rfnoc: Move graph_edge data structure to its own header, add to_string()

This structure represents information about a graph edge. Required by
detail::graph and rfnoc_graph.

graph_edge_t::to_string() will now provide a textual representation of
the edge.

2 files changed, 87 insertions, 0 deletions

diff --git a/host/include/uhd/rfnoc/CMakeLists.txt b/host/include/uhd/rfnoc/CMakeLists.txt
index 41826a9cb..a16fa7330 100644
--- a/host/include/uhd/rfnoc/CMakeLists.txt
+++ b/host/include/uhd/rfnoc/CMakeLists.txt
@@ -16,6 +16,7 @@ if(ENABLE_RFNOC)
         defaults.hpp
         dirtifier.hpp
         graph.hpp
+        graph_edge.hpp
         noc_block_make_args.hpp
         node_ctrl_base.hpp
         node_ctrl_base.ipp
diff --git a/host/include/uhd/rfnoc/graph_edge.hpp b/host/include/uhd/rfnoc/graph_edge.hpp
new file mode 100644
index 000000000..8ab33f2a7
--- /dev/null
+++ b/host/include/uhd/rfnoc/graph_edge.hpp
@@ -0,0 +1,86 @@
+//
+// Copyright 2019 Ettus Research, a National Instruments Brand
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+
+#ifndef INCLUDED_LIBUHD_RFNOC_GRAPH_EDGE_HPP
+#define INCLUDED_LIBUHD_RFNOC_GRAPH_EDGE_HPP
+
+#include <uhd/config.hpp>
+#include <string>
+#include <tuple>
+
+namespace uhd { namespace rfnoc {
+
+/*! A container that holds information about a graph edge
+ *
+ * Note: The source and destination IDs are strings, not block IDs
+ * (uhd::rfnoc::block_id_t). This is because the graph can contain edges
+ * that are not between RFNoC blocks (e.g., to a streamer), and we need to
+ * be able to generically express node IDs.
+ */
+struct UHD_API graph_edge_t
+{
+    enum edge_t {
+        STATIC, ///< A static connection between two blocks in the FPGA
+        DYNAMIC, ///< A user (dynamic) connection between two blocks in the FPGA
+        RX_STREAM, ///< A connection from an FPGA block to a software RX streamer
+        TX_STREAM ///< A connection from a software TX streamer and an FPGA block
+    };
+
+    graph_edge_t() = default;
+
+    graph_edge_t(const size_t src_port_,
+        const size_t dst_port_,
+        const edge_t edge_,
+        const bool ppa)
+        : src_port(src_port_)
+        , dst_port(dst_port_)
+        , edge(edge_)
+        , property_propagation_active(ppa)
+    {
+    }
+
+    //! The ID of the source block for this edge
+    std::string src_blockid;
+    //! The port number of the source block for this edge
+    size_t src_port = 0;
+    //! The ID of the destination block for this edge
+    std::string dst_blockid;
+    //! The port number of the destination block for this edge
+    size_t dst_port = 0;
+    //! The type of edge
+    edge_t edge = DYNAMIC;
+    //! When true, the framework will use this edge for property propagation
+    bool property_propagation_active = true;
+
+    bool operator==(const graph_edge_t& rhs) const
+    {
+        return std::tie(src_blockid,
+                   src_port,
+                   dst_blockid,
+                   dst_port,
+                   edge,
+                   property_propagation_active)
+               == std::tie(rhs.src_blockid,
+                      rhs.src_port,
+                      rhs.dst_blockid,
+                      rhs.dst_port,
+                      rhs.edge,
+                      rhs.property_propagation_active);
+    }
+
+    //! Return a string representation of the connection
+    std::string to_string() const
+    {
+        return src_blockid + ":" + std::to_string(src_port)
+               + (edge == STATIC ? "==>" : "-->") + dst_blockid + ":"
+               + std::to_string(dst_port);
+    }
+};
+
+
+}} /* namespace uhd::rfnoc */
+
+#endif /* INCLUDED_LIBUHD_RFNOC_GRAPH_EDGE_HPP */