1 files changed, 132 insertions, 0 deletions

diff --git a/src/include/taler_db_lib.h b/src/include/taler_db_lib.h
new file mode 100644
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+++ b/src/include/taler_db_lib.h
@@ -0,0 +1,132 @@
+/*
+  This file is part of TALER
+  (C) 2014 Christian Grothoff (and other contributing authors)
+
+  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, If not, see <http://www.gnu.org/licenses/>
+*/
+
+
+/**
+ * @file include/taler_db_lib.h
+ * @brief helper functions for DB interactions
+ * @author Sree Harsha Totakura <sreeharsha@totakura.in>
+ * @author Florian Dold
+ */
+
+#ifndef TALER_DB_LIB_H_
+#define TALER_DB_LIB_H_
+
+#include <libpq-fe.h>
+#include "taler_util.h"
+
+#define TALER_DB_QUERY_PARAM_END { NULL, 0, 0 }
+#define TALER_DB_QUERY_PARAM_PTR(x) { (x), sizeof (*(x)), 1 }
+#define TALER_DB_QUERY_PARAM_PTR_SIZED(x, s) { (x), (s), 1 }
+
+
+#define TALER_DB_RESULT_SPEC_END { NULL, 0, NULL }
+#define TALER_DB_RESULT_SPEC(name, dst) { (void *) (dst), sizeof (*(dst)), (name) }
+#define TALER_DB_RESULT_SPEC_SIZED(name, dst, s) { (void *) (dst), (s), (name) }
+
+
+/**
+ * Description of a DB query parameter.
+ */
+struct TALER_DB_QueryParam
+{
+  /**
+   * Data or NULL
+   */
+  const void *data;
+  /**
+   * Size of 'data'
+   */
+  size_t size;
+  /**
+   * Non-null if this is not the last parameter.
+   * This allows for null as sentinal value.
+   */
+  int more;
+};
+
+
+/**
+ * Description of a DB result cell.
+ */
+struct TALER_DB_ResultSpec
+{
+  /**
+   * Destination for the data.
+   */
+  void *dst;
+
+  /**
+   * Allowed size for the data.
+   */
+  size_t dst_size;
+
+  /**
+   * Field name of the desired result.
+   */
+  char *fname;
+};
+
+
+/**
+ * Execute a prepared statement.
+ */
+PGresult *
+TALER_DB_exec_prepared (PGconn *db_conn,
+                        const char *name,
+                        const struct TALER_DB_QueryParam *params);
+
+
+/**
+ * Extract results from a query result according to the given specification.
+ * If colums are NULL, the destination is not modified, and GNUNET_NO
+ * is returned.
+ *
+ * @return
+ *   GNUNET_YES if all results could be extracted
+ *   GNUNET_NO if at least one result was NULL
+ *   GNUNET_SYSERR if a result was invalid (non-existing field)
+ */
+int
+TALER_DB_extract_result (PGresult *result, struct TALER_DB_ResultSpec *rs, int row);
+
+
+int
+TALER_DB_field_isnull (PGresult *result,
+                       int row,
+                       const char *fname);
+
+
+int
+TALER_DB_extract_amount_nbo (PGresult *result,
+                             int row,
+                             const char *val_name,
+                             const char *frac_name,
+                             const char *curr_name,
+                             struct TALER_AmountNBO *r_amount_nbo);
+
+
+int
+TALER_DB_extract_amount (PGresult *result,
+                         int row,
+                         const char *val_name,
+                         const char *frac_name,
+                         const char *curr_name,
+                         struct TALER_Amount *r_amount);
+
+#endif  /* TALER_DB_LIB_H_ */
+
+/* end of include/taler_db_lib.h */