func findUpdatedFiles(dir *C.DIR, rootId, oldestGen uint64) (uint64, error) {
var maxFound uint64 = 0
var args C.struct_btrfs_ioctl_search_args
var sk *C.struct_btrfs_ioctl_search_key = &args.key
var sh C.struct_btrfs_ioctl_search_header
var item *BtrfsFileExtentItem
var backup BtrfsFileExtentItem
var foundGen uint64 = 0
sk.tree_id = C.__u64(rootId)
sk.max_objectid = math.MaxUint64
sk.max_offset = math.MaxUint64
sk.max_transid = math.MaxUint64
sk.max_type = C.BTRFS_EXTENT_DATA_KEY
sk.min_transid = C.__u64(oldestGen)
sk.nr_items = 4096
fd := getDirFd(dir)
maxFound, err := findRootGen(dir)
if err != nil {
return 0, err
}
for {
_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, fd, C.BTRFS_IOC_TREE_SEARCH, uintptr(unsafe.Pointer(&args)))
if errno != 0 {
return 0, fmt.Errorf("Failed to perform the search %v", errno.Error())
}
if sk.nr_items == 0 {
break
}
var off uintptr = 0
for i := uint32(0); i < uint32(sk.nr_items); i++ {
C.memcpy(unsafe.Pointer(&sh), addptr(unsafe.Pointer(&args.buf), off), C.sizeof_struct_btrfs_ioctl_search_header)
off += C.sizeof_struct_btrfs_ioctl_search_header
if sh.len == 0 {
item = &backup
} else {
rawItem := (*C.struct_btrfs_file_extent_item)(addptr(unsafe.Pointer(&args.buf), off))
item, err = NewBtrfsFileExtentItem(rawItem)
if err != nil {
return 0, err
}
}
foundGen = item.Generation
if sh._type == C.BTRFS_EXTENT_DATA_KEY && foundGen >= uint64(oldestGen) {
// print...
}
off += uintptr(sh.len)
sk.min_objectid = sh.objectid
sk.min_offset = sh.offset
sk.min_type = sh._type
}
sk.nr_items = 4096
if sk.min_offset < math.MaxUint64 {
sk.min_offset++
} else if sk.min_objectid < math.MaxUint64 {
sk.min_objectid++
sk.min_offset = 0
sk.min_type = 0
} else {
break
}
}
return maxFound, nil
}
