windows.DeleteFile Does not fail on non-empty directories

[xEgoist]

Zig Version

0.11.0-dev.2613+b42562be7

Steps to Reproduce and Observed Behavior

Upon reading this unrelated issue: dokan-dev/dokany#883,
I learned that calling NtCreateFile with FILE_DELETE_ON_CLOSE does not fail on non-empty directories, but simply mark it as DELETE_PENDING with a success NTSTATUS.

Here are simple steps to reproduce this bug:

1- Create any folder, here i am using C:\example
2- Create any empty file inside it C:\example\test.txt

run the following:

const std = @import("std");

pub fn main() !void {
    var fd = try std.fs.openDirAbsolute("C:\\", .{});
    defer fd.close();
    try fd.deleteDir("example");
}

deleteDir will not complain and the folder will not be removed, which is not what the docs says here

Expected Behavior

DIRECTORY_NOT_EMPTY/error.DirNotEmpty should be returned.

---

Side Note: I am mostly guessing here, and haven't looked deeply in the changes, but I think that the recent CI timeouts #14948 are caused by windows.OpenFile infinite looping through DELETE_PENDING due to this (again, i could definately be wrong here).

zig/lib/std/os/windows.zig

Lines 141 to 156 in 23ac4dd

	.USER_MAPPED_FILE => return error.AccessDenied,
	.INVALID_HANDLE => unreachable,
	.DELETE_PENDING => {
	// This error means that there *was* a file in this location on
	// the file system, but it was deleted. However, the OS is not
	// finished with the deletion operation, and so this CreateFile
	// call has failed. There is not really a sane way to handle
	// this other than retrying the creation after the OS finishes
	// the deletion.
	std.time.sleep(std.time.ns_per_ms);
	continue;
	},
	else => return unexpectedStatus(rc),
	}
	}
	}

---

Solution/Alternative Delete Functions

I explored few solutions to resolve this bug to find out how other delete functions works:

• kernel32!RemoveDirectory() returns false and sets the last error to 145 - Directory not empty. I haven't traced it, but i assume it calls SetInformationFile.
• ntdll!NtDeleteFile Marks for deletion and silently fails as well (There is some controversy if it just sets FILE_DELETE_ON_CLOSE ).
• Open for deletion + ntdll!NtSetInformationFile with FileDispositionInformation: this marks it for deletion and reports if not-empty.

[squeek502]

Duplicate of #5537

Also relevant: #6452

[xEgoist]

Duplicate of #5537

Also relevant: #6452

I apologize for not doing a better search. Thanks for pointing that out.