Hey All, i'm doing this project in c++ consisting in reading an mp3 file and extracting the informations within it. Thing is i'm starting to be pissed by this persistent error that stops me from test the code.
This error is, as far as my (limited) knowledge goes, caused by the passing of a stream parameter to a function by copy. Considering that, i'm passing the parameters by reference, but still the error subsists...
I would be very grateful if someone give me a hand here. Thanks in advance, here's the code:
header :
#endif
#ifndef VISITOR_H
#define VISITOR_H
#include <stdio.h>
#include <sstream>
#include <fstream>
#include <list>
using namespace std;
class FrameVisitor : public Frame
{
list<Frame> frames;
public:
FrameVisitor();
list<Frame> get_frames(fstream& file);
bool getFirstFrame(Frame& f);
void WriteFrame(Frame f, FILE * dst);
int fastValidation(Frame f);
};
#endif
implementation:
#include "Mp3.h"
using namespace std;
FrameVisitor::FrameVisitor()
{
Frame();
frames = get_frames(myfile);
}
void FrameVisitor::WriteFrame(Frame f, FILE * dst)
{
size_t num_bytes = f.getLength(); //size_t size var de instancia de Frame.
memcpy(dst,f.frame,num_bytes);
//Duvida: É preciso criar um novo file com o mm nome, escrever la a frame e depois o resto?
//ou basta escrever por cima como tou a fazer aqui?
}
list<Frame> FrameVisitor::get_frames(fstream& myfile)
{
char * memblock = new char [4]; //1º 4 bytes da frame...header.
char * start = memblock;
int i = 0;
char c;
list<Frame> lst;
Frame f;
while(!myfile.eof()){
while(i<4){
c=myfile.get();
f.addByte(c);
memblock[i++]=c;
}
myfile.seekg(-4,ios::cur);
i = 0;
if((memblock[0] == 0xFF) && ((memblock[1])& 0xE0) == 0xE0)
{
f.getFrame(myfile);//Pedaço do ficheiro ate encontrar prox header.
//Construir uma frame para meter na lista.
if(fastValidation(f) == 0)
{
lst.push_back((f));
memblock = start;
}
else
{
f.clear();
memblock = start;
myfile.seekg(1,ios::cur);
}
}
myfile.seekg(1,ios::cur);
memblock = start;
f.clear();
}
return lst;
}
int FrameVisitor::fastValidation(Frame f)
{
if((f.getVersion() ==1) || (f.getLayer() == 0) || (f.getBitrate() == 0 || f.getBitrate() == 15) || (f.getFrequency() == 3))
return -1;
return 0;
}
bool FrameVisitor::getFirstFrame(Frame& f)
{
if(!frames.empty())
{
f = frames.front();
return true;
}
return false;
}
The error message goes:
1>------ Build started: Project: Trabalho2, Configuration: Debug Win32 ------
1>Compiling...
1>Mp3.cpp
1>FrameVisitor.cpp
1>c:\program files\microsoft visual studio 8\vc\include\fstream(933) : error C2248: 'std::basic_ios<_Elem,_Traits>::basic_ios' : cannot access private member declared in class 'std::basic_ios<_Elem,_Traits>'
1> with
1> [
1> _Elem=char,
1> _Traits=std::char_traits<char>
1> ]
1> c:\program files\microsoft visual studio 8\vc\include\ios(151) : see declaration of 'std::basic_ios<_Elem,_Traits>::basic_ios'
1> with
1> [
1> _Elem=char,
1> _Traits=std::char_traits<char>
1> ]
1> This diagnostic occurred in the compiler generated function 'std::basic_fstream<_Elem,_Traits>::basic_fstream(const std::basic_fstream<_Elem,_Traits> &)'
1> with
1> [
1> _Elem=char,
1> _Traits=std::char_traits<char>
1> ]
1>Generating Code...
1>Build log was saved at "file://c:\Users\Bruno\Desktop\ISEL\PICC\Trabalhos\Trabalho2\Trabalho2\Debug\BuildLog.htm"
1>Trabalho2 - 1 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========