LA library: auxstorage.h Source File

00001 /*
00002     LA: linear algebra C++ interface library
00003     Copyright (C) 2008 Jiri Pittner <jiri.pittner@jh-inst.cas.cz> or <jiri@pittnerovi.com>
00004 
00005     This program is free software: you can redistribute it and/or modify
00006     it under the terms of the GNU General Public License as published by
00007     the Free Software Foundation, either version 3 of the License, or
00008     (at your option) any later version.
00009 
00010     This program is distributed in the hope that it will be useful,
00011     but WITHOUT ANY WARRANTY; without even the implied warranty of
00012     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013     GNU General Public License for more details.
00014 
00015     You should have received a copy of the GNU General Public License
00016     along with this program.  If not, see <http://www.gnu.org/licenses/>.
00017 */
00018 #ifndef _AUXSTORAGE_H_
00019 #define _AUXSTORAGE_H_
00020 
00021 #include "vec.h"
00022 #include "mat.h"
00023 #include "smat.h"
00024 
00025 #include <stdlib.h>
00026 #include <sys/types.h>
00027 #include <sys/stat.h>
00028 #include <fcntl.h>
00029 #include <unistd.h>
00030 
00031 namespace LA {
00032 
00033 //CAUTION:
00034 //it will not work if T is itself a class with dynamically allocated components
00035 //it cannot be implemented for SparseMat, which lacks fixed record length
00036 //for more complex I/O use put() and get() methods of the individual classes
00037 
00038 
00039 
00040 template<typename T>
00041 class AuxStorage
00042         {
00043         char filename[32];
00044         int fd;
00045         bool deleteme;
00046         size_t recl;
00047 public:
00048         AuxStorage(void);
00049         AuxStorage(const char *name);
00050         ~AuxStorage(void) {close(fd); if(deleteme) unlink(filename);};
00051         void get(NRVec<T> &x, const int pos) const;
00052         void put(const NRVec<T> &x, const int pos);
00053         void get(NRMat<T> &x, const int pos) const;
00054         void put(const NRMat<T> &x, const int pos);
00055         void get(NRSMat<T> &x, const int pos) const;
00056         void put(const NRSMat<T> &x, const int pos);
00057         };
00058 
00059 template<typename T>
00060 AuxStorage<T>::AuxStorage(void)
00061 {
00062 //mkstemp probable does not support O_LARGEFILE?!
00063 strcpy(filename,"AUX_XXXXXX"); 
00064 mktemp(filename); 
00065 unlink(filename);
00066 fd=open(filename,O_CREAT|O_LARGEFILE|O_RDWR,0777);
00067 if(fd<0) {perror(""); laerror("open failed in AuxStorage");}
00068 recl=0;
00069 deleteme=1;
00070 }
00071 
00072 template<typename T>
00073 AuxStorage<T>::AuxStorage(const char *name)
00074 {
00075 strcpy(filename,name);
00076 unlink(filename);
00077 fd=open(filename,O_CREAT|O_LARGEFILE|O_RDWR,0777);
00078 if(fd<0) {perror(""); laerror("open failed in AuxStorage");}
00079 recl=0;
00080 deleteme=0;
00081 }
00082 
00083 
00084 //vectors
00085 template<typename T>
00086 void AuxStorage<T>::get(NRVec<T> &x, const int pos) const
00087 {
00088 if(recl==0) laerror("get from an empty file in AuxStorage");
00089 if((off64_t)-1 == lseek64(fd,pos*((off64_t)recl),SEEK_SET)) {perror(""); laerror("seek failed in AuxStorage");}
00090 x.copyonwrite();
00091 if((ssize_t)recl!=read(fd,&x[0],recl)) {perror(""); laerror("read failed in AuxStorage");}
00092 }
00093 
00094 template<typename T>
00095 void AuxStorage<T>::put(const NRVec<T> &x, const int pos)
00096 {
00097 if(recl) {if(recl!=x.size()*sizeof(T)) laerror("attempt to write objects of different size to one AuxStorage");}
00098 else recl=x.size()*sizeof(T);
00099 if((off64_t)-1 == lseek64(fd,pos*((off64_t)recl),SEEK_SET)) {perror(""); laerror("seek failed in AuxStorage");}
00100 if(0>write(fd,&x[0],recl)) {perror(""); laerror("write failed in AuxStorage");}
00101 }
00102 
00103 //matrices
00104 template<typename T>
00105 void AuxStorage<T>::get(NRMat<T> &x, const int pos) const
00106 {
00107 if(recl==0) laerror("get from an empty file in AuxStorage");
00108 if((off64_t)-1 == lseek64(fd,pos*((off64_t)recl),SEEK_SET)) {perror(""); laerror("seek failed in AuxStorage");}
00109 x.copyonwrite();
00110 if((ssize_t)recl!=read(fd,&x(0,0),recl)) {perror(""); laerror("read failed in AuxStorage");}
00111 }
00112 
00113 template<typename T>
00114 void AuxStorage<T>::put(const NRMat<T> &x, const int pos)
00115 {
00116 if(recl) {if(recl!=x.nrows()*x.ncols()*sizeof(T)) laerror("attempt to write objects of different size to one AuxStorage");}
00117 else recl=x.nrows()*x.ncols()*sizeof(T);
00118 if((off64_t)-1 == lseek64(fd,pos*((off64_t)recl),SEEK_SET)) {perror(""); laerror("seek failed in AuxStorage");}
00119 if(0>write(fd,&x(0,0),recl)) {perror(""); laerror("write failed in AuxStorage");}
00120 }
00121 
00122 //packed symmetric matrices
00123 template<typename T>
00124 void AuxStorage<T>::get(NRSMat<T> &x, const int pos) const
00125 {
00126 if(recl==0) laerror("get from an empty file in AuxStorage");
00127 if((off64_t)-1 == lseek64(fd,pos*((off64_t)recl),SEEK_SET)) {perror(""); laerror("seek failed in AuxStorage");}
00128 x.copyonwrite();
00129 if((ssize_t)recl!=read(fd,&x(0,0),recl)) {perror(""); laerror("read failed in AuxStorage");}
00130 }
00131 
00132 template<typename T>
00133 void AuxStorage<T>::put(const NRSMat<T> &x, const int pos)
00134 {
00135 if(recl) {if(recl!=x.nrows()*(x.nrows()+1)/2*sizeof(T)) laerror("attempt to write objects of different size to one AuxStorage");}
00136 else recl=x.nrows()*(x.nrows()+1)/2*sizeof(T);
00137 if((off64_t)-1 == lseek64(fd,pos*((off64_t)recl),SEEK_SET)) {perror(""); laerror("seek failed in AuxStorage");}
00138 if(0>write(fd,&x(0,0),recl)) {perror(""); laerror("write failed in AuxStorage");}
00139 }
00140 
00141 
00142 }//namespace
00143 
00144 #endif