GCIPage.cpp
上传用户:romrleung
上传日期:2022-05-23
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文件大小:4k
- /* Copyright (C) 2003 MySQL AB
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
- This program 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 General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
- #include "GCIPage.hpp"
- #include "assert.h"
- #include <new>
- GCIPage::GCIPage(Uint32 gci)
- {
- m_first = NULL;
- m_last = NULL;
- m_gci = gci;
- m_full = false;
- m_currentPagePos=m_page;
- m_usedBytes = 0;
- }
- /*****************************************************************************
- * Insert
- *****************************************************************************/
- /**
- * Store a new log record on this page.
- * @return True if success, false otherwise
- */
- bool
- GCIPage::insertLogRecord(Uint32 tableId, Uint32 operation,
- class LinearSectionPtr ptr[3])
- {
- /**
- * Calculate size of new logrecord in bytes
- */
- assert(m_page!=NULL);
- Uint32 size = 4*ptr[0].sz + 4*ptr[1].sz + sizeof(LogRecord);
- if(!((m_currentPagePos + size ) < (m_page + m_pageBSize))) {
- m_full = true;
- return false; // No free space. GCIBuffer must allocate a new page
- }
- LogRecord * lr = new(m_currentPagePos) LogRecord();
- if (lr==0) REPABORT("Could not allocate new log record");
-
- lr->recordType = Record::LOG;
- lr->recordLen = size;
- lr->operation = operation;
- lr->tableId = tableId;
- lr->attributeHeaderWSize = ptr[0].sz;
- lr->attributeDataWSize = ptr[1].sz;
-
- m_currentPagePos += sizeof(LogRecord);
-
- lr->attributeHeader = (Uint32*)m_currentPagePos;
- memcpy(lr->attributeHeader, ptr[0].p, lr->attributeHeaderWSize * 4);
-
- m_currentPagePos += lr->attributeHeaderWSize * 4;
-
- lr->attributeData = (Uint32*)m_currentPagePos;
- memcpy(lr->attributeData, ptr[1].p, lr->attributeDataWSize * 4);
-
- m_currentPagePos += lr->attributeDataWSize * 4;
- m_usedBytes+=size;
- return true;
- }
- /**
- * Store a new log record on this page.
- * @return True if sucessful, false otherwise.
- */
- bool
- GCIPage::insertMetaRecord(Uint32 tableId, class LinearSectionPtr ptr[3])
- {
- /**
- * Calculate size of new logrecord in bytes
- */
- Uint32 size = 4*ptr[0].sz + sizeof(MetaRecord);
-
- if(!((m_currentPagePos + size ) < (m_page + m_pageBSize))) {
- m_full = true;
- return false; // No free space. GCIBuffer must allocate a new page
- }
- MetaRecord * mr = new(m_currentPagePos) MetaRecord();
- if (mr==0) REPABORT("Could not allocate new meta record");
- // mr->operation = operation;
- mr->recordType = Record::META;
- mr->recordLen = size;
- mr->tableId = tableId;
- mr->dataLen = ptr[0].sz;
-
- m_currentPagePos += sizeof(MetaRecord);
-
- mr->data = (Uint32*)m_currentPagePos;
- memcpy(mr->data, ptr[0].p, mr->dataLen * 4);
-
- m_currentPagePos += mr->dataLen * 4;
- m_usedBytes+=size;
- return true;
- }
- /**
- * copy function
- */
- void
- GCIPage::copyDataToPage(char * dataPtr, Uint32 dataBLen)
- {
- assert (dataBLen < m_pageBSize);
- memcpy(m_page, dataPtr, dataBLen);
- m_currentPagePos=m_page + dataBLen;
- m_usedBytes = dataBLen;
- m_full = true;
- m_first = (Record * )m_page;
- dataPtr = 0;
- }
- /*****************************************************************************
- * Iterator
- *****************************************************************************/
- GCIPage::iterator::iterator(const GCIPage* page)
- {
- m_gciPage = page;
- m_data = m_gciPage->m_page;
- m_currentRecord = (Record*)m_data;
- }
- Record *
- GCIPage::iterator::first()
- {
- return m_currentRecord;
- }
- Record *
- GCIPage::iterator::next()
- {
- m_currentRecord = (Record*)
- ((char*)(m_currentRecord)+ m_currentRecord->recordLen);
- if((char*)m_currentRecord < (char*)(m_data + m_gciPage->m_usedBytes))
- return m_currentRecord;
- else {
- return 0;
- }
- }
- bool
- GCIPage::iterator::exists()
- {
- return ((char*)m_currentRecord < (m_data + m_gciPage->m_usedBytes));
- }