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|
open Printf
let () =
NBD.with_handle (
fun nbd ->
NBD.add_meta_context nbd "base:allocation";
NBD.connect_command nbd
["nbdkit"; "-s"; "--exit-with-parent"; "-r";
"sparse-random"; "8G"];
(* Read the extents and print them. *)
let size = NBD.get_size nbd in
let fetch_offset = ref 0_L in
while !fetch_offset < size do
let remaining = Int64.sub size !fetch_offset in
let fetch_size = min remaining 0x8000_0000_L in
NBD.block_status nbd fetch_size !fetch_offset (
fun meta _ entries err ->
printf "nbd_block_status callback: meta=%s err=%d\n" meta !err;
if meta = "base:allocation" then (
printf "index\t%16s %16s %s\n" "offset" "length" "flags";
for i = 0 to Array.length entries / 2 - 1 do
let len = entries.(i*2)
and flags =
match entries.(i*2+1) with
| 0_L -> "data"
| 1_L -> "hole"
| 2_L -> "zero"
| 3_L -> "hole+zero"
| unknown -> sprintf "unknown (%Ld)" unknown in
printf "%d:\t%16Ld %16Ld %s\n" i !fetch_offset len flags;
fetch_offset := Int64.add !fetch_offset len
done;
);
0
) (* NBD.block_status *)
done
)
|
