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