dos_compilers/Zortech C++ v206/TOOLS/SOURCE/BCD.CPP

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2024-07-02 16:30:38 +02:00
#include <bcd.hpp>
#include <string.h>
// The following are assembler functions in BCDLOW.ASM
// they have C linkage
extern "C" {
int bcd_add(int, unsigned char *, unsigned char *);
int bcd_sub(int, unsigned char *, unsigned char *);
int bcd_inc(int, unsigned char *);
int bcd_dec(int, unsigned char *);
int bcd_mul(int, unsigned char *, int);
int bcd_mul10(int, unsigned char *);
int bcd_div10(int, unsigned char *);
int memrcmp(void*, void*, unsigned);
int memtest(void*, unsigned);
}
typedef void (* PFC)(int, char*);
extern void default_error(int,char*);
static PFC bcd_handler = default_error;
void bcd::decode(char *b)
{
int i;
unsigned char *p = body;
if (sign)
sprintf(b++,"-"); // sign if negative
char *q = b;
for (p += nbytes-1, i = nbytes; i--; --p, q += 2)
sprintf(q,"%d%d", *p >> 4, *p & 0xf);
// print digits
q = b;
while (*q == '0') // strip leading zeros
++q;
if (!*q)
--q;
if (q > b) {
*b = '\0';
strcat(b,q);
}
}
int bcd::test()
{
if (memtest(body,nbytes))
return (sign? -1: 1);
return 0;
}
void bcd::ltobcd(long n)
{
int digit;
unsigned char *d = body;
memset(d,'\0',nbytes); // make sure nothing there
if (n < 0) {
sign = '\xff'; // fill in sign
n = -n;
} else
sign = '\0';
while (n) {
digit = n % 10;
n /= 10;
*d = digit; // fill in low nibble
if (!n)
break; // nothing left to fill in
digit = n % 10;
n /= 10;
*d += digit << 4; // then high one
++d;
}
}
int bcd_pow10(int nb, unsigned char * a, int n)
{
int i, of = 0;
unsigned char *p;
if (!n)
return 0;
if (n & 1) { // if odd power * by 10
of = bcd_mul10(nb,a);
--n;
if (!n) // no more
return 0;
}
n /= 2;
for (i = n, p = a+nb-1; i--;)
if (*p--)
of = 1; // check if anything in top n bytes
memmove(a+n,a,nb-n);
memset(a,'\0',n);
return of;
}
int bcd::lmul(bcd& s)
{
unsigned char acc[80], buf[80], *b = s.body;
int of = 0, i,j, digit;
memset(acc,'\0',nbytes);
for (i = nbytes; i--; ++b) {
if (!memtest(b,i))
break; // rest of multiplier zero
digit = *b & 0xf;
if (digit) {
memmove(buf,body,nbytes);
of += bcd_mul(nbytes,buf,digit); // mul by low nibble digit
of += bcd_add(nbytes,acc,buf); // add to accumulator
}
of += bcd_mul10(nbytes,body); // * 10 for next digit
digit = *b >> 4;
if (digit) {
memmove(buf,body,nbytes);
of += bcd_mul(nbytes,buf,digit); // mul by high nibble
of += bcd_add(nbytes,acc,buf); // add to accumulator
}
if (i) // don't overflow on limit
of += bcd_mul10(nbytes,body); // * 10 for next digit
}
memmove(body,acc,nbytes);
return of;
}
int bcd::ldiv(bcd& b)
{
unsigned char *p, quot[80], test[80], hold[80];
int n, m;
for (m = nbytes*2, p = body+(nbytes-1); !*p && m; --p, m -= 2) ;
if (!m) return 0; // dividend 0 - nothing to do
if (!(*p & 0xf0))
--m; // gets number of significant digits in dividend
for (n = nbytes*2, p = b.body+(nbytes-1); !*p && n; --p, n -= 2) ;
if (!n) {
status = -1; // dividing by zero
return -1;
}
if (!(*p & 0xf0))
--n; // gets significant digits in divisor
if (m < n) {
memmove(b.body,body,nbytes); // won't go, fill in remainder
memset(body,'\0',nbytes); // and zero quotient
return 0;
}
memset(quot,'\0',nbytes); // ready quotient
n = m-n; // get iterations required
bcd_pow10(nbytes,b.body,n++); // and prepare to subtract
for (; n--;) { // iterate
memmove(test,b.body,nbytes); // 1 * divisor
memset(hold,'\0',nbytes); // 0 * divisor
for (; memrcmp(test,body,nbytes) <= 0;) {
bcd_inc(nbytes,quot); // will subtract, adjust quotient
memmove(hold,test,nbytes); // keep a copy
if (bcd_add(nbytes,test,b.body))
break; // overflowed
}
// test is now too big - hold has previous value
bcd_sub(nbytes,body,hold); // subtract from dividend
bcd_div10(nbytes,b.body); // divisor/10
if (n)
bcd_mul10(nbytes,quot); // quotient*10 if any more
}
memmove(b.body,body,nbytes); // report remainder
memmove(body,quot,nbytes); // and quotient
return 0;
}
int bcd::signed_add(bcd& b)
// *this must always be >= b in magnitude
{
int of = 0;
if (sign) {
if (b.sign)
of = bcd_add(nbytes,body,b.body);
else
of = bcd_sub(nbytes,body,b.body);
sign = 0xff;
} else {
if (b.sign)
of = bcd_sub(nbytes,body,b.body);
else
of = bcd_add(nbytes,body,b.body);
sign = 0;
}
return of;
}
void bcd::atobcd(char *s)
{
int i, t;
char *q;
unsigned char *p = body;
t = strlen(s);
if (!t) {
status = sign = 0;
return;
}
if (*s == '-') {
q = s+1;
sign = '\xff';
} else {
q = s;
sign = '\0';
}
s += t-1; // start with least significant
for (i = nbytes*2; s >= q && i;) {
*p = *s-'0'; // low nibble
--s;
--i;
if (!(s >= q && i))
break; // no more string or no room
t = (*s-'0') << 4;
*p += t; // add high nibble
++p;
--s;
--i;
}
if (s >= q) // some string left report overflow
status = 1;
}
bcd::bcd()
{
nbytes = 12;
body = new unsigned char[nbytes];
if (!body) {
bcd_handler(ENOMEM,"bcd - not enough memory");
return;
}
sign = '\0';
memset(body,'\0',nbytes);
}
bcd::bcd(long n, int nd)
{
nbytes = ((nd+1) & ~1)/2;
body = new unsigned char[nbytes];
if (!body) {
bcd_handler(ENOMEM,"bcd - not enough memory");
return;
}
sign = n < 0L? '\xff': '\0';
status = 0;
if (n)
ltobcd(n);
else
memset(body,'\0',nbytes);
}
bcd::bcd(bcd& a)
{
body = new unsigned char[a.nbytes];
if (!body) {
bcd_handler(ENOMEM,"bcd - not enough memory");
return;
}
nbytes = a.nbytes;
memmove(body,a.body,nbytes);
sign = a.sign; status = a.status;
}
bcd::bcd(char *ds, int nd)
{
nbytes = ((nd+1) & ~1)/2;
body = new unsigned char[nbytes];
if (!body) {
bcd_handler(ENOMEM,"bcd - not enough memory");
return;
}
memset(body,'\0',nbytes);
atobcd(ds);
}
bcd& bcd::operator=(bcd& a)
{
if (this == &a)
return *this;
delete body;
body = new unsigned char[a.nbytes];
if (!body) {
bcd_handler(ENOMEM,"bcd - not enough memory");
return *this;
}
memmove(body,a.body,a.nbytes);
nbytes = a.nbytes;
sign = a.sign;
status = a.status;
return *this;
}
bcd& bcd::operator=(long n)
{
sign = n < 0L? '\xff': '\0';
status = 0;
ltobcd(n);
return *this;
}
bcd& bcd::operator=(char *s)
{
memset(body,'\0',nbytes);
atobcd(s);
return *this;
}
bcd bcd::operator+(bcd& a)
{
bcd loc(*this);
if (memrcmp(loc.body,a.body,nbytes) >= 0)
loc.status = loc.signed_add(a);
else {
loc = a;
loc.status = loc.signed_add(*this);
}
return loc;
}
bcd bcd::operator+(long n)
{
bcd lv(n, 2*this->nbytes); // must work with copies
bcd loc(*this);
if (memrcmp(loc.body,lv.body,nbytes) >= 0) {
loc.status = loc.signed_add(lv);
return loc;
} else {
lv.status = lv.signed_add(loc);
return lv;
}
}
bcd bcd::operator-(bcd& a)
{
bcd loc(*this);
a.sign = !a.sign;
if (memrcmp(loc.body,a.body,nbytes) >= 0) {
loc.status = loc.signed_add(a);
} else {
loc = a;
loc.status = loc.signed_add(*this);
}
a.sign = !a.sign;
return loc;
}
bcd bcd::operator-(long n)
{
bcd lv(n, 2*this->nbytes); // must work with copies
bcd loc(*this);
lv.sign = !lv.sign;
if (memrcmp(loc.body,lv.body,nbytes) >= 0) {
loc.status = loc.signed_add(lv);
return loc;
} else {
lv.status = lv.signed_add(loc);
return lv;
}
}
bcd& bcd::operator++()
{
if (!test())
sign = 0;
if (sign)
status = bcd_dec(nbytes,body);
else
status = bcd_inc(nbytes,body);
return *this;
}
bcd& bcd::operator--()
{
if (!test())
sign = 1;
if (sign)
status = bcd_inc(nbytes,body);
else
status = bcd_dec(nbytes,body);
return *this;
}
bcd bcd::operator*(bcd& a)
{
bcd loc(*this);
loc.sign = loc.sign != a.sign? '\xff': '\0';
loc.status = loc.lmul(a);
return loc;
}
bcd bcd::operator*(long n)
{
bcd lv(n, 2*this->nbytes);
bcd loc(*this);
loc.sign = loc.sign != lv.sign? '\xff': '\0';
loc.status = loc.lmul(lv);
return loc;
}
bcd bcd::operator/(bcd a) // parameter is a copy
{
bcd loc(*this);
loc.sign = loc.sign != a.sign? '\xff': '\0';
loc.status = loc.ldiv(a);
return loc; // gets quotient
}
bcd bcd::operator%(bcd a) // parameter is a copy
{
bcd loc(*this);
a.sign = loc.sign != a.sign? '\xff': '\0';
a.status = loc.ldiv(a);
return a; // gets remainder
}
bcd bcd::operator/(long n)
{
bcd lv(n, 2*this->nbytes);
bcd loc(*this);
loc.sign = loc.sign != lv.sign? '\xff': '\0';
loc.status = loc.ldiv(lv);
return loc;
}
bcd bcd::operator%(long n)
{
bcd lv(n, 2*this->nbytes);
bcd loc(*this);
lv.sign = loc.sign != lv.sign? '\xff': '\0';
lv.status = loc.ldiv(lv);
return lv;
}
int bcd::cmp(bcd& a)
{
if (sign && !a.sign)
return -1;
if (!sign && a.sign)
return 1;
if (!sign && !a.sign)
return -memrcmp(body,a.body,nbytes);
return memrcmp(body,a.body,nbytes);
}
int bcd::cmp(long n)
{
if (sign && n >= 0L)
return -1;
if (!sign && n < 0L)
return 1;
}
long bcd::tolong()
{
long v = 0L;
unsigned char *p;
for (p = (nbytes >= 5)? body+4: body+nbytes-1; !*p; --p) ;
// 5 bytes is maximum for long - skip over zeros
for (; p >= body; --p) {
v *= 10;
v += 10*(*p >> 4) + (*p & 0xf);
}
if (sign)
v = -v;
return v;
}
bcd::operator double()
{
unsigned char *p;
double dval = 0.0, exp = 1.0;
unsigned long msdec = 0, lsdec = 0;
unsigned long msscale = 1;
p = body+nbytes-1;
while (!*p)
--p;
while (p >= body)
{
if (msdec < (0x7FFFFFFF-10)/10)
msdec = msdec*10 + (*p >> 4);
else if (msscale < (0x7FFFFFFF-10)/10)
{
lsdec = lsdec*10 + (*p >> 4);
msscale *= 10;
}
else
exp *= 10;
if (msdec < (0x7FFFFFFF-10)/10)
msdec = msdec*10 + (*p & 0xf);
else if (msscale < (0x7FFFFFFF-10)/10)
{
lsdec = lsdec*10 + (*p & 0xf);
msscale *= 10;
}
else
exp *= 10;
--p;
}
dval = msdec;
if (msscale != 1) /* if stuff was accumulated in lsdec */
dval = dval * msscale + lsdec;
dval *= exp;
return (sign) ? -dval : dval;
}
PFC set_bcd_handler(PFC handler)
{
PFC loc = bcd_handler;
bcd_handler = handler;
return loc;
}
ostream& operator<<(ostream& s, bcd& a)
{
char buf[80];
a.decode(buf);
return s << buf;
}