key_value4.c

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/*!
   \file lib/gis/key_value4.c
 
   \brief Key_Value management.
 
   (C) 2001-2014 by the GRASS Development Team
 
   This program is free software under the
   GNU General Public License (>=v2).
   Read the file COPYING that comes with GRASS
   for details.
 
   \author CERL
 */
 
#include <grass/gis.h>
#include <string.h>
 
/*!
   \brief Update file, set up value for given key
 
   \param[in] file  filename to be updated
   \param[in] key   key value
   \param[in] value value to be updated
 */
void G_update_key_value_file(const char *file, const char *key,
                             const char *value)
{
    struct Key_Value *kv;
 
    kv = G_read_key_value_file(file);
    G_set_key_value(key, value, kv);
    G_write_key_value_file(file, kv);
    G_free_key_value(kv);
}
 
/*!
   \brief Look up for key in file
 
   \param[in]  file  filename
   \param[in]  key   key to be found in file
   \param[out] value value for key
   \param[in]  n     number of characters to be copied
 
   \return 0 not found
   \return 1 ok
 */
int G_lookup_key_value_from_file(const char *file, const char *key,
                                 char value[], int n)
{
    struct Key_Value *kv;
    const char *v;
 
    *value = '\0';
    kv = G_read_key_value_file(file);
 
    v = G_find_key_value(key, kv);
 
    if (v) {
        strncpy(value, v, n);
        value[n - 1] = '\0';
    }
 
    G_free_key_value(kv);
 
    return v ? 1 : 0;
}