MinaProtocol / mina / 507

Committed 19 Aug 2025 11:53PM UTC coverage: 33.38% (-28.0%) from 61.334%

Build # 507

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Merge pull request #17640 from MinaProtocol/georgeee/compatible-to-develop-2025-08-19

Merge `compatible` to `develop` (19 August 2025, pt. 2)

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/src/lib/transition_frontier/persistent_root/persistent_root.ml

open Core
open Mina_base
module Ledger = Mina_ledger.Ledger
open Frontier_base
module Ledger_transfer = Mina_ledger.Ledger_transfer.Make (Ledger) (Ledger.Db)
module Ledger_transfer_stable =
  Mina_ledger.Ledger_transfer.Make (Ledger.Db) (Ledger.Db)

let transfer_snarked_root =
  Ledger.Root.transfer_accounts_with
    ~stable:Ledger_transfer_stable.transfer_accounts

let genesis_root_identifier ~genesis_state_hash =
  let open Root_identifier.Stable.Latest in
  { state_hash = genesis_state_hash }

let with_file ?size filename access_level ~f =
  let open Unix in
  let shared, mode =
    match access_level with
    | `Read ->
        (false, [ O_RDONLY ])
    | `Write ->
        (true, [ O_RDWR; O_TRUNC; O_CREAT ])
  in
  let fd = Unix.openfile filename ~mode in
  let buf_size =
    match size with
    | None ->
        Int64.to_int_exn Unix.(fstat fd).st_size
    | Some sz ->
        sz
  in
  (* Bigstring.map_file has been removed. We copy its old implementation. *)
  let buf =
    Bigarray.(
      array1_of_genarray
        (Core.Unix.map_file fd char c_layout ~shared [| buf_size |]))
  in
  let x = f buf in
  Bigstring.unsafe_destroy buf ;
  Unix.close fd ;
  x

(* TODO: create a reusable singleton factory abstraction *)
module rec Instance_type : sig
  type t =
    { snarked_ledger : Ledger.Root.t
    ; potential_snarked_ledgers : string Queue.t
    ; factory : Factory_type.t
    }
end =
  Instance_type

and Factory_type : sig
  type t =
    { directory : string
    ; logger : Logger.t
    ; mutable instance : Instance_type.t option
    ; ledger_depth : int
    }
end =
  Factory_type

open Instance_type
open Factory_type

module Instance = struct
  type t = Instance_type.t

  module Locations = struct
    (** Helper to create a filesystem location (for a file or directory) inside
        the [Factory_type.t] directory. *)
    let make_instance_location filename t = Filename.concat t.directory filename

    (** The directory name for the actual snarked ledger that is initialized and
        used by the daemon *)
    let snarked_ledger = make_instance_location "snarked_ledger"

    (** The directory name for a temporary snarked ledger, used while recovering
        a vaild potential snarked ledger during startup *)
    let tmp_snarked_ledger = make_instance_location "tmp_snarked_ledger"

    (** The name of a json file that lists the directory names of the potential
        snarked ledgers in the [potential_snarked_ledgers] queue *)
    let potential_snarked_ledgers =
      make_instance_location "potential_snarked_ledgers.json"

    (** A method that generates fresh potential snarked ledger directory
        names *)
    let make_potential_snarked_ledger t =
      let uuid = Uuid_unix.create () in
      make_instance_location ("snarked_ledger" ^ Uuid.to_string_hum uuid) t

    (** The name of the file recording the [Root_identifier.t] of the snarked
        root *)
    let root_identifier = make_instance_location "root"
  end

  let potential_snarked_ledgers_to_yojson queue =
    `List (List.map (Queue.to_list queue) ~f:(fun filename -> `String filename))

  let potential_snarked_ledgers_of_yojson json =
    Yojson.Safe.Util.to_list json |> List.map ~f:Yojson.Safe.Util.to_string

  let load_potential_snarked_ledgers_from_disk factory =
    let location = Locations.potential_snarked_ledgers factory in
    if phys_equal (Sys.file_exists location) `Yes then
      Yojson.Safe.from_file location |> potential_snarked_ledgers_of_yojson
    else []

  let write_potential_snarked_ledgers_to_disk t =
    Yojson.Safe.to_file
      (Locations.potential_snarked_ledgers t.factory)
      (potential_snarked_ledgers_to_yojson t.potential_snarked_ledgers)

  let enqueue_snarked_ledger ~location t =
    Queue.enqueue t.potential_snarked_ledgers location ;
    write_potential_snarked_ledgers_to_disk t

  let dequeue_snarked_ledger t =
    let location = Queue.dequeue_exn t.potential_snarked_ledgers in
    Mina_stdlib_unix.File_system.rmrf location ;
    write_potential_snarked_ledgers_to_disk t

  let destroy t =
    List.iter
      (Queue.to_list t.potential_snarked_ledgers)
      ~f:Mina_stdlib_unix.File_system.rmrf ;
    Mina_stdlib_unix.File_system.rmrf
      (Locations.potential_snarked_ledgers t.factory) ;
    Ledger.Root.close t.snarked_ledger ;
    t.factory.instance <- None

  let close t =
    Ledger.Root.close t.snarked_ledger ;
    t.factory.instance <- None

  let create factory =
    let snarked_ledger =
      Ledger.Root.create_single ~depth:factory.ledger_depth
        ~directory_name:(Locations.snarked_ledger factory)
        ()
    in
    { snarked_ledger; potential_snarked_ledgers = Queue.create (); factory }

  (** When we load from disk,
      1. Check the potential_snarked_ledgers to see if any one of these
         matches the snarked_ledger_hash in persistent_frontier;
      2. if none of those works, we load the old snarked_ledger and check if
         the old snarked_ledger matches with persistent_frontier;
      3. if not, we just reset all the persisted data and start from genesis
   *)
  let load_from_disk factory ~snarked_ledger_hash ~logger =
    let potential_snarked_ledgers =
      load_potential_snarked_ledgers_from_disk factory
    in
    let snarked_ledger =
      List.fold_until potential_snarked_ledgers ~init:None
        ~f:(fun _ location ->
          let potential_snarked_ledger =
            Ledger.Root.create_single ~depth:factory.ledger_depth
              ~directory_name:location ()
          in
          let potential_snarked_ledger_hash =
            Frozen_ledger_hash.of_ledger_hash
            @@ Ledger.Root.merkle_root potential_snarked_ledger
          in
          [%log debug]
            ~metadata:
              [ ( "potential_snarked_ledger_hash"
                , Frozen_ledger_hash.to_yojson potential_snarked_ledger_hash )
              ]
            "loaded potential_snarked_ledger from disk" ;
          if
            Frozen_ledger_hash.equal potential_snarked_ledger_hash
              snarked_ledger_hash
          then (
            let snarked_ledger =
              Ledger.Root.create_single ~depth:factory.ledger_depth
                ~directory_name:(Locations.tmp_snarked_ledger factory)
                ()
            in
            match
              transfer_snarked_root ~src:potential_snarked_ledger
                ~dest:snarked_ledger
            with
            | Ok _ ->
                Ledger.Root.close potential_snarked_ledger ;
                Mina_stdlib_unix.File_system.rmrf
                @@ Locations.snarked_ledger factory ;
                Sys.rename
                  (Locations.tmp_snarked_ledger factory)
                  (Locations.snarked_ledger factory) ;
                List.iter potential_snarked_ledgers
                  ~f:Mina_stdlib_unix.File_system.rmrf ;
                Mina_stdlib_unix.File_system.rmrf
                  (Locations.potential_snarked_ledgers factory) ;
                Stop (Some snarked_ledger)
            | Error e ->
                Ledger.Root.close potential_snarked_ledger ;
                List.iter potential_snarked_ledgers
                  ~f:Mina_stdlib_unix.File_system.rmrf ;
                Mina_stdlib_unix.File_system.rmrf
                  (Locations.potential_snarked_ledgers factory) ;
                [%log' error factory.logger]
                  ~metadata:[ ("error", `String (Error.to_string_hum e)) ]
                  "Ledger_transfer failed" ;
                Stop None )
          else (
            Ledger.Root.close potential_snarked_ledger ;
            Continue None ) )
        ~finish:(fun _ ->
          List.iter potential_snarked_ledgers
            ~f:Mina_stdlib_unix.File_system.rmrf ;
          Mina_stdlib_unix.File_system.rmrf
            (Locations.potential_snarked_ledgers factory) ;
          None )
    in
    match snarked_ledger with
    | None ->
        let snarked_ledger =
          Ledger.Root.create_single ~depth:factory.ledger_depth
            ~directory_name:(Locations.snarked_ledger factory)
            ()
        in
        let potential_snarked_ledger_hash =
          Frozen_ledger_hash.of_ledger_hash
          @@ Ledger.Root.merkle_root snarked_ledger
        in
        if
          Frozen_ledger_hash.equal potential_snarked_ledger_hash
            snarked_ledger_hash
        then
          Ok
            { snarked_ledger
            ; potential_snarked_ledgers = Queue.create ()
            ; factory
            }
        else (
          Ledger.Root.close snarked_ledger ;
          Error `Snarked_ledger_mismatch )
    | Some snarked_ledger ->
        Ok
          { snarked_ledger
          ; potential_snarked_ledgers = Queue.create ()
          ; factory
          }

  let snarked_ledger { snarked_ledger; _ } = snarked_ledger

  let set_root_identifier t new_root_identifier =
    [%log' trace t.factory.logger]
      ~metadata:
        [ ("root_identifier", Root_identifier.to_yojson new_root_identifier) ]
      "Setting persistent root identifier" ;
    let size = Root_identifier.Stable.Latest.bin_size_t new_root_identifier in
    with_file (Locations.root_identifier t.factory) `Write ~size ~f:(fun buf ->
        ignore
          ( Root_identifier.Stable.Latest.bin_write_t buf ~pos:0
              new_root_identifier
            : int ) )

  (* defaults to genesis *)
  let load_root_identifier t =
    let file = Locations.root_identifier t.factory in
    match Unix.access file [ `Exists; `Read ] with
    | Error _ ->
        None
    | Ok () ->
        with_file file `Read ~f:(fun buf ->
            let root_identifier =
              Root_identifier.Stable.Latest.bin_read_t buf ~pos_ref:(ref 0)
            in
            [%log' trace t.factory.logger]
              ~metadata:
                [ ("root_identifier", Root_identifier.to_yojson root_identifier)
                ]
              "Loaded persistent root identifier" ;
            Some root_identifier )

  let set_root_state_hash t state_hash = set_root_identifier t { state_hash }
end

type t = Factory_type.t

let create ~logger ~directory ~ledger_depth =
  { directory; logger; instance = None; ledger_depth }

let create_instance_exn t =
  assert (Option.is_none t.instance) ;
  let instance = Instance.create t in
  t.instance <- Some instance ;
  instance

let load_from_disk_exn t ~snarked_ledger_hash ~logger =
  let open Result.Let_syntax in
  assert (Option.is_none t.instance) ;
  let%map instance = Instance.load_from_disk t ~snarked_ledger_hash ~logger in
  t.instance <- Some instance ;
  instance

let with_instance_exn t ~f =
  let instance = create_instance_exn t in
  let x = f instance in
  Instance.close instance ; x

let reset_to_genesis_exn t ~precomputed_values =
  assert (Option.is_none t.instance) ;
  Mina_stdlib_unix.File_system.rmrf t.directory ;
  with_instance_exn t ~f:(fun instance ->
      ignore
        ( Precomputed_values.populate_root precomputed_values
            (Instance.snarked_ledger instance)
          |> Or_error.map ~f:Ledger.Root.as_unmasked
          : Ledger.Any_ledger.witness Or_error.t ) ;
      Instance.set_root_identifier instance
        (genesis_root_identifier
           ~genesis_state_hash:
             (Precomputed_values.genesis_state_hashes precomputed_values)
               .state_hash ) )

1	open Core	49✔
2	open Mina_base
3	module Ledger = Mina_ledger.Ledger
4	open Frontier_base
5	module Ledger_transfer = Mina_ledger.Ledger_transfer.Make (Ledger) (Ledger.Db)
6	module Ledger_transfer_stable =
7	Mina_ledger.Ledger_transfer.Make (Ledger.Db) (Ledger.Db)
8
9	let transfer_snarked_root =
10	Ledger.Root.transfer_accounts_with
11	~stable:Ledger_transfer_stable.transfer_accounts
12
13	let genesis_root_identifier ~genesis_state_hash =
14	let open Root_identifier.Stable.Latest in	×
15	{ state_hash = genesis_state_hash }
16
17	let with_file ?size filename access_level ~f =
18	let open Unix in	×
19	let shared, mode =
20	match access_level with
21	\| `Read ->	×
22	(false, [ O_RDONLY ])
23	\| `Write ->	×
24	(true, [ O_RDWR; O_TRUNC; O_CREAT ])
25	in
26	let fd = Unix.openfile filename ~mode in
27	let buf_size =	×
28	match size with
29	\| None ->	×
30	Int64.to_int_exn Unix.(fstat fd).st_size	×
31	\| Some sz ->	×
32	sz
33	in
34	(* Bigstring.map_file has been removed. We copy its old implementation. *)
35	let buf =
36	Bigarray.(
37	array1_of_genarray	×
38	(Core.Unix.map_file fd char c_layout ~shared [\| buf_size \|]))	×
39	in
40	let x = f buf in
41	Bigstring.unsafe_destroy buf ;	×
42	Unix.close fd ;	×
43	x	×
44
45	(* TODO: create a reusable singleton factory abstraction *)
46	module rec Instance_type : sig
47	type t =
48	{ snarked_ledger : Ledger.Root.t
49	; potential_snarked_ledgers : string Queue.t
50	; factory : Factory_type.t
51	}
52	end =
53	Instance_type
54
55	and Factory_type : sig
56	type t =
57	{ directory : string
58	; logger : Logger.t
59	; mutable instance : Instance_type.t option
60	; ledger_depth : int
61	}
62	end =
63	Factory_type
64
65	open Instance_type
66	open Factory_type
67
68	module Instance = struct
69	type t = Instance_type.t
70
71	module Locations = struct
72	(** Helper to create a filesystem location (for a file or directory) inside
73	the [Factory_type.t] directory. *)
74	let make_instance_location filename t = Filename.concat t.directory filename	×
75
76	(** The directory name for the actual snarked ledger that is initialized and
77	used by the daemon *)
78	let snarked_ledger = make_instance_location "snarked_ledger"	49✔
79
80	(** The directory name for a temporary snarked ledger, used while recovering
81	a vaild potential snarked ledger during startup *)
82	let tmp_snarked_ledger = make_instance_location "tmp_snarked_ledger"	49✔
83
84	(** The name of a json file that lists the directory names of the potential
85	snarked ledgers in the [potential_snarked_ledgers] queue *)
86	let potential_snarked_ledgers =
87	make_instance_location "potential_snarked_ledgers.json"	49✔
88
89	(** A method that generates fresh potential snarked ledger directory
90	names *)
91	let make_potential_snarked_ledger t =
92	let uuid = Uuid_unix.create () in	×
93	make_instance_location ("snarked_ledger" ^ Uuid.to_string_hum uuid) t	×
94
95	(** The name of the file recording the [Root_identifier.t] of the snarked
96	root *)
97	let root_identifier = make_instance_location "root"	49✔
98	end
99
100	let potential_snarked_ledgers_to_yojson queue =
101	`List (List.map (Queue.to_list queue) ~f:(fun filename -> `String filename))	×
102
103	let potential_snarked_ledgers_of_yojson json =
104	Yojson.Safe.Util.to_list json \|> List.map ~f:Yojson.Safe.Util.to_string	×
105
106	let load_potential_snarked_ledgers_from_disk factory =
107	let location = Locations.potential_snarked_ledgers factory in	×
108	if phys_equal (Sys.file_exists location) `Yes then	×
109	Yojson.Safe.from_file location \|> potential_snarked_ledgers_of_yojson	×
110	else []	×
111
112	let write_potential_snarked_ledgers_to_disk t =
113	Yojson.Safe.to_file	×
114	(Locations.potential_snarked_ledgers t.factory)	×
115	(potential_snarked_ledgers_to_yojson t.potential_snarked_ledgers)	×
116
117	let enqueue_snarked_ledger ~location t =
118	Queue.enqueue t.potential_snarked_ledgers location ;	×
119	write_potential_snarked_ledgers_to_disk t	×
120
121	let dequeue_snarked_ledger t =
122	let location = Queue.dequeue_exn t.potential_snarked_ledgers in	×
123	Mina_stdlib_unix.File_system.rmrf location ;	×
124	write_potential_snarked_ledgers_to_disk t	×
125
126	let destroy t =
127	List.iter	×
128	(Queue.to_list t.potential_snarked_ledgers)	×
129	~f:Mina_stdlib_unix.File_system.rmrf ;
130	Mina_stdlib_unix.File_system.rmrf	×
131	(Locations.potential_snarked_ledgers t.factory) ;	×
132	Ledger.Root.close t.snarked_ledger ;	×
133	t.factory.instance <- None	×
134
135	let close t =
136	Ledger.Root.close t.snarked_ledger ;	×
137	t.factory.instance <- None	×
138
139	let create factory =
140	let snarked_ledger =	×
141	Ledger.Root.create_single ~depth:factory.ledger_depth
142	~directory_name:(Locations.snarked_ledger factory)	×
143	()
144	in
145	{ snarked_ledger; potential_snarked_ledgers = Queue.create (); factory }	×
146
147	(** When we load from disk,
148	1. Check the potential_snarked_ledgers to see if any one of these
149	matches the snarked_ledger_hash in persistent_frontier;
150	2. if none of those works, we load the old snarked_ledger and check if
151	the old snarked_ledger matches with persistent_frontier;
152	3. if not, we just reset all the persisted data and start from genesis
153	*)
154	let load_from_disk factory ~snarked_ledger_hash ~logger =
155	let potential_snarked_ledgers =	×
156	load_potential_snarked_ledgers_from_disk factory
157	in
158	let snarked_ledger =	×
159	List.fold_until potential_snarked_ledgers ~init:None
160	~f:(fun _ location ->
161	let potential_snarked_ledger =	×
162	Ledger.Root.create_single ~depth:factory.ledger_depth
163	~directory_name:location ()
164	in
165	let potential_snarked_ledger_hash =	×
166	Frozen_ledger_hash.of_ledger_hash
167	@@ Ledger.Root.merkle_root potential_snarked_ledger	×
168	in
169	[%log debug]	×
170	~metadata:
171	[ ( "potential_snarked_ledger_hash"
172	, Frozen_ledger_hash.to_yojson potential_snarked_ledger_hash )	×
173	]
174	"loaded potential_snarked_ledger from disk" ;
175	if	×
176	Frozen_ledger_hash.equal potential_snarked_ledger_hash
177	snarked_ledger_hash
178	then (	×
179	let snarked_ledger =
180	Ledger.Root.create_single ~depth:factory.ledger_depth
181	~directory_name:(Locations.tmp_snarked_ledger factory)	×
182	()
183	in
184	match	×
185	transfer_snarked_root ~src:potential_snarked_ledger
186	~dest:snarked_ledger
187	with
188	\| Ok _ ->	×
189	Ledger.Root.close potential_snarked_ledger ;
190	Mina_stdlib_unix.File_system.rmrf	×
191	@@ Locations.snarked_ledger factory ;	×
192	Sys.rename	×
193	(Locations.tmp_snarked_ledger factory)	×
194	(Locations.snarked_ledger factory) ;	×
195	List.iter potential_snarked_ledgers	×
196	~f:Mina_stdlib_unix.File_system.rmrf ;
197	Mina_stdlib_unix.File_system.rmrf	×
198	(Locations.potential_snarked_ledgers factory) ;	×
199	Stop (Some snarked_ledger)	×
200	\| Error e ->	×
201	Ledger.Root.close potential_snarked_ledger ;
202	List.iter potential_snarked_ledgers	×
203	~f:Mina_stdlib_unix.File_system.rmrf ;
204	Mina_stdlib_unix.File_system.rmrf	×
205	(Locations.potential_snarked_ledgers factory) ;	×
206	[%log' error factory.logger]	×
207	~metadata:[ ("error", `String (Error.to_string_hum e)) ]	×
208	"Ledger_transfer failed" ;
209	Stop None )	×
210	else (	×
211	Ledger.Root.close potential_snarked_ledger ;
212	Continue None ) )	×
213	~finish:(fun _ ->
214	List.iter potential_snarked_ledgers	×
215	~f:Mina_stdlib_unix.File_system.rmrf ;
216	Mina_stdlib_unix.File_system.rmrf	×
217	(Locations.potential_snarked_ledgers factory) ;	×
218	None )	×
219	in
220	match snarked_ledger with	×
221	\| None ->	×
222	let snarked_ledger =
223	Ledger.Root.create_single ~depth:factory.ledger_depth
224	~directory_name:(Locations.snarked_ledger factory)	×
225	()
226	in
227	let potential_snarked_ledger_hash =	×
228	Frozen_ledger_hash.of_ledger_hash
229	@@ Ledger.Root.merkle_root snarked_ledger	×
230	in
231	if	×
232	Frozen_ledger_hash.equal potential_snarked_ledger_hash
233	snarked_ledger_hash
234	then
235	Ok	×
236	{ snarked_ledger
237	; potential_snarked_ledgers = Queue.create ()	×
238	; factory
239	}
240	else (	×
241	Ledger.Root.close snarked_ledger ;
242	Error `Snarked_ledger_mismatch )	×
243	\| Some snarked_ledger ->	×
244	Ok
245	{ snarked_ledger
246	; potential_snarked_ledgers = Queue.create ()	×
247	; factory
248	}
249
250	let snarked_ledger { snarked_ledger; _ } = snarked_ledger	×
251
252	let set_root_identifier t new_root_identifier =
253	[%log' trace t.factory.logger]	×
254	~metadata:
255	[ ("root_identifier", Root_identifier.to_yojson new_root_identifier) ]	×
256	"Setting persistent root identifier" ;
257	let size = Root_identifier.Stable.Latest.bin_size_t new_root_identifier in	×
258	with_file (Locations.root_identifier t.factory) `Write ~size ~f:(fun buf ->	×
259	ignore	×
260	( Root_identifier.Stable.Latest.bin_write_t buf ~pos:0	×
261	new_root_identifier
262	: int ) )
263
264	(* defaults to genesis *)
265	let load_root_identifier t =
266	let file = Locations.root_identifier t.factory in	×
267	match Unix.access file [ `Exists; `Read ] with	×
268	\| Error _ ->	×
269	None
270	\| Ok () ->	×
271	with_file file `Read ~f:(fun buf ->
272	let root_identifier =	×
273	Root_identifier.Stable.Latest.bin_read_t buf ~pos_ref:(ref 0)
274	in
275	[%log' trace t.factory.logger]	×
276	~metadata:
277	[ ("root_identifier", Root_identifier.to_yojson root_identifier)	×
278	]
279	"Loaded persistent root identifier" ;
280	Some root_identifier )	×
281
282	let set_root_state_hash t state_hash = set_root_identifier t { state_hash }	×
283	end
284
285	type t = Factory_type.t
286
287	let create ~logger ~directory ~ledger_depth =
288	{ directory; logger; instance = None; ledger_depth }	×
289
290	let create_instance_exn t =
291	assert (Option.is_none t.instance) ;	×
292	let instance = Instance.create t in
293	t.instance <- Some instance ;	×
294	instance
295
296	let load_from_disk_exn t ~snarked_ledger_hash ~logger =
297	let open Result.Let_syntax in	×
298	assert (Option.is_none t.instance) ;	×
299	let%map instance = Instance.load_from_disk t ~snarked_ledger_hash ~logger in	×
300	t.instance <- Some instance ;	×
301	instance
302
303	let with_instance_exn t ~f =
304	let instance = create_instance_exn t in	×
305	let x = f instance in	×
306	Instance.close instance ; x	×
307
308	let reset_to_genesis_exn t ~precomputed_values =
309	assert (Option.is_none t.instance) ;	×
310	Mina_stdlib_unix.File_system.rmrf t.directory ;
311	with_instance_exn t ~f:(fun instance ->	×
312	ignore	×
313	( Precomputed_values.populate_root precomputed_values	×
314	(Instance.snarked_ledger instance)	×
315	\|> Or_error.map ~f:Ledger.Root.as_unmasked	×
316	: Ledger.Any_ledger.witness Or_error.t ) ;
317	Instance.set_root_identifier instance
318	(genesis_root_identifier
319	~genesis_state_hash:
320	(Precomputed_values.genesis_state_hashes precomputed_values)	×
321	.state_hash ) )	98✔

MinaProtocol / mina / 507

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