Import sources from 2011-03-30 iso image

1 files changed, 95 insertions, 0 deletions

diff --git a/sys/src/libventi/entry.c b/sys/src/libventi/entry.c
new file mode 100755
index 000000000..aeb8dada3
--- /dev/null
+++ b/sys/src/libventi/entry.c
@@ -0,0 +1,95 @@
+#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;
+}
+