fs: fat: add rename

The implementation roughly follows the POSIX specification for
rename() [1]. The ordering of operations attempting to minimize the chance
for data loss in unexpected circumstances.

The 'mv' command was implemented as a front end for the rename operation
as that is what most users are likely familiar with in terms of behavior.

The 'FAT_RENAME' Kconfig option was added to prevent code size increase on
size-oriented builds like SPL.

[1] https://pubs.opengroup.org/onlinepubs/9799919799/functions/rename.html

Signed-off-by: Gabriel Dalimonte <gabriel.dalimonte@gmail.com>

1 files changed, 372 insertions, 0 deletions

diff --git a/test/py/tests/test_fs/test_rename.py b/test/py/tests/test_fs/test_rename.py
new file mode 100644
index 00000000000..df2b2fd2945
--- /dev/null
+++ b/test/py/tests/test_fs/test_rename.py
@@ -0,0 +1,372 @@
+# SPDX-License-Identifier:      GPL-2.0+
+# Copyright 2025 Gabriel Dalimonte <gabriel.dalimonte@gmail.com>
+#
+# U-Boot File System:rename Test
+
+
+import pytest
+
+from fstest_defs import *
+from fstest_helpers import assert_fs_integrity
+
+@pytest.mark.boardspec('sandbox')
+@pytest.mark.slow
+class TestRename(object):
+    def test_rename1(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 1 - rename a file (successful mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 1 - rename a file'):
+            d = 'test1'
+            src = '%s/file1' % d
+            dst = '%s/file2' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s' % (ADDR, dst),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('file1' not in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test1'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename2(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 2 - rename a file to an existing file (successful mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 2 - rename a file to an existing file'):
+            d = 'test2'
+            src = '%s/file1' % d
+            dst = '%s/file_exist' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s' % (ADDR, dst),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('file1' not in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test2'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename3(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 3 - rename a directory (successful mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 3 - rename a directory'):
+            d = 'test3'
+            src = '%s/dir1' % d
+            dst = '%s/dir2' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s/file1' % (ADDR, dst),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('dir1' not in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test3'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename4(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 4 - rename a directory to an existing directory (successful
+        mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 4 - rename a directory to an existing directory'):
+            d = 'test4'
+            src = '%s/dir1' % d
+            dst = '%s/dir2' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s/dir1/file1' % (ADDR, dst),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('dir1' not in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test4'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename5(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 5 - rename a directory to an existing file (failed mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 5 - rename a directory to an existing file'):
+            d = 'test5'
+            src = '%s/dir1' % d
+            dst = '%s/file2' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('dir1' in ''.join(output))
+            assert('file2' in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s' % (ADDR, dst),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test5'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename6(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 6 - rename a file to an existing empty directory (failed mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 6 - rename a file to an existing empty directory'):
+            d = 'test6'
+            src = '%s/existing' % d
+            dst = '%s/dir2' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s' % (ADDR, src),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('dir2' in ''.join(output))
+            assert('existing' in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test6'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename7(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 7 - rename a directory to a non-empty directory (failed mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 7 - rename a directory to a non-empty directory'):
+            d = 'test7'
+            src = '%s/dir1' % d
+            dst = '%s/dir2' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s/dir1/file1' % (ADDR, dst),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('dir1' in ''.join(output))
+            assert('dir2' in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test7'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename8(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 8 - rename a directory inside itself (failed mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 8 - rename a directory inside itself'):
+            d = 'test8'
+            src = '%s/dir1' % d
+            dst = '%s/dir1/dir1' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s/file1' % (ADDR, src),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('dir1' in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (src),
+            ])
+            assert('file1' in ''.join(output))
+            assert('dir1' not in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test8'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename9(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 9 - rename a directory inside itself with backtracks (failed
+        mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 9 - rename a directory inside itself with backtracks'):
+            d = 'test9'
+            src = '%s/dir1/nested' % d
+            dst = '%s/dir1/nested/inner/./../../../dir1/nested/inner/another' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, dst),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s/dir1' % (d),
+            ])
+            assert('nested' in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (src),
+            ])
+            assert('inner' in ''.join(output))
+            assert('nested' not in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename10(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 10 - rename a file to itself (successful mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 10 - rename a file to itself'):
+            d = 'test10'
+            src = '%s/file1' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, src),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s' % (ADDR, src),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('file1' in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test10'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)
+
+    def test_rename11(self, u_boot_console, fs_obj_rename):
+        """
+        Test Case 11 - rename a directory to itself (successful mv)
+        """
+        fs_type, fs_img, md5val = fs_obj_rename
+        with u_boot_console.log.section('Test Case 11 - rename a directory to itself'):
+            # / at the end here is intentional. Ensures trailing / doesn't
+            # affect mv producing an updated dst path for fs_rename
+            d = 'test11/'
+            src = '%sdir1' % d
+            output = u_boot_console.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'setenv filesize',
+                'mv host 0:0 %s %s' % (src, d),
+            ])
+            assert('' == ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'load host 0:0 %x /%s/file1' % (ADDR, src),
+                'printenv filesize'])
+            assert('filesize=400' in output)
+
+            output = u_boot_console.run_command_list([
+                'ls host 0:0 %s' % (d),
+            ])
+            assert('dir1' in ''.join(output))
+
+            output = u_boot_console.run_command_list([
+                'md5sum %x $filesize' % ADDR,
+                'setenv filesize'])
+            assert(md5val['test11'] in ''.join(output))
+            assert_fs_integrity(fs_type, fs_img)