hdf5/config/cmake/ConversionTests.c

#ifdef H5_LDOUBLE_TO_LONG_SPECIAL_TEST

int main(void)
{
    long double         ld = 20041683600089727.779961L;
    long                ll;
    unsigned long       ull;
    unsigned char       s[16];
    unsigned char       s2[8];
    int                 ret = 1;

    if(sizeof(long double) == 16 && sizeof(long) == 8) {
	/*make sure the long double type has 16 bytes in size and
	 * 11 bits of exponent.  If it is,
	 *the bit sequence should be like below.  It's not
	 *a decent way to check but this info isn't available. */
	memcpy(s, &ld, 16);
	if(s[0]==0x43 && s[1]==0x51 && s[2]==0xcc && s[3]==0xf3 &&
		s[4]==0x85 && s[5]==0xeb && s[6]==0xc8 && s[7]==0xa0 &&
		s[8]==0xbf && s[9]==0xcc && s[10]==0x2a && s[11]==0x3c) {

	    /* Assign the hexadecimal value of long double type. */
	    s[0]=0x43; s[1]=0x51; s[2]=0xcc; s[3]=0xf3;
	    s[4]=0x85; s[5]=0xeb; s[6]=0xc8; s[7]=0xa0;
	    s[8]=0xbf; s[9]=0xcc; s[10]=0x2a; s[11]=0x3c;
	    s[12]=0x3d; s[13]=0x85; s[14]=0x56; s[15]=0x20;

	    memcpy(&ld, s, 16);

	    ll = (long)ld;
	    memcpy(s2, &ll, 8);

	    /* The library's algorithm converts it to 0x 00 47 33 ce 17 af 22 82
	     * and gets wrong value 20041683600089730 on the IBM Power6 Linux.
	     * But the IBM Power6 Linux converts it to 0x00 47 33 ce 17 af 22 7f
	     * and gets the correct value 20041683600089727.  It uses some special
	     * algorithm.  We're going to define the macro and skip the test until
	     * we can figure out how they do it. */
	    if(s2[0]==0x00 && s2[1]==0x47 && s2[2]==0x33 && s2[3]==0xce &&
		    s2[4]==0x17 && s2[5]==0xaf && s2[6]==0x22 && s2[7]==0x7f)
		ret = 0;

	    ull = (unsigned long)ld;
	    memcpy(s2, &ull, 8);

	    /* The unsigned long is the same as signed long. */
	    if(s2[0]==0x00 && s2[1]==0x47 && s2[2]==0x33 && s2[3]==0xce &&
		    s2[4]==0x17 && s2[5]==0xaf && s2[6]==0x22 && s2[7]==0x7f)
		ret = 0;
	}
    }

done:
    exit(ret);
}

#endif

#ifdef H5_LONG_TO_LDOUBLE_SPECIAL_TEST

int main(void)
{
    long double         ld;
    long                ll;
    unsigned long       ull;
    unsigned char       s[16];
    int                 flag=0, ret=1;

    /*Determine if long double has 16 byte in size, 11 bit exponent, and
     *the bias is 0x3ff */
    if(sizeof(long double) == 16) {
	ld = 1.0L;
	memcpy(s, &ld, 16);
	if(s[0]==0x3f && s[1]==0xf0 && s[2]==0x00 && s[3]==0x00 &&
		s[4]==0x00 && s[5]==0x00 && s[6]==0x00 && s[7]==0x00)
	    flag = 1;
    }

    if(flag==1 && sizeof(long)==8) {
	ll = 0x003fffffffffffffL;
	ld = (long double)ll;
	memcpy(s, &ld, 16);
	/* The library converts the value to 0x434fffffffffffff8000000000000000.
	 * In decimal it is 18014398509481982.000000, one value short of the original.
	 * The IBM Power6 Linux converts it to 0x4350000000000000bff0000000000000.
	 * The value is correct in decimal. It uses some special
	 * algorithm.  We're going to define the macro and skip the test until
	 * we can figure out how they do it. */
	if(s[0]==0x43 && s[1]==0x50 && s[2]==0x00 && s[3]==0x00 &&
		s[4]==0x00 && s[5]==0x00 && s[6]==0x00 && s[7]==0x00 &&
		s[8]==0xbf && s[9]==0xf0 && s[10]==0x00 && s[11]==0x00 &&
		s[12]==0x00 && s[13]==0x00 && s[14]==0x00 && s[15]==0x00)
	    ret = 0;
    }
    if(flag==1 && sizeof(unsigned long)==8) {
	ull = 0xffffffffffffffffUL;
	ld = (long double)ull;
	memcpy(s, &ld, 16);
	/* Use a different value from signed long to test. The problem is the same
	 * for both long and unsigned long. The value is 18446744073709551615.
	 * The library converts the value to 0x43effffffffffffffe000000000000000.
	 * In decimal it's 18446744073709548544.000000, very different from the original.
	 * The IBM Power6 Linux converts it to 0x43f0000000000000bff0000000000000.
	 * The value is correct in decimal. It uses some special
	 * algorithm.  We're going to define the macro and skip the test until
	 * we can figure out how they do it. */
	if(s[0]==0x43 && s[1]==0xf0 && s[2]==0x00 && s[3]==0x00 &&
		s[4]==0x00 && s[5]==0x00 && s[6]==0x00 && s[7]==0x00 &&
		s[8]==0xbf && s[9]==0xf0 && s[10]==0x00 && s[11]==0x00 &&
		s[12]==0x00 && s[13]==0x00 && s[14]==0x00 && s[15]==0x00)
	    ret = 0;
    }
done:
    exit(ret);
}

#endif

#ifdef H5_NO_ALIGNMENT_RESTRICTIONS_TEST

#include <stdlib.h>
#include <string.h>

typedef struct {
    size_t len;
    void *p;
} hvl_t;

#ifdef FC_DUMMY_MAIN
#ifndef FC_DUMMY_MAIN_EQ_F77
#  ifdef __cplusplus
extern "C"
#  endif
int FC_DUMMY_MAIN()
{ return 1;}
#endif
#endif
int
main ()
{

    char *chp = "beefs";
    char **chpp = malloc (2 * sizeof (char *));
    char **chpp2;
    hvl_t vl = { 12345, (void *) chp };
    hvl_t *vlp;
    hvl_t *vlp2;

    memcpy ((void *) ((char *) chpp + 1), &chp, sizeof (char *));
    chpp2 = (char **) ((char *) chpp + 1);
    if (strcmp (*chpp2, chp)) {
        free (chpp);
        return 1;
    }
    free (chpp);

    vlp = malloc (2 * sizeof (hvl_t));
    memcpy ((void *) ((char *) vlp + 1), &vl, sizeof (hvl_t));
    vlp2 = (hvl_t *) ((char *) vlp + 1);
    if (vlp2->len != vl.len || vlp2->p != vl.p) {
        free (vlp);
        return 1;
    }
    free (vlp);

  ;
  return 0;
}

#endif