fis-gtm/sr_port/op_fnzbitxor.c

68 lines
1.9 KiB
C

/****************************************************************
* *
* Copyright 2001, 2009 Fidelity Information Services, Inc *
* *
* This source code contains the intellectual property *
* of its copyright holder(s), and is made available *
* under a license. If you do not know the terms of *
* the license, please stop and do not read further. *
* *
****************************************************************/
#include "mdef.h"
#include "stringpool.h"
#include "op.h"
GBLREF spdesc stringpool;
static const unsigned char mask[8]={0xFF,0xFE,0xFC,0xF8,0xF0,0xE0,0xC0,0x80};
void op_fnzbitxor(mval *dst, mval *bitstr1, mval *bitstr2)
{
int n, str_len1, str_len2, new_str_len;
unsigned char *byte_1, *byte_n;
unsigned char *byte1_1, *byte1_n, byte1_len;
unsigned char *byte2_1, *byte2_n, byte2_len;
error_def(ERR_INVBITSTR);
MV_FORCE_STR(bitstr1);
MV_FORCE_STR(bitstr2);
if (!bitstr1->str.len || !bitstr2->str.len)
rts_error(VARLSTCNT(1) ERR_INVBITSTR);
byte1_len = *(unsigned char *)bitstr1->str.addr;
str_len1 = (bitstr1->str.len - 1) * 8;
if (7 < byte1_len)
rts_error(VARLSTCNT(1) ERR_INVBITSTR);
byte2_len = *(unsigned char *)bitstr2->str.addr;
str_len2 = (bitstr2->str.len -1) * 8;
if (7 < byte2_len)
rts_error(VARLSTCNT(1) ERR_INVBITSTR);
if (str_len1 - byte1_len > str_len2 - byte2_len)
new_str_len = str_len2 - byte2_len;
else
new_str_len = str_len1 - byte1_len;
n = (new_str_len + 7)/8 ;
ENSURE_STP_FREE_SPACE(n + 1);
byte_1 = (unsigned char *)stringpool.free;
*byte_1 = n * 8 - new_str_len;
byte1_1 = (unsigned char *)bitstr1->str.addr;
byte2_1 = (unsigned char *)bitstr2->str.addr;
for(byte_n = byte_1 + 1, byte1_n = byte1_1 + 1, byte2_n = byte2_1 + 1 ;
byte_n <= (byte_1 + n); byte_n++, byte1_n++, byte2_n++)
{
*byte_n = *byte1_n ^ *byte2_n;
}
*--byte_n &= mask[*byte_1];
dst->mvtype = MV_STR;
dst->str.addr = (char *)stringpool.free;
dst->str.len = n + 1;
stringpool.free += n + 1;
}