Line data    Source code

       1             : /*
       2             :  * SPDX-License-Identifier: MPL-2.0
       3             :  *
       4             :  * This Source Code Form is subject to the terms of the Mozilla Public
       5             :  * License, v. 2.0.  If a copy of the MPL was not distributed with this
       6             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
       7             :  *
       8             :  * Copyright 2024 MonetDB Foundation;
       9             :  * Copyright August 2008 - 2023 MonetDB B.V.;
      10             :  * Copyright 1997 - July 2008 CWI.
      11             :  */
      12             : 
      13             : /*
      14             :  * This code was created by Peter Harvey (mostly during Christmas 98/99).
      15             :  * This code is LGPL. Please ensure that this message remains in future
      16             :  * distributions and uses of this code (that's about all I get out of it).
      17             :  * - Peter Harvey pharvey@codebydesign.com
      18             :  *
      19             :  * This file has been modified for the MonetDB project.  See the file
      20             :  * Copyright in this directory for more information.
      21             :  */
      22             : 
      23             : /*****************************************************************************
      24             :  * SQLFetchScroll()
      25             :  * CLI Compliance: ISO 92
      26             :  *
      27             :  * Author: Martin van Dinther, Sjoerd Mullender
      28             :  * Date  : 30 aug 2002
      29             :  *
      30             :  *****************************************************************************/
      31             : 
      32             : #include "ODBCGlobal.h"
      33             : #include "ODBCStmt.h"
      34             : 
      35             : 
      36             : SQLRETURN
      37        1001 : MNDBFetchScroll(ODBCStmt *stmt,
      38             :                 SQLSMALLINT FetchOrientation,
      39             :                 SQLLEN FetchOffset,
      40             :                 SQLUSMALLINT *RowStatusArray)
      41             : {
      42        1001 :         assert(stmt->hdl);
      43             : 
      44        1001 :         if ((stmt->cursorType == SQL_CURSOR_FORWARD_ONLY ||
      45        1001 :              stmt->cursorScrollable == SQL_NONSCROLLABLE) &&
      46             :             FetchOrientation != SQL_FETCH_NEXT) {
      47             :                 /* Fetch type out of range */
      48           0 :                 addStmtError(stmt, "HY106", NULL, 0);
      49           0 :                 return SQL_ERROR;
      50             :         }
      51             : #define RowSetSize      (stmt->ApplRowDescr->sql_desc_array_size)
      52             : 
      53        1001 :         assert(stmt->startRow >= 0);
      54        1001 :         switch (FetchOrientation) {
      55        1001 :         case SQL_FETCH_NEXT:
      56        1001 :                 stmt->startRow += stmt->rowSetSize;
      57        1001 :                 break;
      58           0 :         case SQL_FETCH_FIRST:
      59           0 :                 stmt->startRow = 0;
      60           0 :                 break;
      61           0 :         case SQL_FETCH_LAST:
      62           0 :                 if (stmt->rowcount < RowSetSize)
      63           0 :                         stmt->startRow = 0;
      64             :                 else
      65           0 :                         stmt->startRow = stmt->rowcount - RowSetSize;
      66             :                 break;
      67           0 :         case SQL_FETCH_PRIOR:
      68           0 :                 if (stmt->startRow == 0) {
      69             :                         /* before start */
      70           0 :                         stmt->startRow = 0;
      71           0 :                         stmt->rowSetSize = 0;
      72           0 :                         stmt->State = FETCHED;
      73           0 :                         return SQL_NO_DATA;
      74             :                 }
      75           0 :                 if (stmt->startRow < (SQLLEN) RowSetSize) {
      76             :                         /* Attempt to fetch before the result set
      77             :                          * returned the first rowset */
      78           0 :                         addStmtError(stmt, "01S06", NULL, 0);
      79           0 :                         stmt->startRow = 0;
      80             :                 } else
      81           0 :                         stmt->startRow = stmt->startRow - RowSetSize;
      82             :                 break;
      83           0 :         case SQL_FETCH_RELATIVE:
      84           0 :                 if ((stmt->startRow > 0 || stmt->rowSetSize > 0 ||
      85           0 :                      FetchOffset <= 0) &&
      86           0 :                     ((SQLULEN) stmt->startRow < stmt->rowcount ||
      87             :                      FetchOffset >= 0)) {
      88           0 :                         if ((stmt->startRow == 0 && stmt->rowSetSize == 0 &&
      89           0 :                              FetchOffset <= 0) ||
      90           0 :                             (stmt->startRow == 0 && stmt->rowSetSize > 0 &&
      91           0 :                              FetchOffset < 0) ||
      92           0 :                             (stmt->startRow > 0 &&
      93           0 :                              stmt->startRow + FetchOffset < 1 &&
      94           0 :                              (FetchOffset > (SQLLEN) RowSetSize ||
      95           0 :                               -FetchOffset > (SQLLEN) RowSetSize))) {
      96             :                                 /* before start */
      97           0 :                                 stmt->startRow = 0;
      98           0 :                                 stmt->rowSetSize = 0;
      99           0 :                                 stmt->State = FETCHED;
     100           0 :                                 return SQL_NO_DATA;
     101             :                         }
     102           0 :                         if (stmt->startRow > 0 &&
     103           0 :                             stmt->startRow + FetchOffset < 1 &&
     104           0 :                             FetchOffset <= (SQLLEN) RowSetSize &&
     105           0 :                             -FetchOffset <= (SQLLEN) RowSetSize) {
     106             :                                 /* Attempt to fetch before the result
     107             :                                  * set returned the first rowset */
     108           0 :                                 addStmtError(stmt, "01S06", NULL, 0);
     109           0 :                                 stmt->startRow = 0;
     110           0 :                                 break;
     111             :                         }
     112           0 :                         if (stmt->startRow + FetchOffset >= 0 &&
     113           0 :                             stmt->startRow + FetchOffset < (SQLLEN) stmt->rowcount) {
     114           0 :                                 stmt->startRow += FetchOffset;
     115           0 :                                 break;
     116             :                         }
     117           0 :                         if (stmt->startRow + FetchOffset >= (SQLLEN) stmt->rowcount ||
     118           0 :                             (stmt->startRow >= (SQLLEN) stmt->rowcount &&
     119             :                              FetchOffset >= 0)) {
     120             :                                 /* after end */
     121           0 :                                 stmt->startRow = stmt->rowcount;
     122           0 :                                 stmt->rowSetSize = 0;
     123           0 :                                 stmt->State = FETCHED;
     124           0 :                                 return SQL_NO_DATA;
     125             :                         }
     126             :                         /* all bases should have been covered above */
     127           0 :                         assert(0);
     128             :                 }
     129             :                 /* fall through */
     130             :         case SQL_FETCH_ABSOLUTE:
     131           0 :                 if (FetchOffset < 0) {
     132           0 :                         if ((unsigned int) -FetchOffset <= stmt->rowcount) {
     133           0 :                                 stmt->startRow = stmt->rowcount + FetchOffset;
     134           0 :                                 break;
     135             :                         }
     136           0 :                         stmt->startRow = 0;
     137           0 :                         if ((unsigned int) -FetchOffset > RowSetSize) {
     138             :                                 /* before start */
     139           0 :                                 stmt->State = FETCHED;
     140           0 :                                 stmt->rowSetSize = 0;
     141           0 :                                 return SQL_NO_DATA;
     142             :                         }
     143             :                         /* Attempt to fetch before the result set
     144             :                            returned the first rowset */
     145           0 :                         addStmtError(stmt, "01S06", NULL, 0);
     146           0 :                         break;
     147             :                 }
     148           0 :                 if (FetchOffset == 0) {
     149             :                         /* before start */
     150           0 :                         stmt->startRow = 0;
     151           0 :                         stmt->rowSetSize = 0;
     152           0 :                         stmt->State = FETCHED;
     153           0 :                         return SQL_NO_DATA;
     154             :                 }
     155           0 :                 if ((SQLULEN) FetchOffset > stmt->rowcount) {
     156             :                         /* after end */
     157           0 :                         stmt->startRow = stmt->rowcount;
     158           0 :                         stmt->rowSetSize = 0;
     159           0 :                         stmt->State = FETCHED;
     160           0 :                         return SQL_NO_DATA;
     161             :                 }
     162           0 :                 stmt->startRow = FetchOffset - 1;
     163           0 :                 break;
     164           0 :         case SQL_FETCH_BOOKMARK:
     165             :                 /* Optional feature not implemented */
     166           0 :                 addStmtError(stmt, "HYC00", NULL, 0);
     167           0 :                 return SQL_ERROR;
     168           0 :         default:
     169             :                 /* Fetch type out of range */
     170           0 :                 addStmtError(stmt, "HY106", NULL, 0);
     171           0 :                 return SQL_ERROR;
     172             :         }
     173             : 
     174        1001 :         return MNDBFetch(stmt, RowStatusArray);
     175             : }
     176             : 
     177             : SQLRETURN SQL_API
     178             : SQLFetchScroll(SQLHSTMT StatementHandle,
     179             :                SQLSMALLINT FetchOrientation,
     180             :                SQLLEN FetchOffset)
     181             : {
     182        1001 :         ODBCStmt *stmt = (ODBCStmt *) StatementHandle;
     183             : 
     184             : #ifdef ODBCDEBUG
     185        1001 :         ODBCLOG("SQLFetchScroll %p %s " LENFMT "\n",
     186             :                 StatementHandle,
     187             :                 translateFetchOrientation(FetchOrientation),
     188             :                 LENCAST FetchOffset);
     189             : #endif
     190             : 
     191        1001 :         if (!isValidStmt(stmt))
     192             :                  return SQL_INVALID_HANDLE;
     193             : 
     194        1001 :         clearStmtErrors(stmt);
     195             : 
     196             :         /* check statement cursor state, query should be executed */
     197        1001 :         if (stmt->State < EXECUTED0 || stmt->State == EXTENDEDFETCHED) {
     198             :                 /* Function sequence error */
     199           0 :                 addStmtError(stmt, "HY010", NULL, 0);
     200           0 :                 return SQL_ERROR;
     201             :         }
     202        1001 :         if (stmt->State == EXECUTED0) {
     203             :                 /* Invalid cursor state */
     204           0 :                 addStmtError(stmt, "24000", NULL, 0);
     205           0 :                 return SQL_ERROR;
     206             :         }
     207             : 
     208        1001 :         return MNDBFetchScroll(stmt, FetchOrientation, FetchOffset,
     209        1001 :                                stmt->ImplRowDescr->sql_desc_array_status_ptr);
     210             : }