1 files changed, 174 insertions, 0 deletions
diff --git a/src/exchangedb/pg_get_expired_reserves.c b/src/exchangedb/pg_get_expired_reserves.c
new file mode 100644
index 000000000..be9ece98a
--- /dev/null
+++ b/src/exchangedb/pg_get_expired_reserves.c
@@ -0,0 +1,174 @@
+/*
+   This file is part of TALER
+   Copyright (C) 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/>
+ */
+/**
+ * @file pg_get_expired_reserves.c
+ * @brief Low-level (statement-level) Postgres database access for the exchange
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "taler_error_codes.h"
+#include "taler_dbevents.h"
+#include "taler_pq_lib.h"
+#include "pg_get_expired_reserves.h"
+#include "pg_helper.h"
+
+
+/**
+ * Closure for #reserve_expired_cb().
+ */
+struct ExpiredReserveContext
+{
+  /**
+   * Function to call for each expired reserve.
+   */
+  TALER_EXCHANGEDB_ReserveExpiredCallback rec;
+
+  /**
+   * Closure to give to @e rec.
+   */
+  void *rec_cls;
+
+  /**
+   * Plugin context.
+   */
+  struct PostgresClosure *pg;
+
+  /**
+   * Set to #GNUNET_SYSERR on error.
+   */
+  enum GNUNET_GenericReturnValue status;
+};
+
+
+/**
+ * Function to be called with the results of a SELECT statement
+ * that has returned @a num_results results.
+ *
+ * @param cls closure
+ * @param result the postgres result
+ * @param num_results the number of results in @a result
+ */
+static void
+reserve_expired_cb (void *cls,
+                    PGresult *result,
+                    unsigned int num_results)
+{
+  struct ExpiredReserveContext *erc = cls;
+  struct PostgresClosure *pg = erc->pg;
+  enum GNUNET_GenericReturnValue ret;
+
+  ret = GNUNET_OK;
+  for (unsigned int i = 0; i<num_results; i++)
+  {
+    struct GNUNET_TIME_Timestamp exp_date;
+    char *account_details;
+    struct TALER_ReservePublicKeyP reserve_pub;
+    struct TALER_Amount remaining_balance;
+    struct GNUNET_PQ_ResultSpec rs[] = {
+      GNUNET_PQ_result_spec_timestamp ("expiration_date",
+                                       &exp_date),
+      GNUNET_PQ_result_spec_string ("account_details",
+                                    &account_details),
+      GNUNET_PQ_result_spec_auto_from_type ("reserve_pub",
+                                            &reserve_pub),
+      TALER_PQ_result_spec_amount ("current_balance",
+                                   pg->currency,
+                                   &remaining_balance),
+      GNUNET_PQ_result_spec_end
+    };
+
+    if (GNUNET_OK !=
+        GNUNET_PQ_extract_result (result,
+                                  rs,
+                                  i))
+    {
+      GNUNET_break (0);
+      ret = GNUNET_SYSERR;
+      break;
+    }
+    ret = erc->rec (erc->rec_cls,
+                    &reserve_pub,
+                    &remaining_balance,
+                    account_details,
+                    exp_date,
+                    0);
+    GNUNET_PQ_cleanup_result (rs);
+    if (GNUNET_OK != ret)
+      break;
+  }
+  erc->status = ret;
+}
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_get_expired_reserves (void *cls,
+                             struct GNUNET_TIME_Timestamp now,
+                             TALER_EXCHANGEDB_ReserveExpiredCallback rec,
+                             void *rec_cls)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_timestamp (&now),
+    GNUNET_PQ_query_param_end
+  };
+  struct ExpiredReserveContext ectx = {
+    .rec = rec,
+    .rec_cls = rec_cls,
+    .pg = pg,
+    .status = GNUNET_OK
+  };
+  enum GNUNET_DB_QueryStatus qs;
+
+  PREPARE (pg,
+           "get_expired_reserves",
+           "WITH ed AS MATERIALIZED ( "
+           " SELECT * "
+           " FROM reserves "
+           " WHERE expiration_date <= $1 "
+           "   AND ((current_balance).val != 0 OR (current_balance).frac != 0) "
+           " ORDER BY expiration_date ASC "
+           " LIMIT 1 "
+           ") "
+           "SELECT "
+           " ed.expiration_date "
+           " ,payto_uri AS account_details "
+           " ,ed.reserve_pub "
+           " ,current_balance "
+           "FROM ( "
+           " SELECT "
+           "  * "
+           " FROM reserves_in "
+           " WHERE reserve_pub = ( "
+           "     SELECT reserve_pub FROM ed) "
+           " ) ri "
+           "JOIN wire_targets wt ON (ri.wire_source_h_payto = wt.wire_target_h_payto) "
+           "JOIN ed ON (ri.reserve_pub = ed.reserve_pub);");
+  qs = GNUNET_PQ_eval_prepared_multi_select (pg->conn,
+                                             "get_expired_reserves",
+                                             params,
+                                             &reserve_expired_cb,
+                                             &ectx);
+  switch (ectx.status)
+  {
+  case GNUNET_SYSERR:
+    return GNUNET_DB_STATUS_HARD_ERROR;
+  case GNUNET_NO:
+    return GNUNET_DB_STATUS_SOFT_ERROR;
+  case GNUNET_OK:
+    break;
+  }
+  return qs;
+}