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