include/wx/fswatcher.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/fswatcher.h
   3 // Purpose:     wxFileSystemWatcherBase
   4 // Author:      Bartosz Bekier
   5 // Created:     2009-05-23
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2009 Bartosz Bekier <bartosz.bekier@gmail.com>
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_FSWATCHER_BASE_H_
  12 #define _WX_FSWATCHER_BASE_H_
  13
  14 #include "wx/defs.h"
  15
  16 #if wxUSE_FSWATCHER
  17
  18 #include "wx/log.h"
  19 #include "wx/event.h"
  20 #include "wx/evtloop.h"
  21 #include "wx/filename.h"
  22 #include "wx/dir.h"
  23 #include "wx/hashmap.h"
  24
  25 #define wxTRACE_FSWATCHER "fswatcher"
  26
  27 // ----------------------------------------------------------------------------
  28 // wxFileSystemWatcherEventType & wxFileSystemWatcherEvent
  29 // ----------------------------------------------------------------------------
  30
  31 /**
  32  * Possible types of file system events.
  33  * This is a subset that will work fine an all platforms (actually, we will
  34  * see how it works on Mac).
  35  *
  36  * We got 2 types of error events:
  37  * - warning: these are not fatal and further events can still be generated
  38  * - error: indicates fatal error and causes that no more events will happen
  39  */
  40 enum
  41 {
  42     wxFSW_EVENT_CREATE = 0x01,
  43     wxFSW_EVENT_DELETE = 0x02,
  44     wxFSW_EVENT_RENAME = 0x04,
  45     wxFSW_EVENT_MODIFY = 0x08,
  46     wxFSW_EVENT_ACCESS = 0x10,
  47     wxFSW_EVENT_ATTRIB = 0x20, // Currently this is wxGTK-only
  48
  49     // error events
  50     wxFSW_EVENT_WARNING = 0x40,
  51     wxFSW_EVENT_ERROR = 0x80,
  52     wxFSW_EVENT_ALL = wxFSW_EVENT_CREATE | wxFSW_EVENT_DELETE |
  53                          wxFSW_EVENT_RENAME | wxFSW_EVENT_MODIFY |
  54                          wxFSW_EVENT_ACCESS | wxFSW_EVENT_ATTRIB |
  55                          wxFSW_EVENT_WARNING | wxFSW_EVENT_ERROR
  56 #ifdef wxHAS_INOTIFY
  57     ,wxFSW_EVENT_UNMOUNT = 0x2000
  58 #endif
  59 };
  60
  61 // Type of the path watched, used only internally for now.
  62 enum wxFSWPathType
  63 {
  64     wxFSWPath_None,     // Invalid value for an initialized watch.
  65     wxFSWPath_File,     // Plain file.
  66     wxFSWPath_Dir,      // Watch a directory and the files in it.
  67     wxFSWPath_Tree      // Watch a directory and all its children recursively.
  68 };
  69
  70
  71 /**
  72  * Event containing information about file system change.
  73  */
  74 class WXDLLIMPEXP_FWD_BASE wxFileSystemWatcherEvent;
  75 wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_BASE, wxEVT_FSWATCHER,
  76                          wxFileSystemWatcherEvent);
  77
  78 class WXDLLIMPEXP_BASE wxFileSystemWatcherEvent: public wxEvent
  79 {
  80 public:
  81     wxFileSystemWatcherEvent(int changeType, int watchid = wxID_ANY) :
  82         wxEvent(watchid, wxEVT_FSWATCHER),
  83         m_changeType(changeType)
  84     {
  85     }
  86
  87     wxFileSystemWatcherEvent(int changeType, const wxString& errorMsg,
  88                              int watchid = wxID_ANY) :
  89         wxEvent(watchid, wxEVT_FSWATCHER),
  90         m_changeType(changeType), m_errorMsg(errorMsg)
  91     {
  92     }
  93
  94     wxFileSystemWatcherEvent(int changeType,
  95                              const wxFileName& path, const wxFileName& newPath,
  96                              int watchid = wxID_ANY) :
  97          wxEvent(watchid, wxEVT_FSWATCHER),
  98          m_changeType(changeType), m_path(path), m_newPath(newPath)
  99     {
 100     }
 101
 102     /**
 103      * Returns the path at which the event occurred.
 104      */
 105     const wxFileName& GetPath() const
 106     {
 107         return m_path;
 108     }
 109
 110     /**
 111      * Sets the path at which the event occurred
 112      */
 113     void SetPath(const wxFileName& path)
 114     {
 115         m_path = path;
 116     }
 117
 118     /**
 119      * In case of rename(move?) events, returns the new path related to the
 120      * event. The "new" means newer in the sense of time. In case of other
 121      * events it returns the same path as GetPath().
 122      */
 123     const wxFileName& GetNewPath() const
 124     {
 125         return m_newPath;
 126     }
 127
 128     /**
 129      * Sets the new path related to the event. See above.
 130      */
 131     void SetNewPath(const wxFileName& path)
 132     {
 133         m_newPath = path;
 134     }
 135
 136     /**
 137      * Returns the type of file system event that occurred.
 138      */
 139     int GetChangeType() const
 140     {
 141         return m_changeType;
 142     }
 143
 144     virtual wxEvent* Clone() const
 145     {
 146         wxFileSystemWatcherEvent* evt = new wxFileSystemWatcherEvent(*this);
 147         evt->m_errorMsg = m_errorMsg.Clone();
 148         evt->m_path = wxFileName(m_path.GetFullPath().Clone());
 149         evt->m_newPath = wxFileName(m_newPath.GetFullPath().Clone());
 150         return evt;
 151     }
 152
 153     virtual wxEventCategory GetEventCategory() const
 154     {
 155         // TODO this has to be merged with "similar" categories and changed
 156         return wxEVT_CATEGORY_UNKNOWN;
 157     }
 158
 159     /**
 160      * Returns if this error is an error event
 161      */
 162     bool IsError() const
 163     {
 164         return (m_changeType & (wxFSW_EVENT_ERROR | wxFSW_EVENT_WARNING)) != 0;
 165     }
 166
 167     wxString GetErrorDescription() const
 168     {
 169         return m_errorMsg;
 170     }
 171
 172     /**
 173      * Returns a wxString describing an event useful for debugging or testing
 174      */
 175     wxString ToString() const;
 176
 177 protected:
 178     int m_changeType;
 179     wxFileName m_path;
 180     wxFileName m_newPath;
 181     wxString m_errorMsg;
 182 };
 183
 184 typedef void (wxEvtHandler::*wxFileSystemWatcherEventFunction)
 185                                                 (wxFileSystemWatcherEvent&);
 186
 187 #define wxFileSystemWatcherEventHandler(func) \
 188     wxEVENT_HANDLER_CAST(wxFileSystemWatcherEventFunction, func)
 189
 190 #define EVT_FSWATCHER(winid, func) \
 191     wx__DECLARE_EVT1(wxEVT_FSWATCHER, winid, wxFileSystemWatcherEventHandler(func))
 192
 193 // ----------------------------------------------------------------------------
 194 // wxFileSystemWatcherBase: interface for wxFileSystemWatcher
 195 // ----------------------------------------------------------------------------
 196
 197 // Simple container to store information about one watched path.
 198 class wxFSWatchInfo
 199 {
 200 public:
 201     wxFSWatchInfo() :
 202         m_events(-1), m_type(wxFSWPath_None), m_refcount(-1)
 203     {
 204     }
 205
 206     wxFSWatchInfo(const wxString& path,
 207                   int events,
 208                   wxFSWPathType type,
 209                   const wxString& filespec = wxString()) :
 210         m_path(path), m_filespec(filespec), m_events(events), m_type(type),
 211         m_refcount(1)
 212     {
 213     }
 214
 215     const wxString& GetPath() const
 216     {
 217         return m_path;
 218     }
 219
 220     const wxString& GetFilespec() const { return m_filespec; }
 221
 222     int GetFlags() const
 223     {
 224         return m_events;
 225     }
 226
 227     wxFSWPathType GetType() const
 228     {
 229         return m_type;
 230     }
 231
 232     // Reference counting of watch entries is used to avoid watching the same
 233     // file system path multiple times (this can happen even accidentally, e.g.
 234     // when you have a recursive watch and then decide to watch some file or
 235     // directory under it separately).
 236     int IncRef()
 237     {
 238         return ++m_refcount;
 239     }
 240
 241     int DecRef()
 242     {
 243         wxASSERT_MSG( m_refcount > 0, wxS("Trying to decrement a zero count") );
 244         return --m_refcount;
 245     }
 246
 247 protected:
 248     wxString m_path;
 249     wxString m_filespec;      // For tree watches, holds any filespec to apply
 250     int m_events;
 251     wxFSWPathType m_type;
 252     int m_refcount;
 253 };
 254
 255 WX_DECLARE_STRING_HASH_MAP(wxFSWatchInfo, wxFSWatchInfoMap);
 256
 257 /**
 258  * Encapsulation of platform-specific file system event mechanism
 259  */
 260 class wxFSWatcherImpl;
 261
 262 /**
 263  * Main entry point for clients interested in file system events.
 264  * Defines interface that can be used to receive that kind of events.
 265  */
 266 class WXDLLIMPEXP_BASE wxFileSystemWatcherBase: public wxEvtHandler
 267 {
 268 public:
 269     wxFileSystemWatcherBase();
 270
 271     virtual ~wxFileSystemWatcherBase();
 272
 273     /**
 274      * Adds path to currently watched files. Any events concerning this
 275      * particular path will be sent to handler. Optionally a filter can be
 276      * specified to receive only events of particular type.
 277      *
 278      * Please note that when adding a dir, immediate children will be watched
 279      * as well.
 280      */
 281     virtual bool Add(const wxFileName& path, int events = wxFSW_EVENT_ALL);
 282
 283     /**
 284      * Like above, but recursively adds every file/dir in the tree rooted in
 285      * path. Additionally a file mask can be specified to include only files
 286      * of particular type.
 287      */
 288     virtual bool AddTree(const wxFileName& path, int events = wxFSW_EVENT_ALL,
 289                          const wxString& filespec = wxEmptyString);
 290
 291     /**
 292      * Removes path from the list of watched paths.
 293      */
 294     virtual bool Remove(const wxFileName& path);
 295
 296     /**
 297      * Same as above, but also removes every file belonging to the tree rooted
 298      * at path.
 299      */
 300     virtual bool RemoveTree(const wxFileName& path);
 301
 302     /**
 303      * Clears the list of currently watched paths.
 304      */
 305     virtual bool RemoveAll();
 306
 307     /**
 308      * Returns the number of watched paths
 309      */
 310     int GetWatchedPathsCount() const;
 311
 312     /**
 313      * Retrevies all watched paths and places them in wxArrayString. Returns
 314      * the number of paths.
 315      *
 316      * TODO think about API here: we need to return more information (like is
 317      * the path watched recursively)
 318      */
 319     int GetWatchedPaths(wxArrayString* paths) const;
 320
 321     wxEvtHandler* GetOwner() const
 322     {
 323         return m_owner;
 324     }
 325
 326     void SetOwner(wxEvtHandler* handler)
 327     {
 328         if (!handler)
 329             m_owner = this;
 330         else
 331             m_owner = handler;
 332     }
 333
 334
 335     // This is a semi-private function used by wxWidgets itself only.
 336     //
 337     // Delegates the real work of adding the path to wxFSWatcherImpl::Add() and
 338     // updates m_watches if the new path was successfully added.
 339     bool AddAny(const wxFileName& path, int events, wxFSWPathType type,
 340                 const wxString& filespec = wxString());
 341
 342 protected:
 343
 344     static wxString GetCanonicalPath(const wxFileName& path)
 345     {
 346         wxFileName path_copy = wxFileName(path);
 347         if ( !path_copy.Normalize() )
 348         {
 349             wxFAIL_MSG(wxString::Format("Unable to normalize path '%s'",
 350                                          path.GetFullPath()));
 351             return wxEmptyString;
 352         }
 353
 354         return path_copy.GetFullPath();
 355     }
 356
 357
 358     wxFSWatchInfoMap m_watches;        // path=>wxFSWatchInfo map
 359     wxFSWatcherImpl* m_service;     // file system events service
 360     wxEvtHandler* m_owner;             // handler for file system events
 361
 362     friend class wxFSWatcherImpl;
 363 };
 364
 365 // include the platform specific file defining wxFileSystemWatcher
 366 // inheriting from wxFileSystemWatcherBase
 367
 368 #ifdef wxHAS_INOTIFY
 369     #include "wx/unix/fswatcher_inotify.h"
 370     #define wxFileSystemWatcher wxInotifyFileSystemWatcher
 371 #elif defined(wxHAS_KQUEUE)
 372     #include "wx/unix/fswatcher_kqueue.h"
 373     #define wxFileSystemWatcher wxKqueueFileSystemWatcher
 374 #elif defined(__WINDOWS__)
 375     #include "wx/msw/fswatcher.h"
 376     #define wxFileSystemWatcher wxMSWFileSystemWatcher
 377 #else
 378     #include "wx/generic/fswatcher.h"
 379     #define wxFileSystemWatcher wxPollingFileSystemWatcher
 380 #endif
 381
 382 #endif // wxUSE_FSWATCHER
 383
 384 #endif /* _WX_FSWATCHER_BASE_H_ */