dbt_base.c

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/*
 * $Id: dbt_base.c 5713 2009-03-16 17:29:25Z henningw $
 *
 * DBText module core functions
 *
 * Copyright (C) 2001-2003 FhG Fokus
 *
 * This file is part of Kamailio, a free SIP server.
 *
 * Kamailio 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 2 of the License, or
 * (at your option) any later version
 *
 * Kamailio 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, write to the Free Software 
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 * 
 * History:
 * --------
 * 2009-03-01 added support for ORDER-BY clause by Edgar Holleis
 * 2003-01-30 created by Daniel
 * 
 */

#include <string.h>

#include "../../str.h"
#include "../../mem/mem.h"
#include "../../mem/shm_mem.h"
 
#include "dbtext.h"
#include "dbt_res.h"
#include "dbt_api.h"

#ifndef CFG_DIR
#define CFG_DIR "/tmp"
#endif

#define DBT_ID    "text://"
#define DBT_ID_LEN   (sizeof(DBT_ID)-1)
#define DBT_PATH_LEN 256
/*
 * Initialize database connection
 */
db_con_t* dbt_init(const str* _sqlurl)
{
   db_con_t* _res;
   str _s;
   char dbt_path[DBT_PATH_LEN];
   
   if (!_sqlurl || !_sqlurl->s)
   {
      LM_ERR("invalid parameter value\n");
      return NULL;
   }
   _s.s = _sqlurl->s;
   _s.len = _sqlurl->len;
   if(_s.len <= DBT_ID_LEN || strncmp(_s.s, DBT_ID, DBT_ID_LEN)!=0)
   {
      LM_ERR("invalid database URL - should be:"
         " <%s[/]path/to/directory>\n", DBT_ID);
      return NULL;
   }
   /*
    * it would be possible to use the _sqlurl here, but the core API is
    * defined with a const str*, so this code would be not valid.
    */
   _s.s   += DBT_ID_LEN;
   _s.len -= DBT_ID_LEN;
   if(_s.s[0]!='/')
   {
      if(sizeof(CFG_DIR)+_s.len+2 > DBT_PATH_LEN)
      {
         LM_ERR("path to database is too long\n");
         return NULL;
      }
      strcpy(dbt_path, CFG_DIR);
      dbt_path[sizeof(CFG_DIR)] = '/';
      strncpy(&dbt_path[sizeof(CFG_DIR)+1], _s.s, _s.len);
      _s.len += sizeof(CFG_DIR);
      _s.s = dbt_path;
   }
   
   _res = pkg_malloc(sizeof(db_con_t)+sizeof(dbt_con_t));
   if (!_res)
   {
      LM_ERR("no pkg memory left\n");
      return NULL;
   }
   memset(_res, 0, sizeof(db_con_t) + sizeof(dbt_con_t));
   _res->tail = (unsigned long)((char*)_res+sizeof(db_con_t));

   LM_INFO("using database at: %.*s", _s.len, _s.s);
   DBT_CON_CONNECTION(_res) = dbt_cache_get_db(&_s);
   if (!DBT_CON_CONNECTION(_res))
   {
      LM_ERR("cannot get the link to database\n");
      return NULL;
   }

    return _res;
}


/*
 * Close a database connection
 */
void dbt_close(db_con_t* _h)
{
   if (!_h) 
   {
      LM_ERR("invalid parameter value\n");
      return;
   }
   
   if (DBT_CON_RESULT(_h)) 
      dbt_result_free(DBT_CON_RESULT(_h));
   
   pkg_free(_h);
    return;
}


/*
 * Free all memory allocated by get_result
 */
int dbt_free_result(db_con_t* _h, db_res_t* _r)
{
   if ((!_h) || (!_r))
   {
      LM_ERR("invalid parameter value\n");
      return -1;
   }

   if(db_free_result(_r) < 0) 
   {
      LM_ERR("unable to free result structure\n");
      return -1;
   }

   
   if(dbt_result_free(DBT_CON_RESULT(_h)) < 0) 
   {
      LM_ERR("unable to free internal structure\n");
      return -1;
   }
   DBT_CON_RESULT(_h) = NULL;
   return 0;
}


/*
 * Query table for specified rows
 * _h: structure representing database connection
 * _k: key names
 * _op: operators
 * _v: values of the keys that must match
 * _c: column names to return
 * _n: number of key=values pairs to compare
 * _nc: number of columns to return
 * _o: order by the specified column
 */

int dbt_query(db_con_t* _h, db_key_t* _k, db_op_t* _op, db_val_t* _v, 
         db_key_t* _c, int _n, int _nc, db_key_t _o, db_res_t** _r)
{
   dbt_table_p _tbc = NULL;
   dbt_row_p _drp = NULL;
   dbt_result_p _dres = NULL;
   
   int *lkey=NULL, *lres=NULL;
   
   db_key_t *_o_k=NULL;    /* columns in order-by */
   char *_o_op=NULL;       /* operators for oder-by */
   int _o_n;               /* no of elements in order-by */
   int *_o_l=NULL;         /* column selection for order-by */
   int _o_nc;              /* no of elements in _o_l but not lres */

   if ((!_h) || (!_r) || !CON_TABLE(_h))
   {
      LM_ERR("invalid parameters\n");
      return -1;
   }
   *_r = NULL;
   

   if (_o)
   {
      if (dbt_parse_orderbyclause(&_o_k, &_o_op, &_o_n, _o) < 0)
         return -1;
   }

   /* lock database */
   _tbc = dbt_db_get_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
   if(!_tbc)
   {
      LM_ERR("table %.*s does not exist!\n", CON_TABLE(_h)->len, CON_TABLE(_h)->s);
      return -1;
   }


   if(!_tbc || _tbc->nrcols < _nc)
   {
      LM_ERR("table not loaded!\n");
      goto error;
   }
   if(_k)
   {
      lkey = dbt_get_refs(_tbc, _k, _n);
      if(!lkey)
         goto error;
   }
   if(_c)
   {
      lres = dbt_get_refs(_tbc, _c, _nc);
      if(!lres)
         goto error;
   }
   if(_o_k)
   {
      _o_l = dbt_get_refs(_tbc, _o_k, _o_n);
      if (!_o_l)
         goto error;
      /* enlarge select-columns lres by all order-by columns, _o_nc is how many */
      if (dbt_mangle_columnselection(&lres, &_nc, &_o_nc, _o_l, _o_n) < 0)
         goto error;
   }

   LM_DBG("new res with %d cols\n", _nc);
   _dres = dbt_result_new(_tbc, lres, _nc);
   
   if(!_dres)
      goto error;
   
   _drp = _tbc->rows;
   while(_drp)
   {
      if(dbt_row_match(_tbc, _drp, lkey, _op, _v, _n))
      {
         if(dbt_result_extract_fields(_tbc, _drp, lres, _dres))
         {
            LM_ERR("failed to extract result fields!\n");
            goto clean;
         }
      }
      _drp = _drp->next;
   }

   dbt_table_update_flags(_tbc, DBT_TBFL_ZERO, DBT_FL_IGN, 1);
   
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));

   if (_o_l)
   {
      if (_dres->nrrows > 1)
      {
         if (dbt_sort_result(_dres, _o_l, _o_op, _o_n, lres, _nc) < 0)
            goto error_nounlock;
      }

      /* last but not least, remove surplus columns */
      if (_o_nc)
         dbt_project_result(_dres, _o_nc);
   }


   /* dbt_result_print(_dres); */
   
   DBT_CON_RESULT(_h) = _dres;
   
   if(lkey)
      pkg_free(lkey);
   if(lres)
      pkg_free(lres);
   if(_o_k)
      pkg_free(_o_k);
   if(_o_op)
      pkg_free(_o_op);
   if(_o_l)
      pkg_free(_o_l);

   return dbt_get_result(_h, _r);

error:
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
error_nounlock:
   if(lkey)
      pkg_free(lkey);
   if(lres)
      pkg_free(lres);
   if(_o_k)
      pkg_free(_o_k);
   if(_o_op)
      pkg_free(_o_op);
   if(_o_l)
      pkg_free(_o_l);
   LM_ERR("failed to query the table!\n");

   return -1;

clean:
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
   if(lkey)
      pkg_free(lkey);
   if(lres)
      pkg_free(lres);
   if(_o_k)
      pkg_free(_o_k);
   if(_o_op)
      pkg_free(_o_op);
   if(_o_l)
      pkg_free(_o_l);
   if(_dres)
      dbt_result_free(_dres);

   return -1;
}

/*
 * Raw SQL query -- is not the case to have this method
 */
int dbt_raw_query(db_con_t* _h, char* _s, db_res_t** _r)
{
   *_r = NULL;
    return -1;
}

/*
 * Insert a row into table
 */
int dbt_insert(db_con_t* _h, db_key_t* _k, db_val_t* _v, int _n)
{
   dbt_table_p _tbc = NULL;
   dbt_row_p _drp = NULL;
   
   int *lkey=NULL, i, j;
   
   if (!_h || !CON_TABLE(_h))
   {
      LM_ERR("invalid parameter\n");
      return -1;
   }
   if(!_k || !_v || _n<=0)
   {
      LM_ERR("no key-value to insert\n");
      return -1;
   }
   
   /* lock database */
   _tbc = dbt_db_get_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
   if(!_tbc)
   {
      LM_ERR("table %.*s does not exist!\n", CON_TABLE(_h)->len, CON_TABLE(_h)->s);
      return -1;
   }

   if(_tbc->nrcols<_n)
   {
      LM_ERR("more values than columns!!\n");
      goto error;
   }
   
   if(_k)
   {
      lkey = dbt_get_refs(_tbc, _k, _n);
      if(!lkey)
         goto error;
   }
   _drp = dbt_row_new(_tbc->nrcols);
   if(!_drp)
   {
      LM_ERR("no shm memory for a new row!!\n");
      goto error;
   }
   
   for(i=0; i<_n; i++)
   {
      j = (lkey)?lkey[i]:i;
      if(dbt_is_neq_type(_tbc->colv[j]->type, _v[i].type))
      {
         LM_ERR("incompatible types v[%d] - c[%d]!\n", i, j);
         goto clean;
      }
      if(_v[i].type == DB_STRING && !_v[i].nul)
         _v[i].val.str_val.len = strlen(_v[i].val.string_val);
      if(dbt_row_set_val(_drp, &(_v[i]), _tbc->colv[j]->type, j))
      {
         LM_ERR("cannot set v[%d] in c[%d]!\n", i, j);
         goto clean;
      }
      
   }

   if(dbt_table_add_row(_tbc, _drp))
   {
      LM_ERR("cannot insert the new row!!\n");
      goto clean;
   }

   /* dbt_print_table(_tbc, NULL); */
   
   /* unlock databse */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));

   if(lkey)
      pkg_free(lkey);

    return 0;
   
error:
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
   if(lkey)
      pkg_free(lkey);
   LM_ERR("failed to insert row in table!\n");
    return -1;
   
clean:
   if(lkey)
      pkg_free(lkey);
   
   if(_drp) // free row
      dbt_row_free(_tbc, _drp);
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
   
    return -1;
}

/*
 * Delete a row from table
 */
int dbt_delete(db_con_t* _h, db_key_t* _k, db_op_t* _o, db_val_t* _v, int _n)
{
   dbt_table_p _tbc = NULL;
   dbt_row_p _drp = NULL, _drp0 = NULL;
   int *lkey = NULL;

   if (!_h || !CON_TABLE(_h))
   {
      LM_ERR("invalid parameters\n");
      return -1;
   }

   /* lock database */
   _tbc = dbt_db_get_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
   if(!_tbc)
   {
      LM_ERR("failed to load table <%.*s>!\n", CON_TABLE(_h)->len,
            CON_TABLE(_h)->s);
      return -1;
   }

   if(!_k || !_v || _n<=0)
   {
      LM_DBG("deleting all records\n");
      dbt_table_free_rows(_tbc);
      /* unlock databse */
      dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
      return 0;
   }

   lkey = dbt_get_refs(_tbc, _k, _n);
   if(!lkey)
      goto error;
   
   _drp = _tbc->rows;
   while(_drp)
   {
      _drp0 = _drp->next;
      if(dbt_row_match(_tbc, _drp, lkey, _o, _v, _n))
      {
         // delete row
         if(_drp->prev)
            (_drp->prev)->next = _drp->next;
         else
            _tbc->rows = _drp->next;
         if(_drp->next)
            (_drp->next)->prev = _drp->prev;
         _tbc->nrrows--;
         // free row
         dbt_row_free(_tbc, _drp);
      }
      _drp = _drp0;
   }

   dbt_table_update_flags(_tbc, DBT_TBFL_MODI, DBT_FL_SET, 1);
   
   /* dbt_print_table(_tbc, NULL); */
   
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));

   if(lkey)
      pkg_free(lkey);
   
   return 0;
   
error:
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));

   LM_ERR("failed to delete from table!\n");
   return -1;
}

/*
 * Update a row in table
 */
int dbt_update(db_con_t* _h, db_key_t* _k, db_op_t* _o, db_val_t* _v,
         db_key_t* _uk, db_val_t* _uv, int _n, int _un)
{
   dbt_table_p _tbc = NULL;
   dbt_row_p _drp = NULL;
   int i;
   int *lkey=NULL, *lres=NULL;

   if (!_h || !CON_TABLE(_h) || !_uk || !_uv || _un <= 0)
   {
      LM_ERR("invalid parameters\n");
      return -1;
   }
   
   /* lock database */
   _tbc = dbt_db_get_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));
   if(!_tbc)
   {
      LM_ERR("table %.*s does not exist!\n", CON_TABLE(_h)->len, CON_TABLE(_h)->s);
      return -1;
   }

   if(_k)
   {
      lkey = dbt_get_refs(_tbc, _k, _n);
      if(!lkey)
         goto error;
   }
   lres = dbt_get_refs(_tbc, _uk, _un);
   if(!lres)
      goto error;
   _drp = _tbc->rows;
   while(_drp)
   {
      if(dbt_row_match(_tbc, _drp, lkey, _o, _v, _n))
      { // update fields
         for(i=0; i<_un; i++)
         {
            if(dbt_is_neq_type(_tbc->colv[lres[i]]->type, _uv[i].type))
            {
               LM_ERR("incompatible types!\n");
               goto error;
            }
            
            if(dbt_row_update_val(_drp, &(_uv[i]),
                     _tbc->colv[lres[i]]->type, lres[i]))
            {
               LM_ERR("cannot set v[%d] in c[%d]!\n",
                     i, lres[i]);
               goto error;
            }
         }
      }
      _drp = _drp->next;
   }

   dbt_table_update_flags(_tbc, DBT_TBFL_MODI, DBT_FL_SET, 1);
   
   /* dbt_print_table(_tbc, NULL); */
   
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));

   if(lkey)
      pkg_free(lkey);
   if(lres)
      pkg_free(lres);

    return 0;

error:
   /* unlock database */
   dbt_release_table(DBT_CON_CONNECTION(_h), CON_TABLE(_h));

   if(lkey)
      pkg_free(lkey);
   if(lres)
      pkg_free(lres);
   
   LM_ERR("failed to update the table!\n");

   return -1;
}