#include "image_sio.h"
#include "lib_functions.h"
/*
int is_big_endian_(void);
int is_big_endian__(void);
void die (char *, char *);
void cross3_(double *, double *, double *);
void    get_seconds(struct PRM, double *, double *);
*/
/*---------------------------------------------------------------*/
/* check endian of machine 	*/
/* 1 if big; -1 if little	*/
int is_big_endian_()
{
	union
	{
	long l;
	char c[sizeof (long) ];
	} u;
	u.l = 1;
	return( u.c[sizeof(long) - 1] ==  1 ? 1 : -1);
}
int is_big_endian__()
{
	return is_big_endian_();
}
/*---------------------------------------------------------------*/
/*---------------------------------------------------------------*/
/* write out error message and exit 				*/
/* use two strings to allow more complicated error messages 	*/
void die (char *s1, char *s2)
{
	fprintf(stderr," %s %s \n",s1,s2);
	exit(1);
}
/*---------------------------------------------------------------*/
/************************************************************************
* cross3 is a routine to take the cross product of 3-D vectors         *
*************************************************************************/
void cross3_(double *a, double *b, double *c)

/* input and output vectors  having 3 elements */ 

{

       c[0] =  (a[1]*b[2]) - (a[2]*b[1]);
       c[1] = (-a[0]*b[2]) + (a[2]*b[0]);
       c[2] = (a[0]*b[1]) - (a[1]*b[0]);

}
/*---------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* find seconds		*/
void	get_seconds(struct PRM p, double *start, double *end)
{
int	m;
double	dyear, doy;
double	n_secs_day;

n_secs_day = 24.0*60.0*60.0;
dyear = 1000.0*floor(p.SC_clock_start/1000.0);
doy = p.SC_clock_start - dyear;
m = p.nrows - p.num_valid_az;

*start = n_secs_day*doy + (1.0*m)/(2.0*p.prf);
*end = *start + p.num_patches * p.num_valid_az/p.prf;

}
/*---------------------------------------------------------------------------*/