scripts: net: Add script for running sample tests

Add a script that sets up Docker networking and starts the net-tools
Docker container. If successful, run Zephyr with native_posix and
execute the appropriate net-tools container executable. The proper
net-tools executable and arguments is selected depending on the
basename of the sample directory. This script needs to be updated
if the net-tools Docker image is updated in some incompatible way.

The net-tools directory is assumed to exist at the same level as
the Zephyr base directory, but its location can be set using the
'-N' command line argument. Likewise, '-Z' sets the Zephyr top level
directory.

When stopping Zephyr, go through all child processes since running a
native posix or other variant of Zephyr may cause a hierarchy of
processes to be created.

Fixes: #19540

Signed-off-by: Patrik Flykt <[email protected]>

CODEOWNERS

@@ -344,6 +344,7 @@
 /scripts/gen_kobject_list.py              @andrewboie
 /scripts/gen_priv_stacks.py               @andrewboie @agross-oss @ioannisg
 /scripts/gen_syscalls.py                  @andrewboie
+/scripts/net/                             @jukkar @pfl
 /scripts/process_gperf.py                 @andrewboie
 /scripts/gen_relocate_app.py              @wentongwu
 /scripts/sanity_chk/                      @nashif

scripts/net/README.txt

@@ -0,0 +1,64 @@
+The shell script run-sample-tests.sh runs a few Zephyr samples against the
+network test applications container provided by the 'net-tools'
+Zephyr project, https://github.com/zephyrproject-rtos/net-tools.
+
+
+Installation
+************
+
+As a prerequisite it is assumed that Docker is installed and that the
+'net-tools' Docker container has been created, see the first bullet point
+at the net-tools Docker README file
+https://github.com/zephyrproject-rtos/net-tools/blob/master/README.docker.
+In essence, the following needs to be done:
+
+ * Install Docker
+ * Check out the net-tools project from github or update it with west
+ * Change working directory to the net-tools repository
+ * Run './net-setup.sh --config docker.conf'
+
+This runs a Docker image called 'net-tools' and sets up docker network
+'net-tools0' on your local machine.
+
+
+Using
+*****
+
+The scripts/net/run-sample-tests.sh shell script is meant to be run from the
+relevant Zephyr network sample test directory. Currently the following two
+samples are supported:
+
+ * samples/net/sockets/echo_client
+ * samples/net/sockets/echo_server
+
+The applications to run in the net-tools Docker container are selected based
+on the name of the sample directory, for echo_client the echo_server
+application is started from the Docker container, and with echo_server
+echo_client is started in the Docker container. When completed, the return
+value, either from Zephyr or from the Docker container, is returned to the
+script on Zephyr or Docker application termination. The return value is used
+as a simple verdict whether the sample passed or failed.
+
+The Docker container and a corresponding 'net-tools0' Docker network is started
+by the script, as well as Zephyr using native_posix. IP addresses are assigned
+to the Docker network, which is a Linux network bridge interface. The IP
+addresses are set based on the sample being run.
+
+ * echo_client uses addresses 192.0.2.1 and 2001:db8::1
+ * echo_server uses addresses 192.0.2.2 and 2001:db8::2
+ * the Docker bridge interface uses addresses 192.0.2.254 and 2001:db8::254
+
+
+Directories
+***********
+
+The sample test script tries to automatically figure out the Zephyr base
+directory, which is assumed to be set by the ZEPHYR_BASE environment variable.
+Should this not be the case, the directory can be set using '-Z' or
+'--zephyr-dir' command line arguments. The sample test script also assumes
+that the net-tools git repository containing the Docker networking setup file
+'docker.conf' exists at the same directory level as the Zephyr base directory.
+If the net tools are found elsewhere, the net-tools directory can be set with
+the 'N' or '--net-tools-dir' command line argument.
+
+Help is also available using the 'h' or '--help' argument.