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