[WiP] added TALER_AMOUNT type to Postgres - first in age_withdraw

- Added a type TALER_AMOUNT (val INT8, frac INT4) to Postgres.

- Added PLSQL functions/procedures
	- amount_normalize(a)
	- amount_add(a, b)
	- amount_left_minus_right(l, r, diff, ok bool)

- Added PQ-helper functions
	- TALER_PQ_query_param_amount_tuple()
	- TALER_PQ_result_spec_amount_tuple()

- In table 'age_withdraw', changed fields 'amount_with_fee_val' and '..._frac'
  into single field 'amount_with_fee' be of type TALER_AMOUNT

- Changed functions/stored procedures 'do_age_withdraw' and
  'get_age_withdraw' to use new APIs.

=> make check runs through without errors,
   age-withdraw and -reveal test passes.

1 files changed, 25 insertions, 0 deletions

diff --git a/src/include/taler_pq_lib.h b/src/include/taler_pq_lib.h
index db77c53b0..43561703b 100644
--- a/src/include/taler_pq_lib.h
+++ b/src/include/taler_pq_lib.h
@@ -51,6 +51,19 @@ TALER_PQ_query_param_amount_nbo (const struct TALER_AmountNBO *x);
 struct GNUNET_PQ_QueryParam
 TALER_PQ_query_param_amount (const struct TALER_Amount *x);
 
+/**
+ * Generate query parameter (as record tuple) for an amount, consisting
+ * of the two components "value" and "fraction" in this order. The
+ * types must be a 64-bit integer and a 32-bit integer
+ * respectively. The currency is dropped.
+ *
+ * @param db The database context for OID lookup
+ * @param amount pointer to the query parameter to pass
+ */
+struct GNUNET_PQ_QueryParam
+TALER_PQ_query_param_amount_tuple (
+  const struct GNUNET_PQ_Context *db,
+  const struct TALER_Amount *amount);
 
 /**
  * Generate query parameter for a denomination public
@@ -180,6 +193,18 @@ TALER_PQ_result_spec_amount (const char *name,
                              const char *currency,
                              struct TALER_Amount *amount);
 
+/**
+ * Currency amount expected, from a record-field of (DB) taler_amount type
+ *
+ * @param name name of the field in the table
+ * @param currency currency to use for @a amount
+ * @param[out] amount where to store the result
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_PQ_ResultSpec
+TALER_PQ_result_spec_amount_tuple (const char *name,
+                                   const char *currency,
+                                   struct TALER_Amount *amount);
 
 /**
  * Denomination public key expected.