vector/Vlib/rewind.c

Go to the documentation of this file.

/*!
   \file lib/vector/Vlib/rewind.c
 
   \brief Vector library - rewind data
 
   Higher level functions for reading/writing/manipulating vectors.
 
   SPDX-FileCopyrightText: 2001-2009, 2011-2012 GRASS Development Team
   SPDX-License-Identifier: GPL-2.0-or-later
 
   \author Original author CERL, probably Dave Gerdes or Mike Higgins.
   \author Update to GRASS 5.7 Radim Blazek and David D. Gray.
   \author Level 3 by Martin Landa <landa.martin gmail.com>
 */
 
#include <grass/vector.h>
#include <grass/glocale.h>
 
static int rew_dummy(struct Map_info *Map G_UNUSED)
{
    return -1;
}
 
#if !defined HAVE_POSTGRES
static int format(struct Map_info *Map G_UNUSED)
{
    G_fatal_error(_("Requested format is not compiled in this version"));
    return 0;
}
#endif
 
static int (*Rewind_array[][4])(struct Map_info *) = {
    {rew_dummy, V1_rewind_nat, V2_rewind_nat, rew_dummy},
    {rew_dummy, V1_rewind_ogr, V2_rewind_ogr, rew_dummy},
    {rew_dummy, V1_rewind_ogr, V2_rewind_ogr, rew_dummy}
#ifdef HAVE_POSTGRES
    ,
    {rew_dummy, V1_rewind_pg, V2_rewind_pg, V2_rewind_pg}
#else
    ,
    {rew_dummy, format, format, rew_dummy}
#endif
};
 
/*!
   \brief Rewind vector map to cause reads to start at beginning
 
   \param Map pointer to Map_info structure
 
   \return 0 on success
   \return -1 on error
 */
int Vect_rewind(struct Map_info *Map)
{
    if (!VECT_OPEN(Map))
        return -1;
 
    G_debug(1, "Vect_Rewind(): name = %s level = %d", Map->name, Map->level);
 
    return (*Rewind_array[Map->format][Map->level])(Map);
}