Separation of GPRS PCU application from main OpenBTS code and changing PCU architecture (First step).
1. pcu - main program for GPRS PCU.
2. gprs_rlcmac - RLC/MAC layer implementation for PCU. Added list for TBF, TBF allocation, establishment, release.
3. gprs_bssgp_pcu - BSSGP protocol implementation for PCU.
4. pcu_l1_if - interface for communication PCU application with OpenBTS.
diff --git a/pcu_l1_if.cpp b/pcu_l1_if.cpp
new file mode 100644
index 0000000..54c5b36
--- /dev/null
+++ b/pcu_l1_if.cpp
@@ -0,0 +1,91 @@
+/* pcu_l1_if.cpp
+ *
+ * Copyright (C) 2012 Ivan Klyuchnikov
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <Sockets.h>
+#include <gsmtap.h>
+#include <gprs_rlcmac.h>
+#include <Threads.h>
+#include <pcu_l1_if.h>
+
+#define MAX_UDP_LENGTH 1500
+
+// TODO: We should take ports and IP from config.
+UDPSocket pcu_l1if_socket(5070, "127.0.0.1", 5934);
+UDPSocket pcu_gsmtap_socket(5077, "127.0.0.1", 4729);
+
+// Send RLC/MAC block to OpenBTS.
+void pcu_l1if_tx(BitVector * block)
+{
+ char buffer[MAX_UDP_LENGTH];
+ int ofs = 0;
+ block->pack((unsigned char*)&buffer[ofs]);
+ ofs += block->size() >> 3;
+ COUT("Send to OpenBTS: " << *block);
+ pcu_l1if_socket.write(buffer, ofs);
+}
+
+// Recieve RLC/MAC block from OpenBTS.
+void *pcu_l1if_rx(void *)
+{
+ BitVector *block = new BitVector(23*8);
+ pcu_l1if_socket.nonblocking();
+ while (1) {
+ char buf[MAX_UDP_LENGTH];
+ int count = pcu_l1if_socket.read(buf, 3000);
+ if (count>0) {
+ block->unpack((const unsigned char*)buf);
+ COUT("Recieve from OpenBTS (MS): " << *block);
+ gprs_rlcmac_rcv_block(block);
+ }
+ }
+}
+
+void gsmtap_send_llc(uint8_t * data, unsigned len)
+{
+ char buffer[MAX_UDP_LENGTH];
+ int ofs = 0;
+
+ // Build header
+ struct gsmtap_hdr *header = (struct gsmtap_hdr *)buffer;
+ header->version = 2;
+ header->hdr_len = sizeof(struct gsmtap_hdr) >> 2;
+ header->type = 0x08;
+ header->timeslot = 5;
+ header->arfcn = 0;
+ header->signal_dbm = 0;
+ header->snr_db = 0;
+ header->frame_number = 0;
+ header->sub_type = 0;
+ header->antenna_nr = 0;
+ header->sub_slot = 0;
+ header->res = 0;
+
+ ofs += sizeof(*header);
+
+ // Add frame data
+ unsigned j = 0;
+ for (unsigned i = ofs; i < len+ofs; i++)
+ {
+ buffer[i] = (char)data[j];
+ j++;
+ }
+ ofs += len;
+ // Write the GSMTAP packet
+ pcu_gsmtap_socket.write(buffer, ofs);
+}