interface/wx/stackwalk.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        stackwalk.h
   3 // Purpose:     interface of wxStackWalker
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxStackWalker
  11
  12     wxStackWalker allows an application to enumerate, or walk, the stack frames
  13     (the function callstack).
  14
  15     It is mostly useful in only two situations: inside wxApp::OnFatalException
  16     function to programmatically get the location of the crash and, in debug builds,
  17     in wxApp::OnAssertFailure to report the caller of the failed assert.
  18
  19     wxStackWalker works by repeatedly calling the wxStackWalker::OnStackFrame
  20     method for each frame in the stack, so to use it you must derive your own
  21     class from it and override this method.
  22
  23     This class will not return anything except raw stack frame addresses if the
  24     debug information is not available. Under Win32 this means that the PDB file
  25     matching the program being executed should be present.
  26     Note that if you use Microsoft Visual C++ compiler, you can create PDB files
  27     even for the programs built in release mode and it doesn't affect the program
  28     size (at least if you don't forget to add @c /opt:ref option which is suppressed
  29     by using @c /debug linker option by default but should be always enabled for
  30     release builds).
  31     Under Unix, you need to compile your program with debugging information
  32     (usually using @c -g compiler and linker options) to get the file and line
  33     numbers information, however function names should be available even without it.
  34     Of course, all this is only @true if you build using a recent enough version
  35     of GNU libc which provides the @c backtrace() function needed to walk the stack.
  36
  37     See @ref overview_debugging for how to make it available.
  38
  39     @library{wxbase}
  40     @category{debugging}
  41
  42     @see wxStackFrame
  43 */
  44 class wxStackWalker
  45 {
  46 public:
  47     /**
  48         Constructor does nothing, use Walk() to walk the stack.
  49     */
  50     wxStackWalker();
  51
  52     /**
  53         Destructor does nothing neither but should be virtual as this class is used as
  54         a base one.
  55     */
  56     virtual ~wxStackWalker();
  57
  58     /**
  59         This function must be overrided to process the given frame.
  60     */
  61     void OnStackFrame(const wxStackFrame& frame);
  62
  63     /**
  64         Enumerate stack frames from the current location, skipping the initial
  65         number of them (this can be useful when Walk() is called from some known
  66         location and you don't want to see the first few frames anyhow; also
  67         notice that Walk() frame itself is not included if skip = 1).
  68
  69         Up to @a maxDepth frames are walked from the innermost to the outermost one.
  70     */
  71     virtual void Walk(size_t skip = 1, size_t maxDepth = 200);
  72
  73     /**
  74         Enumerate stack frames from the location of uncaught exception.
  75         This method can only be called from wxApp::OnFatalException().
  76
  77         Up to @a maxDepth frames are walked from the innermost to the outermost one.
  78     */
  79     virtual void WalkFromException(size_t maxDepth = 200);
  80 };
  81
  82
  83
  84 /**
  85     @class wxStackFrame
  86
  87     wxStackFrame represents a single stack frame, or a single function in the call
  88     stack, and is used exclusively together with wxStackWalker, see there for a more
  89     detailed discussion.
  90
  91     @library{wxbase}
  92     @category{debugging}
  93
  94     @see wxStackWalker
  95 */
  96 class wxStackFrame
  97 {
  98 public:
  99     /**
 100         Return the address of this frame.
 101     */
 102     void* GetAddress() const;
 103
 104     /**
 105         Return the name of the file containing this frame, empty if unavailable
 106         (typically because debug info is missing).
 107
 108         Use HasSourceLocation() to check whether the file name is available.
 109     */
 110     wxString GetFileName() const;
 111
 112     /**
 113         Get the level of this frame (deepest/innermost one is 0).
 114     */
 115     size_t GetLevel() const;
 116
 117     /**
 118         Return the line number of this frame, 0 if unavailable.
 119
 120         @see GetFileName()
 121     */
 122     size_t GetLine() const;
 123
 124     /**
 125         Get the module this function belongs to (empty if not available).
 126     */
 127     wxString GetModule() const;
 128
 129     /**
 130         Return the unmangled (if possible) name of the function containing this frame.
 131     */
 132     wxString GetName() const;
 133
 134     /**
 135         Return the return address of this frame.
 136     */
 137     size_t GetOffset() const;
 138
 139     /**
 140         Get the name, type and value (in text form) of the given parameter.
 141         Any pointer may be @NULL if you're not interested in the corresponding value.
 142
 143         Return @true if at least some values could be retrieved.
 144         This function currently is only implemented under Win32 and requires a PDB file.
 145     */
 146     bool GetParam(size_t n, wxString* type, wxString* name,
 147                   wxString* value) const;
 148
 149     /**
 150         Return the number of parameters of this function (may return 0 if we
 151         can't retrieve the parameters info even although the function does have
 152         parameters).
 153     */
 154     virtual size_t GetParamCount() const;
 155
 156     /**
 157         Return @true if we have the file name and line number for this frame.
 158     */
 159     bool HasSourceLocation() const;
 160 };
 161