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  • /*
     * Asterisk -- An open source telephony toolkit.
     *
     * Copyright (C) 2004, Constantine Filin and Christos Ricudis
     *
     * Christos Ricudis <ricudis@itc.auth.gr>
     * Constantine Filin <cf@intermedia.net>
     *
     * See http://www.asterisk.org for more information about
     * the Asterisk project. Please do not directly contact
     * any of the maintainers of this project for assistance;
     * the project provides a web site, mailing lists and IRC
     * channels for your use.
     *
     * This program is free software, distributed under the terms of
     * the GNU General Public License Version 2. See the LICENSE file
     * at the top of the source tree.
     */
    
    /*!
     * \file
     * \brief MYSQL dialplan application
     * \ingroup applications
     */
    
    
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    /*! \li \ref app_mysql.c uses the configuration file \ref app_mysql.conf
    
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     * \addtogroup configuration_file Configuration Files
     */
    
    /*! 
     * \page app_mysql.conf app_mysql.conf
     * \verbinclude app_mysql.conf.sample
     */
    
    
    /*** MODULEINFO
    	<depend>mysqlclient</depend>
    	<defaultenabled>no</defaultenabled>
    
    	<support_level>deprecated</support_level>
    	<replacement>func_odbc</replacement>
    
     ***/
    
    #include "asterisk.h"
    
    #include <mysql/mysql.h>
    
    #include "asterisk/file.h"
    #include "asterisk/logger.h"
    #include "asterisk/channel.h"
    #include "asterisk/pbx.h"
    #include "asterisk/module.h"
    #include "asterisk/linkedlists.h"
    #include "asterisk/chanvars.h"
    #include "asterisk/lock.h"
    #include "asterisk/options.h"
    #include "asterisk/app.h"
    #include "asterisk/config.h"
    
    #define EXTRA_LOG 0
    
    enum { NULLSTRING, NULLVALUE, EMPTYSTRING } nullvalue = NULLSTRING;
    
    static const char app[] = "MYSQL";
    
    static const char synopsis[] = "Do several mySQLy things";
    
    static const char descrip[] =
    "MYSQL():  Do several mySQLy things\n"
    "Syntax:\n"
    "  MYSQL(Set timeout <num>)\n"
    "    Set the connection timeout, in seconds.\n"
    
    "  MYSQL(Connect connid dhhost[:dbport] dbuser dbpass dbname [dbcharset])\n"
    
    "    Connects to a database.  Arguments contain standard MySQL parameters\n"
    
    "    passed to function mysql_real_connect.  Optional parameter dbcharset\n"
    "    defaults to 'latin1'.  Connection identifer returned in ${connid}\n"
    
    "  MYSQL(Query resultid ${connid} query-string)\n"
    "    Executes standard MySQL query contained in query-string using established\n"
    "    connection identified by ${connid}. Result of query is stored in ${resultid}.\n"
    "  MYSQL(Nextresult resultid ${connid}\n"
    "    If last query returned more than one result set, it stores the next\n"
    "    result set in ${resultid}. It's useful with stored procedures\n"
    "  MYSQL(Fetch fetchid ${resultid} var1 var2 ... varN)\n"
    "    Fetches a single row from a result set contained in ${result_identifier}.\n"
    "    Assigns returned fields to ${var1} ... ${varn}.  ${fetchid} is set TRUE\n"
    "    if additional rows exist in result set.\n"
    "  MYSQL(Clear ${resultid})\n"
    "    Frees memory and datastructures associated with result set.\n"
    "  MYSQL(Disconnect ${connid})\n"
    "    Disconnects from named connection to MySQL.\n"
    "  On exit, always returns 0. Sets MYSQL_STATUS to 0 on success and -1 on error.\n";
    
    /*
    EXAMPLES OF USE :
    
    
    exten => s,2,MYSQL(Connect connid localhost asterisk mypass credit utf8)
    
    exten => s,3,MYSQL(Query resultid ${connid} SELECT username,credit FROM credit WHERE callerid=${CALLERIDNUM})
    exten => s,4,MYSQL(Fetch fetchid ${resultid} datavar1 datavar2)
    exten => s,5,GotoIf(${fetchid}?6:8)
    exten => s,6,Festival("User ${datavar1} currently has credit balance of ${datavar2} dollars.")
    exten => s,7,Goto(s,4)
    exten => s,8,MYSQL(Clear ${resultid})
    exten => s,9,MYSQL(Disconnect ${connid})
    */
    
    AST_MUTEX_DEFINE_STATIC(_mysql_mutex);
    
    
    #define MYSQL_CONFIG "app_mysql.conf"
    #define MYSQL_CONFIG_OLD "mysql.conf"
    
    #define AST_MYSQL_ID_DUMMY   0
    #define AST_MYSQL_ID_CONNID  1
    #define AST_MYSQL_ID_RESID   2
    #define AST_MYSQL_ID_FETCHID 3
    
    static int autoclear = 0;
    
    static void mysql_ds_destroy(void *data);
    static void mysql_ds_fixup(void *data, struct ast_channel *oldchan, struct ast_channel *newchan);
    
    
    static const struct ast_datastore_info mysql_ds_info = {
    
    	.type = "APP_ADDON_SQL_MYSQL",
    	.destroy = mysql_ds_destroy,
    	.chan_fixup = mysql_ds_fixup,
    };
    
    struct ast_MYSQL_id {
    	struct ast_channel *owner;
    	int identifier_type; /* 0=dummy, 1=connid, 2=resultid */
    	int identifier;
    	void *data;
    	AST_LIST_ENTRY(ast_MYSQL_id) entries;
    } *ast_MYSQL_id;
    
    AST_LIST_HEAD(MYSQLidshead,ast_MYSQL_id) _mysql_ids_head;
    
    static void mysql_ds_destroy(void *data)
    {
    	/* Destroy any IDs owned by the channel */
    	struct ast_MYSQL_id *i;
    	if (AST_LIST_LOCK(&_mysql_ids_head)) {
    		ast_log(LOG_WARNING, "Unable to lock identifiers list\n");
    	} else {
    		AST_LIST_TRAVERSE_SAFE_BEGIN(&_mysql_ids_head, i, entries) {
    			if (i->owner == data) {
    				AST_LIST_REMOVE_CURRENT(entries);
    				if (i->identifier_type == AST_MYSQL_ID_CONNID) {
    					/* Drop connection */
    					mysql_close(i->data);
    				} else if (i->identifier_type == AST_MYSQL_ID_RESID) {
    					/* Drop result */
    					mysql_free_result(i->data);
    				}
    				ast_free(i);
    			}
    		}
    		AST_LIST_TRAVERSE_SAFE_END
    		AST_LIST_UNLOCK(&_mysql_ids_head);
    	}
    }
    
    static void mysql_ds_fixup(void *data, struct ast_channel *oldchan, struct ast_channel *newchan)
    {
    	/* Destroy any IDs owned by the channel */
    	struct ast_MYSQL_id *i;
    	if (AST_LIST_LOCK(&_mysql_ids_head)) {
    		ast_log(LOG_WARNING, "Unable to lock identifiers list\n");
    	} else {
    		AST_LIST_TRAVERSE_SAFE_BEGIN(&_mysql_ids_head, i, entries) {
    			if (i->owner == data) {
    				AST_LIST_REMOVE_CURRENT(entries);
    				if (i->identifier_type == AST_MYSQL_ID_CONNID) {
    					/* Drop connection */
    					mysql_close(i->data);
    				} else if (i->identifier_type == AST_MYSQL_ID_RESID) {
    					/* Drop result */
    					mysql_free_result(i->data);
    				}
    				ast_free(i);
    			}
    		}
    		AST_LIST_TRAVERSE_SAFE_END
    		AST_LIST_UNLOCK(&_mysql_ids_head);
    	}
    }
    
    /* helpful procs */
    static void *find_identifier(int identifier, int identifier_type)
    {
    	struct MYSQLidshead *headp = &_mysql_ids_head;
    	struct ast_MYSQL_id *i;
    	void *res=NULL;
    	int found=0;
    
    	if (AST_LIST_LOCK(headp)) {
    		ast_log(LOG_WARNING, "Unable to lock identifiers list\n");
    	} else {
    		AST_LIST_TRAVERSE(headp, i, entries) {
    			if ((i->identifier == identifier) && (i->identifier_type == identifier_type)) {
    				found = 1;
    				res = i->data;
    				break;
    			}
    		}
    		if (!found) {
    			ast_log(LOG_WARNING, "Identifier %d, identifier_type %d not found in identifier list\n", identifier, identifier_type);
    		}
    		AST_LIST_UNLOCK(headp);
    	}
    
    	return res;
    }
    
    static int add_identifier(struct ast_channel *chan, int identifier_type, void *data)
    {
    	struct ast_MYSQL_id *i = NULL, *j = NULL;
    	struct MYSQLidshead *headp = &_mysql_ids_head;
    	int maxidentifier = 0;
    
    	if (AST_LIST_LOCK(headp)) {
    		ast_log(LOG_WARNING, "Unable to lock identifiers list\n");
    		return -1;
    	} else {
    		i = malloc(sizeof(*i));
    		AST_LIST_TRAVERSE(headp, j, entries) {
    			if (j->identifier > maxidentifier) {
    				maxidentifier = j->identifier;
    			}
    		}
    		i->identifier = maxidentifier + 1;
    		i->identifier_type = identifier_type;
    		i->data = data;
    		i->owner = chan;
    		AST_LIST_INSERT_HEAD(headp, i, entries);
    		AST_LIST_UNLOCK(headp);
    	}
    	return i->identifier;
    }
    
    static int del_identifier(int identifier, int identifier_type)
    {
    	struct ast_MYSQL_id *i;
    	struct MYSQLidshead *headp = &_mysql_ids_head;
    	int found = 0;
    
    	if (AST_LIST_LOCK(headp)) {
    		ast_log(LOG_WARNING, "Unable to lock identifiers list\n");
    	} else {
    		AST_LIST_TRAVERSE(headp, i, entries) {
    			if ((i->identifier == identifier) &&
    			    (i->identifier_type == identifier_type)) {
    				AST_LIST_REMOVE(headp, i, entries);
    				free(i);
    				found = 1;
    				break;
    			}
    		}
    		AST_LIST_UNLOCK(headp);
    	}
    
    	if (found == 0) {
    		ast_log(LOG_WARNING, "Could not find identifier %d, identifier_type %d in list to delete\n", identifier, identifier_type);
    		return -1;
    	} else {
    		return 0;
    	}
    }
    
    static int set_asterisk_int(struct ast_channel *chan, char *varname, int id)
    {
    	if (id >= 0) {
    		char s[12] = "";
    		snprintf(s, sizeof(s), "%d", id);
    		ast_debug(5, "MYSQL: setting var '%s' to value '%s'\n", varname, s);
    		pbx_builtin_setvar_helper(chan, varname, s);
    	}
    	return id;
    }
    
    static int add_identifier_and_set_asterisk_int(struct ast_channel *chan, char *varname, int identifier_type, void *data)
    {
    	return set_asterisk_int(chan, varname, add_identifier(chan, identifier_type, data));
    }
    
    static int safe_scan_int(char **data, char *delim, int def)
    {
    	char *end;
    	int res = def;
    	char *s = strsep(data, delim);
    	if (s) {
    		res = strtol(s, &end, 10);
    		if (*end)
    			res = def;  /* not an integer */
    	}
    	return res;
    }
    
    
    static int aMYSQL_set(struct ast_channel *chan, const char *data)
    
    	AST_DECLARE_APP_ARGS(args,
    		AST_APP_ARG(set);
    		AST_APP_ARG(variable);
    		AST_APP_ARG(value);
    	);
    
    
    	parse = ast_strdupa(data);
    	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
    
    		var = ast_alloca(6 + strlen(args.variable) + 1);
    
    		sprintf(var, "MYSQL_%s", args.variable);
    
    		/* Make the parameter case-insensitive */
    		for (tmp = var + 6; *tmp; tmp++)
    			*tmp = toupper(*tmp);
    
    		pbx_builtin_setvar_helper(chan, var, args.value);
    	}
    	return 0;
    }
    
    /* MYSQL operations */
    
    static int aMYSQL_connect(struct ast_channel *chan, const char *data)
    
    {
    	AST_DECLARE_APP_ARGS(args,
    		AST_APP_ARG(connect);
    		AST_APP_ARG(connid);
    		AST_APP_ARG(dbhost);
    		AST_APP_ARG(dbuser);
    		AST_APP_ARG(dbpass);
    		AST_APP_ARG(dbname);
    
    	);
    	MYSQL *mysql;
    	int timeout;
    	const char *ctimeout;
    
    	unsigned int port = 0;
    	char *port_str;
    
    	char *parse = ast_strdupa(data);
     
    	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
    
    		ast_log(LOG_WARNING, "MYSQL_connect is missing some arguments\n");
    		return -1;
    	}
    
    	if (!(mysql = mysql_init(NULL))) {
    		ast_log(LOG_WARNING, "mysql_init returned NULL\n");
    		return -1;
    	}
    
    	ctimeout = pbx_builtin_getvar_helper(chan, "MYSQL_TIMEOUT");
    
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    	if (ctimeout && sscanf(ctimeout, "%30d", &timeout) == 1) {
    
    		mysql_options(mysql, MYSQL_OPT_CONNECT_TIMEOUT, (void *)&timeout);
    	}
    
    	if(args.dbcharset && strlen(args.dbcharset) > 2){
    		char set_names[255];
    		char statement[512];
    		snprintf(set_names, sizeof(set_names), "SET NAMES %s", args.dbcharset);
    		mysql_real_escape_string(mysql, statement, set_names, sizeof(set_names));
    		mysql_options(mysql, MYSQL_INIT_COMMAND, set_names);
    		mysql_options(mysql, MYSQL_SET_CHARSET_NAME, args.dbcharset);
    	}
    
    	if ((port_str = strchr(args.dbhost, ':'))) {
    		*port_str++ = '\0';
    		if (sscanf(port_str, "%u", &port) != 1) {
    			ast_log(LOG_WARNING, "Invalid port: '%s'\n", port_str);
    			port = 0;
    		}
    	}
    
    	if (!mysql_real_connect(mysql, args.dbhost, args.dbuser, args.dbpass, args.dbname, port, NULL,
    
    #ifdef CLIENT_MULTI_STATEMENTS
    			CLIENT_MULTI_STATEMENTS | CLIENT_MULTI_RESULTS
    #elif defined(CLIENT_MULTI_QUERIES)
    			CLIENT_MULTI_QUERIES
    #else
    			0
    #endif
    		)) {
    		ast_log(LOG_WARNING, "mysql_real_connect(mysql,%s,%s,dbpass,%s,...) failed(%d): %s\n",
    				args.dbhost, args.dbuser, args.dbname, mysql_errno(mysql), mysql_error(mysql));
    		return -1;
    	}
    
    	add_identifier_and_set_asterisk_int(chan, args.connid, AST_MYSQL_ID_CONNID, mysql);
    	return 0;
    }
    
    
    static int aMYSQL_query(struct ast_channel *chan, const char *data)
    
    {
    	AST_DECLARE_APP_ARGS(args,
    		AST_APP_ARG(query);
    		AST_APP_ARG(resultid);
    		AST_APP_ARG(connid);
    		AST_APP_ARG(sql);
    	);
    	MYSQL       *mysql;
    	MYSQL_RES   *mysqlres;
    	int connid;
    	int mysql_query_res;
    
    	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
    
    
    	if (args.argc != 4 || (connid = atoi(args.connid)) == 0) {
    		ast_log(LOG_WARNING, "missing some arguments\n");
    		return -1;
    	}
    
    	if (!(mysql = find_identifier(connid, AST_MYSQL_ID_CONNID))) {
    		ast_log(LOG_WARNING, "Invalid connection identifier %s passed in aMYSQL_query\n", args.connid);
    		return -1;
    	}
    
    	if ((mysql_query_res = mysql_query(mysql, args.sql)) != 0) {
    		ast_log(LOG_WARNING, "aMYSQL_query: mysql_query failed. Error: %s\n", mysql_error(mysql));
    		return -1;
    	}
    
    	if ((mysqlres = mysql_store_result(mysql))) {
    		add_identifier_and_set_asterisk_int(chan, args.resultid, AST_MYSQL_ID_RESID, mysqlres);
    		return 0;
    	} else if (!mysql_field_count(mysql)) {
    		return 0;
    	} else
    		ast_log(LOG_WARNING, "mysql_store_result() failed on query %s\n", args.sql);
    
    	return -1;
    }
    
    
    static int aMYSQL_nextresult(struct ast_channel *chan, const char *data)
    
    {
    	MYSQL       *mysql;
    	MYSQL_RES   *mysqlres;
    	AST_DECLARE_APP_ARGS(args,
    		AST_APP_ARG(nextresult);
    		AST_APP_ARG(resultid);
    		AST_APP_ARG(connid);
    	);
    	int connid = -1;
    
    	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
    
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    	sscanf(args.connid, "%30d", &connid);
    
    
    	if (args.argc != 3 || connid <= 0) {
    		ast_log(LOG_WARNING, "missing some arguments\n");
    		return -1;
    	}
    
    	if (!(mysql = find_identifier(connid, AST_MYSQL_ID_CONNID))) {
    		ast_log(LOG_WARNING, "Invalid connection identifier %d passed in aMYSQL_query\n", connid);
    		return -1;
    	}
    
    	if (mysql_more_results(mysql)) {
    		mysql_next_result(mysql);
    		if ((mysqlres = mysql_store_result(mysql))) {
    			add_identifier_and_set_asterisk_int(chan, args.resultid, AST_MYSQL_ID_RESID, mysqlres);
    			return 0;
    		} else if (!mysql_field_count(mysql)) {
    			return 0;
    		} else
    			ast_log(LOG_WARNING, "mysql_store_result() failed on storing next_result\n");
    	} else
    		ast_log(LOG_WARNING, "mysql_more_results() result set has no more results\n");
    
    	return 0;
    }
    
    
    
    static int aMYSQL_fetch(struct ast_channel *chan, const char *data)
    
    {
    	MYSQL_RES *mysqlres;
    	MYSQL_ROW mysqlrow;
    	AST_DECLARE_APP_ARGS(args,
    		AST_APP_ARG(fetch);
    		AST_APP_ARG(resultvar);
    		AST_APP_ARG(fetchid);
    		AST_APP_ARG(vars);
    	);
    	char *s5, *parse;
    	int resultid = -1, numFields, j;
    
    	parse = ast_strdupa(data);
    	AST_NONSTANDARD_APP_ARGS(args, parse, ' ');
    
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    	sscanf(args.fetchid, "%30d", &resultid);
    
    
    	if (args.resultvar && (resultid >= 0) ) {
    		if ((mysqlres = find_identifier(resultid, AST_MYSQL_ID_RESID)) != NULL) {
    			/* Grab the next row */
    			if ((mysqlrow = mysql_fetch_row(mysqlres)) != NULL) {
    				numFields = mysql_num_fields(mysqlres);
    				for (j = 0; j < numFields; j++) {
    					s5 = strsep(&args.vars, " ");
    					if (s5 == NULL) {
    						ast_log(LOG_WARNING, "ast_MYSQL_fetch: More fields (%d) than variables (%d)\n", numFields, j);
    						break;
    					}
    
    					pbx_builtin_setvar_helper(chan, s5, mysqlrow[j] ? mysqlrow[j] :
    						nullvalue == NULLSTRING ? "NULL" :
    						nullvalue == EMPTYSTRING ? "" :
    						NULL);
    				}
    				ast_debug(5, "ast_MYSQL_fetch: numFields=%d\n", numFields);
    				set_asterisk_int(chan, args.resultvar, 1); /* try more rows */
    			} else {
    				ast_debug(5, "ast_MYSQL_fetch : EOF\n");
    				set_asterisk_int(chan, args.resultvar, 0); /* no more rows */
    			}
    			return 0;
    		} else {
    			set_asterisk_int(chan, args.resultvar, 0);
    			ast_log(LOG_WARNING, "aMYSQL_fetch: Invalid result identifier %d passed\n", resultid);
    		}
    	} else {
    		ast_log(LOG_WARNING, "aMYSQL_fetch: missing some arguments\n");
    	}
    
    	return -1;
    }
    
    
    static int aMYSQL_clear(struct ast_channel *chan, const char *data)
    
    	char *parse = ast_strdupa(data);
    	strsep(&parse, " "); /* eat the first token, we already know it :P */
    	id = safe_scan_int(&parse, " \n", -1);
    
    	if ((mysqlres = find_identifier(id, AST_MYSQL_ID_RESID)) == NULL) {
    		ast_log(LOG_WARNING, "Invalid result identifier %d passed in aMYSQL_clear\n", id);
    	} else {
    		mysql_free_result(mysqlres);
    		del_identifier(id, AST_MYSQL_ID_RESID);
    	}
    
    	return 0;
    }
    
    
    static int aMYSQL_disconnect(struct ast_channel *chan, const char *data)
    
    	char *parse = ast_strdupa(data);
    	strsep(&parse, " "); /* eat the first token, we already know it :P */
    
    	id = safe_scan_int(&parse, " \n", -1);
    
    	if ((mysql = find_identifier(id, AST_MYSQL_ID_CONNID)) == NULL) {
    		ast_log(LOG_WARNING, "Invalid connection identifier %d passed in aMYSQL_disconnect\n", id);
    	} else {
    		mysql_close(mysql);
    		del_identifier(id, AST_MYSQL_ID_CONNID);
    	}
    
    	return 0;
    }
    
    static int MYSQL_exec(struct ast_channel *chan, const char *data)
    {
    	int result;
    	char sresult[10];
    
    	ast_debug(5, "MYSQL: data=%s\n", data);
    
    	if (!data) {
    		ast_log(LOG_WARNING, "MYSQL requires an argument (see manual)\n");
    		return -1;
    	}
    
    	result = 0;
    
    	if (autoclear) {
    
    		struct ast_datastore *mysql_store = NULL;
    
    		ast_channel_lock(chan);
    		mysql_store = ast_channel_datastore_find(chan, &mysql_ds_info, NULL);
    
    		if (!mysql_store) {
    			if (!(mysql_store = ast_datastore_alloc(&mysql_ds_info, NULL))) {
    				ast_log(LOG_WARNING, "Unable to allocate new datastore.\n");
    			} else {
    				mysql_store->data = chan;
    				ast_channel_datastore_add(chan, mysql_store);
    			}
    		}
    
    		ast_channel_unlock(chan);
    
    	}
    	ast_mutex_lock(&_mysql_mutex);
    
    	if (strncasecmp("connect", data, strlen("connect")) == 0) {
    
    		result = aMYSQL_connect(chan, data);
    
    	} else if (strncasecmp("query", data, strlen("query")) == 0) {
    
    	} else if (strncasecmp("nextresult", data, strlen("nextresult")) == 0) {
    
    		result = aMYSQL_nextresult(chan, data);
    
    	} else if (strncasecmp("fetch", data, strlen("fetch")) == 0) {
    
    	} else if (strncasecmp("clear", data, strlen("clear")) == 0) {
    
    	} else if (strncasecmp("disconnect", data, strlen("disconnect")) == 0) {
    
    		result = aMYSQL_disconnect(chan, data);
    
    	} else if (strncasecmp("set", data, 3) == 0) {
    
    	} else {
    		ast_log(LOG_WARNING, "Unknown argument to MYSQL application : %s\n", data);
    		result = -1;
    	}
    
    	ast_mutex_unlock(&_mysql_mutex);
    
    	snprintf(sresult, sizeof(sresult), "%d", result);
    	pbx_builtin_setvar_helper(chan, "MYSQL_STATUS", sresult);
    	return 0;
    }
    
    static int unload_module(void)
    {
    	return ast_unregister_application(app);
    }
    
    
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    /*!
     * \brief Load the module
     *
     * Module loading including tests for configuration or dependencies.
     * This function can return AST_MODULE_LOAD_FAILURE, AST_MODULE_LOAD_DECLINE,
     * or AST_MODULE_LOAD_SUCCESS. If a dependency or environment variable fails
     * tests return AST_MODULE_LOAD_FAILURE. If the module can not load the 
     * configuration file or other non-critical problem return 
     * AST_MODULE_LOAD_DECLINE. On success return AST_MODULE_LOAD_SUCCESS.
     */
    
    static int load_module(void)
    {
    	struct MYSQLidshead *headp = &_mysql_ids_head;
    	struct ast_flags config_flags = { 0 };
    	struct ast_config *cfg = ast_config_load(MYSQL_CONFIG, config_flags);
    	const char *temp;
    
    
    	if (!cfg) {
    		/* Backwards compatibility ftw */
    		cfg = ast_config_load(MYSQL_CONFIG_OLD, config_flags);
    	}
    
    
    	if (cfg) {
    		if ((temp = ast_variable_retrieve(cfg, "general", "nullvalue"))) {
    			if (!strcasecmp(temp, "nullstring")) {
    				nullvalue = NULLSTRING;
    			} else if (!strcasecmp(temp, "emptystring")) {
    				nullvalue = EMPTYSTRING;
    			} else if (!strcasecmp(temp, "null")) {
    				nullvalue = NULLVALUE;
    			} else {
    				ast_log(LOG_WARNING, "Illegal value for 'nullvalue': '%s' (must be 'nullstring', 'null', or 'emptystring')\n", temp);
    			}
    		}
    		if ((temp = ast_variable_retrieve(cfg, "general", "autoclear")) && ast_true(temp)) {
    			autoclear = 1;
    		}
    		ast_config_destroy(cfg);
    	}
    
    	AST_LIST_HEAD_INIT(headp);
    	return ast_register_application(app, MYSQL_exec, synopsis, descrip);
    }
    
    AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Simple Mysql Interface");