src/common/fswatchercmn.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/fswatchercmn.cpp
   3 // Purpose:     wxMswFileSystemWatcher
   4 // Author:      Bartosz Bekier
   5 // Created:     2009-05-26
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2009 Bartosz Bekier <bartosz.bekier@gmail.com>
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 // For compilers that support precompilation, includes "wx.h".
  12 #include "wx/wxprec.h"
  13
  14 #ifdef __BORLANDC__
  15     #pragma hdrstop
  16 #endif
  17
  18 #if wxUSE_FSWATCHER
  19
  20 #include "wx/fswatcher.h"
  21 #include "wx/private/fswatcher.h"
  22
  23 // ============================================================================
  24 // helpers
  25 // ============================================================================
  26
  27 wxDEFINE_EVENT(wxEVT_FSWATCHER, wxFileSystemWatcherEvent);
  28
  29 static wxString GetFSWEventChangeTypeName(int type)
  30 {
  31     switch (type)
  32     {
  33     case wxFSW_EVENT_CREATE:
  34         return "CREATE";
  35     case wxFSW_EVENT_DELETE:
  36         return "DELETE";
  37     case wxFSW_EVENT_RENAME:
  38         return "RENAME";
  39     case wxFSW_EVENT_MODIFY:
  40         return "MODIFY";
  41     case wxFSW_EVENT_ACCESS:
  42         return "ACCESS";
  43     case wxFSW_EVENT_ATTRIB: // Currently this is wxGTK-only
  44         return "ATTRIBUTE";
  45     }
  46
  47     // should never be reached!
  48     wxFAIL_MSG("Unknown change type");
  49     return "INVALID_TYPE";
  50 }
  51
  52
  53 // ============================================================================
  54 // wxFileSystemWatcherEvent implementation
  55 // ============================================================================
  56
  57 wxString wxFileSystemWatcherEvent::ToString() const
  58 {
  59     return wxString::Format("FSW_EVT type=%d (%s) path='%s'", m_changeType,
  60             GetFSWEventChangeTypeName(m_changeType), GetPath().GetFullPath());
  61 }
  62
  63
  64 // ============================================================================
  65 // wxFileSystemWatcherEvent implementation
  66 // ============================================================================
  67
  68 wxFileSystemWatcherBase::wxFileSystemWatcherBase() :
  69     m_service(0), m_owner(this)
  70 {
  71 }
  72
  73 wxFileSystemWatcherBase::~wxFileSystemWatcherBase()
  74 {
  75     RemoveAll();
  76     if (m_service)
  77     {
  78         delete m_service;
  79     }
  80 }
  81
  82 bool wxFileSystemWatcherBase::Add(const wxFileName& path, int events)
  83 {
  84     wxFSWPathType type = wxFSWPath_None;
  85     if ( path.FileExists() )
  86     {
  87         type = wxFSWPath_File;
  88     }
  89     else if ( path.DirExists() )
  90     {
  91         type = wxFSWPath_Dir;
  92     }
  93     else
  94     {
  95         wxLogError(_("Can't monitor non-existent path \"%s\" for changes."),
  96                    path.GetFullPath());
  97         return false;
  98     }
  99
 100     return AddAny(path, events, type);
 101 }
 102
 103 bool
 104 wxFileSystemWatcherBase::AddAny(const wxFileName& path,
 105                                 int events,
 106                                 wxFSWPathType type,
 107                                 const wxString& filespec)
 108 {
 109     wxString canonical = GetCanonicalPath(path);
 110     if (canonical.IsEmpty())
 111         return false;
 112
 113     // adding a path in a platform specific way
 114     wxFSWatchInfo watch(canonical, events, type, filespec);
 115     if ( !m_service->Add(watch) )
 116         return false;
 117
 118     // on success, either add path to our 'watch-list'
 119     // or, if already watched, inc the refcount. This may happen if
 120     // a dir is Add()ed, then later AddTree() is called on a parent dir
 121     wxFSWatchInfoMap::iterator it = m_watches.find(canonical);
 122     if ( it == m_watches.end() )
 123     {
 124         wxFSWatchInfoMap::value_type val(canonical, watch);
 125         m_watches.insert(val).second;
 126     }
 127     else
 128     {
 129         wxFSWatchInfo& watch = it->second;
 130         int count = watch.IncRef();
 131         wxLogTrace(wxTRACE_FSWATCHER,
 132                    "'%s' is now watched %d times", canonical, count);
 133     }
 134     return true;
 135 }
 136
 137 bool wxFileSystemWatcherBase::Remove(const wxFileName& path)
 138 {
 139     // args validation & consistency checks
 140     wxString canonical = GetCanonicalPath(path);
 141     if (canonical.IsEmpty())
 142         return false;
 143
 144     wxFSWatchInfoMap::iterator it = m_watches.find(canonical);
 145     wxCHECK_MSG(it != m_watches.end(), false,
 146                 wxString::Format("Path '%s' is not watched", canonical));
 147
 148     // Decrement the watch's refcount and remove from watch-list if 0
 149     bool ret = true;
 150     wxFSWatchInfo& watch = it->second;
 151     if ( !watch.DecRef() )
 152     {
 153         // remove in a platform specific way
 154         ret = m_service->Remove(watch);
 155
 156         m_watches.erase(it);
 157     }
 158     return ret;
 159 }
 160
 161 bool wxFileSystemWatcherBase::AddTree(const wxFileName& path, int events,
 162                                       const wxString& filespec)
 163 {
 164     if (!path.DirExists())
 165         return false;
 166
 167     // OPT could be optimised if we stored information about relationships
 168     // between paths
 169     class AddTraverser : public wxDirTraverser
 170     {
 171     public:
 172         AddTraverser(wxFileSystemWatcherBase* watcher, int events,
 173                      const wxString& filespec) :
 174             m_watcher(watcher), m_events(events), m_filespec(filespec)
 175         {
 176         }
 177
 178         virtual wxDirTraverseResult OnFile(const wxString& WXUNUSED(filename))
 179         {
 180             // There is no need to watch individual files as we watch the
 181             // parent directory which will notify us about any changes in them.
 182             return wxDIR_CONTINUE;
 183         }
 184
 185         virtual wxDirTraverseResult OnDir(const wxString& dirname)
 186         {
 187             if ( m_watcher->AddAny(wxFileName::DirName(dirname),
 188                                    m_events, wxFSWPath_Tree, m_filespec) )
 189             {
 190                 wxLogTrace(wxTRACE_FSWATCHER,
 191                    "--- AddTree adding directory '%s' ---", dirname);
 192             }
 193             return wxDIR_CONTINUE;
 194         }
 195
 196     private:
 197         wxFileSystemWatcherBase* m_watcher;
 198         int m_events;
 199         wxString m_filespec;
 200     };
 201
 202     wxDir dir(path.GetFullPath());
 203     // Prevent asserts or infinite loops in trees containing symlinks
 204     int flags = wxDIR_DIRS;
 205     if ( !path.ShouldFollowLink() )
 206     {
 207         flags |= wxDIR_NO_FOLLOW;
 208     }
 209     AddTraverser traverser(this, events, filespec);
 210     dir.Traverse(traverser, filespec, flags);
 211
 212     // Add the path itself explicitly as Traverse() doesn't return it.
 213     AddAny(path.GetPathWithSep(), events, wxFSWPath_Tree, filespec);
 214
 215     return true;
 216 }
 217
 218 bool wxFileSystemWatcherBase::RemoveTree(const wxFileName& path)
 219 {
 220     if (!path.DirExists())
 221         return false;
 222
 223     // OPT could be optimised if we stored information about relationships
 224     // between paths
 225     class RemoveTraverser : public wxDirTraverser
 226     {
 227     public:
 228         RemoveTraverser(wxFileSystemWatcherBase* watcher,
 229                         const wxString& filespec) :
 230             m_watcher(watcher), m_filespec(filespec)
 231         {
 232         }
 233
 234         virtual wxDirTraverseResult OnFile(const wxString& WXUNUSED(filename))
 235         {
 236             // We never watch the individual files when watching the tree, so
 237             // nothing to do here.
 238             return wxDIR_CONTINUE;
 239         }
 240
 241         virtual wxDirTraverseResult OnDir(const wxString& dirname)
 242         {
 243             m_watcher->Remove(wxFileName::DirName(dirname));
 244             return wxDIR_CONTINUE;
 245         }
 246
 247     private:
 248         wxFileSystemWatcherBase* m_watcher;
 249         wxString m_filespec;
 250     };
 251
 252     // If AddTree() used a filespec, we must use the same one
 253     wxString canonical = GetCanonicalPath(path);
 254     wxFSWatchInfoMap::iterator it = m_watches.find(canonical);
 255     wxCHECK_MSG( it != m_watches.end(), false,
 256                  wxString::Format("Path '%s' is not watched", canonical) );
 257     wxFSWatchInfo watch = it->second;
 258     const wxString filespec = watch.GetFilespec();
 259
 260 #if defined(__WINDOWS__)
 261     // When there's no filespec, the wxMSW AddTree() would have set a watch
 262     // on only the passed 'path'. We must therefore remove only this
 263     if (filespec.empty())
 264     {
 265         return Remove(path);
 266     }
 267     // Otherwise fall through to the generic implementation
 268 #endif // __WINDOWS__
 269
 270     wxDir dir(path.GetFullPath());
 271     // AddTree() might have used the wxDIR_NO_FOLLOW to prevent asserts or
 272     // infinite loops in trees containing symlinks. We need to do the same
 273     // or we'll try to remove unwatched items. Let's hope the caller used
 274     // the same ShouldFollowLink() setting as in AddTree()...
 275     int flags = wxDIR_DIRS;
 276     if ( !path.ShouldFollowLink() )
 277     {
 278         flags |= wxDIR_NO_FOLLOW;
 279     }
 280     RemoveTraverser traverser(this, filespec);
 281     dir.Traverse(traverser, filespec, flags);
 282
 283     // As in AddTree() above, handle the path itself explicitly.
 284     Remove(path);
 285
 286     return true;
 287 }
 288
 289 bool wxFileSystemWatcherBase::RemoveAll()
 290 {
 291     m_service->RemoveAll();
 292     m_watches.clear();
 293     return true;
 294 }
 295
 296 int wxFileSystemWatcherBase::GetWatchedPathsCount() const
 297 {
 298     return m_watches.size();
 299 }
 300
 301 int wxFileSystemWatcherBase::GetWatchedPaths(wxArrayString* paths) const
 302 {
 303     wxCHECK_MSG( paths != NULL, -1, "Null array passed to retrieve paths");
 304
 305     wxFSWatchInfoMap::const_iterator it = m_watches.begin();
 306     for ( ; it != m_watches.end(); ++it)
 307     {
 308         paths->push_back(it->first);
 309     }
 310
 311     return m_watches.size();
 312 }
 313
 314 #endif // wxUSE_FSWATCHER