transmission/libtransmission/fastresume.c

602 lines
16 KiB
C

/******************************************************************************
* $Id$
*
* Copyright (c) 2005-2008 Transmission authors and contributors
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*****************************************************************************/
/*
* NOTE: THIS FILE IS DEPRECATED
*
* The fastresume file format is brittle and was replaced in Transmission 1.20
* with the benc-formatted ".resume" files implemented in resume.[ch].
*
* This older format is kept only for reading older resume files for users
* who upgrade from older versions of Transmission, and may be removed
* after more time has passed.
*/
/***********************************************************************
* Fast resume
***********************************************************************
* The format of the resume file is a 4 byte format version (currently 1),
* followed by several variable-sized blocks of data. Each block is
* preceded by a 1 byte ID and a 4 byte length. The currently recognized
* IDs are defined below by the FR_ID_* macros. The length does not include
* the 5 bytes for the ID and length.
*
* The name of the resume file is "resume.<hash>-<tag>", although
* older files with a name of "resume.<hash>" will be recognized if
* the former doesn't exist.
*
* All values are stored in the native endianness. Moving a
* libtransmission resume file from an architecture to another will not
* work, although it will not hurt either (the version will be wrong,
* so the resume file will not be read).
**********************************************************************/
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h> /* calloc */
#include <string.h> /* strcpy, memset, memcmp */
#include <sys/types.h>
#include <sys/stat.h> /* stat */
#include <unistd.h> /* unlink */
#include "transmission.h"
#include "session.h"
#include "completion.h"
#include "fastresume.h"
#include "peer-mgr.h"
#include "platform.h"
#include "resume.h" /* TR_FR_ bitwise enum */
#include "torrent.h"
#include "utils.h"
/* time_t can be 32 or 64 bits... for consistency we'll hardwire 64 */
typedef uint64_t tr_time_t;
enum
{
/* number of bytes downloaded */
FR_ID_DOWNLOADED = 2,
/* number of bytes uploaded */
FR_ID_UPLOADED = 3,
/* progress data:
* - 4 bytes * number of files: mtimes of files
* - 1 bit * number of blocks: whether we have the block or not */
FR_ID_PROGRESS = 5,
/* dnd and priority
* char * number of files: l,n,h for low, normal, high priority
* char * number of files: t,f for DND flags */
FR_ID_PRIORITY = 6,
/* transfer speeds
* uint32_t: dl speed rate to use when the mode is single
* uint32_t: dl's tr_speedlimit
* uint32_t: ul speed rate to use when the mode is single
* uint32_t: ul's tr_speedlimit
*/
FR_ID_SPEED = 8,
/* active
* char: 't' if running, 'f' if paused
*/
FR_ID_RUN = 9,
/* number of corrupt bytes downloaded */
FR_ID_CORRUPT = 10,
/* IPs and ports of connectable peers */
FR_ID_PEERS = 11,
/* download dir of the torrent: zero-terminated string */
FR_ID_DOWNLOAD_DIR = 12,
/* pex flag
* 't' if pex is enabled, 'f' if disabled */
FR_ID_PEX = 13,
/* max connected peers -- uint16_t */
FR_ID_MAX_PEERS = 14
};
/* macros for the length of various pieces of the progress data */
#define FR_MTIME_LEN( t ) \
( sizeof( tr_time_t ) * ( t )->info.fileCount )
#define FR_BLOCK_BITFIELD_LEN( t ) \
( ( ( t )->blockCount + 7u ) / 8u )
#define FR_PROGRESS_LEN( t ) \
( FR_MTIME_LEN( t ) + FR_BLOCK_BITFIELD_LEN( t ) )
#define FR_SPEED_LEN ( 2 * ( sizeof( uint16_t ) + sizeof( uint8_t ) ) )
static tr_time_t*
getMTimes( const tr_torrent * tor,
int * setme_n )
{
int i;
const int n = tor->info.fileCount;
tr_time_t * m = calloc( n, sizeof( tr_time_t ) );
for( i = 0; i < n; ++i )
{
struct stat sb;
char * fname = tr_buildPath( tor->downloadDir, tor->info.files[i].name, NULL );
if( !stat( fname, &sb ) && S_ISREG( sb.st_mode ) )
{
#ifdef SYS_DARWIN
m[i] = sb.st_mtimespec.tv_sec;
#else
m[i] = sb.st_mtime;
#endif
}
tr_free( fname );
}
*setme_n = n;
return m;
}
/***
****
***/
static uint64_t
internalIdToPublicBitfield( uint8_t id )
{
uint64_t ret = 0;
switch( id )
{
case FR_ID_DOWNLOADED:
ret = TR_FR_DOWNLOADED; break;
case FR_ID_UPLOADED:
ret = TR_FR_UPLOADED; break;
case FR_ID_PROGRESS:
ret = TR_FR_PROGRESS; break;
case FR_ID_PRIORITY:
ret = TR_FR_PRIORITY; break;
case FR_ID_SPEED:
ret = TR_FR_SPEEDLIMIT; break;
case FR_ID_RUN:
ret = TR_FR_RUN; break;
case FR_ID_CORRUPT:
ret = TR_FR_CORRUPT; break;
case FR_ID_PEERS:
ret = TR_FR_PEERS; break;
case FR_ID_DOWNLOAD_DIR:
ret = TR_FR_DOWNLOAD_DIR; break;
case FR_ID_MAX_PEERS:
ret = TR_FR_MAX_PEERS; break;
}
return ret;
}
static void
readBytes( void * target,
const uint8_t ** source,
size_t byteCount )
{
memcpy( target, *source, byteCount );
*source += byteCount;
}
static uint64_t
parseDownloaded( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
if( len != sizeof( uint64_t ) )
return 0;
readBytes( &tor->downloadedPrev, &buf, sizeof( uint64_t ) );
return TR_FR_DOWNLOADED;
}
static uint64_t
parseUploaded( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
if( len != sizeof( uint64_t ) )
return 0;
readBytes( &tor->uploadedPrev, &buf, sizeof( uint64_t ) );
return TR_FR_UPLOADED;
}
static uint64_t
parseCorrupt( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
if( len != sizeof( uint64_t ) )
return 0;
readBytes( &tor->corruptPrev, &buf, sizeof( uint64_t ) );
return TR_FR_CORRUPT;
}
static uint64_t
parseConnections( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
if( len != sizeof( uint16_t ) )
return 0;
readBytes( &tor->maxConnectedPeers, &buf, sizeof( uint16_t ) );
return TR_FR_MAX_PEERS;
}
static uint64_t
parseProgress( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
uint64_t ret = 0;
if( len == FR_PROGRESS_LEN( tor ) )
{
int i;
int n;
tr_bitfield bitfield;
/* compare file mtimes */
tr_time_t * curMTimes = getMTimes( tor, &n );
const uint8_t * walk = buf;
tr_time_t mtime;
for( i = 0; i < n; ++i )
{
readBytes( &mtime, &walk, sizeof( tr_time_t ) );
if( curMTimes[i] == mtime )
tr_torrentSetFileChecked( tor, i, TRUE );
else
{
tr_torrentSetFileChecked( tor, i, FALSE );
tr_tordbg( tor, "Torrent needs to be verified" );
}
}
free( curMTimes );
/* get the completion bitfield */
memset( &bitfield, 0, sizeof bitfield );
bitfield.byteCount = FR_BLOCK_BITFIELD_LEN( tor );
bitfield.bitCount = bitfield.byteCount * 8;
bitfield.bits = (uint8_t*) walk;
if( tr_cpBlockBitfieldSet( &tor->completion, &bitfield ) )
ret = TR_FR_PROGRESS;
else {
tr_torrentUncheck( tor );
tr_tordbg( tor, "Torrent needs to be verified" );
}
}
/* the files whose mtimes are wrong,
remove from completion pending a recheck... */
{
tr_piece_index_t i;
for( i = 0; i < tor->info.pieceCount; ++i )
if( !tr_torrentIsPieceChecked( tor, i ) )
tr_cpPieceRem( &tor->completion, i );
}
return ret;
}
static uint64_t
parsePriorities( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
uint64_t ret = 0;
if( len == (uint32_t)( 2 * tor->info.fileCount ) )
{
const size_t n = tor->info.fileCount;
const uint8_t * walk = buf;
tr_file_index_t *dnd = NULL, dndCount = 0;
tr_file_index_t *dl = NULL, dlCount = 0;
size_t i;
len = 2 * n;
/* set file priorities */
for( i = 0; i < n; ++i )
{
tr_priority_t priority;
const char ch = *walk++;
switch( ch )
{
case 'l':
priority = TR_PRI_LOW; break;
case 'h':
priority = TR_PRI_HIGH; break;
default:
priority = TR_PRI_NORMAL; break;
}
tr_torrentInitFilePriority( tor, i, priority );
}
/* set the dnd flags */
dl = tr_new( tr_file_index_t, len );
dnd = tr_new( tr_file_index_t, len );
for( i = 0; i < n; ++i )
if( *walk++ == 't' ) /* 't' means the DND flag is true */
dnd[dndCount++] = i;
else
dl[dlCount++] = i;
if( dndCount )
tr_torrentInitFileDLs ( tor, dnd, dndCount, FALSE );
if( dlCount )
tr_torrentInitFileDLs ( tor, dl, dlCount, TRUE );
tr_free( dnd );
tr_free( dl );
ret = TR_FR_PRIORITY;
}
return ret;
}
static uint64_t
parseSpeedLimit( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
uint64_t ret = 0;
if( len == FR_SPEED_LEN )
{
uint8_t i8;
uint16_t i16;
readBytes( &i16, &buf, sizeof( i16 ) );
tr_torrentSetSpeedLimit( tor, TR_DOWN, i16 );
readBytes( &i8, &buf, sizeof( i8 ) );
tr_torrentSetSpeedMode( tor, TR_DOWN, (tr_speedlimit)i8 );
readBytes( &i16, &buf, sizeof( i16 ) );
tr_torrentSetSpeedLimit( tor, TR_UP, i16 );
readBytes( &i8, &buf, sizeof( i8 ) );
tr_torrentSetSpeedMode( tor, TR_UP, (tr_speedlimit)i8 );
ret = TR_FR_SPEEDLIMIT;
}
return ret;
}
static uint64_t
parseRun( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
if( len != 1 )
return 0;
tor->isRunning = *buf == 't';
return TR_FR_RUN;
}
static uint64_t
parsePeers( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
uint64_t ret = 0;
if( !tor->info.isPrivate )
{
int i;
const int count = len / sizeof( tr_pex );
for( i = 0; i < count; ++i )
{
tr_pex pex;
readBytes( &pex, &buf, sizeof( tr_pex ) );
tr_peerMgrAddPex( tor, TR_PEER_FROM_CACHE, &pex );
}
tr_tordbg( tor, "Loaded %d peers from resume file", count );
ret = TR_FR_PEERS;
}
return ret;
}
static uint64_t
parseDownloadDir( tr_torrent * tor,
const uint8_t * buf,
uint32_t len )
{
uint64_t ret = 0;
if( buf && *buf && len )
{
tr_free( tor->downloadDir );
tor->downloadDir = tr_strndup( (char*)buf, len );
ret = TR_FR_DOWNLOAD_DIR;
}
return ret;
}
static uint64_t
parseVersion1( tr_torrent * tor,
const uint8_t * buf,
const uint8_t * end,
uint64_t fieldsToLoad )
{
uint64_t ret = 0;
while( end - buf >= 5 )
{
uint8_t id;
uint32_t len;
readBytes( &id, &buf, sizeof( id ) );
readBytes( &len, &buf, sizeof( len ) );
if( buf + len > end )
{
tr_torerr( tor, "Resume file seems to be corrupt. Skipping." );
}
else if( fieldsToLoad &
internalIdToPublicBitfield( id ) ) switch( id )
{
case FR_ID_DOWNLOADED:
ret |= parseDownloaded( tor, buf, len ); break;
case FR_ID_UPLOADED:
ret |= parseUploaded( tor, buf, len ); break;
case FR_ID_PROGRESS:
ret |= parseProgress( tor, buf, len ); break;
case FR_ID_PRIORITY:
ret |= parsePriorities( tor, buf, len ); break;
case FR_ID_SPEED:
ret |= parseSpeedLimit( tor, buf, len ); break;
case FR_ID_RUN:
ret |= parseRun( tor, buf, len ); break;
case FR_ID_CORRUPT:
ret |= parseCorrupt( tor, buf, len ); break;
case FR_ID_PEERS:
ret |= parsePeers( tor, buf, len ); break;
case FR_ID_MAX_PEERS:
ret |= parseConnections( tor, buf, len ); break;
case FR_ID_DOWNLOAD_DIR:
ret |= parseDownloadDir( tor, buf, len ); break;
default:
tr_tordbg( tor, "Skipping unknown resume code %d",
(int)id ); break;
}
buf += len;
}
return ret;
}
static uint8_t*
loadResumeFile( const tr_torrent * tor,
size_t * len )
{
uint8_t * ret = NULL;
const char * cacheDir = tr_getResumeDir( tor->session );
const char * hash = tor->info.hashString;
if( !ret && tor->session->tag )
{
char * path = tr_strdup_printf( "%s" TR_PATH_DELIMITER_STR "%s-%s", cacheDir, hash, tor->session->tag );
ret = tr_loadFile( path, len );
tr_free( path );
}
if( !ret )
{
char * path = tr_buildPath( cacheDir, hash, NULL );
ret = tr_loadFile( path, len );
tr_free( path );
}
return ret;
}
static uint64_t
fastResumeLoadImpl( tr_torrent * tor,
uint64_t fieldsToLoad )
{
uint64_t ret = 0;
size_t size = 0;
uint8_t * buf = loadResumeFile( tor, &size );
if( !buf )
/* %s is the torrent name */
tr_torinf( tor, _( "Couldn't read resume file" ) );
else
{
const uint8_t * walk = buf;
const uint8_t * end = walk + size;
if( end - walk >= 4 )
{
uint32_t version;
readBytes( &version, &walk, sizeof( version ) );
if( version == 1 )
ret |= parseVersion1 ( tor, walk, end, fieldsToLoad );
else
/* %s is the torrent name */
tr_torinf( tor, _( "Couldn't read resume file" ) );
}
tr_free( buf );
}
return ret;
}
uint64_t
tr_fastResumeLoad( tr_torrent * tor,
uint64_t fieldsToLoad )
{
return fastResumeLoadImpl( tor, fieldsToLoad );
}
void
tr_fastResumeRemove( const tr_torrent * tor )
{
const char * cacheDir = tr_getResumeDir( tor->session );
const char * hash = tor->info.hashString;
if( tor->session->tag )
{
char * path = tr_strdup_printf( "%s" TR_PATH_DELIMITER_STR "%s-%s", cacheDir, hash, tor->session->tag );
unlink( path );
tr_free( path );
}
else
{
char * path = tr_buildPath( cacheDir, hash, NULL );
unlink( path );
tr_free( path );
}
}