コード例 #1
0
ファイル: mi_dbug.c プロジェクト: OPSF/uClinux
void _mi_print_key(FILE *stream, register MI_KEYSEG *keyseg,
		   const uchar *key, uint length)
{
  int flag;
  short int s_1;
  long	int l_1;
  float f_1;
  double d_1;
  const uchar *end;
  const uchar *key_end=key+length;

  VOID(fputs("Key: \"",stream));
  flag=0;
  for (; keyseg->type && key < key_end ;keyseg++)
  {
    if (flag++)
      VOID(putc('-',stream));
    end= key+ keyseg->length;
    if (keyseg->flag & HA_NULL_PART)
    {
      if (!*key)
      {
	fprintf(stream,"NULL");
	continue;
      }
      key++;
    }

    switch (keyseg->type) {
    case HA_KEYTYPE_BINARY:
      if (!(keyseg->flag & HA_SPACE_PACK) && keyseg->length == 1)
      {						/* packed binary digit */
	VOID(fprintf(stream,"%d",(uint) *key++));
	break;
      }
      /* fall through */
    case HA_KEYTYPE_TEXT:
    case HA_KEYTYPE_NUM:
      if (keyseg->flag & HA_SPACE_PACK)
      {
	VOID(fprintf(stream,"%.*s",(int) *key,key+1));
	key+= (int) *key+1;
      }
      else
      {
	VOID(fprintf(stream,"%.*s",(int) keyseg->length,key));
	key=end;
      }
      break;
    case HA_KEYTYPE_INT8:
      VOID(fprintf(stream,"%d",(int) *((signed char*) key)));
      key=end;
      break;
    case HA_KEYTYPE_SHORT_INT:
      s_1= mi_sint2korr(key);
      VOID(fprintf(stream,"%d",(int) s_1));
      key=end;
      break;
    case HA_KEYTYPE_USHORT_INT:
      {
	ushort u_1;
	u_1= mi_uint2korr(key);
	VOID(fprintf(stream,"%u",(uint) u_1));
	key=end;
	break;
      }
    case HA_KEYTYPE_LONG_INT:
      l_1=mi_sint4korr(key);
      VOID(fprintf(stream,"%ld",l_1));
      key=end;
      break;
    case HA_KEYTYPE_ULONG_INT:
      l_1=mi_sint4korr(key);
      VOID(fprintf(stream,"%lu",(ulong) l_1));
      key=end;
      break;
    case HA_KEYTYPE_INT24:
      VOID(fprintf(stream,"%ld",(long) mi_sint3korr(key)));
      key=end;
      break;
    case HA_KEYTYPE_UINT24:
      VOID(fprintf(stream,"%lu",(ulong) mi_uint3korr(key)));
      key=end;
      break;
    case HA_KEYTYPE_FLOAT:
      mi_float4get(f_1,key);
      VOID(fprintf(stream,"%g",(double) f_1));
      key=end;
      break;
    case HA_KEYTYPE_DOUBLE:
      mi_float8get(d_1,key);
      VOID(fprintf(stream,"%g",d_1));
      key=end;
      break;
#ifdef HAVE_LONG_LONG
    case HA_KEYTYPE_LONGLONG:
    {
      char buff[21];
      longlong2str(mi_sint8korr(key),buff,-10);
      VOID(fprintf(stream,"%s",buff));
      key=end;
      break;
    }
    case HA_KEYTYPE_ULONGLONG:
    {
      char buff[21];
      longlong2str(mi_sint8korr(key),buff,10);
      VOID(fprintf(stream,"%s",buff));
      key=end;
      break;
    }
#endif
    case HA_KEYTYPE_VARTEXT:			/* VARCHAR and TEXT */
    case HA_KEYTYPE_VARBINARY:			/* VARBINARY and BLOB */
    {
      uint tmp_length;
      get_key_length(tmp_length,key);
      VOID(fprintf(stream,"%.*s",(int) tmp_length,key));
      key+=tmp_length;
      break;
    }
    default: break;			/* This never happens */
    }
  }
  VOID(fputs("\"\n",stream));
  return;
} /* print_key */
コード例 #2
0
ファイル: mi_dbug.c プロジェクト: AllenWeb/mariadb
void _mi_print_key(FILE *stream, register HA_KEYSEG *keyseg,
		   const uchar *key, uint length)
{
  int flag;
  short int s_1;
  long	int l_1;
  float f_1;
  double d_1;
  const uchar *end;
  const uchar *key_end=key+length;

  (void) fputs("Key: \"",stream);
  flag=0;
  for (; keyseg->type && key < key_end ;keyseg++)
  {
    if (flag++)
      (void) putc('-',stream);
    end= key+ keyseg->length;
    if (keyseg->flag & HA_NULL_PART)
    {
      /* A NULL value is encoded by a 1-byte flag. Zero means NULL. */
      if (! *(key++))
      {
	fprintf(stream,"NULL");
	continue;
      }
      end++;
    }

    switch (keyseg->type) {
    case HA_KEYTYPE_BINARY:
      if (!(keyseg->flag & HA_SPACE_PACK) && keyseg->length == 1)
      {						/* packed binary digit */
	(void) fprintf(stream,"%d",(uint) *key++);
	break;
      }
      /* fall through */
    case HA_KEYTYPE_TEXT:
    case HA_KEYTYPE_NUM:
      if (keyseg->flag & HA_SPACE_PACK)
      {
	(void) fprintf(stream,"%.*s",(int) *key,key+1);
	key+= (int) *key+1;
      }
      else
      {
	(void) fprintf(stream,"%.*s",(int) keyseg->length,key);
	key=end;
      }
      break;
    case HA_KEYTYPE_INT8:
      (void) fprintf(stream,"%d",(int) *((signed char*) key));
      key=end;
      break;
    case HA_KEYTYPE_SHORT_INT:
      s_1= mi_sint2korr(key);
      (void) fprintf(stream,"%d",(int) s_1);
      key=end;
      break;
    case HA_KEYTYPE_USHORT_INT:
      {
	ushort u_1;
	u_1= mi_uint2korr(key);
	(void) fprintf(stream,"%u",(uint) u_1);
	key=end;
	break;
      }
    case HA_KEYTYPE_LONG_INT:
      l_1=mi_sint4korr(key);
      (void) fprintf(stream,"%ld",l_1);
      key=end;
      break;
    case HA_KEYTYPE_ULONG_INT:
      l_1=mi_uint4korr(key);
      (void) fprintf(stream,"%lu",(ulong) l_1);
      key=end;
      break;
    case HA_KEYTYPE_INT24:
      (void) fprintf(stream,"%ld",(long) mi_sint3korr(key));
      key=end;
      break;
    case HA_KEYTYPE_UINT24:
      (void) fprintf(stream,"%lu",(ulong) mi_uint3korr(key));
      key=end;
      break;
    case HA_KEYTYPE_FLOAT:
      mi_float4get(f_1,key);
      (void) fprintf(stream,"%g",(double) f_1);
      key=end;
      break;
    case HA_KEYTYPE_DOUBLE:
      mi_float8get(d_1,key);
      (void) fprintf(stream,"%g",d_1);
      key=end;
      break;
#ifdef HAVE_LONG_LONG
    case HA_KEYTYPE_LONGLONG:
    {
      char buff[21];
      longlong10_to_str(mi_sint8korr(key),buff,-10);
      (void) fprintf(stream,"%s",buff);
      key=end;
      break;
    }
    case HA_KEYTYPE_ULONGLONG:
    {
      char buff[21];
      longlong10_to_str(mi_sint8korr(key),buff,10);
      (void) fprintf(stream,"%s",buff);
      key=end;
      break;
    }
#endif
    case HA_KEYTYPE_BIT:
    {
      uint i;
      fputs("0x",stream);
      for (i=0 ; i < keyseg->length ; i++)
        fprintf(stream, "%02x", (uint) *key++);
      key= end;
      break;
    }
    case HA_KEYTYPE_VARTEXT1:                   /* VARCHAR and TEXT */
    case HA_KEYTYPE_VARTEXT2:                   /* VARCHAR and TEXT */
    case HA_KEYTYPE_VARBINARY1:                 /* VARBINARY and BLOB */
    case HA_KEYTYPE_VARBINARY2:                 /* VARBINARY and BLOB */
    {
      uint tmp_length;
      get_key_length(tmp_length,key);
      /*
	The following command sometimes gives a warning from valgrind.
	Not yet sure if the bug is in valgrind, glibc or mysqld
      */
      (void) fprintf(stream,"%.*s",(int) tmp_length,key);
      key+=tmp_length;
      break;
    }
    default: break;			/* This never happens */
    }
  }
  (void) fputs("\"\n",stream);
  return;
} /* print_key */
コード例 #3
0
ファイル: dec_util.cpp プロジェクト: alheio/libslave
int bin2dec(const char *from, decimal_t *to, int precision, int scale)
{
    int error=E_DEC_OK, intg=precision-scale,
            intg0=intg/DIG_PER_DEC1, frac0=scale/DIG_PER_DEC1,
            intg0x=intg-intg0*DIG_PER_DEC1, frac0x=scale-frac0*DIG_PER_DEC1,
            intg1=intg0+(intg0x>0), frac1=frac0+(frac0x>0);
    dec1 *buf=to->buf, mask=(*from & 0x80) ? 0 : -1;
    const char *stop;
    char *d_copy;
    int bin_size= decimal_bin_size(precision, scale);

    //sanity(to);
    d_copy= (char*) my_alloca(bin_size);
    memcpy(d_copy, from, bin_size);
    d_copy[0]^= 0x80;
    from= d_copy;

    FIX_INTG_FRAC_ERROR(to->len, intg1, frac1, error);
    if (unlikely(error))
    {
        if (intg1 < intg0+(intg0x>0))
        {
            from+=dig2bytes[intg0x]+sizeof(dec1)*(intg0-intg1);
            frac0=frac0x=intg0x=0;
            intg0=intg1;
        }
        else
        {
            frac0x=0;
            frac0=frac1;
        }
    }

    to->sign=(mask != 0);
    to->intg=intg0*DIG_PER_DEC1+intg0x;
    to->frac=frac0*DIG_PER_DEC1+frac0x;

    if (intg0x)
    {
        int i=dig2bytes[intg0x];
        dec1 UNINIT_VAR(x);
        switch (i)
        {
            case 1: x=mi_sint1korr(from); break;
            case 2: x=mi_sint2korr(from); break;
            case 3: x=mi_sint3korr(from); break;
            case 4: x=mi_sint4korr(from); break;
            default: DBUG_ASSERT(0);
        }
        from+=i;
        *buf=x ^ mask;
        if (((ulonglong)*buf) >= (ulonglong) powers10[intg0x+1])
            goto err;
        if (buf > to->buf || *buf != 0)
            buf++;
        else
            to->intg-=intg0x;
    }
    for (stop=from+intg0*sizeof(dec1); from < stop; from+=sizeof(dec1))
    {
        DBUG_ASSERT(sizeof(dec1) == 4);
        *buf=mi_sint4korr(from) ^ mask;
        if (((uint32)*buf) > DIG_MAX)
            goto err;
        if (buf > to->buf || *buf != 0)
            buf++;
        else
            to->intg-=DIG_PER_DEC1;
    }
    DBUG_ASSERT(to->intg >=0);
    for (stop=from+frac0*sizeof(dec1); from < stop; from+=sizeof(dec1))
    {
        DBUG_ASSERT(sizeof(dec1) == 4);
        *buf=mi_sint4korr(from) ^ mask;
        if (((uint32)*buf) > DIG_MAX)
            goto err;
        buf++;
    }
    if (frac0x)
    {
        int i=dig2bytes[frac0x];
        dec1 UNINIT_VAR(x);
        switch (i)
        {
            case 1: x=mi_sint1korr(from); break;
            case 2: x=mi_sint2korr(from); break;
            case 3: x=mi_sint3korr(from); break;
            case 4: x=mi_sint4korr(from); break;
            default: DBUG_ASSERT(0);
        }
        *buf=(x ^ mask) * powers10[DIG_PER_DEC1 - frac0x];
        if (((uint32)*buf) > DIG_MAX)
            goto err;
        buf++;
    }
    my_afree(d_copy);

    if (to->intg == 0 && to->frac == 0)
        decimal_make_zero(to);
    return error;

err:
    my_afree(d_copy);
    decimal_make_zero(to);
    return(E_DEC_BAD_NUM);
}
コード例 #4
0
ファイル: my_handler.c プロジェクト: XEQT/SkyFireEMU
int ha_key_cmp(register HA_KEYSEG *keyseg, register uchar *a,
	       register uchar *b, uint key_length, uint nextflag,
	       uint *diff_pos)
{
  int flag;
  int16 s_1,s_2;
  int32 l_1,l_2;
  uint32 u_1,u_2;
  float f_1,f_2;
  double d_1,d_2;
  uint next_key_length;
  uchar *orig_b= b;

  *diff_pos=0;
  for ( ; (int) key_length >0 ; key_length=next_key_length, keyseg++)
  {
    uchar *end;
    uint piks=! (keyseg->flag & HA_NO_SORT);
    (*diff_pos)++;
    diff_pos[1]= (uint)(b - orig_b);

    /* Handle NULL part */
    if (keyseg->null_bit)
    {
      key_length--;
      if (*a != *b && piks)
      {
        flag = (int) *a - (int) *b;
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      }
      b++;
      if (!*a++)                                /* If key was NULL */
      {
        if (nextflag == (SEARCH_FIND | SEARCH_UPDATE))
          nextflag=SEARCH_SAME;                 /* Allow duplicate keys */
  	else if (nextflag & SEARCH_NULL_ARE_NOT_EQUAL)
	{
	  /*
	    This is only used from mi_check() to calculate cardinality.
	    It can't be used when searching for a key as this would cause
	    compare of (a,b) and (b,a) to return the same value.
	  */
	  return -1;
	}
        next_key_length=key_length;
        continue;                               /* To next key part */
      }
    }
    end= a+ min(keyseg->length,key_length);
    next_key_length=key_length-keyseg->length;

    switch ((enum ha_base_keytype) keyseg->type) {
    case HA_KEYTYPE_TEXT:                       /* Ascii; Key is converted */
      if (keyseg->flag & HA_SPACE_PACK)
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
            (flag=ha_compare_text(keyseg->charset,a,a_length,b,b_length,
				  (my_bool) ((nextflag & SEARCH_PREFIX) &&
					     next_key_length <= 0),
				  (my_bool)!(nextflag & SEARCH_PREFIX))))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=a_length;
        b+=b_length;
        break;
      }
      else
      {
	uint length=(uint) (end-a), a_length=length, b_length=length;
        if (piks &&
            (flag= ha_compare_text(keyseg->charset, a, a_length, b, b_length,
				   (my_bool) ((nextflag & SEARCH_PREFIX) &&
					      next_key_length <= 0),
				   (my_bool)!(nextflag & SEARCH_PREFIX))))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a=end;
        b+=length;
      }
      break;
    case HA_KEYTYPE_BINARY:
    case HA_KEYTYPE_BIT:
      if (keyseg->flag & HA_SPACE_PACK)
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
	    (flag=compare_bin(a,a_length,b,b_length,
                              (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                         next_key_length <= 0),1)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=a_length;
        b+=b_length;
        break;
      }
      else
      {
        uint length=keyseg->length;
        if (piks &&
	    (flag=compare_bin(a,length,b,length,
                              (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                         next_key_length <= 0),0)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=length;
        b+=length;
      }
      break;
    case HA_KEYTYPE_VARTEXT1:
    case HA_KEYTYPE_VARTEXT2:
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
	    (flag= ha_compare_text(keyseg->charset,a,a_length,b,b_length,
                                   (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                              next_key_length <= 0),
				   (my_bool) ((nextflag & (SEARCH_FIND |
							   SEARCH_UPDATE)) ==
					      SEARCH_FIND &&
                                              ! (keyseg->flag &
                                                 HA_END_SPACE_ARE_EQUAL)))))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+= a_length;
        b+= b_length;
        break;
      }
      break;
    case HA_KEYTYPE_VARBINARY1:
    case HA_KEYTYPE_VARBINARY2:
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
	    (flag=compare_bin(a,a_length,b,b_length,
                              (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                         next_key_length <= 0), 0)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=a_length;
        b+=b_length;
      }
      break;
    case HA_KEYTYPE_INT8:
    {
      int i_1= (int) *((signed char*) a);
      int i_2= (int) *((signed char*) b);
      if (piks && (flag = CMP_NUM(i_1,i_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a= end;
      b++;
      break;
    }
    case HA_KEYTYPE_SHORT_INT:
      s_1= mi_sint2korr(a);
      s_2= mi_sint2korr(b);
      if (piks && (flag = CMP_NUM(s_1,s_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 2; /* sizeof(short int); */
      break;
    case HA_KEYTYPE_USHORT_INT:
      {
        uint16 us_1,us_2;
        us_1= mi_sint2korr(a);
        us_2= mi_sint2korr(b);
        if (piks && (flag = CMP_NUM(us_1,us_2)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a=  end;
        b+=2; /* sizeof(short int); */
        break;
      }
    case HA_KEYTYPE_LONG_INT:
      l_1= mi_sint4korr(a);
      l_2= mi_sint4korr(b);
      if (piks && (flag = CMP_NUM(l_1,l_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 4; /* sizeof(long int); */
      break;
    case HA_KEYTYPE_ULONG_INT:
      u_1= mi_sint4korr(a);
      u_2= mi_sint4korr(b);
      if (piks && (flag = CMP_NUM(u_1,u_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 4; /* sizeof(long int); */
      break;
    case HA_KEYTYPE_INT24:
      l_1=mi_sint3korr(a);
      l_2=mi_sint3korr(b);
      if (piks && (flag = CMP_NUM(l_1,l_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 3;
      break;
    case HA_KEYTYPE_UINT24:
      l_1=mi_uint3korr(a);
      l_2=mi_uint3korr(b);
      if (piks && (flag = CMP_NUM(l_1,l_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 3;
      break;
    case HA_KEYTYPE_FLOAT:
      mi_float4get(f_1,a);
      mi_float4get(f_2,b);
      /*
        The following may give a compiler warning about floating point
        comparison not being safe, but this is ok in this context as
        we are bascily doing sorting
      */
      if (piks && (flag = CMP_NUM(f_1,f_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 4; /* sizeof(float); */
      break;
    case HA_KEYTYPE_DOUBLE:
      mi_float8get(d_1,a);
      mi_float8get(d_2,b);
      /*
        The following may give a compiler warning about floating point
        comparison not being safe, but this is ok in this context as
        we are bascily doing sorting
      */
      if (piks && (flag = CMP_NUM(d_1,d_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 8;  /* sizeof(double); */
      break;
    case HA_KEYTYPE_NUM:                                /* Numeric key */
    {
      int swap_flag= 0;
      int alength,blength;

      if (keyseg->flag & HA_REVERSE_SORT)
      {
        swap_variables(uchar*, a, b);
        swap_flag=1;                            /* Remember swap of a & b */
        end= a+ (int) (end-b);
      }
      if (keyseg->flag & HA_SPACE_PACK)
      {
        alength= *a++; blength= *b++;
        end=a+alength;
        next_key_length=key_length-blength-1;
      }
      else
      {
        alength= (int) (end-a);
        blength=keyseg->length;
        /* remove pre space from keys */
        for ( ; alength && *a == ' ' ; a++, alength--) ;
        for ( ; blength && *b == ' ' ; b++, blength--) ;
      }
      if (piks)
      {
	if (*a == '-')
	{
	  if (*b != '-')
	    return -1;
	  a++; b++;
	  swap_variables(uchar*, a, b);
	  swap_variables(int, alength, blength);
	  swap_flag=1-swap_flag;
	  alength--; blength--;
	  end=a+alength;
	}
	else if (*b == '-')
	  return 1;
	while (alength && (*a == '+' || *a == '0'))
	{
	  a++; alength--;
	}
	while (blength && (*b == '+' || *b == '0'))
	{
	  b++; blength--;
	}
	if (alength != blength)
	  return (alength < blength) ? -1 : 1;
	while (a < end)
	  if (*a++ !=  *b++)
	    return ((int) a[-1] - (int) b[-1]);
      }
      else
      {
        b+=(end-a);
        a=end;
      }

      if (swap_flag)                            /* Restore pointers */
        swap_variables(uchar*, a, b);
      break;
    }
#ifdef HAVE_LONG_LONG
    case HA_KEYTYPE_LONGLONG:
    {
      longlong ll_a,ll_b;
      ll_a= mi_sint8korr(a);
      ll_b= mi_sint8korr(b);
      if (piks && (flag = CMP_NUM(ll_a,ll_b)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 8;
      break;
    }
    case HA_KEYTYPE_ULONGLONG:
    {
      ulonglong ll_a,ll_b;
      ll_a= mi_uint8korr(a);
      ll_b= mi_uint8korr(b);
      if (piks && (flag = CMP_NUM(ll_a,ll_b)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 8;
      break;
    }
#endif
    case HA_KEYTYPE_END:                        /* Ready */
      goto end;                                 /* diff_pos is incremented */
    }
  }
  (*diff_pos)++;
end:
  if (!(nextflag & SEARCH_FIND))
  {
    uint i;
    if (nextflag & (SEARCH_NO_FIND | SEARCH_LAST)) /* Find record after key */
      return (nextflag & (SEARCH_BIGGER | SEARCH_LAST)) ? -1 : 1;
    flag=0;
    for (i=keyseg->length ; i-- > 0 ; )
    {
      if (*a++ != *b++)
      {
        flag= FCMP(a[-1],b[-1]);
        break;
      }
    }
    if (nextflag & SEARCH_SAME)
      return (flag);                            /* read same */
    if (nextflag & SEARCH_BIGGER)
      return (flag <= 0 ? -1 : 1);              /* read next */
    return (flag < 0 ? -1 : 1);                 /* read previous */
  }
  return 0;
} /* ha_key_cmp */
コード例 #5
0
int ha_key_cmp(HA_KEYSEG *keyseg, const uchar *a,
               const uchar *b, uint key_length, uint32 nextflag,
	       uint *diff_pos)
{
  int flag;
  int16 s_1,s_2;
  int32 l_1,l_2;
  uint32 u_1,u_2;
  float f_1,f_2;
  double d_1,d_2;
  uint next_key_length;
  const uchar *orig_b= b;

  *diff_pos=0;
  for ( ; (int) key_length >0 ; key_length=next_key_length, keyseg++)
  {
    const uchar *end;
    uint piks=! (keyseg->flag & HA_NO_SORT);
    (*diff_pos)++;
    diff_pos[1]= (uint)(b - orig_b);

    /* Handle NULL part */
    if (keyseg->null_bit)
    {
      key_length--;
      if (*a != *b && piks)
      {
        flag = (int) *a - (int) *b;
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      }
      b++;
      if (!*a++)                                /* If key was NULL */
      {
        if ((nextflag & (SEARCH_FIND | SEARCH_UPDATE | SEARCH_INSERT |
                         SEARCH_NULL_ARE_EQUAL)) ==
            (SEARCH_FIND | SEARCH_UPDATE | SEARCH_INSERT))
        {
          /* Allow duplicate keys */
          nextflag= (nextflag & ~(SEARCH_FIND | SEARCH_UPDATE)) | SEARCH_SAME;
        }
  	else if (nextflag & SEARCH_NULL_ARE_NOT_EQUAL)
	{
	  /*
	    This is only used from mi_check() to calculate cardinality.
	    It can't be used when searching for a key as this would cause
	    compare of (a,b) and (b,a) to return the same value.
	  */
	  return -1;
	}
        next_key_length=key_length;
        continue;                               /* To next key part */
      }
    }
    end= a+ MY_MIN(keyseg->length,key_length);
    next_key_length=key_length-keyseg->length;

    switch ((enum ha_base_keytype) keyseg->type) {
    case HA_KEYTYPE_TEXT:                       /* Ascii; Key is converted */
      if (keyseg->flag & HA_SPACE_PACK)
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
            (flag=ha_compare_text(keyseg->charset,a,a_length,b,b_length,
				  (my_bool) ((nextflag & SEARCH_PREFIX) &&
					     next_key_length <= 0),
				  (my_bool)!(nextflag & SEARCH_PREFIX))))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=a_length;
        b+=b_length;
        break;
      }
      else
      {
	uint length=(uint) (end-a), a_length=length, b_length=length;
        if (piks &&
            (flag= ha_compare_text(keyseg->charset, a, a_length, b, b_length,
				   (my_bool) ((nextflag & SEARCH_PREFIX) &&
					      next_key_length <= 0),
				   (my_bool)!(nextflag & SEARCH_PREFIX))))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a=end;
        b+=length;
      }
      break;
    case HA_KEYTYPE_BINARY:
    case HA_KEYTYPE_BIT:
      if (keyseg->flag & HA_SPACE_PACK)
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
	    (flag=compare_bin(a,a_length,b,b_length,
                              (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                         next_key_length <= 0),1)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=a_length;
        b+=b_length;
        break;
      }
      else
      {
        uint length=keyseg->length;
        if (piks &&
	    (flag=compare_bin(a,length,b,length,
                              (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                         next_key_length <= 0),0)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=length;
        b+=length;
      }
      break;
    case HA_KEYTYPE_VARTEXT1:
    case HA_KEYTYPE_VARTEXT2:
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
	    (flag= ha_compare_text(keyseg->charset,a,a_length,b,b_length,
                                   (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                              next_key_length <= 0),
				   (my_bool) ((nextflag & (SEARCH_FIND |
							   SEARCH_UPDATE)) ==
					      SEARCH_FIND &&
                                              ! (keyseg->flag &
                                                 HA_END_SPACE_ARE_EQUAL)))))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+= a_length;
        b+= b_length;
        break;
      }
      break;
    case HA_KEYTYPE_VARBINARY1:
    case HA_KEYTYPE_VARBINARY2:
      {
        int a_length,b_length,pack_length;
        get_key_length(a_length,a);
        get_key_pack_length(b_length,pack_length,b);
        next_key_length=key_length-b_length-pack_length;

        if (piks &&
	    (flag=compare_bin(a,a_length,b,b_length,
                              (my_bool) ((nextflag & SEARCH_PREFIX) &&
                                         next_key_length <= 0), 0)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a+=a_length;
        b+=b_length;
      }
      break;
    case HA_KEYTYPE_INT8:
    {
      int i_1= (int) *((signed char*) a);
      int i_2= (int) *((signed char*) b);
      if (piks && (flag = CMP_NUM(i_1,i_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a= end;
      b++;
      break;
    }
    case HA_KEYTYPE_SHORT_INT:
      s_1= mi_sint2korr(a);
      s_2= mi_sint2korr(b);
      if (piks && (flag = CMP_NUM(s_1,s_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 2; /* sizeof(short int); */
      break;
    case HA_KEYTYPE_USHORT_INT:
      {
        uint16 us_1,us_2;
        us_1= mi_sint2korr(a);
        us_2= mi_sint2korr(b);
        if (piks && (flag = CMP_NUM(us_1,us_2)))
          return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
        a=  end;
        b+=2; /* sizeof(short int); */
        break;
      }
    case HA_KEYTYPE_LONG_INT:
      l_1= mi_sint4korr(a);
      l_2= mi_sint4korr(b);
      if (piks && (flag = CMP_NUM(l_1,l_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 4; /* sizeof(long int); */
      break;
    case HA_KEYTYPE_ULONG_INT:
      u_1= mi_sint4korr(a);
      u_2= mi_sint4korr(b);
      if (piks && (flag = CMP_NUM(u_1,u_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 4; /* sizeof(long int); */
      break;
    case HA_KEYTYPE_INT24:
      l_1=mi_sint3korr(a);
      l_2=mi_sint3korr(b);
      if (piks && (flag = CMP_NUM(l_1,l_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 3;
      break;
    case HA_KEYTYPE_UINT24:
      l_1=mi_uint3korr(a);
      l_2=mi_uint3korr(b);
      if (piks && (flag = CMP_NUM(l_1,l_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 3;
      break;
    case HA_KEYTYPE_FLOAT:
      mi_float4get(f_1,a);
      mi_float4get(f_2,b);
      /*
        The following may give a compiler warning about floating point
        comparison not being safe, but this is ok in this context as
        we are bascily doing sorting
      */
      if (piks && (flag = CMP_NUM(f_1,f_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 4; /* sizeof(float); */
      break;
    case HA_KEYTYPE_DOUBLE:
      mi_float8get(d_1,a);
      mi_float8get(d_2,b);
      /*
        The following may give a compiler warning about floating point
        comparison not being safe, but this is ok in this context as
        we are bascily doing sorting
      */
      if (piks && (flag = CMP_NUM(d_1,d_2)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 8;  /* sizeof(double); */
      break;
    case HA_KEYTYPE_NUM:                                /* Numeric key */
    {
      int swap_flag= 0;
      int alength,blength;

      if (keyseg->flag & HA_REVERSE_SORT)
      {
        swap_variables(const uchar*, a, b);
        swap_flag=1;                            /* Remember swap of a & b */
        end= a+ (int) (end-b);
      }
      if (keyseg->flag & HA_SPACE_PACK)
      {
        alength= *a++; blength= *b++;
        end=a+alength;
        next_key_length=key_length-blength-1;
      }
      else
      {
        alength= (int) (end-a);
        blength=keyseg->length;
        /* remove pre space from keys */
        for ( ; alength && *a == ' ' ; a++, alength--) ;
        for ( ; blength && *b == ' ' ; b++, blength--) ;
      }
      if (piks)
      {
	if (*a == '-')
	{
	  if (*b != '-')
	    return -1;
	  a++; b++;
	  swap_variables(const uchar*, a, b);
	  swap_variables(int, alength, blength);
	  swap_flag=1-swap_flag;
	  alength--; blength--;
	  end=a+alength;
	}
	else if (*b == '-')
	  return 1;
	while (alength && (*a == '+' || *a == '0'))
	{
	  a++; alength--;
	}
	while (blength && (*b == '+' || *b == '0'))
	{
	  b++; blength--;
	}
	if (alength != blength)
	  return (alength < blength) ? -1 : 1;
	while (a < end)
	  if (*a++ !=  *b++)
	    return ((int) a[-1] - (int) b[-1]);
      }
      else
      {
        b+=(end-a);
        a=end;
      }

      if (swap_flag)                            /* Restore pointers */
        swap_variables(const uchar*, a, b);
      break;
    }
#ifdef HAVE_LONG_LONG
    case HA_KEYTYPE_LONGLONG:
    {
      longlong ll_a,ll_b;
      ll_a= mi_sint8korr(a);
      ll_b= mi_sint8korr(b);
      if (piks && (flag = CMP_NUM(ll_a,ll_b)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 8;
      break;
    }
    case HA_KEYTYPE_ULONGLONG:
    {
      ulonglong ll_a,ll_b;
      ll_a= mi_uint8korr(a);
      ll_b= mi_uint8korr(b);
      if (piks && (flag = CMP_NUM(ll_a,ll_b)))
        return ((keyseg->flag & HA_REVERSE_SORT) ? -flag : flag);
      a=  end;
      b+= 8;
      break;
    }
#endif
    case HA_KEYTYPE_END:                        /* Ready */
      goto end;                                 /* diff_pos is incremented */
    }
  }
  (*diff_pos)++;
end:
  if (!(nextflag & SEARCH_FIND))
  {
    /*
      Compare rowid and possible transid
      This happens in the following case:
      - INSERT, UPDATE, DELETE when we have not unique keys or
        are using versioning
      - SEARCH_NEXT, SEARCH_PREVIOUS when we need to restart search

      The logic for comparing transid are as follows:
      Keys with have a transid have lowest bit in the rowidt. This means that
      if we are comparing a key with a transid with another key that doesn't
      have a tranid, we must reset the lowest bit for both keys.

      When we have transid, the keys are compared in transid order.
      A key without a transid is regared to be smaller than a key with
      a transid.
    */

    uint i;
    uchar key_mask, tmp_a, tmp_b;

    if (nextflag & (SEARCH_NO_FIND | SEARCH_LAST)) /* Find record after key */
      return (nextflag & (SEARCH_BIGGER | SEARCH_LAST)) ? -1 : 1;
    key_mask= (uchar) 255;

    if (!(nextflag & (SEARCH_USER_KEY_HAS_TRANSID |
                      SEARCH_PAGE_KEY_HAS_TRANSID)))
    {
      /*
        Neither key has a trid.  Only compare row id's and don't
        try to store rows in trid order
      */
      key_length= keyseg->length;
      nextflag&= ~SEARCH_INSERT;
    }
    else
    {
      /*
        Set key_mask so that we reset the last bit in the rowid before
        we compare it. This is needed as the lowest bit in the rowid is
        used to mark if the key has a transid or not.
      */
      key_mask= (uchar) 254;
      if (!test_all_bits(nextflag, (SEARCH_USER_KEY_HAS_TRANSID |
                                    SEARCH_PAGE_KEY_HAS_TRANSID)))
      {
        /*
          No transaction id for user key or for key on page 
          Ignore transid as at least one of the keys are visible for all
        */
        key_length= keyseg->length;
      }
      else
      {
        /*
          Both keys have trids. No need of special handling of incomplete
          trids below.
        */
        nextflag&= ~SEARCH_INSERT;
      }
    }
    DBUG_ASSERT(key_length > 0);

    for (i= key_length-1 ; (int) i-- > 0 ; )
    {
      if (*a++ != *b++)
      {
        flag= FCMP(a[-1],b[-1]);
        goto found;
      }
    }
    tmp_a= *a & key_mask;
    tmp_b= *b & key_mask;
    flag= FCMP(tmp_a, tmp_b);

    if (flag == 0 && (nextflag & SEARCH_INSERT))
    {
      /*
        Ensure that on insert we get rows stored in trid order.
        If one of the parts doesn't have a trid, this should be regarded
        as smaller than the other
      */
        return (nextflag & SEARCH_USER_KEY_HAS_TRANSID) ? -1 : 1;
    }
found:
    if (nextflag & SEARCH_SAME)
      return (flag);                            /* read same */
    if (nextflag & SEARCH_BIGGER)
      return (flag <= 0 ? -1 : 1);              /* read next */
    return (flag < 0 ? -1 : 1);                 /* read previous */
  }
  return 0;
} /* ha_key_cmp */