src/io/basic_ifstrstream.hpp

 /*
 * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
 *
 * The University of Notre Dame grants you ("Licensee") a
 * non-exclusive, royalty free, license to use, modify and
 * redistribute this software in source and binary code form, provided
 * that the following conditions are met:
 *
 * 1. Acknowledgement of the program authors must be made in any
 *    publication of scientific results based in part on use of the
 *    program.  An acceptable form of acknowledgement is citation of
 *    the article in which the program was described (Matthew
 *    A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher
 *    J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented
 *    Parallel Simulation Engine for Molecular Dynamics,"
 *    J. Comput. Chem. 26, pp. 252-271 (2005))
 *
 * 2. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 3. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the
 *    distribution.
 *
 * This software is provided "AS IS," without a warranty of any
 * kind. All express or implied conditions, representations and
 * warranties, including any implied warranty of merchantability,
 * fitness for a particular purpose or non-infringement, are hereby
 * excluded.  The University of Notre Dame and its licensors shall not
 * be liable for any damages suffered by licensee as a result of
 * using, modifying or distributing the software or its
 * derivatives. In no event will the University of Notre Dame or its
 * licensors be liable for any lost revenue, profit or data, or for
 * direct, indirect, special, consequential, incidental or punitive
 * damages, however caused and regardless of the theory of liability,
 * arising out of the use of or inability to use software, even if the
 * University of Notre Dame has been advised of the possibility of
 * such damages.
 */
 
/**
 * @file basic_ifstrstream.hpp
 * @author Teng Lin
 * @date 10/14/2004
 * @version 1.0
 */

#ifndef IO_IFSTRSTREAM_HPP
#define IO_IFSTRSTREAM_HPP

#include <cassert>
#include <cstring>
#include <fstream>
#include <sstream>

#ifdef IS_MPI
#include <mpi.h>
#endif

namespace oopse {

/**
 * @class basic_ifstrstream basic_ifstrstream.hpp "io/basic_ifstrstream.hpp"
 * @brief basic_ifstrstream class provides a stream interface to read data from files.
 * <p>In single mode, it falls back to ifstream. Don't need to read the whole file into memory.
 * In parallel mode, the master node will read the whole file and brocast it to other slave nodes.
 * After brocasting, every node will fall back to stringstream.</p>
 *
 * @code
 *       const int MAXLEN = 1024;
 *       char buffer[MAXLEN];
 *       ifstrstream in;
 *       in.open("Shapes.frc");
 *       if (in.is_open()) {
 *           in.getline(buffer, MAXLEN);
 *       }
 *       in.close();
 * @endcode
 */
template <class _CharT, class _Traits,  class _Alloc>
class basic_ifstrstream : public std::basic_istream<_CharT, _Traits> {
    public:
        //traits
        typedef _CharT                     char_type;
        typedef typename _Traits::int_type int_type;
        typedef typename _Traits::pos_type pos_type;
        typedef typename _Traits::off_type off_type;
        typedef _Traits                    traits_type;

        typedef std::basic_ios<_CharT, _Traits>                _Basic_ios;
        typedef std::basic_istream<_CharT, _Traits>            _Base;

#ifdef IS_MPI
         typedef std::basic_stringbuf<_CharT, _Traits, _Alloc>  _Buf;        
#else
        typedef std::basic_filebuf<_CharT, _Traits>            _Buf;
#endif

        static  const int FileNotExists = -1;
        static const int FileIOError = -2;
        
    public:
        
        /**  Constructs an object of class ifstream.  */
        basic_ifstrstream()
            : std::basic_ios<_CharT, _Traits>(),  std::basic_istream<_CharT, _Traits>(0),
              internalBuf_(NULL), isRead(false)  {

#ifdef IS_MPI         
            //in parallel mode, fall back to istringstream
            std::basic_stringbuf<_CharT, _Traits, _Alloc>* stringBuffer = new  std::basic_stringbuf<_CharT, _Traits, _Alloc>();
            internalBuf_ =  stringBuffer;
#else
            //in single version, fall back to ifstream
            std::basic_filebuf<_CharT, _Traits>* fileBuffer = new  std::basic_filebuf<_CharT, _Traits>();
            internalBuf_ =  fileBuffer;
#endif            

            this->init(internalBuf_);
            isRead = false;
        }
        
        /**
         * Explicit constructor
         * @filename String containing the name of the file to be opened
         * @mode Flags describing the requested i/o mode for the file, default value is ios_base::in      
         * @checkFilename Flags indicating checking the file name in parallel
         */
        explicit basic_ifstrstream(const char* filename, std::ios_base::openmode mode = std::ios_base::in, bool checkFilename = false)
            : std::basic_ios<_CharT, _Traits>(),  std::basic_istream<_CharT, _Traits>(0),
              internalBuf_(NULL), isRead(false) {

           isRead =  internalOpen(filename,  mode | std::ios_base::in, checkFilename);
         }

        /**
         * virtual destructor will close the file(in single mode) and clear the stream buffer
         */
        ~basic_ifstrstream(){
            close();
            delete internalBuf_;
            internalBuf_ = NULL;
        }

        /**
         * Opens a file and associats a buffer with the specified file to perform the i/o operations 
         * (single mode). Master reads a file and brocasts its content to the other slave nodes. After
         * brocasting, every nodes fall back to stringstream (parallel mode).
         * @filename String containing the name of the file to be opened
         * @mode Flags describing the requested i/o mode for the file
         * @checkFilename Flags indicating checking the file name in parallel
         */
        void open(const char* filename, std::ios_base::openmode mode = std::ios_base::in, bool checkFilename = false){

            if (!isRead ) {
                isRead = internalOpen(filename, mode, checkFilename);
            }
        }

        /**
         * Tests if the stream is currently associated with a valid  buffer.
         * @return true if a file has successfully been opened (single mode) or the whole file is read 
         * and spreaded among all of the processors (parallel mode),  otherwise false is returned
         */
        bool is_open ( ) {
#ifdef IS_MPI            
            return isRead; 
#else
            //single version fall back to ifstream
            return this->rdbuf()->is_open();
#endif
        }

        /**
         * In single mode, closes a file. The stream's file buffer is released from its association with
         * the currently open file. In parallel mode, clean the 
         */
        void close() {
#ifndef IS_MPI            
            //single version fall back to ifstream
            if (!this->rdbuf()->close())
                this->setstate(std::ios_base::failbit);
#endif             

            isRead = false;
        }
        
        /**
         * Gets the stream buffer object associated with the stream
         * @return   A pointer to the  stream buffe object(filebuf in single mode, stringbuf in 
         * parallel mode) associated with the stream.
         */
        _Buf* rdbuf() const{
            return static_cast<_Buf*>(internalBuf_); 
        }

    private:

        /**
         * Internal function used to open the file
         * @return true if succesfully opens a file (single mode) or gets the file content (parallel mode)
         * otherwise return false
         * @filename String containing the name of the file to be opened
         * @mode Flags describing the requested i/o mode for the file
         * @todo use try - catch syntax to make the program more readable
         */
        bool internalOpen(const char* filename, std::ios_base::openmode mode, bool checkFilename){

#ifdef IS_MPI         
            int commStatus;
            long fileSize;
            char* fbuf;
            int filenameLen;
            int diffFilename;
            int error;
            int myRank;
            int masterNode;

            commStatus = MPI_Comm_rank(MPI_COMM_WORLD, &myRank);
            masterNode = 0;
            
            if (myRank == masterNode) {

                if (checkFilename) {

                    //check the filename is the same
                    filenameLen = strlen(filename);
                    commStatus = MPI_Bcast(&filenameLen, 1, MPI_INT, masterNode, MPI_COMM_WORLD);     
                    commStatus = MPI_Bcast((void*)filename, filenameLen, MPI_CHAR, masterNode, MPI_COMM_WORLD);     

                    diffFilename = 0;
                    commStatus = MPI_Allreduce(&diffFilename, &error, 1,  MPI_INT, MPI_SUM,  MPI_COMM_WORLD);             

                    //if file names are different just return false
                    if (error > 0)
                        return false;   
                }
                
                std::ifstream fin(filename, mode);
                std::basic_stringbuf<_CharT, _Traits, _Alloc>* sbuf;

                if (fin.is_open()) {
                    
                    fin.seekg(0, std::ios::end); 
                    fileSize = fin.tellg(); 
                    fin.seekg(0, std::ios::beg);
                    
                    // '\0' need one more char
                    fbuf = new char[fileSize+1];
                    
                    assert(fbuf != 0);

                    fin.read(fbuf, fileSize);

                    if (fin.fail())
                        fileSize = FileIOError;
                    
                    //brocasting the file size
                    commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);                   

                    if (fileSize < 0) {
                        fin.close();                    
                        delete fbuf;
                        
                        return false;
                    }
                    
                    // make a c-style  std::string and brocasting it
                    fbuf[fileSize] = '\0';
                    commStatus = MPI_Bcast(fbuf, fileSize + 1, MPI_CHAR, masterNode, MPI_COMM_WORLD); 

                    //it is safe to delete null pointer
                    delete internalBuf_;

                    //initilaize istream
                    internalBuf_  = new std::basic_stringbuf<_CharT, _Traits, _Alloc>(fbuf, mode);
                    assert(internalBuf_);
                    this->init(internalBuf_);

                    //close the file and delete the buffer
                    fin.close();                    
                    delete fbuf;
                }else{
                    fileSize = FileNotExists;
                    commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);   
                    return false;
                }
               
             } else{ //slave nodes

                    //check file name
                    if (checkFilename) {
                        commStatus = MPI_Bcast(&filenameLen, 1, MPI_INT, masterNode, MPI_COMM_WORLD);     

                        char * masterFilename = new char[filenameLen];
                        commStatus = MPI_Bcast(masterFilename, filenameLen, MPI_CHAR, masterNode, MPI_COMM_WORLD);     
        
                        if( strcmp(masterFilename, filename) == 0)
                            diffFilename = 0;
                        else
                            diffFilename = 1;

                        delete masterFilename;
                        
                        commStatus = MPI_Allreduce(&diffFilename, &error, 1,  MPI_INT,  MPI_SUM, MPI_COMM_WORLD);    

                        if (error > 0)
                            return false;                        
                    }
                    //get file size
                    commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);   

                    if (fileSize >= 0 ) {
                        fbuf = new char[fileSize+1];
                        assert(fbuf);

                        //receive file content
                        commStatus = MPI_Bcast(fbuf, fileSize + 1, MPI_CHAR, masterNode, MPI_COMM_WORLD); 

                        //it is safe to delete null pointer
                        delete internalBuf_;

                        //initilaize istream                        
                        internalBuf_  = new std::basic_stringbuf<_CharT, _Traits, _Alloc>(fbuf, mode);
                        assert(internalBuf_);
                        this->init(internalBuf_);

                        delete fbuf;

                    } else if (fileSize == FileNotExists ) {
                        return false;

                    } else if (fileSize == FileIOError ) {
                        return false;
                    }
             }

#else
            //in single version, fall back to ifstream
            std::basic_filebuf<_CharT, _Traits>* fileBuffer = new  std::basic_filebuf<_CharT, _Traits>();

            //it is safe to delete null pointer
            delete internalBuf_; 
            internalBuf_ =  fileBuffer;

            this->init(internalBuf_);
            if (!fileBuffer->open(filename, mode)) {
                this->setstate(std::ios_base::failbit);
                return false;
            }    

#endif

            return true;
        }
        
        std::basic_streambuf<_CharT, _Traits>*  internalBuf_; /** internal stream buffer */        
        bool isRead;                                                                    /** file opened flag */
};

typedef basic_ifstrstream<char, std::char_traits<char>, std::allocator<char> > ifstrstream;
}//namespace oopse
#endif //IO_IFSTRSTREAM_HPP
Revision:	1930
Committed:	Wed Jan 12 22:41:40 2005 UTC (20 years, 9 months ago) by gezelter
File size:	14220 byte(s)
Log Message:	merging new_design branch into OOPSE-2.0
#	User	Rev	Content
1	gezelter	1930	/*
2			* Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
3	tim	1570	*
4	gezelter	1930	* The University of Notre Dame grants you ("Licensee") a
5			* non-exclusive, royalty free, license to use, modify and
6			* redistribute this software in source and binary code form, provided
7			* that the following conditions are met:
8			*
9			* 1. Acknowledgement of the program authors must be made in any
10			* publication of scientific results based in part on use of the
11			* program. An acceptable form of acknowledgement is citation of
12			* the article in which the program was described (Matthew
13			* A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher
14			* J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented
15			* Parallel Simulation Engine for Molecular Dynamics,"
16			* J. Comput. Chem. 26, pp. 252-271 (2005))
17			*
18			* 2. Redistributions of source code must retain the above copyright
19			* notice, this list of conditions and the following disclaimer.
20			*
21			* 3. Redistributions in binary form must reproduce the above copyright
22			* notice, this list of conditions and the following disclaimer in the
23			* documentation and/or other materials provided with the
24			* distribution.
25			*
26			* This software is provided "AS IS," without a warranty of any
27			* kind. All express or implied conditions, representations and
28			* warranties, including any implied warranty of merchantability,
29			* fitness for a particular purpose or non-infringement, are hereby
30			* excluded. The University of Notre Dame and its licensors shall not
31			* be liable for any damages suffered by licensee as a result of
32			* using, modifying or distributing the software or its
33			* derivatives. In no event will the University of Notre Dame or its
34			* licensors be liable for any lost revenue, profit or data, or for
35			* direct, indirect, special, consequential, incidental or punitive
36			* damages, however caused and regardless of the theory of liability,
37			* arising out of the use of or inability to use software, even if the
38			* University of Notre Dame has been advised of the possibility of
39			* such damages.
40	tim	1570	*/
41	gezelter	1930
42	tim	1570	/**
43			* @file basic_ifstrstream.hpp
44			* @author Teng Lin
45			* @date 10/14/2004
46			* @version 1.0
47			*/
48
49			#ifndef IO_IFSTRSTREAM_HPP
50			#define IO_IFSTRSTREAM_HPP
51
52	tim	1583	#include <cassert>
53	tim	1572	#include <cstring>
54	tim	1570	#include <fstream>
55			#include <sstream>
56
57	tim	1572	#ifdef IS_MPI
58	tim	1577	#include <mpi.h>
59	tim	1572	#endif
60
61	tim	1570	namespace oopse {
62	gezelter	1930
63	tim	1570	/**
64			* @class basic_ifstrstream basic_ifstrstream.hpp "io/basic_ifstrstream.hpp"
65	gezelter	1930	* @brief basic_ifstrstream class provides a stream interface to read data from files.
66	tim	1570	* <p>In single mode, it falls back to ifstream. Don't need to read the whole file into memory.
67			* In parallel mode, the master node will read the whole file and brocast it to other slave nodes.
68			* After brocasting, every node will fall back to stringstream.</p>
69			*
70			* @code
71			* const int MAXLEN = 1024;
72			* char buffer[MAXLEN];
73			* ifstrstream in;
74			* in.open("Shapes.frc");
75	tim	1572	* if (in.is_open()) {
76	tim	1570	* in.getline(buffer, MAXLEN);
77			* }
78			* in.close();
79			* @endcode
80			*/
81			template <class _CharT, class _Traits, class _Alloc>
82	gezelter	1930	class basic_ifstrstream : public std::basic_istream<_CharT, _Traits> {
83	tim	1570	public:
84			//traits
85			typedef _CharT char_type;
86			typedef typename _Traits::int_type int_type;
87			typedef typename _Traits::pos_type pos_type;
88			typedef typename _Traits::off_type off_type;
89			typedef _Traits traits_type;
90
91	gezelter	1930	typedef std::basic_ios<_CharT, _Traits> _Basic_ios;
92			typedef std::basic_istream<_CharT, _Traits> _Base;
93	tim	1570
94			#ifdef IS_MPI
95	gezelter	1930	typedef std::basic_stringbuf<_CharT, _Traits, _Alloc> _Buf;
96	tim	1570	#else
97	gezelter	1930	typedef std::basic_filebuf<_CharT, _Traits> _Buf;
98	tim	1570	#endif
99
100	gezelter	1930	static const int FileNotExists = -1;
101	tim	1570	static const int FileIOError = -2;
102
103			public:
104
105			/** Constructs an object of class ifstream. */
106			basic_ifstrstream()
107	gezelter	1930	: std::basic_ios<_CharT, _Traits>(), std::basic_istream<_CharT, _Traits>(0),
108	tim	1570	internalBuf_(NULL), isRead(false) {
109
110			#ifdef IS_MPI
111			//in parallel mode, fall back to istringstream
112	gezelter	1930	std::basic_stringbuf<_CharT, _Traits, _Alloc>* stringBuffer = new std::basic_stringbuf<_CharT, _Traits, _Alloc>();
113	tim	1570	internalBuf_ = stringBuffer;
114			#else
115			//in single version, fall back to ifstream
116	gezelter	1930	std::basic_filebuf<_CharT, _Traits>* fileBuffer = new std::basic_filebuf<_CharT, _Traits>();
117	tim	1570	internalBuf_ = fileBuffer;
118			#endif
119
120			this->init(internalBuf_);
121			isRead = false;
122			}
123
124			/**
125			* Explicit constructor
126			* @filename String containing the name of the file to be opened
127	tim	1572	* @mode Flags describing the requested i/o mode for the file, default value is ios_base::in
128			* @checkFilename Flags indicating checking the file name in parallel
129	tim	1570	*/
130	gezelter	1930	explicit basic_ifstrstream(const char* filename, std::ios_base::openmode mode = std::ios_base::in, bool checkFilename = false)
131			: std::basic_ios<_CharT, _Traits>(), std::basic_istream<_CharT, _Traits>(0),
132	tim	1570	internalBuf_(NULL), isRead(false) {
133
134	gezelter	1930	isRead = internalOpen(filename, mode \| std::ios_base::in, checkFilename);
135	tim	1570	}
136
137			/**
138	tim	1577	* virtual destructor will close the file(in single mode) and clear the stream buffer
139	tim	1570	*/
140			~basic_ifstrstream(){
141			close();
142			delete internalBuf_;
143			internalBuf_ = NULL;
144			}
145
146			/**
147			* Opens a file and associats a buffer with the specified file to perform the i/o operations
148			* (single mode). Master reads a file and brocasts its content to the other slave nodes. After
149			* brocasting, every nodes fall back to stringstream (parallel mode).
150			* @filename String containing the name of the file to be opened
151			* @mode Flags describing the requested i/o mode for the file
152	tim	1572	* @checkFilename Flags indicating checking the file name in parallel
153	tim	1570	*/
154	gezelter	1930	void open(const char* filename, std::ios_base::openmode mode = std::ios_base::in, bool checkFilename = false){
155	tim	1570
156			if (!isRead ) {
157	tim	1572	isRead = internalOpen(filename, mode, checkFilename);
158	tim	1570	}
159			}
160
161			/**
162			* Tests if the stream is currently associated with a valid buffer.
163			* @return true if a file has successfully been opened (single mode) or the whole file is read
164			* and spreaded among all of the processors (parallel mode), otherwise false is returned
165			*/
166			bool is_open ( ) {
167			#ifdef IS_MPI
168			return isRead;
169			#else
170			//single version fall back to ifstream
171			return this->rdbuf()->is_open();
172			#endif
173			}
174
175			/**
176			* In single mode, closes a file. The stream's file buffer is released from its association with
177			* the currently open file. In parallel mode, clean the
178			*/
179			void close() {
180			#ifndef IS_MPI
181			//single version fall back to ifstream
182			if (!this->rdbuf()->close())
183	gezelter	1930	this->setstate(std::ios_base::failbit);
184	tim	1570	#endif
185
186			isRead = false;
187			}
188
189			/**
190			* Gets the stream buffer object associated with the stream
191			* @return A pointer to the stream buffe object(filebuf in single mode, stringbuf in
192			* parallel mode) associated with the stream.
193			*/
194			_Buf* rdbuf() const{
195	tim	1582	return static_cast<_Buf*>(internalBuf_);
196	tim	1570	}
197
198			private:
199
200			/**
201			* Internal function used to open the file
202			* @return true if succesfully opens a file (single mode) or gets the file content (parallel mode)
203			* otherwise return false
204			* @filename String containing the name of the file to be opened
205			* @mode Flags describing the requested i/o mode for the file
206			* @todo use try - catch syntax to make the program more readable
207			*/
208	gezelter	1930	bool internalOpen(const char* filename, std::ios_base::openmode mode, bool checkFilename){
209	tim	1570
210			#ifdef IS_MPI
211			int commStatus;
212			long fileSize;
213			char* fbuf;
214			int filenameLen;
215			int diffFilename;
216			int error;
217	tim	1572	int myRank;
218			int masterNode;
219	tim	1570
220	tim	1572	commStatus = MPI_Comm_rank(MPI_COMM_WORLD, &myRank);
221			masterNode = 0;
222
223			if (myRank == masterNode) {
224	tim	1570
225	tim	1572	if (checkFilename) {
226	tim	1570
227	tim	1572	//check the filename is the same
228			filenameLen = strlen(filename);
229	tim	1583	commStatus = MPI_Bcast(&filenameLen, 1, MPI_INT, masterNode, MPI_COMM_WORLD);
230			commStatus = MPI_Bcast((void*)filename, filenameLen, MPI_CHAR, masterNode, MPI_COMM_WORLD);
231	tim	1570
232	tim	1572	diffFilename = 0;
233	tim	1583	commStatus = MPI_Allreduce(&diffFilename, &error, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD);
234	tim	1572
235			//if file names are different just return false
236			if (error > 0)
237	tim	1570	return false;
238	tim	1572	}
239	tim	1570
240	gezelter	1930	std::ifstream fin(filename, mode);
241			std::basic_stringbuf<_CharT, _Traits, _Alloc>* sbuf;
242	tim	1570
243			if (fin.is_open()) {
244
245	gezelter	1930	fin.seekg(0, std::ios::end);
246	tim	1570	fileSize = fin.tellg();
247	gezelter	1930	fin.seekg(0, std::ios::beg);
248	tim	1583
249	tim	1570	// '\0' need one more char
250			fbuf = new char[fileSize+1];
251
252			assert(fbuf != 0);
253
254			fin.read(fbuf, fileSize);
255
256			if (fin.fail())
257			fileSize = FileIOError;
258
259			//brocasting the file size
260			commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);
261
262			if (fileSize < 0) {
263			fin.close();
264			delete fbuf;
265
266			return false;
267			}
268
269	gezelter	1930	// make a c-style std::string and brocasting it
270	tim	1570	fbuf[fileSize] = '\0';
271			commStatus = MPI_Bcast(fbuf, fileSize + 1, MPI_CHAR, masterNode, MPI_COMM_WORLD);
272
273			//it is safe to delete null pointer
274			delete internalBuf_;
275
276			//initilaize istream
277	gezelter	1930	internalBuf_ = new std::basic_stringbuf<_CharT, _Traits, _Alloc>(fbuf, mode);
278	tim	1570	assert(internalBuf_);
279			this->init(internalBuf_);
280
281			//close the file and delete the buffer
282			fin.close();
283			delete fbuf;
284			}else{
285	gezelter	1930	fileSize = FileNotExists;
286	tim	1570	commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);
287			return false;
288			}
289
290	gezelter	1930	} else{ //slave nodes
291
292	tim	1570	//check file name
293	tim	1572	if (checkFilename) {
294	tim	1583	commStatus = MPI_Bcast(&filenameLen, 1, MPI_INT, masterNode, MPI_COMM_WORLD);
295	tim	1570
296	tim	1572	char * masterFilename = new char[filenameLen];
297			commStatus = MPI_Bcast(masterFilename, filenameLen, MPI_CHAR, masterNode, MPI_COMM_WORLD);
298
299			if( strcmp(masterFilename, filename) == 0)
300			diffFilename = 0;
301			else
302			diffFilename = 1;
303	tim	1570
304	tim	1572	delete masterFilename;
305
306	tim	1583	commStatus = MPI_Allreduce(&diffFilename, &error, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD);
307	tim	1570
308	tim	1572	if (error > 0)
309			return false;
310			}
311	tim	1570	//get file size
312			commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);
313
314			if (fileSize >= 0 ) {
315			fbuf = new char[fileSize+1];
316			assert(fbuf);
317
318			//receive file content
319			commStatus = MPI_Bcast(fbuf, fileSize + 1, MPI_CHAR, masterNode, MPI_COMM_WORLD);
320
321			//it is safe to delete null pointer
322			delete internalBuf_;
323
324			//initilaize istream
325	gezelter	1930	internalBuf_ = new std::basic_stringbuf<_CharT, _Traits, _Alloc>(fbuf, mode);
326	tim	1570	assert(internalBuf_);
327			this->init(internalBuf_);
328
329			delete fbuf;
330
331	gezelter	1930	} else if (fileSize == FileNotExists ) {
332	tim	1570	return false;
333
334			} else if (fileSize == FileIOError ) {
335			return false;
336			}
337			}
338
339			#else
340			//in single version, fall back to ifstream
341	gezelter	1930	std::basic_filebuf<_CharT, _Traits>* fileBuffer = new std::basic_filebuf<_CharT, _Traits>();
342	tim	1570
343	gezelter	1930	//it is safe to delete null pointer
344			delete internalBuf_;
345			internalBuf_ = fileBuffer;
346	tim	1570
347	gezelter	1930	this->init(internalBuf_);
348			if (!fileBuffer->open(filename, mode)) {
349			this->setstate(std::ios_base::failbit);
350			return false;
351			}
352
353	tim	1570	#endif
354
355			return true;
356			}
357
358	gezelter	1930	std::basic_streambuf<_CharT, _Traits>* internalBuf_; /** internal stream buffer */
359	tim	1570	bool isRead; /** file opened flag */
360			};
361
362	gezelter	1930	typedef basic_ifstrstream<char, std::char_traits<char>, std::allocator<char> > ifstrstream;
363	tim	1570	}//namespace oopse
364			#endif //IO_IFSTRSTREAM_HPP