#include <stdio.h>


#if defined(sparc) || defined(stellar) || defined(applec) || defined(THINK_C) || defined(hpux) || defined(IBMRS6000)
#define BIGENDIAN   1
#endif /* sun || sparc || stellar || applec || THINK_C */

/*
 * Allow for both big-endian (sgi) and little-endian (dec)
 * mips machines.
 */
#if defined(MIPSEL) || defined(_MIPSEL) || defined(__MIPSEL)
#define BIGENDIAN 0
#endif
#if defined(MIPSEB) || defined(_MIPSEB) || defined(__MIPSEB)
#define BIGENDIAN 1
#endif

/* DEC Alpha machines. */
#if defined(__alpha)
#define BIGENDIAN 0
#endif

/* Various Intel chips. */
#if defined(m386) || defined(M_I86) || defined(MSDOS) || defined(I860) || defined(PVS) || defined (_M_IX86) || defined(__i386__)
#define BIGENDIAN   0
#endif /* m386 || M_I86 */

#ifdef vax
#define BIGENDIAN   0
#endif /* vax */


#if (BIGENDIAN == 1)
typedef struct ieeedouble {
    unsigned int sign:1;
    unsigned int exp:11;
    unsigned int mant:20;
    unsigned int mant2:32;
} ieeedouble;
typedef struct ieeefloat {
    unsigned int sign:1;
    unsigned int exp:8;
    unsigned int mant:23;
} ieeefloat;
#else /* BIGENDIAN 0  or little endian */
typedef struct ieeedouble {
    unsigned int mant2:32;
    unsigned int mant:20;
    unsigned int exp:11;
    unsigned int sign:1;
} ieeedouble;
typedef struct ieeefloat {
    unsigned int mant:23;
    unsigned int exp:8;
    unsigned int sign:1;
} ieeefloat;
#endif  /* BIGENDIAN */


typedef struct ieeedouble nativedouble;
typedef struct ieeefloat nativefloat;

typedef union {
    ieeedouble  ieee;
    nativedouble    native;
    char        b[8];
    double      d;
} double_type;

typedef union {
    ieeefloat   ieee;
    nativefloat native;
    char        b[4];
    float       f;
} float_type;

#define ISFRACTION(e)   (1022 - 4 <= (e) && (e) <= 1022 + 15)
#define EXTRACTFRACTION(dp) \
   (((unsigned)(1L<<30)|((unsigned)(dp)->native.mant<<10)| \
   ((dp)->native.mant2>>22)) >> (1022+15-(dp)->native.exp))

#define EXTRACTMANT(dp) \
   (((unsigned)(dp)->native.mant<<32)|((dp)->native.mant2))

#define EXTRACTEXPONENT(dp) ((dp)->native.exp)



#define word unsigned int
#define dword unsigned long
#define byte unsigned char
void pf( int signo, int exp, dword mant);


int main( void )
{
	int	i,j;
	static float    nf[]={ 234.12345678, -5.75, 9.99e9, 1.1e-5 };
	static double    nd[]={ 234.12345678, -5.75, 9.99e9, 1.1e-5 };
	FILE	*f;
	register int exp;
	register long n, an;
	int fract;

	union
	{
		unsigned long l;
		char c[sizeof(long)];
	} u;

	float_type	ft[4];
	double_type	dt[4];

#if (BIGENDIAN == 1)
	fprintf(stderr,"host is bigendian\n");
#else
	fprintf(stderr,"host is littleendian\n");
#endif


	if (sizeof(long) > 4)
		u.l = 0x0102030405060708;
	else
		u.l = 0x01020304;
	for (i=0; i < sizeof(long); i++)
		fprintf(stderr,"%c",u.c[i]+'0');
	fprintf(stderr,"\n");


#if (BIGENDIAN == 1)
		fprintf(stderr,"creating sun4f\n");
		f=fopen("sun4f","w");
#else
		fprintf(stderr,"creating i86pcf\n");
		f=fopen("i86pcf","w");
#endif


	for(i=0;i<4;i++)
	{
		ft[i].f = nf[i];
		fprintf(stderr, "f: %f\n", ft[i].f);
		pf(ft[i].native.sign, ft[i].native.exp, ft[i].native.mant);
		fwrite( &ft[i].b, sizeof(float), 1, f);
	}
	for(i=0;i<4;i++)
	{
		dt[i].d = nd[i];
		fprintf(stderr, "d: %g\n", dt[i].d);
		fwrite( &dt[i].d, sizeof(double), 1, f);
	}
	fclose(f);

#if (BIGENDIAN == 1)
		fprintf(stderr,"host sun4, open i86pcf\n");
		f=fopen("i86pcf","r");
#else
		fprintf(stderr,"host i86pc, open sun4f\n");
		f=fopen("sun4f","r");
#endif
	if ( NULL == f )
	{
		perror("fopen");
		fprintf(stderr,"Please, create the other endian file\n");
		exit(1);
	}

	for(i=0;i<4;i++)
	{
		for( j=0; j<sizeof(float); j++)
		{
			fread(&ft[i].b[sizeof(float)-1-j],1,1,f);
		}
		fprintf(stderr, "f: %f\n", ft[i].f);
	}

	for(i=0;i<4;i++)
	{
		double_type *dp;
		for( j=0; j<sizeof(double); j++)
		{
			fread(&dt[i].b[sizeof(double)-1-j],1,1,f);
		}
		fprintf(stderr, "\nd: %g\n", dt[i].d);
		fprintf(stderr, "mant2: %d\n", dt[i].native.mant2);
		fprintf(stderr, "mant : %d\n", dt[i].native.mant);
		fprintf(stderr, "exp  : %d\n", dt[i].native.exp);
		fprintf(stderr, "sign  : %d\n", dt[i].native.sign);

		dp=&dt[i];

		exp=EXTRACTEXPONENT(dp);

		fprintf(stderr, "exp       : %d\n", exp);
		fprintf(stderr, "exp-1023  : %d\n", exp-1023);
		fprintf(stderr, "frac : %d\n", EXTRACTFRACTION(&dt[i]));

		{
			unsigned long mant;
			unsigned long long mantu;
			unsigned long long mantd;
			unsigned long long k;
			int j;

			mantu=1;
			mantd=1;
			k=1;
			mant=dt[i].native.mant;
			fprintf(stderr, "mant : 0x%lX\nmant : ", mant);
			for (j=1; j<= 20; j++)
			{
				k <<= 1;
				if ( 0 != (1 & (mant>>(20-j))))
				{
					fprintf(stderr, "1");
					mantu *= (k/mantd);
					mantu ++;
					mantd = k;
				}
				else
					fprintf(stderr, "0");
			}
			fprintf(stderr, "\nmant : %llu/%llu\n", mantu, mantd);

			mant=dt[i].native.mant2;
			fprintf(stderr, "mant : 0x%lX\nmant : ", mant);

			for (j=1; j<= 32; j++)
			{
				k <<= 1;
				if ( 0 != (1 & (mant>>(32-j))))
				{
					fprintf(stderr, "1");
					mantu *= (k/mantd);
					mantu ++;
					mantd = k;
				}
				else
					fprintf(stderr, "0");
			}

			fprintf(stderr, "\nmant : %llu/%llu\n", mantu, mantd);

			fprintf(stderr, "%g = %c ( %llu / %llu ) * 2^%d\n",
				dt[i].d,
				dt[i].native.sign == 1 ? '-' : ' ',
				mantu,mantd,exp-1023);

		}
	}


	fclose(f);
	return(0);
}


void pf( int signo, int exp, dword mant)
{

    int   i;
    int   tempexpo;
    word  entero10 = 0;
    word  decimal10 = 0;

    exp  -= 127;
	mant |= 0x800000U;

    tempexpo=exp;
    entero10 = 0;
    decimal10 = 0;

    /* calculamos la parte entera. */
    for (i=0; tempexpo>=0; i++ ) {
        entero10 = entero10*2 + ((mant & (0x800000>>i)) ? 1 : 0);
        tempexpo--;
        if( i >= 23 )
            break;
    }

    /* aqui calculamos la parte decimal
       decimal10 contiene 9 digitos significativos
    */
    if( i<23) {
        int valbit= 500000000; /* inicialmente el valor 0.5 */
        for(; exp < -1; exp++)
            valbit/=2;

        for(; i<23; i++) {
            if( i>=0)
                decimal10 = decimal10 +
                     ((mant & (0x800000>>i)) ? valbit : 0);
            valbit/=2;
        }
    }

    /* presentar numero en string ascii */
    printf("printfloat: %c%u.%09.9u\n", (signo?'-' : ' '), entero10, decimal10);

	fflush(stdout);

}