/* * henv.h * * $Id: henv.h,v 1.1.1.1 2002/04/08 22:48:10 miner Exp $ * * Environment object management functions * * The iODBC driver manager. * * Copyright (C) 1995 by Ke Jin <kejin@empress.com> * Copyright (C) 1996-2002 by OpenLink Software <iodbc@openlinksw.com> * All Rights Reserved. * * This software is released under the terms of either of the following * licenses: * * - GNU Library General Public License (see LICENSE.LGPL) * - The BSD License (see LICENSE.BSD). * * While not mandated by the BSD license, any patches you make to the * iODBC source code may be contributed back into the iODBC project * at your discretion. Contributions will benefit the Open Source and * Data Access community as a whole. Submissions may be made at: * * http://www.iodbc.org * * * GNU Library Generic Public License Version 2 * ============================================ * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the Free * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * * The BSD License * =============== * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name of OpenLink Software Inc. nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL OPENLINK OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifndef _HENV_H #define _HENV_H #include <iodbc.h> #include <dlproc.h> #include <sql.h> #include <sqlext.h> #include <ithread.h> enum odbcapi_t { en_NullProc = 0 #define FUNCDEF(A, B, C) ,B #include "henv.ci" #undef FUNCDEF , __LAST_API_FUNCTION__ } ; typedef struct { int type; /* must be 1st field */ HERR herr; /* err list */ SQLRETURN rc; HENV henv; /* driver's env list */ HDBC hdbc; /* driver's dbc list */ int state; #if (ODBCVER >= 0x300) SQLINTEGER odbc_ver; /* ODBC version of the application */ #endif SQLSMALLINT err_rec; } GENV_t; typedef struct { HENV next; /* next attached env handle */ int refcount; /* Driver's bookkeeping reference count */ HPROC dllproc_tab[__LAST_API_FUNCTION__]; /* driver api calls */ HENV dhenv; /* driver env handle */ HDLL hdll; /* driver share library handle */ SWORD thread_safe; /* Is the driver threadsafe? */ MUTEX_DECLARE (drv_lock); /* Used only when driver is not threadsafe */ #if (ODBCVER >= 0x300) SQLINTEGER dodbc_ver; /* driver's ODBC version */ #endif } ENV_t; #define IS_VALID_HENV(x) \ ((x) != SQL_NULL_HENV && ((GENV_t FAR *)(x))->type == SQL_HANDLE_ENV) /* * Multi threading */ #if defined (IODBC_THREADING) extern SPINLOCK_DECLARE(iodbcdm_global_lock); #define ODBC_LOCK() SPINLOCK_LOCK(iodbcdm_global_lock) #define ODBC_UNLOCK() SPINLOCK_UNLOCK(iodbcdm_global_lock) #else #define ODBC_LOCK() #define ODBC_UNLOCK() #endif /* Note: * * - ODBC applications only know about global environment handle, * a void pointer points to a GENV_t object. There is only one * this object per process(however, to make the library reentrant, * we still keep this object on heap). Applications only know * address of this object and needn't care about its detail. * * - ODBC driver manager knows about instance environment handles, * void pointers point to ENV_t objects. There are maybe more * than one this kind of objects per process. However, multiple * connections to a same data source(i.e. call same share library) * will share one instance environment object. * * - ODBC driver manager knows about their own environment handle, * a void pointer point to a driver defined object. Every driver * keeps one of its own environment object and driver manager * keeps address of it by the 'dhenv' field in the instance * environment object without care about its detail. * * - Applications can get driver's environment object handle by * SQLGetInfo() with fInfoType equals to SQL_DRIVER_HENV */ #endif