// -*- C++ -*-
// Boost general library 'format' ---------------------------
// See http://www.boost.org for updates, documentation, and revision history.
// Copyright (c) 2001 Samuel Krempp
// krempp@crans.ens-cachan.fr
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// several suggestions from Jens Maurer
// ------------------------------------------------------------------------------
// bench_variants.cc : do the same task, with snprintf, stream, and format
// and compare their times.
// This benchmark is provided purely for information.
// It might not even compile as-is,
// or not give any sensible results.
// (e.g., it expects sprintf to be POSIX compliant)
// ------------------------------------------------------------------------------
#include <iostream>
#include <iomanip>
#include <cstdio> // sprintf
#include <cstring>
#include <fstream>
#include <cmath> // floor
#include <boost/timer.hpp>
#include <boost/format.hpp>
//#define knelson
#ifdef knelson
namespace KNelson {
#include "boost/format3.hpp"
}
#endif
// portable /dev/null stream equivalent, by James Kanze, http://www.gabi-soft.de
class NulStreambuf : public std::streambuf
{
public:
NulStreambuf() {
setp( dummyBuffer , dummyBuffer + 64 ) ;
}
virtual int overflow( int c );
virtual int underflow();
private:
char dummyBuffer[ 64 ] ;
} ;
class NulStream : public std::basic_ostream<char, std::char_traits<char> >
{
public:
NulStream();
virtual ~NulStream();
NulStreambuf* rdbuf() {
return static_cast< NulStreambuf* >(
((std::basic_ostream<char, std::char_traits<char> > *) this) -> rdbuf() ) ;
}
} ;
//-------------------------------------------------------------------------------------
// NulStream implementation
NulStream::NulStream() : std::basic_ostream<char, std::char_traits<char> > (NULL) {
init( new NulStreambuf ) ;
}
NulStream::~NulStream() {
delete rdbuf() ;
}
int NulStreambuf::underflow(){ return std::ios::traits_type::eof();
}
int NulStreambuf::overflow( int c ){
setp( dummyBuffer , dummyBuffer + 64 ) ;
return (c == std::ios::traits_type::eof()) ? '\0' : c ;
}
// -------------------------------------------------------------------------------------
static int NTests = 300000;
//static std::stringstream nullStream;
static NulStream nullStream;
static double tstream, tpf;
//static const std::string fstring="%3$#x %1$20.10E %2$g %3$d \n";
static const std::string fstring="%3$0#6x %1$20.10E %2$g %3$0+5d \n";
static const double arg1=45.23;
static const double arg2=12.34;
static const int arg3=23;
static const std::string res =
"0x0017 4.5230000000E+01 12.34 +0023 \n";
//static const std::string res = "23.0000 4.5230000000E+01 12.34 23 \n";
void test_snprintf();
void test_nullstream();
void test_opti_nullstream();
void test_parsed_once_format();
void test_reused_format();
void test_format();
void test_try1();
void test_try2();
#ifdef knelson
void test_format3();
#endif
int main(int argc, char * argv[]) {
using namespace boost;
using namespace std;
const string::size_type npos = string::npos;
string choices="";
if(1<argc) {
choices = (argv[1]); // profiling is easier launching only one.
NTests = 1000*1000; // andmoreprecise with many iterations
cout << "choices (" << choices << ") \n";
}
if(choices=="" || choices.find('p') !=npos)
test_snprintf();
if(choices=="" || choices.find('n') !=npos)
test_nullstream();
if(choices=="" || choices.find('1') !=npos)
test_parsed_once_format();
if(choices=="" || choices.find('r') !=npos)
test_reused_format();
if(choices=="" || choices.find('f') !=npos)
test_format();
if(choices.find('t') !=npos)
test_try1();
if(choices.find('y') !=npos)
test_try2();
if(choices.find('o') !=npos)
test_opti_nullstream();
#ifdef knelson
if(choices=="" || choices.find('k') !=npos)
test_format3();
#endif
return 0;
}
void test_snprintf()
{
using namespace std;
// Check that snpintf is Unix98 compatible on the platform :
char * buf = new char[4000];
sprintf(buf, fstring.c_str(), arg1, arg2, arg3);
if( strncmp( buf, res.c_str(), res.size()) != 0 ) {
cerr << endl << buf;
}
// time the loop :
boost::timer chrono;
for(int i=0; i<NTests; ++i) {
sprintf(buf, fstring.c_str(), arg1, arg2, arg3);
}
tpf=chrono.elapsed();
cout << left << setw(20) <<"printf time"<< right <<":" << tpf << endl;
}
void test_try1()
{
using namespace std;
boost::io::basic_oaltstringstream<char> oss;
oss << boost::format(fstring) % arg1 % arg2 % arg3;
boost::timer chrono;
int dummy=0;
for(int i=0; i<NTests; ++i) {
dummy += oss.cur_size();
}
double t = chrono.elapsed();
cout << left << setw(20) <<"try1 time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf "
<< ", = " << t / tstream << " * nullStream \n";
}
void test_try2()
{
using namespace std;
boost::io::basic_oaltstringstream<char> oss;
oss << boost::format(fstring) % arg1 % arg2 % arg3;
oss << "blas 34567890GGGGGGGGGGGGGGGGGGGGGGGGGGGGggggggggggggggggggggggggggg " << endl;
string s = oss.cur_str();
oss << s << s << s;
oss.clear_buffer();
oss << s << s;
s = oss.cur_str();
boost::timer chrono;
int dummy=0;
for(int i=0; i<NTests; ++i) {
dummy += oss.cur_size();
}
double t = chrono.elapsed();
cout << left << setw(20) <<"try2 time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf "
<< ", = " << t / tstream << " * nullStream \n";
}
void do_stream(std::ostream& os) {
using namespace std;
std::ios_base::fmtflags f = os.flags();
os << hex << showbase << internal << setfill('0') << setw(6) << arg3
<< dec << noshowbase << right << setfill(' ')
<< " "
<< scientific << setw(20) << setprecision(10) << uppercase << arg1
<< setprecision(6) << nouppercase ;
os.flags(f);
os << " " << arg2 << " "
<< showpos << setw(5) << internal << setfill('0') << arg3 << " \n" ;
os.flags(f);
}
void test_nullstream()
{
using namespace std;
boost::timer chrono;
boost::io::basic_oaltstringstream<char> oss;
{
do_stream(oss);
if(oss.str() != res ) {
cerr << endl << oss.str() ;
}
}
for(int i=0; i<NTests; ++i) {
do_stream(nullStream);
}
// for(int i=0; i<NTests; ++i) {
// std::ios_base::fmtflags f0 = nullStream.flags();
// nullStream << hex << showbase << arg3
// << dec << noshowbase << " "
// << scientific << setw(20) << setprecision(10) << uppercase << arg1
// << setprecision(0);
// nullStream.flags(f0);
// nullStream << " " << arg2 << " " << arg3 << " \n" ;
// }
double t = chrono.elapsed();
cout << left << setw(20) <<"ostream time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf \n";
tstream = t;
}
void test_opti_nullstream()
{
using namespace std;
boost::timer chrono;
boost::io::basic_oaltstringstream<char> oss;
//static const std::string fstring="%3$#x %1$20.10E %2$g %3$d \n";
std::ios_base::fmtflags f0 = oss.flags(), f1, f2;
streamsize p0 = oss.precision();
{
oss << hex << showbase;
f1 = oss.flags();
oss << arg3;
oss.flags(f0);
oss << " " << scientific << setw(20) << setprecision(10) << uppercase;
f2 = oss.flags();
oss << arg1;
oss.flags(f0); oss.precision(p0);
oss << " " << arg2 << " " << arg3 << " \n" ;
if(oss.str() != res ) {
cerr << endl << oss.str() ;
}
}
for(int i=0; i<NTests; ++i) {
nullStream.flags(f1);
nullStream << arg3;
nullStream << setw(20) << setprecision(10);
nullStream.flags(f2);
nullStream << arg1;
nullStream.flags(f0); nullStream.precision(p0);
nullStream << " " << arg2 << " " << arg3 << " \n" ;
}
double t = chrono.elapsed();
cout << left << setw(20) <<"opti-stream time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf \n";
// tstream = t;
}
void test_parsed_once_format()
{
using namespace std;
static const boost::format fmter(fstring);
boost::io::basic_oaltstringstream<char> oss;
oss << boost::format(fmter) % arg1 % arg2 % arg3 ;
if( oss.str() != res ) {
cerr << endl << oss.str();
}
// not only is the format-string parsed once,
// but also the buffer of the internal stringstream is already allocated.
boost::timer chrono;
for(int i=0; i<NTests; ++i) {
nullStream << boost::format(fmter) % arg1 % arg2 % arg3;
}
double t=chrono.elapsed();
cout << left << setw(20) <<"parsed-once time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf "
<< ", = " << t / tstream << " * nullStream \n";
}
void test_reused_format()
{
using namespace std;
boost::io::basic_oaltstringstream<char> oss;
oss << boost::format(fstring) % arg1 % arg2 % arg3;
if(oss.str() != res ) {
cerr << endl << oss.str();
}
boost::timer chrono;
boost::format fmter;
for(int i=0; i<NTests; ++i) {
nullStream << fmter.parse(fstring) % arg1 % arg2 % arg3;
}
double t = chrono.elapsed();
cout << left << setw(20) <<"reused format time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf "
<< ", = " << t / tstream << " * nullStream \n";
}
void test_format()
{
using namespace std;
boost::io::basic_oaltstringstream<char> oss;
oss << boost::format(fstring) % arg1 % arg2 % arg3;
if(oss.str() != res ) {
cerr << endl << oss.str();
}
boost::timer chrono;
for(int i=0; i<NTests; ++i) {
nullStream << boost::format(fstring) % arg1 % arg2 % arg3;
}
double t = chrono.elapsed();
cout << left << setw(20) <<"format time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf "
<< ", = " << t / tstream << " * nullStream \n";
}
#ifdef knelson
void test_format3()
{
using namespace std;
boost::io::basic_oaltstringstream<char> oss;
oss << KNelson::boost::format(fstring.c_str(), arg1, arg2, arg3);
if(oss.str() != res ) {
cerr << endl << oss.str();
}
boost::timer chrono;
for(int i=0; i<NTests; ++i) {
nullStream << KNelson::boost::format(fstring.c_str(), arg1, arg2, arg3);
}
double t = chrono.elapsed();
cout << left << setw(20) <<"format3 time"<< right <<":" << setw(5) << t
<< ", = " << t / tpf << " * printf "
<< ", = " << t / tstream << " * nullStream \n" ;
}
#endif
