1 // Copyright (c) 1999, Google Inc.
2 // All rights reserved.
4 // Redistribution and use in source and binary forms, with or without
5 // modification, are permitted provided that the following conditions are
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
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.
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.
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.
43 #if @ac_cv_have_unistd_h@
56 // Annoying stuff for windows -- makes sure clients can import these functions
57 #ifndef GOOGLE_GLOG_DLL_DECL
58 # if defined(_WIN32) && !defined(__CYGWIN__)
59 # define GOOGLE_GLOG_DLL_DECL __declspec(dllimport)
61 # define GOOGLE_GLOG_DLL_DECL
65 // We care a lot about number of bits things take up. Unfortunately,
66 // systems define their bit-specific ints in a lot of different ways.
67 // We use our own way, and have a typedef to get there.
68 // Note: these commands below may look like "#if 1" or "#if 0", but
69 // that's because they were constructed that way at ./configure time.
70 // Look at logging.h.in to see how they're calculated (based on your config).
71 #if @ac_cv_have_stdint_h@
72 #include <stdint.h> // the normal place uint16_t is defined
74 #if @ac_cv_have_systypes_h@
75 #include <sys/types.h> // the normal place u_int16_t is defined
77 #if @ac_cv_have_inttypes_h@
78 #include <inttypes.h> // a third place for uint16_t or u_int16_t
81 #if @ac_cv_have_libgflags@
82 #include <gflags/gflags.h>
85 @ac_google_start_namespace@
87 #if @ac_cv_have_uint16_t@ // the C99 format
88 typedef int32_t int32;
89 typedef uint32_t uint32;
90 typedef int64_t int64;
91 typedef uint64_t uint64;
92 #elif @ac_cv_have_u_int16_t@ // the BSD format
93 typedef int32_t int32;
94 typedef u_int32_t uint32;
95 typedef int64_t int64;
96 typedef u_int64_t uint64;
97 #elif @ac_cv_have___uint16@ // the windows (vc7) format
98 typedef __int32 int32;
99 typedef unsigned __int32 uint32;
100 typedef __int64 int64;
101 typedef unsigned __int64 uint64;
103 #error Do not know how to define a 32-bit integer quantity on your system
106 @ac_google_end_namespace@
108 // The global value of GOOGLE_STRIP_LOG. All the messages logged to
109 // LOG(XXX) with severity less than GOOGLE_STRIP_LOG will not be displayed.
110 // If it can be determined at compile time that the message will not be
111 // printed, the statement will be compiled out.
113 // Example: to strip out all INFO and WARNING messages, use the value
114 // of 2 below. To make an exception for WARNING messages from a single
115 // file, add "#define GOOGLE_STRIP_LOG 1" to that file _before_ including
117 #ifndef GOOGLE_STRIP_LOG
118 #define GOOGLE_STRIP_LOG 0
121 // GCC can be told that a certain branch is not likely to be taken (for
122 // instance, a CHECK failure), and use that information in static analysis.
123 // Giving it this information can help it optimize for the common case in
124 // the absence of better information (ie. -fprofile-arcs).
126 #ifndef GOOGLE_PREDICT_BRANCH_NOT_TAKEN
127 #if @ac_cv_have___builtin_expect@
128 #define GOOGLE_PREDICT_BRANCH_NOT_TAKEN(x) (__builtin_expect(x, 0))
130 #define GOOGLE_PREDICT_BRANCH_NOT_TAKEN(x) x
134 // Make a bunch of macros for logging. The way to log things is to stream
135 // things to LOG(<a particular severity level>). E.g.,
137 // LOG(INFO) << "Found " << num_cookies << " cookies";
139 // You can capture log messages in a string, rather than reporting them
142 // vector<string> errors;
143 // LOG_STRING(ERROR, &errors) << "Couldn't parse cookie #" << cookie_num;
145 // This pushes back the new error onto 'errors'; if given a NULL pointer,
146 // it reports the error via LOG(ERROR).
148 // You can also do conditional logging:
150 // LOG_IF(INFO, num_cookies > 10) << "Got lots of cookies";
152 // You can also do occasional logging (log every n'th occurrence of an
155 // LOG_EVERY_N(INFO, 10) << "Got the " << COUNTER << "th cookie";
157 // The above will cause log messages to be output on the 1st, 11th, 21st, ...
158 // times it is executed. Note that the special COUNTER value is used to
159 // identify which repetition is happening.
161 // You can also do occasional conditional logging (log every n'th
162 // occurrence of an event, when condition is satisfied):
164 // LOG_IF_EVERY_N(INFO, (size > 1024), 10) << "Got the " << COUNTER
165 // << "th big cookie";
167 // You can log messages the first N times your code executes a line. E.g.
169 // LOG_FIRST_N(INFO, 20) << "Got the " << COUNTER << "th cookie";
171 // Outputs log messages for the first 20 times it is executed.
173 // Analogous SYSLOG, SYSLOG_IF, and SYSLOG_EVERY_N macros are available.
174 // These log to syslog as well as to the normal logs. If you use these at
175 // all, you need to be aware that syslog can drastically reduce performance,
176 // especially if it is configured for remote logging! Don't use these
177 // unless you fully understand this and have a concrete need to use them.
178 // Even then, try to minimize your use of them.
180 // There are also "debug mode" logging macros like the ones above:
182 // DLOG(INFO) << "Found cookies";
184 // DLOG_IF(INFO, num_cookies > 10) << "Got lots of cookies";
186 // DLOG_EVERY_N(INFO, 10) << "Got the " << COUNTER << "th cookie";
188 // All "debug mode" logging is compiled away to nothing for non-debug mode
193 // LOG_ASSERT(assertion);
194 // DLOG_ASSERT(assertion);
196 // which is syntactic sugar for {,D}LOG_IF(FATAL, assert fails) << assertion;
198 // There are "verbose level" logging macros. They look like
200 // VLOG(1) << "I'm printed when you run the program with --v=1 or more";
201 // VLOG(2) << "I'm printed when you run the program with --v=2 or more";
203 // These always log at the INFO log level (when they log at all).
204 // The verbose logging can also be turned on module-by-module. For instance,
205 // --vmodule=mapreduce=2,file=1,gfs*=3 --v=0
207 // a. VLOG(2) and lower messages to be printed from mapreduce.{h,cc}
208 // b. VLOG(1) and lower messages to be printed from file.{h,cc}
209 // c. VLOG(3) and lower messages to be printed from files prefixed with "gfs"
210 // d. VLOG(0) and lower messages to be printed from elsewhere
212 // The wildcarding functionality shown by (c) supports both '*' (match
213 // 0 or more characters) and '?' (match any single character) wildcards.
215 // There's also VLOG_IS_ON(n) "verbose level" condition macro. To be used as
217 // if (VLOG_IS_ON(2)) {
218 // // do some logging preparation and logging
219 // // that can't be accomplished with just VLOG(2) << ...;
222 // There are also VLOG_IF, VLOG_EVERY_N and VLOG_IF_EVERY_N "verbose level"
223 // condition macros for sample cases, when some extra computation and
224 // preparation for logs is not needed.
225 // VLOG_IF(1, (size > 1024))
226 // << "I'm printed when size is more than 1024 and when you run the "
227 // "program with --v=1 or more";
228 // VLOG_EVERY_N(1, 10)
229 // << "I'm printed every 10th occurrence, and when you run the program "
230 // "with --v=1 or more. Present occurence is " << COUNTER;
231 // VLOG_IF_EVERY_N(1, (size > 1024), 10)
232 // << "I'm printed on every 10th occurence of case when size is more "
233 // " than 1024, when you run the program with --v=1 or more. ";
234 // "Present occurence is " << COUNTER;
236 // The supported severity levels for macros that allow you to specify one
237 // are (in increasing order of severity) INFO, WARNING, ERROR, and FATAL.
238 // Note that messages of a given severity are logged not only in the
239 // logfile for that severity, but also in all logfiles of lower severity.
240 // E.g., a message of severity FATAL will be logged to the logfiles of
241 // severity FATAL, ERROR, WARNING, and INFO.
243 // There is also the special severity of DFATAL, which logs FATAL in
244 // debug mode, ERROR in normal mode.
246 // Very important: logging a message at the FATAL severity level causes
247 // the program to terminate (after the message is logged).
249 // Unless otherwise specified, logs will be written to the filename
250 // "<program name>.<hostname>.<user name>.log.<severity level>.", followed
251 // by the date, time, and pid (you can't prevent the date, time, and pid
252 // from being in the filename).
254 // The logging code takes two flags:
255 // --v=# set the verbose level
256 // --logtostderr log all the messages to stderr instead of to logfiles
258 // LOG LINE PREFIX FORMAT
260 // Log lines have this form:
262 // Lmmdd hh:mm:ss.uuuuuu threadid file:line] msg...
264 // where the fields are defined as follows:
266 // L A single character, representing the log level
268 // mm The month (zero padded; ie May is '05')
269 // dd The day (zero padded)
270 // hh:mm:ss.uuuuuu Time in hours, minutes and fractional seconds
271 // threadid The space-padded thread ID as returned by GetTID()
272 // (this matches the PID on Linux)
273 // file The file name
274 // line The line number
275 // msg The user-supplied message
279 // I1103 11:57:31.739339 24395 google.cc:2341] Command line: ./some_prog
280 // I1103 11:57:31.739403 24395 google.cc:2342] Process id 24395
282 // NOTE: although the microseconds are useful for comparing events on
283 // a single machine, clocks on different machines may not be well
284 // synchronized. Hence, use caution when comparing the low bits of
285 // timestamps from different machines.
287 #ifndef DECLARE_VARIABLE
288 #define MUST_UNDEF_GFLAGS_DECLARE_MACROS
289 #define DECLARE_VARIABLE(type, name, tn) \
290 namespace FLAG__namespace_do_not_use_directly_use_DECLARE_##tn##_instead { \
291 extern GOOGLE_GLOG_DLL_DECL type FLAGS_##name; \
293 using FLAG__namespace_do_not_use_directly_use_DECLARE_##tn##_instead::FLAGS_##name
295 // bool specialization
296 #define DECLARE_bool(name) \
297 DECLARE_VARIABLE(bool, name, bool)
299 // int32 specialization
300 #define DECLARE_int32(name) \
301 DECLARE_VARIABLE(@ac_google_namespace@::int32, name, int32)
303 // Special case for string, because we have to specify the namespace
304 // std::string, which doesn't play nicely with our FLAG__namespace hackery.
305 #define DECLARE_string(name) \
306 namespace FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead { \
307 extern GOOGLE_GLOG_DLL_DECL std::string FLAGS_##name; \
309 using FLAG__namespace_do_not_use_directly_use_DECLARE_string_instead::FLAGS_##name
312 // Set whether log messages go to stderr instead of logfiles
313 DECLARE_bool(logtostderr);
315 // Set whether log messages go to stderr in addition to logfiles.
316 DECLARE_bool(alsologtostderr);
318 // Log messages at a level >= this flag are automatically sent to
319 // stderr in addition to log files.
320 DECLARE_int32(stderrthreshold);
322 // Set whether the log prefix should be prepended to each line of output.
323 DECLARE_bool(log_prefix);
325 // Log messages at a level <= this flag are buffered.
326 // Log messages at a higher level are flushed immediately.
327 DECLARE_int32(logbuflevel);
329 // Sets the maximum number of seconds which logs may be buffered for.
330 DECLARE_int32(logbufsecs);
332 // Log suppression level: messages logged at a lower level than this
334 DECLARE_int32(minloglevel);
336 // If specified, logfiles are written into this directory instead of the
337 // default logging directory.
338 DECLARE_string(log_dir);
340 // Sets the path of the directory into which to put additional links
342 DECLARE_string(log_link);
344 DECLARE_int32(v); // in vlog_is_on.cc
346 // Sets the maximum log file size (in MB).
347 DECLARE_int32(max_log_size);
349 // Sets whether to avoid logging to the disk if the disk is full.
350 DECLARE_bool(stop_logging_if_full_disk);
352 #ifdef MUST_UNDEF_GFLAGS_DECLARE_MACROS
353 #undef MUST_UNDEF_GFLAGS_DECLARE_MACROS
354 #undef DECLARE_VARIABLE
357 #undef DECLARE_string
360 // Log messages below the GOOGLE_STRIP_LOG level will be compiled away for
361 // security reasons. See LOG(severtiy) below.
363 // A few definitions of macros that don't generate much code. Since
364 // LOG(INFO) and its ilk are used all over our code, it's
365 // better to have compact code for these operations.
367 #if GOOGLE_STRIP_LOG == 0
368 #define COMPACT_GOOGLE_LOG_INFO @ac_google_namespace@::LogMessage( \
370 #define LOG_TO_STRING_INFO(message) @ac_google_namespace@::LogMessage( \
371 __FILE__, __LINE__, @ac_google_namespace@::INFO, message)
373 #define COMPACT_GOOGLE_LOG_INFO @ac_google_namespace@::NullStream()
374 #define LOG_TO_STRING_INFO(message) @ac_google_namespace@::NullStream()
377 #if GOOGLE_STRIP_LOG <= 1
378 #define COMPACT_GOOGLE_LOG_WARNING @ac_google_namespace@::LogMessage( \
379 __FILE__, __LINE__, @ac_google_namespace@::WARNING)
380 #define LOG_TO_STRING_WARNING(message) @ac_google_namespace@::LogMessage( \
381 __FILE__, __LINE__, @ac_google_namespace@::WARNING, message)
383 #define COMPACT_GOOGLE_LOG_WARNING @ac_google_namespace@::NullStream()
384 #define LOG_TO_STRING_WARNING(message) @ac_google_namespace@::NullStream()
387 #if GOOGLE_STRIP_LOG <= 2
388 #define COMPACT_GOOGLE_LOG_ERROR @ac_google_namespace@::LogMessage( \
389 __FILE__, __LINE__, @ac_google_namespace@::ERROR)
390 #define LOG_TO_STRING_ERROR(message) @ac_google_namespace@::LogMessage( \
391 __FILE__, __LINE__, @ac_google_namespace@::ERROR, message)
393 #define COMPACT_GOOGLE_LOG_ERROR @ac_google_namespace@::NullStream()
394 #define LOG_TO_STRING_ERROR(message) @ac_google_namespace@::NullStream()
397 #if GOOGLE_STRIP_LOG <= 3
398 #define COMPACT_GOOGLE_LOG_FATAL @ac_google_namespace@::LogMessageFatal( \
400 #define LOG_TO_STRING_FATAL(message) @ac_google_namespace@::LogMessage( \
401 __FILE__, __LINE__, @ac_google_namespace@::FATAL, message)
403 #define COMPACT_GOOGLE_LOG_FATAL @ac_google_namespace@::NullStreamFatal()
404 #define LOG_TO_STRING_FATAL(message) @ac_google_namespace@::NullStreamFatal()
407 // For DFATAL, we want to use LogMessage (as opposed to
408 // LogMessageFatal), to be consistent with the original behavior.
410 #define COMPACT_GOOGLE_LOG_DFATAL COMPACT_GOOGLE_LOG_ERROR
411 #elif GOOGLE_STRIP_LOG <= 3
412 #define COMPACT_GOOGLE_LOG_DFATAL @ac_google_namespace@::LogMessage( \
413 __FILE__, __LINE__, @ac_google_namespace@::FATAL)
415 #define COMPACT_GOOGLE_LOG_DFATAL @ac_google_namespace@::NullStreamFatal()
418 #define GOOGLE_LOG_INFO(counter) @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::INFO, counter, &@ac_google_namespace@::LogMessage::SendToLog)
419 #define SYSLOG_INFO(counter) \
420 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::INFO, counter, \
421 &@ac_google_namespace@::LogMessage::SendToSyslogAndLog)
422 #define GOOGLE_LOG_WARNING(counter) \
423 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::WARNING, counter, \
424 &@ac_google_namespace@::LogMessage::SendToLog)
425 #define SYSLOG_WARNING(counter) \
426 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::WARNING, counter, \
427 &@ac_google_namespace@::LogMessage::SendToSyslogAndLog)
428 #define GOOGLE_LOG_ERROR(counter) \
429 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::ERROR, counter, \
430 &@ac_google_namespace@::LogMessage::SendToLog)
431 #define SYSLOG_ERROR(counter) \
432 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::ERROR, counter, \
433 &@ac_google_namespace@::LogMessage::SendToSyslogAndLog)
434 #define GOOGLE_LOG_FATAL(counter) \
435 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::FATAL, counter, \
436 &@ac_google_namespace@::LogMessage::SendToLog)
437 #define SYSLOG_FATAL(counter) \
438 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::FATAL, counter, \
439 &@ac_google_namespace@::LogMessage::SendToSyslogAndLog)
440 #define GOOGLE_LOG_DFATAL(counter) \
441 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::DFATAL_LEVEL, counter, \
442 &@ac_google_namespace@::LogMessage::SendToLog)
443 #define SYSLOG_DFATAL(counter) \
444 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, @ac_google_namespace@::DFATAL_LEVEL, counter, \
445 &@ac_google_namespace@::LogMessage::SendToSyslogAndLog)
447 #if defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__) || defined(__CYGWIN32__)
448 // A very useful logging macro to log windows errors:
449 #define LOG_SYSRESULT(result) \
450 if (FAILED(result)) { \
451 LPTSTR message = NULL; \
452 LPTSTR msg = reinterpret_cast<LPTSTR>(&message); \
453 DWORD message_length = FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | \
454 FORMAT_MESSAGE_FROM_SYSTEM, \
455 0, result, 0, msg, 100, NULL); \
456 if (message_length > 0) { \
457 @ac_google_namespace@::LogMessage(__FILE__, __LINE__, ERROR, 0, \
458 &@ac_google_namespace@::LogMessage::SendToLog).stream() << message; \
459 LocalFree(message); \
464 // We use the preprocessor's merging operator, "##", so that, e.g.,
465 // LOG(INFO) becomes the token GOOGLE_LOG_INFO. There's some funny
466 // subtle difference between ostream member streaming functions (e.g.,
467 // ostream::operator<<(int) and ostream non-member streaming functions
468 // (e.g., ::operator<<(ostream&, string&): it turns out that it's
469 // impossible to stream something like a string directly to an unnamed
470 // ostream. We employ a neat hack by calling the stream() member
471 // function of LogMessage which seems to avoid the problem.
472 #define LOG(severity) COMPACT_GOOGLE_LOG_ ## severity.stream()
473 #define SYSLOG(severity) SYSLOG_ ## severity(0).stream()
475 @ac_google_start_namespace@
477 // They need the definitions of integer types.
478 #include "glog/log_severity.h"
479 #include "glog/vlog_is_on.h"
481 // Initialize google's logging library. You will see the program name
482 // specified by argv0 in log outputs.
483 GOOGLE_GLOG_DLL_DECL void InitGoogleLogging(const char* argv0);
485 // Install a function which will be called after LOG(FATAL).
486 GOOGLE_GLOG_DLL_DECL void InstallFailureFunction(void (*fail_func)());
488 class LogSink; // defined below
490 // If a non-NULL sink pointer is given, we push this message to that sink.
491 // For LOG_TO_SINK we then do normal LOG(severity) logging as well.
492 // This is useful for capturing messages and passing/storing them
493 // somewhere more specific than the global log of the process.
496 // LogSeverity severity;
497 // The cast is to disambiguate NULL arguments.
498 #define LOG_TO_SINK(sink, severity) \
499 @ac_google_namespace@::LogMessage( \
500 __FILE__, __LINE__, \
501 @ac_google_namespace@::severity, \
502 static_cast<@ac_google_namespace@::LogSink*>(sink), true).stream()
503 #define LOG_TO_SINK_BUT_NOT_TO_LOGFILE(sink, severity) \
504 @ac_google_namespace@::LogMessage( \
505 __FILE__, __LINE__, \
506 @ac_google_namespace@::severity, \
507 static_cast<@ac_google_namespace@::LogSink*>(sink), false).stream()
509 // If a non-NULL string pointer is given, we write this message to that string.
510 // We then do normal LOG(severity) logging as well.
511 // This is useful for capturing messages and storing them somewhere more
512 // specific than the global log of the process.
515 // LogSeverity severity;
516 // The cast is to disambiguate NULL arguments.
517 // NOTE: LOG(severity) expands to LogMessage().stream() for the specified
519 #define LOG_TO_STRING(severity, message) \
520 LOG_TO_STRING_##severity(static_cast<string*>(message)).stream()
522 // If a non-NULL pointer is given, we push the message onto the end
523 // of a vector of strings; otherwise, we report it with LOG(severity).
524 // This is handy for capturing messages and perhaps passing them back
525 // to the caller, rather than reporting them immediately.
527 // LogSeverity severity;
528 // vector<string> *outvec;
529 // The cast is to disambiguate NULL arguments.
530 #define LOG_STRING(severity, outvec) \
531 LOG_TO_STRING_##severity(static_cast<vector<string>*>(outvec)).stream()
533 #define LOG_IF(severity, condition) \
534 !(condition) ? (void) 0 : @ac_google_namespace@::LogMessageVoidify() & LOG(severity)
535 #define SYSLOG_IF(severity, condition) \
536 !(condition) ? (void) 0 : @ac_google_namespace@::LogMessageVoidify() & SYSLOG(severity)
538 #define LOG_ASSERT(condition) \
539 LOG_IF(FATAL, !(condition)) << "Assert failed: " #condition
540 #define SYSLOG_ASSERT(condition) \
541 SYSLOG_IF(FATAL, !(condition)) << "Assert failed: " #condition
543 // CHECK dies with a fatal error if condition is not true. It is *not*
544 // controlled by NDEBUG, so the check will be executed regardless of
545 // compilation mode. Therefore, it is safe to do things like:
546 // CHECK(fp->Write(x) == 4)
547 #define CHECK(condition) \
548 LOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN(!(condition))) \
549 << "Check failed: " #condition " "
551 // A container for a string pointer which can be evaluated to a bool -
552 // true iff the pointer is NULL.
553 struct CheckOpString {
554 CheckOpString(std::string* str) : str_(str) { }
555 // No destructor: if str_ is non-NULL, we're about to LOG(FATAL),
556 // so there's no point in cleaning up str_.
557 operator bool() const {
558 return GOOGLE_PREDICT_BRANCH_NOT_TAKEN(str_ != NULL);
563 // Function is overloaded for integral types to allow static const
564 // integrals declared in classes and not defined to be used as arguments to
565 // CHECK* macros. It's not encouraged though.
567 inline const T& GetReferenceableValue(const T& t) { return t; }
568 inline char GetReferenceableValue(char t) { return t; }
569 inline unsigned char GetReferenceableValue(unsigned char t) { return t; }
570 inline signed char GetReferenceableValue(signed char t) { return t; }
571 inline short GetReferenceableValue(short t) { return t; }
572 inline unsigned short GetReferenceableValue(unsigned short t) { return t; }
573 inline int GetReferenceableValue(int t) { return t; }
574 inline unsigned int GetReferenceableValue(unsigned int t) { return t; }
575 inline long GetReferenceableValue(long t) { return t; }
576 inline unsigned long GetReferenceableValue(unsigned long t) { return t; }
577 inline long long GetReferenceableValue(long long t) { return t; }
578 inline unsigned long long GetReferenceableValue(unsigned long long t) {
582 // This is a dummy class to define the following operator.
583 struct DummyClassToDefineOperator {};
585 @ac_google_end_namespace@
587 // Define global operator<< to declare using ::operator<<.
588 // This declaration will allow use to use CHECK macros for user
589 // defined classes which have operator<< (e.g., stl_logging.h).
590 inline std::ostream& operator<<(
591 std::ostream& out, const google::DummyClassToDefineOperator&) {
595 @ac_google_start_namespace@
597 // Build the error message string.
598 template<class t1, class t2>
599 std::string* MakeCheckOpString(const t1& v1, const t2& v2, const char* names) {
600 // It means that we cannot use stl_logging if compiler doesn't
601 // support using expression for operator.
602 // TODO(hamaji): Figure out a way to fix.
603 #if @ac_cv_cxx_using_operator@
607 ss << names << " (" << v1 << " vs. " << v2 << ")";
608 return new std::string(ss.str(), ss.pcount());
611 // Helper functions for CHECK_OP macro.
612 // The (int, int) specialization works around the issue that the compiler
613 // will not instantiate the template version of the function on values of
614 // unnamed enum type - see comment below.
615 #define DEFINE_CHECK_OP_IMPL(name, op) \
616 template <class t1, class t2> \
617 inline std::string* Check##name##Impl(const t1& v1, const t2& v2, \
618 const char* names) { \
619 if (v1 op v2) return NULL; \
620 else return MakeCheckOpString(v1, v2, names); \
622 inline std::string* Check##name##Impl(int v1, int v2, const char* names) { \
623 return Check##name##Impl<int, int>(v1, v2, names); \
626 // Use _EQ, _NE, _LE, etc. in case the file including base/logging.h
627 // provides its own #defines for the simpler names EQ, NE, LE, etc.
628 // This happens if, for example, those are used as token names in a
630 DEFINE_CHECK_OP_IMPL(_EQ, ==)
631 DEFINE_CHECK_OP_IMPL(_NE, !=)
632 DEFINE_CHECK_OP_IMPL(_LE, <=)
633 DEFINE_CHECK_OP_IMPL(_LT, < )
634 DEFINE_CHECK_OP_IMPL(_GE, >=)
635 DEFINE_CHECK_OP_IMPL(_GT, > )
636 #undef DEFINE_CHECK_OP_IMPL
638 // Helper macro for binary operators.
639 // Don't use this macro directly in your code, use CHECK_EQ et al below.
641 #if defined(STATIC_ANALYSIS)
642 // Only for static analysis tool to know that it is equivalent to assert
643 #define CHECK_OP_LOG(name, op, val1, val2, log) CHECK((val1) op (val2))
644 #elif !defined(NDEBUG)
645 // In debug mode, avoid constructing CheckOpStrings if possible,
646 // to reduce the overhead of CHECK statments by 2x.
647 // Real DCHECK-heavy tests have seen 1.5x speedups.
649 // The meaning of "string" might be different between now and
650 // when this macro gets invoked (e.g., if someone is experimenting
651 // with other string implementations that get defined after this
652 // file is included). Save the current meaning now and use it
654 typedef std::string _Check_string;
655 #define CHECK_OP_LOG(name, op, val1, val2, log) \
656 while (@ac_google_namespace@::_Check_string* _result = \
657 @ac_google_namespace@::Check##name##Impl( \
658 @ac_google_namespace@::GetReferenceableValue(val1), \
659 @ac_google_namespace@::GetReferenceableValue(val2), \
660 #val1 " " #op " " #val2)) \
661 log(__FILE__, __LINE__, \
662 @ac_google_namespace@::CheckOpString(_result)).stream()
664 // In optimized mode, use CheckOpString to hint to compiler that
665 // the while condition is unlikely.
666 #define CHECK_OP_LOG(name, op, val1, val2, log) \
667 while (@ac_google_namespace@::CheckOpString _result = \
668 @ac_google_namespace@::Check##name##Impl( \
669 @ac_google_namespace@::GetReferenceableValue(val1), \
670 @ac_google_namespace@::GetReferenceableValue(val2), \
671 #val1 " " #op " " #val2)) \
672 log(__FILE__, __LINE__, _result).stream()
673 #endif // STATIC_ANALYSIS, !NDEBUG
675 #if GOOGLE_STRIP_LOG <= 3
676 #define CHECK_OP(name, op, val1, val2) \
677 CHECK_OP_LOG(name, op, val1, val2, @ac_google_namespace@::LogMessageFatal)
679 #define CHECK_OP(name, op, val1, val2) \
680 CHECK_OP_LOG(name, op, val1, val2, @ac_google_namespace@::NullStreamFatal)
681 #endif // STRIP_LOG <= 3
683 // Equality/Inequality checks - compare two values, and log a FATAL message
684 // including the two values when the result is not as expected. The values
685 // must have operator<<(ostream, ...) defined.
687 // You may append to the error message like so:
688 // CHECK_NE(1, 2) << ": The world must be ending!";
690 // We are very careful to ensure that each argument is evaluated exactly
691 // once, and that anything which is legal to pass as a function argument is
692 // legal here. In particular, the arguments may be temporary expressions
693 // which will end up being destroyed at the end of the apparent statement,
695 // CHECK_EQ(string("abc")[1], 'b');
697 // WARNING: These don't compile correctly if one of the arguments is a pointer
698 // and the other is NULL. To work around this, simply static_cast NULL to the
699 // type of the desired pointer.
701 #define CHECK_EQ(val1, val2) CHECK_OP(_EQ, ==, val1, val2)
702 #define CHECK_NE(val1, val2) CHECK_OP(_NE, !=, val1, val2)
703 #define CHECK_LE(val1, val2) CHECK_OP(_LE, <=, val1, val2)
704 #define CHECK_LT(val1, val2) CHECK_OP(_LT, < , val1, val2)
705 #define CHECK_GE(val1, val2) CHECK_OP(_GE, >=, val1, val2)
706 #define CHECK_GT(val1, val2) CHECK_OP(_GT, > , val1, val2)
708 // Check that the input is non NULL. This very useful in constructor
709 // initializer lists.
711 #define CHECK_NOTNULL(val) \
712 @ac_google_namespace@::CheckNotNull(__FILE__, __LINE__, "'" #val "' Must be non NULL", (val))
714 // Helper functions for string comparisons.
715 // To avoid bloat, the definitions are in logging.cc.
716 #define DECLARE_CHECK_STROP_IMPL(func, expected) \
717 GOOGLE_GLOG_DLL_DECL std::string* Check##func##expected##Impl( \
718 const char* s1, const char* s2, const char* names);
719 DECLARE_CHECK_STROP_IMPL(strcmp, true)
720 DECLARE_CHECK_STROP_IMPL(strcmp, false)
721 DECLARE_CHECK_STROP_IMPL(strcasecmp, true)
722 DECLARE_CHECK_STROP_IMPL(strcasecmp, false)
723 #undef DECLARE_CHECK_STROP_IMPL
725 // Helper macro for string comparisons.
726 // Don't use this macro directly in your code, use CHECK_STREQ et al below.
727 #define CHECK_STROP(func, op, expected, s1, s2) \
728 while (@ac_google_namespace@::CheckOpString _result = \
729 @ac_google_namespace@::Check##func##expected##Impl((s1), (s2), \
730 #s1 " " #op " " #s2)) \
731 LOG(FATAL) << *_result.str_
734 // String (char*) equality/inequality checks.
735 // CASE versions are case-insensitive.
737 // Note that "s1" and "s2" may be temporary strings which are destroyed
738 // by the compiler at the end of the current "full expression"
739 // (e.g. CHECK_STREQ(Foo().c_str(), Bar().c_str())).
741 #define CHECK_STREQ(s1, s2) CHECK_STROP(strcmp, ==, true, s1, s2)
742 #define CHECK_STRNE(s1, s2) CHECK_STROP(strcmp, !=, false, s1, s2)
743 #define CHECK_STRCASEEQ(s1, s2) CHECK_STROP(strcasecmp, ==, true, s1, s2)
744 #define CHECK_STRCASENE(s1, s2) CHECK_STROP(strcasecmp, !=, false, s1, s2)
746 #define CHECK_INDEX(I,A) CHECK(I < (sizeof(A)/sizeof(A[0])))
747 #define CHECK_BOUND(B,A) CHECK(B <= (sizeof(A)/sizeof(A[0])))
749 #define CHECK_DOUBLE_EQ(val1, val2) \
751 CHECK_LE((val1), (val2)+0.000000000000001L); \
752 CHECK_GE((val1), (val2)-0.000000000000001L); \
755 #define CHECK_NEAR(val1, val2, margin) \
757 CHECK_LE((val1), (val2)+(margin)); \
758 CHECK_GE((val1), (val2)-(margin)); \
761 // perror()..googly style!
763 // PLOG() and PLOG_IF() and PCHECK() behave exactly like their LOG* and
764 // CHECK equivalents with the addition that they postpend a description
765 // of the current state of errno to their output lines.
767 #define PLOG(severity) GOOGLE_PLOG(severity, 0).stream()
769 #define GOOGLE_PLOG(severity, counter) \
770 @ac_google_namespace@::ErrnoLogMessage( \
771 __FILE__, __LINE__, @ac_google_namespace@::severity, counter, \
772 &@ac_google_namespace@::LogMessage::SendToLog)
774 #define PLOG_IF(severity, condition) \
775 !(condition) ? (void) 0 : @ac_google_namespace@::LogMessageVoidify() & PLOG(severity)
777 // A CHECK() macro that postpends errno if the condition is false. E.g.
779 // if (poll(fds, nfds, timeout) == -1) { PCHECK(errno == EINTR); ... }
780 #define PCHECK(condition) \
781 PLOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN(!(condition))) \
782 << "Check failed: " #condition " "
784 // A CHECK() macro that lets you assert the success of a function that
785 // returns -1 and sets errno in case of an error. E.g.
787 // CHECK_ERR(mkdir(path, 0700));
791 // int fd = open(filename, flags); CHECK_ERR(fd) << ": open " << filename;
792 #define CHECK_ERR(invocation) \
793 PLOG_IF(FATAL, GOOGLE_PREDICT_BRANCH_NOT_TAKEN((invocation) == -1)) \
796 // Use macro expansion to create, for each use of LOG_EVERY_N(), static
797 // variables with the __LINE__ expansion as part of the variable name.
798 #define LOG_EVERY_N_VARNAME(base, line) LOG_EVERY_N_VARNAME_CONCAT(base, line)
799 #define LOG_EVERY_N_VARNAME_CONCAT(base, line) base ## line
801 #define LOG_OCCURRENCES LOG_EVERY_N_VARNAME(occurrences_, __LINE__)
802 #define LOG_OCCURRENCES_MOD_N LOG_EVERY_N_VARNAME(occurrences_mod_n_, __LINE__)
804 #define SOME_KIND_OF_LOG_EVERY_N(severity, n, what_to_do) \
805 static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0; \
807 if (++LOG_OCCURRENCES_MOD_N > n) LOG_OCCURRENCES_MOD_N -= n; \
808 if (LOG_OCCURRENCES_MOD_N == 1) \
809 @ac_google_namespace@::LogMessage( \
810 __FILE__, __LINE__, @ac_google_namespace@::severity, LOG_OCCURRENCES, \
811 &what_to_do).stream()
813 #define SOME_KIND_OF_LOG_IF_EVERY_N(severity, condition, n, what_to_do) \
814 static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0; \
817 ((LOG_OCCURRENCES_MOD_N=(LOG_OCCURRENCES_MOD_N + 1) % n) == (1 % n))) \
818 @ac_google_namespace@::LogMessage( \
819 __FILE__, __LINE__, @ac_google_namespace@::severity, LOG_OCCURRENCES, \
820 &what_to_do).stream()
822 #define SOME_KIND_OF_PLOG_EVERY_N(severity, n, what_to_do) \
823 static int LOG_OCCURRENCES = 0, LOG_OCCURRENCES_MOD_N = 0; \
825 if (++LOG_OCCURRENCES_MOD_N > n) LOG_OCCURRENCES_MOD_N -= n; \
826 if (LOG_OCCURRENCES_MOD_N == 1) \
827 @ac_google_namespace@::ErrnoLogMessage( \
828 __FILE__, __LINE__, @ac_google_namespace@::severity, LOG_OCCURRENCES, \
829 &what_to_do).stream()
831 #define SOME_KIND_OF_LOG_FIRST_N(severity, n, what_to_do) \
832 static int LOG_OCCURRENCES = 0; \
833 if (LOG_OCCURRENCES <= n) \
835 if (LOG_OCCURRENCES <= n) \
836 @ac_google_namespace@::LogMessage( \
837 __FILE__, __LINE__, @ac_google_namespace@::severity, LOG_OCCURRENCES, \
838 &what_to_do).stream()
840 namespace glog_internal_namespace_ {
842 struct CompileAssert {
845 } // namespace glog_internal_namespace_
847 #define GOOGLE_GLOG_COMPILE_ASSERT(expr, msg) \
848 typedef @ac_google_namespace@::glog_internal_namespace_::CompileAssert<(bool(expr))> msg[bool(expr) ? 1 : -1]
850 #define LOG_EVERY_N(severity, n) \
851 GOOGLE_GLOG_COMPILE_ASSERT(@ac_google_namespace@::severity < \
852 @ac_google_namespace@::NUM_SEVERITIES, \
853 INVALID_REQUESTED_LOG_SEVERITY); \
854 SOME_KIND_OF_LOG_EVERY_N(severity, (n), @ac_google_namespace@::LogMessage::SendToLog)
856 #define SYSLOG_EVERY_N(severity, n) \
857 SOME_KIND_OF_LOG_EVERY_N(severity, (n), @ac_google_namespace@::LogMessage::SendToSyslogAndLog)
859 #define PLOG_EVERY_N(severity, n) \
860 SOME_KIND_OF_PLOG_EVERY_N(severity, (n), @ac_google_namespace@::LogMessage::SendToLog)
862 #define LOG_FIRST_N(severity, n) \
863 SOME_KIND_OF_LOG_FIRST_N(severity, (n), @ac_google_namespace@::LogMessage::SendToLog)
865 #define LOG_IF_EVERY_N(severity, condition, n) \
866 SOME_KIND_OF_LOG_IF_EVERY_N(severity, (condition), (n), @ac_google_namespace@::LogMessage::SendToLog)
868 // We want the special COUNTER value available for LOG_EVERY_X()'ed messages
869 enum PRIVATE_Counter {COUNTER};
872 // Plus some debug-logging macros that get compiled to nothing for production
876 #define DLOG(severity) LOG(severity)
877 #define DVLOG(verboselevel) VLOG(verboselevel)
878 #define DLOG_IF(severity, condition) LOG_IF(severity, condition)
879 #define DLOG_EVERY_N(severity, n) LOG_EVERY_N(severity, n)
880 #define DLOG_IF_EVERY_N(severity, condition, n) \
881 LOG_IF_EVERY_N(severity, condition, n)
882 #define DLOG_ASSERT(condition) LOG_ASSERT(condition)
884 // debug-only checking. not executed in NDEBUG mode.
885 #define DCHECK(condition) CHECK(condition)
886 #define DCHECK_EQ(val1, val2) CHECK_EQ(val1, val2)
887 #define DCHECK_NE(val1, val2) CHECK_NE(val1, val2)
888 #define DCHECK_LE(val1, val2) CHECK_LE(val1, val2)
889 #define DCHECK_LT(val1, val2) CHECK_LT(val1, val2)
890 #define DCHECK_GE(val1, val2) CHECK_GE(val1, val2)
891 #define DCHECK_GT(val1, val2) CHECK_GT(val1, val2)
892 #define DCHECK_STREQ(str1, str2) CHECK_STREQ(str1, str2)
893 #define DCHECK_STRCASEEQ(str1, str2) CHECK_STRCASEEQ(str1, str2)
894 #define DCHECK_STRNE(str1, str2) CHECK_STRNE(str1, str2)
895 #define DCHECK_STRCASENE(str1, str2) CHECK_STRCASENE(str1, str2)
899 #define DLOG(severity) \
900 true ? (void) 0 : @ac_google_namespace@::LogMessageVoidify() & LOG(severity)
902 #define DVLOG(verboselevel) \
903 (true || !VLOG_IS_ON(verboselevel)) ?\
904 (void) 0 : @ac_google_namespace@::LogMessageVoidify() & LOG(INFO)
906 #define DLOG_IF(severity, condition) \
907 (true || !(condition)) ? (void) 0 : @ac_google_namespace@::LogMessageVoidify() & LOG(severity)
909 #define DLOG_EVERY_N(severity, n) \
910 true ? (void) 0 : @ac_google_namespace@::LogMessageVoidify() & LOG(severity)
912 #define DLOG_IF_EVERY_N(severity, condition, n) \
913 (true || !(condition))? (void) 0 : @ac_google_namespace@::LogMessageVoidify() & LOG(severity)
915 #define DLOG_ASSERT(condition) \
916 true ? (void) 0 : LOG_ASSERT(condition)
918 #define DCHECK(condition) \
922 #define DCHECK_EQ(val1, val2) \
926 #define DCHECK_NE(val1, val2) \
930 #define DCHECK_LE(val1, val2) \
934 #define DCHECK_LT(val1, val2) \
938 #define DCHECK_GE(val1, val2) \
942 #define DCHECK_GT(val1, val2) \
946 #define DCHECK_STREQ(str1, str2) \
948 CHECK_STREQ(str1, str2)
950 #define DCHECK_STRCASEEQ(str1, str2) \
952 CHECK_STRCASEEQ(str1, str2)
954 #define DCHECK_STRNE(str1, str2) \
956 CHECK_STRNE(str1, str2)
958 #define DCHECK_STRCASENE(str1, str2) \
960 CHECK_STRCASENE(str1, str2)
965 // Log only in verbose mode.
967 #define VLOG(verboselevel) LOG_IF(INFO, VLOG_IS_ON(verboselevel))
969 #define VLOG_IF(verboselevel, condition) \
970 LOG_IF(INFO, (condition) && VLOG_IS_ON(verboselevel))
972 #define VLOG_EVERY_N(verboselevel, n) \
973 LOG_IF_EVERY_N(INFO, VLOG_IS_ON(verboselevel), n)
975 #define VLOG_IF_EVERY_N(verboselevel, condition, n) \
976 LOG_IF_EVERY_N(INFO, (condition) && VLOG_IS_ON(verboselevel), n)
979 // This class more or less represents a particular log message. You
980 // create an instance of LogMessage and then stream stuff to it.
981 // When you finish streaming to it, ~LogMessage is called and the
982 // full message gets streamed to the appropriate destination.
984 // You shouldn't actually use LogMessage's constructor to log things,
985 // though. You should use the LOG() macro (and variants thereof)
987 class GOOGLE_GLOG_DLL_DECL LogMessage {
990 // Passing kNoLogPrefix for the line number disables the
991 // log-message prefix. Useful for using the LogMessage
992 // infrastructure as a printing utility. See also the --log_prefix
993 // flag for controlling the log-message prefix on an
994 // application-wide basis.
998 // LogStream inherit from non-DLL-exported class (std::ostrstream)
999 // and VC++ produces a warning for this situation.
1000 // However, MSDN says "C4275 can be ignored in Microsoft Visual C++
1001 // 2005 if you are deriving from a type in the Standard C++ Library"
1002 // http://msdn.microsoft.com/en-us/library/3tdb471s(VS.80).aspx
1003 // Let's just ignore the warning.
1005 # pragma warning(disable: 4275)
1007 class GOOGLE_GLOG_DLL_DECL LogStream : public std::ostrstream {
1009 # pragma warning(default: 4275)
1012 LogStream(char *buf, int len, int ctr)
1013 : ostrstream(buf, len),
1018 int ctr() const { return ctr_; }
1019 void set_ctr(int ctr) { ctr_ = ctr; }
1020 LogStream* self() const { return self_; }
1023 int ctr_; // Counter hack (for the LOG_EVERY_X() macro)
1024 LogStream *self_; // Consistency check hack
1028 // icc 8 requires this typedef to avoid an internal compiler error.
1029 typedef void (LogMessage::*SendMethod)();
1031 LogMessage(const char* file, int line, LogSeverity severity, int ctr,
1032 SendMethod send_method);
1034 // Two special constructors that generate reduced amounts of code at
1035 // LOG call sites for common cases.
1037 // Used for LOG(INFO): Implied are:
1038 // severity = INFO, ctr = 0, send_method = &LogMessage::SendToLog.
1040 // Using this constructor instead of the more complex constructor above
1041 // saves 19 bytes per call site.
1042 LogMessage(const char* file, int line);
1044 // Used for LOG(severity) where severity != INFO. Implied
1045 // are: ctr = 0, send_method = &LogMessage::SendToLog
1047 // Using this constructor instead of the more complex constructor above
1048 // saves 17 bytes per call site.
1049 LogMessage(const char* file, int line, LogSeverity severity);
1051 // Constructor to log this message to a specified sink (if not NULL).
1052 // Implied are: ctr = 0, send_method = &LogMessage::SendToSinkAndLog if
1053 // also_send_to_log is true, send_method = &LogMessage::SendToSink otherwise.
1054 LogMessage(const char* file, int line, LogSeverity severity, LogSink* sink,
1055 bool also_send_to_log);
1057 // Constructor where we also give a vector<string> pointer
1058 // for storing the messages (if the pointer is not NULL).
1059 // Implied are: ctr = 0, send_method = &LogMessage::SaveOrSendToLog.
1060 LogMessage(const char* file, int line, LogSeverity severity,
1061 std::vector<std::string>* outvec);
1063 // Constructor where we also give a string pointer for storing the
1064 // message (if the pointer is not NULL). Implied are: ctr = 0,
1065 // send_method = &LogMessage::WriteToStringAndLog.
1066 LogMessage(const char* file, int line, LogSeverity severity,
1067 std::string* message);
1069 // A special constructor used for check failures
1070 LogMessage(const char* file, int line, const CheckOpString& result);
1074 // Flush a buffered message to the sink set in the constructor. Always
1075 // called by the destructor, it may also be called from elsewhere if
1076 // needed. Only the first call is actioned; any later ones are ignored.
1079 // An arbitrary limit on the length of a single log message. This
1080 // is so that streaming can be done more efficiently.
1081 static const size_t kMaxLogMessageLen;
1083 // Theses should not be called directly outside of logging.*,
1084 // only passed as SendMethod arguments to other LogMessage methods:
1085 void SendToLog(); // Actually dispatch to the logs
1086 void SendToSyslogAndLog(); // Actually dispatch to syslog and the logs
1088 // Call abort() or similar to perform LOG(FATAL) crash.
1089 static void Fail() @ac_cv___attribute___noreturn@;
1091 std::ostream& stream() { return *(data_->stream_); }
1093 int preserved_errno() const { return data_->preserved_errno_; }
1095 // Must be called without the log_mutex held. (L < log_mutex)
1096 static int64 num_messages(int severity);
1099 // Fully internal SendMethod cases:
1100 void SendToSinkAndLog(); // Send to sink if provided and dispatch to the logs
1101 void SendToSink(); // Send to sink if provided, do nothing otherwise.
1103 // Write to string if provided and dispatch to the logs.
1104 void WriteToStringAndLog();
1106 void SaveOrSendToLog(); // Save to stringvec if provided, else to logs
1108 void Init(const char* file, int line, LogSeverity severity,
1109 void (LogMessage::*send_method)());
1111 // Used to fill in crash information during LOG(FATAL) failures.
1112 void RecordCrashReason(glog_internal_namespace_::CrashReason* reason);
1114 // Counts of messages sent at each priority:
1115 static int64 num_messages_[NUM_SEVERITIES]; // under log_mutex
1117 // We keep the data in a separate struct so that each instance of
1118 // LogMessage uses less stack space.
1119 struct GOOGLE_GLOG_DLL_DECL LogMessageData {
1120 LogMessageData() {};
1122 int preserved_errno_; // preserved errno
1124 char* message_text_; // Complete message text (points to selected buffer)
1125 LogStream* stream_alloc_;
1127 char severity_; // What level is this LogMessage logged at?
1128 int line_; // line number where logging call is.
1129 void (LogMessage::*send_method_)(); // Call this in destructor to send
1130 union { // At most one of these is used: union to keep the size low.
1131 LogSink* sink_; // NULL or sink to send message to
1132 std::vector<std::string>* outvec_; // NULL or vector to push message onto
1133 std::string* message_; // NULL or string to write message into
1135 time_t timestamp_; // Time of creation of LogMessage
1136 struct ::tm tm_time_; // Time of creation of LogMessage
1137 size_t num_prefix_chars_; // # of chars of prefix in this message
1138 size_t num_chars_to_log_; // # of chars of msg to send to log
1139 size_t num_chars_to_syslog_; // # of chars of msg to send to syslog
1140 const char* basename_; // basename of file that called LOG
1141 const char* fullname_; // fullname of file that called LOG
1142 bool has_been_flushed_; // false => data has not been flushed
1143 bool first_fatal_; // true => this was first fatal msg
1147 LogMessageData(const LogMessageData&);
1148 void operator=(const LogMessageData&);
1151 static LogMessageData fatal_msg_data_exclusive_;
1152 static LogMessageData fatal_msg_data_shared_;
1154 LogMessageData* allocated_;
1155 LogMessageData* data_;
1157 friend class LogDestination;
1159 LogMessage(const LogMessage&);
1160 void operator=(const LogMessage&);
1163 // This class happens to be thread-hostile because all instances share
1164 // a single data buffer, but since it can only be created just before
1165 // the process dies, we don't worry so much.
1166 class GOOGLE_GLOG_DLL_DECL LogMessageFatal : public LogMessage {
1168 LogMessageFatal(const char* file, int line);
1169 LogMessageFatal(const char* file, int line, const CheckOpString& result);
1170 ~LogMessageFatal() @ac_cv___attribute___noreturn@;
1173 // A non-macro interface to the log facility; (useful
1174 // when the logging level is not a compile-time constant).
1175 inline void LogAtLevel(int const severity, std::string const &msg) {
1176 LogMessage(__FILE__, __LINE__, severity).stream() << msg;
1179 // A macro alternative of LogAtLevel. New code may want to use this
1180 // version since there are two advantages: 1. this version outputs the
1181 // file name and the line number where this macro is put like other
1182 // LOG macros, 2. this macro can be used as C++ stream.
1183 #define LOG_AT_LEVEL(severity) @ac_google_namespace@::LogMessage(__FILE__, __LINE__, severity).stream()
1185 // A small helper for CHECK_NOTNULL().
1186 template <typename T>
1187 T* CheckNotNull(const char *file, int line, const char *names, T* t) {
1189 LogMessageFatal(file, line, new std::string(names));
1194 // Allow folks to put a counter in the LOG_EVERY_X()'ed messages. This
1195 // only works if ostream is a LogStream. If the ostream is not a
1196 // LogStream you'll get an assert saying as much at runtime.
1197 GOOGLE_GLOG_DLL_DECL std::ostream& operator<<(std::ostream &os,
1198 const PRIVATE_Counter&);
1201 // Derived class for PLOG*() above.
1202 class GOOGLE_GLOG_DLL_DECL ErrnoLogMessage : public LogMessage {
1205 ErrnoLogMessage(const char* file, int line, LogSeverity severity, int ctr,
1206 void (LogMessage::*send_method)());
1208 // Postpends ": strerror(errno) [errno]".
1212 ErrnoLogMessage(const ErrnoLogMessage&);
1213 void operator=(const ErrnoLogMessage&);
1217 // This class is used to explicitly ignore values in the conditional
1218 // logging macros. This avoids compiler warnings like "value computed
1219 // is not used" and "statement has no effect".
1221 class GOOGLE_GLOG_DLL_DECL LogMessageVoidify {
1223 LogMessageVoidify() { }
1224 // This has to be an operator with a precedence lower than << but
1226 void operator&(std::ostream&) { }
1230 // Flushes all log files that contains messages that are at least of
1231 // the specified severity level. Thread-safe.
1232 GOOGLE_GLOG_DLL_DECL void FlushLogFiles(LogSeverity min_severity);
1234 // Flushes all log files that contains messages that are at least of
1235 // the specified severity level. Thread-hostile because it ignores
1236 // locking -- used for catastrophic failures.
1237 GOOGLE_GLOG_DLL_DECL void FlushLogFilesUnsafe(LogSeverity min_severity);
1240 // Set the destination to which a particular severity level of log
1241 // messages is sent. If base_filename is "", it means "don't log this
1242 // severity". Thread-safe.
1244 GOOGLE_GLOG_DLL_DECL void SetLogDestination(LogSeverity severity,
1245 const char* base_filename);
1248 // Set the basename of the symlink to the latest log file at a given
1249 // severity. If symlink_basename is empty, do not make a symlink. If
1250 // you don't call this function, the symlink basename is the
1251 // invocation name of the program. Thread-safe.
1253 GOOGLE_GLOG_DLL_DECL void SetLogSymlink(LogSeverity severity,
1254 const char* symlink_basename);
1257 // Used to send logs to some other kind of destination
1258 // Users should subclass LogSink and override send to do whatever they want.
1259 // Implementations must be thread-safe because a shared instance will
1260 // be called from whichever thread ran the LOG(XXX) line.
1261 class GOOGLE_GLOG_DLL_DECL LogSink {
1265 // Sink's logging logic (message_len is such as to exclude '\n' at the end).
1266 // This method can't use LOG() or CHECK() as logging system mutex(s) are held
1267 // during this call.
1268 virtual void send(LogSeverity severity, const char* full_filename,
1269 const char* base_filename, int line,
1270 const struct ::tm* tm_time,
1271 const char* message, size_t message_len) = 0;
1273 // Redefine this to implement waiting for
1274 // the sink's logging logic to complete.
1275 // It will be called after each send() returns,
1276 // but before that LogMessage exits or crashes.
1277 // By default this function does nothing.
1278 // Using this function one can implement complex logic for send()
1279 // that itself involves logging; and do all this w/o causing deadlocks and
1280 // inconsistent rearrangement of log messages.
1281 // E.g. if a LogSink has thread-specific actions, the send() method
1282 // can simply add the message to a queue and wake up another thread that
1283 // handles real logging while itself making some LOG() calls;
1284 // WaitTillSent() can be implemented to wait for that logic to complete.
1285 // See our unittest for an example.
1286 virtual void WaitTillSent();
1288 // Returns the normal text output of the log message.
1289 // Can be useful to implement send().
1290 static std::string ToString(LogSeverity severity, const char* file, int line,
1291 const struct ::tm* tm_time,
1292 const char* message, size_t message_len);
1295 // Add or remove a LogSink as a consumer of logging data. Thread-safe.
1296 GOOGLE_GLOG_DLL_DECL void AddLogSink(LogSink *destination);
1297 GOOGLE_GLOG_DLL_DECL void RemoveLogSink(LogSink *destination);
1300 // Specify an "extension" added to the filename specified via
1301 // SetLogDestination. This applies to all severity levels. It's
1302 // often used to append the port we're listening on to the logfile
1303 // name. Thread-safe.
1305 GOOGLE_GLOG_DLL_DECL void SetLogFilenameExtension(
1306 const char* filename_extension);
1309 // Make it so that all log messages of at least a particular severity
1310 // are logged to stderr (in addition to logging to the usual log
1311 // file(s)). Thread-safe.
1313 GOOGLE_GLOG_DLL_DECL void SetStderrLogging(LogSeverity min_severity);
1316 // Make it so that all log messages go only to stderr. Thread-safe.
1318 GOOGLE_GLOG_DLL_DECL void LogToStderr();
1321 // Make it so that all log messages of at least a particular severity are
1322 // logged via email to a list of addresses (in addition to logging to the
1323 // usual log file(s)). The list of addresses is just a string containing
1324 // the email addresses to send to (separated by spaces, say). Thread-safe.
1326 GOOGLE_GLOG_DLL_DECL void SetEmailLogging(LogSeverity min_severity,
1327 const char* addresses);
1329 // A simple function that sends email. dest is a commma-separated
1330 // list of addressess. Thread-safe.
1331 GOOGLE_GLOG_DLL_DECL bool SendEmail(const char *dest,
1332 const char *subject, const char *body);
1334 GOOGLE_GLOG_DLL_DECL const std::vector<std::string>& GetLoggingDirectories();
1336 // For tests only: Clear the internal [cached] list of logging directories to
1337 // force a refresh the next time GetLoggingDirectories is called.
1339 void TestOnly_ClearLoggingDirectoriesList();
1341 // Returns a set of existing temporary directories, which will be a
1342 // subset of the directories returned by GetLogginDirectories().
1344 GOOGLE_GLOG_DLL_DECL void GetExistingTempDirectories(
1345 std::vector<std::string>* list);
1347 // Print any fatal message again -- useful to call from signal handler
1348 // so that the last thing in the output is the fatal message.
1349 // Thread-hostile, but a race is unlikely.
1350 GOOGLE_GLOG_DLL_DECL void ReprintFatalMessage();
1352 // Truncate a log file that may be the append-only output of multiple
1353 // processes and hence can't simply be renamed/reopened (typically a
1354 // stdout/stderr). If the file "path" is > "limit" bytes, copy the
1355 // last "keep" bytes to offset 0 and truncate the rest. Since we could
1356 // be racing with other writers, this approach has the potential to
1357 // lose very small amounts of data. For security, only follow symlinks
1358 // if the path is /proc/self/fd/*
1359 GOOGLE_GLOG_DLL_DECL void TruncateLogFile(const char *path,
1360 int64 limit, int64 keep);
1362 // Truncate stdout and stderr if they are over the value specified by
1363 // --max_log_size; keep the final 1MB. This function has the same
1364 // race condition as TruncateLogFile.
1365 GOOGLE_GLOG_DLL_DECL void TruncateStdoutStderr();
1367 // Return the string representation of the provided LogSeverity level.
1369 GOOGLE_GLOG_DLL_DECL const char* GetLogSeverityName(LogSeverity severity);
1371 // ---------------------------------------------------------------------
1372 // Implementation details that are not useful to most clients
1373 // ---------------------------------------------------------------------
1375 // A Logger is the interface used by logging modules to emit entries
1376 // to a log. A typical implementation will dump formatted data to a
1377 // sequence of files. We also provide interfaces that will forward
1378 // the data to another thread so that the invoker never blocks.
1379 // Implementations should be thread-safe since the logging system
1380 // will write to them from multiple threads.
1384 class GOOGLE_GLOG_DLL_DECL Logger {
1388 // Writes "message[0,message_len-1]" corresponding to an event that
1389 // occurred at "timestamp". If "force_flush" is true, the log file
1390 // is flushed immediately.
1392 // The input message has already been formatted as deemed
1393 // appropriate by the higher level logging facility. For example,
1394 // textual log messages already contain timestamps, and the
1395 // file:linenumber header.
1396 virtual void Write(bool force_flush,
1398 const char* message,
1399 int message_len) = 0;
1401 // Flush any buffered messages
1402 virtual void Flush() = 0;
1404 // Get the current LOG file size.
1405 // The returned value is approximate since some
1406 // logged data may not have been flushed to disk yet.
1407 virtual uint32 LogSize() = 0;
1410 // Get the logger for the specified severity level. The logger
1411 // remains the property of the logging module and should not be
1412 // deleted by the caller. Thread-safe.
1413 extern GOOGLE_GLOG_DLL_DECL Logger* GetLogger(LogSeverity level);
1415 // Set the logger for the specified severity level. The logger
1416 // becomes the property of the logging module and should not
1417 // be deleted by the caller. Thread-safe.
1418 extern GOOGLE_GLOG_DLL_DECL void SetLogger(LogSeverity level, Logger* logger);
1422 // glibc has traditionally implemented two incompatible versions of
1423 // strerror_r(). There is a poorly defined convention for picking the
1424 // version that we want, but it is not clear whether it even works with
1425 // all versions of glibc.
1426 // So, instead, we provide this wrapper that automatically detects the
1427 // version that is in use, and then implements POSIX semantics.
1428 // N.B. In addition to what POSIX says, we also guarantee that "buf" will
1429 // be set to an empty string, if this function failed. This means, in most
1430 // cases, you do not need to check the error code and you can directly
1431 // use the value of "buf". It will never have an undefined value.
1432 GOOGLE_GLOG_DLL_DECL int posix_strerror_r(int err, char *buf, size_t len);
1435 // A class for which we define operator<<, which does nothing.
1436 class GOOGLE_GLOG_DLL_DECL NullStream : public LogMessage::LogStream {
1438 // Initialize the LogStream so the messages can be written somewhere
1439 // (they'll never be actually displayed). This will be needed if a
1440 // NullStream& is implicitly converted to LogStream&, in which case
1441 // the overloaded NullStream::operator<< will not be invoked.
1442 NullStream() : LogMessage::LogStream(message_buffer_, 1, 0) { }
1443 NullStream(const char* /*file*/, int /*line*/,
1444 const CheckOpString& /*result*/) :
1445 LogMessage::LogStream(message_buffer_, 1, 0) { }
1446 NullStream &stream() { return *this; }
1448 // A very short buffer for messages (which we discard anyway). This
1449 // will be needed if NullStream& converted to LogStream& (e.g. as a
1450 // result of a conditional expression).
1451 char message_buffer_[2];
1454 // Do nothing. This operator is inline, allowing the message to be
1455 // compiled away. The message will not be compiled away if we do
1456 // something like (flag ? LOG(INFO) : LOG(ERROR)) << message; when
1457 // SKIP_LOG=WARNING. In those cases, NullStream will be implicitly
1458 // converted to LogStream and the message will be computed and then
1459 // quietly discarded.
1461 inline NullStream& operator<<(NullStream &str, const T &value) { return str; }
1463 // Similar to NullStream, but aborts the program (without stack
1464 // trace), like LogMessageFatal.
1465 class GOOGLE_GLOG_DLL_DECL NullStreamFatal : public NullStream {
1467 NullStreamFatal() { }
1468 NullStreamFatal(const char* file, int line, const CheckOpString& result) :
1469 NullStream(file, line, result) { }
1470 @ac_cv___attribute___noreturn@ ~NullStreamFatal() { _exit(1); }
1473 // Install a signal handler that will dump signal information and a stack
1474 // trace when the program crashes on certain signals. We'll install the
1475 // signal handler for the following signals.
1477 // SIGSEGV, SIGILL, SIGFPE, SIGABRT, SIGBUS, and SIGTERM.
1479 // By default, the signal handler will write the failure dump to the
1480 // standard error. You can customize the destination by installing your
1481 // own writer function by InstallFailureWriter() below.
1483 // Note on threading:
1485 // The function should be called before threads are created, if you want
1486 // to use the failure signal handler for all threads. The stack trace
1487 // will be shown only for the thread that receives the signal. In other
1488 // words, stack traces of other threads won't be shown.
1489 GOOGLE_GLOG_DLL_DECL void InstallFailureSignalHandler();
1491 // Installs a function that is used for writing the failure dump. "data"
1492 // is the pointer to the beginning of a message to be written, and "size"
1493 // is the size of the message. You should not expect the data is
1494 // terminated with '\0'.
1495 GOOGLE_GLOG_DLL_DECL void InstallFailureWriter(
1496 void (*writer)(const char* data, int size));
1498 @ac_google_end_namespace@
1500 #endif // _LOGGING_H_