summaryrefslogtreecommitdiff
path: root/indra/llcommon/llerror.h
blob: 6f6b349cf54c7b67043167c83fa68e86735a6658 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
/** 
 * @file llerror.h
 * @date   December 2006
 * @brief error message system
 *
 * $LicenseInfo:firstyear=2006&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_LLERROR_H
#define LL_LLERROR_H

#include <sstream>
#include <string>
#include <typeinfo>
#include <vector>

#include "stdtypes.h"

#include "llprofiler.h"
#include "llpreprocessor.h"

#include <boost/static_assert.hpp>
#include <functional> // std::function

const int LL_ERR_NOERR = 0;

// Define one of these for different error levels in release...
// #define RELEASE_SHOW_DEBUG // Define this if you want your release builds to show lldebug output.
#define RELEASE_SHOW_INFO // Define this if you want your release builds to show llinfo output
#define RELEASE_SHOW_WARN // Define this if you want your release builds to show llwarn output.

#ifdef _DEBUG
#define SHOW_DEBUG
#define SHOW_WARN
#define SHOW_INFO
#define SHOW_ASSERT
#else // _DEBUG

#ifdef LL_RELEASE_WITH_DEBUG_INFO
#define SHOW_ASSERT
#endif // LL_RELEASE_WITH_DEBUG_INFO

#ifdef RELEASE_SHOW_DEBUG
#define SHOW_DEBUG
#endif

#ifdef RELEASE_SHOW_WARN
#define SHOW_WARN
#endif

#ifdef RELEASE_SHOW_INFO
#define SHOW_INFO
#endif

#ifdef RELEASE_SHOW_ASSERT
#define SHOW_ASSERT
#endif

#endif // !_DEBUG

#define llassert_always_msg(func, msg) if (LL_UNLIKELY(!(func))) LL_ERRS() << "ASSERT (" << msg << ")" << LL_ENDL

#define llassert_always(func)	llassert_always_msg(func, #func)

#ifdef SHOW_ASSERT
#define llassert(func)			llassert_always_msg(func, #func)
#define llassert_msg(func, msg)	llassert_always_msg(func, msg)
#define llverify(func)			llassert_always_msg(func, #func)
#else
#define llassert(func)
#define llassert_msg(func, msg)
#define llverify(func)			do {if (func) {}} while(0)
#endif

#ifdef LL_WINDOWS
#define LL_STATIC_ASSERT(func, msg) static_assert(func, msg)
#define LL_BAD_TEMPLATE_INSTANTIATION(type, msg) static_assert(false, msg)
#else
#define LL_STATIC_ASSERT(func, msg) BOOST_STATIC_ASSERT(func)
#define LL_BAD_TEMPLATE_INSTANTIATION(type, msg) BOOST_STATIC_ASSERT(sizeof(type) != 0 && false);
#endif


/** Error Logging Facility

	Information for most users:
	
	Code can log messages with constructions like this:
	
		LL_INFOS("StringTag") << "request to fizzbip agent " << agent_id
			<< " denied due to timeout" << LL_ENDL;
		
	Messages can be logged to one of four increasing levels of concern,
	using one of four "streams":

		LL_DEBUGS("StringTag")	- debug messages that are normally suppressed
		LL_INFOS("StringTag")	- informational messages that are normal shown
		LL_WARNS("StringTag")	- warning messages that signal a problem
		LL_ERRS("StringTag")	- error messages that are major, unrecoverable failures
		
	The later (LL_ERRS("StringTag")) automatically crashes the process after the message
	is logged.
	
	Note that these "streams" are actually #define magic.  Rules for use:
		* they cannot be used as normal streams, only to start a message
		* messages written to them MUST be terminated with LL_ENDL
		* between the opening and closing, the << operator is indeed
		  writing onto a std::ostream, so all conversions and stream
		  formating are available
	
	These messages are automatically logged with function name, and (if enabled)
	file and line of the message.  (Note: Existing messages that already include
	the function name don't get name printed twice.)
	
	If you have a class, adding LOG_CLASS line to the declaration will cause
	all messages emitted from member functions (normal and static) to be tagged
	with the proper class name as well as the function name:
	
		class LLFoo
		{
			LOG_CLASS(LLFoo);
		public:
			...
		};
	
		void LLFoo::doSomething(int i)
		{
			if (i > 100)
			{
				LL_WARNS("FooBarTag") << "called with a big value for i: " << i << LL_ENDL; 
			}
			...
		}
	
	will result in messages like:
	
		WARN #FooBarTag# llcommon/llfoo(100) LLFoo::doSomething : called with a big value for i: 283
	
    the syntax is:
        <timestamp> SPACE <level> SPACE <tags> SPACE <location> SPACE <function> SPACE COLON SPACE <message>

    where each SPACE is a single space character; note that if a field is empty (such as when no
    tags are specified), all the SPACEs are still present.

    The tags must be a single word (may not contain a space); if more than one tag is specified,
    they are all surrounded by '#' ( #FooTag#BarTag# ).

	Which messages are logged and which are suppressed can be controlled at run
	time from the configuration file. The default configuration is in newview/app_settings/logcontrol.xml
    A copy of that file named logcontrol-dev.xml can be made in the users personal settings
    directory; that will override the installed default file.  See the logcontrol.xml
    file or http://wiki.secondlife.com/wiki/Logging_System_Overview for configuration details.
	
	Lastly, logging is now very efficient in both compiled code and execution
	when skipped.  There is no need to wrap messages, even debugging ones, in
	#ifdef _DEBUG constructs.  LL_DEBUGS("StringTag") messages are compiled into all builds,
	even release.  Which means you can use them to help debug even when deployed
	to a real grid.
*/
namespace LLError
{
	enum ELevel
	{
		LEVEL_ALL = 0,
			// used to indicate that all messages should be logged
			
		LEVEL_DEBUG = 0,
		LEVEL_INFO = 1,
		LEVEL_WARN = 2,
		LEVEL_ERROR = 3,	// used to be called FATAL
		
		LEVEL_NONE = 4
			// not really a level
			// used to indicate that no messages should be logged
	};
	// If you change ELevel, please update llvlog() macro below.

	/*	Macro support
		The classes CallSite and Log are used by the logging macros below.
		They are not intended for general use.
	*/

	struct CallSite;

	class LL_COMMON_API Log
	{
	public:
		static bool shouldLog(CallSite&);
		static void flush(const std::ostringstream&, const CallSite&);
		static std::string demangle(const char* mangled);
		/// classname<TYPE>()
		template <typename T>
		static std::string classname()             { return demangle(typeid(T).name()); }
		/// classname(some_pointer)
		template <typename T>
		static std::string classname(T* const ptr) { return ptr? demangle(typeid(*ptr).name()) : "nullptr"; }
		/// classname(some_reference)
		template <typename T>
		static std::string classname(const T& obj) { return demangle(typeid(obj).name()); }
	};

	struct LL_COMMON_API CallSite
	{
		// Represents a specific place in the code where a message is logged
		// This is public because it is used by the macros below.  It is not
		// intended for public use.
		CallSite(ELevel level, 
				const char* file, 
				int line,
				const std::type_info& class_info, 
				const char* function, 
				bool print_once, 
				const char** tags, 
				size_t tag_count);

		~CallSite();

#ifdef LL_LIBRARY_INCLUDE
		bool shouldLog();
#else // LL_LIBRARY_INCLUDE
		bool shouldLog()
		{ 
			return mCached 
					? mShouldLog 
					: Log::shouldLog(*this); 
		}
			// this member function needs to be in-line for efficiency
#endif // LL_LIBRARY_INCLUDE
		
		void invalidate();
		
		// these describe the call site and never change
		const ELevel			mLevel;
		const char* const		mFile;
		const int				mLine;
		const std::type_info&   mClassInfo;
		const char* const		mFunction;
		const char**			mTags;
		size_t					mTagCount;
		const bool				mPrintOnce;
		const char*				mLevelString;
		std::string				mLocationString,
								mFunctionString,
								mTagString;
		bool					mCached,
								mShouldLog;
		
		friend class Log;
	};
	
	
	class End { };
	inline std::ostream& operator<<(std::ostream& s, const End&)
		{ return s; }
		// used to indicate the end of a message
		
	class LL_COMMON_API NoClassInfo { };
		// used to indicate no class info known for logging

    //LLCallStacks keeps track of call stacks and output the call stacks to log file
    //
    //Note: to be simple, efficient and necessary to keep track of correct call stacks, 
    //LLCallStacks is designed not to be thread-safe.
    //so try not to use it in multiple parallel threads at same time.
    //Used in a single thread at a time is fine.
    class LL_COMMON_API LLCallStacks
    {
    private:
        typedef std::vector<std::string> StringVector;
        static StringVector sBuffer ;
              
    public:   
        static void push(const char* function, const int line) ;
        static void insert(std::ostream& out, const char* function, const int line) ;
        static void print() ;
        static void clear() ;
        static void end(const std::ostringstream& out) ;
        static void cleanup();
    };

    // class which, when streamed, inserts the current stack trace
    struct LLStacktrace
    {
        friend std::ostream& operator<<(std::ostream& out, const LLStacktrace&);
    };

    // Provides access to OS notification popup on error, since
    // not everything has access to OS's messages
    class LLUserWarningMsg
    {
    public:
        typedef std::function<void(const std::string&, const std::string&)> Handler;
        static void setHandler(const Handler&);
        static void setOutOfMemoryStrings(const std::string& title, const std::string& message);

        // When viewer encounters bad alloc or can't access files try warning user about reasons
        static void showOutOfMemory();
        static void showMissingFiles();
        // Genering error
        static void show(const std::string&);

    private:
        // needs to be preallocated before viewer runs out of memory
        static std::string sLocalizedOutOfMemoryTitle;
        static std::string sLocalizedOutOfMemoryWarning;
        static Handler sHandler;
    };
}

//this is cheaper than llcallstacks if no need to output other variables to call stacks. 
#define LL_PUSH_CALLSTACKS() LLError::LLCallStacks::push(__FUNCTION__, __LINE__)

#define llcallstacks                                                    \
	{                                                                   \
		std::ostringstream _out;                                        \
		LLError::LLCallStacks::insert(_out, __FUNCTION__, __LINE__) ;   \
		_out

#define llcallstacksendl                   \
		LLError::End();                    \
		LLError::LLCallStacks::end(_out) ; \
	}

#define LL_CLEAR_CALLSTACKS() LLError::LLCallStacks::clear()
#define LL_PRINT_CALLSTACKS() LLError::LLCallStacks::print() 

/*
	Class type information for logging
 */

#define LOG_CLASS(s)	typedef s _LL_CLASS_TO_LOG
	// Declares class to tag logged messages with.
	// See top of file for example of how to use this
	
typedef LLError::NoClassInfo _LL_CLASS_TO_LOG;
	// Outside a class declaration, or in class without LOG_CLASS(), this
	// typedef causes the messages to not be associated with any class.

/////////////////////////////////
// Error Logging Macros
// See top of file for common usage.
/////////////////////////////////

// Instead of using LL_DEBUGS(), LL_INFOS() et al., it may be tempting to
// directly code the lllog() macro so you can pass in the LLError::ELevel as a
// variable. DON'T DO IT! The reason is that the first time control passes
// through lllog(), it initializes a local static LLError::CallSite with that
// *first* ELevel value. All subsequent visits will decide whether or not to
// emit output based on the *first* ELevel value bound into that static
// CallSite instance. Use LL_VLOGS() instead. lllog() assumes its ELevel
// argument never varies.

// this macro uses a one-shot do statement to avoid parsing errors when
// writing control flow statements without braces:
// if (condition) LL_INFOS() << "True" << LL_ENDL; else LL_INFOS()() << "False" << LL_ENDL;

#define lllog(level, once, ...)                                         \
    do {                                                                \
        LL_PROFILE_ZONE_NAMED("lllog");                                 \
		const char* tags[] = {"", ##__VA_ARGS__};                       \
		static LLError::CallSite _site(lllog_site_args_(level, once, tags)); \
		lllog_test_()

#define lllog_test_()                           \
		if (LL_UNLIKELY(_site.shouldLog()))     \
		{                                       \
			std::ostringstream _out;            \
			_out

#define lllog_site_args_(level, once, tags)                 \
	level, __FILE__, __LINE__, typeid(_LL_CLASS_TO_LOG),    \
	__FUNCTION__, once, &tags[1], LL_ARRAY_SIZE(tags)-1

//Use this construct if you need to do computation in the middle of a
//message:
//	
//	LL_INFOS("AgentGesture") << "the agent " << agend_id;
//	switch (f)
//	{
//		case FOP_SHRUGS:	LL_CONT << "shrugs";				break;
//		case FOP_TAPS:		LL_CONT << "points at " << who;	break;
//		case FOP_SAYS:		LL_CONT << "says " << message;	break;
//	}
//	LL_CONT << " for " << t << " seconds" << LL_ENDL;
//	
//Such computation is done iff the message will be logged.
#define LL_CONT	_out

#define LL_NEWLINE '\n'

// Use this only in LL_ERRS or in a place that LL_ERRS may not be used
#define LLERROR_CRASH                                   \
{                                                       \
    crashdriver([](int* ptr){ *ptr = 0; exit(*ptr); }); \
}

#define LL_ENDL                                         \
            LLError::End();                             \
            LLError::Log::flush(_out, _site);           \
            if (_site.mLevel == LLError::LEVEL_ERROR)   \
            {                                           \
                LLERROR_CRASH                           \
            }                                           \
        }                                               \
    } while(0)

// NEW Macros for debugging, allow the passing of a string tag

// Pass comma separated list of tags (currently only supports up to 0, 1, or 2)
#define LL_DEBUGS(...)	lllog(LLError::LEVEL_DEBUG, false, ##__VA_ARGS__)
#define LL_INFOS(...)	lllog(LLError::LEVEL_INFO, false, ##__VA_ARGS__)
#define LL_WARNS(...)	lllog(LLError::LEVEL_WARN, false, ##__VA_ARGS__)
#define LL_ERRS(...)	lllog(LLError::LEVEL_ERROR, false, ##__VA_ARGS__)
// alternative to llassert_always that prints explanatory message
// note ## token paste operator hack used above will only work in gcc following
// a comma and is completely unnecessary in VS since the comma is automatically
// suppressed
// https://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html
// https://docs.microsoft.com/en-us/cpp/preprocessor/variadic-macros?view=vs-2015
#define LL_WARNS_IF(exp, ...)	if (exp) LL_WARNS(__VA_ARGS__) << "(" #exp ")"
#define LL_ERRS_IF(exp, ...)	if (exp) LL_ERRS(__VA_ARGS__) << "(" #exp ")"

// Only print the log message once (good for warnings or infos that would otherwise
// spam the log file over and over, such as tighter loops).
#define LL_DEBUGS_ONCE(...)	lllog(LLError::LEVEL_DEBUG, true, ##__VA_ARGS__)
#define LL_INFOS_ONCE(...)	lllog(LLError::LEVEL_INFO, true, ##__VA_ARGS__)
#define LL_WARNS_ONCE(...)	lllog(LLError::LEVEL_WARN, true, ##__VA_ARGS__)

// Use this if you need to pass LLError::ELevel as a variable.
#define LL_VLOGS(level, ...)      llvlog(level, false, ##__VA_ARGS__)
#define LL_VLOGS_ONCE(level, ...) llvlog(level, true,  ##__VA_ARGS__)

// The problem with using lllog() with a variable level is that the first time
// through, it initializes a static CallSite instance with whatever level you
// pass. That first level is bound into the CallSite; the level parameter is
// never again examined. One approach to variable level would be to
// dynamically construct a CallSite instance every call -- which could get
// expensive, depending on context. So instead, initialize a static CallSite
// for each level value we support, then dynamically select the CallSite
// instance for the passed level value.
// Compare implementation to lllog() above.
#define llvlog(level, once, ...)                                        \
	do {                                                                \
		const char* tags[] = {"", ##__VA_ARGS__};                       \
		/* Need a static CallSite instance per expected ELevel value. */ \
		/* Since we intend to index this array with the ELevel, */      \
		/* _sites[0] should be ELevel(0), and so on -- avoid using */   \
		/* ELevel symbolic names when initializing -- except for */     \
		/* the last entry, which handles anything beyond the end. */    \
		/* (Commented ELevel value names are from 2016-09-01.) */       \
		/* Passing an ELevel past the end of this array is itself */    \
		/* a fatal error, so ensure the last is LEVEL_ERROR. */         \
		static LLError::CallSite _sites[] =                             \
		{                                                               \
			/* LEVEL_DEBUG */                                           \
			LLError::CallSite(lllog_site_args_(LLError::ELevel(0), once, tags)), \
			/* LEVEL_INFO */                                            \
			LLError::CallSite(lllog_site_args_(LLError::ELevel(1), once, tags)), \
			/* LEVEL_WARN */                                            \
			LLError::CallSite(lllog_site_args_(LLError::ELevel(2), once, tags)), \
			/* LEVEL_ERROR */                                           \
			LLError::CallSite(lllog_site_args_(LLError::LEVEL_ERROR, once, tags)) \
		};                                                              \
		/* Clamp the passed 'level' to at most last entry */            \
		std::size_t which((std::size_t(level) >= LL_ARRAY_SIZE(_sites)) ? \
						  (LL_ARRAY_SIZE(_sites) - 1) : std::size_t(level)); \
		/* selected CallSite *must* be named _site for LL_ENDL */       \
		LLError::CallSite& _site(_sites[which]);                        \
		lllog_test_()

/*
// Check at run-time whether logging is enabled, without generating output.
Resist the temptation to add a function like this because it incurs the
expense of locking and map-searching every time control reaches it.
bool debugLoggingEnabled(const std::string& tag);

Instead of:

if debugLoggingEnabled("SomeTag")
{
    // ... presumably expensive operation ...
    LL_DEBUGS("SomeTag") << ... << LL_ENDL;
}

Use this:

LL_DEBUGS("SomeTag");
// ... presumably expensive operation ...
LL_CONT << ...;
LL_ENDL;

LL_DEBUGS("SomeTag") performs the locking and map-searching ONCE, then caches
the result in a static variable.
*/ 

// used by LLERROR_CRASH
void crashdriver(void (*)(int*));

#endif // LL_LLERROR_H