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#include "defs.h"
#include "global.h"
char *
alloc_check(p, e)
char *p, *e;
{
if (p == NULL)
Fatal("can't malloc space for %s", e);
return p;
}
int
makeuint(s, n) /* return n byte quantity from string */
byte *s;
int n;
{
int x; /* number being constructed */
x = 0;
while (n--) {
x <<= 8;
x |= *s++;
}
return x;
}
int
makeint(s, n) /* return n byte quantity from string */
byte *s;
int n;
{
int n1; /* number of bytes */
int x; /* number being constructed */
x = *s++; /* get first (high-order) byte */
n1 = n--;
while (n--) {
x <<= 8;
x |= *s++;
}
/* NOTE: This code assumes that the right-shift is an arithmetic, rather
than logical, shift which will propagate the sign bit right. According
to Kernighan and Ritchie, this is compiler dependent! */
x<<=32-8*n1;
x>>=32-8*n1; /* sign extend */
return x;
}
static int i2b();
int
uinttob(b, x)
byte *b;
unsigned int x;
{
static unsigned char buf[sizeof(int)+1];
int i, j, n;
if (x == 0) {
b[0] = 0;
return 1;
}
n = i2b((unsigned int)x, buf);
for (i = 1; i+1 < n && buf[i] == 0; i++)
;
for (j = i; j < n; j++)
b[j-i] = buf[j];
return n-i;
}
int
inttob(b, x)
byte *b;
int x;
{
static unsigned char buf[sizeof(int)+1];
int i, j, n;
if (x == 0) {
b[0] = 0;
return 1;
}
n = i2b((unsigned int)x, buf);
if (x > 0)
for (i = 0; i+1 < n && buf[i] == 0 && (buf[i+1]&0x80) == 0; i++)
;
else
for (i = 1; i+1 < n && buf[i] == 0xff && (buf[i+1]&0x80); i++)
;
for (j = i; j < n; j++)
b[j-i] = buf[j];
return n-i;
}
static
int
i2b(x, b)
unsigned int x;
unsigned char *b;
{
int n;
if (x == 0) {
*b = 0;
return 1;
}
n = i2b(x>>8, b);
*(b+n) = x & 0xff;
return n+1;
}
int
numstr(s)
char *s;
{
for (; *s != '\0'; s++)
if (!isdigit(*s))
return FALSE;
return TRUE;
}
char *
strsave(s)
char *s;
{
char *t;
int len;
if ((t = malloc((unsigned)(len = strlen(s)+1))) == NULL)
Fatal("cannot save string %s", s);
bcopy(s, t, len);
return t;
}
/* getstrtok:
* find the first c in d, put '\0' there, and let *e point the next position.
*/
int
getstrtok(d, c, e)
char *d;
char c;
char **e;
{
for (; *d != c && *d != '\0'; d++)
;
if (*d == c) {
*d = '\0';
*e = d+1;
return TRUE;
}
return FALSE;
}
void
skipstrblank(d, e)
char *d;
char **e;
{
for (; *d == ' ' || *d == '\t'; d++)
;
*e = d;
}
#define LOWP 16
#define FIXP 20
#define LOWMASK ((1<<LOWP)-1)
#define D (1<<(FIXP-LOWP))
#define H (1<<(2*LOWP-FIXP))
#define TPT(x, y) ((x)<<(y)) /* x * 2^y */
#define DPT(x, y) ((x)>>(y)) /* x / 2^y */
int
scale_exact(s, d)
int s, d;
{
int sign;
unsigned int s1, s0, d1, d0;
if (s < 0) {
sign = -1;
s *= -1;
} else
sign = 1;
s0 = s & LOWMASK;
d0 = d & LOWMASK;
s1 = s >> LOWP;
d1 = d >> LOWP;
return (sign *
(TPT(s1*d1, 2*LOWP-FIXP) +
DPT(s1*d0+s0*d1 + DPT(s0*d0, LOWP), FIXP-LOWP))
);
}
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