-skeletons for new PG functions

15 files changed, 841 insertions, 132 deletions

diff --git a/src/exchangedb/Makefile.am b/src/exchangedb/Makefile.am
index 01ce13dec..3ea5a0d94 100644
--- a/src/exchangedb/Makefile.am
+++ b/src/exchangedb/Makefile.am
@@ -68,7 +68,9 @@ plugin_LTLIBRARIES = \
 endif
 
 libtaler_plugin_exchangedb_postgres_la_SOURCES = \
-  plugin_exchangedb_postgres.c
+  plugin_exchangedb_postgres.c pg_helper.h \
+  pg_insert_close_request.c pg_insert_close_request.h \
+  pg_insert_reserve_open_deposit.c pg_insert_reserve_open_deposit.h
 libtaler_plugin_exchangedb_postgres_la_LIBADD = \
   $(LTLIBINTL)
 libtaler_plugin_exchangedb_postgres_la_LDFLAGS = \
diff --git a/src/exchangedb/pg_do_reserve_open.c b/src/exchangedb/pg_do_reserve_open.c
new file mode 100644
index 000000000..e4f72845f
--- /dev/null
+++ b/src/exchangedb/pg_do_reserve_open.c
@@ -0,0 +1,68 @@
+/*
+   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_do_reserve_open.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_do_reserve_open.h"
+#include "pg_helper.h"
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_do_reserve_open (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  const struct TALER_Amount *total_paid,
+  uint32_t min_purse_limit,
+  const struct TALER_ReserveSignatureP *reserve_sig,
+  struct GNUNET_TIME_Timestamp desired_expiration,
+  struct GNUNET_TIME_Timestamp now,
+  const struct TALER_Amount *open_fee,
+  struct TALER_Amount *open_cost,
+  const struct GNUNET_TIME_Timestamp *final_expiration)
+{
+  struct PostgresClosure *pg = cls;
+  // FIXME: everything from here is cut&paste
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_auto_from_type (&cpi->coin_pub),
+    GNUNET_PQ_query_param_uint64 (&known_coin_id),
+    GNUNET_PQ_query_param_auto_from_type (coin_sig),
+    GNUNET_PQ_query_param_auto_from_type (reserve_sig),
+    TALER_PQ_query_param_amount (coin_total),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_bool ("insufficient_funds",
+                                insufficient_funds),
+    GNUNET_PQ_result_spec_end
+  };
+
+  PREPARE (pg,
+           "insert_reserve_open_deposit",
+           "SELECT "
+           " insufficient_funds"
+           " FROM exchange_do_reserve_open_deposit"
+           " ($1,$2,$3,$4,$5,$6);");
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "insert_reserve_open_deposit",
+                                                   params,
+                                                   rs);
+}
diff --git a/src/exchangedb/pg_do_reserve_open.h b/src/exchangedb/pg_do_reserve_open.h
new file mode 100644
index 000000000..6e4c91fcd
--- /dev/null
+++ b/src/exchangedb/pg_do_reserve_open.h
@@ -0,0 +1,55 @@
+/*
+   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_do_reserve_open.h
+ * @brief implementation of the do_reserve_open function
+ * @author Christian Grothoff
+ */
+#ifndef PG_DO_RESERVE_OPEN_H
+#define PG_DO_RESERVE_OPEN_H
+
+#include "taler_util.h"
+#include "taler_json_lib.h"
+#include "taler_exchangedb_plugin.h"
+
+
+/**
+ * Insert reserve close operation into database.
+ *
+ * @param cls closure
+ * @param reserve_pub which reserve is this about?
+ * @param execution_date when did we perform the transfer?
+ * @param receiver_account to which account do we transfer, in payto://-format
+ * @param wtid identifier for the wire transfer
+ * @param amount_with_fee amount we charged to the reserve
+ * @param closing_fee how high is the closing fee
+ * @return transaction status code
+ */
+enum GNUNET_DB_QueryStatus
+TEH_PG_do_reserve_open (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  const struct TALER_Amount *total_paid,
+  uint32_t min_purse_limit,
+  const struct TALER_ReserveSignatureP *reserve_sig,
+  struct GNUNET_TIME_Timestamp desired_expiration,
+  struct GNUNET_TIME_Timestamp now,
+  const struct TALER_Amount *open_fee,
+  struct TALER_Amount *open_cost,
+  const struct GNUNET_TIME_Timestamp *final_expiration);
+
+
+#endif
diff --git a/src/exchangedb/pg_helper.h b/src/exchangedb/pg_helper.h
new file mode 100644
index 000000000..e0a4be49d
--- /dev/null
+++ b/src/exchangedb/pg_helper.h
@@ -0,0 +1,149 @@
+/*
+   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_helper.h
+ * @brief shared internal definitions for postgres DB plugin
+ * @author Christian Grothoff
+ */
+#ifndef PG_HELPER_H
+#define PG_HELPER_H
+
+
+/**
+ * Type of the "cls" argument given to each of the functions in
+ * our API.
+ */
+struct PostgresClosure
+{
+
+  /**
+   * Our configuration.
+   */
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * Directory with SQL statements to run to create tables.
+   */
+  char *sql_dir;
+
+  /**
+   * After how long should idle reserves be closed?
+   */
+  struct GNUNET_TIME_Relative idle_reserve_expiration_time;
+
+  /**
+   * After how long should reserves that have seen withdraw operations
+   * be garbage collected?
+   */
+  struct GNUNET_TIME_Relative legal_reserve_expiration_time;
+
+  /**
+   * What delay should we introduce before ready transactions
+   * are actually aggregated?
+   */
+  struct GNUNET_TIME_Relative aggregator_shift;
+
+  /**
+   * Which currency should we assume all amounts to be in?
+   */
+  char *currency;
+
+  /**
+   * Our base URL.
+   */
+  char *exchange_url;
+
+  /**
+   * Postgres connection handle.
+   */
+  struct GNUNET_PQ_Context *conn;
+
+  /**
+   * Name of the current transaction, for debugging.
+   */
+  const char *transaction_name;
+
+  /**
+   * Counts how often we have established a fresh @e conn
+   * to the database. Used to re-prepare statements.
+   */
+  unsigned long long prep_gen;
+
+  /**
+   * Did we initialize the prepared statements
+   * for this session? (To be replaced with @e prep_gen.)
+   */
+  bool init;
+
+};
+
+
+/**
+ * Prepares SQL statement @a sql under @a name for
+ * connection @a pg once.
+ * Returns with #GNUNET_DB_STATUS_HARD_ERROR on failure.
+ *
+ * @param pg a `struct PostgresClosure`
+ * @param name name to prepare the statement under
+ * @param sql actual SQL text
+ */
+#define PREPARE(pg,name,sql)                      \
+  do {                                            \
+    static unsigned long long prep_cnt;           \
+                                                  \
+    if (prep_cnt < pg->prep_gen)                  \
+    {                                             \
+      struct GNUNET_PQ_PreparedStatement ps[] = { \
+        GNUNET_PQ_make_prepare (name, sql, 0),    \
+        GNUNET_PQ_PREPARED_STATEMENT_END          \
+      };                                          \
+                                                  \
+      if (GNUNET_OK !=                            \
+          GNUNET_PQ_prepare_statements (pg->conn, \
+                                        ps))      \
+      {                                           \
+        GNUNET_break (0);                         \
+        return GNUNET_DB_STATUS_HARD_ERROR;       \
+      }                                           \
+      prep_cnt = pg->prep_gen;                    \
+    }                                             \
+  } while (0)
+
+
+/**
+ * Wrapper macro to add the currency from the plugin's state
+ * when fetching amounts from the database.
+ *
+ * @param field name of the database field to fetch amount from
+ * @param[out] amountp pointer to amount to set
+ */
+#define TALER_PQ_RESULT_SPEC_AMOUNT(field,amountp) TALER_PQ_result_spec_amount ( \
+    field,pg->currency,amountp)
+
+
+/**
+ * Wrapper macro to add the currency from the plugin's state
+ * when fetching amounts from the database.  NBO variant.
+ *
+ * @param field name of the database field to fetch amount from
+ * @param[out] amountp pointer to amount to set
+ */
+#define TALER_PQ_RESULT_SPEC_AMOUNT_NBO(field,                          \
+                                        amountp) TALER_PQ_result_spec_amount_nbo ( \
+    field,pg->currency,amountp)
+
+
+#endif
diff --git a/src/exchangedb/pg_insert_close_request.c b/src/exchangedb/pg_insert_close_request.c
new file mode 100644
index 000000000..3622149a7
--- /dev/null
+++ b/src/exchangedb/pg_insert_close_request.c
@@ -0,0 +1,64 @@
+/*
+   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_insert_close_request.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_insert_close_request.h"
+#include "pg_helper.h"
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_insert_close_request (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  const char *payto_uri,
+  const struct TALER_ReserveSignatureP *reserve_sig,
+  struct GNUNET_TIME_Timestamp request_timestamp,
+  const struct TALER_Amount *closing_fee,
+  struct TALER_Amount *final_balance)
+{
+  struct PostgresClosure *pg = cls;
+  // FIXME: deal with payto_uri and closing_fee!!
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_auto_from_type (reserve_pub),
+    GNUNET_PQ_query_param_timestamp (&request_timestamp),
+    GNUNET_PQ_query_param_auto_from_type (reserve_sig),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    TALER_PQ_RESULT_SPEC_AMOUNT ("out_final_balance",
+                                 final_balance),
+    GNUNET_PQ_result_spec_end
+  };
+
+  PREPARE (pg,
+           "call_account_close",
+           "SELECT "
+           " out_final_balance_val"
+           ",out_final_balance_frac"
+           " FROM exchange_do_close_request"
+           "  ($1, $2, $3)");
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "call_account_close",
+                                                   params,
+                                                   rs);
+}
diff --git a/src/exchangedb/pg_insert_close_request.h b/src/exchangedb/pg_insert_close_request.h
new file mode 100644
index 000000000..09404094f
--- /dev/null
+++ b/src/exchangedb/pg_insert_close_request.h
@@ -0,0 +1,52 @@
+/*
+   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_insert_close_request.h
+ * @brief implementation of the insert_close_request function
+ * @author Christian Grothoff
+ */
+#ifndef PG_INSERT_CLOSE_REQUEST_H
+#define PG_INSERT_CLOSE_REQUEST_H
+
+#include "taler_util.h"
+#include "taler_json_lib.h"
+#include "taler_exchangedb_plugin.h"
+
+
+/**
+ * Function called to initiate closure of an account.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param reserve_pub public key of the account to close
+ * @param payto_uri where to wire the funds
+ * @param reserve_sig signature affiming that the account is to be closed
+ * @param request_timestamp time of the close request (client-side?)
+ * @param closing_fee closing fee to charge
+ * @param[out] final_balance set to the final balance in the account that will be wired back to the origin account
+ * @return transaction status code
+ */
+enum GNUNET_DB_QueryStatus
+TEH_PG_insert_close_request (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  const char *payto_uri,
+  const struct TALER_ReserveSignatureP *reserve_sig,
+  struct GNUNET_TIME_Timestamp request_timestamp,
+  const struct TALER_Amount *closing_fee,
+  struct TALER_Amount *final_balance);
+
+
+#endif
diff --git a/src/exchangedb/pg_insert_reserve_open_deposit.c b/src/exchangedb/pg_insert_reserve_open_deposit.c
new file mode 100644
index 000000000..c767bfeee
--- /dev/null
+++ b/src/exchangedb/pg_insert_reserve_open_deposit.c
@@ -0,0 +1,64 @@
+/*
+   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_insert_reserve_open_deposit.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_insert_reserve_open_deposit.h"
+#include "pg_helper.h"
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_insert_reserve_open_deposit (
+  void *cls,
+  const struct TALER_CoinPublicInfo *cpi,
+  const struct TALER_CoinSpendSignatureP *coin_sig,
+  uint64_t known_coin_id,
+  const struct TALER_Amount *coin_total,
+  const struct TALER_ReserveSignatureP *reserve_sig,
+  bool *insufficient_funds)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_auto_from_type (&cpi->coin_pub),
+    GNUNET_PQ_query_param_uint64 (&known_coin_id),
+    GNUNET_PQ_query_param_auto_from_type (coin_sig),
+    GNUNET_PQ_query_param_auto_from_type (reserve_sig),
+    TALER_PQ_query_param_amount (coin_total),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_bool ("insufficient_funds",
+                                insufficient_funds),
+    GNUNET_PQ_result_spec_end
+  };
+
+  PREPARE (pg,
+           "insert_reserve_open_deposit",
+           "SELECT "
+           " insufficient_funds"
+           " FROM exchange_do_reserve_open_deposit"
+           " ($1,$2,$3,$4,$5,$6);");
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "insert_reserve_open_deposit",
+                                                   params,
+                                                   rs);
+}
diff --git a/src/exchangedb/pg_insert_reserve_open_deposit.h b/src/exchangedb/pg_insert_reserve_open_deposit.h
new file mode 100644
index 000000000..335fda52d
--- /dev/null
+++ b/src/exchangedb/pg_insert_reserve_open_deposit.h
@@ -0,0 +1,52 @@
+/*
+   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_insert_reserve_open_deposit.h
+ * @brief implementation of the insert_reserve_open_deposit function
+ * @author Christian Grothoff
+ */
+#ifndef PG_INSERT_RESERVE_OPEN_DEPOSIT_H
+#define PG_INSERT_RESERVE_OPEN_DEPOSIT_H
+
+#include "taler_util.h"
+#include "taler_json_lib.h"
+#include "taler_exchangedb_plugin.h"
+
+
+/**
+ * Insert reserve open coin deposit data into database.
+ * Subtracts the @a coin_total from the coin's balance.
+ *
+ * @param cls closure
+ * @param cpi public information about the coin
+ * @param coin_sig signature with @e coin_pub of type #TALER_SIGNATURE_WALLET_RESERVE_OPEN_DEPOSIT
+ * @param known_coin_id ID of the coin in the known_coins table
+ * @param coin_total amount to be spent of the coin (including deposit fee)
+ * @param reserve_sig signature by the reserve affirming the open operation
+ * @param[out] insufficient_funds set to true if the coin's balance is insufficient, otherwise to false
+ * @return transaction status code, 0 if operation is already in the DB
+ */
+enum GNUNET_DB_QueryStatus
+TEH_PG_insert_reserve_open_deposit (
+  void *cls,
+  const struct TALER_CoinPublicInfo *cpi,
+  const struct TALER_CoinSpendSignatureP *coin_sig,
+  uint64_t known_coin_id,
+  const struct TALER_Amount *coin_total,
+  const struct TALER_ReserveSignatureP *reserve_sig,
+  bool *insufficient_funds);
+
+#endif
diff --git a/src/exchangedb/pg_iterate_kyc_reference.c b/src/exchangedb/pg_iterate_kyc_reference.c
new file mode 100644
index 000000000..e24a22bf2
--- /dev/null
+++ b/src/exchangedb/pg_iterate_kyc_reference.c
@@ -0,0 +1,58 @@
+/*
+   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_iterate_kyc_reference.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_iterate_kyc_reference.h"
+#include "pg_helper.h"
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_iterate_kyc_reference (
+  void *cls,
+  const struct TALER_PaytoHashP *h_payto,
+  TALER_EXCHANGEDB_LegitimizationProcessCallback lpc,
+  void *lpc_cls)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_auto_from_type (h_payto),
+    GNUNET_PQ_query_param_end
+  };
+  // FIXME: everything from here is copy*paste
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_bool ("insufficient_funds",
+                                insufficient_funds),
+    GNUNET_PQ_result_spec_end
+  };
+
+  PREPARE (pg,
+           "iterate_kyc_reference",
+           "SELECT "
+           " insufficient_funds"
+           " FROM exchange_do_reserve_open_deposit"
+           " ($1,$2,$3,$4,$5,$6);");
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "iterate_kyc_reference",
+                                                   params,
+                                                   rs);
+}
diff --git a/src/exchangedb/pg_iterate_kyc_reference.h b/src/exchangedb/pg_iterate_kyc_reference.h
new file mode 100644
index 000000000..0242fdcf1
--- /dev/null
+++ b/src/exchangedb/pg_iterate_kyc_reference.h
@@ -0,0 +1,46 @@
+/*
+   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_iterate_kyc_reference.h
+ * @brief implementation of the iterate_kyc_reference function
+ * @author Christian Grothoff
+ */
+#ifndef PG_ITERATE_KYC_REFERENCE_H
+#define PG_ITERATE_KYC_REFERENCE_H
+
+#include "taler_util.h"
+#include "taler_json_lib.h"
+#include "taler_exchangedb_plugin.h"
+
+
+/**
+ * Call us on KYC legitimization processes satisfied and not expired for the
+ * given account.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param h_payto account identifier
+ * @param lpc function to call for each satisfied KYC legitimization process
+ * @param lpc_cls closure for @a lpc
+ * @return transaction status code
+ */
+enum GNUNET_DB_QueryStatus
+TEH_PG_iterate_kyc_reference (
+  void *cls,
+  const struct TALER_PaytoHashP *h_payto,
+  TALER_EXCHANGEDB_LegitimizationProcessCallback lpc,
+  void *lpc_cls);
+
+#endif
diff --git a/src/exchangedb/pg_iterate_reserve_close_info.c b/src/exchangedb/pg_iterate_reserve_close_info.c
new file mode 100644
index 000000000..e9a5f6648
--- /dev/null
+++ b/src/exchangedb/pg_iterate_reserve_close_info.c
@@ -0,0 +1,63 @@
+/*
+   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_iterate_reserve_close_info.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_insert_reserve_open_deposit.h"
+#include "pg_helper.h"
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_iterate_reserve_close_info (
+  void *cls,
+  const struct TALER_PaytoHashP *h_payto,
+  struct GNUNET_TIME_Absolute time_limit,
+  TALER_EXCHANGEDB_KycAmountCallback kac,
+  void *kac_cls)
+{
+  struct PostgresClosure *pg = cls;
+  // FIXME: everything from here is copy&paste
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_auto_from_type (&cpi->coin_pub),
+    GNUNET_PQ_query_param_uint64 (&known_coin_id),
+    GNUNET_PQ_query_param_auto_from_type (coin_sig),
+    GNUNET_PQ_query_param_auto_from_type (reserve_sig),
+    TALER_PQ_query_param_amount (coin_total),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_bool ("insufficient_funds",
+                                insufficient_funds),
+    GNUNET_PQ_result_spec_end
+  };
+
+  PREPARE (pg,
+           "insert_reserve_open_deposit",
+           "SELECT "
+           " insufficient_funds"
+           " FROM exchange_do_reserve_open_deposit"
+           " ($1,$2,$3,$4,$5,$6);");
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "insert_reserve_open_deposit",
+                                                   params,
+                                                   rs);
+}
diff --git a/src/exchangedb/pg_iterate_reserve_close_info.h b/src/exchangedb/pg_iterate_reserve_close_info.h
new file mode 100644
index 000000000..a7e7c8d4a
--- /dev/null
+++ b/src/exchangedb/pg_iterate_reserve_close_info.h
@@ -0,0 +1,50 @@
+/*
+   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_iterate_reserve_close_info.h
+ * @brief implementation of the iterate_reserve_close_info function
+ * @author Christian Grothoff
+ */
+#ifndef PG_ITERATE_RESERVE_CLOSE_INFO_H
+#define PG_ITERATE_RESERVE_CLOSE_INFO_H
+
+#include "taler_util.h"
+#include "taler_json_lib.h"
+#include "taler_exchangedb_plugin.h"
+
+
+/**
+ * Select information needed for KYC checks on reserve close: historic
+ * reserve closures going to the same account.
+ *
+ * @param cls closure
+ * @param h_payto which target account is this about?
+ * @param h_payto account identifier
+ * @param time_limit oldest transaction that could be relevant
+ * @param kac function to call for each applicable amount, in reverse chronological order (or until @a kac aborts by returning anything except #GNUNET_OK).
+ * @param kac_cls closure for @a kac
+ * @return transaction status code, @a kac aborting with #GNUNET_NO is not an error
+ */
+enum GNUNET_DB_QueryStatus
+TEH_PG_iterate_reserve_close_info (
+  void *cls,
+  const struct TALER_PaytoHashP *h_payto,
+  struct GNUNET_TIME_Absolute time_limit,
+  TALER_EXCHANGEDB_KycAmountCallback kac,
+  void *kac_cls);
+
+
+#endif
diff --git a/src/exchangedb/pg_select_reserve_close_info.c b/src/exchangedb/pg_select_reserve_close_info.c
new file mode 100644
index 000000000..472ec27c9
--- /dev/null
+++ b/src/exchangedb/pg_select_reserve_close_info.c
@@ -0,0 +1,62 @@
+/*
+   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_select_reserve_close_info.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_insert_reserve_open_deposit.h"
+#include "pg_helper.h"
+
+
+enum GNUNET_DB_QueryStatus
+TEH_PG_select_reserve_close_info (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  struct TALER_Amount *balance,
+  char **payto_uri)
+{
+  struct PostgresClosure *pg = cls;
+  // FIXME: everything from here is copy*paste!
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_auto_from_type (&cpi->coin_pub),
+    GNUNET_PQ_query_param_uint64 (&known_coin_id),
+    GNUNET_PQ_query_param_auto_from_type (coin_sig),
+    GNUNET_PQ_query_param_auto_from_type (reserve_sig),
+    TALER_PQ_query_param_amount (coin_total),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_bool ("insufficient_funds",
+                                insufficient_funds),
+    GNUNET_PQ_result_spec_end
+  };
+
+  PREPARE (pg,
+           "insert_reserve_open_deposit",
+           "SELECT "
+           " insufficient_funds"
+           " FROM exchange_do_reserve_open_deposit"
+           " ($1,$2,$3,$4,$5,$6);");
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "insert_reserve_open_deposit",
+                                                   params,
+                                                   rs);
+}
diff --git a/src/exchangedb/pg_select_reserve_close_info.h b/src/exchangedb/pg_select_reserve_close_info.h
new file mode 100644
index 000000000..2b90ffd05
--- /dev/null
+++ b/src/exchangedb/pg_select_reserve_close_info.h
@@ -0,0 +1,49 @@
+/*
+   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_select_reserve_close_info.h
+ * @brief implementation of the select_reserve_close_info function
+ * @author Christian Grothoff
+ */
+#ifndef PG_SELECT_RESERVE_CLOSE_INFO_H
+#define PG_SELECT_RESERVE_CLOSE_INFO_H
+
+#include "taler_util.h"
+#include "taler_json_lib.h"
+#include "taler_exchangedb_plugin.h"
+
+
+/**
+ * Select information needed to see if we can close
+ * a reserve.
+ *
+ * @param cls closure
+ * @param reserve_pub which reserve is this about?
+ * @param[out] balance current reserve balance
+ * @param[out] payto_uri set to URL of account that
+ *             originally funded the reserve;
+ *             could be set to NULL if not known
+ * @return transaction status code, 0 if reserve unknown
+ */
+enum GNUNET_DB_QueryStatus
+TEH_PG_select_reserve_close_info (
+  void *cls,
+  const struct TALER_ReservePublicKeyP *reserve_pub,
+  struct TALER_Amount *balance,
+  char **payto_uri);
+
+
+#endif
diff --git a/src/exchangedb/plugin_exchangedb_postgres.c b/src/exchangedb/plugin_exchangedb_postgres.c
index e3da5216b..341364f9f 100644
--- a/src/exchangedb/plugin_exchangedb_postgres.c
+++ b/src/exchangedb/plugin_exchangedb_postgres.c
@@ -29,6 +29,9 @@
 #include "taler_util.h"
 #include "taler_json_lib.h"
 #include "taler_exchangedb_plugin.h"
+#include "pg_helper.h"
+#include "pg_insert_close_request.h"
+#include "pg_insert_reserve_open_deposit.h"
 #include <poll.h>
 #include <pthread.h>
 #include <libpq-fe.h>
@@ -42,26 +45,6 @@
  */
 #define AUTO_EXPLAIN 1
 
-/**
- * Wrapper macro to add the currency from the plugin's state
- * when fetching amounts from the database.
- *
- * @param field name of the database field to fetch amount from
- * @param[out] amountp pointer to amount to set
- */
-#define TALER_PQ_RESULT_SPEC_AMOUNT(field,amountp) TALER_PQ_result_spec_amount ( \
-    field,pg->currency,amountp)
-
-/**
- * Wrapper macro to add the currency from the plugin's state
- * when fetching amounts from the database.  NBO variant.
- *
- * @param field name of the database field to fetch amount from
- * @param[out] amountp pointer to amount to set
- */
-#define TALER_PQ_RESULT_SPEC_AMOUNT_NBO(field,                          \
-                                        amountp) TALER_PQ_result_spec_amount_nbo ( \
-    field,pg->currency,amountp)
 
 /**
  * Log a really unexpected PQ error with all the details we can get hold of.
@@ -82,69 +65,6 @@
 
 
 /**
- * Type of the "cls" argument given to each of the functions in
- * our API.
- */
-struct PostgresClosure
-{
-
-  /**
-   * Our configuration.
-   */
-  const struct GNUNET_CONFIGURATION_Handle *cfg;
-
-  /**
-   * Directory with SQL statements to run to create tables.
-   */
-  char *sql_dir;
-
-  /**
-   * After how long should idle reserves be closed?
-   */
-  struct GNUNET_TIME_Relative idle_reserve_expiration_time;
-
-  /**
-   * After how long should reserves that have seen withdraw operations
-   * be garbage collected?
-   */
-  struct GNUNET_TIME_Relative legal_reserve_expiration_time;
-
-  /**
-   * What delay should we introduce before ready transactions
-   * are actually aggregated?
-   */
-  struct GNUNET_TIME_Relative aggregator_shift;
-
-  /**
-   * Which currency should we assume all amounts to be in?
-   */
-  char *currency;
-
-  /**
-   * Our base URL.
-   */
-  char *exchange_url;
-
-  /**
-   * Postgres connection handle.
-   */
-  struct GNUNET_PQ_Context *conn;
-
-  /**
-   * Name of the current transaction, for debugging.
-   */
-  const char *transaction_name;
-
-  /**
-   * Did we initialize the prepared statements
-   * for this session?
-   */
-  bool init;
-
-};
-
-
-/**
  * Drop all Taler tables.  This should only be used by testcases.
  *
  * @param cls the `struct PostgresClosure` with the plugin-specific state
@@ -4467,15 +4387,7 @@ prepare_statements (struct PostgresClosure *pg)
       " FROM exchange_do_history_request"
       "  ($1, $2, $3, $4, $5)",
       5),
-    /* Used in #postgres_insert_close_request() */
-    GNUNET_PQ_make_prepare (
-      "call_account_close",
-      "SELECT "
-      " out_final_balance_val"
-      ",out_final_balance_frac"
-      " FROM exchange_do_close_request"
-      "  ($1, $2, $3)",
-      3),
+
     /* Used in #postgres_insert_kyc_requirement_for_account() */
     GNUNET_PQ_make_prepare (
       "insert_legitimization_requirement",
@@ -4674,6 +4586,7 @@ internal_setup (struct PostgresClosure *pg,
                                           NULL);
     if (NULL == db_conn)
       return GNUNET_SYSERR;
+    pg->prep_gen++;
     pg->conn = db_conn;
   }
   if (NULL == pg->transaction_name)
@@ -16237,44 +16150,6 @@ postgres_insert_history_request (
 
 
 /**
- * Function called to initiate closure of an account.
- *
- * @param cls the @e cls of this struct with the plugin-specific state
- * @param reserve_pub public key of the account to close
- * @param reserve_sig signature affiming that the account is to be closed
- * @param request_timestamp time of the close request (client-side?)
- * @param[out] final_balance set to the final balance in the account that will be wired back to the origin account
- * @return transaction status code
- */
-static enum GNUNET_DB_QueryStatus
-postgres_insert_close_request (
-  void *cls,
-  const struct TALER_ReservePublicKeyP *reserve_pub,
-  const struct TALER_ReserveSignatureP *reserve_sig,
-  struct GNUNET_TIME_Timestamp request_timestamp,
-  struct TALER_Amount *final_balance)
-{
-  struct PostgresClosure *pg = cls;
-  struct GNUNET_PQ_QueryParam params[] = {
-    GNUNET_PQ_query_param_auto_from_type (reserve_pub),
-    GNUNET_PQ_query_param_timestamp (&request_timestamp),
-    GNUNET_PQ_query_param_auto_from_type (reserve_sig),
-    GNUNET_PQ_query_param_end
-  };
-  struct GNUNET_PQ_ResultSpec rs[] = {
-    TALER_PQ_RESULT_SPEC_AMOUNT ("out_final_balance",
-                                 final_balance),
-    GNUNET_PQ_result_spec_end
-  };
-
-  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
-                                                   "call_account_close",
-                                                   params,
-                                                   rs);
-}
-
-
-/**
  * Function called to persist a request to drain profits.
  *
  * @param cls the @e cls of this struct with the plugin-specific state
@@ -17390,7 +17265,7 @@ libtaler_plugin_exchangedb_postgres_init (void *cls)
   plugin->insert_history_request
     = &postgres_insert_history_request;
   plugin->insert_close_request
-    = &postgres_insert_close_request;
+    = &TEH_PG_insert_close_request;
   plugin->insert_drain_profit
     = &postgres_insert_drain_profit;
   plugin->profit_drains_get_pending