Function faccessatW [src]

Same as faccessat except asserts the target is Windows and the path parameter is NtDll-prefixed, null-terminated, WTF-16 encoded.

Prototype

pub fn faccessatW(dirfd: fd_t, sub_path_w: [*:0]const u16) AccessError!void

Parameters

dirfd: fd_tsub_path_w: [*:0]const u16

Possible Errors

AccessDenied

BadPathName

FileBusy

FileNotFound

InputOutput

InvalidUtf8

WASI-only; file paths must be valid UTF-8.

InvalidWtf8

Windows-only; file paths provided by the user must be valid WTF-8. https://simonsapin.github.io/wtf-8/

NameTooLong

PermissionDenied

ReadOnlyFileSystem

SymLinkLoop

SystemResources

Unexpected UnexpectedError

The Operating System returned an undocumented error code.

This error is in theory not possible, but it would be better to handle this error than to invoke undefined behavior.

When this error code is observed, it usually means the Zig Standard Library needs a small patch to add the error code to the error set for the respective function.

Source

  pub fn faccessatW(dirfd: fd_t, sub_path_w: [*:0]const u16) AccessError!void {
    if (sub_path_w[0] == '.' and sub_path_w[1] == 0) {
        return;
    }
    if (sub_path_w[0] == '.' and sub_path_w[1] == '.' and sub_path_w[2] == 0) {
        return;
    }

    const path_len_bytes = cast(u16, mem.sliceTo(sub_path_w, 0).len * 2) orelse return error.NameTooLong;
    var nt_name = windows.UNICODE_STRING{
        .Length = path_len_bytes,
        .MaximumLength = path_len_bytes,
        .Buffer = @constCast(sub_path_w),
    };
    var attr = windows.OBJECT_ATTRIBUTES{
        .Length = @sizeOf(windows.OBJECT_ATTRIBUTES),
        .RootDirectory = if (fs.path.isAbsoluteWindowsW(sub_path_w)) null else dirfd,
        .Attributes = 0, // Note we do not use OBJ_CASE_INSENSITIVE here.
        .ObjectName = &nt_name,
        .SecurityDescriptor = null,
        .SecurityQualityOfService = null,
    };
    var basic_info: windows.FILE_BASIC_INFORMATION = undefined;
    switch (windows.ntdll.NtQueryAttributesFile(&attr, &basic_info)) {
        .SUCCESS => return,
        .OBJECT_NAME_NOT_FOUND => return error.FileNotFound,
        .OBJECT_PATH_NOT_FOUND => return error.FileNotFound,
        .OBJECT_NAME_INVALID => unreachable,
        .INVALID_PARAMETER => unreachable,
        .ACCESS_DENIED => return error.AccessDenied,
        .OBJECT_PATH_SYNTAX_BAD => unreachable,
        else => |rc| return windows.unexpectedStatus(rc),
    }
}  