1 files changed, 154 insertions, 0 deletions
diff --git a/host/lib/transport/udp_zero_copy_asio.cpp b/host/lib/transport/udp_zero_copy_asio.cpp
new file mode 100644
index 000000000..219ae8720
--- /dev/null
+++ b/host/lib/transport/udp_zero_copy_asio.cpp
@@ -0,0 +1,154 @@
+//
+// Copyright 2010 Ettus Research LLC
+//
+// 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 3 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, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/transport/udp_zero_copy.hpp>
+#include <boost/cstdint.hpp>
+#include <boost/thread.hpp>
+#include <boost/format.hpp>
+#include <iostream>
+
+using namespace uhd::transport;
+
+/***********************************************************************
+ * Smart buffer implementation for udp zerocopy none
+ *
+ * This smart buffer implemention houses a const buffer.
+ * When the smart buffer is deleted, the buffer is freed.
+ * The memory in the const buffer is allocated with new [],
+ * and so the destructor frees the buffer with delete [].
+ **********************************************************************/
+class smart_buffer_impl : public smart_buffer{
+public:
+    smart_buffer_impl(const boost::asio::const_buffer &buff){
+        _buff = buff;
+    }
+
+    ~smart_buffer_impl(void){
+        delete [] boost::asio::buffer_cast<const boost::uint32_t *>(_buff);
+    }
+
+    const boost::asio::const_buffer &get(void) const{
+        return _buff;
+    }
+
+private:
+    boost::asio::const_buffer _buff;
+};
+
+/***********************************************************************
+ * UDP zero copy implementation class
+ *
+ * This is the portable zero copy implementation for systems
+ * where a faster, platform specific solution is not available.
+ *
+ * It uses boost asio udp sockets and the standard recv() class,
+ * and in-fact, is not actually doing a zero-copy implementation.
+ **********************************************************************/
+class udp_zero_copy_impl : public udp_zero_copy{
+public:
+    //structors
+    udp_zero_copy_impl(const std::string &addr, const std::string &port);
+    ~udp_zero_copy_impl(void);
+
+    //send/recv
+    size_t send(const boost::asio::const_buffer &buff);
+    smart_buffer::sptr recv(void);
+
+private:
+    boost::asio::ip::udp::socket   *_socket;
+    boost::asio::io_service        _io_service;
+
+    size_t get_recv_buff_size(void);
+    void set_recv_buff_size(size_t);
+};
+
+udp_zero_copy_impl::udp_zero_copy_impl(const std::string &addr, const std::string &port){
+    //std::cout << boost::format("Creating udp transport for %s %s") % addr % port << std::endl;
+
+    // resolve the address
+    boost::asio::ip::udp::resolver resolver(_io_service);
+    boost::asio::ip::udp::resolver::query query(boost::asio::ip::udp::v4(), addr, port);
+    boost::asio::ip::udp::endpoint receiver_endpoint = *resolver.resolve(query);
+
+    // Create, open, and connect the socket
+    _socket = new boost::asio::ip::udp::socket(_io_service);
+    _socket->open(boost::asio::ip::udp::v4());
+    _socket->connect(receiver_endpoint);
+
+    // set the rx socket buffer size:
+    // pick a huge size, and deal with whatever we get
+    set_recv_buff_size(size_t(54321e3)); //some big number!
+    size_t current_buff_size = get_recv_buff_size();
+    std::cout << boost::format(
+        "Current rx socket buffer size: %d\n"
+    ) % current_buff_size;
+    if (current_buff_size < size_t(.1e6)) std::cout << boost::format(
+        "Adjust max rx socket buffer size (linux only):\n"
+        "  sysctl -w net.core.rmem_max=VALUE\n"
+    );
+}
+
+udp_zero_copy_impl::~udp_zero_copy_impl(void){
+    delete _socket;
+}
+
+size_t udp_zero_copy_impl::send(const boost::asio::const_buffer &buff){
+    return _socket->send(boost::asio::buffer(buff));
+}
+
+smart_buffer::sptr udp_zero_copy_impl::recv(void){
+    size_t available = 0;
+
+    //implement timeout through polling and sleeping
+    boost::asio::deadline_timer timer(_socket->get_io_service());
+    timer.expires_from_now(boost::posix_time::milliseconds(50));
+    while (not ((available = _socket->available()) or timer.expires_from_now().is_negative())){
+        boost::this_thread::sleep(boost::posix_time::milliseconds(1));
+    }
+
+    //allocate memory and create buffer
+    boost::uint32_t *buff_mem = new boost::uint32_t[available/sizeof(boost::uint32_t)];
+    boost::asio::mutable_buffer buff(buff_mem, available);
+
+    //receive only if data is available
+    if (available){
+        _socket->receive(boost::asio::buffer(buff));
+    }
+
+    //create a new smart buffer to house the data
+    return smart_buffer::sptr(new smart_buffer_impl(buff));
+}
+
+size_t udp_zero_copy_impl::get_recv_buff_size(void){
+    boost::asio::socket_base::receive_buffer_size option;
+    _socket->get_option(option);
+    return option.value();
+}
+
+void udp_zero_copy_impl::set_recv_buff_size(size_t new_size){
+    boost::asio::socket_base::receive_buffer_size option(new_size);
+    _socket->set_option(option);
+}
+
+/***********************************************************************
+ * UDP zero copy make function
+ **********************************************************************/
+udp_zero_copy::sptr udp_zero_copy::make(
+    const std::string &addr, const std::string &port
+){
+    return sptr(new udp_zero_copy_impl(addr, port));
+}