#include <u.h>
#include <libc.h>
#include <venti.h>
enum
{
VtEntrySize = 40,
VtRootSize = 300,
VtScoreSize = 20,
};
typedef struct VtEntry
{
ulong gen; /* generation number */
ushort psize; /* pointer block size */
ushort dsize; /* data block size */
uchar type;
uchar flags;
uvlong size;
uchar score[VtScoreSize];
} VtEntry;
typedef struct VtRoot
{
char name[128];
char type[128];
uchar score[VtScoreSize]; /* to a Dir block */
ushort blocksize; /* maximum block size */
uchar prev[VtScoreSize]; /* previous root block */
} VtRoot;
void vtentrypack(VtEntry *e, uchar *buf, int index)
int vtentryunpack(VtEntry *e, uchar *buf, int index)
Packet* vtfcallpack(VtFcall *f)
int vtfcallunpack(VtFcall *f, Packet *p)
void vtfcallclear(VtFcall *f)
uint vttodisktype(uint type)
uint vtfromdisktype(uint type)
int vtputstring(Packet *p, char *s)
int vtgetstring(Packet *p, char **s)
void vtrootpack(VtRoot *r, uchar *buf)
int vtrootunpack(VtRoot *r, uchar *buf)
int vtparsescore(char *s, char **prefix, uchar score[VtScoreSize])
int vtfcallfmt(Fmt *fmt)
int vtscorefmt(Fmt *fmt)
DESCRIPTIONThese routines convert between C representations of Venti
structures and serialized representations used on disk and
on the network.
Vtentrypack converts a
VtEntry structure describing a Venti file
(see
.MR venti (7) )
into a 40-byte
( VtEntrySize ) structure at
buf + index *40 . Vtentryunpack
does the reverse conversion.
Vtfcallpack converts a
VtFcall structure describing a Venti protocol message
(see
.MR venti (7) )
into a packet.
Vtfcallunpack does the reverse conversion.
The fields in a
VtFcall are named after the protocol fields described in
.MR venti (7) ,
except that the
type field is renamed
blocktype . The
msgtype field holds the one-byte message type:
VtThello , VtRhello , and so on.
Vtfcallclear frees the strings
f ->error , f ->version , f ->uid , f ->sid , the buffers
f ->crypto and
f ->codec , and the packet
f ->data .
The block type enumeration defined in
<venti.h> (presented in
.MR venti (7) )
differs from the one used on disk and in the network
protocol.
The disk and network representation uses different
constants and does not distinguish between
VtDataType+ n and
VtDirType+ n blocks.
Vttodisktype converts a
<venti.h> enumeration value to the disk value;
vtfromdisktype converts a disk value to the enumeration value,
always using the
VtDirType pointers.
The
VtFcall field
blocktype is an enumeration value
( vtfcallpack and
vtfcallunpack convert to and from the disk values used in packets
automatically),
so most programs will not need to call these functions.
Vtputstring appends the Venti protocol representation of the string
s to the packet
p . Vtgetstring reads a string from the packet, returning a pointer to a copy
of the string in
* s . The copy must be freed by the caller.
These functions are used by
vtfcallpack and
vtfcallunpack ; most programs will not need to call them directly.
Vtrootpack converts a
VtRoot structure describing a Venti file tree
into the 300-byte
( VtRootSize ) buffer pointed to by
buf . Vtrootunpack does the reverse conversion.
Vtparsescore parses the 40-digit hexadecimal string
s , writing its value
into
score . If the hexadecimal string is prefixed with
a text label followed by a colon, a copy of that
label is returned in
* prefix . If
prefix is nil, the label is ignored.
Vtfcallfmt and
vtscorefmt are
.MR print (3)
formatters to print
VtFcall structures and scores.
Vtfcallfmt assumes that
vtscorefmt is installed as
%V .
SOURCE \*9/src/libventi SEE ALSO.MR venti (1) ,
.MR venti (3) ,
.MR venti (7)
DIAGNOSTICS Vtentrypack , vtfcallpack , vtrootpack , and
vtfcallclear cannot fail.
Vtentryunpack , vtrootunpack , vtputstring , vtgetstring , and
vtparsescore return 0 on success, -1 on error.
Vtfcallpack returns a packet on success, nil on error.
Vttodisktype and
vtfromdisktype return
VtCorruptType (255)
when presented with invalid input.