Commit b35874a4292526b3d6ab33b24b8fbd0d1596e216 | zig

author	Andrew Kelley <andrew@ziglang.org> 2023-07-23 11:37:11-07:00
committer	GitHub <noreply@github.com> 2023-07-23 11:37:11-07:00
log	b35874a4292526b3d6ab33b24b8fbd0d1596e216
tree	3c4cbab05d69d56d71eb94280acec7959a285d9e
parent	1bf16b1723445ba307ca556dc050d6d13bb0ebff
parent	21ecb1ba0fabe471476df9ca328c8aa14767af24
signature	Signed by PGP key 4AEE18F83AFDEB23

Merge pull request #16499 from squeek502/posix-semantics-2

windows.DeleteFile: Use FileDispositionInformationEx if possible, but fallback if not

2 files changed, 32 insertions(+), 27 deletions(-)

lib
- std
  - fs
    test.zig
  - os
    windows.zig

lib/std/fs/test.zig+18-25

...	@@ -1416,34 +1416,13 @@ test "File.PermissionsUnix" {	...	@@ -1416,34 +1416,13 @@ test "File.PermissionsUnix" {
1416	try testing.expect(!permissions_unix.unixHas(.other, .execute));	1416	try testing.expect(!permissions_unix.unixHas(.other, .execute));
1417	}	1417	}
1418		1418
1419	test "delete a read-only file on windows with file pending semantics" {	1419	test "delete a read-only file on windows" {
1420	if (builtin.os.tag != .windows or builtin.target.os.version_range.windows.min.isAtLeast(.win10_rs1))	1420	if (builtin.os.tag != .windows)
1421	return error.SkipZigTest;	1421	return error.SkipZigTest;
1422		1422
1423	var tmp = tmpDir(.{});	1423	var tmp = testing.tmpDir(.{});
1424	defer tmp.cleanup();	1424	defer tmp.cleanup();
1425	{
1426	const file = try tmp.dir.createFile("test_file", .{ .read = true });
1427	defer file.close();
1428	// Create a file and make it read-only
1429	const metadata = try file.metadata();
1430	var permissions = metadata.permissions();
1431	permissions.setReadOnly(true);
1432	try file.setPermissions(permissions);
1433	try testing.expectError(error.AccessDenied, tmp.dir.deleteFile("test_file"));
1434	// Now make the file not read-only
1435	permissions.setReadOnly(false);
1436	try file.setPermissions(permissions);
1437	}
1438	try tmp.dir.deleteFile("test_file");
1439	}
1440
1441	test "delete a read-only file on windows with posix semantis" {
1442	if (builtin.os.tag != .windows or !builtin.target.os.version_range.windows.min.isAtLeast(.win10_rs1))
1443	return error.SkipZigTest;
1444		1425
1445	var tmp = tmpDir(.{});
1446	defer tmp.cleanup();
1447	const file = try tmp.dir.createFile("test_file", .{ .read = true });	1426	const file = try tmp.dir.createFile("test_file", .{ .read = true });
1448	defer file.close();	1427	defer file.close();
1449	// Create a file and make it read-only	1428	// Create a file and make it read-only
...	@@ -1451,7 +1430,21 @@ test "delete a read-only file on windows with posix semantis" {	...	@@ -1451,7 +1430,21 @@ test "delete a read-only file on windows with posix semantis" {
1451	var permissions = metadata.permissions();	1430	var permissions = metadata.permissions();
1452	permissions.setReadOnly(true);	1431	permissions.setReadOnly(true);
1453	try file.setPermissions(permissions);	1432	try file.setPermissions(permissions);
1454	try tmp.dir.deleteFile("test_file"); // file is unmapped and deleted once last handle closed	1433
		1434	// If the OS and filesystem support it, POSIX_SEMANTICS and IGNORE_READONLY_ATTRIBUTE
		1435	// is used meaning that the deletion of a read-only file will succeed.
		1436	// Otherwise, this delete will fail and the read-only flag must be unset before it's
		1437	// able to be deleted.
		1438	const delete_result = tmp.dir.deleteFile("test_file");
		1439	if (delete_result) {
		1440	try testing.expectError(error.FileNotFound, tmp.dir.deleteFile("test_file"));
		1441	} else \|err\| {
		1442	try testing.expectEqual(@as(anyerror, error.AccessDenied), err);
		1443	// Now make the file not read-only
		1444	permissions.setReadOnly(false);
		1445	try file.setPermissions(permissions);
		1446	try tmp.dir.deleteFile("test_file");
		1447	}
1455	}	1448	}
1456		1449
1457	test "delete a setAsCwd directory on Windows" {	1450	test "delete a setAsCwd directory on Windows" {

lib/std/os/windows.zig+14-2

 @@ -940,8 +940,13 @@ pub fn DeleteFile(sub_path_w: []const u16, options: DeleteFileOptions) DeleteFil
     }
     defer CloseHandle(tmp_handle);
+    // FileDispositionInformationEx (and therefore FILE_DISPOSITION_POSIX_SEMANTICS and FILE_DISPOSITION_IGNORE_READONLY_ATTRIBUTE)
+    // are only supported on NTFS filesystems, so the version check on its own is only a partial solution. To support non-NTFS filesystems
+    // like FAT32, we need to fallback to FileDispositionInformation if the usage of FileDispositionInformationEx gives
+    // us INVALID_PARAMETER.
+    var need_fallback = true;
     if (comptime builtin.target.os.version_range.windows.min.isAtLeast(.win10_rs1)) {
-        // Deletion with posix semantics.
+        // Deletion with posix semantics if the filesystem supports it.
         var info = FILE_DISPOSITION_INFORMATION_EX{
             .Flags = FILE_DISPOSITION_DELETE |
                 FILE_DISPOSITION_POSIX_SEMANTICS |
 @@ -955,7 +960,14 @@ pub fn DeleteFile(sub_path_w: []const u16, options: DeleteFileOptions) DeleteFil
             @sizeOf(FILE_DISPOSITION_INFORMATION_EX),
             .FileDispositionInformationEx,
         );
-    } else {
+        switch (rc) {
+            // INVALID_PARAMETER here means that the filesystem does not support FileDispositionInformationEx
+            .INVALID_PARAMETER => {},
+            // For all other statuses, fall down to the switch below to handle them.
+            else => need_fallback = false,
+        }
+    }
+    if (need_fallback) {
         // Deletion with file pending semantics, which requires waiting or moving
         // files to get them removed (from here).
         var file_dispo = FILE_DISPOSITION_INFORMATION{