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#include <u.h>
#include <libc.h>
#include "dat.h"
#include "fns.h"
static ulong
get4(uchar *p)
{
return p[0]<<24 | p[1]<<16 | p[2]<<8 | p[3];
}
static void
put4(uchar *p, ulong u)
{
p[0] = u>>24, p[1] = u>>16, p[2] = u>>8, p[3] = u;
}
static int
vpack(uchar *p, int n, char *fmt, va_list a)
{
uchar *p0 = p, *e = p+n;
FPdbleword d;
for(;;){
switch(*fmt++){
case '\0':
return p - p0;
case 'd':
d.x = va_arg(a, double);
if(p+8 > e)
goto err;
put4(p, d.hi), p += 4;
put4(p, d.lo), p += 4;
break;
}
}
err:
return -1;
}
static int
vunpack(uchar *p, int n, char *fmt, va_list a)
{
uchar *p0 = p, *e = p+n;
FPdbleword d;
for(;;){
switch(*fmt++){
case '\0':
return p - p0;
case 'd':
if(p+8 > e)
goto err;
d.hi = get4(p), p += 4;
d.lo = get4(p), p += 4;
*va_arg(a, double*) = d.x;
break;
}
}
err:
return -1;
}
int
pack(uchar *p, int n, char *fmt, ...)
{
va_list a;
va_start(a, fmt);
n = vpack(p, n, fmt, a);
va_end(a);
return n;
}
int
unpack(uchar *p, int n, char *fmt, ...)
{
va_list a;
va_start(a, fmt);
n = vunpack(p, n, fmt, a);
va_end(a);
return n;
}
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