1// Copyright (c) 1999, Google Inc.
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met:
7//
8// * Redistributions of source code must retain the above copyright
9// notice, this list of conditions and the following disclaimer.
10// * Redistributions in binary form must reproduce the above
11// copyright notice, this list of conditions and the following disclaimer
12// in the documentation and/or other materials provided with the
13// distribution.
14// * Neither the name of Google Inc. nor the names of its
15// contributors may be used to endorse or promote products derived from
16// this software without specific prior written permission.
17//
18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29//
30// Author: Ray Sidney
31//
32// This file contains #include information about logging-related stuff.
33// Pretty much everybody needs to #include this file so that they can
34// log various happenings.
35//
36#ifndef _LOGGING_H_
37#define _LOGGING_H_
38
39#include <errno.h>
40#include <string.h>
41#include <time.h>
42#include <iosfwd>
43#include <ostream>
44#include <sstream>
45#include <string>
46#if 1
47# include <unistd.h>
48#endif
49#include <vector>
50
51#if defined(_MSC_VER)
52#define GLOG_MSVC_PUSH_DISABLE_WARNING(n) __pragma(warning(push)) \
53 __pragma(warning(disable:n))
54#define GLOG_MSVC_POP_WARNING() __pragma(warning(pop))
55#else
56#define GLOG_MSVC_PUSH_DISABLE_WARNING(n)
57#define GLOG_MSVC_POP_WARNING()
58#endif
59
60// Annoying stuff for windows -- makes sure clients can import these functions
61#ifndef GOOGLE_GLOG_DLL_DECL
62# if defined(_WIN32) && !defined(__CYGWIN__)
63# define GOOGLE_GLOG_DLL_DECL __declspec(dllimport)
64# else
65# define GOOGLE_GLOG_DLL_DECL
66# endif
67#endif
68
69// We care a lot about number of bits things take up. Unfortunately,
70// systems define their bit-specific ints in a lot of different ways.
71// We use our own way, and have a typedef to get there.
72// Note: these commands below may look like "#if 1" or "#if 0", but
73// that's because they were constructed that way at ./configure time.
74// Look at logging.h.in to see how they're calculated (based on your config).
75#if 1
76#include <stdint.h> // the normal place uint16_t is defined
77#endif
78#if 1
79#include <sys/types.h> // the normal place u_int16_t is defined
80#endif
81#if 1
82#include <inttypes.h> // a third place for uint16_t or u_int16_t
83#endif
84
85#if 0
86#include <gflags/gflags.h>
87#endif
88
89namespace google {
90
91#if 1 // the C99 format
92typedef int32_t int32;
93typedef uint32_t uint32;
94typedef int64_t int64;
95typedef uint64_t uint64;
96#elif 1 // the BSD format
97typedef int32_t int32;
98typedef u_int32_t uint32;
99typedef int64_t int64;
100typedef u_int64_t uint64;
101#elif 0 // the windows (vc7) format
102typedef __int32 int32;
103typedef unsigned __int32 uint32;
104typedef __int64 int64;
105typedef unsigned __int64 uint64;
106#else
107#error Do not know how to define a 32-bit integer quantity on your system
108#endif
109
110}
111
112// The global value of GOOGLE_STRIP_LOG. All the messages logged to
113// LOG(XXX) with severity less than GOOGLE_STRIP_LOG will not be displayed.
114// If it can be determined at compile time that the message will not be
115// printed, the statement will be compiled out.
116//
117// Example: to strip out all INFO and WARNING messages, use the value
118// of 2 below. To make an exception for WARNING messages from a single
119// file, add "#define GOOGLE_STRIP_LOG 1" to that file _before_ including
120// base/logging.h
121#ifndef GOOGLE_STRIP_LOG
122#define GOOGLE_STRIP_LOG 0
123#endif
124
125// GCC can be told that a certain branch is not likely to be taken (for
126// instance, a CHECK failure), and use that information in static analysis.
127// Giving it this information can help it optimize for the common case in
128// the absence of better information (ie. -fprofile-arcs).
129//
130#ifndef GOOGLE_PREDICT_BRANCH_NOT_TAKEN
131#if 1
132#define GOOGLE_PREDICT_BRANCH_NOT_TAKEN(x) (__builtin_expect(x, 0))
133#else
134#define GOOGLE_PREDICT_BRANCH_NOT_TAKEN(x) x
135#endif
136#endif
137
138#ifndef GOOGLE_PREDICT_FALSE
139#if 1
140#define GOOGLE_PREDICT_FALSE(x) (__builtin_expect(x, 0))
141#else
142#define GOOGLE_PREDICT_FALSE(x) x
143#endif
144#endif
145
146#ifndef GOOGLE_PREDICT_TRUE
147#if 1
148#define GOOGLE_PREDICT_TRUE(x) (__builtin_expect(!!(x), 1))
149#else
150#define GOOGLE_PREDICT_TRUE(x) x
151#endif
152#endif
153
154
155// Make a bunch of macros for logging. The way to log things is to stream
156// things to LOG(<a particular severity level>). E.g.,
157//
158// LOG(INFO) << "Found " << num_cookies << " cookies";
159//
160// You can capture log messages in a string, rather than reporting them
161// immediately:
162//
163// vector<string> errors;
164// LOG_STRING(ERROR, &errors) << "Couldn't parse cookie #" << cookie_num;
165//
166// This pushes back the new error onto 'errors'; if given a NULL pointer,
167// it reports the error via LOG(ERROR).
168//
169// You can also do conditional logging:
170//
171// LOG_IF(INFO, num_cookies > 10) << "Got lots of cookies";
172//
173// You can also do occasional logging (log every n'th occurrence of an
174// event):
175//
176// LOG_EVERY_N(INFO, 10) << "Got the " << google::COUNTER << "th cookie";
177//
178// The above will cause log messages to be output on the 1st, 11th, 21st, ...
179// times it is executed. Note that the special google::COUNTER value is used
180// to identify which repetition is happening.
181//
182// You can also do occasional conditional logging (log every n'th
183// occurrence of an event, when condition is satisfied):
184//
185// LOG_IF_EVERY_N(INFO, (size > 1024), 10) << "Got the " << google::COUNTER
186// << "th big cookie";
187//
188// You can log messages the first N times your code executes a line. E.g.
189//
190// LOG_FIRST_N(INFO, 20) << "Got the " << google::COUNTER << "th cookie";
191//
192// Outputs log messages for the first 20 times it is executed.
193//
194// Analogous SYSLOG, SYSLOG_IF, and SYSLOG_EVERY_N macros are available.
195// These log to syslog as well as to the normal logs. If you use these at
196// all, you need to be aware that syslog can drastically reduce performance,
197// especially if it is configured for remote logging! Don't use these
198// unless you fully understand this and have a concrete need to use them.
199// Even then, try to minimize your use of them.
200//
201// There are also "debug mode" logging macros like the ones above:
202//
203// DLOG(INFO) << "Found cookies";
204//
205// DLOG_IF(INFO, num_cookies > 10) << "Got lots of cookies";
206//
207// DLOG_EVERY_N(INFO, 10) << "Got the " << google::COUNTER << "th cookie";
208//
209// All "debug mode" logging is compiled away to nothing for non-debug mode
210// compiles.
211//
212// We also have
213//
214// LOG_ASSERT(assertion);
215// DLOG_ASSERT(assertion);
216//
217// which is syntactic sugar for {,D}LOG_IF(FATAL, assert fails) << assertion;
218//
219// There are "verbose level" logging macros. They look like
220//
221// VLOG(1) << "I'm printed when you run the program with --v=1 or more";
222// VLOG(2) << "I'm printed when you run the program with --v=2 or more";
223//
224// These always log at the INFO log level (when they log at all).
225// The verbose logging can also be turned on module-by-module. For instance,
226// --vmodule=mapreduce=2,file=1,gfs*=3 --v=0
227// will cause:
228// a. VLOG(2) and lower messages to be printed from mapreduce.{h,cc}
229// b. VLOG(1) and lower messages to be printed from file.{h,cc}
230// c. VLOG(3) and lower messages to be printed from files prefixed with "gfs"
231// d. VLOG(0) and lower messages to be printed from elsewhere
232//
233// The wildcarding functionality shown by (c) supports both '*' (match
234// 0 or more characters) and '?' (match any single character) wildcards.
235//
236// There's also VLOG_IS_ON(n) "verbose level" condition macro. To be used as
237//
238// if (VLOG_IS_ON(2)) {
239// // do some logging preparation and logging
240// // that can't be accomplished with just VLOG(2) << ...;
241// }
242//
243// There are also VLOG_IF, VLOG_EVERY_N and VLOG_IF_EVERY_N "verbose level"
244// condition macros for sample cases, when some extra computation and
245// preparation for logs is not needed.
246// VLOG_IF(1, (size > 1024))
247// << "I'm printed when size is more than 1024 and when you run the "
248// "program with --v=1 or more";
249// VLOG_EVERY_N(1, 10)
250// << "I'm printed every 10th occurrence, and when you run the program "
251// "with --v=1 or more. Present occurence is " << google::COUNTER;
252// VLOG_IF_EVERY_N(1, (size > 1024), 10)
253// << "I'm printed on every 10th occurence of case when size is more "
254// " than 1024, when you run the program with --v=1 or more. ";
255// "Present occurence is " << google::COUNTER;
256//
257// The supported severity levels for macros that allow you to specify one
258// are (in increasing order of severity) INFO, WARNING, ERROR, and FATAL.
259// Note that messages of a given severity are logged not only in the
260// logfile for that severity, but also in all logfiles of lower severity.
261// E.g., a message of severity FATAL will be logged to the logfiles of
262// severity FATAL, ERROR, WARNING, and INFO.
263//
264// There is also the special severity of DFATAL, which logs FATAL in
265// debug mode, ERROR in normal mode.
266//
267// Very important: logging a message at the FATAL severity level causes
268// the program to terminate (after the message is logged).
269//
270// Unless otherwise specified, logs will be written to the filename
271// "<program name>.<hostname>.<user name>.log.<severity level>.", followed
272// by the date, time, and pid (you can't prevent the date, time, and pid
273// from being in the filename).
274//
275// The logging code takes two flags:
276// --v=# set the verbose level
277// --logtostderr log all the messages to stderr instead of to logfiles
278
279// LOG LINE PREFIX FORMAT
280//
281// Log lines have this form:
282//
283// Lmmdd hh:mm:ss.uuuuuu threadid file:line] msg...
284//
285// where the fields are defined as follows:
286//
287// L A single character, representing the log level
288// (eg 'I' for INFO)
289// mm The month (zero padded; ie May is '05')
290// dd The day (zero padded)
291// hh:mm:ss.uuuuuu Time in hours, minutes and fractional seconds
292// threadid The space-padded thread ID as returned by GetTID()
293// (this matches the PID on Linux)
294// file The file name
295// line The line number
296// msg The user-supplied message
297//
298// Example:
299//
300// I1103 11:57:31.739339 24395 google.cc:2341] Command line: ./some_prog
301// I1103 11:57:31.739403 24395 google.cc:2342] Process id 24395
302//
303// NOTE: although the microseconds are useful for comparing events on
304// a single machine, clocks on different machines may not be well
305// synchronized. Hence, use caution when comparing the low bits of
306// timestamps from different machines.
307
308#ifndef DECLARE_VARIABLE
309#define MUST_UNDEF_GFLAGS_DECLARE_MACROS
310#define DECLARE_VARIABLE(type, shorttype, name, tn) \
311 namespace fL##shorttype { \
312 extern GOOGLE_GLOG_DLL_DECL type FLAGS_##name; \
313 } \
314 using fL##shorttype::FLAGS_##name
315
316// bool specialization
317#define DECLARE_bool(name) \
318 DECLARE_VARIABLE(bool, B, name, bool)
319
320// int32 specialization
321#define DECLARE_int32(name) \
322 DECLARE_VARIABLE(google::int32, I, name, int32)
323
324// Special case for string, because we have to specify the namespace
325// std::string, which doesn't play nicely with our FLAG__namespace hackery.
326#define DECLARE_string(name) \
327 namespace fLS { \
328 extern GOOGLE_GLOG_DLL_DECL std::string& FLAGS_##name; \
329 } \
330 using fLS::FLAGS_##name
331#endif
332
333// Set whether log messages go to stderr instead of logfiles
334DECLARE_bool(logtostderr);
335
336// Set whether log messages go to stderr in addition to logfiles.
337DECLARE_bool(alsologtostderr);
338
339// Set color messages logged to stderr (if supported by terminal).
340DECLARE_bool(colorlogtostderr);
341
342// Log messages at a level >= this flag are automatically sent to
343// stderr in addition to log files.
344DECLARE_int32(stderrthreshold);
345
346// Set whether the log prefix should be prepended to each line of output.
347DECLARE_bool(log_prefix);
348
349// Log messages at a level <= this flag are buffered.
350// Log messages at a higher level are flushed immediately.
351DECLARE_int32(logbuflevel);
352
353// Sets the maximum number of seconds which logs may be buffered for.
354DECLARE_int32(logbufsecs);
355
356// Log suppression level: messages logged at a lower level than this
357// are suppressed.
358DECLARE_int32(minloglevel);
359
360// If specified, logfiles are written into this directory instead of the
361// default logging directory.
362DECLARE_string(log_dir);
363
364// Set the log file mode.
365DECLARE_int32(logfile_mode);
366
367// Sets the path of the directory into which to put additional links
368// to the log files.
369DECLARE_string(log_link);
370
371DECLARE_int32(v); // in vlog_is_on.cc
372
373// Sets the maximum log file size (in MB).
374DECLARE_int32(max_log_size);
375
376// Sets whether to avoid logging to the disk if the disk is full.
377DECLARE_bool(stop_logging_if_full_disk);
378
379#ifdef MUST_UNDEF_GFLAGS_DECLARE_MACROS
380#undef MUST_UNDEF_GFLAGS_DECLARE_MACROS
381#undef DECLARE_VARIABLE
382#undef DECLARE_bool
383#undef DECLARE_int32
384#undef DECLARE_string
385#endif
386
387// Log messages below the GOOGLE_STRIP_LOG level will be compiled away for
388// security reasons. See LOG(severtiy) below.
389
390// A few definitions of macros that don't generate much code. Since
391// LOG(INFO) and its ilk are used all over our code, it's
392// better to have compact code for these operations.
393
394#if GOOGLE_STRIP_LOG == 0
395#define COMPACT_GOOGLE_LOG_INFO google::LogMessage( \
396 __FILE__, __LINE__)
397#define LOG_TO_STRING_INFO(message) google::LogMessage( \
398 __FILE__, __LINE__, google::GLOG_INFO, message)
399#else
400#define COMPACT_GOOGLE_LOG_INFO google::NullStream()
401#define LOG_TO_STRING_INFO(message) google::NullStream()
402#endif
403
404#if GOOGLE_STRIP_LOG <= 1
405#define COMPACT_GOOGLE_LOG_WARNING google::LogMessage( \
406 __FILE__, __LINE__, google::GLOG_WARNING)
407#define LOG_TO_STRING_WARNING(message) google::LogMessage( \
408 __FILE__, __LINE__, google::GLOG_WARNING, message)
409#else
410#define COMPACT_GOOGLE_LOG_WARNING google::NullStream()
411#define LOG_TO_STRING_WARNING(message) google::NullStream()
412#endif
413
414#if GOOGLE_STRIP_LOG <= 2
415#define COMPACT_GOOGLE_LOG_ERROR google::LogMessage( \
416 __FILE__, __LINE__, google::GLOG_ERROR)
417#define LOG_TO_STRING_ERROR(message) google::LogMessage( \
418 __FILE__, __LINE__, google::GLOG_ERROR, message)
419#else
420#define COMPACT_GOOGLE_LOG_ERROR google::NullStream()
421#define LOG_TO_STRING_ERROR(message) google::NullStream()
422#endif
423
424#if GOOGLE_STRIP_LOG <= 3
425#define COMPACT_GOOGLE_LOG_FATAL google::LogMessageFatal( \
426 __FILE__, __LINE__)
427#define LOG_TO_STRING_FATAL(message) google::LogMessage( \
428 __FILE__, __LINE__, google::GLOG_FATAL, message)
429#else
430#define COMPACT_GOOGLE_LOG_FATAL google::NullStreamFatal()
431#define LOG_TO_STRING_FATAL(message) google::NullStreamFatal()
432#endif
433
434#if defined(NDEBUG) && !defined(DCHECK_ALWAYS_ON)
435#define DCHECK_IS_ON() 0
436#else
437#define DCHECK_IS_ON() 1
438#endif
439
440// For DFATAL, we want to use LogMessage (as opposed to
441// LogMessageFatal), to be consistent with the original behavior.
442#if !DCHECK_IS_ON()
443#define COMPACT_GOOGLE_LOG_DFATAL COMPACT_GOOGLE_LOG_ERROR
444#elif GOOGLE_STRIP_LOG <= 3
445#define COMPACT_GOOGLE_LOG_DFATAL google::LogMessage( \
446 __FILE__, __LINE__, google::GLOG_FATAL)
447#else
448#define COMPACT_GOOGLE_LOG_DFATAL google::NullStreamFatal()
449#endif
450
451#define GOOGLE_LOG_INFO(counter) google::LogMessage(__FILE__, __LINE__, google::GLOG_INFO, counter, &google::LogMessage::SendToLog)
452#define SYSLOG_INFO(counter) \
453 google::LogMessage(__FILE__, __LINE__, google::GLOG_INFO, counter, \
454 &google::LogMessage::SendToSyslogAndLog)
455#define GOOGLE_LOG_WARNING(counter) \
456 google::LogMessage(__FILE__, __LINE__, google::GLOG_WARNING, counter, \
457 &google::LogMessage::SendToLog)
458#define SYSLOG_WARNING(counter) \
459 google::LogMessage(__FILE__, __LINE__, google::GLOG_WARNING, counter, \
460 &google::LogMessage::SendToSyslogAndLog)
461#define GOOGLE_LOG_ERROR(counter) \
462 google::LogMessage(__FILE__, __LINE__, google::GLOG_ERROR, counter, \
463 &google::LogMessage::SendToLog)
464#define SYSLOG_ERROR(counter) \
465 google::LogMessage(__FILE__, __LINE__, google::GLOG_ERROR, counter, \
466 &google::LogMessage::SendToSyslogAndLog)
467#define GOOGLE_LOG_FATAL(counter) \
468 google::LogMessage(__FILE__, __LINE__, google::GLOG_FATAL, counter, \
469 &google::LogMessage::SendToLog)
470#define SYSLOG_FATAL(counter) \
471 google::LogMessage(__FILE__, __LINE__, google::GLOG_FATAL, counter, \
472 &google::LogMessage::SendToSyslogAndLog)
473#define GOOGLE_LOG_DFATAL(counter) \
474 google::LogMessage(__FILE__, __LINE__, google::DFATAL_LEVEL, counter, \
475 &google::LogMessage::SendToLog)
476#define SYSLOG_DFATAL(counter) \
477 google::LogMessage(__FILE__, __LINE__, google::DFATAL_LEVEL, counter, \
478 &google::LogMessage::SendToSyslogAndLog)
479
480#if defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__) || defined(__CYGWIN32__)
481// A very useful logging macro to log windows errors:
482#define LOG_SYSRESULT(result) \
483 if (FAILED(HRESULT_FROM_WIN32(result))) { \
484 LPSTR message = NULL; \
485 LPSTR msg = reinterpret_cast<LPSTR>(&message); \
486 DWORD message_length = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | \
487 FORMAT_MESSAGE_FROM_SYSTEM, \
488 0, result, 0, msg, 100, NULL); \
489 if (message_length > 0) { \
490 google::LogMessage(__FILE__, __LINE__, google::GLOG_ERROR, 0, \
491 &google::LogMessage::SendToLog).stream() \
492 << reinterpret_cast<const char*>(message); \
493 LocalFree(message); \
494 } \
495 }
496#endif
497
498// We use the preprocessor's merging operator, "##", so that, e.g.,
499// LOG(INFO) becomes the token GOOGLE_LOG_INFO. There's some funny
500// subtle difference between ostream member streaming functions (e.g.,
501// ostream::operator<<(int) and ostream non-member streaming functions
502// (e.g., ::operator<<(ostream&, string&): it turns out that it's
503// impossible to stream something like a string directly to an unnamed
504// ostream. We employ a neat hack by calling the stream() member
505// function of LogMessage which seems to avoid the problem.
506#define LOG(severity) COMPACT_GOOGLE_LOG_ ## severity.stream()
507#define SYSLOG(severity) SYSLOG_ ## severity(0).stream()
508
509namespace google {
510
511// They need the definitions of integer types.
512#include "glog/log_severity.h"
513#include "glog/vlog_is_on.h"
514
515// Initialize google's logging library. You will see the program name
516// specified by argv0 in log outputs.
517GOOGLE_GLOG_DLL_DECL void InitGoogleLogging(const char* argv0);
518
519// Shutdown google's logging library.
520GOOGLE_GLOG_DLL_DECL void ShutdownGoogleLogging();
521
522// Install a function which will be called after LOG(FATAL).
523GOOGLE_GLOG_DLL_DECL void InstallFailureFunction(void (*fail_func)());
524
525class LogSink; // defined below
526
527// If a non-NULL sink pointer is given, we push this message to that sink.
528// For LOG_TO_SINK we then do normal LOG(severity) logging as well.
529// This is useful for capturing messages and passing/storing them
530// somewhere more specific than the global log of the process.
531// Argument types:
532// LogSink* sink;
533// LogSeverity severity;
534// The cast is to disambiguate NULL arguments.
535#define LOG_TO_SINK(sink, severity) \
536 google::LogMessage( \
537 __FILE__, __LINE__, \
538 google::GLOG_ ## severity, \
539 static_cast<google::LogSink*>(sink), true).stream()
540#define LOG_TO_SINK_BUT_NOT_TO_LOGFILE(sink, severity) \
541 google::LogMessage( \
542 __FILE__, __LINE__, \
543 google::GLOG_ ## severity, \
544 static_cast<google::LogSink*>(sink), false).stream()
545
546// If a non-NULL string pointer is given, we write this message to that string.
547// We then do normal LOG(severity) logging as well.
548// This is useful for capturing messages and storing them somewhere more
549// specific than the global log of the process.
550// Argument types:
551// string* message;
552// LogSeverity severity;
553// The cast is to disambiguate NULL arguments.
554// NOTE: LOG(severity) expands to LogMessage().stream() for the specified
555// severity.
556#define LOG_TO_STRING(severity, message) \
557 LOG_TO_STRING_##severity(static_cast<string*>(message)).stream()
558
559// If a non-NULL pointer is given, we push the message onto the end
560// of a vector of strings; otherwise, we report it with LOG(severity).
561// This is handy for capturing messages and perhaps passing them back
562// to the caller, rather than reporting them immediately.
563// Argument types:
564// LogSeverity severity;
565// vector<string> *outvec;
566// The cast is to disambiguate NULL arguments.
567#define LOG_STRING(severity, outvec) \
568 LOG_TO_STRING_##severity(static_cast<std::vector<std::string>*>(outvec)).stream()
569
570#define LOG_IF(severity, condition) \
571 !(condition) ? (void) 0 : google::LogMessageVoidify() & LOG(severity)
572#define SYSLOG_IF(severity, condition) \
573 !(condition) ? (void) 0 : google::LogMessageVoidify() & SYSLOG(severity)
574
575#define LOG_ASSERT(condition) \
576 LOG_IF(FATAL, !(condition)) << "Assert failed: " #condition
577#define SYSLOG_ASSERT(condition) \
578 SYSLOG_IF(FATAL, !(condition)) << "Assert failed: " #condition
579
580// CHECK dies with a fatal error if condition is not true. It is *not*
581// controlled by DCHECK_IS_ON(), so the check will be executed regardless of
582// compilation mode. Therefore, it is safe to do things like:
583// CHECK(fp->Write(x) == 4)
584#define CHECK(condition) \
585 LOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN(!(condition))) \
586 << "Check failed: " #condition " "
587
588// A container for a string pointer which can be evaluated to a bool -
589// true iff the pointer is NULL.
590struct CheckOpString {
591 CheckOpString(std::string* str) : str_(str) { }
592 // No destructor: if str_ is non-NULL, we're about to LOG(FATAL),
593 // so there's no point in cleaning up str_.
594 operator bool() const {
595 return GOOGLE_PREDICT_BRANCH_NOT_TAKEN(str_ != NULL);
596 }
597 std::string* str_;
598};
599
600// Function is overloaded for integral types to allow static const
601// integrals declared in classes and not defined to be used as arguments to
602// CHECK* macros. It's not encouraged though.
603template <class T>
604inline const T& GetReferenceableValue(const T& t) { return t; }
605inline char GetReferenceableValue(char t) { return t; }
606inline unsigned char GetReferenceableValue(unsigned char t) { return t; }
607inline signed char GetReferenceableValue(signed char t) { return t; }
608inline short GetReferenceableValue(short t) { return t; }
609inline unsigned short GetReferenceableValue(unsigned short t) { return t; }
610inline int GetReferenceableValue(int t) { return t; }
611inline unsigned int GetReferenceableValue(unsigned int t) { return t; }
612inline long GetReferenceableValue(long t) { return t; }
613inline unsigned long GetReferenceableValue(unsigned long t) { return t; }
614inline long long GetReferenceableValue(long long t) { return t; }
615inline unsigned long long GetReferenceableValue(unsigned long long t) {
616 return t;
617}
618
619// This is a dummy class to define the following operator.
620struct DummyClassToDefineOperator {};
621
622}
623
624// Define global operator<< to declare using ::operator<<.
625// This declaration will allow use to use CHECK macros for user
626// defined classes which have operator<< (e.g., stl_logging.h).
627inline std::ostream& operator<<(
628 std::ostream& out, const google::DummyClassToDefineOperator&) {
629 return out;
630}
631
632namespace google {
633
634// This formats a value for a failing CHECK_XX statement. Ordinarily,
635// it uses the definition for operator<<, with a few special cases below.
636template <typename T>
637inline void MakeCheckOpValueString(std::ostream* os, const T& v) {
638 (*os) << v;
639}
640
641// Overrides for char types provide readable values for unprintable
642// characters.
643template <> GOOGLE_GLOG_DLL_DECL
644void MakeCheckOpValueString(std::ostream* os, const char& v);
645template <> GOOGLE_GLOG_DLL_DECL
646void MakeCheckOpValueString(std::ostream* os, const signed char& v);
647template <> GOOGLE_GLOG_DLL_DECL
648void MakeCheckOpValueString(std::ostream* os, const unsigned char& v);
649
650// Build the error message string. Specify no inlining for code size.
651template <typename T1, typename T2>
652std::string* MakeCheckOpString(const T1& v1, const T2& v2, const char* exprtext)
653 __attribute__((noinline));
654
655namespace base {
656namespace internal {
657
658// If "s" is less than base_logging::INFO, returns base_logging::INFO.
659// If "s" is greater than base_logging::FATAL, returns
660// base_logging::ERROR. Otherwise, returns "s".
661LogSeverity NormalizeSeverity(LogSeverity s);
662
663} // namespace internal
664
665// A helper class for formatting "expr (V1 vs. V2)" in a CHECK_XX
666// statement. See MakeCheckOpString for sample usage. Other
667// approaches were considered: use of a template method (e.g.,
668// base::BuildCheckOpString(exprtext, base::Print<T1>, &v1,
669// base::Print<T2>, &v2), however this approach has complications
670// related to volatile arguments and function-pointer arguments).
671class GOOGLE_GLOG_DLL_DECL CheckOpMessageBuilder {
672 public:
673 // Inserts "exprtext" and " (" to the stream.
674 explicit CheckOpMessageBuilder(const char *exprtext);
675 // Deletes "stream_".
676 ~CheckOpMessageBuilder();
677 // For inserting the first variable.
678 std::ostream* ForVar1() { return stream_; }
679 // For inserting the second variable (adds an intermediate " vs. ").
680 std::ostream* ForVar2();
681 // Get the result (inserts the closing ")").
682 std::string* NewString();
683
684 private:
685 std::ostringstream *stream_;
686};
687
688} // namespace base
689
690template <typename T1, typename T2>
691std::string* MakeCheckOpString(const T1& v1, const T2& v2, const char* exprtext) {
692 base::CheckOpMessageBuilder comb(exprtext);
693 MakeCheckOpValueString(comb.ForVar1(), v1);
694 MakeCheckOpValueString(comb.ForVar2(), v2);
695 return comb.NewString();
696}
697
698// Helper functions for CHECK_OP macro.
699// The (int, int) specialization works around the issue that the compiler
700// will not instantiate the template version of the function on values of
701// unnamed enum type - see comment below.
702#define DEFINE_CHECK_OP_IMPL(name, op) \
703 template <typename T1, typename T2> \
704 inline std::string* name##Impl(const T1& v1, const T2& v2, \
705 const char* exprtext) { \
706 if (GOOGLE_PREDICT_TRUE(v1 op v2)) return NULL; \
707 else return MakeCheckOpString(v1, v2, exprtext); \
708 } \
709 inline std::string* name##Impl(int v1, int v2, const char* exprtext) { \
710 return name##Impl<int, int>(v1, v2, exprtext); \
711 }
712
713// We use the full name Check_EQ, Check_NE, etc. in case the file including
714// base/logging.h provides its own #defines for the simpler names EQ, NE, etc.
715// This happens if, for example, those are used as token names in a
716// yacc grammar.
717DEFINE_CHECK_OP_IMPL(Check_EQ, ==) // Compilation error with CHECK_EQ(NULL, x)?
718DEFINE_CHECK_OP_IMPL(Check_NE, !=) // Use CHECK(x == NULL) instead.
719DEFINE_CHECK_OP_IMPL(Check_LE, <=)
720DEFINE_CHECK_OP_IMPL(Check_LT, < )
721DEFINE_CHECK_OP_IMPL(Check_GE, >=)
722DEFINE_CHECK_OP_IMPL(Check_GT, > )
723#undef DEFINE_CHECK_OP_IMPL
724
725// Helper macro for binary operators.
726// Don't use this macro directly in your code, use CHECK_EQ et al below.
727
728#if defined(STATIC_ANALYSIS)
729// Only for static analysis tool to know that it is equivalent to assert
730#define CHECK_OP_LOG(name, op, val1, val2, log) CHECK((val1) op (val2))
731#elif DCHECK_IS_ON()
732// In debug mode, avoid constructing CheckOpStrings if possible,
733// to reduce the overhead of CHECK statments by 2x.
734// Real DCHECK-heavy tests have seen 1.5x speedups.
735
736// The meaning of "string" might be different between now and
737// when this macro gets invoked (e.g., if someone is experimenting
738// with other string implementations that get defined after this
739// file is included). Save the current meaning now and use it
740// in the macro.
741typedef std::string _Check_string;
742#define CHECK_OP_LOG(name, op, val1, val2, log) \
743 while (google::_Check_string* _result = \
744 google::Check##name##Impl( \
745 google::GetReferenceableValue(val1), \
746 google::GetReferenceableValue(val2), \
747 #val1 " " #op " " #val2)) \
748 log(__FILE__, __LINE__, \
749 google::CheckOpString(_result)).stream()
750#else
751// In optimized mode, use CheckOpString to hint to compiler that
752// the while condition is unlikely.
753#define CHECK_OP_LOG(name, op, val1, val2, log) \
754 while (google::CheckOpString _result = \
755 google::Check##name##Impl( \
756 google::GetReferenceableValue(val1), \
757 google::GetReferenceableValue(val2), \
758 #val1 " " #op " " #val2)) \
759 log(__FILE__, __LINE__, _result).stream()
760#endif // STATIC_ANALYSIS, DCHECK_IS_ON()
761
762#if GOOGLE_STRIP_LOG <= 3
763#define CHECK_OP(name, op, val1, val2) \
764 CHECK_OP_LOG(name, op, val1, val2, google::LogMessageFatal)
765#else
766#define CHECK_OP(name, op, val1, val2) \
767 CHECK_OP_LOG(name, op, val1, val2, google::NullStreamFatal)
768#endif // STRIP_LOG <= 3
769
770// Equality/Inequality checks - compare two values, and log a FATAL message
771// including the two values when the result is not as expected. The values
772// must have operator<<(ostream, ...) defined.
773//
774// You may append to the error message like so:
775// CHECK_NE(1, 2) << ": The world must be ending!";
776//
777// We are very careful to ensure that each argument is evaluated exactly
778// once, and that anything which is legal to pass as a function argument is
779// legal here. In particular, the arguments may be temporary expressions
780// which will end up being destroyed at the end of the apparent statement,
781// for example:
782// CHECK_EQ(string("abc")[1], 'b');
783//
784// WARNING: These don't compile correctly if one of the arguments is a pointer
785// and the other is NULL. To work around this, simply static_cast NULL to the
786// type of the desired pointer.
787
788#define CHECK_EQ(val1, val2) CHECK_OP(_EQ, ==, val1, val2)
789#define CHECK_NE(val1, val2) CHECK_OP(_NE, !=, val1, val2)
790#define CHECK_LE(val1, val2) CHECK_OP(_LE, <=, val1, val2)
791#define CHECK_LT(val1, val2) CHECK_OP(_LT, < , val1, val2)
792#define CHECK_GE(val1, val2) CHECK_OP(_GE, >=, val1, val2)
793#define CHECK_GT(val1, val2) CHECK_OP(_GT, > , val1, val2)
794
795// Check that the input is non NULL. This very useful in constructor
796// initializer lists.
797
798#define CHECK_NOTNULL(val) \
799 google::CheckNotNull(__FILE__, __LINE__, "'" #val "' Must be non NULL", (val))
800
801// Helper functions for string comparisons.
802// To avoid bloat, the definitions are in logging.cc.
803#define DECLARE_CHECK_STROP_IMPL(func, expected) \
804 GOOGLE_GLOG_DLL_DECL std::string* Check##func##expected##Impl( \
805 const char* s1, const char* s2, const char* names);
806DECLARE_CHECK_STROP_IMPL(strcmp, true)
807DECLARE_CHECK_STROP_IMPL(strcmp, false)
808DECLARE_CHECK_STROP_IMPL(strcasecmp, true)
809DECLARE_CHECK_STROP_IMPL(strcasecmp, false)
810#undef DECLARE_CHECK_STROP_IMPL
811
812// Helper macro for string comparisons.
813// Don't use this macro directly in your code, use CHECK_STREQ et al below.
814#define CHECK_STROP(func, op, expected, s1, s2) \
815 while (google::CheckOpString _result = \
816 google::Check##func##expected##Impl((s1), (s2), \
817 #s1 " " #op " " #s2)) \
818 LOG(FATAL) << *_result.str_
819
820
821// String (char*) equality/inequality checks.
822// CASE versions are case-insensitive.
823//
824// Note that "s1" and "s2" may be temporary strings which are destroyed
825// by the compiler at the end of the current "full expression"
826// (e.g. CHECK_STREQ(Foo().c_str(), Bar().c_str())).
827
828#define CHECK_STREQ(s1, s2) CHECK_STROP(strcmp, ==, true, s1, s2)
829#define CHECK_STRNE(s1, s2) CHECK_STROP(strcmp, !=, false, s1, s2)
830#define CHECK_STRCASEEQ(s1, s2) CHECK_STROP(strcasecmp, ==, true, s1, s2)
831#define CHECK_STRCASENE(s1, s2) CHECK_STROP(strcasecmp, !=, false, s1, s2)
832
833#define CHECK_INDEX(I,A) CHECK(I < (sizeof(A)/sizeof(A[0])))
834#define CHECK_BOUND(B,A) CHECK(B <= (sizeof(A)/sizeof(A[0])))
835
836#define CHECK_DOUBLE_EQ(val1, val2) \
837 do { \
838 CHECK_LE((val1), (val2)+0.000000000000001L); \
839 CHECK_GE((val1), (val2)-0.000000000000001L); \
840 } while (0)
841
842#define CHECK_NEAR(val1, val2, margin) \
843 do { \
844 CHECK_LE((val1), (val2)+(margin)); \
845 CHECK_GE((val1), (val2)-(margin)); \
846 } while (0)
847
848// perror()..googly style!
849//
850// PLOG() and PLOG_IF() and PCHECK() behave exactly like their LOG* and
851// CHECK equivalents with the addition that they postpend a description
852// of the current state of errno to their output lines.
853
854#define PLOG(severity) GOOGLE_PLOG(severity, 0).stream()
855
856#define GOOGLE_PLOG(severity, counter) \
857 google::ErrnoLogMessage( \
858 __FILE__, __LINE__, google::GLOG_ ## severity, counter, \
859 &google::LogMessage::SendToLog)
860
861#define PLOG_IF(severity, condition) \
862 !(condition) ? (void) 0 : google::LogMessageVoidify() & PLOG(severity)
863
864// A CHECK() macro that postpends errno if the condition is false. E.g.
865//
866// if (poll(fds, nfds, timeout) == -1) { PCHECK(errno == EINTR); ... }
867#define PCHECK(condition) \
868 PLOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN(!(condition))) \
869 << "Check failed: " #condition " "
870
871// A CHECK() macro that lets you assert the success of a function that
872// returns -1 and sets errno in case of an error. E.g.
873//
874// CHECK_ERR(mkdir(path, 0700));
875//
876// or
877//
878// int fd = open(filename, flags); CHECK_ERR(fd) << ": open " << filename;
879#define CHECK_ERR(invocation) \
880PLOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN((invocation) == -1)) \
881 << #invocation
882
883// Use macro expansion to create, for each use of LOG_EVERY_N(), static
884// variables with the __LINE__ expansion as part of the variable name.
885#define LOG_EVERY_N_VARNAME(base, line) LOG_EVERY_N_VARNAME_CONCAT(base, line)
886#define LOG_EVERY_N_VARNAME_CONCAT(base, line) base ## line
887
888#define LOG_OCCURRENCES LOG_EVERY_N_VARNAME(occurrences_, __LINE__)
889#define LOG_OCCURRENCES_MOD_N LOG_EVERY_N_VARNAME(occurrences_mod_n_, __LINE__)
890
891#define SOME_KIND_OF_LOG_EVERY_N(severity, n, what_to_do) \
892 static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0; \
893 ++LOG_OCCURRENCES; \
894 if (++LOG_OCCURRENCES_MOD_N > n) LOG_OCCURRENCES_MOD_N -= n; \
895 if (LOG_OCCURRENCES_MOD_N == 1) \
896 google::LogMessage( \
897 __FILE__, __LINE__, google::GLOG_ ## severity, LOG_OCCURRENCES, \
898 &what_to_do).stream()
899
900#define SOME_KIND_OF_LOG_IF_EVERY_N(severity, condition, n, what_to_do) \
901 static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0; \
902 ++LOG_OCCURRENCES; \
903 if (condition && \
904 ((LOG_OCCURRENCES_MOD_N=(LOG_OCCURRENCES_MOD_N + 1) % n) == (1 % n))) \
905 google::LogMessage( \
906 __FILE__, __LINE__, google::GLOG_ ## severity, LOG_OCCURRENCES, \
907 &what_to_do).stream()
908
909#define SOME_KIND_OF_PLOG_EVERY_N(severity, n, what_to_do) \
910 static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0; \
911 ++LOG_OCCURRENCES; \
912 if (++LOG_OCCURRENCES_MOD_N > n) LOG_OCCURRENCES_MOD_N -= n; \
913 if (LOG_OCCURRENCES_MOD_N == 1) \
914 google::ErrnoLogMessage( \
915 __FILE__, __LINE__, google::GLOG_ ## severity, LOG_OCCURRENCES, \
916 &what_to_do).stream()
917
918#define SOME_KIND_OF_LOG_FIRST_N(severity, n, what_to_do) \
919 static int LOG_OCCURRENCES = 0; \
920 if (LOG_OCCURRENCES <= n) \
921 ++LOG_OCCURRENCES; \
922 if (LOG_OCCURRENCES <= n) \
923 google::LogMessage( \
924 __FILE__, __LINE__, google::GLOG_ ## severity, LOG_OCCURRENCES, \
925 &what_to_do).stream()
926
927namespace glog_internal_namespace_ {
928template <bool>
929struct CompileAssert {
930};
931struct CrashReason;
932
933// Returns true if FailureSignalHandler is installed.
934bool IsFailureSignalHandlerInstalled();
935} // namespace glog_internal_namespace_
936
937#define GOOGLE_GLOG_COMPILE_ASSERT(expr, msg) \
938 typedef google::glog_internal_namespace_::CompileAssert<(bool(expr))> msg[bool(expr) ? 1 : -1]
939
940#define LOG_EVERY_N(severity, n) \
941 GOOGLE_GLOG_COMPILE_ASSERT(google::GLOG_ ## severity < \
942 google::NUM_SEVERITIES, \
943 INVALID_REQUESTED_LOG_SEVERITY); \
944 SOME_KIND_OF_LOG_EVERY_N(severity, (n), google::LogMessage::SendToLog)
945
946#define SYSLOG_EVERY_N(severity, n) \
947 SOME_KIND_OF_LOG_EVERY_N(severity, (n), google::LogMessage::SendToSyslogAndLog)
948
949#define PLOG_EVERY_N(severity, n) \
950 SOME_KIND_OF_PLOG_EVERY_N(severity, (n), google::LogMessage::SendToLog)
951
952#define LOG_FIRST_N(severity, n) \
953 SOME_KIND_OF_LOG_FIRST_N(severity, (n), google::LogMessage::SendToLog)
954
955#define LOG_IF_EVERY_N(severity, condition, n) \
956 SOME_KIND_OF_LOG_IF_EVERY_N(severity, (condition), (n), google::LogMessage::SendToLog)
957
958// We want the special COUNTER value available for LOG_EVERY_X()'ed messages
959enum PRIVATE_Counter {COUNTER};
960
961#ifdef GLOG_NO_ABBREVIATED_SEVERITIES
962// wingdi.h defines ERROR to be 0. When we call LOG(ERROR), it gets
963// substituted with 0, and it expands to COMPACT_GOOGLE_LOG_0. To allow us
964// to keep using this syntax, we define this macro to do the same thing
965// as COMPACT_GOOGLE_LOG_ERROR.
966#define COMPACT_GOOGLE_LOG_0 COMPACT_GOOGLE_LOG_ERROR
967#define SYSLOG_0 SYSLOG_ERROR
968#define LOG_TO_STRING_0 LOG_TO_STRING_ERROR
969// Needed for LOG_IS_ON(ERROR).
970const LogSeverity GLOG_0 = GLOG_ERROR;
971#else
972// Users may include windows.h after logging.h without
973// GLOG_NO_ABBREVIATED_SEVERITIES nor WIN32_LEAN_AND_MEAN.
974// For this case, we cannot detect if ERROR is defined before users
975// actually use ERROR. Let's make an undefined symbol to warn users.
976# define GLOG_ERROR_MSG ERROR_macro_is_defined_Define_GLOG_NO_ABBREVIATED_SEVERITIES_before_including_logging_h_See_the_document_for_detail
977# define COMPACT_GOOGLE_LOG_0 GLOG_ERROR_MSG
978# define SYSLOG_0 GLOG_ERROR_MSG
979# define LOG_TO_STRING_0 GLOG_ERROR_MSG
980# define GLOG_0 GLOG_ERROR_MSG
981#endif
982
983// Plus some debug-logging macros that get compiled to nothing for production
984
985#if DCHECK_IS_ON()
986
987#define DLOG(severity) LOG(severity)
988#define DVLOG(verboselevel) VLOG(verboselevel)
989#define DLOG_IF(severity, condition) LOG_IF(severity, condition)
990#define DLOG_EVERY_N(severity, n) LOG_EVERY_N(severity, n)
991#define DLOG_IF_EVERY_N(severity, condition, n) \
992 LOG_IF_EVERY_N(severity, condition, n)
993#define DLOG_ASSERT(condition) LOG_ASSERT(condition)
994
995// debug-only checking. executed if DCHECK_IS_ON().
996#define DCHECK(condition) CHECK(condition)
997#define DCHECK_EQ(val1, val2) CHECK_EQ(val1, val2)
998#define DCHECK_NE(val1, val2) CHECK_NE(val1, val2)
999#define DCHECK_LE(val1, val2) CHECK_LE(val1, val2)
1000#define DCHECK_LT(val1, val2) CHECK_LT(val1, val2)
1001#define DCHECK_GE(val1, val2) CHECK_GE(val1, val2)
1002#define DCHECK_GT(val1, val2) CHECK_GT(val1, val2)
1003#define DCHECK_NOTNULL(val) CHECK_NOTNULL(val)
1004#define DCHECK_STREQ(str1, str2) CHECK_STREQ(str1, str2)
1005#define DCHECK_STRCASEEQ(str1, str2) CHECK_STRCASEEQ(str1, str2)
1006#define DCHECK_STRNE(str1, str2) CHECK_STRNE(str1, str2)
1007#define DCHECK_STRCASENE(str1, str2) CHECK_STRCASENE(str1, str2)
1008
1009#else // !DCHECK_IS_ON()
1010
1011#define DLOG(severity) \
1012 true ? (void) 0 : google::LogMessageVoidify() & LOG(severity)
1013
1014#define DVLOG(verboselevel) \
1015 (true || !VLOG_IS_ON(verboselevel)) ?\
1016 (void) 0 : google::LogMessageVoidify() & LOG(INFO)
1017
1018#define DLOG_IF(severity, condition) \
1019 (true || !(condition)) ? (void) 0 : google::LogMessageVoidify() & LOG(severity)
1020
1021#define DLOG_EVERY_N(severity, n) \
1022 true ? (void) 0 : google::LogMessageVoidify() & LOG(severity)
1023
1024#define DLOG_IF_EVERY_N(severity, condition, n) \
1025 (true || !(condition))? (void) 0 : google::LogMessageVoidify() & LOG(severity)
1026
1027#define DLOG_ASSERT(condition) \
1028 true ? (void) 0 : LOG_ASSERT(condition)
1029
1030// MSVC warning C4127: conditional expression is constant
1031#define DCHECK(condition) \
1032 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1033 while (false) \
1034 GLOG_MSVC_POP_WARNING() CHECK(condition)
1035
1036#define DCHECK_EQ(val1, val2) \
1037 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1038 while (false) \
1039 GLOG_MSVC_POP_WARNING() CHECK_EQ(val1, val2)
1040
1041#define DCHECK_NE(val1, val2) \
1042 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1043 while (false) \
1044 GLOG_MSVC_POP_WARNING() CHECK_NE(val1, val2)
1045
1046#define DCHECK_LE(val1, val2) \
1047 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1048 while (false) \
1049 GLOG_MSVC_POP_WARNING() CHECK_LE(val1, val2)
1050
1051#define DCHECK_LT(val1, val2) \
1052 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1053 while (false) \
1054 GLOG_MSVC_POP_WARNING() CHECK_LT(val1, val2)
1055
1056#define DCHECK_GE(val1, val2) \
1057 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1058 while (false) \
1059 GLOG_MSVC_POP_WARNING() CHECK_GE(val1, val2)
1060
1061#define DCHECK_GT(val1, val2) \
1062 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1063 while (false) \
1064 GLOG_MSVC_POP_WARNING() CHECK_GT(val1, val2)
1065
1066// You may see warnings in release mode if you don't use the return
1067// value of DCHECK_NOTNULL. Please just use DCHECK for such cases.
1068#define DCHECK_NOTNULL(val) (val)
1069
1070#define DCHECK_STREQ(str1, str2) \
1071 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1072 while (false) \
1073 GLOG_MSVC_POP_WARNING() CHECK_STREQ(str1, str2)
1074
1075#define DCHECK_STRCASEEQ(str1, str2) \
1076 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1077 while (false) \
1078 GLOG_MSVC_POP_WARNING() CHECK_STRCASEEQ(str1, str2)
1079
1080#define DCHECK_STRNE(str1, str2) \
1081 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1082 while (false) \
1083 GLOG_MSVC_POP_WARNING() CHECK_STRNE(str1, str2)
1084
1085#define DCHECK_STRCASENE(str1, str2) \
1086 GLOG_MSVC_PUSH_DISABLE_WARNING(4127) \
1087 while (false) \
1088 GLOG_MSVC_POP_WARNING() CHECK_STRCASENE(str1, str2)
1089
1090#endif // DCHECK_IS_ON()
1091
1092// Log only in verbose mode.
1093
1094#define VLOG(verboselevel) LOG_IF(INFO, VLOG_IS_ON(verboselevel))
1095
1096#define VLOG_IF(verboselevel, condition) \
1097 LOG_IF(INFO, (condition) && VLOG_IS_ON(verboselevel))
1098
1099#define VLOG_EVERY_N(verboselevel, n) \
1100 LOG_IF_EVERY_N(INFO, VLOG_IS_ON(verboselevel), n)
1101
1102#define VLOG_IF_EVERY_N(verboselevel, condition, n) \
1103 LOG_IF_EVERY_N(INFO, (condition) && VLOG_IS_ON(verboselevel), n)
1104
1105namespace base_logging {
1106
1107// LogMessage::LogStream is a std::ostream backed by this streambuf.
1108// This class ignores overflow and leaves two bytes at the end of the
1109// buffer to allow for a '\n' and '\0'.
1110class GOOGLE_GLOG_DLL_DECL LogStreamBuf : public std::streambuf {
1111 public:
1112 // REQUIREMENTS: "len" must be >= 2 to account for the '\n' and '\n'.
1113 LogStreamBuf(char *buf, int len) {
1114 setp(buf, buf + len - 2);
1115 }
1116 // This effectively ignores overflow.
1117 virtual int_type overflow(int_type ch) {
1118 return ch;
1119 }
1120
1121 // Legacy public ostrstream method.
1122 size_t pcount() const { return pptr() - pbase(); }
1123 char* pbase() const { return std::streambuf::pbase(); }
1124};
1125
1126} // namespace base_logging
1127
1128//
1129// This class more or less represents a particular log message. You
1130// create an instance of LogMessage and then stream stuff to it.
1131// When you finish streaming to it, ~LogMessage is called and the
1132// full message gets streamed to the appropriate destination.
1133//
1134// You shouldn't actually use LogMessage's constructor to log things,
1135// though. You should use the LOG() macro (and variants thereof)
1136// above.
1137class GOOGLE_GLOG_DLL_DECL LogMessage {
1138public:
1139 enum {
1140 // Passing kNoLogPrefix for the line number disables the
1141 // log-message prefix. Useful for using the LogMessage
1142 // infrastructure as a printing utility. See also the --log_prefix
1143 // flag for controlling the log-message prefix on an
1144 // application-wide basis.
1145 kNoLogPrefix = -1
1146 };
1147
1148 // LogStream inherit from non-DLL-exported class (std::ostrstream)
1149 // and VC++ produces a warning for this situation.
1150 // However, MSDN says "C4275 can be ignored in Microsoft Visual C++
1151 // 2005 if you are deriving from a type in the Standard C++ Library"
1152 // http://msdn.microsoft.com/en-us/library/3tdb471s(VS.80).aspx
1153 // Let's just ignore the warning.
1154#ifdef _MSC_VER
1155# pragma warning(disable: 4275)
1156#endif
1157 class GOOGLE_GLOG_DLL_DECL LogStream : public std::ostream {
1158#ifdef _MSC_VER
1159# pragma warning(default: 4275)
1160#endif
1161 public:
1162 LogStream(char *buf, int len, int ctr)
1163 : std::ostream(NULL),
1164 streambuf_(buf, len),
1165 ctr_(ctr),
1166 self_(this) {
1167 rdbuf(&streambuf_);
1168 }
1169
1170 int ctr() const { return ctr_; }
1171 void set_ctr(int ctr) { ctr_ = ctr; }
1172 LogStream* self() const { return self_; }
1173
1174 // Legacy std::streambuf methods.
1175 size_t pcount() const { return streambuf_.pcount(); }
1176 char* pbase() const { return streambuf_.pbase(); }
1177 char* str() const { return pbase(); }
1178
1179 private:
1180 LogStream(const LogStream&);
1181 LogStream& operator=(const LogStream&);
1182 base_logging::LogStreamBuf streambuf_;
1183 int ctr_; // Counter hack (for the LOG_EVERY_X() macro)
1184 LogStream *self_; // Consistency check hack
1185 };
1186
1187public:
1188 // icc 8 requires this typedef to avoid an internal compiler error.
1189 typedef void (LogMessage::*SendMethod)();
1190
1191 LogMessage(const char* file, int line, LogSeverity severity, int ctr,
1192 SendMethod send_method);
1193
1194 // Two special constructors that generate reduced amounts of code at
1195 // LOG call sites for common cases.
1196
1197 // Used for LOG(INFO): Implied are:
1198 // severity = INFO, ctr = 0, send_method = &LogMessage::SendToLog.
1199 //
1200 // Using this constructor instead of the more complex constructor above
1201 // saves 19 bytes per call site.
1202 LogMessage(const char* file, int line);
1203
1204 // Used for LOG(severity) where severity != INFO. Implied
1205 // are: ctr = 0, send_method = &LogMessage::SendToLog
1206 //
1207 // Using this constructor instead of the more complex constructor above
1208 // saves 17 bytes per call site.
1209 LogMessage(const char* file, int line, LogSeverity severity);
1210
1211 // Constructor to log this message to a specified sink (if not NULL).
1212 // Implied are: ctr = 0, send_method = &LogMessage::SendToSinkAndLog if
1213 // also_send_to_log is true, send_method = &LogMessage::SendToSink otherwise.
1214 LogMessage(const char* file, int line, LogSeverity severity, LogSink* sink,
1215 bool also_send_to_log);
1216
1217 // Constructor where we also give a vector<string> pointer
1218 // for storing the messages (if the pointer is not NULL).
1219 // Implied are: ctr = 0, send_method = &LogMessage::SaveOrSendToLog.
1220 LogMessage(const char* file, int line, LogSeverity severity,
1221 std::vector<std::string>* outvec);
1222
1223 // Constructor where we also give a string pointer for storing the
1224 // message (if the pointer is not NULL). Implied are: ctr = 0,
1225 // send_method = &LogMessage::WriteToStringAndLog.
1226 LogMessage(const char* file, int line, LogSeverity severity,
1227 std::string* message);
1228
1229 // A special constructor used for check failures
1230 LogMessage(const char* file, int line, const CheckOpString& result);
1231
1232 ~LogMessage();
1233
1234 // Flush a buffered message to the sink set in the constructor. Always
1235 // called by the destructor, it may also be called from elsewhere if
1236 // needed. Only the first call is actioned; any later ones are ignored.
1237 void Flush();
1238
1239 // An arbitrary limit on the length of a single log message. This
1240 // is so that streaming can be done more efficiently.
1241 static const size_t kMaxLogMessageLen;
1242
1243 // Theses should not be called directly outside of logging.*,
1244 // only passed as SendMethod arguments to other LogMessage methods:
1245 void SendToLog(); // Actually dispatch to the logs
1246 void SendToSyslogAndLog(); // Actually dispatch to syslog and the logs
1247
1248 // Call abort() or similar to perform LOG(FATAL) crash.
1249 static void __attribute__((noreturn)) Fail();
1250
1251 std::ostream& stream();
1252
1253 int preserved_errno() const;
1254
1255 // Must be called without the log_mutex held. (L < log_mutex)
1256 static int64 num_messages(int severity);
1257
1258 struct LogMessageData;
1259
1260private:
1261 // Fully internal SendMethod cases:
1262 void SendToSinkAndLog(); // Send to sink if provided and dispatch to the logs
1263 void SendToSink(); // Send to sink if provided, do nothing otherwise.
1264
1265 // Write to string if provided and dispatch to the logs.
1266 void WriteToStringAndLog();
1267
1268 void SaveOrSendToLog(); // Save to stringvec if provided, else to logs
1269
1270 void Init(const char* file, int line, LogSeverity severity,
1271 void (LogMessage::*send_method)());
1272
1273 // Used to fill in crash information during LOG(FATAL) failures.
1274 void RecordCrashReason(glog_internal_namespace_::CrashReason* reason);
1275
1276 // Counts of messages sent at each priority:
1277 static int64 num_messages_[NUM_SEVERITIES]; // under log_mutex
1278
1279 // We keep the data in a separate struct so that each instance of
1280 // LogMessage uses less stack space.
1281 LogMessageData* allocated_;
1282 LogMessageData* data_;
1283
1284 friend class LogDestination;
1285
1286 LogMessage(const LogMessage&);
1287 void operator=(const LogMessage&);
1288};
1289
1290// This class happens to be thread-hostile because all instances share
1291// a single data buffer, but since it can only be created just before
1292// the process dies, we don't worry so much.
1293class GOOGLE_GLOG_DLL_DECL LogMessageFatal : public LogMessage {
1294 public:
1295 LogMessageFatal(const char* file, int line);
1296 LogMessageFatal(const char* file, int line, const CheckOpString& result);
1297 __attribute__((noreturn)) ~LogMessageFatal();
1298};
1299
1300// A non-macro interface to the log facility; (useful
1301// when the logging level is not a compile-time constant).
1302inline void LogAtLevel(int const severity, std::string const &msg) {
1303 LogMessage(__FILE__, __LINE__, severity).stream() << msg;
1304}
1305
1306// A macro alternative of LogAtLevel. New code may want to use this
1307// version since there are two advantages: 1. this version outputs the
1308// file name and the line number where this macro is put like other
1309// LOG macros, 2. this macro can be used as C++ stream.
1310#define LOG_AT_LEVEL(severity) google::LogMessage(__FILE__, __LINE__, severity).stream()
1311
1312// Check if it's compiled in C++11 mode.
1313//
1314// GXX_EXPERIMENTAL_CXX0X is defined by gcc and clang up to at least
1315// gcc-4.7 and clang-3.1 (2011-12-13). __cplusplus was defined to 1
1316// in gcc before 4.7 (Crosstool 16) and clang before 3.1, but is
1317// defined according to the language version in effect thereafter.
1318// Microsoft Visual Studio 14 (2015) sets __cplusplus==199711 despite
1319// reasonably good C++11 support, so we set LANG_CXX for it and
1320// newer versions (_MSC_VER >= 1900).
1321#if (defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L || \
1322 (defined(_MSC_VER) && _MSC_VER >= 1900))
1323// Helper for CHECK_NOTNULL().
1324//
1325// In C++11, all cases can be handled by a single function. Since the value
1326// category of the argument is preserved (also for rvalue references),
1327// member initializer lists like the one below will compile correctly:
1328//
1329// Foo()
1330// : x_(CHECK_NOTNULL(MethodReturningUniquePtr())) {}
1331template <typename T>
1332T CheckNotNull(const char* file, int line, const char* names, T&& t) {
1333 if (t == nullptr) {
1334 LogMessageFatal(file, line, new std::string(names));
1335 }
1336 return std::forward<T>(t);
1337}
1338
1339#else
1340
1341// A small helper for CHECK_NOTNULL().
1342template <typename T>
1343T* CheckNotNull(const char *file, int line, const char *names, T* t) {
1344 if (t == NULL) {
1345 LogMessageFatal(file, line, new std::string(names));
1346 }
1347 return t;
1348}
1349#endif
1350
1351// Allow folks to put a counter in the LOG_EVERY_X()'ed messages. This
1352// only works if ostream is a LogStream. If the ostream is not a
1353// LogStream you'll get an assert saying as much at runtime.
1354GOOGLE_GLOG_DLL_DECL std::ostream& operator<<(std::ostream &os,
1355 const PRIVATE_Counter&);
1356
1357
1358// Derived class for PLOG*() above.
1359class GOOGLE_GLOG_DLL_DECL ErrnoLogMessage : public LogMessage {
1360 public:
1361
1362 ErrnoLogMessage(const char* file, int line, LogSeverity severity, int ctr,
1363 void (LogMessage::*send_method)());
1364
1365 // Postpends ": strerror(errno) [errno]".
1366 ~ErrnoLogMessage();
1367
1368 private:
1369 ErrnoLogMessage(const ErrnoLogMessage&);
1370 void operator=(const ErrnoLogMessage&);
1371};
1372
1373
1374// This class is used to explicitly ignore values in the conditional
1375// logging macros. This avoids compiler warnings like "value computed
1376// is not used" and "statement has no effect".
1377
1378class GOOGLE_GLOG_DLL_DECL LogMessageVoidify {
1379 public:
1380 LogMessageVoidify() { }
1381 // This has to be an operator with a precedence lower than << but
1382 // higher than ?:
1383 void operator&(std::ostream&) { }
1384};
1385
1386
1387// Flushes all log files that contains messages that are at least of
1388// the specified severity level. Thread-safe.
1389GOOGLE_GLOG_DLL_DECL void FlushLogFiles(LogSeverity min_severity);
1390
1391// Flushes all log files that contains messages that are at least of
1392// the specified severity level. Thread-hostile because it ignores
1393// locking -- used for catastrophic failures.
1394GOOGLE_GLOG_DLL_DECL void FlushLogFilesUnsafe(LogSeverity min_severity);
1395
1396//
1397// Set the destination to which a particular severity level of log
1398// messages is sent. If base_filename is "", it means "don't log this
1399// severity". Thread-safe.
1400//
1401GOOGLE_GLOG_DLL_DECL void SetLogDestination(LogSeverity severity,
1402 const char* base_filename);
1403
1404//
1405// Set the basename of the symlink to the latest log file at a given
1406// severity. If symlink_basename is empty, do not make a symlink. If
1407// you don't call this function, the symlink basename is the
1408// invocation name of the program. Thread-safe.
1409//
1410GOOGLE_GLOG_DLL_DECL void SetLogSymlink(LogSeverity severity,
1411 const char* symlink_basename);
1412
1413//
1414// Used to send logs to some other kind of destination
1415// Users should subclass LogSink and override send to do whatever they want.
1416// Implementations must be thread-safe because a shared instance will
1417// be called from whichever thread ran the LOG(XXX) line.
1418class GOOGLE_GLOG_DLL_DECL LogSink {
1419 public:
1420 virtual ~LogSink();
1421
1422 // Sink's logging logic (message_len is such as to exclude '\n' at the end).
1423 // This method can't use LOG() or CHECK() as logging system mutex(s) are held
1424 // during this call.
1425 virtual void send(LogSeverity severity, const char* full_filename,
1426 const char* base_filename, int line,
1427 const struct ::tm* tm_time,
1428 const char* message, size_t message_len) = 0;
1429
1430 // Redefine this to implement waiting for
1431 // the sink's logging logic to complete.
1432 // It will be called after each send() returns,
1433 // but before that LogMessage exits or crashes.
1434 // By default this function does nothing.
1435 // Using this function one can implement complex logic for send()
1436 // that itself involves logging; and do all this w/o causing deadlocks and
1437 // inconsistent rearrangement of log messages.
1438 // E.g. if a LogSink has thread-specific actions, the send() method
1439 // can simply add the message to a queue and wake up another thread that
1440 // handles real logging while itself making some LOG() calls;
1441 // WaitTillSent() can be implemented to wait for that logic to complete.
1442 // See our unittest for an example.
1443 virtual void WaitTillSent();
1444
1445 // Returns the normal text output of the log message.
1446 // Can be useful to implement send().
1447 static std::string ToString(LogSeverity severity, const char* file, int line,
1448 const struct ::tm* tm_time,
1449 const char* message, size_t message_len);
1450};
1451
1452// Add or remove a LogSink as a consumer of logging data. Thread-safe.
1453GOOGLE_GLOG_DLL_DECL void AddLogSink(LogSink *destination);
1454GOOGLE_GLOG_DLL_DECL void RemoveLogSink(LogSink *destination);
1455
1456//
1457// Specify an "extension" added to the filename specified via
1458// SetLogDestination. This applies to all severity levels. It's
1459// often used to append the port we're listening on to the logfile
1460// name. Thread-safe.
1461//
1462GOOGLE_GLOG_DLL_DECL void SetLogFilenameExtension(
1463 const char* filename_extension);
1464
1465//
1466// Make it so that all log messages of at least a particular severity
1467// are logged to stderr (in addition to logging to the usual log
1468// file(s)). Thread-safe.
1469//
1470GOOGLE_GLOG_DLL_DECL void SetStderrLogging(LogSeverity min_severity);
1471
1472//
1473// Make it so that all log messages go only to stderr. Thread-safe.
1474//
1475GOOGLE_GLOG_DLL_DECL void LogToStderr();
1476
1477//
1478// Make it so that all log messages of at least a particular severity are
1479// logged via email to a list of addresses (in addition to logging to the
1480// usual log file(s)). The list of addresses is just a string containing
1481// the email addresses to send to (separated by spaces, say). Thread-safe.
1482//
1483GOOGLE_GLOG_DLL_DECL void SetEmailLogging(LogSeverity min_severity,
1484 const char* addresses);
1485
1486// A simple function that sends email. dest is a commma-separated
1487// list of addressess. Thread-safe.
1488GOOGLE_GLOG_DLL_DECL bool SendEmail(const char *dest,
1489 const char *subject, const char *body);
1490
1491GOOGLE_GLOG_DLL_DECL const std::vector<std::string>& GetLoggingDirectories();
1492
1493// For tests only: Clear the internal [cached] list of logging directories to
1494// force a refresh the next time GetLoggingDirectories is called.
1495// Thread-hostile.
1496void TestOnly_ClearLoggingDirectoriesList();
1497
1498// Returns a set of existing temporary directories, which will be a
1499// subset of the directories returned by GetLogginDirectories().
1500// Thread-safe.
1501GOOGLE_GLOG_DLL_DECL void GetExistingTempDirectories(
1502 std::vector<std::string>* list);
1503
1504// Print any fatal message again -- useful to call from signal handler
1505// so that the last thing in the output is the fatal message.
1506// Thread-hostile, but a race is unlikely.
1507GOOGLE_GLOG_DLL_DECL void ReprintFatalMessage();
1508
1509// Truncate a log file that may be the append-only output of multiple
1510// processes and hence can't simply be renamed/reopened (typically a
1511// stdout/stderr). If the file "path" is > "limit" bytes, copy the
1512// last "keep" bytes to offset 0 and truncate the rest. Since we could
1513// be racing with other writers, this approach has the potential to
1514// lose very small amounts of data. For security, only follow symlinks
1515// if the path is /proc/self/fd/*
1516GOOGLE_GLOG_DLL_DECL void TruncateLogFile(const char *path,
1517 int64 limit, int64 keep);
1518
1519// Truncate stdout and stderr if they are over the value specified by
1520// --max_log_size; keep the final 1MB. This function has the same
1521// race condition as TruncateLogFile.
1522GOOGLE_GLOG_DLL_DECL void TruncateStdoutStderr();
1523
1524// Return the string representation of the provided LogSeverity level.
1525// Thread-safe.
1526GOOGLE_GLOG_DLL_DECL const char* GetLogSeverityName(LogSeverity severity);
1527
1528// ---------------------------------------------------------------------
1529// Implementation details that are not useful to most clients
1530// ---------------------------------------------------------------------
1531
1532// A Logger is the interface used by logging modules to emit entries
1533// to a log. A typical implementation will dump formatted data to a
1534// sequence of files. We also provide interfaces that will forward
1535// the data to another thread so that the invoker never blocks.
1536// Implementations should be thread-safe since the logging system
1537// will write to them from multiple threads.
1538
1539namespace base {
1540
1541class GOOGLE_GLOG_DLL_DECL Logger {
1542 public:
1543 virtual ~Logger();
1544
1545 // Writes "message[0,message_len-1]" corresponding to an event that
1546 // occurred at "timestamp". If "force_flush" is true, the log file
1547 // is flushed immediately.
1548 //
1549 // The input message has already been formatted as deemed
1550 // appropriate by the higher level logging facility. For example,
1551 // textual log messages already contain timestamps, and the
1552 // file:linenumber header.
1553 virtual void Write(bool force_flush,
1554 time_t timestamp,
1555 const char* message,
1556 int message_len) = 0;
1557
1558 // Flush any buffered messages
1559 virtual void Flush() = 0;
1560
1561 // Get the current LOG file size.
1562 // The returned value is approximate since some
1563 // logged data may not have been flushed to disk yet.
1564 virtual uint32 LogSize() = 0;
1565};
1566
1567// Get the logger for the specified severity level. The logger
1568// remains the property of the logging module and should not be
1569// deleted by the caller. Thread-safe.
1570extern GOOGLE_GLOG_DLL_DECL Logger* GetLogger(LogSeverity level);
1571
1572// Set the logger for the specified severity level. The logger
1573// becomes the property of the logging module and should not
1574// be deleted by the caller. Thread-safe.
1575extern GOOGLE_GLOG_DLL_DECL void SetLogger(LogSeverity level, Logger* logger);
1576
1577}
1578
1579// glibc has traditionally implemented two incompatible versions of
1580// strerror_r(). There is a poorly defined convention for picking the
1581// version that we want, but it is not clear whether it even works with
1582// all versions of glibc.
1583// So, instead, we provide this wrapper that automatically detects the
1584// version that is in use, and then implements POSIX semantics.
1585// N.B. In addition to what POSIX says, we also guarantee that "buf" will
1586// be set to an empty string, if this function failed. This means, in most
1587// cases, you do not need to check the error code and you can directly
1588// use the value of "buf". It will never have an undefined value.
1589// DEPRECATED: Use StrError(int) instead.
1590GOOGLE_GLOG_DLL_DECL int posix_strerror_r(int err, char *buf, size_t len);
1591
1592// A thread-safe replacement for strerror(). Returns a string describing the
1593// given POSIX error code.
1594GOOGLE_GLOG_DLL_DECL std::string StrError(int err);
1595
1596// A class for which we define operator<<, which does nothing.
1597class GOOGLE_GLOG_DLL_DECL NullStream : public LogMessage::LogStream {
1598 public:
1599 // Initialize the LogStream so the messages can be written somewhere
1600 // (they'll never be actually displayed). This will be needed if a
1601 // NullStream& is implicitly converted to LogStream&, in which case
1602 // the overloaded NullStream::operator<< will not be invoked.
1603 NullStream() : LogMessage::LogStream(message_buffer_, 1, 0) { }
1604 NullStream(const char* /*file*/, int /*line*/,
1605 const CheckOpString& /*result*/) :
1606 LogMessage::LogStream(message_buffer_, 1, 0) { }
1607 NullStream &stream() { return *this; }
1608 private:
1609 // A very short buffer for messages (which we discard anyway). This
1610 // will be needed if NullStream& converted to LogStream& (e.g. as a
1611 // result of a conditional expression).
1612 char message_buffer_[2];
1613};
1614
1615// Do nothing. This operator is inline, allowing the message to be
1616// compiled away. The message will not be compiled away if we do
1617// something like (flag ? LOG(INFO) : LOG(ERROR)) << message; when
1618// SKIP_LOG=WARNING. In those cases, NullStream will be implicitly
1619// converted to LogStream and the message will be computed and then
1620// quietly discarded.
1621template<class T>
1622inline NullStream& operator<<(NullStream &str, const T &) { return str; }
1623
1624// Similar to NullStream, but aborts the program (without stack
1625// trace), like LogMessageFatal.
1626class GOOGLE_GLOG_DLL_DECL NullStreamFatal : public NullStream {
1627 public:
1628 NullStreamFatal() { }
1629 NullStreamFatal(const char* file, int line, const CheckOpString& result) :
1630 NullStream(file, line, result) { }
1631 __attribute__((noreturn)) ~NullStreamFatal() throw () { _exit(1); }
1632};
1633
1634// Install a signal handler that will dump signal information and a stack
1635// trace when the program crashes on certain signals. We'll install the
1636// signal handler for the following signals.
1637//
1638// SIGSEGV, SIGILL, SIGFPE, SIGABRT, SIGBUS, and SIGTERM.
1639//
1640// By default, the signal handler will write the failure dump to the
1641// standard error. You can customize the destination by installing your
1642// own writer function by InstallFailureWriter() below.
1643//
1644// Note on threading:
1645//
1646// The function should be called before threads are created, if you want
1647// to use the failure signal handler for all threads. The stack trace
1648// will be shown only for the thread that receives the signal. In other
1649// words, stack traces of other threads won't be shown.
1650GOOGLE_GLOG_DLL_DECL void InstallFailureSignalHandler();
1651
1652// Installs a function that is used for writing the failure dump. "data"
1653// is the pointer to the beginning of a message to be written, and "size"
1654// is the size of the message. You should not expect the data is
1655// terminated with '\0'.
1656GOOGLE_GLOG_DLL_DECL void InstallFailureWriter(
1657 void (*writer)(const char* data, int size));
1658
1659}
1660
1661#endif // _LOGGING_H_
1662