QueryObjectName

pub fn QueryObjectName(handle: windows.HANDLE, out_buffer: []u16) QueryObjectNameError![]u16

File

Code

pub fn QueryObjectName(handle: windows.HANDLE, out_buffer: []u16) QueryObjectNameError![]u16 {
    const out_buffer_aligned = std.mem.alignInSlice(out_buffer, @alignOf(windows.OBJECT.NAME_INFORMATION)) orelse return error.NameTooLong;

    const info: *windows.OBJECT.NAME_INFORMATION = @ptrCast(out_buffer_aligned);
    // buffer size is specified in bytes
    const out_buffer_len = std.math.cast(windows.ULONG, out_buffer_aligned.len * 2) orelse std.math.maxInt(windows.ULONG);
    // last argument would return the length required for full_buffer, not exposed here
    return switch (windows.ntdll.NtQueryObject(handle, .Name, info, out_buffer_len, null)) {
        .SUCCESS => {
            // info.Name from ObQueryNameString is documented to be empty if the object
            // was "unnamed", not sure if this can happen for file handles
            return if (info.Name.isEmpty()) error.Unexpected else info.Name.slice();
        },
        .ACCESS_DENIED => error.AccessDenied,
        .INVALID_HANDLE => error.InvalidHandle,
        // triggered when the buffer is too small for the OBJECT_NAME_INFORMATION object (.INFO_LENGTH_MISMATCH),
        // or if the buffer is too small for the file path returned (.BUFFER_OVERFLOW, .BUFFER_TOO_SMALL)
        .INFO_LENGTH_MISMATCH, .BUFFER_OVERFLOW, .BUFFER_TOO_SMALL => error.NameTooLong,
        else => |e| windows.unexpectedStatus(e),
    };
}