#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include <sys/time.h>
#include <time.h>
#include <alloca.h>

#ifndef NUM_ITER
#define NUM_ITER 100000
#endif
#ifndef STRING_LEN
#define STRING_LEN 1000
#endif

#define BUFLEN (STRING_LEN * 10 + 1)

char *
str_add(char *s, char *lim, const char *a)
{
	int c;

	do {
		if (s >= lim) {
			s = lim - 1;
			c = 0;
		} else
			c = *a++;
		*s++ = c;
	} while (c);

	return s;
}

void
sub_time(struct timeval *time, struct timeval *begin)
{
	time->tv_sec -= begin->tv_sec;
	time->tv_usec -= begin->tv_usec;
	if (time->tv_usec < 0) {
		time->tv_usec += 1000000;
		--time->tv_sec;
	}
	printf("%4ld.%06ld  ", time->tv_sec, time->tv_usec);
}

int main()
{
    struct timeval start, end;
    char *buffer = (char *)alloca(BUFLEN);
    int i, l;
    char *STRING = (char *)alloca(STRING_LEN + 1);
    memset(STRING, '1', STRING_LEN);

  for(l = STRING_LEN; l >= 10; (l > 100) ? (l -= 100) : (l -= 10)) {
	  STRING[l] = 0;
// WAY1
    gettimeofday(&start, NULL);
    for( i=0; i<NUM_ITER; ++i )
    {
	strcpy( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
	strcat( buffer, STRING );
    }
    gettimeofday(&end, NULL);
    sub_time(&end, &start);

// WAY2
    gettimeofday(&start, NULL);
    for( i=0; i<NUM_ITER; ++i )
    {
	sprintf( buffer, "%s%s%s%s%s%s%s%s%s%s", STRING, STRING, STRING, STRING,
		STRING, STRING, STRING, STRING, STRING, STRING );
    }
    gettimeofday(&end, NULL);
    sub_time(&end, &start);

// WAY2.5
    gettimeofday(&start, NULL);
    for( i=0; i<NUM_ITER; ++i )
    {
	snprintf( buffer, BUFLEN, "%s%s%s%s%s%s%s%s%s%s", STRING, STRING, STRING, STRING,
		STRING, STRING, STRING, STRING, STRING, STRING );
    }
    gettimeofday(&end, NULL);
    sub_time(&end, &start);

// WAY3
    gettimeofday(&start, NULL);
    for( i=0; i<NUM_ITER; ++i )
    {
	char *pointer=buffer;
	char *const limit=buffer+BUFLEN;

	buffer[0]='\0';
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
	pointer=str_add( buffer, limit, STRING );
    }
    gettimeofday(&end, NULL);
    sub_time(&end, &start);

// WAY4
    gettimeofday(&start, NULL);
    for( i=0; i<NUM_ITER; ++i )
    {
	char *pointer=buffer;

	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
	pointer=stpcpy(pointer, STRING);
    }
    gettimeofday(&end, NULL);
    sub_time(&end, &start);

    printf("%4d\n", l);
  }
    return 0;
}