From e6b09edaca8578aec0a9108030af1d45f903994a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michael=20M=C3=BCller?= <michael.mueller@uos.de>
Date: Mon, 11 Jul 2022 11:57:05 +0200
Subject: [PATCH] Extended hello tutorial with second client and configurable
 parameters.

---
 repos/hello_tutorial/run/hello.run            |  7 +++
 repos/hello_tutorial/src/hello/client/main.cc | 52 ++++++++++++++++---
 2 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/repos/hello_tutorial/run/hello.run b/repos/hello_tutorial/run/hello.run
index f41fabc170..244550a19d 100644
--- a/repos/hello_tutorial/run/hello.run
+++ b/repos/hello_tutorial/run/hello.run
@@ -27,7 +27,14 @@ install_config {
 		<provides> <service name="Hello"/> </provides>
 	</start>
 	<start name="hello_client">
+		<binary name="hello_client"/>
 		<resource name="RAM" quantum="1M"/>
+		<config a="5" b="6"/>
+	</start>
+	<start name="hello_client2">
+		<binary name="hello_client"/>
+		<resource name="RAM" quantum="1M"/>
+		<config a="7" b="8"/>
 	</start>
 </config>}
 
diff --git a/repos/hello_tutorial/src/hello/client/main.cc b/repos/hello_tutorial/src/hello/client/main.cc
index 895c511e1f..eb4f12d569 100644
--- a/repos/hello_tutorial/src/hello/client/main.cc
+++ b/repos/hello_tutorial/src/hello/client/main.cc
@@ -14,17 +14,57 @@
 
 #include <base/component.h>
 #include <base/log.h>
+#include <base/attached_rom_dataspace.h>
 #include <hello_session/connection.h>
 
+struct HelloClient {
+	Genode::Env &_env;
+	Hello::Connection &_hello;
 
-void Component::construct(Genode::Env &env)
+	int _a;
+	int _b;
+
+	Genode::Attached_rom_dataspace _config{_env, "config"};
+
+
+	void _handle_config()
+	{
+		Genode::log("Reading config");
+		_config.update();
+
+		if (!_config.valid()) {
+			Genode::log("Config is invalid.");
+			return;
+		}
+
+		_a = _config.xml().attribute_value("a", 2);
+		_b = _config.xml().attribute_value("b", 5);	
+	}
+
+	Genode::Signal_handler<HelloClient> _config_handler {
+		_env.ep(), *this, &HelloClient::_handle_config
+	};
+
+	void run()
+	{
+		_hello.say_hello();
+
+		int const sum = _hello.add(_a, _b);
+		Genode::log("added ", _a, " + ", _b, " = ", sum);
+
+		Genode::log("hello test completed.");
+	}
+
+	HelloClient(Genode::Env &env, Hello::Connection &conn) : _env(env), _hello(conn)
+	{}
+};
+
+void
+Component::construct(Genode::Env &env)
 {
 	Hello::Connection hello(env);
 
-	hello.say_hello();
+	HelloClient client(env, hello);
+	client.run();
 
-	int const sum = hello.add(2, 5);
-	Genode::log("added 2 + 5 = ", sum);
-
-	Genode::log("hello test completed");
 }