1 files changed, 105 insertions, 0 deletions
diff --git a/tdeio/tdeio/klimitediodevice.h b/tdeio/tdeio/klimitediodevice.h
new file mode 100644
index 000000000..602ba45a0
--- /dev/null
+++ b/tdeio/tdeio/klimitediodevice.h
@@ -0,0 +1,105 @@
+/* This file is part of the KDE libraries
+   Copyright (C) 2001, 2002 David Faure <david@mandrakesoft.com>
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public
+   License version 2 as published by the Free Software Foundation.
+
+   This library 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., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.
+*/
+
+#ifndef klimitediodevice_h
+#define klimitediodevice_h
+
+#include <kdebug.h>
+#include <tqiodevice.h>
+/**
+ * A readonly device that reads from an underlying device
+ * from a given point to another (e.g. to give access to a single
+ * file inside an archive).
+ * @author David Faure <david@mandrakesoft.com>
+ * @since 3.1
+ */
+class TDEIO_EXPORT KLimitedIODevice : public TQIODevice
+{
+public:
+    /**
+     * Creates a new KLimitedIODevice.
+     * @param dev the underlying device, opened or not
+     * This device itself auto-opens (in readonly mode), no need to open it.
+     * @param start where to start reading (position in bytes)
+     * @param length the length of the data to read (in bytes)
+     */
+    KLimitedIODevice( TQIODevice *dev, int start, int length )
+        : m_dev( dev ), m_start( start ), m_length( length )
+    {
+        //kdDebug(7005) << "KLimitedIODevice::KLimitedIODevice start=" << start << " length=" << length << endl;
+        setType( IO_Direct ); // we support sequential too, but then atEnd() tries getch/ungetch !
+        open( IO_ReadOnly );
+    }
+    virtual ~KLimitedIODevice() {}
+
+    virtual bool open( TQ_OpenMode m ) {
+        //kdDebug(7005) << "KLimitedIODevice::open m=" << m << endl;
+        if ( m & IO_ReadOnly ) {
+            /*bool ok = false;
+            if ( m_dev->isOpen() )
+                ok = ( m_dev->mode() == IO_ReadOnly );
+            else
+                ok = m_dev->open( m );
+            if ( ok )*/
+                m_dev->at( m_start ); // No concurrent access !
+        }
+        else
+            kdWarning(7005) << "KLimitedIODevice::open only supports IO_ReadOnly!" << endl;
+        setState( IO_Open );
+        setMode( m );
+        return true;
+    }
+    virtual void close() {}
+    virtual void flush() {}
+
+#ifdef USE_QT4
+    virtual qint64 size() const { return m_length; }
+#else // USE_QT4
+    virtual Offset size() const { return m_length; }
+#endif // USE_QT4
+
+    virtual TQT_TQIO_LONG tqreadBlock ( char * data, TQT_TQIO_ULONG maxlen )
+    {
+        maxlen = TQMIN( maxlen, m_length - at() ); // Apply upper limit
+        return m_dev->readBlock( data, maxlen );
+    }
+    virtual TQT_TQIO_LONG tqwriteBlock ( const char *, TQT_TQIO_ULONG ) { return -1; } // unsupported
+    virtual int putch( int ) { return -1; } // unsupported
+
+    virtual int getch() {
+        char c[2];
+        if ( tqreadBlock(c, 1) == -1)
+            return -1;
+        else
+            return c[0];
+    }
+    virtual int ungetch( int c ) { return m_dev->ungetch(c); } // ## apply lower limit ?
+    virtual Offset at() const { return m_dev->at() - m_start; }
+    virtual bool at( Offset pos ) {
+        Q_ASSERT( pos <= m_length );
+        pos = QMIN( pos, m_length ); // Apply upper limit
+        return m_dev->at( m_start + pos );
+    }
+    virtual bool atEnd() const { return m_dev->atEnd() || m_dev->at() >= m_start + m_length; }
+private:
+    TQIODevice* m_dev;
+    TQ_ULONG m_start;
+    TQ_ULONG m_length;
+};
+
+#endif