cp sql/ from GNU Taler exchange

include/sql/exchange_do_reserve_open_deposit.sql

@@ -0,0 +1,84 @@
+--
+-- This file is part of TALER
+-- Copyright (C) 2014--2022 Taler Systems SA
+--
+-- TALER is free software; you can redistribute it and/or modify it under the
+-- terms of the GNU General Public License as published by the Free Software
+-- Foundation; either version 3, or (at your option) any later version.
+--
+-- TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+-- WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+-- A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License along with
+-- TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+--
+
+
+CREATE OR REPLACE FUNCTION exchange_do_reserve_open_deposit(
+  IN in_coin_pub BYTEA,
+  IN in_known_coin_id INT8,
+  IN in_coin_sig BYTEA,
+  IN in_reserve_sig BYTEA,
+  IN in_reserve_pub BYTEA,
+  IN in_coin_total taler_amount,
+  OUT out_insufficient_funds BOOLEAN)
+LANGUAGE plpgsql
+AS $$
+BEGIN
+
+INSERT INTO exchange.reserves_open_deposits
+  (reserve_sig
+  ,reserve_pub
+  ,coin_pub
+  ,coin_sig
+  ,contribution
+  )
+  VALUES
+  (in_reserve_sig
+  ,in_reserve_pub
+  ,in_coin_pub
+  ,in_coin_sig
+  ,in_coin_total
+  )
+  ON CONFLICT DO NOTHING;
+
+IF NOT FOUND
+THEN
+  -- Idempotent request known, return success.
+  out_insufficient_funds=FALSE;
+  RETURN;
+END IF;
+
+
+-- Check and update balance of the coin.
+UPDATE exchange.known_coins kc
+  SET
+    remaining.frac=(kc.remaining).frac-in_coin_total.frac
+       + CASE
+         WHEN (kc.remaining).frac < in_coin_total.frac
+         THEN 100000000
+         ELSE 0
+         END,
+    remaining.val=(kc.remaining).val-in_coin_total.val
+       - CASE
+         WHEN (kc.remaining).frac < in_coin_total.frac
+         THEN 1
+         ELSE 0
+         END
+  WHERE coin_pub=in_coin_pub
+    AND ( ((kc.remaining).val > in_coin_total.val) OR
+          ( ((kc.remaining).frac >= in_coin_total.frac) AND
+            ((kc.remaining).val >= in_coin_total.val) ) );
+
+IF NOT FOUND
+THEN
+  -- Insufficient balance.
+  out_insufficient_funds=TRUE;
+  RETURN;
+END IF;
+
+-- Everything fine, return success!
+out_insufficient_funds=FALSE;
+
+END $$;