Added PacketWriter class.

src/packet_writer.cpp

@@ -0,0 +1,58 @@
+/*
+ * libtins is a net packet wrapper library for crafting and
+ * interpreting sniffed packets.
+ *
+ * Copyright (C) 2011 Nasel
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+ 
+#ifndef WIN32
+    #include <sys/time.h>
+#endif
+#include <stdexcept>
+#include "packet_writer.h"
+#include "pdu.h"
+
+namespace Tins {
+PacketWriter::PacketWriter(const std::string &file_name, LinkType lt) {
+    handle = pcap_open_dead(lt, 65535);
+    if(!handle)
+        throw std::runtime_error("Error creating pcap handle");
+    dumper = pcap_dump_open(handle, file_name.c_str());
+    if(!dumper) {
+        // RAII plx
+        pcap_close(handle);
+        throw std::runtime_error(pcap_geterr(handle));
+    }
+}
+
+PacketWriter::~PacketWriter() {
+    pcap_dump_close(dumper);
+    pcap_close(handle);
+}
+
+void PacketWriter::write(PDU *pdu) {
+    PDU::serialization_type buffer = pdu->serialize();
+    struct timeval tm;
+    gettimeofday(&tm, 0);
+    struct pcap_pkthdr header = { 
+        tm,
+        buffer.size(),
+        buffer.size()
+    };
+    pcap_dump((u_char*)dumper, &header, &buffer[0]);
+}
+}