include/wx/log.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/log.h
   3 // Purpose:     Assorted wxLogXXX functions, and wxLog (sink for logs)
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     29/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // Licence:     wxWidgets licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_LOG_H_
  13 #define _WX_LOG_H_
  14
  15 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  16     #pragma interface "log.h"
  17 #endif
  18
  19 #include "wx/defs.h"
  20
  21 // ----------------------------------------------------------------------------
  22 // types
  23 // ----------------------------------------------------------------------------
  24
  25 // NB: these types are needed even if wxUSE_LOG == 0
  26 typedef unsigned long wxTraceMask;
  27 typedef unsigned long wxLogLevel;
  28
  29 // ----------------------------------------------------------------------------
  30 // headers
  31 // ----------------------------------------------------------------------------
  32
  33 #include "wx/string.h"
  34
  35 #if wxUSE_LOG
  36
  37 #include "wx/arrstr.h"
  38
  39 #ifndef __WXWINCE__
  40     #include <time.h>   // for time_t
  41 #endif
  42
  43 #include "wx/dynarray.h"
  44
  45 #ifndef wxUSE_LOG_DEBUG
  46 #  ifdef __WXDEBUG__
  47 #    define wxUSE_LOG_DEBUG 1
  48 #  else // !__WXDEBUG__
  49 #    define wxUSE_LOG_DEBUG 0
  50 #  endif
  51 #endif
  52
  53 // ----------------------------------------------------------------------------
  54 // forward declarations
  55 // ----------------------------------------------------------------------------
  56
  57 #if wxUSE_GUI
  58     class WXDLLIMPEXP_CORE wxTextCtrl;
  59     class WXDLLIMPEXP_CORE wxLogFrame;
  60     class WXDLLIMPEXP_CORE wxFrame;
  61 #endif // wxUSE_GUI
  62
  63 // ----------------------------------------------------------------------------
  64 // constants
  65 // ----------------------------------------------------------------------------
  66
  67 // different standard log levels (you may also define your own)
  68 enum
  69 {
  70     wxLOG_FatalError, // program can't continue, abort immediately
  71     wxLOG_Error,      // a serious error, user must be informed about it
  72     wxLOG_Warning,    // user is normally informed about it but may be ignored
  73     wxLOG_Message,    // normal message (i.e. normal output of a non GUI app)
  74     wxLOG_Status,     // informational: might go to the status line of GUI app
  75     wxLOG_Info,       // informational message (a.k.a. 'Verbose')
  76     wxLOG_Debug,      // never shown to the user, disabled in release mode
  77     wxLOG_Trace,      // trace messages are also only enabled in debug mode
  78     wxLOG_Progress,   // used for progress indicator (not yet)
  79     wxLOG_User = 100, // user defined levels start here
  80     wxLOG_Max = 10000
  81 };
  82
  83 // symbolic trace masks - wxLogTrace("foo", "some trace message...") will be
  84 // discarded unless the string "foo" has been added to the list of allowed
  85 // ones with AddTraceMask()
  86
  87 #define wxTRACE_MemAlloc wxT("memalloc") // trace memory allocation (new/delete)
  88 #define wxTRACE_Messages wxT("messages") // trace window messages/X callbacks
  89 #define wxTRACE_ResAlloc wxT("resalloc") // trace GDI resource allocation
  90 #define wxTRACE_RefCount wxT("refcount") // trace various ref counting operations
  91
  92 #ifdef  __WXMSW__
  93     #define wxTRACE_OleCalls wxT("ole")  // OLE interface calls
  94 #endif
  95
  96 // the trace masks have been superceded by symbolic trace constants, they're
  97 // for compatibility only andwill be removed soon - do NOT use them
  98
  99 // meaning of different bits of the trace mask (which allows selectively
 100 // enable/disable some trace messages)
 101 #define wxTraceMemAlloc 0x0001  // trace memory allocation (new/delete)
 102 #define wxTraceMessages 0x0002  // trace window messages/X callbacks
 103 #define wxTraceResAlloc 0x0004  // trace GDI resource allocation
 104 #define wxTraceRefCount 0x0008  // trace various ref counting operations
 105
 106 #ifdef  __WXMSW__
 107     #define wxTraceOleCalls 0x0100  // OLE interface calls
 108 #endif
 109
 110 #include "wx/iosfwrap.h"
 111
 112 // ----------------------------------------------------------------------------
 113 // derive from this class to redirect (or suppress, or ...) log messages
 114 // normally, only a single instance of this class exists but it's not enforced
 115 // ----------------------------------------------------------------------------
 116
 117 class WXDLLIMPEXP_BASE wxLog
 118 {
 119 public:
 120     // ctor
 121     wxLog();
 122
 123     // Internal buffer.
 124
 125     // Allow replacement of the fixed size static buffer with
 126     // a user allocated one.  Pass in NULL to restore the
 127     // built in static buffer.
 128     static wxChar *SetLogBuffer( wxChar *buf, size_t size = 0 );
 129
 130     // these functions allow to completely disable all log messages
 131
 132     // is logging disabled now?
 133     static bool IsEnabled() { return ms_doLog; }
 134
 135     // change the flag state, return the previous one
 136     static bool EnableLogging(bool doIt = true)
 137     { bool doLogOld = ms_doLog; ms_doLog = doIt; return doLogOld; }
 138
 139     // static sink function - see DoLog() for function to overload in the
 140     // derived classes
 141     static void OnLog(wxLogLevel level, const wxChar *szString, time_t t)
 142     {
 143         if ( IsEnabled() && ms_logLevel >= level )
 144         {
 145             wxLog *pLogger = GetActiveTarget();
 146             if ( pLogger )
 147                 pLogger->DoLog(level, szString, t);
 148         }
 149     }
 150
 151     // message buffering
 152
 153     // flush shows all messages if they're not logged immediately (FILE
 154     // and iostream logs don't need it, but wxGuiLog does to avoid showing
 155     // 17 modal dialogs one after another)
 156     virtual void Flush();
 157
 158     // flush the active target if any
 159     static void FlushActive()
 160     {
 161         if ( !ms_suspendCount )
 162         {
 163             wxLog *log = GetActiveTarget();
 164             if ( log )
 165                 log->Flush();
 166         }
 167     }
 168
 169     // only one sink is active at each moment
 170     // get current log target, will call wxApp::CreateLogTarget() to
 171     // create one if none exists
 172     static wxLog *GetActiveTarget();
 173
 174     // change log target, pLogger may be NULL
 175     static wxLog *SetActiveTarget(wxLog *pLogger);
 176
 177     // suspend the message flushing of the main target until the next call
 178     // to Resume() - this is mainly for internal use (to prevent wxYield()
 179     // from flashing the messages)
 180     static void Suspend() { ms_suspendCount++; }
 181
 182     // must be called for each Suspend()!
 183     static void Resume() { ms_suspendCount--; }
 184
 185     // functions controlling the default wxLog behaviour
 186     // verbose mode is activated by standard command-line '-verbose'
 187     // option
 188     static void SetVerbose(bool bVerbose = true) { ms_bVerbose = bVerbose; }
 189
 190     // Set log level.  Log messages with level > logLevel will not be logged.
 191     static void SetLogLevel(wxLogLevel logLevel) { ms_logLevel = logLevel; }
 192
 193     // should GetActiveTarget() try to create a new log object if the
 194     // current is NULL?
 195     static void DontCreateOnDemand();
 196
 197     // trace mask (see wxTraceXXX constants for details)
 198     static void SetTraceMask(wxTraceMask ulMask) { ms_ulTraceMask = ulMask; }
 199
 200     // add string trace mask
 201     static void AddTraceMask(const wxString& str)
 202     { ms_aTraceMasks.push_back(str); }
 203
 204     // add string trace mask
 205     static void RemoveTraceMask(const wxString& str);
 206
 207     // remove all string trace masks
 208     static void ClearTraceMasks();
 209
 210     // get string trace masks
 211     static const wxArrayString &GetTraceMasks() { return ms_aTraceMasks; }
 212
 213     // sets the timestamp string: this is used as strftime() format string
 214     // for the log targets which add time stamps to the messages - set it
 215     // to NULL to disable time stamping completely.
 216     static void SetTimestamp(const wxChar *ts) { ms_timestamp = ts; }
 217
 218
 219     // accessors
 220
 221     // gets the verbose status
 222     static bool GetVerbose() { return ms_bVerbose; }
 223
 224     // get trace mask
 225     static wxTraceMask GetTraceMask() { return ms_ulTraceMask; }
 226
 227     // is this trace mask in the list?
 228     static bool IsAllowedTraceMask(const wxChar *mask);
 229
 230     // return the current loglevel limit
 231     static wxLogLevel GetLogLevel() { return ms_logLevel; }
 232
 233     // get the current timestamp format string (may be NULL)
 234     static const wxChar *GetTimestamp() { return ms_timestamp; }
 235
 236
 237     // helpers
 238
 239     // put the time stamp into the string if ms_timestamp != NULL (don't
 240     // change it otherwise)
 241     static void TimeStamp(wxString *str);
 242
 243     // make dtor virtual for all derived classes
 244     virtual ~wxLog() { }
 245
 246
 247     // this method exists for backwards compatibility only, don't use
 248     bool HasPendingMessages() const { return true; }
 249
 250 protected:
 251     // the logging functions that can be overriden
 252
 253     // default DoLog() prepends the time stamp and a prefix corresponding
 254     // to the message to szString and then passes it to DoLogString()
 255     virtual void DoLog(wxLogLevel level, const wxChar *szString, time_t t);
 256
 257     // default DoLogString does nothing but is not pure virtual because if
 258     // you override DoLog() you might not need it at all
 259     virtual void DoLogString(const wxChar *szString, time_t t);
 260
 261 private:
 262     // static variables
 263     // ----------------
 264
 265     static wxLog      *ms_pLogger;      // currently active log sink
 266     static bool        ms_doLog;        // false => all logging disabled
 267     static bool        ms_bAutoCreate;  // create new log targets on demand?
 268     static bool        ms_bVerbose;     // false => ignore LogInfo messages
 269
 270     static wxLogLevel  ms_logLevel;     // limit logging to levels <= ms_logLevel
 271
 272     static size_t      ms_suspendCount; // if positive, logs are not flushed
 273
 274     // format string for strftime(), if NULL, time stamping log messages is
 275     // disabled
 276     static const wxChar *ms_timestamp;
 277
 278     static wxTraceMask ms_ulTraceMask;   // controls wxLogTrace behaviour
 279     static wxArrayString ms_aTraceMasks; // more powerful filter for wxLogTrace
 280 };
 281
 282 // ----------------------------------------------------------------------------
 283 // "trivial" derivations of wxLog
 284 // ----------------------------------------------------------------------------
 285
 286 // log everything to a "FILE *", stderr by default
 287 class WXDLLIMPEXP_BASE wxLogStderr : public wxLog
 288 {
 289     DECLARE_NO_COPY_CLASS(wxLogStderr)
 290
 291 public:
 292     // redirect log output to a FILE
 293     wxLogStderr(FILE *fp = (FILE *) NULL);
 294
 295 protected:
 296     // implement sink function
 297     virtual void DoLogString(const wxChar *szString, time_t t);
 298
 299     FILE *m_fp;
 300 };
 301
 302 #if wxUSE_STD_IOSTREAM
 303
 304 // log everything to an "ostream", cerr by default
 305 class WXDLLIMPEXP_BASE wxLogStream : public wxLog
 306 {
 307 public:
 308     // redirect log output to an ostream
 309     wxLogStream(wxSTD ostream *ostr = (wxSTD ostream *) NULL);
 310
 311 protected:
 312     // implement sink function
 313     virtual void DoLogString(const wxChar *szString, time_t t);
 314
 315     // using ptr here to avoid including <iostream.h> from this file
 316     wxSTD ostream *m_ostr;
 317 };
 318
 319 #endif // wxUSE_STD_IOSTREAM
 320
 321 // ----------------------------------------------------------------------------
 322 // /dev/null log target: suppress logging until this object goes out of scope
 323 // ----------------------------------------------------------------------------
 324
 325 // example of usage:
 326 /*
 327     void Foo()
 328     {
 329         wxFile file;
 330
 331         // wxFile.Open() normally complains if file can't be opened, we don't
 332         // want it
 333         wxLogNull logNo;
 334
 335         if ( !file.Open("bar") )
 336             ... process error ourselves ...
 337
 338         // ~wxLogNull called, old log sink restored
 339     }
 340  */
 341 class WXDLLIMPEXP_BASE wxLogNull
 342 {
 343 public:
 344     wxLogNull() : m_flagOld(wxLog::EnableLogging(false)) { }
 345     ~wxLogNull() { (void)wxLog::EnableLogging(m_flagOld); }
 346
 347 private:
 348     bool m_flagOld; // the previous value of the wxLog::ms_doLog
 349 };
 350
 351 // ----------------------------------------------------------------------------
 352 // chaining log target: installs itself as a log target and passes all
 353 // messages to the real log target given to it in the ctor but also forwards
 354 // them to the previously active one
 355 //
 356 // note that you don't have to call SetActiveTarget() with this class, it
 357 // does it itself in its ctor
 358 // ----------------------------------------------------------------------------
 359
 360 class WXDLLIMPEXP_BASE wxLogChain : public wxLog
 361 {
 362 public:
 363     wxLogChain(wxLog *logger);
 364     virtual ~wxLogChain();
 365
 366     // change the new log target
 367     void SetLog(wxLog *logger);
 368
 369     // this can be used to temporarily disable (and then reenable) passing
 370     // messages to the old logger (by default we do pass them)
 371     void PassMessages(bool bDoPass) { m_bPassMessages = bDoPass; }
 372
 373     // are we passing the messages to the previous log target?
 374     bool IsPassingMessages() const { return m_bPassMessages; }
 375
 376     // return the previous log target (may be NULL)
 377     wxLog *GetOldLog() const { return m_logOld; }
 378
 379     // override base class version to flush the old logger as well
 380     virtual void Flush();
 381
 382 protected:
 383     // pass the chain to the old logger if needed
 384     virtual void DoLog(wxLogLevel level, const wxChar *szString, time_t t);
 385
 386 private:
 387     // the current log target
 388     wxLog *m_logNew;
 389
 390     // the previous log target
 391     wxLog *m_logOld;
 392
 393     // do we pass the messages to the old logger?
 394     bool m_bPassMessages;
 395
 396     DECLARE_NO_COPY_CLASS(wxLogChain)
 397 };
 398
 399 // a chain log target which uses itself as the new logger
 400 class WXDLLIMPEXP_BASE wxLogPassThrough : public wxLogChain
 401 {
 402 public:
 403     wxLogPassThrough();
 404
 405 private:
 406     DECLARE_NO_COPY_CLASS(wxLogPassThrough)
 407 };
 408
 409 #if wxUSE_GUI
 410     // include GUI log targets:
 411     #include "wx/generic/logg.h"
 412 #endif // wxUSE_GUI
 413
 414 // ============================================================================
 415 // global functions
 416 // ============================================================================
 417
 418 // ----------------------------------------------------------------------------
 419 // Log functions should be used by application instead of stdio, iostream &c
 420 // for log messages for easy redirection
 421 // ----------------------------------------------------------------------------
 422
 423 // ----------------------------------------------------------------------------
 424 // get error code/error message from system in a portable way
 425 // ----------------------------------------------------------------------------
 426
 427 // return the last system error code
 428 WXDLLIMPEXP_BASE unsigned long wxSysErrorCode();
 429
 430 // return the error message for given (or last if 0) error code
 431 WXDLLIMPEXP_BASE const wxChar* wxSysErrorMsg(unsigned long nErrCode = 0);
 432
 433 // ----------------------------------------------------------------------------
 434 // define wxLog<level>
 435 // ----------------------------------------------------------------------------
 436
 437 #define DECLARE_LOG_FUNCTION(level)                                         \
 438 extern void WXDLLIMPEXP_BASE wxVLog##level(const wxChar *szFormat,          \
 439                                       va_list argptr);                      \
 440 extern void WXDLLIMPEXP_BASE wxLog##level(const wxChar *szFormat,           \
 441                                      ...) ATTRIBUTE_PRINTF_1
 442 #define DECLARE_LOG_FUNCTION2_EXP(level, arg, expdecl)                      \
 443 extern void expdecl wxVLog##level(arg, const wxChar *szFormat,              \
 444                                       va_list argptr);                      \
 445 extern void expdecl wxLog##level(arg, const wxChar *szFormat,               \
 446                                      ...) ATTRIBUTE_PRINTF_2
 447 #define DECLARE_LOG_FUNCTION2(level, arg)                                   \
 448     DECLARE_LOG_FUNCTION2_EXP(level, arg, WXDLLIMPEXP_BASE)
 449
 450 #else // !wxUSE_LOG
 451
 452 // log functions do nothing at all
 453 #define DECLARE_LOG_FUNCTION(level)                                         \
 454 inline void wxVLog##level(const wxChar *szFormat,                           \
 455                                      va_list argptr) { }                    \
 456 inline void wxLog##level(const wxChar *szFormat, ...) { }
 457 #define DECLARE_LOG_FUNCTION2(level, arg)                                   \
 458 inline void wxVLog##level(arg, const wxChar *szFormat,                      \
 459                                      va_list argptr) {}                     \
 460 inline void wxLog##level(arg, const wxChar *szFormat, ...) { }
 461
 462 // Empty Class to fake wxLogNull
 463 class WXDLLIMPEXP_BASE wxLogNull
 464 {
 465 public:
 466     wxLogNull() { }
 467 };
 468
 469 // Dummy macros to replace some functions.
 470 #define wxSysErrorCode() (unsigned long)0
 471 #define wxSysErrorMsg( X ) (const wxChar*)NULL
 472
 473 // Fake symbolic trace masks... for those that are used frequently
 474 #define wxTRACE_OleCalls wxEmptyString // OLE interface calls
 475
 476 #endif // wxUSE_LOG/!wxUSE_LOG
 477
 478 // a generic function for all levels (level is passes as parameter)
 479 DECLARE_LOG_FUNCTION2(Generic, wxLogLevel level);
 480
 481 // one function per each level
 482 DECLARE_LOG_FUNCTION(FatalError);
 483 DECLARE_LOG_FUNCTION(Error);
 484 DECLARE_LOG_FUNCTION(Warning);
 485 DECLARE_LOG_FUNCTION(Message);
 486 DECLARE_LOG_FUNCTION(Info);
 487 DECLARE_LOG_FUNCTION(Verbose);
 488
 489 // this function sends the log message to the status line of the top level
 490 // application frame, if any
 491 DECLARE_LOG_FUNCTION(Status);
 492
 493 #if wxUSE_GUI
 494     // this one is the same as previous except that it allows to explicitly
 495     // specify the frame to which the output should go
 496     DECLARE_LOG_FUNCTION2_EXP(Status, wxFrame *pFrame, WXDLLIMPEXP_CORE);
 497 #endif // wxUSE_GUI
 498
 499 // additional one: as wxLogError, but also logs last system call error code
 500 // and the corresponding error message if available
 501 DECLARE_LOG_FUNCTION(SysError);
 502
 503 // and another one which also takes the error code (for those broken APIs
 504 // that don't set the errno (like registry APIs in Win32))
 505 DECLARE_LOG_FUNCTION2(SysError, long lErrCode);
 506
 507 // debug functions do nothing in release mode
 508 #if wxUSE_LOG_DEBUG
 509     DECLARE_LOG_FUNCTION(Debug);
 510
 511     // there is no more unconditional LogTrace: it is not different from
 512     // LogDebug and it creates overload ambiguities
 513     //DECLARE_LOG_FUNCTION(Trace);
 514
 515     // this version only logs the message if the mask had been added to the
 516     // list of masks with AddTraceMask()
 517     DECLARE_LOG_FUNCTION2(Trace, const wxChar *mask);
 518
 519     // and this one does nothing if all of level bits are not set in
 520     // wxLog::GetActive()->GetTraceMask() -- it's deprecated in favour of
 521     // string identifiers
 522     DECLARE_LOG_FUNCTION2(Trace, wxTraceMask mask);
 523 #else   //!debug
 524     // these functions do nothing in release builds
 525     inline void wxVLogDebug(const wxChar *, va_list) { }
 526     inline void wxLogDebug(const wxChar *, ...) { }
 527     inline void wxVLogTrace(wxTraceMask, const wxChar *, va_list) { }
 528     inline void wxLogTrace(wxTraceMask, const wxChar *, ...) { }
 529     inline void wxVLogTrace(const wxChar *, const wxChar *, va_list) { }
 530     inline void wxLogTrace(const wxChar *, const wxChar *, ...) { }
 531 #endif // debug/!debug
 532
 533 // wxLogFatalError helper: show the (fatal) error to the user in a safe way,
 534 // i.e. without using wxMessageBox() for example because it could crash
 535 void WXDLLIMPEXP_BASE
 536 wxSafeShowMessage(const wxString& title, const wxString& text);
 537
 538 // ----------------------------------------------------------------------------
 539 // debug only logging functions: use them with API name and error code
 540 // ----------------------------------------------------------------------------
 541
 542 #ifdef __WXDEBUG__
 543     // make life easier for people using VC++ IDE: clicking on the message
 544     // will take us immediately to the place of the failed API
 545 #ifdef __VISUALC__
 546     #define wxLogApiError(api, rc)                                            \
 547         wxLogDebug(wxT("%s(%d): '%s' failed with error 0x%08lx (%s)."),       \
 548                    __TFILE__, __LINE__, api,                                  \
 549                    (long)rc, wxSysErrorMsg(rc))
 550 #else // !VC++
 551     #define wxLogApiError(api, rc)                                            \
 552         wxLogDebug(wxT("In file %s at line %d: '%s' failed with ")            \
 553                    wxT("error 0x%08lx (%s)."),                                \
 554                    __TFILE__, __LINE__, api,                                  \
 555                    (long)rc, wxSysErrorMsg(rc))
 556 #endif // VC++/!VC++
 557
 558     #define wxLogLastError(api) wxLogApiError(api, wxSysErrorCode())
 559
 560 #else   //!debug
 561     inline void wxLogApiError(const wxChar *, long) { }
 562     inline void wxLogLastError(const wxChar *) { }
 563 #endif  //debug/!debug
 564
 565 // wxCocoa has additiional trace masks
 566 #if defined(__WXCOCOA__)
 567 #include "wx/cocoa/log.h"
 568 #endif
 569
 570 #endif  // _WX_LOG_H_
 571