boinc/lib/mfile.h

58 lines
2.0 KiB
C++

// Berkeley Open Infrastructure for Network Computing
// http://boinc.berkeley.edu
// Copyright (C) 2005 University of California
//
// This 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.
//
// This software 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.
//
// To view the GNU Lesser General Public License visit
// http://www.gnu.org/copyleft/lesser.html
// or write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#ifndef _MFILE_
#define _MFILE_
#include <cstdio>
#include <cstdarg>
// MFILE provides memory-buffered output with a FILE-type interface.
// BOINC uses this in a couple of places:
// 1) in the GUI RPC system (since in Windows you can't fdopen a socket)
// 2) in the API, to support a primitive form of checkpointing:
// Write all your output (and restart file) to MFILEs.
// The output is buffered in memory.
// Then close or flush all the MFILEs;
// all the buffers will be flushed to disk, almost atomically.
class MFILE {
char* buf; // NULL-terminated
int len;
FILE* f;
public:
MFILE();
~MFILE();
int open(const char* path, const char* mode);
int _putchar(char);
int puts(const char*);
int vprintf(const char* format, va_list);
int printf(const char* format, ...);
size_t write(const void *, size_t size, size_t nitems);
int close();
int flush();
long tell() const;
void get_buf(char*&, int&);
// get the MFILE's internal buffer and its length.
// The caller assumes ownership of the buffer and must free() it.
// The MFILE's buffer is set to empty
};
#endif