/*
 *  hdbc.c
 *
 *  $Id: hdbc.c 2613 1999-06-01 15:32:12Z VZ $
 *
 *  Data source connect object management functions
 *
 *  The iODBC driver manager.
 *  
 *  Copyright (C) 1995 by Ke Jin <kejin@empress.com> 
 *
 *  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.
 */

#include	"config.h"

#include	"isql.h"
#include	"isqlext.h"

#include        "dlproc.h"

#include	"herr.h"
#include	"henv.h"
#include	"hdbc.h"
#include	"hstmt.h"

#include	"itrace.h"
#include	"stdio.h"

extern	RETCODE	_iodbcdm_driverunload();


RETCODE SQL_API 
SQLAllocConnect (
    HENV henv,
    HDBC FAR * phdbc)
{
  GENV_t FAR *genv = (GENV_t FAR *) henv;
  DBC_t FAR *pdbc;

#if (ODBCVER >= 0x0300)
  if (henv == SQL_NULL_HENV || genv->type != SQL_HANDLE_ENV)
#else
  if (henv == SQL_NULL_HENV)
#endif

    {
      return SQL_INVALID_HANDLE;
    }

  if (phdbc == NULL)
    {
      PUSHSQLERR (genv->herr, en_S1009);

      return SQL_ERROR;
    }

  pdbc = (DBC_t FAR *) MEM_ALLOC (sizeof (DBC_t));

  if (pdbc == NULL)
    {
      *phdbc = SQL_NULL_HDBC;

      PUSHSQLERR (genv->herr, en_S1001);

      return SQL_ERROR;
    }

#if (ODBCVER >= 0x0300)
  pdbc->type = SQL_HANDLE_DBC;
#endif

  /* insert this dbc entry into the link list */
  pdbc->next = genv->hdbc;
  genv->hdbc = pdbc;
  pdbc->genv = henv;

  pdbc->henv = SQL_NULL_HENV;
  pdbc->hstmt = SQL_NULL_HSTMT;
  pdbc->herr = SQL_NULL_HERR;
  pdbc->dhdbc = SQL_NULL_HDBC;
  pdbc->state = en_dbc_allocated;
  pdbc->trace = 0;
  pdbc->tstm = NULL;
  pdbc->tfile = NULL;

  /* set connect options to default values */
  pdbc->access_mode = SQL_MODE_DEFAULT;
  pdbc->autocommit = SQL_AUTOCOMMIT_DEFAULT;
  pdbc->current_qualifier = NULL;
  pdbc->login_timeout = 0UL;
  pdbc->odbc_cursors = SQL_CUR_DEFAULT;
  pdbc->packet_size = 0UL;
  pdbc->quiet_mode = (UDWORD) NULL;
  pdbc->txn_isolation = SQL_TXN_READ_UNCOMMITTED;
  pdbc->cb_commit = (SWORD) SQL_CB_DELETE;
  pdbc->cb_rollback = (SWORD) SQL_CB_DELETE;

  *phdbc = (HDBC) pdbc;

  return SQL_SUCCESS;
}


RETCODE SQL_API 
SQLFreeConnect (HDBC hdbc)
{
  GENV_t FAR *genv;
  DBC_t FAR *pdbc = (DBC_t FAR *) hdbc;
  DBC_t FAR *tpdbc;

  if (hdbc == SQL_NULL_HDBC)
    {
      return SQL_INVALID_HANDLE;
    }

  /* check state */
  if (pdbc->state != en_dbc_allocated)
    {
      PUSHSQLERR (pdbc->herr, en_S1010);

      return SQL_ERROR;
    }

  genv = (GENV_t FAR *) pdbc->genv;

  for (tpdbc = (DBC_t FAR *) genv->hdbc;
      tpdbc != NULL;
      tpdbc = tpdbc->next)
    {
      if (pdbc == tpdbc)
	{
	  genv->hdbc = pdbc->next;
	  break;
	}

      if (pdbc == tpdbc->next)
	{
	  tpdbc->next = pdbc->next;
	  break;
	}
    }

  /* free this dbc */
  _iodbcdm_driverunload (pdbc);
  _iodbcdm_freesqlerrlist (pdbc->herr);

  if (pdbc->tfile)
    {
      MEM_FREE (pdbc->tfile);
    }

  SQLSetConnectOption (pdbc, SQL_OPT_TRACE, SQL_OPT_TRACE_OFF);

  MEM_FREE (pdbc);

  return SQL_SUCCESS;
}


RETCODE SQL_API 
SQLSetConnectOption (
    HDBC hdbc,
    UWORD fOption,
    UDWORD vParam)
{
  DBC_t FAR *pdbc = (DBC_t FAR *) hdbc;
  STMT_t FAR *pstmt;
  HPROC hproc = SQL_NULL_HPROC;
  int sqlstat = en_00000;
  RETCODE retcode = SQL_SUCCESS;

  if (hdbc == SQL_NULL_HDBC)
    {
      return SQL_INVALID_HANDLE;
    }

  /* check option */
  if (fOption < SQL_CONN_OPT_MIN || 
	(fOption > SQL_CONN_OPT_MAX && fOption < SQL_CONNECT_OPT_DRVR_START))
    {
      PUSHSQLERR (pdbc->herr, en_S1092);

      return SQL_ERROR;
    }

  /* check state of connection handle */
  switch (pdbc->state)
     {
     case en_dbc_allocated:
       if (fOption == SQL_TRANSLATE_DLL || fOption == SQL_TRANSLATE_OPTION)
	 {
	   /* This two options are only meaningful
	    * for specified driver. So, has to be
	    * set after a dirver has been loaded.
	    */
	   sqlstat = en_08003;
	   break;
	 }

       if (fOption >= SQL_CONNECT_OPT_DRVR_START && pdbc->henv == SQL_NULL_HENV)
	 /* An option only meaningful for drivers
	  * is passed before loading a driver.
	  * We classify this as an invalid option error.
	  * This is not documented by MS SDK guide.
	  */
	 {
	   sqlstat = en_S1092;
	   break;
	 }
       break;

     case en_dbc_needdata:
       sqlstat = en_S1010;
       break;

     case en_dbc_connected:
     case en_dbc_hstmt:
       if (fOption == SQL_ODBC_CURSORS)
	 {
	   sqlstat = en_08002;
	 }
       break;

     default:
       break;
     }

  /* check state of statement handle(s) */
  for (pstmt = (STMT_t FAR *) pdbc->hstmt;
      pstmt != NULL && sqlstat == en_00000;
      pstmt = (STMT_t FAR *) pstmt->next)
    {
      if (pstmt->state >= en_stmt_needdata || pstmt->asyn_on != en_NullProc)
	{
	  sqlstat = en_S1010;
	}
    }

  if (sqlstat != en_00000)
    {
      PUSHSQLERR (pdbc->herr, sqlstat);

      return SQL_ERROR;
    }

  if (fOption == SQL_OPT_TRACE)
    /* tracing flag can be set before and after connect 
     * and only meaningful for driver manager(actually
     * there is only one tracing file under one global
     * environment).
     */
    {
      switch (vParam)
	 {
	 case SQL_OPT_TRACE_ON:
	   if (pdbc->tfile == NULL)
	     {
	       pdbc->tfile = (char FAR *) MEM_ALLOC (1 +
		   STRLEN (SQL_OPT_TRACE_FILE_DEFAULT));

	       if (pdbc->tfile == NULL)
		 {
		   PUSHSQLERR (pdbc->herr, en_S1001);

		   return SQL_ERROR;
		 }

	       STRCPY (pdbc->tfile, SQL_OPT_TRACE_FILE_DEFAULT);
	     }

	   if (pdbc->tstm == NULL)
	     {

#if	defined(stderr) && defined(stdout)
	       if (STREQ (pdbc->tfile, "stderr"))
		 {
		   pdbc->tstm = stderr;
		 }
	       else if (STREQ (pdbc->tfile, "stdout"))
		 {
		   pdbc->tstm = stdout;
		 }
	       else
#endif

		 {
		   pdbc->tstm
		       = fopen (pdbc->tfile, "a+");
		 }

	       if (pdbc->tstm)
		 {
		   pdbc->trace = 1;
		 }
	       else
		 {
		   pdbc->trace = 0;

		   sqlstat = en_IM013;
		   retcode = SQL_ERROR;
		 }
	     }
	   break;

	 case SQL_OPT_TRACE_OFF:
	   if (pdbc->trace && pdbc->tstm)
	     {

#if	defined(stderr) && defined(stdout)
	       if (stderr != (FILE FAR *) (pdbc->tstm)
		   && stdout != (FILE FAR *) (pdbc->tstm))
#endif

		 {
		   fclose (pdbc->tstm);
		 }
	     }
	   pdbc->tstm = NULL;
	   pdbc->trace = 0;
	   break;

	 default:
	   PUSHSQLERR (pdbc->herr, en_S1009);
	   retcode = SQL_ERROR;
	 }

      if (sqlstat != en_00000)
	{
	  PUSHSQLERR (pdbc->herr, sqlstat);
	}

      return retcode;
    }

  if (fOption == SQL_OPT_TRACEFILE)
    /* Tracing file can be set before and after connect 
     * and only meaningful for driver manager. 
     */
    {
      if (vParam == 0UL || ((char FAR *) vParam)[0] == 0)
	{
	  PUSHSQLERR (pdbc->herr, en_S1009);

	  return SQL_ERROR;
	}

      if (pdbc->tfile && STREQ (pdbc->tfile, vParam))
	{
	  return SQL_SUCCESS;
	}

      if (pdbc->trace)
	{
	  PUSHSQLERR (pdbc->herr, en_IM014);

	  return SQL_ERROR;
	}

      if (pdbc->tfile)
	{
	  MEM_FREE (pdbc->tfile);
	}

      pdbc->tfile = (char FAR *) MEM_ALLOC (1 + STRLEN (vParam));

      if (pdbc->tfile == NULL)
	{
	  PUSHSQLERR (pdbc->herr, en_S1001);

	  return SQL_ERROR;
	}

      STRCPY (pdbc->tfile, vParam);

      return SQL_SUCCESS;
    }

  if (pdbc->state != en_dbc_allocated)
    {
      /* If already connected, then, driver's odbc call
       * will be invoked. Otherwise, we only save the options
       * and delay the setting process until the connection 
       * been established.  
       */
      hproc = _iodbcdm_getproc (hdbc, en_SetConnectOption);

      if (hproc == SQL_NULL_HPROC)
	{
	  PUSHSQLERR (pdbc->herr, en_IM001);

	  return SQL_ERROR;
	}

      CALL_DRIVER (hdbc, retcode, hproc, en_SetConnectOption, 
        (pdbc->dhdbc, fOption, vParam))

      if (retcode != SQL_SUCCESS && retcode != SQL_SUCCESS_WITH_INFO)
	{
	  return retcode;
	}
    }

  /* 
   * Now, either driver's odbc call was successed or
   * driver has not been loaded yet. In the first case, we
   * need flip flag for(such as access_mode, autocommit, ...)
   * for our finit state machine. While in the second case, 
   * we need save option values(such as current_qualifier, ...)
   * for delaied setting. So, ...
   */

  /* No matter what state we are(i.e. allocated or connected, ..)
   * we need to flip the flag.
   */
  switch (fOption)
     {
     case SQL_ACCESS_MODE:
       pdbc->access_mode = vParam;
       break;

     case SQL_AUTOCOMMIT:
       pdbc->autocommit = vParam;
       break;
     }

  /* state transition */
  if (pdbc->state != en_dbc_allocated)
    {
      return retcode;
    }

  /* Only 'allocated' state is possible here, and we need to
   * save the options for delaied setting.
   */
  switch (fOption)
     {
     case SQL_CURRENT_QUALIFIER:
       if (pdbc->current_qualifier != NULL)
	 {
	   MEM_FREE (pdbc->current_qualifier);
	 }

       if (vParam == 0UL)
	 {
	   pdbc->current_qualifier = NULL;

	   break;
	 }

       pdbc->current_qualifier
	   = (char FAR *) MEM_ALLOC (
	   STRLEN (vParam) + 1);

       if (pdbc->current_qualifier == NULL)
	 {
	   PUSHSQLERR (pdbc->herr, en_S1001);
	   return SQL_ERROR;
	 }

       STRCPY (pdbc->current_qualifier, vParam);
       break;

     case SQL_LOGIN_TIMEOUT:
       pdbc->login_timeout = vParam;
       break;

     case SQL_ODBC_CURSORS:
       pdbc->odbc_cursors = vParam;
       break;

     case SQL_PACKET_SIZE:
       pdbc->packet_size = vParam;
       break;

     case SQL_QUIET_MODE:
       pdbc->quiet_mode = vParam;
       break;

     case SQL_TXN_ISOLATION:
       pdbc->txn_isolation = vParam;
       break;

     default:
       /* Since we didn't save the option value for delaied
        * setting, we should raise an error here.
        */
       break;
     }

  return retcode;
}


RETCODE SQL_API 
SQLGetConnectOption (
    HDBC hdbc,
    UWORD fOption,
    PTR pvParam)
{
  DBC_t FAR *pdbc = (DBC_t FAR *) hdbc;
  int sqlstat = en_00000;
  HPROC hproc = SQL_NULL_HPROC;
  RETCODE retcode;

  if (hdbc == SQL_NULL_HDBC)
    {
      return SQL_INVALID_HANDLE;
    }

  /* check option */
  if (fOption < SQL_CONN_OPT_MIN || 
	(fOption > SQL_CONN_OPT_MAX && fOption < SQL_CONNECT_OPT_DRVR_START))
    {
      PUSHSQLERR (pdbc->herr, en_S1092);

      return SQL_ERROR;
    }

  /* check state */
  switch (pdbc->state)
     {
     case en_dbc_allocated:
       if (fOption != SQL_ACCESS_MODE
	   && fOption != SQL_AUTOCOMMIT
	   && fOption != SQL_LOGIN_TIMEOUT
	   && fOption != SQL_OPT_TRACE
	   && fOption != SQL_OPT_TRACEFILE)
	 {
	   sqlstat = en_08003;
	 }
       /* MS ODBC SDK document only
        * allows SQL_ACCESS_MODE
        * and SQL_AUTOCOMMIT in this
        * dbc state. We allow another 
        * two options, because they 
        * are only meaningful for driver 
        * manager.  
        */
       break;

     case en_dbc_needdata:
       sqlstat = en_S1010;
       break;

     default:
       break;
     }

  if (sqlstat != en_00000)
    {
      PUSHSQLERR (pdbc->herr, sqlstat);

      return SQL_ERROR;
    }

  /* Tracing and tracing file options are only 
   * meaningful for driver manager
   */
  if (fOption == SQL_OPT_TRACE)
    {
      if (pdbc->trace)
	*((UDWORD *) pvParam) = (UDWORD) SQL_OPT_TRACE_ON;
      else
	*((UDWORD *) pvParam) = (UDWORD) SQL_OPT_TRACE_OFF;

      return SQL_SUCCESS;
    }

  if (fOption == SQL_OPT_TRACEFILE)
    {
      STRCPY (pvParam, pdbc->tfile);

      return SQL_ERROR;
    }

  if (pdbc->state != en_dbc_allocated)
    /* if already connected, we will invoke driver's function */
    {
      hproc = _iodbcdm_getproc (hdbc, en_GetConnectOption);

      if (hproc == SQL_NULL_HPROC)
	{
	  PUSHSQLERR (pdbc->herr, en_IM001);

	  return SQL_ERROR;
	}

      CALL_DRIVER (hdbc, retcode, hproc, en_GetConnectOption,
	(pdbc->dhdbc, fOption, pvParam))

      return retcode;
    }

  /* We needn't to handle options which are not allowed 
   * to be *get* at a allocated dbc state(and two tracing
   * options which has been handled and returned). Thus, 
   * there are only two possible cases. 
   */
  switch (fOption)
     {
     case SQL_ACCESS_MODE:
       *((UDWORD *) pvParam) = pdbc->access_mode;
       break;

     case SQL_AUTOCOMMIT:
       *((UDWORD *) pvParam) = pdbc->autocommit;
       break;

     case SQL_LOGIN_TIMEOUT:
       *((UDWORD *) pvParam) = pdbc->login_timeout;
       break;

     default:
       break;
     }

  return SQL_SUCCESS;
}


static RETCODE 
_iodbcdm_transact (
    HDBC hdbc,
    UWORD fType)
{
  DBC_t FAR *pdbc = (DBC_t FAR *) hdbc;
  STMT_t FAR *pstmt;
  HPROC hproc;
  RETCODE retcode;

  /* check state */
  switch (pdbc->state)
     {
     case en_dbc_allocated:
     case en_dbc_needdata:
       PUSHSQLERR (pdbc->herr, en_08003);
       return SQL_ERROR;

     case en_dbc_connected:
       return SQL_SUCCESS;

     case en_dbc_hstmt:
     default:
       break;
     }

  for (pstmt = (STMT_t FAR *) (pdbc->hstmt);
      pstmt != NULL;
      pstmt = pstmt->next)
    {
      if (pstmt->state >= en_stmt_needdata
	  || pstmt->asyn_on != en_NullProc)
	{
	  PUSHSQLERR (pdbc->herr, en_S1010);

	  return SQL_ERROR;
	}
    }

  hproc = _iodbcdm_getproc (hdbc, en_Transact);

  if (hproc == SQL_NULL_HPROC)
    {
      PUSHSQLERR (pdbc->herr, en_IM001);

      return SQL_ERROR;
    }

  CALL_DRIVER (hdbc, retcode, hproc, en_Transact,
    (SQL_NULL_HENV, pdbc->dhdbc, fType))

  /* state transition */
  if (retcode != SQL_SUCCESS && retcode != SQL_SUCCESS_WITH_INFO)
    {
      return retcode;
    }

  pdbc->state = en_dbc_hstmt;

  for (pstmt = (STMT_t FAR *) (pdbc->hstmt);
      pstmt != NULL;
      pstmt = pstmt->next)
    {
      switch (pstmt->state)
	 {
	 case en_stmt_prepared:
	   if (pdbc->cb_commit == SQL_CB_DELETE
	       || pdbc->cb_rollback == SQL_CB_DELETE)
	     {
	       pstmt->state = en_stmt_allocated;
	       pstmt->prep_state = 0;
	       break;
	     }
	   break;

	 case en_stmt_executed:
	 case en_stmt_cursoropen:
	 case en_stmt_fetched:
	 case en_stmt_xfetched:
	   if (!pstmt->prep_state
	       && pdbc->cb_commit != SQL_CB_PRESERVE
	       && pdbc->cb_rollback != SQL_CB_PRESERVE)
	     {
	       pstmt->state = en_stmt_allocated;
	       pstmt->prep_state = 0;
	       pstmt->cursor_state = en_stmt_cursor_no;
	       break;
	     }

	   if (pstmt->prep_state)
	     {
	       if (pdbc->cb_commit == SQL_CB_DELETE
		   || pdbc->cb_rollback == SQL_CB_DELETE)
		 {
		   pstmt->state = en_stmt_allocated;
		   pstmt->prep_state = 0;
		   pstmt->cursor_state = en_stmt_cursor_no;
		   break;
		 }

	       if (pdbc->cb_commit == SQL_CB_CLOSE
		   || pdbc->cb_rollback == SQL_CB_CLOSE)
		 {
		   pstmt->state
		       = en_stmt_prepared;
		   pstmt->cursor_state
		       = en_stmt_cursor_no;
		   break;
		 }
	       break;
	     }
	   break;

	 default:
	   break;
	 }
    }

  return retcode;
}


RETCODE SQL_API 
SQLTransact (
    HENV henv,
    HDBC hdbc,
    UWORD fType)
{
  GENV_t FAR *genv = (GENV_t FAR *) henv;
  DBC_t FAR *pdbc = (DBC_t FAR *) hdbc;
  HERR herr;
  RETCODE retcode = 0;

  if (hdbc != SQL_NULL_HDBC)
    {
      herr = pdbc->herr;
    }
  else if (henv != SQL_NULL_HENV)
    {
      herr = genv->herr;
    }
  else
    {
      return SQL_INVALID_HANDLE;
    }

  /* check argument */
  if (fType != SQL_COMMIT
      && fType != SQL_ROLLBACK)
    {
      PUSHSQLERR (herr, en_S1012);

      return SQL_ERROR;
    }

  if (hdbc != SQL_NULL_HDBC)
    {
      retcode = _iodbcdm_transact (hdbc, fType);
    }
  else
    {
      for (pdbc = (DBC_t FAR *) (genv->hdbc);
	  pdbc != NULL;
	  pdbc = pdbc->next)
	{
	  retcode |= _iodbcdm_transact (hdbc, fType);
	}
    }

  if (retcode != SQL_SUCCESS
      && retcode != SQL_SUCCESS_WITH_INFO)
    {
      /* fail on one of the connection */
      return SQL_ERROR;
    }

  return retcode;
}