From 202c69ad77bcf9c02969a52ea221b0e5f8478937 Mon Sep 17 00:00:00 2001
From: Erik Hofman <erik@ehofman.com>
Date: Tue, 6 Apr 2021 14:52:37 +0200
Subject: [PATCH] Implement the start of a property server using DDS.
---
src/Network/CMakeLists.txt | 7 +-
src/Network/DDS/CMakeLists.txt | 2 +
src/Network/DDS/dds_fwd.hxx | 10 ++
src/Network/DDS/dds_props.c | 46 +++++++++
src/Network/DDS/dds_props.h | 75 +++++++++++++++
src/Network/DDS/dds_props.idl | 85 +++++++++++++++++
src/Network/dds_props.cxx | 167 +++++++++++++++++++++++++++++++++
src/Network/dds_props.hxx | 57 +++++++++++
8 files changed, 448 insertions(+), 1 deletion(-)
create mode 100644 src/Network/DDS/dds_fwd.hxx
create mode 100644 src/Network/DDS/dds_props.c
create mode 100644 src/Network/DDS/dds_props.h
create mode 100644 src/Network/DDS/dds_props.idl
create mode 100644 src/Network/dds_props.cxx
create mode 100644 src/Network/dds_props.hxx
diff --git a/src/Network/CMakeLists.txt b/src/Network/CMakeLists.txt
index 274dd739a..e16e3ddf5 100644
--- a/src/Network/CMakeLists.txt
+++ b/src/Network/CMakeLists.txt
@@ -62,11 +62,16 @@ set(HEADERS
rul.hxx
)
+if (CycloneDDS_FOUND)
+ set(SOURCES ${SOURCES} dds_props.cxx)
+ set(HEADERS ${HEADERS} dds_props.hxx)
+endif()
+
if(ENABLE_IAX)
list(APPEND SOURCES fgcom.cxx)
list(APPEND HEADERS fgcom.hxx)
endif()
-
+
flightgear_component(Network "${SOURCES}" "${HEADERS}")
if (CycloneDDS_FOUND)
diff --git a/src/Network/DDS/CMakeLists.txt b/src/Network/DDS/CMakeLists.txt
index 8372f6d73..b96b64e60 100644
--- a/src/Network/DDS/CMakeLists.txt
+++ b/src/Network/DDS/CMakeLists.txt
@@ -4,12 +4,14 @@ set(SOURCES
dds_ctrls.c
dds_gui.c
dds_fdm.c
+ dds_props.c
)
set(HEADERS
dds_ctrls.h
dds_fdm.h
dds_gui.h
+ dds_props.h
)
add_executable(fg_dds_log
diff --git a/src/Network/DDS/dds_fwd.hxx b/src/Network/DDS/dds_fwd.hxx
new file mode 100644
index 000000000..ddbe9f44e
--- /dev/null
+++ b/src/Network/DDS/dds_fwd.hxx
@@ -0,0 +1,10 @@
+// dds_fwd.hxx
+//
+// This file is in the Public Domain, and comes with no warranty.
+
+#pragma once
+
+#include "dds_gui.h"
+#include "dds_fdm.h"
+#include "dds_ctrls.h"
+
diff --git a/src/Network/DDS/dds_props.c b/src/Network/DDS/dds_props.c
new file mode 100644
index 000000000..79ef5628d
--- /dev/null
+++ b/src/Network/DDS/dds_props.c
@@ -0,0 +1,46 @@
+/****************************************************************
+
+ Generated by Eclipse Cyclone DDS IDL to C Translator
+ File name: dds_props.c
+ Source: dds_props.idl
+ Cyclone DDS: V0.7.0
+
+*****************************************************************/
+#include "dds_props.h"
+
+
+static const dds_key_descriptor_t FG_DDS_PROP_keys[1] =
+{
+ { "id", 0 }
+};
+
+static const uint32_t FG_DDS_PROP_ops [] =
+{
+ DDS_OP_ADR | DDS_OP_TYPE_4BY | DDS_OP_FLAG_SGN | DDS_OP_FLAG_KEY, offsetof (FG_DDS_PROP, id),
+ DDS_OP_ADR | DDS_OP_TYPE_4BY | DDS_OP_FLAG_SGN, offsetof (FG_DDS_PROP, type),
+ DDS_OP_ADR | DDS_OP_TYPE_UNI | DDS_OP_SUBTYPE_4BY | DDS_OP_FLAG_SGN, offsetof (FG_DDS_PROP, val._d), 9u, (31u << 16) + 4u,
+ DDS_OP_JEQ | DDS_OP_TYPE_BOO | 0, FG_DDS_BOOL, offsetof (FG_DDS_PROP, val._u.Bool),
+ DDS_OP_JEQ | DDS_OP_TYPE_4BY | DDS_OP_FLAG_SGN | 0, FG_DDS_NONE, offsetof (FG_DDS_PROP, val._u.Int32),
+ DDS_OP_JEQ | DDS_OP_TYPE_4BY | DDS_OP_FLAG_SGN | 0, FG_DDS_INT, offsetof (FG_DDS_PROP, val._u.Int32),
+ DDS_OP_JEQ | DDS_OP_TYPE_8BY | DDS_OP_FLAG_SGN | 0, FG_DDS_LONG, offsetof (FG_DDS_PROP, val._u.Int64),
+ DDS_OP_JEQ | DDS_OP_TYPE_4BY | DDS_OP_FLAG_FP | 0, FG_DDS_FLOAT, offsetof (FG_DDS_PROP, val._u.Float32),
+ DDS_OP_JEQ | DDS_OP_TYPE_8BY | DDS_OP_FLAG_FP | 0, FG_DDS_DOUBLE, offsetof (FG_DDS_PROP, val._u.Float64),
+ DDS_OP_JEQ | DDS_OP_TYPE_STR | 0, FG_DDS_ALIAS, offsetof (FG_DDS_PROP, val._u.String),
+ DDS_OP_JEQ | DDS_OP_TYPE_STR | 0, FG_DDS_STRING, offsetof (FG_DDS_PROP, val._u.String),
+ DDS_OP_JEQ | DDS_OP_TYPE_STR | 0, FG_DDS_UNSPECIFIED, offsetof (FG_DDS_PROP, val._u.String),
+ DDS_OP_ADR | DDS_OP_TYPE_STR, offsetof (FG_DDS_PROP, guid),
+ DDS_OP_RTS
+};
+
+const dds_topic_descriptor_t FG_DDS_PROP_desc =
+{
+ sizeof (FG_DDS_PROP),
+ 8u,
+ DDS_TOPIC_FIXED_KEY | DDS_TOPIC_NO_OPTIMIZE | DDS_TOPIC_CONTAINS_UNION,
+ 1u,
+ "FG::DDS_PROP",
+ FG_DDS_PROP_keys,
+ 14,
+ FG_DDS_PROP_ops,
+ "<MetaData version=\"1.0.0\"><Module name=\"FG\"><Enum name=\"propType\"><Element name=\"DDS_NONE\" value=\"0\"/><Element name=\"DDS_ALIAS\" value=\"1\"/><Element name=\"DDS_BOOL\" value=\"2\"/><Element name=\"DDS_INT\" value=\"3\"/><Element name=\"DDS_LONG\" value=\"4\"/><Element name=\"DDS_FLOAT\" value=\"5\"/><Element name=\"DDS_DOUBLE\" value=\"6\"/><Element name=\"DDS_STRING\" value=\"7\"/><Element name=\"DDS_UNSPECIFIED\" value=\"8\"/></Enum><Union name=\"propValue\"><SwitchType><Type name=\"propType\"/></SwitchType><Case name=\"Bool\"><Boolean/><Label value=\"DDS_BOOL\"/></Case><Case name=\"Int32\"><Long/><Label value=\"DDS_NONE\"/><Label value=\"DDS_INT\"/></Case><Case name=\"Int64\"><LongLong/><Label value=\"DDS_LONG\"/></Case><Case name=\"Float32\"><Float/><Label value=\"DDS_FLOAT\"/></Case><Case name=\"Float64\"><Double/><Label value=\"DDS_DOUBLE\"/></Case><Case name=\"String\"><String/><Label value=\"DDS_ALIAS\"/><Label value=\"DDS_STRING\"/><Label value=\"DDS_UNSPECIFIED\"/></Case></Union><Struct name=\"DDS_PROP\"><Member name=\"id\"><Long/></Member><Member name=\"type\"><Type name=\"propType\"/></Member><Member name=\"val\"><Type name=\"propValue\"/></Member><Member name=\"guid\"><String/></Member></Struct></Module></MetaData>"
+};
diff --git a/src/Network/DDS/dds_props.h b/src/Network/DDS/dds_props.h
new file mode 100644
index 000000000..eab4fa324
--- /dev/null
+++ b/src/Network/DDS/dds_props.h
@@ -0,0 +1,75 @@
+/****************************************************************
+
+ Generated by Eclipse Cyclone DDS IDL to C Translator
+ File name: dds_props.h
+ Source: dds_props.idl
+ Cyclone DDS: V0.7.0
+
+*****************************************************************/
+
+#include "dds/ddsc/dds_public_impl.h"
+
+#ifndef _DDSL_DDS_PROPS_H_
+#define _DDSL_DDS_PROPS_H_
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define FG_DDS_PROP_REQUEST -1
+typedef enum FG_propType
+{
+ FG_DDS_NONE,
+ FG_DDS_ALIAS,
+ FG_DDS_BOOL,
+ FG_DDS_INT,
+ FG_DDS_LONG,
+ FG_DDS_FLOAT,
+ FG_DDS_DOUBLE,
+ FG_DDS_STRING,
+ FG_DDS_UNSPECIFIED
+} FG_propType;
+
+#define FG_propType__alloc() \
+((FG_propType*) dds_alloc (sizeof (FG_propType)));
+
+
+typedef struct FG_propValue
+{
+ FG_propType _d;
+ union
+ {
+ bool Bool;
+ int32_t Int32;
+ int64_t Int64;
+ float Float32;
+ double Float64;
+ char * String;
+ } _u;
+} FG_propValue;
+
+#define FG_propValue__alloc() \
+((FG_propValue*) dds_alloc (sizeof (FG_propValue)));
+
+
+typedef struct FG_DDS_PROP
+{
+ int32_t id;
+ FG_propType type;
+ FG_propValue val;
+ char * guid;
+} FG_DDS_PROP;
+
+extern const dds_topic_descriptor_t FG_DDS_PROP_desc;
+
+#define FG_DDS_PROP__alloc() \
+((FG_DDS_PROP*) dds_alloc (sizeof (FG_DDS_PROP)));
+
+#define FG_DDS_PROP_free(d,o) \
+dds_sample_free ((d), &FG_DDS_PROP_desc, (o))
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* _DDSL_DDS_PROPS_H_ */
diff --git a/src/Network/DDS/dds_props.idl b/src/Network/DDS/dds_props.idl
new file mode 100644
index 000000000..02716fd93
--- /dev/null
+++ b/src/Network/DDS/dds_props.idl
@@ -0,0 +1,85 @@
+// format dfescription: https://www.omg.org/spec/IDL/4.2/PDF
+
+// Adapted from net_fdm.hxx
+module FG
+{
+
+// defining it this way also generates accompanying #defines in the header file.
+const short DDS_PROP_REQUEST = -1;
+
+enum propType
+{
+ DDS_NONE, // The node hasn't been assigned a value yet
+ DDS_ALIAS, // The node "points" to another node
+ DDS_BOOL,
+ DDS_INT, // 32-bit integer
+ DDS_LONG, // 64-bit integer
+ DDS_FLOAT, // 32-bit floating point number
+ DDS_DOUBLE, // 64-bit floating point number
+ DDS_STRING, // UTF-8 string
+ DDS_UNSPECIFIED // Resolves to STRING
+};
+
+union propValue switch ( propType )
+{
+ case DDS_BOOL:
+ boolean Bool;
+
+ case DDS_NONE:
+ case DDS_INT:
+ long Int32;
+
+ case DDS_LONG:
+ long long Int64;
+
+ case DDS_FLOAT:
+ float Float32;
+
+ case DDS_DOUBLE:
+ double Float64;
+
+ case DDS_ALIAS:
+ case DDS_STRING:
+ case DDS_UNSPECIFIED:
+ string String;
+};
+
+// Initial property request sequence
+// for properties where the id is not yet known:
+// 1. Set id to FG_DDS_PROP_REQUEST
+// 2. set guid to the 16-byte participants GUID
+// 3. Set type to STRING
+// 4. Set val.String to the propery path
+// 5. Send the package.
+//
+// 6. wait for an answer
+// * Check whether guid matches the participants GUID.
+// * The index of the requested propery path is stored in the id variable
+// which should be used by successive request as the id for that property.
+// * The type variable indicates the type of the value of the property.
+// * The val union holds the value of the propery.
+//
+// Successive property request sequence:
+// 1. Set id to the id of the requested property
+// 2. Send the package.
+//
+// 3. wait for an answer
+// * Check whether id matches the requested property id.
+// * The type variable indicates the type of the value of the property.
+// * The val union holds the value of the propery.
+//
+// guid is not defined as an array of 16 unsigned characters to keep the
+// sample small for successive requests. This way only a FG_DDS_PROP_REQUEST
+// sample will reserve the full 16-bytes.
+struct DDS_PROP
+{
+ long id; // property index and DDS id
+
+ propType type;
+ propValue val;
+
+ string guid; // requesters globally unique identifier
+};
+#pragma keylist DDS_PROP id
+
+}; // module FG
diff --git a/src/Network/dds_props.cxx b/src/Network/dds_props.cxx
new file mode 100644
index 000000000..62ce7fa68
--- /dev/null
+++ b/src/Network/dds_props.cxx
@@ -0,0 +1,167 @@
+// dds_props.cxx -- FGFS "DDS" properties protocal class
+//
+// Written by Erik Hofman, started April 2021
+//
+// Copyright (C) 2021 by Erik Hofman <erik@ehofman.com>
+//
+// 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+//
+// $Id$
+
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <simgear/debug/logstream.hxx>
+#include <simgear/io/iochannel.hxx>
+#include <simgear/props/props.hxx>
+
+#include <simgear/io/SGDataDistributionService.hxx>
+
+#include <Main/fg_props.hxx>
+#include <Main/globals.hxx>
+
+#include "dds_props.hxx"
+
+// open hailing frequencies
+bool FGDDSProps::open() {
+ if (is_enabled()) {
+ SG_LOG(SG_IO, SG_ALERT, "This shouldn't happen, but the channel "
+ << "is already in use, ignoring");
+ return false;
+ }
+
+ SGIOChannel *io = get_io_channel();
+
+ SG_DDS_Topic *dds = static_cast<SG_DDS_Topic*>(io);
+ dds->setup<FG_DDS_PROP>(&FG_DDS_PROP_desc);
+
+ // always send and recieve.
+ if (! io->open(SG_IO_BI)) {
+ SG_LOG(SG_IO, SG_ALERT, "Error opening channel communication layer.");
+ return false;
+ }
+
+ set_enabled(true);
+
+ return true;
+}
+
+// process work for this port
+bool FGDDSProps::process() {
+ SGIOChannel *io = get_io_channel();
+ FG_DDS_PROP prop;
+
+ int length = sizeof(prop);
+ char *buf = reinterpret_cast<char*>(&prop);
+
+ if (get_direction() == SG_IO_IN)
+ {
+ // act as a client: send a request and wait for an answer.
+
+ }
+ else if (get_direction() == SG_IO_OUT)
+ {
+ // act as a server: read requests and send the results.
+ while (io->read(buf, length) == length)
+ {
+ if (prop.id == FG_DDS_PROP_REQUEST)
+ {
+ auto it = by_path.find(prop.val._u.String);
+ if (it == by_path.end())
+ {
+ SGPropertyNode_ptr props = globals->get_props();
+ SGPropertyNode_ptr p = props->getNode(prop.val._u.String);
+ if (p)
+ {
+ prop.id = by_id.size();
+ by_id[prop.id] = p;
+ by_path[prop.val._u.String] = p;
+ }
+ setProp(prop, p);
+ }
+ else
+ {
+ prop.id = std::distance(by_path.begin(), it);
+ setProp(prop, it->second);
+ }
+ }
+ else
+ {
+ SGPropertyNode_ptr p = by_id[prop.id];
+ setProp(prop, p);
+ }
+
+ // send the response.
+ if (! io->write(buf, length)) {
+ SG_LOG(SG_IO, SG_ALERT, "Error writing data.");
+ }
+ } // while
+ }
+
+ return true;
+}
+
+// close the channel
+bool FGDDSProps::close() {
+ SGIOChannel *io = get_io_channel();
+
+ set_enabled(false);
+
+ if (! io->close()) {
+ return false;
+ }
+
+ return true;
+}
+
+void FGDDSProps::setProp(FG_DDS_PROP& prop, SGPropertyNode_ptr p)
+{
+ if (p)
+ {
+ simgear::props::Type type = p->getType();
+ if (type == simgear::props::BOOL) {
+ prop.type = FG_DDS_BOOL;
+ prop.val._u.Bool = p->getBoolValue();
+ } else if (type == simgear::props::INT) {
+ prop.type = FG_DDS_INT;
+ prop.val._u.Int32 = p->getIntValue();
+ } else if (type == simgear::props::LONG) {
+ prop.type = FG_DDS_LONG;
+ prop.val._u.Int64 = p->getLongValue();
+ } else if (type == simgear::props::FLOAT) {
+ prop.type = FG_DDS_FLOAT;
+ prop.val._u.Float32 = p->getFloatValue();
+ } else if (type == simgear::props::DOUBLE) {
+ prop.type = FG_DDS_DOUBLE;
+ prop.val._u.Float64 = p->getDoubleValue();
+ } else if (type == simgear::props::ALIAS) {
+ prop.type = FG_DDS_ALIAS;
+ prop.val._u.String = const_cast<char*>(p->getStringValue());
+ } else if (type == simgear::props::STRING) {
+ prop.type = FG_DDS_STRING;
+ prop.val._u.String = const_cast<char*>(p->getStringValue());
+ } else if (type == simgear::props::UNSPECIFIED) {
+ prop.type = FG_DDS_UNSPECIFIED;
+ prop.val._u.String = const_cast<char*>(p->getStringValue());
+ } else {
+ prop.type = FG_DDS_NONE;
+ prop.val._u.Int32 = 0;
+ }
+ }
+}
+
+
diff --git a/src/Network/dds_props.hxx b/src/Network/dds_props.hxx
new file mode 100644
index 000000000..0c874d1d0
--- /dev/null
+++ b/src/Network/dds_props.hxx
@@ -0,0 +1,57 @@
+// dds_props.hxx -- FGFS "DDS" properties protocal class
+//
+// Written by Erik Hofman, started April 2021
+//
+// Copyright (C) 2021 by Erik Hofman <erik@ehofman.com>
+//
+// 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+//
+// $Id$
+
+
+#pragma once
+
+#include <string>
+#include <map>
+
+#include <simgear/compiler.h>
+
+#include <simgear/props/propsfwd.hxx>
+
+#include "protocol.hxx"
+#include "DDS/dds_props.h"
+
+
+class FGDDSProps : public FGProtocol {
+
+ std::map<uint32_t,SGPropertyNode_ptr> by_id;
+ std::map<std::string,SGPropertyNode_ptr> by_path;
+
+ static void setProp(FG_DDS_PROP& prop, SGPropertyNode_ptr p);
+
+public:
+
+ FGDDSProps() = default;
+ ~FGDDSProps() = default;
+
+ // open hailing frequencies
+ bool open();
+
+ // process work for this port
+ bool process();
+
+ // close the channel
+ bool close();
+};