do/vecset


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void
do_vecset(mstr,TARG)
STR *mstr;
STR *TARG;
{
    struct lstring *lstr = (struct lstring*)TARG;
    register int offset;
    register int size;
    register unsigned char *s = (unsigned char*)mstr->str_ptr;
    register unsigned long lval = U_L(str_gnum(TARG));
    int mask;

    mstr->str_rare = 0;
    TARG->str_magic = Nullstr;
    offset = lstr->lstr_offset;
    size = lstr->lstr_len;
    if (size < 8) {
	mask = (1 << size) - 1;
	size = offset & 7;
	lval &= mask;
	offset >>= 3;
	s[offset] &= ~(mask << size);
	s[offset] |= lval << size;
    }
    else {
	if (size == 8)
	    s[offset] = lval & 255;
	else if (size == 16) {
	    s[offset] = (lval >> 8) & 255;
	    s[offset+1] = lval & 255;
	}
	else if (size == 32) {
	    s[offset] = (lval >> 24) & 255;
	    s[offset+1] = (lval >> 16) & 255;
	    s[offset+2] = (lval >> 8) & 255;
	    s[offset+3] = lval & 255;
	}
    }
}