size_type file::get_size(error_code& ec) const
{
#ifdef TORRENT_WINDOWS
LARGE_INTEGER file_size;
if (!GetFileSizeEx(m_file_handle, &file_size))
{
ec = error_code(GetLastError(), get_system_category());
return -1;
}
return file_size.QuadPart;
#else
struct stat fs;
if (fstat(m_fd, &fs) != 0)
{
ec = error_code(errno, get_posix_category());
return -1;
}
return fs.st_size;
#endif
}
bool file::set_size(size_type s, error_code& ec)
{
TORRENT_ASSERT(is_open());
TORRENT_ASSERT(s >= 0);
#ifdef TORRENT_WINDOWS
LARGE_INTEGER offs;
LARGE_INTEGER cur_size;
if (GetFileSizeEx(m_file_handle, &cur_size) == FALSE)
{
ec = error_code(GetLastError(), get_system_category());
return false;
}
offs.QuadPart = s;
// only set the file size if it's not already at
// the right size. We don't want to update the
// modification time if we don't have to
if (cur_size.QuadPart != s)
{
if (SetFilePointerEx(m_file_handle, offs, &offs, FILE_BEGIN) == FALSE)
{
ec.assign(GetLastError(), get_system_category());
return false;
}
if (::SetEndOfFile(m_file_handle) == FALSE)
{
ec.assign(GetLastError(), get_system_category());
return false;
}
}
#if _WIN32_WINNT >= 0x501
if ((m_open_mode & sparse) == 0)
{
// only allocate the space if the file
// is not fully allocated
DWORD high_dword = 0;
offs.LowPart = GetCompressedFileSize(m_path.c_str(), &high_dword);
offs.HighPart = high_dword;
ec.assign(GetLastError(), get_system_category());
if (ec) return false;
if (offs.QuadPart != s)
{
// if the user has permissions, avoid filling
// the file with zeroes, but just fill it with
// garbage instead
SetFileValidData(m_file_handle, offs.QuadPart);
}
}
#endif // _WIN32_WINNT >= 0x501
#else // NON-WINDOWS
struct stat st;
if (fstat(m_fd, &st) != 0)
{
ec.assign(errno, get_posix_category());
return false;
}
// only truncate the file if it doesn't already
// have the right size. We don't want to update
if (st.st_size != s && ftruncate(m_fd, s) < 0)
{
ec.assign(errno, get_posix_category());
return false;
}
// if we're not in sparse mode, allocate the storage
// but only if the number of allocated blocks for the file
// is less than the file size. Otherwise we would just
// update the modification time of the file for no good
// reason.
if ((m_open_mode & sparse) == 0
&& st.st_blocks < (s + st.st_blksize - 1) / st.st_blksize)
{
// How do we know that the file is already allocated?
// if we always try to allocate the space, we'll update
// the modification time without actually changing the file
// but if we don't do anything if the file size is
#ifdef F_PREALLOCATE
fstore_t f = {F_ALLOCATECONTIG, F_PEOFPOSMODE, 0, s, 0};
if (fcntl(m_fd, F_PREALLOCATE, &f) < 0)
{
ec = error_code(errno, get_posix_category());
return false;
}
#endif // F_PREALLOCATE
#if defined TORRENT_LINUX || TORRENT_HAS_FALLOCATE
int ret;
#endif
#if defined TORRENT_LINUX
ret = my_fallocate(m_fd, 0, 0, s);
// if we return 0, everything went fine
// the fallocate call succeeded
if (ret == 0) return true;
// otherwise, something went wrong. If the error
// is ENOSYS, just keep going and do it the old-fashioned
// way. If fallocate failed with some other error, it
// probably means the user should know about it, error out
// and report it.
if (errno != ENOSYS && errno != EOPNOTSUPP)
{
ec.assign(errno, get_posix_category());
return false;
}
#endif // TORRENT_LINUX
#if TORRENT_HAS_FALLOCATE
// if fallocate failed, we have to use posix_fallocate
// which can be painfully slow
// if you get a compile error here, you might want to
// define TORRENT_HAS_FALLOCATE to 0.
ret = posix_fallocate(m_fd, 0, s);
// posix_allocate fails with EINVAL in case the underlying
// filesystem does bot support this operation
if (ret != 0 && ret != EINVAL)
{
ec = error_code(ret, get_posix_category());
return false;
}
#endif // TORRENT_HAS_FALLOCATE
}
#endif // TORRENT_WINDOWS
return true;
}
size_type file::writev(size_type file_offset, iovec_t const* bufs, int num_bufs, error_code& ec)
{
TORRENT_ASSERT((m_open_mode & rw_mask) == write_only || (m_open_mode & rw_mask) == read_write);
TORRENT_ASSERT(bufs);
TORRENT_ASSERT(num_bufs > 0);
TORRENT_ASSERT(is_open());
#if defined TORRENT_WINDOWS || defined TORRENT_LINUX || defined TORRENT_DEBUG
// make sure m_page_size is initialized
init_file();
#endif
#ifdef TORRENT_DEBUG
if (m_open_mode & no_buffer)
{
bool eof = false;
int size = 0;
// when opened in no_buffer mode, the file_offset must
// be aligned to pos_alignment()
TORRENT_ASSERT((file_offset & (pos_alignment()-1)) == 0);
for (file::iovec_t const* i = bufs, *end(bufs + num_bufs); i < end; ++i)
{
TORRENT_ASSERT((uintptr_t(i->iov_base) & (buf_alignment()-1)) == 0);
// every buffer must be a multiple of the page size
// except for the last one
TORRENT_ASSERT((i->iov_len & (size_alignment()-1)) == 0 || i == end-1);
if ((i->iov_len & (size_alignment()-1)) != 0) eof = true;
size += i->iov_len;
}
error_code code;
if (eof) TORRENT_ASSERT(file_offset + size >= get_size(code));
}
#endif
#ifdef TORRENT_WINDOWS
DWORD ret = 0;
// since the ReadFileScatter requires the file to be opened
// with no buffering, and no buffering requires page aligned
// buffers, open the file in non-buffered mode in case the
// buffer is not aligned. Most of the times the buffer should
// be aligned though
if ((m_open_mode & no_buffer) == 0)
{
// this means the buffer base or the buffer size is not aligned
// to the page size. Use a regular file for this operation.
LARGE_INTEGER offs;
offs.QuadPart = file_offset;
if (SetFilePointerEx(m_file_handle, offs, &offs, FILE_BEGIN) == FALSE)
{
ec = error_code(GetLastError(), get_system_category());
return -1;
}
for (file::iovec_t const* i = bufs, *end(bufs + num_bufs); i < end; ++i)
{
DWORD intermediate = 0;
if (WriteFile(m_file_handle, (char const*)i->iov_base
, (DWORD)i->iov_len, &intermediate, 0) == FALSE)
{
ec = error_code(GetLastError(), get_system_category());
return -1;
}
ret += intermediate;
}
return ret;
}
int size = bufs_size(bufs, num_bufs);
// number of pages for the write. round up
int num_pages = (size + m_page_size - 1) / m_page_size;
// allocate array of FILE_SEGMENT_ELEMENT for WriteFileGather
FILE_SEGMENT_ELEMENT* segment_array = TORRENT_ALLOCA(FILE_SEGMENT_ELEMENT, num_pages + 1);
FILE_SEGMENT_ELEMENT* cur_seg = segment_array;
for (file::iovec_t const* i = bufs, *end(bufs + num_bufs); i < end; ++i)
{
for (int k = 0; k < i->iov_len; k += m_page_size)
{
cur_seg->Buffer = PtrToPtr64((((char*)i->iov_base) + k));
++cur_seg;
}
}
// terminate the array
cur_seg->Buffer = 0;
OVERLAPPED ol;
ol.Internal = 0;
ol.InternalHigh = 0;
ol.OffsetHigh = file_offset >> 32;
ol.Offset = file_offset & 0xffffffff;
ol.hEvent = CreateEvent(0, true, false, 0);
ret += size;
// if file_size is > 0, the file will be opened in unbuffered
// mode after the write completes, and truncate the file to
// file_size.
size_type file_size = 0;
if ((size & (m_page_size-1)) != 0)
{
// if size is not an even multiple, this must be the tail
// of the file. Write the whole page and then open a new
// file without FILE_FLAG_NO_BUFFERING and set the
// file size to file_offset + size
file_size = file_offset + size;
size = num_pages * m_page_size;
}
if (WriteFileGather(m_file_handle, segment_array, size, 0, &ol) == 0)
{
if (GetLastError() != ERROR_IO_PENDING)
{
TORRENT_ASSERT(GetLastError() != ERROR_BAD_ARGUMENTS);
ec = error_code(GetLastError(), get_system_category());
CloseHandle(ol.hEvent);
return -1;
}
DWORD tmp;
if (GetOverlappedResult(m_file_handle, &ol, &tmp, true) == 0)
{
ec = error_code(GetLastError(), get_system_category());
CloseHandle(ol.hEvent);
return -1;
}
if (tmp < ret) ret = tmp;
}
CloseHandle(ol.hEvent);
if (file_size > 0)
{
#if TORRENT_USE_WPATH
#define CreateFile_ CreateFileW
#else
#define CreateFile_ CreateFileA
#endif
HANDLE f = CreateFile_(m_path.c_str(), GENERIC_WRITE
, FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING
, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, 0);
if (f == INVALID_HANDLE_VALUE)
{
ec = error_code(GetLastError(), get_system_category());
return -1;
}
LARGE_INTEGER offs;
offs.QuadPart = file_size;
if (SetFilePointerEx(f, offs, &offs, FILE_BEGIN) == FALSE)
{
CloseHandle(f);
ec = error_code(GetLastError(), get_system_category());
return -1;
}
if (::SetEndOfFile(f) == FALSE)
{
ec = error_code(GetLastError(), get_system_category());
CloseHandle(f);
return -1;
}
CloseHandle(f);
}
return ret;
#else
size_type ret = lseek(m_fd, file_offset, SEEK_SET);
if (ret < 0)
{
ec = error_code(errno, get_posix_category());
return -1;
}
#if TORRENT_USE_WRITEV
#ifdef TORRENT_LINUX
bool aligned = false;
int size = 0;
// if we're not opened in no-buffer mode, we don't need alignment
if ((m_open_mode & no_buffer) == 0) aligned = true;
if (!aligned)
{
size = bufs_size(bufs, num_bufs);
if ((size & (size_alignment()-1)) == 0) aligned = true;
}
if (aligned)
#endif
{
ret = ::writev(m_fd, bufs, num_bufs);
if (ret < 0)
{
ec = error_code(errno, get_posix_category());
return -1;
}
return ret;
}
#ifdef TORRENT_LINUX
file::iovec_t* temp_bufs = TORRENT_ALLOCA(file::iovec_t, num_bufs);
memcpy(temp_bufs, bufs, sizeof(file::iovec_t) * num_bufs);
iovec_t& last = temp_bufs[num_bufs-1];
last.iov_len = (last.iov_len & ~(size_alignment()-1)) + size_alignment();
ret = ::writev(m_fd, temp_bufs, num_bufs);
if (ret < 0)
{
ec = error_code(errno, get_posix_category());
return -1;
}
if (ftruncate(m_fd, file_offset + size) < 0)
{
ec = error_code(errno, get_posix_category());
return -1;
}
return (std::min)(ret, size_type(size));
#endif // TORRENT_LINUX
#else // TORRENT_USE_WRITEV
ret = 0;
for (file::iovec_t const* i = bufs, *end(bufs + num_bufs); i < end; ++i)
{
int tmp = write(m_fd, i->iov_base, i->iov_len);
if (tmp < 0)
{
ec = error_code(errno, get_posix_category());
return -1;
}
ret += tmp;
if (tmp < i->iov_len) break;
}
return ret;
#endif // TORRENT_USE_WRITEV
#endif // TORRENT_WINDOWS
}
file_handle file_pool::open_file(void* st, std::string const& p
, int file_index, file_storage const& fs, int m, error_code& ec)
{
// potentially used to hold a reference to a file object that's
// about to be destructed. If we have such object we assign it to
// this member to be destructed after we release the mutex. On some
// operating systems (such as OSX) closing a file may take a long
// time. We don't want to hold the mutex for that.
file_handle defer_destruction;
mutex::scoped_lock l(m_mutex);
#if TORRENT_USE_ASSERTS
// we're not allowed to open a file
// from a deleted storage!
TORRENT_ASSERT(std::find(m_deleted_storages.begin(), m_deleted_storages.end(), std::make_pair(fs.name(), (void const*)&fs))
== m_deleted_storages.end());
#endif
TORRENT_ASSERT(st != 0);
TORRENT_ASSERT(is_complete(p));
TORRENT_ASSERT((m & file::rw_mask) == file::read_only
|| (m & file::rw_mask) == file::read_write);
file_set::iterator i = m_files.find(std::make_pair(st, file_index));
if (i != m_files.end())
{
lru_file_entry& e = i->second;
e.last_use = aux::time_now();
if (e.key != st && ((e.mode & file::rw_mask) != file::read_only
|| (m & file::rw_mask) != file::read_only))
{
// this means that another instance of the storage
// is using the exact same file.
ec = errors::file_collision;
return file_handle();
}
e.key = st;
// if we asked for a file in write mode,
// and the cached file is is not opened in
// write mode, re-open it
if ((((e.mode & file::rw_mask) != file::read_write)
&& ((m & file::rw_mask) == file::read_write))
|| (e.mode & file::random_access) != (m & file::random_access))
{
// close the file before we open it with
// the new read/write privilages, since windows may
// file opening a file twice. However, since there may
// be outstanding operations on it, we can't close the
// file, we can only delete our reference to it.
// if this is the only reference to the file, it will be closed
defer_destruction = e.file_ptr;
e.file_ptr = boost::make_shared<file>();
std::string full_path = fs.file_path(file_index, p);
if (!e.file_ptr->open(full_path, m, ec))
{
m_files.erase(i);
return file_handle();
}
#ifdef TORRENT_WINDOWS
if (m_low_prio_io)
set_low_priority(e.file_ptr);
#endif
TORRENT_ASSERT(e.file_ptr->is_open());
e.mode = m;
}
return e.file_ptr;
}
lru_file_entry e;
e.file_ptr = boost::make_shared<file>();
if (!e.file_ptr)
{
ec = error_code(ENOMEM, get_posix_category());
return e.file_ptr;
}
std::string full_path = fs.file_path(file_index, p);
if (!e.file_ptr->open(full_path, m, ec))
return file_handle();
#ifdef TORRENT_WINDOWS
if (m_low_prio_io)
set_low_priority(e.file_ptr);
#endif
e.mode = m;
e.key = st;
m_files.insert(std::make_pair(std::make_pair(st, file_index), e));
TORRENT_ASSERT(e.file_ptr->is_open());
file_handle file_ptr = e.file_ptr;
// the file is not in our cache
if ((int)m_files.size() >= m_size)
{
// the file cache is at its maximum size, close
// the least recently used (lru) file from it
remove_oldest(l);
}
return file_ptr;
}
boost::intrusive_ptr<file> file_pool::open_file(void* st, std::string const& p
, file_storage::iterator fe, file_storage const& fs, int m, error_code& ec)
{
TORRENT_ASSERT(st != 0);
TORRENT_ASSERT(is_complete(p));
TORRENT_ASSERT((m & file::rw_mask) == file::read_only
|| (m & file::rw_mask) == file::read_write);
mutex::scoped_lock l(m_mutex);
file_set::iterator i = m_files.find(std::make_pair(st, fs.file_index(*fe)));
if (i != m_files.end())
{
lru_file_entry& e = i->second;
e.last_use = time_now();
if (e.key != st && ((e.mode & file::rw_mask) != file::read_only
|| (m & file::rw_mask) != file::read_only))
{
// this means that another instance of the storage
// is using the exact same file.
#if BOOST_VERSION >= 103500
ec = errors::file_collision;
#endif
return boost::intrusive_ptr<file>();
}
e.key = st;
// if we asked for a file in write mode,
// and the cached file is is not opened in
// write mode, re-open it
if ((((e.mode & file::rw_mask) != file::read_write)
&& ((m & file::rw_mask) == file::read_write))
|| (e.mode & file::no_buffer) != (m & file::no_buffer)
|| (e.mode & file::random_access) != (m & file::random_access))
{
// close the file before we open it with
// the new read/write privilages
TORRENT_ASSERT(e.file_ptr->refcount() == 1);
#if TORRENT_CLOSE_MAY_BLOCK
mutex::scoped_lock l(m_closer_mutex);
m_queued_for_close.push_back(e.file_ptr);
l.unlock();
e.file_ptr = new file;
#else
e.file_ptr->close();
#endif
std::string full_path = combine_path(p, fs.file_path(*fe));
if (!e.file_ptr->open(full_path, m, ec))
{
m_files.erase(i);
return boost::intrusive_ptr<file>();
}
#ifdef TORRENT_WINDOWS
// file prio is supported on vista and up
#if _WIN32_WINNT >= 0x0600
if (m_low_prio_io)
{
// TODO: load this function dynamically from Kernel32.dll
FILE_IO_PRIORITY_HINT_INFO priorityHint;
priorityHint.PriorityHint = IoPriorityHintLow;
SetFileInformationByHandle(e.file_ptr->native_handle(),
FileIoPriorityHintInfo, &priorityHint, sizeof(PriorityHint));
}
#endif
#endif
TORRENT_ASSERT(e.file_ptr->is_open());
e.mode = m;
}
TORRENT_ASSERT((e.mode & file::no_buffer) == (m & file::no_buffer));
return e.file_ptr;
}
// the file is not in our cache
if ((int)m_files.size() >= m_size)
{
// the file cache is at its maximum size, close
// the least recently used (lru) file from it
remove_oldest();
}
lru_file_entry e;
e.file_ptr.reset(new (std::nothrow)file);
if (!e.file_ptr)
{
ec = error_code(ENOMEM, get_posix_category());
return e.file_ptr;
}
std::string full_path = combine_path(p, fs.file_path(*fe));
if (!e.file_ptr->open(full_path, m, ec))
return boost::intrusive_ptr<file>();
e.mode = m;
e.key = st;
m_files.insert(std::make_pair(std::make_pair(st, fs.file_index(*fe)), e));
TORRENT_ASSERT(e.file_ptr->is_open());
return e.file_ptr;
}
