First milestone reached:

File notification now works for Access and Modify of existing files.
Next milestone: Rename and Attrib on existing files.

2 files changed, 93 insertions, 13 deletions

diff --git a/libopie2/opiecore/ofilenotify.cpp b/libopie2/opiecore/ofilenotify.cpp
index bcfb1aa..de4c63b 100644
--- a/libopie2/opiecore/ofilenotify.cpp
+++ b/libopie2/opiecore/ofilenotify.cpp
@@ -1,221 +1,299 @@
 /*
                             This file is part of the Opie Project
              =.             Copyright (C) 2004 Michael 'Mickey' Lauer <mickey@Vanille.de>
            .=l.             Copyright (C) The Opie Team <opie-devel@handhelds.org>
           .>+-=
 _;:,     .>    :=|.         This program is free software; you can
 .> <`_,   >  .   <=         redistribute it and/or  modify it under
 :`=1 )Y*s>-.--   :          the terms of the GNU Library General Public
 .="- .-=="i,     .._        License as published by the Free Software
 - .   .-<_>     .<>         Foundation; either version 2 of the License,
     ._= =}       :          or (at your option) any later version.
    .%`+i>       _;_.
    .i_,=:_.      -<s.       This program is distributed in the hope that
     +  .  -:.       =       it will be useful,  but WITHOUT ANY WARRANTY;
    : ..    .:,     . . .    without even the implied warranty of
    =_        +     =;=|`    MERCHANTABILITY or FITNESS FOR A
  _.=:.       :    :=>`:     PARTICULAR PURPOSE. See the GNU
 ..}^=.=       =       ;     Library General Public License for more
 ++=   -.     .`     .:      details.
 :     =  ...= . :.=-
 -.   .:....=;==+<;          You should have received a copy of the GNU
  -_. . .   )=.  =           Library General Public License along with
    --        :-=`           this library; see the file COPYING.LIB.
                             If not, write to the Free Software Foundation,
                             Inc., 59 Temple Place - Suite 330,
                             Boston, MA 02111-1307, USA.
 */
 
 #include "ofilenotify.h"
 using namespace Opie::Core;
 
 /* OPIE */
 
 /* QT */
 #include <qobject.h>
 #include <qsignal.h>
 #include <qintdict.h>
 #include <qdir.h>
 
 /* STD */
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <assert.h>
 #include <fcntl.h>
 #include <string.h>
 #include <errno.h>
 #include <unistd.h>
 
 static QIntDict<OFileNotification> notification_list;
 
 namespace Opie {
 namespace Core {
 
 OFileNotification::OFileNotification( QObject* parent, const char* name )
                   :QObject( parent, name ), _active( false )
 {
     qDebug( "OFileNotification::OFileNotification()" );
 }
 
 
 OFileNotification::~OFileNotification()
 {
     qDebug( "OFileNotification::~OFileNotification()" );
 }
 
 
 bool OFileNotification::isActive() const
 {
     return _active;
 }
 
 
 int OFileNotification::start( const QString& path, bool sshot, OFileNotificationType type )
 {
     _path = QString::null;
     _fd = 0;
     if ( _active ) stop();
+    QString dirpath;
 
-    int fd = ::open( (const char*) path, O_RDONLY );
+    // check if path exists and whether it is a file or a directory, if it exists at all
+    int result = ::stat( (const char*) path, &_stat );
+    if ( result == -1 )
+    {
+        qWarning( "OFileNotification::start(): Can't stat '%s': %s.", (const char*) path, strerror( errno ) );
+        return -1;
+    }
+
+    // if it is not a directory, we need to find out in which directory the file is
+    bool isDirectory = S_ISDIR( _stat.st_mode );
+    if ( !isDirectory )
+    {
+        int slashpos;
+        slashpos = path.findRev( '/' );
+        if ( slashpos > 0 )
+        {
+            _path = path;
+            dirpath = path.left( slashpos );
+        }
+    }
+    else /* isDirectory */
+    {
+        qWarning( "FIXME FIXME FIXME = Directory Notification Not Yet Implemented!" );
+        _path = path;
+        dirpath = path;
+        assert( 0 );
+    }
+
+    int fd = ::open( (const char*) dirpath, O_RDONLY );
     if ( fd != -1 )
     {
         if ( notification_list.isEmpty() )
         {
             OFileNotification::registerSignalHandler();
         }
-        int result = ::fcntl( fd, F_SETSIG, SIGRTMIN );
+
+        result = ::fcntl( fd, F_SETSIG, SIGRTMIN );
         if ( result == -1 )
         {
-            qWarning( "OFileNotification::start(): Can't subscribe to '%s': %s.", (const char*) path, strerror( errno ) );
+            qWarning( "OFileNotification::start(): Can't subscribe to '%s': %s.", (const char*) dirpath, strerror( errno ) );
             return -1;
         }
         if ( !sshot ) (int) type |= (int) Multi;
         result = ::fcntl( fd, F_NOTIFY, type );
         if ( result == -1 )
         {
-            qWarning( "OFileNotification::start(): Can't subscribe to '%s': %s.", (const char*) path, strerror( errno ) );
+            qWarning( "OFileNotification::start(): Can't subscribe to '%s': %s.", (const char*) dirpath, strerror( errno ) );
             return -1;
         }
-        qDebug( "OFileNotification::start(): Subscribed for changes to %s (fd = %d, mask = 0x%0x)", (const char*) path, fd, type );
+        qDebug( "OFileNotification::start(): Subscribed for changes to %s (fd = %d, mask = 0x%0x)", (const char*) dirpath, fd, type );
         notification_list.insert( fd, this );
         _type = type;
-        _path = path;
         _fd = fd;
+        _active = true;
+        ::memset( &_stat, 0, sizeof _stat );
+        ::stat( _path, &_stat );
         return fd;
     }
     else
     {
-        qWarning( "OFileNotification::start(): Error with path '%s': %s.", (const char*) path, strerror( errno ) );
+        qWarning( "OFileNotification::start(): Error with path '%s': %s.", (const char*) dirpath, strerror( errno ) );
         return -1;
     }
 }
 
 
 void OFileNotification::stop()
 {
     if ( !_active ) return;
 
     int result = ::fcntl( _fd, F_NOTIFY, 0 );
     if ( result == -1 )
     {
         qWarning( "OFileNotification::stop(): Can't remove subscription to '%s': %s.", (const char*) _path, strerror( errno ) );
     }
     else
     {
         ::close( _fd );
         _type = Single;
         _path = QString::null;
         _fd = 0;
         _active = false;
     }
 }
 
 
 OFileNotificationType OFileNotification::type() const
 {
     return _type;
 }
 
 
 QString OFileNotification::path() const
 {
     return _path;
 }
 
+
 int OFileNotification::fileno() const
 {
     return _fd;
 }
 
-void OFileNotification::activate()
+
+bool OFileNotification::activate()
 {
-    emit triggered();
-    _signal.activate();
+    if ( hasChanged() )
+    {
+        emit triggered();
+        _signal.activate();
+        return true;
+    }
+    else
+        return false;
+}
+
+
+bool OFileNotification::hasChanged()
+{
+    bool c = false;
+
+    struct stat newstat;
+    ::memset( &newstat, 0, sizeof newstat );
+    ::stat( _path, &newstat );
+
+    qDebug( "stat.atime = %0lx, newstat.atime = %0lx", (long)_stat.st_atime, (long)newstat.st_atime );
+    qDebug( "stat.mtime = %0lx, newstat.mtime = %0lx", (long)_stat.st_mtime, (long)newstat.st_mtime );
+    if ( !c && (_type & Access) && (long)_stat.st_atime < (long)newstat.st_atime )
+    {
+        qDebug( "OFileNotification::hasChanged(): atime changed" );
+        c = true;
+    }
+    if ( !c && (_type & Modify) && (long)_stat.st_mtime < (long)newstat.st_mtime )
+    {
+        qDebug( "OFileNotification::hasChanged(): mtime changed" );
+        c = true;
+    }
+
+    return c;
 }
 
 
 void OFileNotification::singleShot( const QString& path, QObject* receiver, const char* member, OFileNotificationType type )
 {
     OFileNotification* ofn = new OFileNotification();
     ofn->_signal.connect( receiver, member );
     ofn->start( path, true, type );
 }
 
 
 void OFileNotification::__signalHandler( int sig, siginfo_t *si, void *data )
 {
     qWarning( "OFileNotification::__signalHandler(): reached." );
     int fd = si->si_fd;
     OFileNotification* fn = notification_list[fd];
     if ( fn )
     {
-        fn->activate();
+        // check if it really was the file (dnotify triggers on directory granularity, not file granularity)
+        if ( !fn->activate() )
+        {
+            qDebug( "OFileNotification::__signalHandler(): false alarm ;) Restarting the trigger (if it was single)..." );
+            if ( !(fn->type() & Multi ) )
+            {
+                int result = ::fcntl( fn->fileno(), F_NOTIFY, fn->type() );
+                if ( result == -1 )
+                {
+                    qWarning( "OFileNotification::__signalHandler(): Can't restart the trigger: %s.", strerror( errno ) );
+                }
+            }
+            return;
+        }
         #if 1
         if ( !(fn->type() & Multi) )
         {
             qDebug( "OFileNotification::__signalHandler(): '%d' was singleShot. Removing from list.", fd );
             notification_list.remove( fd );
             if ( notification_list.isEmpty() )
             {
                 OFileNotification::unregisterSignalHandler();
             }
         }
         #endif
     }
     else
     {
         qWarning( "OFileNotification::__signalHandler(): D'oh! Called without fd in notification_list. Race condition?" );
     }
 }
 
 
 bool OFileNotification::registerSignalHandler()
 {
     struct sigaction act;
     act.sa_sigaction = OFileNotification::__signalHandler;
     ::sigemptyset( &act.sa_mask );
     act.sa_flags = SA_SIGINFO;
     if ( ::sigaction( SIGRTMIN, &act, NULL ) == -1 )
     {
         qWarning( "OFileNotification::registerSignalHandler(): couldn't register signal handler: %s", strerror( errno ) );
         return false;
     }
     qDebug( "OFileNotification::registerSignalHandler(): done" );
 }
 
 
 void OFileNotification::unregisterSignalHandler()
 {
     struct sigaction act;
     act.sa_sigaction = ( void (*)(int, siginfo_t*, void*) ) SIG_DFL;
     ::sigemptyset( &act.sa_mask );
     if ( ::sigaction( SIGRTMIN, &act, NULL ) == -1 )
-    if ( ::sigaction( SIGRTMIN, &act, NULL ) == -1 )
     {
         qWarning( "OFileNotification::unregisterSignalHandler(): couldn't deregister signal handler: %s", strerror( errno ) );
     }
     qDebug( "OFileNotification::unregisterSignalHandler(): done" );
 }
 
 
 }
 }
diff --git a/libopie2/opiecore/ofilenotify.h b/libopie2/opiecore/ofilenotify.h
index 3bc141d..5315896 100644
--- a/libopie2/opiecore/ofilenotify.h
+++ b/libopie2/opiecore/ofilenotify.h
@@ -30,66 +30,68 @@ _;:,     .>    :=|.         This program is free software; you can
 #define OFILENOTIFY_H
 #if defined (__GNUC__) && (__GNUC__ < 3)
 #define _GNU_SOURCE
 #endif
 
 /* QT */
 #include <qobject.h>
 #include <qsignal.h>
 #include <qstring.h>
 
 /* STD */
 #include <signal.h>
 #include <fcntl.h>
 
 namespace Opie {
 namespace Core {
 
 enum OFileNotificationType { Single = 0x0000000,
                              Multi  = DN_MULTISHOT,
                              Access = DN_ACCESS,
                              Modify = DN_MODIFY,
                              Create = DN_CREATE,
                              Delete = DN_DELETE,
                              Rename = DN_RENAME,
                              Attrib = DN_ATTRIB };
 
 class OFileNotification : public QObject
 {
   Q_OBJECT
 
   public:
     OFileNotification( QObject* parent = 0, const char* name = 0 );
     ~OFileNotification();
 
     static void singleShot( const QString& path, QObject* receiver, const char* member, OFileNotificationType type = Modify );
 
     int start( const QString& path, bool sshot = false, OFileNotificationType type = Modify );
     void stop();
 
     OFileNotificationType type() const;
     QString path() const;
     int fileno() const;
     bool isActive() const;
 
   signals:
     void triggered();
 
   protected:
-    void activate();
+    bool activate();
+    bool hasChanged();
     static bool registerSignalHandler();
     static void unregisterSignalHandler();
     static void __signalHandler( int sig, siginfo_t *si, void *data );
 
   private:
     QString _path;
     OFileNotificationType _type;
     QSignal _signal;
     int _fd;
     bool _active;
+    struct stat _stat;
 };
 
 }
 }
 
 #endif