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(*
* Copyright (c) 2017-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*)
open! IStd
module L = Logging
exception Error of string
let error ~fatal fmt =
(if fatal then Format.kasprintf (fun err -> raise (Error err)) else L.internal_error) fmt
let check_result_code ?(fatal = false) db ~log rc =
match (rc : Sqlite3.Rc.t) with
| OK | ROW ->
()
| _ as err ->
error ~fatal "%s: %s (%s)" log (Sqlite3.Rc.to_string err) (Sqlite3.errmsg db)
let exec db ~log ~stmt =
(* Call [check_result_code] with [fatal:true] and catch exceptions to rewrite the error message. This avoids allocating the error string when not needed. *)
PerfEvent.log (fun logger ->
PerfEvent.log_begin_event logger ~name:"sql exec" ~arguments:[("stmt", `String log)] () ) ;
let rc = Sqlite3.exec db stmt in
PerfEvent.(log (fun logger -> log_end_event logger ())) ;
try check_result_code ~fatal:true db ~log rc with Error err ->
error ~fatal:true "exec: %s (%s)" err (Sqlite3.errmsg db)
let finalize db ~log stmt =
try check_result_code ~fatal:true db ~log (Sqlite3.finalize stmt) with
| Error err ->
error ~fatal:true "finalize: %s (%s)" err (Sqlite3.errmsg db)
| Sqlite3.Error err ->
error ~fatal:true "finalize: %s: %s (%s)" log err (Sqlite3.errmsg db)
let result_fold_rows ?finalize:(do_finalize = true) db ~log stmt ~init ~f =
let rec aux accum stmt =
match Sqlite3.step stmt with
| Sqlite3.Rc.ROW ->
(* the operation returned a result, get it *)
aux (f accum stmt) stmt
| DONE ->
accum
| err ->
L.die InternalError "%s: %s (%s)" log (Sqlite3.Rc.to_string err) (Sqlite3.errmsg db)
in
if do_finalize then
protect ~finally:(fun () -> finalize db ~log stmt) ~f:(fun () -> aux init stmt)
else aux init stmt
let result_fold_single_column_rows ?finalize db ~log stmt ~init ~f =
result_fold_rows ?finalize db ~log stmt ~init ~f:(fun accum stmt ->
f accum (Sqlite3.column stmt 0) )
let zero_or_one_row ~log = function
| [] ->
None
| [x] ->
Some x
| _ :: _ :: _ as l ->
L.die InternalError "%s: zero or one result expected, got %d rows instead" log
(List.length l)
let result_option ?finalize db ~log ~read_row stmt =
IContainer.rev_map_to_list stmt ~f:read_row ~fold:(result_fold_rows ?finalize db ~log)
|> zero_or_one_row ~log
let result_single_column_option ?finalize db ~log stmt =
Container.to_list stmt ~fold:(result_fold_single_column_rows ?finalize db ~log)
|> zero_or_one_row ~log
let result_unit ?finalize db ~log stmt =
if
not (Container.is_empty stmt ~iter:(Container.iter ~fold:(result_fold_rows ?finalize db ~log)))
then L.die InternalError "%s: the SQLite query should not return any rows" log
let db_close db =
if not (Sqlite3.db_close db) then
raise
(Error
(Printf.sprintf "closing: %s (%s)"
(Sqlite3.errcode db |> Sqlite3.Rc.to_string)
(Sqlite3.errmsg db)))
let with_transaction db ~f =
exec db ~log:"begin transaction" ~stmt:"BEGIN IMMEDIATE TRANSACTION" ;
f () ;
exec db ~log:"commit transaction" ~stmt:"COMMIT"
module type Data = sig
type t
val serialize : t -> Sqlite3.Data.t
val deserialize : Sqlite3.Data.t -> t
end
module MarshalledData (D : sig
type t
end) =
struct
type t = D.t
let deserialize = function[@warning "-8"] Sqlite3.Data.BLOB b -> Marshal.from_string b 0
let serialize x = Sqlite3.Data.BLOB (Marshal.to_string x [])
end