examples

Except for the example programs in this manual, there's also a bigger example of a (little bit) more complete client, client_test. There are separate instructions for how to use it here if you'd like to try it.

#include<cstdlib> #include"libtorrent/entry.hpp" #include"libtorrent/bencode.hpp" #include"libtorrent/session.hpp" #include"libtorrent/torrent_info.hpp"#include<iostream>intmain(intargc,char*argv[])try{if(argc!=2){std::cerr<<"usage: ./simple_client torrent-file\n""to stop the client, press return.\n";return1;}lt::sessions;lt::add_torrent_paramsp;p.save_path=".";p.ti=std::make_shared<lt::torrent_info>(argv[1]);s.add_torrent(p);// wait for the user to end chara;intret=std::scanf("%c\n",&a);(void)ret;// ignore return0;}catch(std::exceptionconst&e){std::cerr<<"ERROR: "<<e.what()<<"\n";}

#include"libtorrent/entry.hpp" #include"libtorrent/bencode.hpp" #include"libtorrent/torrent_info.hpp" #include"libtorrent/create_torrent.hpp"#include<functional> #include<cstdio> #include<sstream> #include<fstream> #include<iostream>#ifdef TORRENT_WINDOWS #include<direct.h> // for _getcwd #endif namespace{usingnamespacestd::placeholders;std::vector<char>load_file(std::stringconst&filename){std::fstreamin;in.exceptions(std::ifstream::failbit);in.open(filename.c_str(),std::ios_base::in|std::ios_base::binary);in.seekg(0,std::ios_base::end);size_tconstsize=size_t(in.tellg());in.seekg(0,std::ios_base::beg);std::vector<char>ret(size);in.read(ret.data(),int(ret.size()));returnret;}std::stringbranch_path(std::stringconst&f){if(f.empty())returnf;#ifdef TORRENT_WINDOWS if(f=="\\\\")return"";#endif if(f=="/")return"";autolen=f.size();// if the last character is / or \ ignore it if(f[len-1]=='/'||f[len-1]=='\\')--len;while(len>0){--len;if(f[len]=='/'||f[len]=='\\')break;}if(f[len]=='/'||f[len]=='\\')++len;returnstd::string(f.c_str(),len);}// do not include files and folders whose // name starts with a . boolfile_filter(std::stringconst&f){if(f.empty())returnfalse;charconst*first=f.c_str();charconst*sep=strrchr(first,'/');#if defined(TORRENT_WINDOWS) || defined(TORRENT_OS2) charconst*altsep=strrchr(first,'\\');if(sep==nullptr||altsep>sep)sep=altsep;#endif // if there is no parent path, just set 'sep' // to point to the filename. // if there is a parent path, skip the '/' character if(sep==nullptr)sep=first;else++sep;// return false if the first character of the filename is a . if(sep[0]=='.')returnfalse;std::cerr<<f<<"\n";returntrue;}[[noreturn]]voidprint_usage(){std::cerr<<R"(usage: make_torrent FILE [OPTIONS] Generates a torrent file from the specified file or directory and writes it to standard out OPTIONS: -w url adds a web seed to the torrent with the specified url -t url adds the specified tracker to the torrent. For multiple trackers, specify more -t options. Specify a dash character "-" as a tracker to indicate the following trackers should be in a higher tier. -c comment sets the comment to the specified string -C creator sets the created-by field to the specified string -s bytes specifies a piece size for the torrent This has to be a power of 2, minimum 16kiB -l Don't follow symlinks, instead encode them as links in the torrent file -o file specifies the output filename of the torrent file If this is not specified, the torrent file is printed to the standard out, except on windows where the filename defaults to a.torrent -r file add root certificate to the torrent, to verify the HTTPS tracker -S info-hash add a similar torrent by info-hash. The similar torrent is expected to share some files with this one -L collection add a collection name to this torrent. Other torrents in the same collection is expected to share files with this one. -2 Only generate V2 metadata -T Include file timestamps in the .torrent file. )";std::exit(1);}}// anonymous namespace intmain(intargc_,charconst*argv_[])try{lt::span<charconst*>args(argv_,argc_);std::stringcreator_str="libtorrent";std::stringcomment_str;if(args.size()<2)print_usage();std::vector<std::string>web_seeds;std::vector<std::string>trackers;std::vector<std::string>collections;std::vector<lt::sha1_hash>similar;intpiece_size=0;lt::create_flags_tflags={};std::stringroot_cert;std::stringoutfile;#ifdef TORRENT_WINDOWS // don't ever write binary data to the console on windows // it will just be interpreted as text and corrupted outfile="a.torrent";#endif std::stringfull_path=args[1];args=args.subspan(2);for(;!args.empty();args=args.subspan(1)){if(args[0][0]!='-')print_usage();charconstflag=args[0][1];switch(flag){case'l':flags|=lt::create_torrent::symlinks;continue;case'2':flags|=lt::create_torrent::v2_only;continue;case'T':flags|=lt::create_torrent::modification_time;continue;}if(args.size()<2)print_usage();switch(flag){case'w':web_seeds.push_back(args[1]);break;case't':trackers.push_back(args[1]);break;case's':piece_size=atoi(args[1]);break;case'o':outfile=args[1];break;case'C':creator_str=args[1];break;case'c':comment_str=args[1];break;case'r':root_cert=args[1];break;case'L':collections.push_back(args[1]);break;case'S':{if(strlen(args[1])!=40){std::cerr<<"invalid info-hash for -S. ""Expected 40 hex characters\n";print_usage();}std::stringstreamhash(args[1]);lt::sha1_hashih;hash>>ih;if(hash.fail()){std::cerr<<"invalid info-hash for -S\n";print_usage();}similar.push_back(ih);break;}default:print_usage();}args=args.subspan(1);}lt::file_storagefs;#ifdef TORRENT_WINDOWS if(full_path[1]!=':')#else if(full_path[0]!='/')#endif {charcwd[2048];#ifdef TORRENT_WINDOWS #define getcwd_ _getcwd #else #define getcwd_ getcwd #endif charconst*ret=getcwd_(cwd,sizeof(cwd));if(ret==nullptr){std::cerr<<"failed to get current working directory: "<<strerror(errno)<<"\n";return1;}#undef getcwd_ #ifdef TORRENT_WINDOWS full_path=cwd+("\\"+full_path);#else full_path=cwd+("/"+full_path);#endif }lt::add_files(fs,full_path,file_filter,flags);if(fs.num_files()==0){std::cerr<<"no files specified.\n";return1;}lt::create_torrentt(fs,piece_size,flags);inttier=0;for(std::stringconst&tr:trackers){if(tr=="-")++tier;elset.add_tracker(tr,tier);}for(std::stringconst&ws:web_seeds)t.add_url_seed(ws);for(std::stringconst&c:collections)t.add_collection(c);for(lt::sha1_hashconst&s:similar)t.add_similar_torrent(s);autoconstnum=t.num_pieces();lt::set_piece_hashes(t,branch_path(full_path),[num](lt::piece_index_tconstp){std::cerr<<"\r"<<p<<"/"<<num;});std::cerr<<"\n";t.set_creator(creator_str.c_str());if(!comment_str.empty()){t.set_comment(comment_str.c_str());}if(!root_cert.empty()){std::vector<char>constpem=load_file(root_cert);t.set_root_cert(std::string(&pem[0],pem.size()));}// create the torrent and print it to stdout std::vector<char>torrent;lt::bencode(back_inserter(torrent),t.generate());if(!outfile.empty()){std::fstreamout;out.exceptions(std::ifstream::failbit);out.open(outfile.c_str(),std::ios_base::out|std::ios_base::binary);out.write(torrent.data(),int(torrent.size()));}else{std::cout.write(torrent.data(),int(torrent.size()));}return0;}catch(std::exception&e){std::cerr<<"ERROR: "<<e.what()<<"\n";return1;}

#include<cstdio> // for snprintf #include<cinttypes> // for PRId64 et.al. #include<fstream> #include<iostream>#include"libtorrent/entry.hpp" #include"libtorrent/bencode.hpp" #include"libtorrent/load_torrent.hpp" #include"libtorrent/bdecode.hpp" #include"libtorrent/magnet_uri.hpp" #include"libtorrent/span.hpp"namespace{[[noreturn]]voidprint_usage(){std::cerr<<R"(usage: dump_torrent torrent-file [options] OPTIONS: --items-limit <count> set the upper limit of the number of bencode items in the torrent file. --depth-limit <count> set the recursion limit in the bdecoder --show-padfiles show pad files in file list --max-pieces <count> set the upper limit on the number of pieces to load in the torrent. --max-size <size in MiB> reject files larger than this size limit )";std::exit(1);}}intmain(intargc,charconst*argv[])try{lt::span<charconst*>args(argv,argc);// strip executable name args=args.subspan(1);lt::load_torrent_limitscfg;boolshow_pad=false;if(args.empty())print_usage();charconst*filename=args[0];args=args.subspan(1);usingnamespacelt::literals;while(!args.empty()){if(args[0]=="--items-limit"_sv&&args.size()>1){cfg.max_decode_tokens=atoi(args[1]);args=args.subspan(2);}elseif(args[0]=="--depth-limit"_sv&&args.size()>1){cfg.max_decode_depth=atoi(args[1]);args=args.subspan(2);}elseif(args[0]=="--max-pieces"_sv&&args.size()>1){cfg.max_pieces=atoi(args[1]);args=args.subspan(2);}elseif(args[0]=="--max-size"_sv&&args.size()>1){cfg.max_buffer_size=atoi(args[1])*1024*1024;args=args.subspan(2);}elseif(args[0]=="--show-padfiles"_sv){show_pad=true;args=args.subspan(1);}else{std::cerr<<"unknown option: "<<args[0]<<"\n";print_usage();}}lt::add_torrent_paramsconstatp=lt::load_torrent_file(filename,cfg);// print info about torrent if(!atp.dht_nodes.empty()){std::printf("nodes:\n");for(autoconst&i:atp.dht_nodes)std::printf("%s: %d\n",i.first.c_str(),i.second);}if(!atp.trackers.empty()){puts("trackers:\n");autotier_it=atp.tracker_tiers.begin();inttier=0;for(autoconst&i:atp.trackers){if(tier_it!=atp.tracker_tiers.end()){tier=*tier_it;++tier_it;}std::printf("%2d: %s\n",tier,i.c_str());}}std::stringstreamih;ih<<atp.info_hashes.v1;if(atp.info_hashes.has_v2())ih<<", "<<atp.info_hashes.v2;std::printf("number of pieces: %d\n""piece length: %d\n""info hash: %s\n""comment: %s\n""created by: %s\n""magnet link: %s\n""name: %s\n""number of files: %d\n""files:\n",atp.ti->num_pieces(),atp.ti->piece_length(),ih.str().c_str(),atp.ti->comment().c_str(),atp.ti->creator().c_str(),make_magnet_uri(atp).c_str(),atp.name.c_str(),atp.ti->num_files());lt::file_storageconst&st=atp.ti->files();for(autoconsti:st.file_range()){autoconstfirst=st.map_file(i,0,0).piece;autoconstlast=st.map_file(i,std::max(std::int64_t(st.file_size(i))-1,std::int64_t(0)),0).piece;autoconstflags=st.file_flags(i);if((flags&lt::file_storage::flag_pad_file)&&!show_pad)continue;std::stringstreamfile_root;if(!st.root(i).is_all_zeros())file_root<<st.root(i);std::printf(" %8"PRIx64" %11"PRId64" %c%c%c%c [ %5d, %5d ] %7u %s %s %s%s\n",st.file_offset(i),st.file_size(i),((flags&lt::file_storage::flag_pad_file)?'p':'-'),((flags&lt::file_storage::flag_executable)?'x':'-'),((flags&lt::file_storage::flag_hidden)?'h':'-'),((flags&lt::file_storage::flag_symlink)?'l':'-'),static_cast<int>(first),static_cast<int>(last),std::uint32_t(st.mtime(i)),file_root.str().c_str(),st.file_path(i).c_str(),(flags&lt::file_storage::flag_symlink)?"-> ":"",(flags&lt::file_storage::flag_symlink)?st.symlink(i).c_str():"");}std::printf("web seeds:\n");for(autoconst&ws:atp.url_seeds)std::printf("%s\n",ws.c_str());return0;}catch(std::exceptionconst&e){std::cerr<<"ERROR: "<<e.what()<<"\n";}