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#include <u.h>
#include <libc.h>
#include <venti.h>
#include "cvt.h"
static int
checksize(int n)
{
if(n < 256) {
werrstr("bad block size");
return -1;
}
return 0;
}
extern int vttobig(ulong);
void
vtrootpack(VtRoot *r, uchar *p)
{
uchar *op = p;
int vers, bsize;
vers = VtRootVersion;
bsize = r->blocksize;
if(bsize >= (1<<16)) {
vers |= _VtRootVersionBig;
bsize = vttobig(bsize);
if(bsize < 0)
sysfatal("invalid root blocksize: %#lx", r->blocksize);
}
U16PUT(p, vers);
p += 2;
memmove(p, r->name, sizeof(r->name));
p += sizeof(r->name);
memmove(p, r->type, sizeof(r->type));
p += sizeof(r->type);
memmove(p, r->score, VtScoreSize);
p += VtScoreSize;
U16PUT(p, bsize);
p += 2;
memmove(p, r->prev, VtScoreSize);
p += VtScoreSize;
assert(p-op == VtRootSize);
}
int
vtrootunpack(VtRoot *r, uchar *p)
{
uchar *op = p;
uint vers;
memset(r, 0, sizeof(*r));
vers = U16GET(p);
if((vers&~_VtRootVersionBig) != VtRootVersion) {
werrstr("unknown root version");
return -1;
}
p += 2;
memmove(r->name, p, sizeof(r->name));
r->name[sizeof(r->name)-1] = 0;
p += sizeof(r->name);
memmove(r->type, p, sizeof(r->type));
r->type[sizeof(r->type)-1] = 0;
p += sizeof(r->type);
memmove(r->score, p, VtScoreSize);
p += VtScoreSize;
r->blocksize = U16GET(p);
if(vers & _VtRootVersionBig)
r->blocksize = (r->blocksize >> 5) << (r->blocksize & 31);
if(checksize(r->blocksize) < 0)
return -1;
p += 2;
memmove(r->prev, p, VtScoreSize);
p += VtScoreSize;
assert(p-op == VtRootSize);
return 0;
}
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