FSIndexInput.h

00001 //
00002 // Copyright(C) 2005--2006 Institute of Computing Tech, Chinese Academy of Sciences. 
00003 // All rights reserved.
00004 // This file is part of FirteX (www.firtex.org)
00005 //
00006 // Use of the FirteX is subject to the terms of the software license set forth in 
00007 // the LICENSE file included with this software, and also available at
00008 // http://www.firtex.org/license.html
00009 //
00010 // Author       : 郭瑞杰(GuoRuijie)
00011 // Email        : ruijieguo@software.ict.ac.cn,ruijieguo@gmail.com
00012 // Created      : 2005/11/9
00013 //
00014 #ifndef __FILECACHEREADER_H
00015 #define __FILECACHEREADER_H
00016 
00017 #if _MSC_VER > 1000
00018 #pragma once
00019 #endif // _MSC_VER > 1000
00020 
00021 
00022 #include <fstream>
00023 #include <string>
00024 #include "IndexInput.h"
00025 #include "utility/Config.h"
00026 
00027 using namespace std;
00028 
00029 namespace firtex
00030 {
00031         namespace store
00032         {
00033                 class CFSIndexInput : public CIndexInput
00034                 {                               
00035                 public:
00036                         CFSIndexInput(const tchar* filename)
00037                         {                               
00038                                 m_fileHandle = ::fileOpen(filename, O_BINARY | O_RDONLY | O_RANDOM, _S_IREAD );
00039                         
00040                                 if (m_fileHandle < 0)
00041                                 {
00042                                         int err = errno;
00043                                         tstring sFileName = filename;
00044                                         if ( err == ENOENT )
00045                                                 FIRTEX_THROW2(FILEIO_ERROR,"File does not exist: " + sFileName);
00046                                         else if ( err == EACCES )
00047                                                 FIRTEX_THROW2(FILEIO_ERROR,"File Access denied: " + sFileName);
00048                                         else if ( err == EMFILE )
00049                                                 FIRTEX_THROW2(FILEIO_ERROR,"Too many open files: " + sFileName);
00050                                 }                               
00051                                 m_length = fileSize(m_fileHandle);
00052                                 m_filename = filename;
00053                         }
00054                         CFSIndexInput(const tchar* filename,char* buffer,size_t buffsize):CIndexInput(buffer,buffsize)
00055                         {
00056                                 m_fileHandle = ::fileOpen(filename, O_BINARY | O_RDONLY | O_RANDOM, _S_IREAD );
00057 
00058                                 if (m_fileHandle < 0)
00059                                 {
00060                                         int err = errno;
00061                                         tstring sFileName = filename;
00062                                         if ( err == ENOENT )
00063                                                 FIRTEX_THROW2(FILEIO_ERROR,"File does not exist: " + sFileName);
00064                                         else if ( err == EACCES )
00065                                                 FIRTEX_THROW2(FILEIO_ERROR,"File Access denied: " + sFileName);
00066                                         else if ( err == EMFILE )
00067                                                 FIRTEX_THROW2(FILEIO_ERROR,"Too many open files: " + sFileName);
00068                                 }                               
00069                                 m_length = fileSize(m_fileHandle);
00070                                 m_filename = filename;
00071                         }
00072                         CFSIndexInput(const tchar* filename,size_t buffsize):CIndexInput(buffsize)
00073                         {
00074                                 m_fileHandle = ::fileOpen(filename, O_BINARY | O_RDONLY | O_RANDOM, _S_IREAD );
00075 
00076                                 if (m_fileHandle < 0)
00077                                 {
00078                                         int err = errno;
00079                                         tstring sFileName = filename;
00080                                         if ( err == ENOENT )
00081                                                 FIRTEX_THROW2(FILEIO_ERROR,"File does not exist: " + sFileName);
00082                                         else if ( err == EACCES )
00083                                                 FIRTEX_THROW2(FILEIO_ERROR,"File Access denied: " + sFileName);
00084                                         else if ( err == EMFILE )
00085                                                 FIRTEX_THROW2(FILEIO_ERROR,"Too many open files: " + sFileName);
00086                                 }                               
00087                                 m_length = fileSize(m_fileHandle);
00088                                 m_filename = filename;
00089                         }
00090 
00091                         virtual ~CFSIndexInput()
00092                         {
00093                                 close(); 
00094                         }
00095                 public:
00096                         void  readInternal(char* b, size_t offset, size_t len)
00097                         {
00098                                 int64_t position = getFilePointer();
00099                                 if (position != fileTell(m_fileHandle))
00100                                 {
00101                                         if(fileSeek(m_fileHandle,position,SEEK_SET) != position)
00102                                                 FIRTEX_THROW2(FILEIO_ERROR,"CFSIndexInput::readInternal():file IO seek error: " + m_filename);
00103                                 }                               
00104                                 size_t ret = ::fileRead(m_fileHandle,b+offset,(unsigned int)len);
00105                                 if(ret == 0)
00106                                         FIRTEX_THROW2(FILEIO_ERROR,"CFSIndexInput::readInternal():read past EOF:" + m_filename);
00107                                 else if (ret == -1)
00108                                 {
00109                                         int err = errno;
00110                                         cout << err;
00111                                         FIRTEX_THROW2(FILEIO_ERROR,"CFSIndexInput::readInternal():file IO read error:" + m_filename);
00112                                 }
00113                         }
00114 
00115                         void  close()
00116                         {
00117                                 if(m_fileHandle >= 0)
00118                                 {
00119                                         ::fileClose(m_fileHandle);                                      
00120                                         m_fileHandle = -1;
00121                                 }                               
00122                         }                       
00123 
00124                         
00125                         CIndexInput*    clone(char* buffer,size_t buffsize)
00126                         {                               
00127                                 CFSIndexInput* pClone = new CFSIndexInput(m_filename.c_str(),buffer,buffsize);
00128                                 return pClone;
00129                         }
00130                                                         
00131                         CIndexInput*    clone()
00132                         {
00133                                 CFSIndexInput* pClone = new CFSIndexInput(m_filename.c_str(),m_bufferSize);
00134                                 return pClone;
00135                         }
00136                 protected:
00137                         void  seekInternal(int64_t position)
00138                         {
00139                                 if(fileSeek(m_fileHandle,position,SEEK_SET) != position)
00140                                         FIRTEX_THROW2(FILEIO_ERROR,"CFSIndexInput::seekInternal():file IO seek error: " + m_filename);
00141                         }               
00142                 protected:                      
00143                         int                             m_fileHandle;
00144                         tstring                 m_filename;
00145                 };
00146         }
00147 }
00148 
00149 
00150 #endif