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| #include <iostream>
#include <sstream>
template<typename T,int N =sizeof(T)>
struct reader
{
static T read(std::istream & is)
{
/* BOOST_STATIC_ASSERT
(
sizeof(T)<= sizeof(unsigned long long)
&&
N <= sizeof(unsigned long long)
);*/
unsigned char buf[N] = {0};
is.read(reinterpret_cast<char*>(buf),N);
unsigned long long tmp(0);
for (int i= 0;i<N;++i)
{
tmp |= static_cast<unsigned long long>(buf[i])<<8*(N-1-i);
}
return *reinterpret_cast<T*>(&tmp);
}
};
template<typename T,int N =sizeof(T)>
struct writer
{
static void write(std::ostream & os,const T &t)
{
/* BOOST_STATIC_ASSERT
(
sizeof(T)<= sizeof(unsigned long long)
&&
N <= sizeof(unsigned long long)
);*/
unsigned char buf[N];
const unsigned long long *tmp = reinterpret_cast<const unsigned long long*>(&t);
for (int i= 0;i<N;++i)
{
buf[i] = static_cast<unsigned char>(*tmp >>8*(N-1-i));
}
os.write((char*)buf,N);
}
};
int main(int argc, char* argv[])
{
std::ostringstream os(std::ios::binary);
writer<float>::write(os,100025.8644f);
writer<int>::write(os,10);
writer<char>::write(os,'a');
writer<double>::write(os,125863.4565465);
std::istringstream is(os.str(),std::ios::binary);
std::cout<<reader<float>::read(is)<<std::endl;
std::cout<<reader<int>::read(is)<<std::endl;
std::cout<<reader<char>::read(is)<<std::endl;
double b = reader<double>::read(is);
return 0;
} |
