clean up tipping transactiton mess a bit (wip)

9 files changed, 303 insertions, 294 deletions

diff --git a/src/backend/taler-merchant-httpd_pay.c b/src/backend/taler-merchant-httpd_pay.c
index cb8ef8bf..96dbdc02 100644
--- a/src/backend/taler-merchant-httpd_pay.c
+++ b/src/backend/taler-merchant-httpd_pay.c
@@ -1781,8 +1781,8 @@ begin_transaction (struct PayContext *pc)
       db->rollback (db->cls);
       if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
       {
-	begin_transaction (pc);
-	return;
+        begin_transaction (pc);
+        return;
       }
       /* Always report on hard error as well to enable diagnostics */
       GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
@@ -1816,8 +1816,8 @@ begin_transaction (struct PayContext *pc)
       db->rollback (db->cls);
       if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
       {
-	begin_transaction (pc);
-	return;
+        begin_transaction (pc);
+        return;
       }
       /* Always report on hard error as well to enable diagnostics */
       GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
diff --git a/src/backend/taler-merchant-httpd_refund.c b/src/backend/taler-merchant-httpd_refund.c
index 75f6ed91..fbf72f16 100644
--- a/src/backend/taler-merchant-httpd_refund.c
+++ b/src/backend/taler-merchant-httpd_refund.c
@@ -130,6 +130,7 @@ MH_handler_refund_increase (struct TMH_RequestHandler *rh,
     GNUNET_JSON_spec_end ()
   };
   enum GNUNET_DB_QueryStatus qs;
+  enum GNUNET_DB_QueryStatus qsx;
 
   if (NULL == *connection_cls)
   {
@@ -178,17 +179,17 @@ MH_handler_refund_increase (struct TMH_RequestHandler *rh,
     GNUNET_JSON_parse_free (spec);
     return TMH_RESPONSE_reply_not_found (connection,
                                          TALER_EC_REFUND_INSTANCE_UNKNOWN,
-					 "Unknown instance given");
+                                         "Unknown instance given");
   }
 
   db->preflight (db->cls);
 
   /* Convert order id to h_contract_terms */
   qs = db->find_contract_terms (db->cls,
-				&contract_terms,
+                                &contract_terms,
                                 &last_session_id,
-				order_id,
-				&mi->pubkey);
+                                order_id,
+                                &mi->pubkey);
   if (0 > qs)
   {
     /* single, read-only SQL statements should never cause
@@ -226,12 +227,46 @@ MH_handler_refund_increase (struct TMH_RequestHandler *rh,
   }
   for (unsigned int i=0;i<MAX_RETRIES;i++)
   {
+    if (GNUNET_OK !=
+        db->start (db->cls,
+                   "increase refund"))
+    {
+      GNUNET_break (0);
+      return GNUNET_DB_STATUS_HARD_ERROR;
+    }
     qs = db->increase_refund_for_contract (db->cls,
-					   &h_contract_terms,
-					   &mi->pubkey,
-					   &refund,
-					   reason);
-    if (GNUNET_DB_STATUS_SOFT_ERROR != qs)
+                                           &h_contract_terms,
+                                           &mi->pubkey,
+                                           &refund,
+                                           reason);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "increase refund returned %d\n",
+                qs);
+    if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+    {
+      GNUNET_break (0);
+      db->rollback (db->cls);
+      break;
+    }
+    if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
+    {
+      db->rollback (db->cls);
+      continue;
+    }
+    /* Got one or more deposits */
+    if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != qs)
+    {
+      db->rollback (db->cls);
+      break;
+    }
+    qsx = db->commit (db->cls);
+    if (GNUNET_DB_STATUS_HARD_ERROR == qsx)
+    {
+      GNUNET_break (0);
+      qs = qsx;
+      break;
+    }
+    if (GNUNET_DB_STATUS_SOFT_ERROR != qsx)
       break;
   }
   if (0 > qs)
@@ -265,7 +300,6 @@ MH_handler_refund_increase (struct TMH_RequestHandler *rh,
    * Just a "200 OK" should be fine here, as the frontend has all
    * the information needed to generate the right response.
    */
-
   confirmation.purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_REFUND_OK);
   confirmation.purpose.size = htonl (sizeof (struct TALER_MerchantRefundConfirmationPS));
   GNUNET_CRYPTO_hash (order_id,
@@ -465,10 +499,10 @@ MH_handler_refund_lookup (struct TMH_RequestHandler *rh,
   /* Convert order id to h_contract_terms */
   contract_terms = NULL;
   qs = db->find_contract_terms (db->cls,
-				&contract_terms,
+                                &contract_terms,
                                 &last_session_id,
-				order_id,
-				&mi->pubkey);
+                                order_id,
+                                &mi->pubkey);
   if (0 > qs)
   {
     /* single, read-only SQL statements should never cause
@@ -554,13 +588,14 @@ TM_get_refund_json (const struct MerchantInstance *mi,
   prd.h_contract_terms = h_contract_terms;
   prd.merchant = mi;
   prd.ec = TALER_EC_NONE;
+  db->preflight (db->cls);
   for (unsigned int i=0;i<MAX_RETRIES;i++)
   {
     qs = db->get_refunds_from_contract_terms_hash (db->cls,
-						   &mi->pubkey,
-						   h_contract_terms,
-						   &process_refunds_cb,
-						   &prd);
+                                                   &mi->pubkey,
+                                                   h_contract_terms,
+                                                   &process_refunds_cb,
+                                                   &prd);
     if (GNUNET_DB_STATUS_SOFT_ERROR != qs)
       break;
   }
diff --git a/src/backend/taler-merchant-httpd_tip-authorize.c b/src/backend/taler-merchant-httpd_tip-authorize.c
index 58ee405c..9301df92 100644
--- a/src/backend/taler-merchant-httpd_tip-authorize.c
+++ b/src/backend/taler-merchant-httpd_tip-authorize.c
@@ -202,11 +202,11 @@ handle_status (void *cls,
         GNUNET_CRYPTO_hash (history[i].details.in_details.wire_reference,
                             history[i].details.in_details.wire_reference_size,
                             &uuid);
-        qs = db->enable_tip_reserve (db->cls,
-                                     &tac->reserve_priv,
-                                     &uuid,
-                                     &history[i].amount,
-                                     expiration);
+        qs = db->enable_tip_reserve_TR (db->cls,
+                                        &tac->reserve_priv,
+                                        &uuid,
+                                        &history[i].amount,
+                                        expiration);
         if (0 > qs)
         {
           GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
@@ -377,14 +377,13 @@ MH_handler_tip_authorize (struct TMH_RequestHandler *rh,
 					 "exchange for tipping not configured for the instance");
   }
   tac->reserve_priv = mi->tip_reserve;
-  db->preflight (db->cls);
-  ec = db->authorize_tip (db->cls,
-                          tac->justification,
-                          &tac->amount,
-                          &mi->tip_reserve,
-			  mi->tip_exchange,
-                          &expiration,
-                          &tip_id);
+  ec = db->authorize_tip_TR (db->cls,
+                             tac->justification,
+                             &tac->amount,
+                             &mi->tip_reserve,
+                             mi->tip_exchange,
+                             &expiration,
+                             &tip_id);
   /* If we have insufficient funds according to OUR database,
      check with exchange to see if the reserve has been topped up
      in the meantime (or if tips were not withdrawn yet). */
diff --git a/src/backend/taler-merchant-httpd_tip-pickup.c b/src/backend/taler-merchant-httpd_tip-pickup.c
index 7b3403d2..3c810cb0 100644
--- a/src/backend/taler-merchant-httpd_tip-pickup.c
+++ b/src/backend/taler-merchant-httpd_tip-pickup.c
@@ -181,7 +181,7 @@ pickup_cleanup (struct TM_HandlerContext *hc)
  */
 static int
 run_pickup (struct MHD_Connection *connection,
-	    struct PickupContext *pc)
+            struct PickupContext *pc)
 {
   struct TALER_ReservePrivateKeyP reserve_priv;
   struct TALER_ReservePublicKeyP reserve_pub;
@@ -195,11 +195,11 @@ run_pickup (struct MHD_Connection *connection,
 				  pc->ec,
 				  pc->error_hint);
   }
-  ec = db->pickup_tip (db->cls,
-		       &pc->total,
-		       &pc->tip_id,
-		       &pc->pickup_id,
-		       &reserve_priv);
+  ec = db->pickup_tip_TR (db->cls,
+                          &pc->total,
+                          &pc->tip_id,
+                          &pc->pickup_id,
+                          &reserve_priv);
   if (TALER_EC_NONE != ec)
   {
     unsigned int response_code;
diff --git a/src/backend/taler-merchant-httpd_tip-query.c b/src/backend/taler-merchant-httpd_tip-query.c
index e4ade936..9664eaa5 100644
--- a/src/backend/taler-merchant-httpd_tip-query.c
+++ b/src/backend/taler-merchant-httpd_tip-query.c
@@ -199,7 +199,7 @@ handle_status (void *cls,
   {
     GNUNET_break_op (0);
     resume_with_response (tqc,
-			  MHD_HTTP_SERVICE_UNAVAILABLE,
+                          MHD_HTTP_SERVICE_UNAVAILABLE,
                           TMH_RESPONSE_make_error (TALER_EC_TIP_QUERY_RESERVE_STATUS_FAILED_EXCHANGE_DOWN,
                                                    "Unable to obtain reserve status from exchange"));
     return;
@@ -209,7 +209,7 @@ handle_status (void *cls,
   {
     GNUNET_break_op (0);
     resume_with_response (tqc,
-			  MHD_HTTP_SERVICE_UNAVAILABLE,
+                          MHD_HTTP_SERVICE_UNAVAILABLE,
                           TMH_RESPONSE_make_error (TALER_EC_TIP_QUERY_RESERVE_HISTORY_FAILED_EMPTY,
                                                    "Exchange returned empty reserve history"));
     return;
@@ -219,7 +219,7 @@ handle_status (void *cls,
   {
     GNUNET_break_op (0);
     resume_with_response (tqc,
-			  MHD_HTTP_SERVICE_UNAVAILABLE,
+                          MHD_HTTP_SERVICE_UNAVAILABLE,
                           TMH_RESPONSE_make_error (TALER_EC_TIP_QUERY_RESERVE_HISTORY_INVALID_NO_DEPOSIT,
                                                    "Exchange returned invalid reserve history"));
     return;
@@ -231,18 +231,18 @@ handle_status (void *cls,
   {
     GNUNET_break_op (0);
     resume_with_response (tqc,
-			  MHD_HTTP_SERVICE_UNAVAILABLE,
+                          MHD_HTTP_SERVICE_UNAVAILABLE,
                           TMH_RESPONSE_make_error (TALER_EC_TIP_QUERY_RESERVE_HISTORY_INVALID_CURRENCY,
                                                    "Exchange returned invalid reserve history"));
     return;
   }
 
   if (0 != strcasecmp (TMH_currency,
-		       history[0].amount.currency))
+                       history[0].amount.currency))
   {
     GNUNET_break_op (0);
     resume_with_response (tqc,
-			  MHD_HTTP_SERVICE_UNAVAILABLE,
+                          MHD_HTTP_SERVICE_UNAVAILABLE,
                           TMH_RESPONSE_make_error (TALER_EC_TIP_QUERY_RESERVE_CURRENCY_MISSMATCH,
                                                    "Exchange currency unexpected"));
     return;
@@ -271,11 +271,11 @@ handle_status (void *cls,
         GNUNET_CRYPTO_hash (history[i].details.in_details.wire_reference,
                             history[i].details.in_details.wire_reference_size,
                             &uuid);
-        qs = db->enable_tip_reserve (db->cls,
-                                     &tqc->reserve_priv,
-                                     &uuid,
-                                     &history[i].amount,
-                                     deposit_expiration);
+        qs = db->enable_tip_reserve_TR (db->cls,
+                                        &tqc->reserve_priv,
+                                        &uuid,
+                                        &history[i].amount,
+                                        deposit_expiration);
         if (GNUNET_OK !=
             TALER_amount_add (&tqc->amount_deposited,
                               &tqc->amount_deposited,
@@ -425,10 +425,10 @@ exchange_cont (void *cls,
  */
 int
 MH_handler_tip_query (struct TMH_RequestHandler *rh,
-                          struct MHD_Connection *connection,
-                          void **connection_cls,
-                          const char *upload_data,
-                          size_t *upload_data_size)
+                      struct MHD_Connection *connection,
+                      void **connection_cls,
+                      const char *upload_data,
+                      size_t *upload_data_size)
 {
   struct TipQueryContext *tqc;
   int res;
@@ -471,7 +471,7 @@ MH_handler_tip_query (struct TMH_RequestHandler *rh,
                                                "instance");
   if (NULL == tqc->instance)
     return TMH_RESPONSE_reply_arg_missing (connection,
-					   TALER_EC_PARAMETER_MISSING,
+                                           TALER_EC_PARAMETER_MISSING,
                                            "instance");
 
   mi = TMH_lookup_instance (tqc->instance);
@@ -495,11 +495,11 @@ MH_handler_tip_query (struct TMH_RequestHandler *rh,
   }
   tqc->reserve_priv = mi->tip_reserve;
 
-  db->preflight (db->cls);
   {
     int qs;
     for (unsigned int i=0;i<MAX_RETRIES;i++)
     {
+      db->preflight (db->cls);
       qs = db->get_authorized_tip_amount (db->cls,
                                           &tqc->reserve_priv,
                                           &tqc->amount_authorized);
@@ -517,12 +517,11 @@ MH_handler_tip_query (struct TMH_RequestHandler *rh,
     if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
     {
       /* we'll set amount_authorized to zero later once
-	 we know the currency */
+         we know the currency */
       tqc->none_authorized = GNUNET_YES;
     }
   }
 
-
   MHD_suspend_connection (connection);
   tqc->suspended = GNUNET_YES;
 
diff --git a/src/backenddb/plugin_merchantdb_postgres.c b/src/backenddb/plugin_merchantdb_postgres.c
index beeeb4eb..3aa471fb 100644
--- a/src/backenddb/plugin_merchantdb_postgres.c
+++ b/src/backenddb/plugin_merchantdb_postgres.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  (C) 2014-2018 INRIA
+  (C) 2014--2019 Taler Systems SA
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Lesser General Public License as published by the Free Software
@@ -421,20 +421,19 @@ postgres_initialize (void *cls)
                             3),
     GNUNET_PQ_make_prepare ("find_refunds_from_contract_terms_hash",
                             "SELECT"
-			    " coin_pub"
-			    ",rtransaction_id"
-			    ",refund_amount_val"
-			    ",refund_amount_frac"
-			    ",refund_amount_curr"
-			    ",refund_fee_val"
-			    ",refund_fee_frac"
-			    ",refund_fee_curr"
-			    ",reason"
-			    " FROM merchant_refunds"
+                            " coin_pub"
+                            ",rtransaction_id"
+                            ",refund_amount_val"
+                            ",refund_amount_frac"
+                            ",refund_amount_curr"
+                            ",refund_fee_val"
+                            ",refund_fee_frac"
+                            ",refund_fee_curr"
+                            ",reason"
+                            " FROM merchant_refunds"
                             " WHERE merchant_pub=$1"
                             " AND h_contract_terms=$2",
                             2),
-
     GNUNET_PQ_make_prepare ("find_contract_terms_by_date_and_range_asc",
                             "SELECT"
                             " contract_terms"
@@ -449,7 +448,6 @@ postgres_initialize (void *cls)
                             " ORDER BY row_id ASC, timestamp ASC"
                             " LIMIT $4",
                             4),
-
     GNUNET_PQ_make_prepare ("find_contract_terms_by_date_and_range",
                             "SELECT"
                             " contract_terms"
@@ -464,7 +462,6 @@ postgres_initialize (void *cls)
                             " ORDER BY row_id DESC, timestamp DESC"
                             " LIMIT $4",
                             4),
-
     GNUNET_PQ_make_prepare ("find_contract_terms_by_date_and_range_past_asc",
                             "SELECT"
                             " contract_terms"
@@ -496,7 +493,7 @@ postgres_initialize (void *cls)
     GNUNET_PQ_make_prepare ("find_deposits",
                             "SELECT"
                             " coin_pub"
-			    ",exchange_url"
+                            ",exchange_url"
                             ",amount_with_fee_val"
                             ",amount_with_fee_frac"
                             ",amount_with_fee_curr"
@@ -528,7 +525,7 @@ postgres_initialize (void *cls)
                             ",wire_fee_val"
                             ",wire_fee_frac"
                             ",wire_fee_curr"
-			    ",exchange_url"
+                            ",exchange_url"
                             ",exchange_proof"
                             " FROM merchant_deposits"
                             " WHERE h_contract_terms=$1"
@@ -618,7 +615,7 @@ postgres_initialize (void *cls)
                             "INSERT INTO merchant_tips"
                             "(reserve_priv"
                             ",tip_id"
-			    ",exchange_url"
+                            ",exchange_url"
                             ",justification"
                             ",timestamp"
                             ",amount_val"
@@ -701,7 +698,6 @@ postgres_initialize (void *cls)
     GNUNET_break (0);
     return GNUNET_SYSERR;
   }
-
   if (GNUNET_OK !=
       GNUNET_PQ_prepare_statements (pg->conn,
                                     ps))
@@ -733,6 +729,42 @@ check_connection (struct PostgresClosure *pg)
 
 
 /**
+ * Do a pre-flight check that we are not in an uncommitted transaction.
+ * If we are, try to commit the previous transaction and output a warning.
+ * Does not return anything, as we will continue regardless of the outcome.
+ *
+ * @param cls the `struct PostgresClosure` with the plugin-specific state
+ */
+static void
+postgres_preflight (void *cls)
+{
+  struct PostgresClosure *pg = cls;
+  PGresult *result;
+  ExecStatusType status;
+
+  if (NULL == pg->transaction_name)
+    return; /* all good */
+  result = PQexec (pg->conn,
+                   "COMMIT");
+  status = PQresultStatus (result);
+  if (PGRES_COMMAND_OK == status)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "BUG: Preflight check committed transaction `%s'!\n",
+                pg->transaction_name);
+  }
+  else
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "BUG: Preflight check failed to commit transaction `%s'!\n",
+                pg->transaction_name);
+  }
+  pg->transaction_name = NULL;
+  PQclear (result);
+}
+
+
+/**
  * Start a transaction.
  *
  * @param cls the `struct PostgresClosure` with the plugin-specific state
@@ -749,6 +781,7 @@ postgres_start (void *cls,
   ExecStatusType ex;
 
   check_connection (pg);
+  postgres_preflight (pg);
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Starting merchant DB transaction\n");
   result = PQexec (pg->conn,
@@ -793,42 +826,6 @@ postgres_rollback (void *cls)
 
 
 /**
- * Do a pre-flight check that we are not in an uncommitted transaction.
- * If we are, try to commit the previous transaction and output a warning.
- * Does not return anything, as we will continue regardless of the outcome.
- *
- * @param cls the `struct PostgresClosure` with the plugin-specific state
- */
-static void
-postgres_preflight (void *cls)
-{
-  struct PostgresClosure *pg = cls;
-  PGresult *result;
-  ExecStatusType status;
-
-  if (NULL == pg->transaction_name)
-    return; /* all good */
-  result = PQexec (pg->conn,
-                   "COMMIT");
-  status = PQresultStatus (result);
-  if (PGRES_COMMAND_OK == status)
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                "BUG: Preflight check committed transaction `%s'!\n",
-                pg->transaction_name);
-  }
-  else
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                "BUG: Preflight check failed to commit transaction `%s'!\n",
-                pg->transaction_name);
-  }
-  pg->transaction_name = NULL;
-  PQclear (result);
-}
-
-
-/**
  * Commit the current transaction of a database connection.
  *
  * @param cls the `struct PostgresClosure` with the plugin-specific state
@@ -846,8 +843,8 @@ postgres_commit (void *cls)
               "Committing merchant DB transaction\n");
   pg->transaction_name = NULL;
   return GNUNET_PQ_eval_prepared_non_select (pg->conn,
-					     "end_transaction",
-					     params);
+                                             "end_transaction",
+                                             params);
 }
 
 
@@ -913,6 +910,8 @@ postgres_find_paid_contract_terms_from_hash (void *cls,
     GNUNET_PQ_result_spec_end
   };
 
+  /* no preflight check here, runs in its own transaction from
+     caller (in /pay case) */
   check_connection (pg);
   return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
 						   "find_paid_contract_terms_from_hash",
@@ -1727,7 +1726,7 @@ find_payments_cb (void *cls,
 static enum GNUNET_DB_QueryStatus
 postgres_find_payments (void *cls,
                         const struct GNUNET_HashCode *h_contract_terms,
-		        const struct TALER_MerchantPublicKeyP *merchant_pub,
+                        const struct TALER_MerchantPublicKeyP *merchant_pub,
                         TALER_MERCHANTDB_CoinDepositCallback cb,
                         void *cb_cls)
 {
@@ -1744,6 +1743,8 @@ postgres_find_payments (void *cls,
   };
   enum GNUNET_DB_QueryStatus qs;
 
+  /* no preflight check here, run in its own transaction by the
+     caller! */
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Finding payment for h_contract_terms '%s'\n",
               GNUNET_h2s (h_contract_terms));
@@ -2263,6 +2264,7 @@ postgres_get_refunds_from_contract_terms_hash (void *cls,
   };
   enum GNUNET_DB_QueryStatus qs;
 
+  /* no preflight check here, run in transaction by caller! */
   TALER_LOG_DEBUG ("Looking for refund %s + %s\n",
                    GNUNET_h2s (h_contract_terms),
                    TALER_B2S (merchant_pub));
@@ -2358,6 +2360,7 @@ postgres_store_wire_fee_by_exchange (void *cls,
     GNUNET_PQ_query_param_end
   };
 
+  /* no preflight check here, run in its own transaction by the caller */
   check_connection (pg);
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
 	      "Storing wire fee for %s starting at %s of %s\n",
@@ -2540,8 +2543,8 @@ struct InsertRefundContext
  */
 static void
 process_deposits_for_refund_cb (void *cls,
-				PGresult *result,
-				unsigned int num_results)
+                                PGresult *result,
+                                unsigned int num_results)
 {
   struct InsertRefundContext *ctx = cls;
   struct TALER_Amount current_refund;
@@ -2556,7 +2559,6 @@ process_deposits_for_refund_cb (void *cls,
 
   /* Pass 1:  Collect amount of existing refunds into current_refund.
    * Also store existing refunded amount for each deposit in deposit_refund. */
-
   for (unsigned int i=0; i<num_results; i++)
   {
     struct TALER_CoinSpendPublicKeyP coin_pub;
@@ -2616,8 +2618,8 @@ process_deposits_for_refund_cb (void *cls,
     deposit_refund_fee[i] = refund_fee;
     if (GNUNET_SYSERR ==
 	TALER_amount_add (&current_refund,
-			  &current_refund,
-			  &ictx.refunded_amount))
+                      &current_refund,
+                      &ictx.refunded_amount))
     {
       GNUNET_break (0);
       ctx->qs = GNUNET_DB_STATUS_HARD_ERROR;
@@ -2642,7 +2644,6 @@ process_deposits_for_refund_cb (void *cls,
   }
 
   /* Phase 2:  Try to increase current refund until it matches desired refund */
-
   for (unsigned int i=0;i<num_results; i++)
   {
     const struct TALER_Amount *increment;
@@ -2651,9 +2652,9 @@ process_deposits_for_refund_cb (void *cls,
 
     /* How much of the coin is left after the existing refunds? */
     if (GNUNET_SYSERR ==
-	TALER_amount_subtract (&left,
-			       &deposit_amount_with_fee[i],
-			       &deposit_refund[i]))
+        TALER_amount_subtract (&left,
+                               &deposit_amount_with_fee[i],
+                               &deposit_refund[i]))
     {
       GNUNET_break (0);
       ctx->qs = GNUNET_DB_STATUS_HARD_ERROR;
@@ -2661,20 +2662,20 @@ process_deposits_for_refund_cb (void *cls,
     }
 
     if ( (0 == left.value) &&
-	 (0 == left.fraction) )
+         (0 == left.fraction) )
     {
       /* coin was fully refunded, move to next coin */
       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-		  "Coin %s fully refunded, moving to next coin\n",
-		  TALER_B2S (&deposit_coin_pubs[i]));
+                  "Coin %s fully refunded, moving to next coin\n",
+                  TALER_B2S (&deposit_coin_pubs[i]));
       continue;
     }
 
     /* How much of the refund is left? */
     if (GNUNET_SYSERR ==
-	TALER_amount_subtract (&remaining_refund,
-			       ctx->refund,
-			       &current_refund))
+        TALER_amount_subtract (&remaining_refund,
+                               ctx->refund,
+                               &current_refund))
     {
       GNUNET_break (0);
       ctx->qs = GNUNET_DB_STATUS_HARD_ERROR;
@@ -2683,7 +2684,7 @@ process_deposits_for_refund_cb (void *cls,
 
     /* By how much will we increase the refund for this coin? */
     if (0 >= TALER_amount_cmp (&remaining_refund,
-			       &left))
+                               &left))
     {
       /* remaining_refund <= left */
       increment = &remaining_refund;
@@ -2694,9 +2695,9 @@ process_deposits_for_refund_cb (void *cls,
     }
 
     if (GNUNET_SYSERR ==
-	TALER_amount_add (&current_refund,
-			  &current_refund,
-			  increment))
+        TALER_amount_add (&current_refund,
+                          &current_refund,
+                          increment))
     {
       GNUNET_break (0);
       ctx->qs = GNUNET_DB_STATUS_HARD_ERROR;
@@ -2705,28 +2706,28 @@ process_deposits_for_refund_cb (void *cls,
 
     /* actually run the refund */
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-		"Coin %s deposit amount is %s\n",
-		TALER_B2S (&deposit_coin_pubs[i]),
-		TALER_amount2s (&deposit_amount_with_fee[i]));
+                "Coin %s deposit amount is %s\n",
+                TALER_B2S (&deposit_coin_pubs[i]),
+                TALER_amount2s (&deposit_amount_with_fee[i]));
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-		"Coin %s refund will be incremented by %s\n",
-		TALER_B2S (&deposit_coin_pubs[i]),
-		TALER_amount2s (increment));
+                "Coin %s refund will be incremented by %s\n",
+                TALER_B2S (&deposit_coin_pubs[i]),
+                TALER_amount2s (increment));
     {
       enum GNUNET_DB_QueryStatus qs;
 
       if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-	  (qs = insert_refund (ctx->pg,
-			       ctx->merchant_pub,
-			       ctx->h_contract_terms,
-			       &deposit_coin_pubs[i],
-			       ctx->reason,
-			       increment,
-			       &deposit_refund_fee[i])))
+          (qs = insert_refund (ctx->pg,
+                               ctx->merchant_pub,
+                               ctx->h_contract_terms,
+                               &deposit_coin_pubs[i],
+                               ctx->reason,
+                               increment,
+                               &deposit_refund_fee[i])))
       {
-	GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-	ctx->qs = qs;
-	return;
+        GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
+        ctx->qs = qs;
+        return;
       }
     }
     /* stop immediately if we are done */
@@ -2742,8 +2743,8 @@ process_deposits_for_refund_cb (void *cls,
    * rely upon the frontend being correct.
    */
   GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-	      "The refund of %s is bigger than the order's value\n",
-	      TALER_amount2s (ctx->refund));
+              "The refund of %s is bigger than the order's value\n",
+              TALER_amount2s (ctx->refund));
   ctx->qs = GNUNET_DB_STATUS_HARD_ERROR;
 }
 
@@ -2784,13 +2785,6 @@ postgres_increase_refund_for_contract (void *cls,
               "Asked to refund %s on contract %s\n",
               TALER_amount2s (refund),
               GNUNET_h2s (h_contract_terms));
-  if (GNUNET_OK !=
-      postgres_start (cls,
-                      "increase refund"))
-  {
-    GNUNET_break (0);
-    return GNUNET_DB_STATUS_HARD_ERROR;
-  }
   ctx.pg = pg;
   ctx.qs = GNUNET_DB_STATUS_SUCCESS_ONE_RESULT;
   ctx.refund = refund;
@@ -2798,10 +2792,10 @@ postgres_increase_refund_for_contract (void *cls,
   ctx.h_contract_terms = h_contract_terms;
   ctx.merchant_pub = merchant_pub;
   qs = GNUNET_PQ_eval_prepared_multi_select (pg->conn,
-					     "find_deposits",
-					     params,
-					     &process_deposits_for_refund_cb,
-					     &ctx);
+                                             "find_deposits",
+                                             params,
+                                             &process_deposits_for_refund_cb,
+                                             &ctx);
   switch (qs)
   {
   case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
@@ -2809,28 +2803,12 @@ postgres_increase_refund_for_contract (void *cls,
                 "Unknown contract: %s (merchant_pub: %s), no refund possible\n",
                 GNUNET_h2s (h_contract_terms),
                 TALER_B2S (merchant_pub));
-    postgres_rollback (cls);
     return qs;
   case GNUNET_DB_STATUS_SOFT_ERROR:
   case GNUNET_DB_STATUS_HARD_ERROR:
-    postgres_rollback (cls);
     return qs;
   default:
     /* Got one or more deposits */
-    if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != ctx.qs)
-    {
-      postgres_rollback (cls);
-      return ctx.qs;
-    }
-    qs = postgres_commit (cls);
-    if (0 > qs)
-    {
-      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                  "Failed to commit transaction increasing refund\n");
-      return qs;
-    }
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-		"Committed refund transaction\n");
     return ctx.qs;
   }
 }
@@ -2899,11 +2877,11 @@ postgres_find_proof_by_wtid (void *cls,
  *      #GNUNET_DB_STATUS_SUCCESS_NO_RESULTS if @a credit_uuid already known
  */
 static enum GNUNET_DB_QueryStatus
-postgres_enable_tip_reserve (void *cls,
-                             const struct TALER_ReservePrivateKeyP *reserve_priv,
-                             const struct GNUNET_HashCode *credit_uuid,
-                             const struct TALER_Amount *credit,
-                             struct GNUNET_TIME_Absolute expiration)
+postgres_enable_tip_reserve_TR (void *cls,
+                                const struct TALER_ReservePrivateKeyP *reserve_priv,
+                                const struct GNUNET_HashCode *credit_uuid,
+                                const struct TALER_Amount *credit,
+                                struct GNUNET_TIME_Absolute expiration)
 {
   struct PostgresClosure *pg = cls;
   struct GNUNET_TIME_Absolute old_expiration;
@@ -3092,13 +3070,13 @@ postgres_enable_tip_reserve (void *cls,
  *      #TALER_EC_NONE upon success
  */
 static enum TALER_ErrorCode
-postgres_authorize_tip (void *cls,
-                        const char *justification,
-                        const struct TALER_Amount *amount,
-                        const struct TALER_ReservePrivateKeyP *reserve_priv,
-			const char *exchange_url,
-                        struct GNUNET_TIME_Absolute *expiration,
-                        struct GNUNET_HashCode *tip_id)
+postgres_authorize_tip_TR (void *cls,
+                           const char *justification,
+                           const struct TALER_Amount *amount,
+                           const struct TALER_ReservePrivateKeyP *reserve_priv,
+                           const char *exchange_url,
+                           struct GNUNET_TIME_Absolute *expiration,
+                           struct GNUNET_HashCode *tip_id)
 {
   struct PostgresClosure *pg = cls;
   struct GNUNET_PQ_QueryParam params[] = {
@@ -3295,11 +3273,11 @@ postgres_lookup_tip_by_id (void *cls,
  *      #TALER_EC_NONE upon success (@a reserve_priv was set)
  */
 static enum TALER_ErrorCode
-postgres_pickup_tip (void *cls,
-                     const struct TALER_Amount *amount,
-                     const struct GNUNET_HashCode *tip_id,
-                     const struct GNUNET_HashCode *pickup_id,
-                     struct TALER_ReservePrivateKeyP *reserve_priv)
+postgres_pickup_tip_TR (void *cls,
+                        const struct TALER_Amount *amount,
+                        const struct GNUNET_HashCode *tip_id,
+                        const struct GNUNET_HashCode *pickup_id,
+                        struct TALER_ReservePrivateKeyP *reserve_priv)
 {
   struct PostgresClosure *pg = cls;
   struct TALER_Amount left_amount;
@@ -3536,10 +3514,10 @@ libtaler_plugin_merchantdb_postgres_init (void *cls)
   plugin->lookup_wire_fee = &postgres_lookup_wire_fee;
   plugin->increase_refund_for_contract = &postgres_increase_refund_for_contract;
   plugin->mark_proposal_paid = &postgres_mark_proposal_paid;
-  plugin->enable_tip_reserve = &postgres_enable_tip_reserve;
-  plugin->authorize_tip = &postgres_authorize_tip;
+  plugin->enable_tip_reserve_TR = &postgres_enable_tip_reserve_TR;
+  plugin->authorize_tip_TR = &postgres_authorize_tip_TR;
   plugin->lookup_tip_by_id = &postgres_lookup_tip_by_id;
-  plugin->pickup_tip = &postgres_pickup_tip;
+  plugin->pickup_tip_TR = &postgres_pickup_tip_TR;
   plugin->start = postgres_start;
   plugin->commit = postgres_commit;
   plugin->preflight = postgres_preflight;
diff --git a/src/backenddb/test_merchantdb.c b/src/backenddb/test_merchantdb.c
index aa3db96a..fbea98c7 100644
--- a/src/backenddb/test_merchantdb.c
+++ b/src/backenddb/test_merchantdb.c
@@ -507,13 +507,13 @@ test_tipping ()
 
   RND_BLK (&tip_reserve_priv);
   if (TALER_EC_TIP_AUTHORIZE_INSUFFICIENT_FUNDS !=
-      plugin->authorize_tip (plugin->cls,
-                             "testing tips reserve unknown",
-                             &amount,
-                             &tip_reserve_priv,
-			     "http://localhost:8081/",
-                             &tip_expiration,
-                             &tip_id))
+      plugin->authorize_tip_TR (plugin->cls,
+                                "testing tips reserve unknown",
+                                &amount,
+                                &tip_reserve_priv,
+                                "http://localhost:8081/",
+                                &tip_expiration,
+                                &tip_id))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -527,22 +527,22 @@ test_tipping ()
   reserve_expiration = GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS,
                                                                                         2));
   if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-      plugin->enable_tip_reserve (plugin->cls,
-                                  &tip_reserve_priv,
-                                  &tip_credit_uuid,
-                                  &total,
-                                  reserve_expiration))
+      plugin->enable_tip_reserve_TR (plugin->cls,
+                                     &tip_reserve_priv,
+                                     &tip_credit_uuid,
+                                     &total,
+                                     reserve_expiration))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
   }
   /* check idempotency */
   if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS !=
-      plugin->enable_tip_reserve (plugin->cls,
-                                  &tip_reserve_priv,
-                                  &tip_credit_uuid,
-                                  &total,
-                                  reserve_expiration))
+      plugin->enable_tip_reserve_TR (plugin->cls,
+                                     &tip_reserve_priv,
+                                     &tip_credit_uuid,
+                                     &total,
+                                     reserve_expiration))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -550,13 +550,13 @@ test_tipping ()
   /* Make sure it has expired, so at this point the value is back at ZERO! */
   sleep (3);
   if (TALER_EC_TIP_AUTHORIZE_RESERVE_EXPIRED !=
-      plugin->authorize_tip (plugin->cls,
-                             "testing tips too late",
-                             &amount,
-                             &tip_reserve_priv,
-			     "http://localhost:8081/",
-                             &tip_expiration,
-                             &tip_id))
+      plugin->authorize_tip_TR (plugin->cls,
+                                "testing tips too late",
+                                &amount,
+                                &tip_reserve_priv,
+                                "http://localhost:8081/",
+                                &tip_expiration,
+                                &tip_id))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -567,11 +567,11 @@ test_tipping ()
   reserve_expiration = GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS,
                                                                                         2));
   if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-      plugin->enable_tip_reserve (plugin->cls,
-                                  &tip_reserve_priv,
-                                  &tip_credit_uuid,
-                                  &total,
-                                  reserve_expiration))
+      plugin->enable_tip_reserve_TR (plugin->cls,
+                                     &tip_reserve_priv,
+                                     &tip_credit_uuid,
+                                     &total,
+                                     reserve_expiration))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -581,11 +581,11 @@ test_tipping ()
   RND_BLK (&tip_credit_uuid);
   reserve_expiration = GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_DAYS);
   if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-      plugin->enable_tip_reserve (plugin->cls,
-                                  &tip_reserve_priv,
-                                  &tip_credit_uuid,
-                                  &total,
-                                  reserve_expiration))
+      plugin->enable_tip_reserve_TR (plugin->cls,
+                                     &tip_reserve_priv,
+                                     &tip_credit_uuid,
+                                     &total,
+                                     reserve_expiration))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -596,13 +596,13 @@ test_tipping ()
                  TALER_string_to_amount (CURRENCY ":4",
                                          &amount));
   if (TALER_EC_NONE !=
-      plugin->authorize_tip (plugin->cls,
-                             "testing tips",
-                             &amount,
-                             &tip_reserve_priv,
-			     "http://localhost:8081/",
-                             &tip_expiration,
-                             &tip_id))
+      plugin->authorize_tip_TR (plugin->cls,
+                                "testing tips",
+                                &amount,
+                                &tip_reserve_priv,
+                                "http://localhost:8081/",
+                                &tip_expiration,
+                                &tip_id))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -630,13 +630,13 @@ test_tipping ()
   }
   GNUNET_free (url);
   if (TALER_EC_NONE !=
-      plugin->authorize_tip (plugin->cls,
-                             "testing tips more",
-                             &amount,
-                             &tip_reserve_priv,
-			     "http://localhost:8081/",
-                             &tip_expiration,
-                             &tip_id))
+      plugin->authorize_tip_TR (plugin->cls,
+                                "testing tips more",
+                                &amount,
+                                &tip_reserve_priv,
+                                "http://localhost:8081/",
+                                &tip_expiration,
+                                &tip_id))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -653,11 +653,11 @@ test_tipping ()
                                          &inc));
   RND_BLK (&pickup_id);
   if (TALER_EC_NONE !=
-      plugin->pickup_tip (plugin->cls,
-                          &inc,
-                          &tip_id,
-                          &pickup_id,
-                          &pres))
+      plugin->pickup_tip_TR (plugin->cls,
+                             &inc,
+                             &tip_id,
+                             &pickup_id,
+                             &pres))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -671,11 +671,11 @@ test_tipping ()
   }
   RND_BLK (&pickup_id);
   if (TALER_EC_NONE !=
-      plugin->pickup_tip (plugin->cls,
-                          &inc,
-                          &tip_id,
-                          &pickup_id,
-                          &pres))
+      plugin->pickup_tip_TR (plugin->cls,
+                             &inc,
+                             &tip_id,
+                             &pickup_id,
+                             &pres))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -691,11 +691,11 @@ test_tipping ()
   /* Third attempt should fail, as we've picked up 4/4 in amount */
   RND_BLK (&pickup_id);
   if (TALER_EC_TIP_PICKUP_NO_FUNDS !=
-      plugin->pickup_tip (plugin->cls,
-                          &inc,
-                          &tip_id,
-                          &pickup_id,
-                          &pres))
+      plugin->pickup_tip_TR (plugin->cls,
+                             &inc,
+                             &tip_id,
+                             &pickup_id,
+                             &pres))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -703,13 +703,13 @@ test_tipping ()
 
   /* We authorized 8 out of 10, so going for another 4 should fail with insufficient funds */
   if (TALER_EC_TIP_AUTHORIZE_INSUFFICIENT_FUNDS !=
-      plugin->authorize_tip (plugin->cls,
-                             "testing tips insufficient funds",
-                             &amount,
-                             &tip_reserve_priv,
-			     "http://localhost:8081/",
-                             &tip_expiration,
-                             &tip_id))
+      plugin->authorize_tip_TR (plugin->cls,
+                                "testing tips insufficient funds",
+                                &amount,
+                                &tip_reserve_priv,
+                                "http://localhost:8081/",
+                                &tip_expiration,
+                                &tip_id))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
@@ -719,11 +719,11 @@ test_tipping ()
   RND_BLK (&tip_id);
   RND_BLK (&pickup_id);
   if (TALER_EC_TIP_PICKUP_TIP_ID_UNKNOWN !=
-      plugin->pickup_tip (plugin->cls,
-                          &inc,
-                          &tip_id,
-                          &pickup_id,
-                          &pres))
+      plugin->pickup_tip_TR (plugin->cls,
+                             &inc,
+                             &tip_id,
+                             &pickup_id,
+                             &pres))
   {
     GNUNET_break (0);
     return GNUNET_SYSERR;
diff --git a/src/include/taler_merchantdb_plugin.h b/src/include/taler_merchantdb_plugin.h
index f8a95019..228523b6 100644
--- a/src/include/taler_merchantdb_plugin.h
+++ b/src/include/taler_merchantdb_plugin.h
@@ -650,11 +650,11 @@ struct TALER_MERCHANTDB_Plugin
    *      #GNUNET_DB_STATUS_SUCCESS_NO_RESULTS if @a credit_uuid already known
    */
   enum GNUNET_DB_QueryStatus
-  (*enable_tip_reserve)(void *cls,
-                        const struct TALER_ReservePrivateKeyP *reserve_priv,
-                        const struct GNUNET_HashCode *credit_uuid,
-                        const struct TALER_Amount *credit,
-                        struct GNUNET_TIME_Absolute expiration);
+  (*enable_tip_reserve_TR)(void *cls,
+                           const struct TALER_ReservePrivateKeyP *reserve_priv,
+                           const struct GNUNET_HashCode *credit_uuid,
+                           const struct TALER_Amount *credit,
+                           struct GNUNET_TIME_Absolute expiration);
 
 
   /**
@@ -678,13 +678,13 @@ struct TALER_MERCHANTDB_Plugin
    *      #TALER_EC_NONE upon success
    */
   enum TALER_ErrorCode
-  (*authorize_tip)(void *cls,
-                   const char *justification,
-                   const struct TALER_Amount *amount,
-                   const struct TALER_ReservePrivateKeyP *reserve_priv,
-		   const char *exchange_url,
-                   struct GNUNET_TIME_Absolute *expiration,
-                   struct GNUNET_HashCode *tip_id);
+  (*authorize_tip_TR)(void *cls,
+                      const char *justification,
+                      const struct TALER_Amount *amount,
+                      const struct TALER_ReservePrivateKeyP *reserve_priv,
+                      const char *exchange_url,
+                      struct GNUNET_TIME_Absolute *expiration,
+                      struct GNUNET_HashCode *tip_id);
 
   /**
    * Get the total amount of authorized tips for a tipping reserve.
@@ -739,11 +739,11 @@ struct TALER_MERCHANTDB_Plugin
    *      #TALER_EC_NONE upon success (@a reserve_priv was set)
    */
   enum TALER_ErrorCode
-  (*pickup_tip)(void *cls,
-                const struct TALER_Amount *amount,
-                const struct GNUNET_HashCode *tip_id,
-                const struct GNUNET_HashCode *pickup_id,
-                struct TALER_ReservePrivateKeyP *reserve_priv);
+  (*pickup_tip_TR)(void *cls,
+                   const struct TALER_Amount *amount,
+                   const struct GNUNET_HashCode *tip_id,
+                   const struct GNUNET_HashCode *pickup_id,
+                   struct TALER_ReservePrivateKeyP *reserve_priv);
 
 
   /**
diff --git a/src/lib/test_merchant_api_new.c b/src/lib/test_merchant_api_new.c
index ca7859e4..94aafac6 100644
--- a/src/lib/test_merchant_api_new.c
+++ b/src/lib/test_merchant_api_new.c
@@ -441,7 +441,6 @@ run (void *cls,
   };
 
   struct TALER_TESTING_Command refund[] = {
-
     TALER_TESTING_cmd_refund_increase
       ("refund-increase-1",
        merchant_url,
@@ -458,7 +457,6 @@ run (void *cls,
                                      "deposit-simple",
                                      "1",
                                      MHD_HTTP_OK),
-
     /* Trying to pick up refund from non existent proposal.  */
     TALER_TESTING_cmd_refund_lookup ("refund-lookup-non-existent",
                                      merchant_url,