--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main/database/src/converters.h	Wed Jan 16 06:17:06 2013 +0000
@@ -0,0 +1,115 @@
+/*
+
+Copyright (C) 2012, 2013 Olaf Till <i7tiol@t-online.de>
+
+This program 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 of the License, or
+(at your option) any later version.
+
+This program 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 this program; If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+#ifndef __OCT_PQ_CONVERTERS__
+
+#define __OCT_PQ_CONVERTERS__
+
+#include <octave/oct.h>
+
+#include <stdint.h>
+#include <endian.h>
+
+#include <vector>
+#include <string>
+
+#include <postgresql/libpq-fe.h>
+
+#define OCT_PQ_NUM_CONVERTERS 13
+
+typedef std::vector<char> oct_pq_dynvec_t;
+
+typedef int (*oct_pq_to_octave_fp_t) (char *, octave_value &, int);
+
+typedef int (*oct_pq_from_octave_fp_t) (octave_value &, oct_pq_dynvec_t &);
+
+// some objects will be constants, some will be allocated
+typedef struct
+{
+  Oid oid; // read from server
+  Oid aoid; // array oid // read from server
+  Oid relid; // pg_attribute.attrelid, zero for non-composite types
+  bool is_composite; // false for constant objects
+  bool is_enum; // false for constant objects
+  bool is_not_constant; // false for constant objects
+  // const char *name; not all constants, use std::string
+  std::string name;
+  oct_pq_to_octave_fp_t to_octave_str;
+  oct_pq_to_octave_fp_t to_octave_bin;
+  oct_pq_from_octave_fp_t from_octave_str;
+  oct_pq_from_octave_fp_t from_octave_bin;
+}
+  oct_pq_conv_t;
+
+// a wrapper class around oct_pq_conv_t* to provide a default
+// constructor which nullifies it, for efficient use of maps, where
+// checking for the presence of a key while inserting it can rely on a
+// newly generated key mapping to a value of NULL
+class oct_pq_conv_wrapper_t
+{
+public:
+
+  oct_pq_conv_wrapper_t (void) : conv (NULL) {}
+
+  oct_pq_conv_wrapper_t (oct_pq_conv_t *c) : conv (c) {}
+
+  operator oct_pq_conv_t *&(void) { return conv; }
+
+  oct_pq_conv_t *&operator->(void) { return conv; }
+
+private:
+
+  oct_pq_conv_t *conv;
+};
+
+// helper function for debugging
+void print_conv (oct_pq_conv_t *);
+
+extern oct_pq_conv_t *conv_ptrs[OCT_PQ_NUM_CONVERTERS];
+
+// append bytes of value 'val' of type 'type' to dynamic char vector 'dv'
+#define OCT_PQ_PUT(dv, type, val)                       \
+  dv.resize (dv.size () + sizeof (type));               \
+  *((type *) &(dv.end ()[-sizeof (type)])) = val;
+
+// increase size of dynamic char vector 'dv' by size of uint32 and
+// store the new size in a variable named 'var' of octave_idx_type;
+// after further increasing 'dv', OCT_PQ_FILL_UINT32_PLACEHOLDER
+// should be used with equal arguments
+#define OCT_PQ_SET_UINT32_PLACEHOLDER(dv, var)          \
+  octave_idx_type var = dv.size () + sizeof (uint32_t); \
+  dv.resize (var);
+// to be used after OCT_PQ_SET_UINT32_PLACEHOLDER with equal
+// arguments; calculate difference between current size of dynamic
+// char vector 'dv' and a previous size stored in a variable named
+// 'var', and write this difference, converted to uint32_t in network
+// byte order, to the placeholder within 'dv' just before the position
+// stored in 'var'
+#define OCT_PQ_FILL_UINT32_PLACEHOLDER(dv, var)                         \
+  *((uint32_t *) &(dv[var - sizeof (uint32_t)])) = htobe32 (dv.size () - var);
+
+#define OCT_PQ_DECL_GET_INT32(retvar, pointer, type)    \
+  type retvar = be32toh (*((type *) pointer));          \
+  pointer += 4;
+
+#define OCT_PQ_GET_INT32(retvar, pointer, type)         \
+  retvar = be32toh (*((type *) pointer));          \
+  pointer += 4;
+
+#endif // __OCT_PQ_CONVERTERS__