open_nat.c

Go to the documentation of this file.

/*!
   \file lib/vector/Vlib/open_nat.c
 
   \brief Vector library - open vector map (native format) - level 1
 
   Higher level functions for reading/writing/manipulating vectors.
 
   SPDX-FileCopyrightText: 2001-2009 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.
 */
 
#include <inttypes.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
 
#include <grass/vector.h>
#include <grass/glocale.h>
 
#include "local_proto.h"
 
static int check_coor(struct Map_info *Map);
 
/*!
   \brief Open existing vector map (level 1)
 
   Map->name and Map->mapset must be set before.
 
   \param Map pointer to Map_info structure
   \param update non-zero for write mode, otherwise read-only
 
   \return 0 success
   \return -1 error
 */
int V1_open_old_nat(struct Map_info *Map, int update)
{
    char path[GPATH_MAX];
    struct Coor_info CInfo;
 
    G_debug(1, "V1_open_old_nat(): name = %s mapset = %s", Map->name,
            Map->mapset);
 
    Vect__get_path(path, Map);
    dig_file_init(&(Map->dig_fp));
    if (update)
        Map->dig_fp.file = G_fopen_modify(path, GV_COOR_ELEMENT);
    else
        Map->dig_fp.file = G_fopen_old(path, GV_COOR_ELEMENT, Map->mapset);
 
    if (Map->dig_fp.file == NULL) {
        const char *map_name = Vect_get_full_name(Map);
        G_warning(_("Unable to open coor file for vector map <%s>"), map_name);
        G_free((void *)map_name);
        return -1;
    }
 
    /* needed to determine file size, Map->head.size will be updated
       by dig__read_head(Map) */
    Vect_coor_info(Map, &CInfo);
    Map->head.size = CInfo.size;
 
    if (!(dig__read_head(Map))) {
        G_debug(1, "dig__read_head(): failed");
        return -1;
    }
 
    /* compare coor size stored in head with real size */
    /* check should catch if LFS is required but not available */
    check_coor(Map);
 
    /* set conversion matrices */
    dig_init_portable(&(Map->head.port), Map->head.port.byte_order);
 
    /* load to memory */
    if (!update)
        dig_file_load(
            &(Map->dig_fp)); /* has currently no effect, file never loaded */
 
    return 0;
}
 
/*!
   \brief Create new vector map (level 1)
 
   \param[out] Map pointer to Map_info structure
   \param name vector map name to be created
   \param with_z 2D or 3D (unused?)
 
   \return 0 success
   \return -1 error
 */
int V1_open_new_nat(struct Map_info *Map, const char *name, int with_z)
{
    char path[GPATH_MAX];
 
    G_debug(1, "V1_open_new_nat(): name = %s with_z = %d is_tmp = %d", name,
            with_z, Map->temporary);
 
    /* Set the 'coor' file version */
    Map->head.coor_version.major = GV_COOR_VER_MAJOR;
    Map->head.coor_version.minor = GV_COOR_VER_MINOR;
    Map->head.coor_version.back_major = GV_COOR_EARLIEST_MAJOR;
    Map->head.coor_version.back_minor = GV_COOR_EARLIEST_MINOR;
 
    Vect__get_path(path, Map);
 
    /* TODO: open better */
    dig_file_init(&(Map->dig_fp));
    Map->dig_fp.file = G_fopen_new(path, GV_COOR_ELEMENT);
    if (Map->dig_fp.file == NULL)
        return -1;
    fclose(Map->dig_fp.file);
 
    dig_file_init(&(Map->dig_fp));
    Map->dig_fp.file = G_fopen_modify(path, GV_COOR_ELEMENT);
    if (Map->dig_fp.file == NULL)
        return -1;
 
    /* if overwrite OK, any existing files have already been deleted by
     * Vect_open_new(): remove this check ? */
    /* check to see if dig_plus file exists and if so, remove it */
    Vect__get_element_path(path, Map, GV_TOPO_ELEMENT);
    if (access(path, F_OK) == 0)
        unlink(path); /* remove topo file if exists */
 
    /* set conversion matrices */
    dig_init_portable(&(Map->head.port), dig__byte_order_out());
 
    /* write coor header */
    if (!(dig__write_head(Map)))
        return -1;
 
    return 0;
}
 
/* check file size */
int check_coor(struct Map_info *Map)
{
    struct Coor_info CInfo;
    off_t dif;
 
    /* NOTE: coor file is open */
    Vect_coor_info(Map, &CInfo);
    dif = CInfo.size - Map->head.size;
    G_debug(1, "coor size in head = %lu, real coor file size= %lu",
            (unsigned long)Map->head.size, (unsigned long)CInfo.size);
 
    if (dif > 0) {
        G_warning(
            _("Coor file of vector map <%s@%s> is larger than it should be "
              "(%" PRId64 " bytes excess)"),
            Map->name, Map->mapset, dif);
    }
    else if (dif < 0) {
        G_warning(_("Coor file of vector <%s@%s> is shorter than it should be "
                    "(%" PRId64 " bytes missing)."),
                  Map->name, Map->mapset, -dif);
    }
    return 1;
}