/* returns 0 on success, or an errno on failure */
static int
readOrWriteBytes (tr_session * session,
tr_torrent * tor,
int ioMode,
tr_file_index_t fileIndex,
uint64_t fileOffset,
void * buf,
size_t buflen)
{
int fd;
int err = 0;
const bool doWrite = ioMode >= TR_IO_WRITE;
const tr_info * const info = &tor->info;
const tr_file * const file = &info->files[fileIndex];
assert (fileIndex < info->fileCount);
assert (!file->length || (fileOffset < file->length));
assert (fileOffset + buflen <= file->length);
if (!file->length)
return 0;
/***
**** Find the fd
***/
fd = tr_fdFileGetCached (session, tr_torrentId (tor), fileIndex, doWrite);
if (fd < 0)
{
/* it's not cached, so open/create it now */
char * subpath;
const char * base;
/* see if the file exists... */
if (!tr_torrentFindFile2 (tor, fileIndex, &base, &subpath, NULL))
{
/* we can't read a file that doesn't exist... */
if (!doWrite)
err = ENOENT;
/* figure out where the file should go, so we can create it */
base = tr_torrentGetCurrentDir (tor);
subpath = tr_sessionIsIncompleteFileNamingEnabled (tor->session)
? tr_torrentBuildPartial (tor, fileIndex)
: tr_strdup (file->name);
}
if (!err)
{
/* open (and maybe create) the file */
char * filename = tr_buildPath (base, subpath, NULL);
const int prealloc = file->dnd || !doWrite
? TR_PREALLOCATE_NONE
: tor->session->preallocationMode;
if (((fd = tr_fdFileCheckout (session, tor->uniqueId, fileIndex,
filename, doWrite,
prealloc, file->length))) < 0)
{
err = errno;
tr_torerr (tor, "tr_fdFileCheckout failed for \"%s\": %s",
filename, tr_strerror (err));
}
else if (doWrite)
{
/* make a note that we just created a file */
tr_statsFileCreated (tor->session);
}
tr_free (filename);
}
tr_free (subpath);
}
/***
**** Use the fd
***/
if (!err)
{
if (ioMode == TR_IO_READ)
{
const int rc = tr_pread (fd, buf, buflen, fileOffset);
if (rc < 0)
{
err = errno;
tr_torerr (tor, "read failed for \"%s\": %s", file->name, tr_strerror (err));
}
}
else if (ioMode == TR_IO_WRITE)
{
const int rc = tr_pwrite (fd, buf, buflen, fileOffset);
if (rc < 0)
{
err = errno;
tr_torerr (tor, "write failed for \"%s\": %s", file->name, tr_strerror (err));
}
}
else if (ioMode == TR_IO_PREFETCH)
{
tr_prefetch (fd, fileOffset, buflen);
}
else
{
abort ();
}
}
return err;
}
static tr_bool
verifyTorrent( tr_torrent * tor, tr_bool * stopFlag )
{
time_t end;
SHA_CTX sha;
int fd = -1;
int64_t filePos = 0;
tr_bool changed = 0;
tr_bool hadPiece = 0;
time_t lastSleptAt = 0;
uint32_t piecePos = 0;
tr_file_index_t fileIndex = 0;
tr_file_index_t prevFileIndex = !fileIndex;
tr_piece_index_t pieceIndex = 0;
const time_t begin = tr_time( );
const size_t buflen = 1024 * 128; /* 128 KiB buffer */
uint8_t * buffer = tr_valloc( buflen );
SHA1_Init( &sha );
tr_tordbg( tor, "%s", "verifying torrent..." );
tr_torrentSetChecked( tor, 0 );
while( !*stopFlag && ( pieceIndex < tor->info.pieceCount ) )
{
uint32_t leftInPiece;
uint32_t bytesThisPass;
uint64_t leftInFile;
const tr_file * file = &tor->info.files[fileIndex];
/* if we're starting a new piece... */
if( piecePos == 0 )
hadPiece = tr_cpPieceIsComplete( &tor->completion, pieceIndex );
/* if we're starting a new file... */
if( !filePos && (fd<0) && (fileIndex!=prevFileIndex) )
{
char * filename = tr_torrentFindFile( tor, fileIndex );
fd = filename == NULL ? -1 : tr_open_file_for_scanning( filename );
tr_free( filename );
prevFileIndex = fileIndex;
}
/* figure out how much we can read this pass */
leftInPiece = tr_torPieceCountBytes( tor, pieceIndex ) - piecePos;
leftInFile = file->length - filePos;
bytesThisPass = MIN( leftInFile, leftInPiece );
bytesThisPass = MIN( bytesThisPass, buflen );
/* read a bit */
if( fd >= 0 ) {
const ssize_t numRead = tr_pread( fd, buffer, bytesThisPass, filePos );
if( numRead > 0 ) {
bytesThisPass = (uint32_t)numRead;
SHA1_Update( &sha, buffer, bytesThisPass );
#if defined HAVE_POSIX_FADVISE && defined POSIX_FADV_DONTNEED
posix_fadvise( fd, filePos, bytesThisPass, POSIX_FADV_DONTNEED );
#endif
}
}
/* move our offsets */
leftInPiece -= bytesThisPass;
leftInFile -= bytesThisPass;
piecePos += bytesThisPass;
filePos += bytesThisPass;
/* if we're finishing a piece... */
if( leftInPiece == 0 )
{
time_t now;
tr_bool hasPiece;
uint8_t hash[SHA_DIGEST_LENGTH];
SHA1_Final( hash, &sha );
hasPiece = !memcmp( hash, tor->info.pieces[pieceIndex].hash, SHA_DIGEST_LENGTH );
if( hasPiece || hadPiece ) {
tr_torrentSetHasPiece( tor, pieceIndex, hasPiece );
changed |= hasPiece != hadPiece;
}
tr_torrentSetPieceChecked( tor, pieceIndex );
now = tr_time( );
tor->anyDate = now;
/* sleeping even just a few msec per second goes a long
* way towards reducing IO load... */
if( lastSleptAt != now ) {
lastSleptAt = now;
tr_wait_msec( MSEC_TO_SLEEP_PER_SECOND_DURING_VERIFY );
}
SHA1_Init( &sha );
++pieceIndex;
piecePos = 0;
}
/* if we're finishing a file... */
if( leftInFile == 0 )
{
if( fd >= 0 ) { tr_close_file( fd ); fd = -1; }
++fileIndex;
filePos = 0;
}
}
/* cleanup */
if( fd >= 0 )
tr_close_file( fd );
free( buffer );
/* stopwatch */
end = tr_time( );
tr_tordbg( tor, "Verification is done. It took %d seconds to verify %"PRIu64" bytes (%"PRIu64" bytes per second)",
(int)(end-begin), tor->info.totalSize,
(uint64_t)(tor->info.totalSize/(1+(end-begin))) );
return changed;
}
/* returns 0 on success, or an errno on failure */
static int
readOrWriteBytes( tr_session * session,
tr_torrent * tor,
int ioMode,
tr_file_index_t fileIndex,
uint64_t fileOffset,
void * buf,
size_t buflen )
{
const tr_info * info = &tor->info;
const tr_file * file = &info->files[fileIndex];
int fd = -1;
int err = 0;
const tr_bool doWrite = ioMode >= TR_IO_WRITE;
//if( doWrite )
// fprintf( stderr, "in file %s at offset %zu, writing %zu bytes; file length is %zu\n", file->name, (size_t)fileOffset, buflen, (size_t)file->length );
assert( fileIndex < info->fileCount );
assert( !file->length || ( fileOffset < file->length ) );
assert( fileOffset + buflen <= file->length );
if( !file->length )
return 0;
fd = tr_fdFileGetCached( session, tr_torrentId( tor ), fileIndex, doWrite );
if( fd < 0 )
{
/* the fd cache doesn't have this file...
* we'll need to open it and maybe create it */
char * subpath;
const char * base;
tr_bool fileExists;
tr_preallocation_mode preallocationMode;
fileExists = tr_torrentFindFile2( tor, fileIndex, &base, &subpath );
if( !fileExists )
{
base = tr_torrentGetCurrentDir( tor );
if( tr_sessionIsIncompleteFileNamingEnabled( tor->session ) )
subpath = tr_torrentBuildPartial( tor, fileIndex );
else
subpath = tr_strdup( file->name );
}
if( ( file->dnd ) || ( ioMode < TR_IO_WRITE ) )
preallocationMode = TR_PREALLOCATE_NONE;
else
preallocationMode = tor->session->preallocationMode;
if( ( ioMode < TR_IO_WRITE ) && !fileExists ) /* does file exist? */
{
err = ENOENT;
}
else
{
char * filename = tr_buildPath( base, subpath, NULL );
if( ( fd = tr_fdFileCheckout( session, tor->uniqueId, fileIndex, filename,
doWrite, preallocationMode, file->length ) ) < 0 )
{
err = errno;
tr_torerr( tor, "tr_fdFileCheckout failed for \"%s\": %s", filename, tr_strerror( err ) );
}
tr_free( filename );
}
if( doWrite && !err )
tr_statsFileCreated( tor->session );
tr_free( subpath );
}
if( !err )
{
/* check & see if someone deleted the file while it was in our cache */
struct stat sb;
const tr_bool file_disappeared = fstat( fd, &sb ) || sb.st_nlink < 1;
if( file_disappeared ) {
tr_torrentSetLocalError( tor, "Please Verify Local Data! A file disappeared: \"%s\"", tor->info.files[fileIndex].name );
err = ENOENT;
}
if( ioMode == TR_IO_READ ) {
const int rc = tr_pread( fd, buf, buflen, fileOffset );
if( rc < 0 ) {
err = errno;
tr_torerr( tor, "read failed for \"%s\": %s",
file->name, tr_strerror( err ) );
}
} else if( ioMode == TR_IO_PREFETCH ) {
const int rc = tr_prefetch( fd, fileOffset, buflen );
if( rc < 0 ) {
/* (don't set "err" here... it's okay for prefetch to fail) */
tr_tordbg( tor, "prefetch failed for \"%s\": %s",
file->name, tr_strerror( errno ) );
}
} else if( ioMode == TR_IO_WRITE ) {
const int rc = tr_pwrite( fd, buf, buflen, fileOffset );
if( rc < 0 ) {
err = errno;
tr_torerr( tor, "write failed for \"%s\": %s",
file->name, tr_strerror( err ) );
}
} else {
abort();
}
}
return err;
}