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#include <u.h>
#include <libc.h>
#include <venti.h>
#include "cvt.h"
static int
checksize(int n)
{
if(n < 256 || n > VtMaxLumpSize) {
werrstr("bad block size %#ux", n);
return -1;
}
return 0;
}
void
vtentrypack(VtEntry *e, uchar *p, int index)
{
ulong t32;
int flags;
uchar *op;
int depth;
p += index * VtEntrySize;
op = p;
U32PUT(p, e->gen);
p += 4;
U16PUT(p, e->psize);
p += 2;
U16PUT(p, e->dsize);
p += 2;
depth = e->type&VtTypeDepthMask;
flags = (e->flags&~(_VtEntryDir|_VtEntryDepthMask));
flags |= depth << _VtEntryDepthShift;
if(e->type - depth == VtDirType)
flags |= _VtEntryDir;
U8PUT(p, flags);
p++;
memset(p, 0, 5);
p += 5;
U48PUT(p, e->size, t32);
p += 6;
memmove(p, e->score, VtScoreSize);
p += VtScoreSize;
assert(p-op == VtEntrySize);
}
int
vtentryunpack(VtEntry *e, uchar *p, int index)
{
uchar *op;
p += index * VtEntrySize;
op = p;
e->gen = U32GET(p);
p += 4;
e->psize = U16GET(p);
p += 2;
e->dsize = U16GET(p);
p += 2;
e->flags = U8GET(p);
e->type = (e->flags&_VtEntryDir) ? VtDirType : VtDataType;
e->type += (e->flags & _VtEntryDepthMask) >> _VtEntryDepthShift;
e->flags &= ~(_VtEntryDir|_VtEntryDepthMask);
p++;
p += 5;
e->size = U48GET(p);
p += 6;
memmove(e->score, p, VtScoreSize);
p += VtScoreSize;
assert(p-op == VtEntrySize);
if(!(e->flags & VtEntryActive))
return 0;
/*
* Some old vac files use psize==0 and dsize==0 when the
* file itself has size 0 or is zeros. Just to make programs not
* have to figure out what block sizes of 0 means, rewrite them.
*/
if(e->psize == 0 && e->dsize == 0
&& memcmp(e->score, vtzeroscore, VtScoreSize) == 0){
e->psize = 4096;
e->dsize = 4096;
}
if(checksize(e->psize) < 0 || checksize(e->dsize) < 0)
return -1;
return 0;
}
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