Detect a UEFI partition

pdo debian eng sw

Today I had to implement a check to see if a disk contains a UEFI ESP partition.

Here it is, it also works on disk image files instead of devices:

def get_uefi_partition(self, disk_dev):
    """
    Return the partition device of the UEFI ESP partition for the device in
    disk_dev.

    Returns None if disk_dev contains no UEFI ESP partition.
    """
    import parted
    pdev = parted.getDevice(disk_dev)
    pdisk = parted.newDisk(pdev)
    if pdisk.type != "gpt":
        log.error("device %s has partition table type %s instead of gpt", disk_dev, pdisk.type)
        return None
    for part in pdisk.partitions:
        if part.getFlag(18):
            log.info("Found ESP partition in %s", part.path)
            return part.path
    log.info("No ESP partition found in %s", disk_dev)
    return None