archived-lcd4linux/plugin_mysql.c

/* $Id: plugin_mysql.c,v 1.5 2005/04/01 05:16:04 reinelt Exp $
 *
 * plugin for execute SQL queries into a MySQL DBSM.
 *
 * Copyright (C) 2004 Javier Garcia <javi@gsmlandia.com>
 * Copyright (C) 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
 *
 * This file is part of LCD4Linux.
 *
 * LCD4Linux 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, or (at your option)
 * any later version.
 *
 * LCD4Linux 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * $Log: plugin_mysql.c,v $
 * Revision 1.5  2005/04/01 05:16:04  reinelt
 * moved plugin init stuff to a seperate function called on first use
 *
 * Revision 1.4  2005/01/18 06:30:23  reinelt
 * added (C) to all copyright statements
 *
 * Revision 1.3  2004/03/21 22:05:53  reinelt
 * MySQL plugin fixes from Javi
 *
 * Revision 1.2  2004/03/20 23:09:01  reinelt
 * MySQL plugin fixes from Javi
 *
 * Revision 1.1  2004/03/10 07:16:15  reinelt
 * MySQL plugin from Javier added
 *
 */

/* DOC:
 * To compile the plugin remember to add -lmysqlclient option into Makefile. I.E: CC = gcc -lmysqlclient 
 * or run:
 * $ gcc -I/usr/include/mysql -L/usr/lib/mysql plugin_mysql.c -lmysqlclient -o plugin_mysql.o
 *
 * exported functions:
 *
 * int plugin_init_mysql (void)
 *
 *  adds various functions:
 *     MySQLquery(query) 
 *        Returns the number of rows in query.
 *     MySQLstatus()
 *        Returns the current server status:
 *        Uptime in seconds and the number of running threads,
 *        questions, reloads, and open tables.
 *
 */

#include "config.h"
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "debug.h"
#include "plugin.h"
#include "cfg.h"

#ifdef HAVE_MYSQL_MYSQL_H
#include <mysql/mysql.h>
#else
#warning mysql/mysql.h not found: plugin deactivated
#endif

#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif


#ifdef HAVE_MYSQL_MYSQL_H
static MYSQL conex;

static char Section[] = "Plugin:MySQL";


static int configure_mysql (void)
{
  static int configured = 0;

  char server[256];
  unsigned int port;
  char user[128];
  char password[256];
  char database[256];  
  char *s;
    
  if (configured != 0) return configured;

  s = cfg_get (Section, "server", "localhost");
  if (*s=='\0') {
    info ("[MySQL] empty '%s.server' entry from %s, assuming 'localhost'", Section, cfg_source());
    strcpy(server,"localhost"); 
  }
  else strcpy(server,s);
  free(s);
  
  if (cfg_number(Section, "port", 0, 1, 65536, &port)<1) {
    /* using 0 as default port because mysql_real_connect() will convert it to real default one */
    info ("[MySQL] no '%s.port' entry from %s using MySQL's default", Section, cfg_source());
  }
  
  s = cfg_get (Section, "user", "");
  if (*s=='\0') {
    /* If user is NULL or the empty string "", the lcd4linux Unix user is assumed. */
    info ("[MySQL] empty '%s.user' entry from %s, assuming lcd4linux owner", Section, cfg_source());
    strcpy(user,""); 
  }
  else strcpy(user,s);
  free(s);   
  
  s = cfg_get (Section, "password","");
  /* Do not encrypt the password because encryption is handled automatically by the MySQL client API. */  
  if (*s=='\0') {
    info ("[MySQL] empty '%s.password' entry in %s, assuming none", Section, cfg_source());
    strcpy(password,""); 
  }
  else strcpy(password,s);
  free(s);  
  
  s = cfg_get (Section, "database", "");
  if (*s=='\0') {
    error ("[MySQL] no '%s:database' entry from %s, specify one", Section, cfg_source());
    free (s);
    configured = -1;
    return configured;
  }
  strcpy(database,s);
  free(s);  
  
  mysql_init(&conex);
  if (!mysql_real_connect(&conex,server,user,password,database,port,NULL,0)) {
    error( "[MySQL] conection error: %s",mysql_error(&conex));
    configured = -1;
    return configured;
  }

  configured = 1;
  return configured;
}


static void my_MySQLquery (RESULT *result, RESULT *query)
{
  char *q;
  double value;
  MYSQL_RES *res;
  
  if (configure_mysql() < 0) {
    value = -1;
    SetResult(&result, R_NUMBER, &value); 
    return;
  }
  
  q = R2S(query);
  
  /* mysql_ping(MYSQL *mysql) checks whether the connection to the server is working. */
  /* If it has gone down, an automatic reconnection is attempted. */
  mysql_ping(&conex);
  if (mysql_real_query(&conex,q,(unsigned int) strlen(q))) {
    error( "[MySQL] query error: %s",mysql_error(&conex));
    value = -1;
  } else {
    /* We don't use res=mysql_use_result();  because mysql_num_rows() will not */
    /* return the correct value until all the rows in the result set have been retrieved */
    /* with mysql_fetch_row(), so we use res=mysql_store_result(); instead */
    res=mysql_store_result(&conex);   
    value = (double) mysql_num_rows(res);
    mysql_free_result(res);
  }
  
  SetResult(&result, R_NUMBER, &value); 
}


static void my_MySQLstatus (RESULT *result)
{
  char *value = "";
  char *status;
  
  if (configure_mysql > 0) {

    mysql_ping(&conex);
    status=mysql_stat(&conex);
    if (!status) {
      error( "[MySQL] status error: %s",mysql_error(&conex));
      value="error";
    } else {
      value = status;
    }
  }
  
  SetResult(&result, R_STRING, value); 
}


#endif


int plugin_init_mysql (void)
{
#ifdef HAVE_MYSQL_MYSQL_H
  AddFunction ("MySQL::query",  1, my_MySQLquery);
  AddFunction ("MySQL::status", 0, my_MySQLstatus);
#endif
  return 0;
}

void plugin_exit_mysql(void) 
{
#ifdef HAVE_MYSQL_MYSQL_H
  mysql_close(&conex);
#endif
}