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