serval-dna/asterisk_include/asterisk/res_odbc.h
2011-03-21 13:08:35 +10:30

104 lines
4.1 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 1999 - 2005, Digium, Inc.
* Copyright (C) 2004 - 2005, Anthony Minessale II
* Copyright (C) 2006, Tilghman Lesher
*
* Mark Spencer <markster@digium.com>
* Anthony Minessale <anthmct@yahoo.com>
* Tilghman Lesher <res_odbc_200603@the-tilghman.com>
*
* 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 ODBC resource manager
*/
#ifndef _ASTERISK_RES_ODBC_H
#define _ASTERISK_RES_ODBC_H
#include <sql.h>
#include <sqlext.h>
#include <sqltypes.h>
typedef enum { ODBC_SUCCESS=0, ODBC_FAIL=-1} odbc_status;
struct odbc_obj {
ast_mutex_t lock;
SQLHDBC con; /* ODBC Connection Handle */
struct odbc_class *parent; /* Information about the connection is protected */
struct timeval last_used;
unsigned int used:1;
unsigned int up:1;
AST_LIST_ENTRY(odbc_obj) list;
};
/* functions */
/*! \brief Executes a prepared statement handle
* \param obj The non-NULL result of odbc_request_obj()
* \param stmt The prepared statement handle
* \return Returns 0 on success or -1 on failure
*
* This function was originally designed simply to execute a prepared
* statement handle and to retry if the initial execution failed.
* Unfortunately, it did this by disconnecting and reconnecting the database
* handle which on most databases causes the statement handle to become
* invalid. Therefore, this method has been deprecated in favor of
* odbc_prepare_and_execute() which allows the statement to be prepared
* multiple times, if necessary, in case of a loss of connection.
*
* This function really only ever worked with MySQL, where the statement handle is
* not prepared on the server. If you are not using MySQL, you should avoid it.
*/
int ast_odbc_smart_execute(struct odbc_obj *obj, SQLHSTMT stmt) __attribute__((deprecated));
/*! \brief Retrieves a connected ODBC object
* \param name The name of the ODBC class for which a connection is needed.
* \param check Whether to ensure that a connection is valid before returning the handle. Usually unnecessary.
* \return Returns an ODBC object or NULL if there is no connection available with the requested name.
*
* Connection classes may, in fact, contain multiple connection handles. If
* the connection is pooled, then each connection will be dedicated to the
* thread which requests it. Note that all connections should be released
* when the thread is done by calling odbc_release_obj(), below.
*/
struct odbc_obj *ast_odbc_request_obj(const char *name, int check);
/*! \brief Releases an ODBC object previously allocated by odbc_request_obj()
* \param obj The ODBC object
*/
void ast_odbc_release_obj(struct odbc_obj *obj);
/*! \brief Checks an ODBC object to ensure it is still connected
* \param obj The ODBC object
* \return Returns 0 if connected, -1 otherwise.
*/
int ast_odbc_sanity_check(struct odbc_obj *obj);
/*! \brief Checks if the database natively supports backslash as an escape character.
* \param obj The ODBC object
* \return Returns 1 if backslash is a native escape character, 0 if an ESCAPE clause is needed to support '\'
*/
int ast_odbc_backslash_is_escape(struct odbc_obj *obj);
/*! \brief Prepares, executes, and returns the resulting statement handle.
* \param obj The ODBC object
* \param prepare_cb A function callback, which, when called, should return a statement handle prepared, with any necessary parameters or result columns bound.
* \param data A parameter to be passed to the prepare_cb parameter function, indicating which statement handle is to be prepared.
* \return Returns a statement handle or NULL on error.
*/
SQLHSTMT ast_odbc_prepare_and_execute(struct odbc_obj *obj, SQLHSTMT (*prepare_cb)(struct odbc_obj *obj, void *data), void *data);
#endif /* _ASTERISK_RES_ODBC_H */