samples/fswatcher/fswatcher.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        samples/fswatcher/fswatcher.cpp
   3 // Purpose:     wxFileSystemWatcher sample
   4 // Author:      Bartosz Bekier
   5 // Created:     2009-06-27
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) Bartosz Bekier
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 #include "wx/wxprec.h"
  12
  13 #ifdef __BORLANDC__
  14     #pragma hdrstop
  15 #endif
  16 #ifndef WX_PRECOMP
  17     #include "wx/wx.h"
  18 #endif
  19
  20 #ifndef wxHAS_IMAGES_IN_RESOURCES
  21     #include "../sample.xpm"
  22 #endif
  23
  24 #include "wx/fswatcher.h"
  25 #include "wx/listctrl.h"
  26 #include "wx/cmdline.h"
  27
  28 // Define a new frame type: this is going to be our main frame
  29 class MyFrame : public wxFrame
  30 {
  31 public:
  32     MyFrame(const wxString& title);
  33     virtual ~MyFrame();
  34
  35     // Add an entry of the specified type asking the user for the filename if
  36     // the one passed to this function is empty.
  37     void AddEntry(wxFSWPathType type, wxString filename = wxString());
  38
  39     bool CreateWatcherIfNecessary();
  40
  41 private:
  42     // file system watcher creation
  43     void CreateWatcher();
  44
  45     // event handlers
  46     void OnClear(wxCommandEvent& WXUNUSED(event)) { m_evtConsole->Clear(); }
  47     void OnQuit(wxCommandEvent& WXUNUSED(event)) { Close(true); }
  48     void OnWatch(wxCommandEvent& event);
  49     void OnFollowLinks(wxCommandEvent& event);
  50     void OnAbout(wxCommandEvent& event);
  51
  52     void OnAdd(wxCommandEvent& event);
  53     void OnAddTree(wxCommandEvent& event);
  54     void OnRemove(wxCommandEvent& event);
  55     void OnRemoveUpdateUI(wxUpdateUIEvent& event);
  56
  57     void OnFileSystemEvent(wxFileSystemWatcherEvent& event);
  58     void LogEvent(const wxFileSystemWatcherEvent& event);
  59
  60     wxTextCtrl *m_evtConsole;         // events console
  61     wxListView *m_filesList;          // list of watched paths
  62     wxFileSystemWatcher* m_watcher;   // file system watcher
  63     bool m_followLinks;               // should symlinks be dereferenced
  64
  65     const static wxString LOG_FORMAT; // how to format events
  66 };
  67
  68 const wxString MyFrame::LOG_FORMAT = " %-12s %-36s    %-36s";
  69
  70 // Define a new application type, each program should derive a class from wxApp
  71 class MyApp : public wxApp
  72 {
  73 public:
  74     // 'Main program' equivalent: the program execution "starts" here
  75     virtual bool OnInit()
  76     {
  77         if ( !wxApp::OnInit() )
  78             return false;
  79
  80         wxLog::AddTraceMask("EventSource");
  81         wxLog::AddTraceMask(wxTRACE_FSWATCHER);
  82
  83         // create the main application window
  84         m_frame = new MyFrame("File System Watcher wxWidgets App");
  85
  86         // If we returned false here, the application would exit immediately.
  87         return true;
  88     }
  89
  90     // create the file system watcher here, because it needs an active loop
  91     virtual void OnEventLoopEnter(wxEventLoopBase* WXUNUSED(loop))
  92     {
  93         if ( m_frame->CreateWatcherIfNecessary() )
  94         {
  95             if ( !m_dirToWatch.empty() )
  96                 m_frame->AddEntry(wxFSWPath_Dir, m_dirToWatch);
  97         }
  98     }
  99
 100     virtual void OnInitCmdLine(wxCmdLineParser& parser)
 101     {
 102         wxApp::OnInitCmdLine(parser);
 103         parser.AddParam("directory to watch",
 104                         wxCMD_LINE_VAL_STRING,
 105                         wxCMD_LINE_PARAM_OPTIONAL);
 106     }
 107
 108     virtual bool OnCmdLineParsed(wxCmdLineParser& parser)
 109     {
 110         if ( !wxApp::OnCmdLineParsed(parser) )
 111             return false;
 112
 113         if ( parser.GetParamCount() )
 114             m_dirToWatch = parser.GetParam();
 115
 116         return true;
 117     }
 118
 119 private:
 120     MyFrame *m_frame;
 121
 122     // The directory to watch if specified on the command line.
 123     wxString m_dirToWatch;
 124 };
 125
 126 // Create a new application object: this macro will allow wxWidgets to create
 127 // the application object during program execution (it's better than using a
 128 // static object for many reasons) and also declares the accessor function
 129 // wxGetApp() which will return the reference of the right type (i.e. MyApp and
 130 // not wxApp)
 131 IMPLEMENT_APP(MyApp)
 132
 133
 134 // ============================================================================
 135 // implementation
 136 // ============================================================================
 137
 138 // frame constructor
 139 MyFrame::MyFrame(const wxString& title)
 140     : wxFrame(NULL, wxID_ANY, title),
 141       m_watcher(NULL), m_followLinks(false)
 142 {
 143     SetIcon(wxICON(sample));
 144
 145     // IDs for menu and buttons
 146     enum
 147     {
 148         MENU_ID_QUIT = wxID_EXIT,
 149         MENU_ID_CLEAR = wxID_CLEAR,
 150         MENU_ID_WATCH = 101,
 151         MENU_ID_DEREFERENCE,
 152
 153         BTN_ID_ADD = 200,
 154         BTN_ID_ADD_TREE,
 155         BTN_ID_REMOVE
 156     };
 157
 158     // ================================================================
 159     // menu
 160
 161     // create a menu bar
 162     wxMenu *menuFile = new wxMenu;
 163     menuFile->Append(MENU_ID_CLEAR, "&Clear log\tCtrl-L");
 164     menuFile->AppendSeparator();
 165     menuFile->Append(MENU_ID_QUIT, "E&xit\tAlt-X", "Quit this program");
 166
 167     // "Watch" menu
 168     wxMenu *menuMon = new wxMenu;
 169     wxMenuItem* it = menuMon->AppendCheckItem(MENU_ID_WATCH, "&Watch\tCtrl-W");
 170     // started by default, because file system watcher is started by default
 171     it->Check(true);
 172
 173 #if defined(__UNIX__)
 174     // Let the user decide whether to dereference symlinks. If he makes the
 175     // wrong choice, asserts will occur if the symlink target is also watched
 176     it = menuMon->AppendCheckItem(MENU_ID_DEREFERENCE,
 177                                   "&Follow symlinks\tCtrl-F",
 178                                   _("If checked, dereference symlinks")
 179                                  );
 180     it->Check(false);
 181     Connect(MENU_ID_DEREFERENCE, wxEVT_COMMAND_MENU_SELECTED,
 182             wxCommandEventHandler(MyFrame::OnFollowLinks));
 183 #endif // __UNIX__
 184
 185     // the "About" item should be in the help menu
 186     wxMenu *menuHelp = new wxMenu;
 187     menuHelp->Append(wxID_ABOUT, "&About\tF1", "Show about dialog");
 188
 189     // now append the freshly created menu to the menu bar...
 190     wxMenuBar *menuBar = new wxMenuBar();
 191     menuBar->Append(menuFile, "&File");
 192     menuBar->Append(menuMon, "&Watch");
 193     menuBar->Append(menuHelp, "&Help");
 194
 195     // ... and attach this menu bar to the frame
 196     SetMenuBar(menuBar);
 197
 198     // ================================================================
 199     // upper panel
 200
 201     // panel
 202     wxPanel *panel = new wxPanel(this);
 203     wxSizer *panelSizer = new wxGridSizer(2);
 204     wxBoxSizer *leftSizer = new wxBoxSizer(wxVERTICAL);
 205
 206     // label
 207     wxStaticText* label = new wxStaticText(panel, wxID_ANY, "Watched paths");
 208     leftSizer->Add(label, wxSizerFlags().Center().Border(wxALL));
 209
 210     // list of files
 211     m_filesList = new wxListView(panel, wxID_ANY, wxPoint(-1,-1),
 212                                  wxSize(300,200), wxLC_LIST | wxLC_SINGLE_SEL);
 213     leftSizer->Add(m_filesList, wxSizerFlags(1).Expand());
 214
 215     // buttons
 216     wxButton* buttonAdd = new wxButton(panel, BTN_ID_ADD, "&Add");
 217     wxButton* buttonAddTree = new wxButton(panel, BTN_ID_ADD_TREE, "Add &tree");
 218     wxButton* buttonRemove = new wxButton(panel, BTN_ID_REMOVE, "&Remove");
 219     wxSizer *btnSizer = new wxGridSizer(2);
 220     btnSizer->Add(buttonAdd, wxSizerFlags().Center().Border(wxALL));
 221     btnSizer->Add(buttonAddTree, wxSizerFlags().Center().Border(wxALL));
 222     btnSizer->Add(buttonRemove, wxSizerFlags().Center().Border(wxALL));
 223
 224     // and put it all together
 225     leftSizer->Add(btnSizer, wxSizerFlags(0).Expand());
 226     panelSizer->Add(leftSizer, wxSizerFlags(1).Expand());
 227     panel->SetSizerAndFit(panelSizer);
 228
 229     // ================================================================
 230     // lower panel
 231
 232     wxTextCtrl *headerText = new wxTextCtrl(this, wxID_ANY, "",
 233                                             wxDefaultPosition, wxDefaultSize,
 234                                             wxTE_READONLY);
 235     wxString h = wxString::Format(LOG_FORMAT, "event", "path", "new path");
 236     headerText->SetValue(h);
 237
 238     // event console
 239     m_evtConsole = new wxTextCtrl(this, wxID_ANY, "",
 240                                wxDefaultPosition, wxSize(200,200),
 241                                wxTE_MULTILINE|wxTE_READONLY|wxHSCROLL);
 242
 243     // set monospace font to have output in nice columns
 244     wxFont font(9, wxFONTFAMILY_TELETYPE,
 245                 wxFONTSTYLE_NORMAL, wxFONTWEIGHT_NORMAL);
 246     headerText->SetFont(font);
 247     m_evtConsole->SetFont(font);
 248
 249     // ================================================================
 250     // laying out whole frame
 251
 252     wxBoxSizer *sizer = new wxBoxSizer(wxVERTICAL);
 253     sizer->Add(panel, wxSizerFlags(1).Expand());
 254     sizer->Add(headerText, wxSizerFlags().Expand());
 255     sizer->Add(m_evtConsole, wxSizerFlags(1).Expand());
 256     SetSizerAndFit(sizer);
 257
 258     // set size and position on screen
 259     SetSize(800, 600);
 260     CentreOnScreen();
 261
 262     // ================================================================
 263     // event handlers & show
 264
 265     // menu
 266     Connect(MENU_ID_CLEAR, wxEVT_COMMAND_MENU_SELECTED,
 267             wxCommandEventHandler(MyFrame::OnClear));
 268     Connect(MENU_ID_QUIT, wxEVT_COMMAND_MENU_SELECTED,
 269             wxCommandEventHandler(MyFrame::OnQuit));
 270     Connect(MENU_ID_WATCH, wxEVT_COMMAND_MENU_SELECTED,
 271             wxCommandEventHandler(MyFrame::OnWatch));
 272     Connect(wxID_ABOUT, wxEVT_COMMAND_MENU_SELECTED,
 273             wxCommandEventHandler(MyFrame::OnAbout));
 274
 275     // buttons
 276     Connect(BTN_ID_ADD, wxEVT_COMMAND_BUTTON_CLICKED,
 277             wxCommandEventHandler(MyFrame::OnAdd));
 278     Connect(BTN_ID_ADD_TREE, wxEVT_COMMAND_BUTTON_CLICKED,
 279             wxCommandEventHandler(MyFrame::OnAddTree));
 280     Connect(BTN_ID_REMOVE, wxEVT_COMMAND_BUTTON_CLICKED,
 281             wxCommandEventHandler(MyFrame::OnRemove));
 282     Connect(BTN_ID_REMOVE, wxEVT_UPDATE_UI,
 283             wxUpdateUIEventHandler(MyFrame::OnRemoveUpdateUI));
 284
 285     // and show itself (the frames, unlike simple controls, are not shown when
 286     // created initially)
 287     Show(true);
 288 }
 289
 290 MyFrame::~MyFrame()
 291 {
 292     delete m_watcher;
 293 }
 294
 295 bool MyFrame::CreateWatcherIfNecessary()
 296 {
 297     if (m_watcher)
 298         return false;
 299
 300     CreateWatcher();
 301     Connect(wxEVT_FSWATCHER,
 302             wxFileSystemWatcherEventHandler(MyFrame::OnFileSystemEvent));
 303
 304     return true;
 305 }
 306
 307 void MyFrame::CreateWatcher()
 308 {
 309     wxCHECK_RET(!m_watcher, "Watcher already initialized");
 310     m_watcher = new wxFileSystemWatcher();
 311     m_watcher->SetOwner(this);
 312 }
 313
 314 // ============================================================================
 315 // event handlers
 316 // ============================================================================
 317
 318 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 319 {
 320     wxMessageBox("Demonstrates the usage of file system watcher, "
 321                  "the wxWidgets monitoring system notifying you of "
 322                  "changes done to your files.\n"
 323                  "(c) 2009 Bartosz Bekier\n",
 324                  "About wxWidgets File System Watcher Sample",
 325                  wxOK | wxICON_INFORMATION, this);
 326 }
 327
 328 void MyFrame::OnWatch(wxCommandEvent& event)
 329 {
 330     wxLogDebug("%s start=%d", __WXFUNCTION__, event.IsChecked());
 331
 332     if (event.IsChecked())
 333     {
 334         wxCHECK_RET(!m_watcher, "Watcher already initialized");
 335         CreateWatcher();
 336     }
 337     else
 338     {
 339         wxCHECK_RET(m_watcher, "Watcher not initialized");
 340         m_filesList->DeleteAllItems();
 341         wxDELETE(m_watcher);
 342     }
 343 }
 344
 345 void MyFrame::OnFollowLinks(wxCommandEvent& event)
 346 {
 347     m_followLinks = event.IsChecked();
 348 }
 349
 350 void MyFrame::OnAdd(wxCommandEvent& WXUNUSED(event))
 351 {
 352     AddEntry(wxFSWPath_Dir);
 353 }
 354
 355 void MyFrame::OnAddTree(wxCommandEvent& WXUNUSED(event))
 356 {
 357     AddEntry(wxFSWPath_Tree);
 358 }
 359
 360 void MyFrame::AddEntry(wxFSWPathType type, wxString filename)
 361 {
 362     if ( filename.empty() )
 363     {
 364         // TODO account for adding the files as well
 365         filename = wxDirSelector("Choose a folder to watch", "",
 366                                  wxDD_DEFAULT_STYLE | wxDD_DIR_MUST_EXIST);
 367         if ( filename.empty() )
 368             return;
 369     }
 370
 371     wxCHECK_RET(m_watcher, "Watcher not initialized");
 372
 373     wxLogDebug("Adding %s: '%s'",
 374                filename,
 375                type == wxFSWPath_Dir ? "directory" : "directory tree");
 376
 377     wxString prefix;
 378     bool ok = false;
 379
 380     // This will tell wxFileSystemWatcher whether to dereference symlinks
 381     wxFileName fn = wxFileName::DirName(filename);
 382     if (!m_followLinks)
 383     {
 384         fn.DontFollowLink();
 385     }
 386
 387     switch ( type )
 388     {
 389         case wxFSWPath_Dir:
 390             ok = m_watcher->Add(fn);
 391             prefix = "Dir:  ";
 392             break;
 393
 394         case wxFSWPath_Tree:
 395             ok = m_watcher->AddTree(fn);
 396             prefix = "Tree: ";
 397             break;
 398
 399         case wxFSWPath_File:
 400         case wxFSWPath_None:
 401             wxFAIL_MSG( "Unexpected path type." );
 402     }
 403
 404     if (!ok)
 405     {
 406         wxLogError("Error adding '%s' to watched paths", filename);
 407         return;
 408     }
 409
 410     // Prepend 'prefix' to the filepath, partly for display
 411     // but mostly so that OnRemove() can work out the correct way to remove it
 412     m_filesList->InsertItem(m_filesList->GetItemCount(),
 413                             prefix + wxFileName::DirName(filename).GetFullPath());
 414 }
 415
 416 void MyFrame::OnRemove(wxCommandEvent& WXUNUSED(event))
 417 {
 418     wxCHECK_RET(m_watcher, "Watcher not initialized");
 419     long idx = m_filesList->GetFirstSelected();
 420     if (idx == -1)
 421         return;
 422
 423     bool ret;
 424     wxString path = m_filesList->GetItemText(idx).Mid(6);
 425
 426     // This will tell wxFileSystemWatcher whether to dereference symlinks
 427     wxFileName fn = wxFileName::DirName(path);
 428     if (!m_followLinks)
 429     {
 430         fn.DontFollowLink();
 431     }
 432
 433     // TODO we know it is a dir, but it doesn't have to be
 434     if (m_filesList->GetItemText(idx).StartsWith("Dir:  "))
 435     {
 436         ret = m_watcher->Remove(fn);
 437     }
 438     else if (m_filesList->GetItemText(idx).StartsWith("Tree: "))
 439     {
 440         ret = m_watcher->RemoveTree(fn);
 441     }
 442     else
 443     {
 444         wxFAIL_MSG("Unexpected item in wxListView.");
 445     }
 446
 447     if (!ret)
 448     {
 449         wxLogError("Error removing '%s' from watched paths", path);
 450     }
 451     else
 452     {
 453         m_filesList->DeleteItem(idx);
 454     }
 455 }
 456
 457 void MyFrame::OnRemoveUpdateUI(wxUpdateUIEvent& event)
 458 {
 459     event.Enable(m_filesList->GetFirstSelected() != wxNOT_FOUND);
 460 }
 461
 462 void MyFrame::OnFileSystemEvent(wxFileSystemWatcherEvent& event)
 463 {
 464     // TODO remove when code is rock-solid
 465     wxLogTrace(wxTRACE_FSWATCHER, "*** %s ***", event.ToString());
 466     LogEvent(event);
 467
 468     int type = event.GetChangeType();
 469     if ((type == wxFSW_EVENT_DELETE) || (type == wxFSW_EVENT_RENAME))
 470     {
 471         // If path is one of our watched dirs, we need to react to this
 472         // otherwise there'll be asserts if later we try to remove it
 473         wxString eventpath = event.GetPath().GetFullPath();
 474         bool found(false);
 475         for (size_t n = m_filesList->GetItemCount(); n > 0; --n)
 476         {
 477             wxString path, foo = m_filesList->GetItemText(n-1);
 478             if ((!m_filesList->GetItemText(n-1).StartsWith("Dir:  ", &path)) &&
 479                 (!m_filesList->GetItemText(n-1).StartsWith("Tree: ", &path)))
 480             {
 481                 wxFAIL_MSG("Unexpected item in wxListView.");
 482             }
 483             if (path == eventpath)
 484             {
 485                 if (type == wxFSW_EVENT_DELETE)
 486                 {
 487                     m_filesList->DeleteItem(n-1);
 488                 }
 489                 else
 490                 {
 491                     // At least in wxGTK, we'll never get here: renaming the top
 492                     // watched dir gives IN_MOVE_SELF and no new-name info.
 493                     // However I'll leave the code in case other platforms do
 494                     wxString newname = event.GetNewPath().GetFullPath();
 495                     if (newname.empty() ||
 496                         newname == event.GetPath().GetFullPath())
 497                     {
 498                         // Just in case either of these are possible...
 499                         wxLogTrace(wxTRACE_FSWATCHER,
 500                                    "Invalid attempt to rename to %s", newname);
 501                         return;
 502                     }
 503                     wxString prefix =
 504                         m_filesList->GetItemText(n-1).StartsWith("Dir:  ") ?
 505                                       "Dir:  " : "Tree: ";
 506                     m_filesList->SetItemText(n-1, prefix + newname);
 507                 }
 508                 found = true;
 509                 // Don't break: a filepath may have been added more than once
 510             }
 511         }
 512
 513         if (found)
 514         {
 515             wxString msg = wxString::Format(
 516                            "Your watched path %s has been deleted or renamed\n",
 517                            eventpath);
 518             m_evtConsole->AppendText(msg);
 519         }
 520     }
 521 }
 522
 523
 524 static wxString GetFSWEventChangeTypeName(int changeType)
 525 {
 526     switch (changeType)
 527     {
 528     case wxFSW_EVENT_CREATE:
 529         return "CREATE";
 530     case wxFSW_EVENT_DELETE:
 531         return "DELETE";
 532     case wxFSW_EVENT_RENAME:
 533         return "RENAME";
 534     case wxFSW_EVENT_MODIFY:
 535         return "MODIFY";
 536     case wxFSW_EVENT_ACCESS:
 537         return "ACCESS";
 538     }
 539
 540     return "INVALID_TYPE";
 541 }
 542
 543 void MyFrame::LogEvent(const wxFileSystemWatcherEvent& event)
 544 {
 545     wxString entry = wxString::Format(LOG_FORMAT + "\n",
 546                             GetFSWEventChangeTypeName(event.GetChangeType()),
 547                             event.GetPath().GetFullPath(),
 548                             event.GetNewPath().GetFullPath());
 549     m_evtConsole->AppendText(entry);
 550 }