Flakeify

.gitignore

@@ -10,3 +10,5 @@ build/
 .zed
 .cache
 compile_commands.json
+
+install/

README.md

@@ -1,3 +1,77 @@
+# Cyclone DDS Fork
+
+These are my experiments with what exists in this repo, I added a `flake.nix` file which provides a `devShell` for building
+and running the `HelloworldPublisher/Subsriber` examples and got those working.
+
+Build this thing manually...
+
+For the DCMAKE_INSTALL_PREFIX, just create an install directory somewhere in the project, or under /tmp
+
+```
+mkdir -p build install  && cd build
+cmake -DCMAKE_INSTALL_PREFIX=../install -DBUILD_EXAMPLES=ON ..
+cmake --build . --parallel
+```
+
+After a successful build, you can specify the "install" location:
+
+```
+cmake --build . --target install
+```
+
+That'll kick out all the build artifacts:
+
+```
+17:24:40 (install) $ ll
+total 16K
+drwxr-xr-x 2 trey users 4.0K Dec 16 17:24 bin
+drwxr-xr-x 7 trey users 4.0K Dec 16 17:24 include
+drwxr-xr-x 3 trey users 4.0K Dec 16 17:24 share
+drwxr-xr-x 4 trey users 4.0K Dec 16 17:24 lib64
+```
+
+Note that the build/bin/ dir will have a bunch of extra executables, including the HelloWorld example:
+
+```
+17:28:07 (bin) $ pwd
+/home/trey/sources/cyclonedds/build/bin
+
+17:28:14 (bin) $ ll
+total 1.6M
+-rwxr-xr-x 1 trey users  38K Dec 16 17:22 dyntype
+-rwxr-xr-x 1 trey users  29K Dec 16 17:22 listtopics
+-rwxr-xr-x 1 trey users 290K Dec 16 17:22 symbol_export_test
+-rwxr-xr-x 1 trey users 194K Dec 16 17:22 dynsub
+-rwxr-xr-x 1 trey users 538K Dec 16 17:22 idlc
+-rwxr-xr-x 1 trey users  27K Dec 16 17:22 HelloworldPublisher
+-rwxr-xr-x 1 trey users  43K Dec 16 17:22 variouspub
+-rwxr-xr-x 1 trey users  37K Dec 16 17:22 RoundtripPong
+-rwxr-xr-x 1 trey users  38K Dec 16 17:22 ThroughputPublisher
+-rwxr-xr-x 1 trey users  28K Dec 16 17:22 HelloworldSubscriber
+-rwxr-xr-x 1 trey users  46K Dec 16 17:22 ThroughputSubscriber
+-rwxr-xr-x 1 trey users  57K Dec 16 17:22 RoundtripPing
+-rwxr-xr-x 1 trey users 246K Dec 16 17:22 ddsperf
+```
+
+On first go at the HelloworldPublisher and HelloworldSubscriber nothing worked,
+both executables just hung waiting with no extra logs.
+
+Providing this XML string as a configuration through the CYCLONEDDS_URI environment variable solved the problem,
+so the default behavior of auto-detecting the local network must just not be working. We got some log output
+claiming that NetworkInterfaceAddress is a deprecated element, but it seemed to accept this config, note this is done automatically in the `devShell` shipped in the flake.
+
+```
+export CYCLONEDDS_URI="<CycloneDDS><Domain><General><NetworkInterfaceAddress>127.0.0.1</NetworkInterfaceAddress></General></Domain></CycloneDDS>"
+```
+
+To provide a 
+
+```
+export CYCLONEDDS_URI="file://$HOME/CycloneDDS/my-config.xml"
+```
+
+---
+
 ![GitHub release](https://img.shields.io/github/v/release/eclipse-cyclonedds/cyclonedds?include_prereleases)
 [![Build Status](https://dev.azure.com/eclipse-cyclonedds/cyclonedds/_apis/build/status/Pull%20requests?branchName=master)](https://dev.azure.com/eclipse-cyclonedds/cyclonedds/_build/latest?definitionId=4&branchName=master)
 [![Coverity Status](https://scan.coverity.com/projects/19078/badge.svg)](https://scan.coverity.com/projects/eclipse-cyclonedds-cyclonedds)

flake.nix

@@ -0,0 +1,38 @@
+{
+  description = "Cyclone DDS";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
+  };
+
+  outputs = { self, nixpkgs }:
+    let
+      systems = [ "x86_64-linux" ];
+      forAllSystems = nixpkgs.lib.genAttrs systems;
+    in
+    {
+      devShells = forAllSystems (system:
+        let
+          pkgs = import nixpkgs { inherit system; };
+        in
+        {
+          default = pkgs.mkShell {
+            buildInputs = with pkgs; [
+              gcc
+              cmake
+              git
+              openssl
+            ];
+
+            shellHook = ''
+              echo "exporting a CYCLONEDDS_URI config with loopback NetworkInterfaceAddress"
+              export CYCLONEDDS_URI="<CycloneDDS><Domain><General><NetworkInterfaceAddress>127.0.0.1</NetworkInterfaceAddress></General></Domain></CycloneDDS>"
+            '';
+          };
+        });
+
+        # TODO: add a nix formatter...
+    };
+}
+
+

hello-world-config.xml

@@ -0,0 +1,25 @@
+<!-- This is an untested example DDS config I pulled off the Eclipse docs -->
+
+<?xml version="1.0" encoding="utf-8"?>
+<CycloneDDS
+  xmlns="https://cdds.io/config"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="https://cdds.io/config https://raw.githubusercontent.com/eclipse-cyclonedds/cyclonedds/master/etc/cyclonedds.xsd"
+>
+  <Domain Id="any">
+    <General>
+      <Interfaces>
+        <NetworkInterface autodetermine="true" priority="default"
+        multicast="default" />
+      </Interfaces>
+      <AllowMulticast>default</AllowMulticast>
+      <MaxMessageSize>65500B</MaxMessageSize>
+    </General>
+    <Tracing>
+      <Verbosity>config</Verbosity>
+      <OutputFile>
+        ${HOME}/dds/log/cdds.log.${CYCLONEDDS_PID}
+      </OutputFile>
+    </Tracing>
+  </Domain>
+</CycloneDDS>