Ton

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/*
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    This file is part of TON Blockchain Library.
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    TON Blockchain Library is free software: you can redistribute it and/or modify
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    it under the terms of the GNU Lesser General Public License as published by
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    the Free Software Foundation, either version 2 of the License, or
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    (at your option) any later version.
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    TON Blockchain Library is distributed in the hope that it will be useful,
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    but WITHOUT ANY WARRANTY; without even the implied warranty of
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    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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    GNU Lesser General Public License for more details.
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    You should have received a copy of the GNU Lesser General Public License
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    along with TON Blockchain Library.  If not, see <http://www.gnu.org/licenses/>.
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    Copyright 2017-2020 Telegram Systems LLP
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*/
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#include "TorrentInfo.h"
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#include "vm/cells/CellString.h"
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#include "vm/cellslice.h"
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#include "td/utils/misc.h"
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namespace ton {
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bool TorrentInfo::pack(vm::CellBuilder &cb) const {
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  return cb.store_long_bool(piece_size, 32) && cb.store_long_bool(file_size, 64) && cb.store_bits_bool(root_hash) &&
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         cb.store_long_bool(header_size, 64) && cb.store_bits_bool(header_hash) &&
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         vm::CellText::store(cb, description).is_ok();
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}
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bool TorrentInfo::unpack(vm::CellSlice &cs) {
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  return cs.fetch_uint_to(32, piece_size) && cs.fetch_uint_to(64, file_size) && cs.fetch_bits_to(root_hash) &&
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         cs.fetch_uint_to(64, header_size) && cs.fetch_bits_to(header_hash) && vm::CellText::fetch_to(cs, description);
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}
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td::Bits256 TorrentInfo::get_hash() const {
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  return as_cell()->get_hash().bits();
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}
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void TorrentInfo::init_cell() {
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  vm::CellBuilder cb;
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  CHECK(pack(cb));
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  cell_ = cb.finalize();
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}
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td::Ref<vm::Cell> TorrentInfo::as_cell() const {
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  CHECK(cell_.not_null())
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  return cell_;
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}
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td::uint64 TorrentInfo::pieces_count() const {
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  return (file_size + piece_size - 1) / piece_size;
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}
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TorrentInfo::PieceInfo TorrentInfo::get_piece_info(td::uint64 piece_i) const {
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  PieceInfo info;
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  info.offset = piece_size * piece_i;
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  CHECK(info.offset < file_size);
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  info.size = td::min(static_cast<td::uint64>(piece_size), file_size - info.offset);
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  return info;
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}
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td::Status TorrentInfo::validate() const {
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  if (piece_size == 0) {
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    return td::Status::Error("Piece size is 0");
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  }
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  if (header_size > file_size) {
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    return td::Status::Error("Header is too big");
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  }
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  if (description.size() > 1024) {
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    return td::Status::Error("Description is too long");
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  }
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  if (piece_size > (1 << 23)) {
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    return td::Status::Error("Piece size is too big");
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  }
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  if (pieces_count() >= (1ULL << 31)) {
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    return td::Status::Error("Too many pieces");
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  }
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  return td::Status::OK();
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}
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}  // namespace ton
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