src/io/basic_ifstrstream.hpp

/*
 * Copyright (C) 2000-2004  Object Oriented Parallel Simulation Engine (OOPSE) project
 * 
 * Contact: oopse@oopse.org
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * of the License, or (at your option) any later version.
 * All we ask is that proper credit is given for our work, which includes
 * - but is not limited to - adding the above copyright notice to the beginning
 * of your source code files, and to any copyright notice that you may distribute
 * with programs based on this work.
 * 
 * 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 Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser 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.
 *
 */

/**
 * @file basic_ifstrstream.hpp
 * @author Teng Lin
 * @date 10/14/2004
 * @version 1.0
 */

#ifndef IO_IFSTRSTREAM_HPP
#define IO_IFSTRSTREAM_HPP

#include <fstream>
#include <sstream>

namespace oopse {
using namespace std;
/**
 * @class basic_ifstrstream basic_ifstrstream.hpp "io/basic_ifstrstream.hpp"
 * @brief 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 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 basic_ios<_CharT, _Traits>                _Basic_ios;
        typedef basic_istream<_CharT, _Traits>            _Base;

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

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

#ifdef IS_MPI         
            //in parallel mode, fall back to istringstream
            basic_stringbuf<_CharT, _Traits, _Alloc>* stringBuffer = new  basic_stringbuf<_CharT, _Traits, _Alloc>();
            internalBuf_ =  stringBuffer;
#else
            //in single version, fall back to ifstream
            basic_filebuf<_CharT, _Traits>* fileBuffer = new  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         
         */
        explicit basic_ifstrstream(const char* filename, ios_base::openmode mode = ios_base::in)
            : basic_ios<_CharT, _Traits>(),  basic_istream<_CharT, _Traits>(0),
              internalBuf_(NULL), isRead(false) {

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

        /**
         *
         */
        ~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
         */
        void open(const char* filename, ios_base::openmode mode = ios_base::in){

            if (!isRead ) {
                isRead = internalOpen();
            }
        }

        /**
         * 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(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 const_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, ios_base::openmode mode){

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

            if (worldRank == masterNode) {

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

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

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

                if (fin.is_open()) {
                    
                    fin.in.seekg(0, ios::end); 
                    fileSize = fin.tellg(); 

                    // '\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 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 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 = FileNoExists;
                    commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);   
                    return false;
                }
               
             } else{
                    //check file name
                    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(sameFilename, error, 1,  MPI_INT,  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 basic_stringbuf<_CharT, _Traits, _Alloc>(fbuf, mode);
                        assert(internalBuf_);
                        this->init(internalBuf_);

                        delete fbuf;

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

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

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

            this->init(fileBuffer);
            if (!fileBuffer->open(filename, mode))
                this->setstate(ios_base::failbit);

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

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

typedef basic_istringstream<char, char_traits<char>, allocator<char> > ifstringstream;
}//namespace oopse
#endif //IO_IFSTRSTREAM_HPP
Revision:	1570
Committed:	Fri Oct 15 07:52:47 2004 UTC (19 years, 8 months ago) by tim
File size:	12174 byte(s)
Log Message:	adding basic_ifstrstream
#	Content
1	/*
2	* Copyright (C) 2000-2004 Object Oriented Parallel Simulation Engine (OOPSE) project
3	*
4	* Contact: oopse@oopse.org
5	*
6	* This program is free software; you can redistribute it and/or
7	* modify it under the terms of the GNU Lesser General Public License
8	* as published by the Free Software Foundation; either version 2.1
9	* of the License, or (at your option) any later version.
10	* All we ask is that proper credit is given for our work, which includes
11	* - but is not limited to - adding the above copyright notice to the beginning
12	* of your source code files, and to any copyright notice that you may distribute
13	* with programs based on this work.
14	*
15	* This program is distributed in the hope that it will be useful,
16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18	* GNU Lesser General Public License for more details.
19	*
20	* You should have received a copy of the GNU Lesser General Public License
21	* along with this program; if not, write to the Free Software
22	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23	*
24	*/
25
26	/**
27	* @file basic_ifstrstream.hpp
28	* @author Teng Lin
29	* @date 10/14/2004
30	* @version 1.0
31	*/
32
33	#ifndef IO_IFSTRSTREAM_HPP
34	#define IO_IFSTRSTREAM_HPP
35
36	#include <fstream>
37	#include <sstream>
38
39	namespace oopse {
40	using namespace std;
41	/**
42	* @class basic_ifstrstream basic_ifstrstream.hpp "io/basic_ifstrstream.hpp"
43	* @brief class provides a stream interface to read data from files.
44	* <p>In single mode, it falls back to ifstream. Don't need to read the whole file into memory.
45	* In parallel mode, the master node will read the whole file and brocast it to other slave nodes.
46	* After brocasting, every node will fall back to stringstream.</p>
47	*
48	* @code
49	* const int MAXLEN = 1024;
50	* char buffer[MAXLEN];
51	* ifstrstream in;
52	* in.open("Shapes.frc");
53	* if (in.is_open) {
54	* in.getline(buffer, MAXLEN);
55	* }
56	* in.close();
57	* @endcode
58	*/
59	template <class _CharT, class _Traits, class _Alloc>
60	class basic_ifstrstream : public basic_istream<_CharT, _Traits> {
61	public:
62	//traits
63	typedef _CharT char_type;
64	typedef typename _Traits::int_type int_type;
65	typedef typename _Traits::pos_type pos_type;
66	typedef typename _Traits::off_type off_type;
67	typedef _Traits traits_type;
68
69	typedef basic_ios<_CharT, _Traits> _Basic_ios;
70	typedef basic_istream<_CharT, _Traits> _Base;
71
72	#ifdef IS_MPI
73	typedef basic_stringbuf<_CharT, _Traits, _Alloc> _Buf;
74	#else
75	typedef basic_filebuf<_CharT, _Traits> _Buf;
76	#endif
77
78	static const int FileNoExists = -1;
79	static const int FileIOError = -2;
80
81	public:
82
83	/** Constructs an object of class ifstream. */
84	basic_ifstrstream()
85	: basic_ios<_CharT, _Traits>(), basic_istream<_CharT, _Traits>(0),
86	internalBuf_(NULL), isRead(false) {
87
88	#ifdef IS_MPI
89	//in parallel mode, fall back to istringstream
90	basic_stringbuf<_CharT, _Traits, _Alloc>* stringBuffer = new basic_stringbuf<_CharT, _Traits, _Alloc>();
91	internalBuf_ = stringBuffer;
92	#else
93	//in single version, fall back to ifstream
94	basic_filebuf<_CharT, _Traits>* fileBuffer = new basic_filebuf<_CharT, _Traits>();
95	internalBuf_ = fileBuffer;
96	#endif
97
98	this->init(internalBuf_);
99	isRead = false;
100	}
101
102	/**
103	* Explicit constructor
104	* @filename String containing the name of the file to be opened
105	* @mode Flags describing the requested i/o mode for the file, default value is ios_base::in
106	*/
107	explicit basic_ifstrstream(const char* filename, ios_base::openmode mode = ios_base::in)
108	: basic_ios<_CharT, _Traits>(), basic_istream<_CharT, _Traits>(0),
109	internalBuf_(NULL), isRead(false) {
110
111	isRead = internalOpen(filename, mode \| ios_base::in);
112	}
113
114	/**
115	*
116	*/
117	~basic_ifstrstream(){
118	close();
119	delete internalBuf_;
120	internalBuf_ = NULL;
121	}
122
123	/**
124	* Opens a file and associats a buffer with the specified file to perform the i/o operations
125	* (single mode). Master reads a file and brocasts its content to the other slave nodes. After
126	* brocasting, every nodes fall back to stringstream (parallel mode).
127	* @filename String containing the name of the file to be opened
128	* @mode Flags describing the requested i/o mode for the file
129	*/
130	void open(const char* filename, ios_base::openmode mode = ios_base::in){
131
132	if (!isRead ) {
133	isRead = internalOpen();
134	}
135	}
136
137	/**
138	* Tests if the stream is currently associated with a valid buffer.
139	* @return true if a file has successfully been opened (single mode) or the whole file is read
140	* and spreaded among all of the processors (parallel mode), otherwise false is returned
141	*/
142	bool is_open ( ) {
143	#ifdef IS_MPI
144	return isRead;
145	#else
146	//single version fall back to ifstream
147	return this->rdbuf()->is_open();
148	#endif
149	}
150
151	/**
152	* In single mode, closes a file. The stream's file buffer is released from its association with
153	* the currently open file. In parallel mode, clean the
154	*/
155	void close() {
156	#ifndef IS_MPI
157	//single version fall back to ifstream
158	if (!this->rdbuf()->close())
159	this->setstate(ios_base::failbit);
160	#endif
161
162	isRead = false;
163	}
164
165	/**
166	* Gets the stream buffer object associated with the stream
167	* @return A pointer to the stream buffe object(filebuf in single mode, stringbuf in
168	* parallel mode) associated with the stream.
169	*/
170	_Buf* rdbuf() const{
171	return const_cast<_Buf*>(internalBuf_);
172	}
173
174	private:
175
176	/**
177	* Internal function used to open the file
178	* @return true if succesfully opens a file (single mode) or gets the file content (parallel mode)
179	* otherwise return false
180	* @filename String containing the name of the file to be opened
181	* @mode Flags describing the requested i/o mode for the file
182	* @todo use try - catch syntax to make the program more readable
183	*/
184	bool internalOpen(const char* filename, ios_base::openmode mode){
185
186	#ifdef IS_MPI
187	int commStatus;
188	long fileSize;
189	char* fbuf;
190	int filenameLen;
191	int diffFilename;
192	int error;
193
194	if (worldRank == masterNode) {
195
196	//check the filename is the same
197	filenameLen = strlen(filename);
198	commStatus = MPI_Bcast(filenameLen, 1, MPI_INT, masterNode, MPI_COMM_WORLD);
199	commStatus = MPI_Bcast(filename, filenameLen, MPI_CHAR, masterNode, MPI_COMM_WORLD);
200
201	diffFilename = 0;
202	commStatus = MPI_Allreduce(sameFilename, error, 1, MPI_INT, MPI_COMM_WORLD);
203
204	//if file names are different just return false
205	if (error > 0)
206	return false;
207
208	ifstream fin(filename, mod);
209	basic_stringbuf<_CharT, _Traits, _Alloc>* sbuf;
210
211	if (fin.is_open()) {
212
213	fin.in.seekg(0, ios::end);
214	fileSize = fin.tellg();
215
216	// '\0' need one more char
217	fbuf = new char[fileSize+1];
218
219	assert(fbuf != 0);
220
221	fin.read(fbuf, fileSize);
222
223	if (fin.fail())
224	fileSize = FileIOError;
225
226	//brocasting the file size
227	commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);
228
229	if (fileSize < 0) {
230	fin.close();
231	delete fbuf;
232
233	return false;
234	}
235
236	// make a c-style string and brocasting it
237	fbuf[fileSize] = '\0';
238	commStatus = MPI_Bcast(fbuf, fileSize + 1, MPI_CHAR, masterNode, MPI_COMM_WORLD);
239
240	//it is safe to delete null pointer
241	delete internalBuf_;
242
243	//initilaize istream
244	internalBuf_ = new basic_stringbuf<_CharT, _Traits, _Alloc>(fbuf, mode);
245	assert(internalBuf_);
246	this->init(internalBuf_);
247
248	//close the file and delete the buffer
249	fin.close();
250	delete fbuf;
251	}else{
252	fileSize = FileNoExists;
253	commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);
254	return false;
255	}
256
257	} else{
258	//check file name
259	commStatus = MPI_Bcast(filenameLen, 1, MPI_INT, masterNode, MPI_COMM_WORLD);
260
261	char * masterFilename = new char[filenameLen];
262	commStatus = MPI_Bcast(masterFilename, filenameLen, MPI_CHAR, masterNode, MPI_COMM_WORLD);
263
264	if( strcmp(masterFilename, filename) == 0)
265	diffFilename = 0;
266	else
267	diffFilename = 1;
268
269	delete masterFilename;
270
271	commStatus = MPI_Allreduce(sameFilename, error, 1, MPI_INT, MPI_COMM_WORLD);
272
273	if (error > 0)
274	return false;
275
276	//get file size
277	commStatus = MPI_Bcast(&fileSize, 1, MPI_LONG, masterNode, MPI_COMM_WORLD);
278
279	if (fileSize >= 0 ) {
280	fbuf = new char[fileSize+1];
281	assert(fbuf);
282
283	//receive file content
284	commStatus = MPI_Bcast(fbuf, fileSize + 1, MPI_CHAR, masterNode, MPI_COMM_WORLD);
285
286	//it is safe to delete null pointer
287	delete internalBuf_;
288
289	//initilaize istream
290	internalBuf_ = new basic_stringbuf<_CharT, _Traits, _Alloc>(fbuf, mode);
291	assert(internalBuf_);
292	this->init(internalBuf_);
293
294	delete fbuf;
295
296	} else if (fileSize == FileNoExists ) {
297	return false;
298
299	} else if (fileSize == FileIOError ) {
300	return false;
301	}
302	}
303
304	#else
305	//in single version, fall back to ifstream
306	basic_filebuf<_CharT, _Traits>* fileBuffer = new basic_filebuf<_CharT, _Traits>();
307
308	this->init(fileBuffer);
309	if (!fileBuffer->open(filename, mode))
310	this->setstate(ios_base::failbit);
311
312	//it is safe to delete null pointer
313	delete internalBuf_;
314
315	internalBuf_ = fileBuffer;
316	#endif
317
318	return true;
319	}
320
321	basic_streambuf<_CharT, _Traits>* internalBuf_; /** internal stream buffer */
322	bool isRead; /** file opened flag */
323	};
324
325	typedef basic_istringstream<char, char_traits<char>, allocator<char> > ifstringstream;
326	}//namespace oopse
327	#endif //IO_IFSTRSTREAM_HPP