transmission/libtransmission/torrent-metainfo.h

246 lines
6.9 KiB
C++

// This file Copyright © Mnemosyne LLC.
// It may be used under GPLv2 (SPDX: GPL-2.0-only), GPLv3 (SPDX: GPL-3.0-only),
// or any future license endorsed by Mnemosyne LLC.
// License text can be found in the licenses/ folder.
#pragma once
#include <cstdint> // uint32_t, uint64_t
#include <ctime>
#include <string>
#include <string_view>
#include <vector>
#include "libtransmission/transmission.h"
#include "libtransmission/block-info.h"
#include "libtransmission/magnet-metainfo.h"
#include "libtransmission/torrent-files.h"
#include "libtransmission/tr-macros.h"
struct tr_error;
struct tr_torrent_metainfo : public tr_magnet_metainfo
{
public:
[[nodiscard]] TR_CONSTEXPR20 auto empty() const noexcept
{
return std::empty(files_);
}
bool parse_benc(std::string_view benc, tr_error* error = nullptr);
// Helper function wrapper around parseBenc().
// If you're looping through several files, passing in a non-nullptr
// `contents` can reduce the number of memory allocations needed to
// load multiple files.
bool parse_torrent_file(std::string_view benc_filename, std::vector<char>* contents = nullptr, tr_error* error = nullptr);
// FILES
[[nodiscard]] constexpr auto const& files() const noexcept
{
return files_;
}
[[nodiscard]] TR_CONSTEXPR20 auto file_count() const noexcept
{
return files().fileCount();
}
[[nodiscard]] TR_CONSTEXPR20 auto file_size(tr_file_index_t i) const
{
return files().fileSize(i);
}
[[nodiscard]] TR_CONSTEXPR20 auto const& file_subpath(tr_file_index_t i) const
{
return files().path(i);
}
void set_file_subpath(tr_file_index_t i, std::string_view subpath)
{
files_.setPath(i, subpath);
}
/// BLOCK INFO
[[nodiscard]] constexpr auto const& block_info() const noexcept
{
return block_info_;
}
[[nodiscard]] constexpr auto block_count() const noexcept
{
return block_info().block_count();
}
[[nodiscard]] constexpr auto byte_loc(uint64_t nth_byte) const noexcept
{
return block_info().byte_loc(nth_byte);
}
[[nodiscard]] constexpr auto block_loc(tr_block_index_t block) const noexcept
{
return block_info().block_loc(block);
}
[[nodiscard]] constexpr auto piece_loc(tr_piece_index_t piece, uint32_t offset = 0, uint32_t length = 0) const noexcept
{
return block_info().piece_loc(piece, offset, length);
}
[[nodiscard]] constexpr auto block_size(tr_block_index_t block) const noexcept
{
return block_info().block_size(block);
}
[[nodiscard]] constexpr auto block_span_for_piece(tr_piece_index_t piece) const noexcept
{
return block_info().block_span_for_piece(piece);
}
[[nodiscard]] constexpr auto piece_count() const noexcept
{
return block_info().piece_count();
}
[[nodiscard]] constexpr auto piece_size() const noexcept
{
return block_info().piece_size();
}
[[nodiscard]] constexpr auto piece_size(tr_piece_index_t piece) const noexcept
{
return block_info().piece_size(piece);
}
[[nodiscard]] constexpr auto total_size() const noexcept
{
return block_info().total_size();
}
// OTHER PROPERTIES
[[nodiscard]] constexpr auto const& comment() const noexcept
{
return comment_;
}
[[nodiscard]] constexpr auto const& creator() const noexcept
{
return creator_;
}
[[nodiscard]] constexpr auto const& source() const noexcept
{
return source_;
}
[[nodiscard]] constexpr auto is_private() const noexcept
{
return is_private_;
}
[[nodiscard]] TR_CONSTEXPR20 tr_sha1_digest_t const& piece_hash(tr_piece_index_t piece) const
{
return pieces_[piece];
}
[[nodiscard]] TR_CONSTEXPR20 bool has_v1_metadata() const noexcept
{
// need 'pieces' field and 'files' or 'length'
// TODO check for 'files' or 'length'
return !std::empty(pieces_);
}
[[nodiscard]] constexpr bool has_v2_metadata() const noexcept
{
return is_v2_;
}
[[nodiscard]] constexpr auto const& date_created() const noexcept
{
return date_created_;
}
[[nodiscard]] constexpr auto info_dict_size() const noexcept
{
return info_dict_size_;
}
[[nodiscard]] constexpr auto info_dict_offset() const noexcept
{
return info_dict_offset_;
}
[[nodiscard]] constexpr auto pieces_offset() const noexcept
{
return pieces_offset_;
}
// UTILS
[[nodiscard]] auto torrent_file(std::string_view torrent_dir) const
{
return make_filename(torrent_dir, name(), info_hash_string(), BasenameFormat::Hash, ".torrent");
}
[[nodiscard]] auto magnet_file(std::string_view torrent_dir) const
{
return make_filename(torrent_dir, name(), info_hash_string(), BasenameFormat::Hash, ".magnet");
}
[[nodiscard]] auto resume_file(std::string_view resume_dir) const
{
return make_filename(resume_dir, name(), info_hash_string(), BasenameFormat::Hash, ".resume");
}
static bool migrate_file(
std::string_view dirname,
std::string_view name,
std::string_view info_hash_string,
std::string_view suffix);
static void remove_file(
std::string_view dirname,
std::string_view name,
std::string_view info_hash_string,
std::string_view suffix);
private:
friend struct MetainfoHandler;
static bool parse_impl(tr_torrent_metainfo& setme, std::string_view benc, tr_error* error);
static std::string fix_webseed_url(tr_torrent_metainfo const& tm, std::string_view url);
enum class BasenameFormat
{
Hash,
NameAndPartialHash
};
[[nodiscard]] static std::string make_filename(
std::string_view dirname,
std::string_view name,
std::string_view info_hash_string,
BasenameFormat format,
std::string_view suffix);
[[nodiscard]] auto make_filename(std::string_view dirname, BasenameFormat format, std::string_view suffix) const
{
return make_filename(dirname, name(), info_hash_string(), format, suffix);
}
tr_block_info block_info_ = tr_block_info{ 0, 0 };
tr_torrent_files files_;
std::vector<tr_sha1_digest_t> pieces_;
std::string comment_;
std::string creator_;
std::string source_;
time_t date_created_ = 0;
// Offset + size of the bencoded info dict subset of the bencoded data.
// Used when loading pieces of it to sent to magnet peers.
// See http://bittorrent.org/beps/bep_0009.html
uint64_t info_dict_size_ = 0;
uint64_t info_dict_offset_ = 0;
// Offset of the bencoded 'pieces' checksums subset of the bencoded data.
// Used when loading piece checksums on demand.
uint64_t pieces_offset_ = 0;
bool has_magnet_info_hash_ = false;
bool is_private_ = false;
bool is_v2_ = false;
};