// Helper functions for string comparisons.
// To avoid bloat, the definitions are in logging.cc.
#define DECLARE_CHECK_STROP_IMPL(func, expected)          \
    GLOG_EXPORT std::string *Check##func##expected##Impl( \
        const char *s1, const char *s2, const char *names);
    DECLARE_CHECK_STROP_IMPL(strcmp, true)
    DECLARE_CHECK_STROP_IMPL(strcmp, false)
    DECLARE_CHECK_STROP_IMPL(strcasecmp, true)
    DECLARE_CHECK_STROP_IMPL(strcasecmp, false)
#undef DECLARE_CHECK_STROP_IMPL

// Helper macro for string comparisons.
// Don't use this macro directly in your code, use CHECK_STREQ et al below.
#define CHECK_STROP(func, op, expected, s1, s2)                          \
    while (google::CheckOpString _result =                               \
               google::Check##func##expected##Impl((s1), (s2),           \
                                                   #s1 " " #op " " #s2)) \
    LOG(FATAL) << *_result.str_

    // String (char*) equality/inequality checks.
    // CASE versions are case-insensitive.
    //
    // Note that "s1" and "s2" may be temporary strings which are destroyed
    // by the compiler at the end of the current "full expression"
    // (e.g. CHECK_STREQ(Foo().c_str(), Bar().c_str())).

#define CHECK_STREQ(s1, s2) CHECK_STROP(strcmp, ==, true, s1, s2)
#define CHECK_STRNE(s1, s2) CHECK_STROP(strcmp, !=, false, s1, s2)
#define CHECK_STRCASEEQ(s1, s2) CHECK_STROP(strcasecmp, ==, true, s1, s2)
#define CHECK_STRCASENE(s1, s2) CHECK_STROP(strcasecmp, !=, false, s1, s2)

#define CHECK_INDEX(I, A) CHECK(I < (sizeof(A) / sizeof(A[0])))
#define CHECK_BOUND(B, A) CHECK(B <= (sizeof(A) / sizeof(A[0])))

#define CHECK_DOUBLE_EQ(val1, val2)                    \
    do                                                 \
    {                                                  \
        CHECK_LE((val1), (val2) + 0.000000000000001L); \
        CHECK_GE((val1), (val2)-0.000000000000001L);   \
    } while (0)

#define CHECK_NEAR(val1, val2, margin)       \
    do                                       \
    {                                        \
        CHECK_LE((val1), (val2) + (margin)); \
        CHECK_GE((val1), (val2) - (margin)); \
    } while (0)

    // perror()..googly style!
    //
    // PLOG() and PLOG_IF() and PCHECK() behave exactly like their LOG* and
    // CHECK equivalents with the addition that they postpend a description
    // of the current state of errno to their output lines.

#define PLOG(severity) GOOGLE_PLOG(severity, 0).stream()

#define GOOGLE_PLOG(severity, counter)                        \
    google::ErrnoLogMessage(                                  \
        __FILE__, __LINE__, google::GLOG_##severity, counter, \
        &google::LogMessage::SendToLog)

#define PLOG_IF(severity, condition) \
    static_cast<void>(0),            \
        !(condition) ? (void)0 : google::LogMessageVoidify() & PLOG(severity)

// A CHECK() macro that postpends errno if the condition is false. E.g.
//
// if (poll(fds, nfds, timeout) == -1) { PCHECK(errno == EINTR); ... }
#define PCHECK(condition)                                         \
    PLOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN(!(condition))) \
        << "Check failed: " #condition " "

// A CHECK() macro that lets you assert the success of a function that
// returns -1 and sets errno in case of an error. E.g.
//
// CHECK_ERR(mkdir(path, 0700));
//
// or
//
// int fd = open(filename, flags); CHECK_ERR(fd) << ": open " << filename;
#define CHECK_ERR(invocation)                                           \
    PLOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN((invocation) == -1)) \
        << #invocation

// Use macro expansion to create, for each use of LOG_EVERY_N(), static
// variables with the __LINE__ expansion as part of the variable name.
#define LOG_EVERY_N_VARNAME(base, line) LOG_EVERY_N_VARNAME_CONCAT(base, line)
#define LOG_EVERY_N_VARNAME_CONCAT(base, line) base##line

#define LOG_OCCURRENCES LOG_EVERY_N_VARNAME(occurrences_, __LINE__)
#define LOG_OCCURRENCES_MOD_N LOG_EVERY_N_VARNAME(occurrences_mod_n_, __LINE__)

#if 1 && __cplusplus >= 201103L
#define GLOG_CONSTEXPR constexpr
#else
#define GLOG_CONSTEXPR const
#endif

#define LOG_TIME_PERIOD LOG_EVERY_N_VARNAME(timePeriod_, __LINE__)
#define LOG_PREVIOUS_TIME_RAW LOG_EVERY_N_VARNAME(previousTimeRaw_, __LINE__)
#define LOG_TIME_DELTA LOG_EVERY_N_VARNAME(deltaTime_, __LINE__)
#define LOG_CURRENT_TIME LOG_EVERY_N_VARNAME(currentTime_, __LINE__)
#define LOG_PREVIOUS_TIME LOG_EVERY_N_VARNAME(previousTime_, __LINE__)

#if defined(__has_feature)
#if __has_feature(thread_sanitizer)
#define GLOG_SANITIZE_THREAD 1
#endif
#endif

#if !defined(GLOG_SANITIZE_THREAD) && defined(__SANITIZE_THREAD__) && __SANITIZE_THREAD__
#define GLOG_SANITIZE_THREAD 1
#endif

#if defined(GLOG_SANITIZE_THREAD)
#define GLOG_IFDEF_THREAD_SANITIZER(X) X
#else
#define GLOG_IFDEF_THREAD_SANITIZER(X)
#endif

#if defined(GLOG_SANITIZE_THREAD)
} // namespace google

// We need to identify the static variables as "benign" races
// to avoid noisy reports from TSAN.
extern "C" void AnnotateBenignRaceSized(
    const char *file,
    int line,
    const volatile void *mem,
    size_t size,
    const char *description);

namespace google
{
#endif

#if __cplusplus >= 201103L && 1 && 1 // Have <chrono> and <atomic>
#define SOME_KIND_OF_LOG_EVERY_T(severity, seconds)                                                                                                         \
    GLOG_CONSTEXPR std::chrono::nanoseconds LOG_TIME_PERIOD = std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::duration<double>(seconds)); \
    static std::atomic<google::int64> LOG_PREVIOUS_TIME_RAW;                                                                                                \
    GLOG_IFDEF_THREAD_SANITIZER(                                                                                                                            \
        AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_TIME_PERIOD, sizeof(google::int64), ""));                                                          \
    GLOG_IFDEF_THREAD_SANITIZER(                                                                                                                            \
        AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_PREVIOUS_TIME_RAW, sizeof(google::int64), ""));                                                    \
    const auto LOG_CURRENT_TIME = std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::steady_clock::now().time_since_epoch());                \
    const auto LOG_PREVIOUS_TIME = LOG_PREVIOUS_TIME_RAW.load(std::memory_order_relaxed);                                                                   \
    const auto LOG_TIME_DELTA = LOG_CURRENT_TIME - std::chrono::nanoseconds(LOG_PREVIOUS_TIME);                                                             \
    if (LOG_TIME_DELTA > LOG_TIME_PERIOD)                                                                                                                   \
        LOG_PREVIOUS_TIME_RAW.store(std::chrono::duration_cast<std::chrono::nanoseconds>(LOG_CURRENT_TIME).count(), std::memory_order_relaxed);             \
    if (LOG_TIME_DELTA > LOG_TIME_PERIOD)                                                                                                                   \
    google::LogMessage(                                                                                                                                     \
        __FILE__, __LINE__, google::GLOG_##severity)                                                                                                        \
        .stream()
#elif defined(GLOG_OS_WINDOWS)
#define SOME_KIND_OF_LOG_EVERY_T(severity, seconds)                                                               \
    GLOG_CONSTEXPR LONGLONG LOG_TIME_PERIOD = (seconds)*LONGLONG(1000000000);                                     \
    static LARGE_INTEGER LOG_PREVIOUS_TIME;                                                                       \
    LONGLONG LOG_TIME_DELTA;                                                                                      \
    {                                                                                                             \
        LARGE_INTEGER currTime;                                                                                   \
        LARGE_INTEGER freq;                                                                                       \
        QueryPerformanceCounter(&currTime);                                                                       \
        QueryPerformanceFrequency(&freq);                                                                         \
        InterlockedCompareExchange64(&LOG_PREVIOUS_TIME.QuadPart, currTime.QuadPart, 0);                          \
        LOG_TIME_DELTA = (currTime.QuadPart - LOG_PREVIOUS_TIME.QuadPart) * LONGLONG(1000000000) / freq.QuadPart; \
        if (LOG_TIME_DELTA > LOG_TIME_PERIOD)                                                                     \
            InterlockedExchange64(&LOG_PREVIOUS_TIME.QuadPart, currTime.QuadPart);                                \
    }                                                                                                             \
    if (LOG_TIME_DELTA > LOG_TIME_PERIOD)                                                                         \
    google::LogMessage(                                                                                           \
        __FILE__, __LINE__, google::GLOG_##severity)                                                              \
        .stream()
#else
#define SOME_KIND_OF_LOG_EVERY_T(severity, seconds)                                                   \
    GLOG_CONSTEXPR google::int64 LOG_TIME_PERIOD(seconds * 1000000000);                               \
    static google::int64 LOG_PREVIOUS_TIME;                                                           \
    google::int64 LOG_TIME_DELTA = 0;                                                                 \
    {                                                                                                 \
        timespec currentTime = {};                                                                    \
        clock_gettime(CLOCK_MONOTONIC, &currentTime);                                                 \
        LOG_TIME_DELTA = (currentTime.tv_sec * 1000000000 + currentTime.tv_nsec) - LOG_PREVIOUS_TIME; \
    }                                                                                                 \
    if (LOG_TIME_DELTA > LOG_TIME_PERIOD)                                                             \
        __sync_add_and_fetch(&LOG_PREVIOUS_TIME, LOG_TIME_DELTA);                                     \
    if (LOG_TIME_DELTA > LOG_TIME_PERIOD)                                                             \
    google::LogMessage(                                                                               \
        __FILE__, __LINE__, google::GLOG_##severity)                                                  \
        .stream()
#endif

#if 1 && __cplusplus >= 201103L
#define SOME_KIND_OF_LOG_EVERY_N(severity, n, what_to_do)                                                              \
    static std::atomic<int> LOG_OCCURRENCES(0), LOG_OCCURRENCES_MOD_N(0);                                              \
    GLOG_IFDEF_THREAD_SANITIZER(AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_OCCURRENCES, sizeof(int), ""));       \
    GLOG_IFDEF_THREAD_SANITIZER(AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_OCCURRENCES_MOD_N, sizeof(int), "")); \
    ++LOG_OCCURRENCES;                                                                                                 \
    if (++LOG_OCCURRENCES_MOD_N > n)                                                                                   \
        LOG_OCCURRENCES_MOD_N -= n;                                                                                    \
    if (LOG_OCCURRENCES_MOD_N == 1)                                                                                    \
    google::LogMessage(                                                                                                \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES,                                                  \
        &what_to_do)                                                                                                   \
        .stream()

#define SOME_KIND_OF_LOG_IF_EVERY_N(severity, condition, n, what_to_do)                                                \
    static std::atomic<int> LOG_OCCURRENCES(0), LOG_OCCURRENCES_MOD_N(0);                                              \
    GLOG_IFDEF_THREAD_SANITIZER(AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_OCCURRENCES, sizeof(int), ""));       \
    GLOG_IFDEF_THREAD_SANITIZER(AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_OCCURRENCES_MOD_N, sizeof(int), "")); \
    ++LOG_OCCURRENCES;                                                                                                 \
    if ((condition) &&                                                                                                 \
        ((LOG_OCCURRENCES_MOD_N = (LOG_OCCURRENCES_MOD_N + 1) % n) == (1 % n)))                                        \
    google::LogMessage(                                                                                                \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES,                                                  \
        &what_to_do)                                                                                                   \
        .stream()

#define SOME_KIND_OF_PLOG_EVERY_N(severity, n, what_to_do)                                                             \
    static std::atomic<int> LOG_OCCURRENCES(0), LOG_OCCURRENCES_MOD_N(0);                                              \
    GLOG_IFDEF_THREAD_SANITIZER(AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_OCCURRENCES, sizeof(int), ""));       \
    GLOG_IFDEF_THREAD_SANITIZER(AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_OCCURRENCES_MOD_N, sizeof(int), "")); \
    ++LOG_OCCURRENCES;                                                                                                 \
    if (++LOG_OCCURRENCES_MOD_N > n)                                                                                   \
        LOG_OCCURRENCES_MOD_N -= n;                                                                                    \
    if (LOG_OCCURRENCES_MOD_N == 1)                                                                                    \
    google::ErrnoLogMessage(                                                                                           \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES,                                                  \
        &what_to_do)                                                                                                   \
        .stream()

#define SOME_KIND_OF_LOG_FIRST_N(severity, n, what_to_do)                                                        \
    static std::atomic<int> LOG_OCCURRENCES(0);                                                                  \
    GLOG_IFDEF_THREAD_SANITIZER(AnnotateBenignRaceSized(__FILE__, __LINE__, &LOG_OCCURRENCES, sizeof(int), "")); \
    if (LOG_OCCURRENCES <= n)                                                                                    \
        ++LOG_OCCURRENCES;                                                                                       \
    if (LOG_OCCURRENCES <= n)                                                                                    \
    google::LogMessage(                                                                                          \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES,                                            \
        &what_to_do)                                                                                             \
        .stream()

#elif defined(GLOG_OS_WINDOWS)

#define SOME_KIND_OF_LOG_EVERY_N(severity, n, what_to_do)             \
    static volatile unsigned LOG_OCCURRENCES = 0;                     \
    static volatile unsigned LOG_OCCURRENCES_MOD_N = 0;               \
    InterlockedIncrement(&LOG_OCCURRENCES);                           \
    if (InterlockedIncrement(&LOG_OCCURRENCES_MOD_N) > n)             \
        InterlockedExchangeSubtract(&LOG_OCCURRENCES_MOD_N, n);       \
    if (LOG_OCCURRENCES_MOD_N == 1)                                   \
    google::LogMessage(                                               \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES, \
        &what_to_do)                                                  \
        .stream()

#define SOME_KIND_OF_LOG_IF_EVERY_N(severity, condition, n, what_to_do)                           \
    static volatile unsigned LOG_OCCURRENCES = 0;                                                 \
    static volatile unsigned LOG_OCCURRENCES_MOD_N = 0;                                           \
    InterlockedIncrement(&LOG_OCCURRENCES);                                                       \
    if ((condition) &&                                                                            \
        ((InterlockedIncrement(&LOG_OCCURRENCES_MOD_N),                                           \
          (LOG_OCCURRENCES_MOD_N > n && InterlockedExchangeSubtract(&LOG_OCCURRENCES_MOD_N, n))), \
         LOG_OCCURRENCES_MOD_N == 1))                                                             \
    google::LogMessage(                                                                           \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES,                             \
        &what_to_do)                                                                              \
        .stream()

#define SOME_KIND_OF_PLOG_EVERY_N(severity, n, what_to_do)            \
    static volatile unsigned LOG_OCCURRENCES = 0;                     \
    static volatile unsigned LOG_OCCURRENCES_MOD_N = 0;               \
    InterlockedIncrement(&LOG_OCCURRENCES);                           \
    if (InterlockedIncrement(&LOG_OCCURRENCES_MOD_N) > n)             \
        InterlockedExchangeSubtract(&LOG_OCCURRENCES_MOD_N, n);       \
    if (LOG_OCCURRENCES_MOD_N == 1)                                   \
    google::ErrnoLogMessage(                                          \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES, \
        &what_to_do)                                                  \
        .stream()

#define SOME_KIND_OF_LOG_FIRST_N(severity, n, what_to_do)             \
    static volatile unsigned LOG_OCCURRENCES = 0;                     \
    if (LOG_OCCURRENCES <= n)                                         \
        InterlockedIncrement(&LOG_OCCURRENCES);                       \
    if (LOG_OCCURRENCES <= n)                                         \
    google::LogMessage(                                               \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES, \
        &what_to_do)                                                  \
        .stream()

#else

#define SOME_KIND_OF_LOG_EVERY_N(severity, n, what_to_do)             \
    static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0;        \
    __sync_add_and_fetch(&LOG_OCCURRENCES, 1);                        \
    if (__sync_add_and_fetch(&LOG_OCCURRENCES_MOD_N, 1) > n)          \
        __sync_sub_and_fetch(&LOG_OCCURRENCES_MOD_N, n);              \
    if (LOG_OCCURRENCES_MOD_N == 1)                                   \
    google::LogMessage(                                               \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES, \
        &what_to_do)                                                  \
        .stream()

#define SOME_KIND_OF_LOG_IF_EVERY_N(severity, condition, n, what_to_do)                              \
    static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0;                                       \
    __sync_add_and_fetch(&LOG_OCCURRENCES, 1);                                                       \
    if ((condition) &&                                                                               \
        (__sync_add_and_fetch(&LOG_OCCURRENCES_MOD_N, 1) || true) &&                                 \
        ((LOG_OCCURRENCES_MOD_N >= n && __sync_sub_and_fetch(&LOG_OCCURRENCES_MOD_N, n)) || true) && \
        LOG_OCCURRENCES_MOD_N == (1 % n))                                                            \
    google::LogMessage(                                                                              \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES,                                \
        &what_to_do)                                                                                 \
        .stream()

#define SOME_KIND_OF_PLOG_EVERY_N(severity, n, what_to_do)            \
    static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0;        \
    __sync_add_and_fetch(&LOG_OCCURRENCES, 1);                        \
    if (__sync_add_and_fetch(&LOG_OCCURRENCES_MOD_N, 1) > n)          \
        __sync_sub_and_fetch(&LOG_OCCURRENCES_MOD_N, n);              \
    if (LOG_OCCURRENCES_MOD_N == 1)                                   \
    google::ErrnoLogMessage(                                          \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES, \
        &what_to_do)                                                  \
        .stream()

#define SOME_KIND_OF_LOG_FIRST_N(severity, n, what_to_do)             \
    static int LOG_OCCURRENCES = 0;                                   \
    if (LOG_OCCURRENCES <= n)                                         \
        __sync_add_and_fetch(&LOG_OCCURRENCES, 1);                    \
    if (LOG_OCCURRENCES <= n)                                         \
    google::LogMessage(                                               \
        __FILE__, __LINE__, google::GLOG_##severity, LOG_OCCURRENCES, \
        &what_to_do)                                                  \
        .stream()
#endif

    namespace glog_internal_namespace_
    {
        template <bool>
        struct CompileAssert
        {
        };
        struct CrashReason;

        // Returns true if FailureSignalHandler is installed.
        // Needs to be exported since it's used by the signalhandler_unittest.
        GLOG_EXPORT bool IsFailureSignalHandlerInstalled();
    } // namespace glog_internal_namespace_

#define LOG_EVERY_N(severity, n) \
    SOME_KIND_OF_LOG_EVERY_N(severity, (n), google::LogMessage::SendToLog)

#define LOG_EVERY_T(severity, T) SOME_KIND_OF_LOG_EVERY_T(severity, (T))

#define SYSLOG_EVERY_N(severity, n) \
    SOME_KIND_OF_LOG_EVERY_N(severity, (n), google::LogMessage::SendToSyslogAndLog)

#define PLOG_EVERY_N(severity, n) \
    SOME_KIND_OF_PLOG_EVERY_N(severity, (n), google::LogMessage::SendToLog)

#define LOG_FIRST_N(severity, n) \
    SOME_KIND_OF_LOG_FIRST_N(severity, (n), google::LogMessage::SendToLog)

#define LOG_IF_EVERY_N(severity, condition, n) \
    SOME_KIND_OF_LOG_IF_EVERY_N(severity, (condition), (n), google::LogMessage::SendToLog)

    // We want the special COUNTER value available for LOG_EVERY_X()'ed messages
    enum PRIVATE_Counter
    {
        COUNTER
    };

#ifdef GLOG_NO_ABBREVIATED_SEVERITIES
// 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.
#define COMPACT_GOOGLE_LOG_0 COMPACT_GOOGLE_LOG_ERROR
#define SYSLOG_0 SYSLOG_ERROR
#define LOG_TO_STRING_0 LOG_TO_STRING_ERROR
    // Needed for LOG_IS_ON(ERROR).
    const LogSeverity GLOG_0 = GLOG_ERROR;
#else
// Users may include windows.h after logging.h without
// GLOG_NO_ABBREVIATED_SEVERITIES nor WIN32_LEAN_AND_MEAN.
// For this case, we cannot detect if ERROR is defined before users
// actually use ERROR. Let's make an undefined symbol to warn users.
#define GLOG_ERROR_MSG ERROR_macro_is_defined_Define_GLOG_NO_ABBREVIATED_SEVERITIES_before_including_logging_h_See_the_document_for_detail
#define COMPACT_GOOGLE_LOG_0 GLOG_ERROR_MSG
#define SYSLOG_0 GLOG_ERROR_MSG
#define LOG_TO_STRING_0 GLOG_ERROR_MSG
#define GLOG_0 GLOG_ERROR_MSG
#endif

    // Plus some debug-logging macros that get compiled to nothing for production

#if DCHECK_IS_ON()

#define DLOG(severity) LOG(severity)
#define DVLOG(verboselevel) VLOG(verboselevel)
#define DLOG_IF(severity, condition) LOG_IF(severity, condition)
#define DLOG_EVERY_N(severity, n) LOG_EVERY_N(severity, n)
#define DLOG_IF_EVERY_N(severity, condition, n) \
    LOG_IF_EVERY_N(severity, condition, n)
#define DLOG_ASSERT(condition) LOG_ASSERT(condition)

// debug-only checking.  executed if DCHECK_IS_ON().
#define DCHECK(condition) CHECK(condition)
#define DCHECK_EQ(val1, val2) CHECK_EQ(val1, val2)
#define DCHECK_NE(val1, val2) CHECK_NE(val1, val2)
#define DCHECK_LE(val1, val2) CHECK_LE(val1, val2)
#define DCHECK_LT(val1, val2) CHECK_LT(val1, val2)
#define DCHECK_GE(val1, val2) CHECK_GE(val1, val2)
#define DCHECK_GT(val1, val2) CHECK_GT(val1, val2)
#define DCHECK_NOTNULL(val) CHECK_NOTNULL(val)
#define DCHECK_STREQ(str1, str2) CHECK_STREQ(str1, str2)
#define DCHECK_STRCASEEQ(str1, str2) CHECK_STRCASEEQ(str1, str2)
#define DCHECK_STRNE(str1, str2) CHECK_STRNE(str1, str2)
#define DCHECK_STRCASENE(str1, str2) CHECK_STRCASENE(str1, str2)

#else // !DCHECK_IS_ON()

#define DLOG(severity)    \
    static_cast<void>(0), \
        true ? (void)0 : google::LogMessageVoidify() & LOG(severity)

#define DVLOG(verboselevel) \
    static_cast<void>(0),   \
        (true || !VLOG_IS_ON(verboselevel)) ? (void)0 : google::LogMessageVoidify() & LOG(INFO)

#define DLOG_IF(severity, condition) \
    static_cast<void>(0),            \
        (true || !(condition)) ? (void)0 : google::LogMessageVoidify() & LOG(severity)

#define DLOG_EVERY_N(severity, n) \
    static_cast<void>(0),         \
        true ? (void)0 : google::LogMessageVoidify() & LOG(severity)

#define DLOG_IF_EVERY_N(severity, condition, n) \
    static_cast<void>(0),                       \
        (true || !(condition)) ? (void)0 : google::LogMessageVoidify() & LOG(severity)

#define DLOG_ASSERT(condition) \
    static_cast<void>(0),      \
        true ? (void)0 : LOG_ASSERT(condition)

// MSVC warning C4127: conditional expression is constant
#define DCHECK(condition)                \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK(condition)

#define DCHECK_EQ(val1, val2)            \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_EQ(val1, val2)

#define DCHECK_NE(val1, val2)            \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_NE(val1, val2)

#define DCHECK_LE(val1, val2)            \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_LE(val1, val2)

#define DCHECK_LT(val1, val2)            \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_LT(val1, val2)

#define DCHECK_GE(val1, val2)            \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_GE(val1, val2)

#define DCHECK_GT(val1, val2)            \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_GT(val1, val2)

// You may see warnings in release mode if you don't use the return
// value of DCHECK_NOTNULL. Please just use DCHECK for such cases.
#define DCHECK_NOTNULL(val) (val)

#define DCHECK_STREQ(str1, str2)         \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_STREQ(str1, str2)

#define DCHECK_STRCASEEQ(str1, str2)     \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_STRCASEEQ(str1, str2)

#define DCHECK_STRNE(str1, str2)         \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_STRNE(str1, str2)

#define DCHECK_STRCASENE(str1, str2)     \
    GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
    while (false)                        \
        GLOG_MSVC_POP_WARNING()          \
    CHECK_STRCASENE(str1, str2)

#endif // DCHECK_IS_ON()

    // Log only in verbose mode.

#define VLOG(verboselevel) LOG_IF(INFO, VLOG_IS_ON(verboselevel))

#define VLOG_IF(verboselevel, condition) \
    LOG_IF(INFO, (condition) && VLOG_IS_ON(verboselevel))

#define VLOG_EVERY_N(verboselevel, n) \
    LOG_IF_EVERY_N(INFO, VLOG_IS_ON(verboselevel), n)

#define VLOG_IF_EVERY_N(verboselevel, condition, n) \
    LOG_IF_EVERY_N(INFO, (condition) && VLOG_IS_ON(verboselevel), n)

    namespace base_logging
    {

        // LogMessage::LogStream is a std::ostream backed by this streambuf.
        // This class ignores overflow and leaves two bytes at the end of the
        // buffer to allow for a '\n' and '\0'.
        class GLOG_EXPORT LogStreamBuf : public std::streambuf
        {
        public:
            // REQUIREMENTS: "len" must be >= 2 to account for the '\n' and '\0'.
            LogStreamBuf(char *buf, int len)
            {
                setp(buf, buf + len - 2);
            }

            // This effectively ignores overflow.
            int_type overflow(int_type ch)
            {
                return ch;
            }

            // Legacy public ostrstream method.
            size_t pcount() const { return static_cast<size_t>(pptr() - pbase()); }
            char *pbase() const { return std::streambuf::pbase(); }
        };

    } // namespace base_logging

    //
    // 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 GLOG_EXPORT LogMessage
    {
    public:
        enum
        {
            // Passing kNoLogPrefix for the line number disables the
            // log-message prefix. Useful for using the LogMessage
            // infrastructure as a printing utility. See also the --log_prefix
            // flag for controlling the log-message prefix on an
            // application-wide basis.
            kNoLogPrefix = -1
        };

        // LogStream inherit from non-DLL-exported class (std::ostrstream)
        // and VC++ produces a warning for this situation.
        // However, MSDN says "C4275 can be ignored in Microsoft Visual C++
        // 2005 if you are deriving from a type in the Standard C++ Library"
        // http://msdn.microsoft.com/en-us/library/3tdb471s(VS.80).aspx
        // Let's just ignore the warning.
        GLOG_MSVC_PUSH_DISABLE_WARNING(4275)
        class GLOG_EXPORT LogStream : public std::ostream
        {
            GLOG_MSVC_POP_WARNING()
        public:
            LogStream(char *buf, int len, int64 ctr)
                : std::ostream(NULL),
                  streambuf_(buf, len),
                  ctr_(ctr),
                  self_(this)
            {
                rdbuf(&streambuf_);
            }

            int64 ctr() const { return ctr_; }
            void set_ctr(int64 ctr) { ctr_ = ctr; }
            LogStream *self() const { return self_; }

            // Legacy std::streambuf methods.
            size_t pcount() const { return streambuf_.pcount(); }
            char *pbase() const { return streambuf_.pbase(); }
            char *str() const { return pbase(); }

        private:
            LogStream(const LogStream &);
            LogStream &operator=(const LogStream &);
            base_logging::LogStreamBuf streambuf_;
            int64 ctr_;       // Counter hack (for the LOG_EVERY_X() macro)
            LogStream *self_; // Consistency check hack
        };

    public:
        // icc 8 requires this typedef to avoid an internal compiler error.
        typedef void (LogMessage::*SendMethod)();

        LogMessage(const char *file, int line, LogSeverity severity, int64 ctr,
                   SendMethod send_method);

        // Two special constructors that generate reduced amounts of code at
        // LOG call sites for common cases.

        // Used for LOG(INFO): Implied are:
        // severity = INFO, ctr = 0, send_method = &LogMessage::SendToLog.
        //
        // Using this constructor instead of the more complex constructor above
        // saves 19 bytes per call site.
        LogMessage(const char *file, int line);

        // Used for LOG(severity) where severity != INFO.  Implied
        // are: ctr = 0, send_method = &LogMessage::SendToLog
        //
        // Using this constructor instead of the more complex constructor above
        // saves 17 bytes per call site.
        LogMessage(const char *file, int line, LogSeverity severity);

        // Constructor to log this message to a specified sink (if not NULL).
        // Implied are: ctr = 0, send_method = &LogMessage::SendToSinkAndLog if
        // also_send_to_log is true, send_method = &LogMessage::SendToSink otherwise.
        LogMessage(const char *file, int line, LogSeverity severity, LogSink *sink,
                   bool also_send_to_log);

        // Constructor where we also give a vector<string> pointer
        // for storing the messages (if the pointer is not NULL).
        // Implied are: ctr = 0, send_method = &LogMessage::SaveOrSendToLog.
        LogMessage(const char *file, int line, LogSeverity severity,
                   std::vector<std::string> *outvec);

        // Constructor where we also give a string pointer for storing the
        // message (if the pointer is not NULL).  Implied are: ctr = 0,
        // send_method = &LogMessage::WriteToStringAndLog.
        LogMessage(const char *file, int line, LogSeverity severity,
                   std::string *message);

        // A special constructor used for check failures
        LogMessage(const char *file, int line, const CheckOpString &result);

        ~LogMessage();

        // Flush a buffered message to the sink set in the constructor.  Always
        // called by the destructor, it may also be called from elsewhere if
        // needed.  Only the first call is actioned; any later ones are ignored.
        void Flush();

        // An arbitrary limit on the length of a single log message.  This
        // is so that streaming can be done more efficiently.
        static const size_t kMaxLogMessageLen;

        // Theses should not be called directly outside of logging.*,
        // only passed as SendMethod arguments to other LogMessage methods:
        void SendToLog();          // Actually dispatch to the logs
        void SendToSyslogAndLog(); // Actually dispatch to syslog and the logs

        // Call abort() or similar to perform LOG(FATAL) crash.
        static void __declspec(noreturn) Fail();

        std::ostream &stream();

        int preserved_errno() const;

        // Must be called without the log_mutex held.  (L < log_mutex)
        static int64 num_messages(int severity);

        const LogMessageTime &getLogMessageTime() const;

        struct LogMessageData;

    private:
        // Fully internal SendMethod cases:
        void SendToSinkAndLog(); // Send to sink if provided and dispatch to the logs
        void SendToSink();       // Send to sink if provided, do nothing otherwise.

        // Write to string if provided and dispatch to the logs.
        void WriteToStringAndLog();

        void SaveOrSendToLog(); // Save to stringvec if provided, else to logs

        void Init(const char *file, int line, LogSeverity severity,
                  void (LogMessage::*send_method)());

        // Used to fill in crash information during LOG(FATAL) failures.
        void RecordCrashReason(glog_internal_namespace_::CrashReason *reason);

        // Counts of messages sent at each priority:
        static int64 num_messages_[NUM_SEVERITIES]; // under log_mutex

        // We keep the data in a separate struct so that each instance of
        // LogMessage uses less stack space.
        LogMessageData *allocated_;
        LogMessageData *data_;
        LogMessageTime logmsgtime_;

        friend class LogDestination;

        LogMessage(const LogMessage &);
        void operator=(const LogMessage &);
    };

    // This class happens to be thread-hostile because all instances share
    // a single data buffer, but since it can only be created just before
    // the process dies, we don't worry so much.
    class GLOG_EXPORT LogMessageFatal : public LogMessage
    {
    public:
        LogMessageFatal(const char *file, int line);
        LogMessageFatal(const char *file, int line, const CheckOpString &result);
        __declspec(noreturn) ~LogMessageFatal();
    };

    // A non-macro interface to the log facility; (useful
    // when the logging level is not a compile-time constant).
    inline void LogAtLevel(int const severity, std::string const &msg)
    {
        LogMessage(__FILE__, __LINE__, severity).stream() << msg;
    }

// A macro alternative of LogAtLevel. New code may want to use this
// version since there are two advantages: 1. this version outputs the
// file name and the line number where this macro is put like other
// LOG macros, 2. this macro can be used as C++ stream.
#define LOG_AT_LEVEL(severity) google::LogMessage(__FILE__, __LINE__, severity).stream()

// Check if it's compiled in C++11 mode.
//
// GXX_EXPERIMENTAL_CXX0X is defined by gcc and clang up to at least
// gcc-4.7 and clang-3.1 (2011-12-13).  __cplusplus was defined to 1
// in gcc before 4.7 (Crosstool 16) and clang before 3.1, but is
// defined according to the language version in effect thereafter.
// Microsoft Visual Studio 14 (2015) sets __cplusplus==199711 despite
// reasonably good C++11 support, so we set LANG_CXX for it and
// newer versions (_MSC_VER >= 1900).
#if (defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L || \
     (defined(_MSC_VER) && _MSC_VER >= 1900)) &&                      \
    !defined(__UCLIBCXX_MAJOR__)
    // Helper for CHECK_NOTNULL().
    //
    // In C++11, all cases can be handled by a single function. Since the value
    // category of the argument is preserved (also for rvalue references),
    // member initializer lists like the one below will compile correctly:
    //
    //   Foo()
    //     : x_(CHECK_NOTNULL(MethodReturningUniquePtr())) {}
    template <typename T>
    T CheckNotNull(const char *file, int line, const char *names, T &&t)
    {
        if (t == nullptr)
        {
            LogMessageFatal(file, line, new std::string(names));
        }
        return std::forward<T>(t);
    }

#else

    // A small helper for CHECK_NOTNULL().
    template <typename T>
    T *CheckNotNull(const char *file, int line, const char *names, T *t)
    {
        if (t == NULL)
        {
            LogMessageFatal(file, line, new std::string(names));
        }
        return t;
    }
#endif

    // Allow folks to put a counter in the LOG_EVERY_X()'ed messages. This
    // only works if ostream is a LogStream. If the ostream is not a
    // LogStream you'll get an assert saying as much at runtime.
    GLOG_EXPORT std::ostream &operator<<(std::ostream &os,
                                         const PRIVATE_Counter &);

    // Derived class for PLOG*() above.
    class GLOG_EXPORT ErrnoLogMessage : public LogMessage
    {
    public:
        ErrnoLogMessage(const char *file, int line, LogSeverity severity, int64 ctr,
                        void (LogMessage::*send_method)());

        // Postpends ": strerror(errno) [errno]".
        ~ErrnoLogMessage();

    private:
        ErrnoLogMessage(const ErrnoLogMessage &);
        void operator=(const ErrnoLogMessage &);
    };

    // 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 GLOG_EXPORT LogMessageVoidify
    {
    public:
        LogMessageVoidify() {}
        // This has to be an operator with a precedence lower than << but
        // higher than ?:
        void operator&(std::ostream &) {}
    };

    // Flushes all log files that contains messages that are at least of
    // the specified severity level.  Thread-safe.
    GLOG_EXPORT void FlushLogFiles(LogSeverity min_severity);

    // Flushes all log files that contains messages that are at least of
    // the specified severity level. Thread-hostile because it ignores
    // locking -- used for catastrophic failures.
    GLOG_EXPORT void FlushLogFilesUnsafe(LogSeverity min_severity);

    //
    // Set the destination to which a particular severity level of log
    // messages is sent.  If base_filename is "", it means "don't log this
    // severity".  Thread-safe.
    //
    GLOG_EXPORT void SetLogDestination(LogSeverity severity,
                                       const char *base_filename);

    //
    // Set the basename of the symlink to the latest log file at a given
    // severity.  If symlink_basename is empty, do not make a symlink.  If
    // you don't call this function, the symlink basename is the
    // invocation name of the program.  Thread-safe.
    //
    GLOG_EXPORT void SetLogSymlink(LogSeverity severity,
                                   const char *symlink_basename);

    //
    // Used to send logs to some other kind of destination
    // Users should subclass LogSink and override send to do whatever they want.
    // Implementations must be thread-safe because a shared instance will
    // be called from whichever thread ran the LOG(XXX) line.
    class GLOG_EXPORT LogSink
    {
    public:
        virtual ~LogSink();

        // Sink's logging logic (message_len is such as to exclude '\n' at the end).
        // This method can't use LOG() or CHECK() as logging system mutex(s) are held
        // during this call.
        virtual void send(LogSeverity severity, const char *full_filename,
                          const char *base_filename, int line,
                          const LogMessageTime &logmsgtime, const char *message,
                          size_t message_len);
        // Provide an overload for compatibility purposes
        GLOG_DEPRECATED
        virtual void send(LogSeverity severity, const char *full_filename,
                          const char *base_filename, int line, const std::tm *t,
                          const char *message, size_t message_len);

        // Redefine this to implement waiting for
        // the sink's logging logic to complete.
        // It will be called after each send() returns,
        // but before that LogMessage exits or crashes.
        // By default this function does nothing.
        // Using this function one can implement complex logic for send()
        // that itself involves logging; and do all this w/o causing deadlocks and
        // inconsistent rearrangement of log messages.
        // E.g. if a LogSink has thread-specific actions, the send() method
        // can simply add the message to a queue and wake up another thread that
        // handles real logging while itself making some LOG() calls;
        // WaitTillSent() can be implemented to wait for that logic to complete.
        // See our unittest for an example.
        virtual void WaitTillSent();

        // Returns the normal text output of the log message.
        // Can be useful to implement send().
        static std::string ToString(LogSeverity severity, const char *file, int line,
                                    const LogMessageTime &logmsgtime,
                                    const char *message, size_t message_len);
    };

    // Add or remove a LogSink as a consumer of logging data.  Thread-safe.
    GLOG_EXPORT void AddLogSink(LogSink *destination);
    GLOG_EXPORT void RemoveLogSink(LogSink *destination);

    //
    // Specify an "extension" added to the filename specified via
    // SetLogDestination.  This applies to all severity levels.  It's
    // often used to append the port we're listening on to the logfile
    // name.  Thread-safe.
    //
    GLOG_EXPORT void SetLogFilenameExtension(
        const char *filename_extension);

    //
    // Make it so that all log messages of at least a particular severity
    // are logged to stderr (in addition to logging to the usual log
    // file(s)).  Thread-safe.
    //
    GLOG_EXPORT void SetStderrLogging(LogSeverity min_severity);

    //
    // Make it so that all log messages go only to stderr.  Thread-safe.
    //
    GLOG_EXPORT void LogToStderr();

    //
    // Make it so that all log messages of at least a particular severity are
    // logged via email to a list of addresses (in addition to logging to the
    // usual log file(s)).  The list of addresses is just a string containing
    // the email addresses to send to (separated by spaces, say).  Thread-safe.
    //
    GLOG_EXPORT void SetEmailLogging(LogSeverity min_severity,
                                     const char *addresses);

    // A simple function that sends email. dest is a commma-separated
    // list of addressess.  Thread-safe.
    GLOG_EXPORT bool SendEmail(const char *dest, const char *subject,
                               const char *body);

    GLOG_EXPORT const std::vector<std::string> &GetLoggingDirectories();

    // For tests only:  Clear the internal [cached] list of logging directories to
    // force a refresh the next time GetLoggingDirectories is called.
    // Thread-hostile.
    void TestOnly_ClearLoggingDirectoriesList();

    // Returns a set of existing temporary directories, which will be a
    // subset of the directories returned by GetLoggingDirectories().
    // Thread-safe.
    GLOG_EXPORT void GetExistingTempDirectories(
        std::vector<std::string> *list);

    // Print any fatal message again -- useful to call from signal handler
    // so that the last thing in the output is the fatal message.
    // Thread-hostile, but a race is unlikely.
    GLOG_EXPORT void ReprintFatalMessage();

    // Truncate a log file that may be the append-only output of multiple
    // processes and hence can't simply be renamed/reopened (typically a
    // stdout/stderr).  If the file "path" is > "limit" bytes, copy the
    // last "keep" bytes to offset 0 and truncate the rest. Since we could
    // be racing with other writers, this approach has the potential to
    // lose very small amounts of data. For security, only follow symlinks
    // if the path is /proc/self/fd/*
    GLOG_EXPORT void TruncateLogFile(const char *path, uint64 limit, uint64 keep);

    // Truncate stdout and stderr if they are over the value specified by
    // --max_log_size; keep the final 1MB.  This function has the same
    // race condition as TruncateLogFile.
    GLOG_EXPORT void TruncateStdoutStderr();

    // Return the string representation of the provided LogSeverity level.
    // Thread-safe.
    GLOG_EXPORT const char *GetLogSeverityName(LogSeverity severity);

    // ---------------------------------------------------------------------
    // Implementation details that are not useful to most clients
    // ---------------------------------------------------------------------

    // A Logger is the interface used by logging modules to emit entries
    // to a log.  A typical implementation will dump formatted data to a
    // sequence of files.  We also provide interfaces that will forward
    // the data to another thread so that the invoker never blocks.
    // Implementations should be thread-safe since the logging system
    // will write to them from multiple threads.

    namespace base
    {

        class GLOG_EXPORT Logger
        {
        public:
            virtual ~Logger();

            // Writes "message[0,message_len-1]" corresponding to an event that
            // occurred at "timestamp".  If "force_flush" is true, the log file
            // is flushed immediately.
            //
            // The input message has already been formatted as deemed
            // appropriate by the higher level logging facility.  For example,
            // textual log messages already contain timestamps, and the
            // file:linenumber header.
            virtual void Write(bool force_flush,
                               time_t timestamp,
                               const char *message,
                               size_t message_len) = 0;

            // Flush any buffered messages
            virtual void Flush() = 0;

            // Get the current LOG file size.
            // The returned value is approximate since some
            // logged data may not have been flushed to disk yet.
            virtual uint32 LogSize() = 0;
        };

        // Get the logger for the specified severity level.  The logger
        // remains the property of the logging module and should not be
        // deleted by the caller.  Thread-safe.
        extern GLOG_EXPORT Logger *GetLogger(LogSeverity level);

        // Set the logger for the specified severity level.  The logger
        // becomes the property of the logging module and should not
        // be deleted by the caller.  Thread-safe.
        extern GLOG_EXPORT void SetLogger(LogSeverity level, Logger *logger);

    }

    // glibc has traditionally implemented two incompatible versions of
    // strerror_r(). There is a poorly defined convention for picking the
    // version that we want, but it is not clear whether it even works with
    // all versions of glibc.
    // So, instead, we provide this wrapper that automatically detects the
    // version that is in use, and then implements POSIX semantics.
    // N.B. In addition to what POSIX says, we also guarantee that "buf" will
    // be set to an empty string, if this function failed. This means, in most
    // cases, you do not need to check the error code and you can directly
    // use the value of "buf". It will never have an undefined value.
    // DEPRECATED: Use StrError(int) instead.
    GLOG_EXPORT int posix_strerror_r(int err, char *buf, size_t len);

    // A thread-safe replacement for strerror(). Returns a string describing the
    // given POSIX error code.
    GLOG_EXPORT std::string StrError(int err);

    // A class for which we define operator<<, which does nothing.
    class GLOG_EXPORT NullStream : public LogMessage::LogStream
    {
    public:
        // Initialize the LogStream so the messages can be written somewhere
        // (they'll never be actually displayed). This will be needed if a
        // NullStream& is implicitly converted to LogStream&, in which case
        // the overloaded NullStream::operator<< will not be invoked.
        NullStream() : LogMessage::LogStream(message_buffer_, 1, 0) {}
        NullStream(const char * /*file*/, int /*line*/,
                   const CheckOpString & /*result*/) : LogMessage::LogStream(message_buffer_, 1, 0) {}
        NullStream &stream() { return *this; }

    private:
        // A very short buffer for messages (which we discard anyway). This
        // will be needed if NullStream& converted to LogStream& (e.g. as a
        // result of a conditional expression).
        char message_buffer_[2];
    };

    // Do nothing. This operator is inline, allowing the message to be
    // compiled away. The message will not be compiled away if we do
    // something like (flag ? LOG(INFO) : LOG(ERROR)) << message; when
    // SKIP_LOG=WARNING. In those cases, NullStream will be implicitly
    // converted to LogStream and the message will be computed and then
    // quietly discarded.
    template <class T>
    inline NullStream &operator<<(NullStream &str, const T &) { return str; }

    // Similar to NullStream, but aborts the program (without stack
    // trace), like LogMessageFatal.
    class GLOG_EXPORT NullStreamFatal : public NullStream
    {
    public:
        NullStreamFatal() {}
        NullStreamFatal(const char *file, int line, const CheckOpString &result) : NullStream(file, line, result) {}
#if defined(_MSC_VER)
#pragma warning(push)
#pragma warning(disable : 4722)
#endif // _MSC_VER
        __declspec(noreturn) ~NullStreamFatal() throw()
        {
            _exit(EXIT_FAILURE);
        }
#if defined(_MSC_VER)
#pragma warning(pop)
#endif // _MSC_VER
    };

    // Install a signal handler that will dump signal information and a stack
    // trace when the program crashes on certain signals.  We'll install the
    // signal handler for the following signals.
    //
    // SIGSEGV, SIGILL, SIGFPE, SIGABRT, SIGBUS, and SIGTERM.
    //
    // By default, the signal handler will write the failure dump to the
    // standard error.  You can customize the destination by installing your
    // own writer function by InstallFailureWriter() below.
    //
    // Note on threading:
    //
    // The function should be called before threads are created, if you want
    // to use the failure signal handler for all threads.  The stack trace
    // will be shown only for the thread that receives the signal.  In other
    // words, stack traces of other threads won't be shown.
    GLOG_EXPORT void InstallFailureSignalHandler();

    // Installs a function that is used for writing the failure dump.  "data"
    // is the pointer to the beginning of a message to be written, and "size"
    // is the size of the message.  You should not expect the data is
    // terminated with '\0'.
    GLOG_EXPORT void InstallFailureWriter(
        void (*writer)(const char *data, size_t size));
}

#pragma pop_macro("DECLARE_VARIABLE")
#pragma pop_macro("DECLARE_bool")
#pragma pop_macro("DECLARE_string")
#pragma pop_macro("DECLARE_int32")
#pragma pop_macro("DECLARE_uint32")

#endif // GLOG_LOGGING_H
