support/testing: add libcurl runtime test

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit 292631cd090fb3453c02926b77d6361dd965c112)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

DEVELOPERS

@@ -1799,6 +1799,7 @@ F:	support/testing/tests/package/test_kmscube/
 F:	support/testing/tests/package/test_less.py
 F:	support/testing/tests/package/test_libcamera.py
 F:	support/testing/tests/package/test_libcamera/
+F:	support/testing/tests/package/test_libcurl.py
 F:	support/testing/tests/package/test_libgpgme.py
 F:	support/testing/tests/package/test_libjxl.py
 F:	support/testing/tests/package/test_links.py

support/testing/tests/package/test_libcurl.py

@@ -0,0 +1,55 @@
+import os
+
+import infra.basetest
+
+
+class TestLibCurl(infra.basetest.BRTest):
+    config = infra.basetest.BASIC_TOOLCHAIN_CONFIG + \
+        """
+        BR2_PACKAGE_LIBCURL=y
+        BR2_PACKAGE_LIBCURL_CURL=y
+        BR2_PACKAGE_THTTPD=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
+        """
+
+    def test_run(self):
+        cpio_file = os.path.join(self.builddir, "images", "rootfs.cpio")
+        self.emulator.boot(arch="armv5",
+                           kernel="builtin",
+                           options=["-initrd", cpio_file])
+        self.emulator.login()
+
+        msg = "Hello Buildroot!"
+        fname = "file.txt"
+        url = f"http://localhost/{fname}"
+
+        # We check the program can execute.
+        self.assertRunOk("curl --version")
+
+        # We create a simple file to serve.
+        self.assertRunOk(f"echo '{msg}' > /var/www/data/{fname}")
+
+        # We try to download that file, using our local httpd server.
+        self.assertRunOk(f"curl -o {fname} {url}")
+
+        # We check the downloaded file contains our initial message.
+        out, ret = self.emulator.run(f"cat {fname}")
+        self.assertEqual(ret, 0)
+        self.assertEqual(out[0], msg)
+
+        # We download again the file without saving it, but printing
+        # it on stdout this time.
+        out, ret = self.emulator.run(f"curl -q {url}")
+        self.assertEqual(ret, 0)
+        self.assertEqual(out[0], msg)
+
+        # We download one last time, showing the server response. We
+        # check we can see the OK status and our thttpd server
+        # identification.
+        cmd = f"curl --no-progress-meter --dump-header - -o /dev/null {url}"
+        out, ret = self.emulator.run(cmd)
+        self.assertEqual(ret, 0)
+        out_str = "\n".join(out)
+        self.assertIn("HTTP/1.1 200 OK", out_str)
+        self.assertIn("Server: thttpd/", out_str)