[examples]: Test the SLIP netif example on target as well

.github/workflows/examples_build-host-test.yml

@@ -13,12 +13,15 @@ jobs:
     name: Build examples
     strategy:
       matrix:
-        idf_ver: ["latest", "release-v5.1", "release-v5.2", "release-v5.3"]
+        idf_ver: ["latest", "release-v5.1", "release-v5.2", "release-v5.3", "release-v5.4"]
         include:
           - idf_ver: "latest"
             warning: "Warning: The smallest app partition is nearly full"
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}
+    env:
+      TARGET_TEST: examples/esp_netif/slip_custom_netif/
+      TARGET_TEST_DIR: build_esp32c3_target
     steps:
       - name: Checkout esp-protocols
         uses: actions/checkout@v4
@@ -31,6 +34,16 @@ jobs:
           python -m pip install idf-build-apps
           # Build default configs for all targets
           python ./ci/build_apps.py examples -m examples/.build-test-rules.yml -d -c
+          # Build target tests
+          python ./ci/build_apps.py ${TARGET_TEST} -r sdkconfig.ci=target
+          cd ${TARGET_TEST}
+          ${GITHUB_WORKSPACE}/ci/clean_build_artifacts.sh `pwd`/${TARGET_TEST_DIR}
+          zip -qur artifacts.zip ${TARGET_TEST_DIR}
+      - uses: actions/upload-artifact@v4
+        with:
+          name: slip_target_${{ matrix.idf_ver }}
+          path: ${{ env.TARGET_TEST }}/artifacts.zip
+          if-no-files-found: error
 
   build_and_run_on_host:
     if: contains(github.event.pull_request.labels.*.name, 'examples') || github.event_name == 'push'
@@ -51,3 +64,38 @@ jobs:
           python ./ci/build_apps.py examples/mqtt -l -t linux
           timeout 5 ./examples/mqtt/build_linux_default/esp_mqtt_demo.elf | tee test.log  || true
           grep 'MQTT_EVENT_DATA' test.log
+
+  run_on_target:
+    # Skip running on forks since it won't have access to secrets
+    if: |
+      github.repository == 'espressif/esp-protocols' &&
+      ( contains(github.event.pull_request.labels.*.name, 'examples') || github.event_name == 'push' )
+    name: Slip example target test
+    needs: build_all_examples
+    strategy:
+      matrix:
+        idf_ver: ["release-v5.4", "latest"]
+    runs-on:
+      - self-hosted
+      - modem
+    env:
+      TARGET_TEST: examples/esp_netif/slip_custom_netif/
+      TARGET_TEST_DIR: build_esp32c3_target
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/download-artifact@v4
+        with:
+          name: slip_target_${{ matrix.idf_ver }}
+          path: ${{ env.TARGET_TEST }}/ci/
+      - name: Run Test
+        working-directory: ${{ env.TARGET_TEST }}
+        run: |
+          python -m venv .venv
+          source .venv/bin/activate
+          pip install --prefer-binary cryptography pytest-embedded pytest-embedded-serial-esp pytest-embedded-idf pytest-custom_exit_code esptool netifaces
+          unzip ci/artifacts.zip -d ci
+          for dir in `ls -d ci/build_*`; do
+          rm -rf build sdkconfig.defaults
+          mv $dir build
+          python -m pytest --log-cli-level DEBUG --target=esp32c3
+          done

examples/esp_netif/slip_custom_netif/pytest_slip.py

@@ -0,0 +1,98 @@
+# SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: Unlicense OR CC0-1.0
+from __future__ import print_function, unicode_literals
+
+import subprocess
+import time
+from threading import Event, Thread
+
+import netifaces
+
+
+def is_esp32(port):
+    """
+    Check if the given port is connected to an ESP32 using esptool.
+    """
+    try:
+        result = subprocess.run(
+            ['esptool.py', '--port', port, 'chip_id'],
+            stdout=subprocess.PIPE, stderr=subprocess.PIPE, check=True, text=True
+        )
+        return 'ESP32' in result.stdout
+    except subprocess.CalledProcessError:
+        return False
+
+
+def run_server(server_stop, port):
+    print('Launching SLIP netif on port: {}'.format(port))
+    try:
+        arg_list = ['sudo', 'slattach', '-v', '-L', '-s', '115200','-p', 'slip', port]
+        p = subprocess.Popen(arg_list, stdout=subprocess.PIPE, bufsize=1)
+        while not server_stop.is_set():
+            if p.poll() is not None:
+                if p.poll() == 16:
+                    print('[SLIP:] Terminated: hang-up received')
+                    break
+                else:
+                    raise ValueError(
+                        'ENV_TEST_FAILURE: SLIP terminated unexpectedly with {}'
+                        .format(p.poll()))
+            time.sleep(0.1)
+    except Exception as e:
+        print(e)
+        raise ValueError('ENV_TEST_FAILURE: Error running SLIP netif')
+    finally:
+        p.terminate()
+    print('SLIP netif stopped')
+
+
+def test_examples_protocol_slip(dut):
+
+    # the PPP test env is reused for SLIP test and it uses three ttyUSB's: two for ESP32 board and another one for the ppp server
+    server_port = None
+    for i in ['/dev/ttyUSB0', '/dev/ttyUSB1', '/dev/ttyUSB2']:
+        if i == dut.serial.port:
+            print(f'DUT port: {i}')
+        elif is_esp32(i):
+            print(f'Some other ESP32: {i}')
+        else:
+            print(f'Port for SLIP: {i}')
+            server_port = i
+    if server_port is None:
+        print('ENV_TEST_FAILURE: Cannot locate SLIP port')
+        raise
+    # Attach to the SLI netif
+    server_stop = Event()
+    t = Thread(target=run_server, args=(server_stop, server_port))
+    t.start()
+    try:
+        # Setups the SLIP interface
+        ppp_server_timeout = time.time() + 30
+        while 'sl0' not in netifaces.interfaces():
+            print(
+                "SLIP netif hasn't appear yet, list of active netifs:{}"
+                .format(netifaces.interfaces()))
+            time.sleep(0.5)
+            if time.time() > ppp_server_timeout:
+                raise ValueError(
+                    'ENV_TEST_FAILURE: SLIP netif failed to setup sl0 interface within timeout'
+                )
+        # Configure the SLIP interface with IP addresses of both ends
+        cmd = ['sudo', 'ifconfig', 'sl0', '10.0.0.1', 'dstaddr', '10.0.0.2']
+        try:
+            subprocess.run(cmd, check=True)
+            print('SLIP interface configured successfully.')
+        except subprocess.CalledProcessError as e:
+            print(f'Failed to configure SLIP interface: {e}')
+        # Ping the SLIP interface with 5 packets and 10 seconds timeout
+        cmd = ['ping', '10.0.0.2', '-c', '5', '-W', '10']
+        try:
+            subprocess.run(cmd, check=True)
+            print('Pinging SLIP interface successfully.')
+        except subprocess.CalledProcessError as e:
+            print(f'Failed to ping SLIP interface: {e}')
+            raise
+
+    finally:
+        server_stop.set()
+        t.join()

examples/esp_netif/slip_custom_netif/sdkconfig.ci

@@ -0,0 +1,6 @@
+CONFIG_IDF_TARGET="esp32c3"
+CONFIG_LWIP_PPP_SUPPORT=y
+CONFIG_LWIP_SLIP_SUPPORT=y
+CONFIG_EXAMPLE_IPV4=y
+CONFIG_EXAMPLE_UART_TX_PIN=6
+CONFIG_EXAMPLE_UART_RX_PIN=7

examples/esp_netif/slip_custom_netif/sdkconfig.defaults

@@ -1,2 +1,5 @@
 # Override some defaults to enable SLIP
 CONFIG_LWIP_SLIP_SUPPORT=y
+# Workaround: Enable PPP to let esp_netif know that lwip's netif->state
+#             will be occupied (by SLIP netif info)
+CONFIG_LWIP_PPP_SUPPORT=y