--- /dev/null
+/*
+ This file is part of GNUnet
+ Copyright (C) 2017 GNUnet e.V.
+
+ GNUnet 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.
+
+ GNUnet 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
+ GNUnet; see the file COPYING. If not, If not, see <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file include/gnunet_sq_lib.h
+ * @brief helper functions for Sqlite3 DB interactions
+ * @author Christian Grothoff
+ */
+#ifndef GNUNET_SQ_LIB_H
+#define GNUNET_SQ_LIB_H
+
+#include <sqlite/sqlite3.h>
+#include "gnunet_util_lib.h"
+
+
+/**
+ * Function called to convert input argument into SQL parameters.
+ *
+ * @param cls closure
+ * @param data pointer to input argument
+ * @param data_len number of bytes in @a data (if applicable)
+ * @param stmt sqlite statement to bind parameters for
+ * @param off offset of the argument to bind in @a stmt, numbered from 1,
+ * so immediately suitable for passing to `sqlite3_bind`-functions.
+ * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
+ */
+typedef int
+(*GNUNET_SQ_QueryConverter)(void *cls,
+ const void *data,
+ size_t data_len,
+ sqlite3_stmt *stmt,
+ unsigned int off);
+
+
+/**
+ * @brief Description of a DB query parameter.
+ */
+struct GNUNET_SQ_QueryParam
+{
+
+ /**
+ * Function for how to handle this type of entry.
+ */
+ GNUNET_SQ_QueryConverter conv;
+
+ /**
+ * Closure for @e conv.
+ */
+ void *conv_cls;
+
+ /**
+ * Data or NULL.
+ */
+ const void *data;
+
+ /**
+ * Size of @e data
+ */
+ size_t size;
+
+ /**
+ * Number of parameters eaten by this operation.
+ */
+ unsigned int num_params;
+};
+
+
+/**
+ * End of query parameter specification.
+ */
+#define GNUNET_SQ_query_param_end { NULL, NULL, NULL, 0, 0 }
+
+
+/**
+ * Generate query parameter for a buffer @a ptr of
+ * @a ptr_size bytes.
+ *
+ * @param ptr pointer to the query parameter to pass
+ * @oaran ptr_size number of bytes in @a ptr
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_fixed_size (const void *ptr,
+ size_t ptr_size);
+
+
+
+/**
+ * Generate query parameter for a string.
+ *
+ * @param ptr pointer to the string query parameter to pass
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_string (const char *ptr);
+
+
+/**
+ * Generate fixed-size query parameter with size determined
+ * by variable type.
+ *
+ * @param x pointer to the query parameter to pass.
+ */
+#define GNUNET_SQ_query_param_auto_from_type(x) GNUNET_SQ_query_param_fixed_size ((x), sizeof (*(x)))
+
+
+/**
+ * Generate query parameter for an RSA public key. The
+ * database must contain a BLOB type in the respective position.
+ *
+ * @param x the query parameter to pass.
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_rsa_public_key (const struct GNUNET_CRYPTO_RsaPublicKey *x);
+
+
+/**
+ * Generate query parameter for an RSA signature. The
+ * database must contain a BLOB type in the respective position.
+ *
+ * @param x the query parameter to pass
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_rsa_signature (const struct GNUNET_CRYPTO_RsaSignature *x);
+
+
+/**
+ * Generate query parameter for an absolute time value.
+ * The database must store a 64-bit integer.
+ *
+ * @param x pointer to the query parameter to pass
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_absolute_time (const struct GNUNET_TIME_Absolute *x);
+
+
+/**
+ * Generate query parameter for an absolute time value.
+ * The database must store a 64-bit integer.
+ *
+ * @param x pointer to the query parameter to pass
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_absolute_time_nbo (const struct GNUNET_TIME_AbsoluteNBO *x);
+
+
+/**
+ * Generate query parameter for an uint16_t in host byte order.
+ *
+ * @param x pointer to the query parameter to pass
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_uint16 (const uint16_t *x);
+
+
+/**
+ * Generate query parameter for an uint32_t in host byte order.
+ *
+ * @param x pointer to the query parameter to pass
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_uint32 (const uint32_t *x);
+
+
+/**
+ * Generate query parameter for an uint16_t in host byte order.
+ *
+ * @param x pointer to the query parameter to pass
+ */
+struct GNUNET_SQ_QueryParam
+GNUNET_SQ_query_param_uint64 (const uint64_t *x);
+
+
+/**
+ * Extract data from a Postgres database @a result at row @a row.
+ *
+ * @param cls closure
+ * @param result where to extract data from
+ * @param int row to extract data from
+ * @param[in,out] dst_size where to store size of result, may be NULL
+ * @param[out] dst where to store the result
+ * @return
+ * #GNUNET_YES if all results could be extracted
+ * #GNUNET_SYSERR if a result was invalid (non-existing field or NULL)
+ */
+typedef int
+(*GNUNET_SQ_ResultConverter)(void *cls,
+ sqlite3_stmt *result,
+ int row,
+ size_t *dst_size,
+ void *dst);
+
+
+/**
+ * Function called to clean up memory allocated
+ * by a #GNUNET_SQ_ResultConverter.
+ *
+ * @param cls closure
+ * @param rd result data to clean up
+ */
+typedef void
+(*GNUNET_SQ_ResultCleanup)(void *cls,
+ void *rd);
+
+
+/**
+ * @brief Description of a DB result cell.
+ */
+struct GNUNET_SQ_ResultSpec
+{
+
+ /**
+ * What is the format of the result?
+ */
+ GNUNET_SQ_ResultConverter conv;
+
+ /**
+ * Function to clean up result data, NULL if cleanup is
+ * not necessary.
+ */
+ GNUNET_SQ_ResultCleanup cleaner;
+
+ /**
+ * Closure for @e conv and @e cleaner.
+ */
+ void *cls;
+
+ /**
+ * Destination for the data.
+ */
+ void *dst;
+
+ /**
+ * Allowed size for the data, 0 for variable-size
+ * (in this case, the type of @e dst is a `void **`
+ * and we need to allocate a buffer of the right size).
+ */
+ size_t dst_size;
+
+ /**
+ * Where to store actual size of the result.
+ */
+ size_t *result_size;
+
+};
+
+
+/**
+ * End of result parameter specification.
+ *
+ * @return array last entry for the result specification to use
+ */
+#define GNUNET_SQ_result_spec_end { NULL, NULL, NULL, NULL, 0, NULL }
+
+
+/**
+ * Variable-size result expected.
+ *
+ * @param[out] dst where to store the result, allocated
+ * @param[out] sptr where to store the size of @a dst
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_variable_size (void **dst,
+ size_t *sptr);
+
+
+/**
+ * Fixed-size result expected.
+ *
+ * @param[out] dst where to store the result
+ * @param dst_size number of bytes in @a dst
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_fixed_size (void *dst,
+ size_t dst_size);
+
+
+/**
+ * We expect a fixed-size result, with size determined by the type of `* dst`
+ *
+ * @param dst point to where to store the result, type fits expected result size
+ * @return array entry for the result specification to use
+ */
+#define GNUNET_SQ_result_spec_auto_from_type(dst) GNUNET_SQ_result_spec_fixed_size (name, (dst), sizeof (*(dst)))
+
+
+/**
+ * Variable-size result expected.
+ *
+ * @param[out] dst where to store the result, allocated
+ * @param[out] sptr where to store the size of @a dst
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_variable_size (void **dst,
+ size_t *sptr);
+
+
+/**
+ * 0-terminated string expected.
+ *
+ * @param[out] dst where to store the result, allocated
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_string (char **dst);
+
+
+/**
+ * RSA public key expected.
+ *
+ * @param[out] rsa where to store the result
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_rsa_public_key (struct GNUNET_CRYPTO_RsaPublicKey **rsa);
+
+
+/**
+ * RSA signature expected.
+ *
+ * @param[out] sig where to store the result;
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_rsa_signature (struct GNUNET_CRYPTO_RsaSignature **sig);
+
+
+/**
+ * Absolute time expected.
+ *
+ * @param[out] at where to store the result
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_absolute_time (struct GNUNET_TIME_Absolute *at);
+
+
+/**
+ * Absolute time expected.
+ *
+ * @param[out] at where to store the result
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_absolute_time_nbo (struct GNUNET_TIME_AbsoluteNBO *at);
+
+
+/**
+ * uint16_t expected.
+ *
+ * @param[out] u16 where to store the result
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_uint16 (uint16_t *u16);
+
+
+/**
+ * uint32_t expected.
+ *
+ * @param[out] u32 where to store the result
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_uint32 (uint32_t *u32);
+
+
+/**
+ * uint64_t expected.
+ *
+ * @param[out] u64 where to store the result
+ * @return array entry for the result specification to use
+ */
+struct GNUNET_SQ_ResultSpec
+GNUNET_SQ_result_spec_uint64 (uint64_t *u64);
+
+
+/**
+ * Execute a prepared statement.
+ *
+ * @param db_conn database connection
+ * @param params parameters to the statement
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_SQ_bind (sqlite3_stmt *stmt,
+ const struct GNUNET_SQ_QueryParam *params);
+
+
+/**
+ * Extract results from a query result according to the given specification.
+ *
+ * @param result result to process
+ * @param[in,out] rs result specification to extract for
+ * @param row row from the result to extract
+ * @return
+ * #GNUNET_YES if all results could be extracted
+ * #GNUNET_SYSERR if a result was invalid (non-existing field)
+ */
+int
+GNUNET_SQ_extract_result (sqlite3_stmt *result,
+ struct GNUNET_SQ_ResultSpec *rs,
+ int row);
+
+
+/**
+ * Free all memory that was allocated in @a rs during
+ * #GNUNET_SQ_extract_result().
+ *
+ * @param rs reult specification to clean up
+ */
+void
+GNUNET_SQ_cleanup_result (struct GNUNET_SQ_ResultSpec *rs);
+
+
+#endif /* GNUNET_SQ_LIB_H_ */
+
+/* end of include/gnunet_sq_lib.h */