support/testing: add attr runtime test

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>
(cherry picked from commit 2da40a2fd7a0007ff1a51bc957980f516746a6ad)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

DEVELOPERS

@@ -1763,6 +1763,7 @@ F:	support/testing/tests/package/test_acl.py
 F:	support/testing/tests/package/test_acpica.py
 F:	support/testing/tests/package/test_acpica/
 F:	support/testing/tests/package/test_apache.py
+F:	support/testing/tests/package/test_attr.py
 F:	support/testing/tests/package/test_bc.py
 F:	support/testing/tests/package/test_bitcoin.py
 F:	support/testing/tests/package/test_brotli.py

support/testing/tests/package/test_attr.py

@@ -0,0 +1,75 @@
+import os
+
+
+import infra.basetest
+
+
+class TestAttr(infra.basetest.BRTest):
+    # Note: this test uses extended attributes (xattr). We use a ext4
+    # rootfs (which fully supports xattrs). Note that tmpfs has
+    # partial support of xattrs, and cpio initrd has not.
+    config = infra.basetest.BASIC_TOOLCHAIN_CONFIG + \
+        """
+        BR2_PACKAGE_ATTR=y
+        BR2_TARGET_ROOTFS_EXT2=y
+        BR2_TARGET_ROOTFS_EXT2_4=y
+        # BR2_TARGET_ROOTFS_TAR is not set
+        """
+
+    def test_run(self):
+        disk_file = os.path.join(self.builddir, "images", "rootfs.ext4")
+        self.emulator.boot(arch="armv5",
+                           kernel="builtin",
+                           kernel_cmdline=["rootwait", "root=/dev/sda"],
+                           options=["-drive", f"file={disk_file},if=scsi,format=raw"])
+        self.emulator.login()
+
+        # Check the programs can execute.
+        self.assertRunOk("getfattr --version")
+        self.assertRunOk("setfattr --version")
+
+        test_file = "/root/file.txt"
+        attr_name = "buildroot"
+        attr_value = "is-great"
+
+        # Create a test file.
+        self.assertRunOk(f"echo 'Hello Buildroot!' > {test_file}")
+
+        # Set an extended attribute.
+        cmd = f"setfattr -n user.{attr_name} -v {attr_value} {test_file}"
+        self.assertRunOk(cmd)
+
+        # Read back the attribute value. We add an extra "echo" to add
+        # a new line. getfattr --only-values prints raw attribute
+        # values and lack of a new line.
+        cmd = "getfattr"
+        cmd += f" -n user.{attr_name} --absolute-names --only-values"
+        cmd += f" {test_file} && echo"
+        out, ret = self.emulator.run(cmd)
+        self.assertEqual(ret, 0)
+        self.assertEqual(out[0], attr_value)
+
+        # We read back the attribute value again, but with the "attr"
+        # command this time.
+        cmd = f"attr -q -g {attr_name} {test_file} && echo"
+        out, ret = self.emulator.run(cmd)
+        self.assertEqual(ret, 0)
+        self.assertEqual(out[0], attr_value)
+
+        # List extended attributes with "attr", and check we see our
+        # test attribute.
+        cmd = f"attr -l {test_file}"
+        out, ret = self.emulator.run(cmd)
+        self.assertEqual(ret, 0)
+        self.assertIn(attr_name, "\n".join(out))
+
+        # Remove the test attribute with setfattr.
+        cmd = f"setfattr -x user.{attr_name} {test_file}"
+        self.assertRunOk(cmd)
+
+        # We check the test attribute is no longer listed by the attr
+        # command.
+        cmd = f"attr -l {test_file}"
+        out, ret = self.emulator.run(cmd)
+        self.assertEqual(ret, 0)
+        self.assertNotIn(attr_name, "\n".join(out))