Monero C++ Library

This project is a library for working with Monero wallets in C++ by wrapping Monero Core's C++ wallet, wallet2.

In addition, this project conforms to an API specification intended to be intuitive, robust, and for long-term use in the Monero project.

This library may be used to build Monero-related applications, such as GUIs, libraries in other languages (e.g. monero-java), or a compliant REST/JSON-RPC API.

Main Features

• Manage Monero wallets which connect to a daemon
• Query wallet transactions, transfers, and outputs by their many attributes
• Receive notifications as a wallet is synchronized, when blocks are added to the chain, or when the wallet sends or receives transfers

Sample Code

This code introduces the API. See the specification PDF for full details.

  // create a wallet from a mnemonic phrase
  string mnemonic = "hefty value later extra artistic firm radar yodel talent future fungal nutshell because sanity awesome nail unjustly rage unafraid cedar delayed thumbs comb custom sanity";
  monero_wallet* wallet_restored = monero_wallet::create_wallet_from_mnemonic(
      "MyWalletRestored",                               // wallet path and name
      "supersecretpassword123",                         // wallet password
      monero_network_type::STAGENET,                    // network type
      mnemonic,                                         // mnemonic phrase
      monero_rpc_connection("http://localhost:38081"),  // daemon connection
      380104                                            // restore height
  );

  // sync the wallet
  wallet_restored->sync();          // one time synchronous sync
  wallet_restored->start_syncing();  // continuously sync as an asynchronous thread in the background

  // get balance, account, subaddresses
  string primary_address = wallet_restored->get_primary_address();
  uint64_t balance = wallet_restored->get_balance();    // can specify account and subaddress indices
  monero_account account = wallet_restored->get_account(1, true);     // get account with subaddresses
  uint64_t unlocked_account_balance = account.m_unlocked_balance.get(); // get boost::optional value

  // query a transaction by id
  monero_tx_query tx_query;
  tx_query.m_id = "3276252c5a545b90c8e147fcde45d3e1917726470a8f7d4c8977b527a44dfd15";
  shared_ptr<monero_tx_wallet> tx = wallet_restored->get_txs(tx_query)[0];
  for (const shared_ptr<monero_incoming_transfer> in_transfer : tx->m_incoming_transfers) {
    uint64_t in_amount = in_transfer->m_amount.get();
    int account_index = in_transfer->m_account_index.get();
  }

  // query incoming transfers to account 1
  monero_transfer_query transfer_query;
  transfer_query.m_is_incoming = true;
  transfer_query.m_account_index = 1;
  vector<shared_ptr<monero_transfer>> transfers = wallet_restored->get_transfers(transfer_query);

  // query unspent outputs
  monero_output_query output_query;
  output_query.m_is_spent = false;
  vector<shared_ptr<monero_output_wallet>> outputs = wallet_restored->get_outputs(output_query);

  // create a new wallet with a random mnemonic phrase
  monero_wallet* wallet_random = monero_wallet::create_wallet_random(
      "MyWalletRandom",                                 // wallet path and name
      "supersecretpassword123",                         // wallet password
      monero_network_type::STAGENET,                    // network type
      monero_rpc_connection("http://localhost:38081"),  // daemon connection
      "English"
  );

  // continuously synchronize the wallet
  wallet_random->start_syncing();

  // get wallet info
  string random_mnemonic = wallet_random->get_mnemonic();
  string address = wallet_random->get_primary_address();
  uint64_t height = wallet_random->get_height();
  bool is_synced = wallet_random->is_synced();

  // be notified when the wallet receives funds
  struct : monero_wallet_listener {
    void on_output_received(const monero_output_wallet& output) {
      cout << "Wallet received funds!" << endl;
      int account_index = output.m_account_index.get();
      int subaddress_index = output.m_subaddress_index.get();
      shared_ptr<monero_key_image> key_image = output.m_key_image.get();
    }
  } my_listener;
  wallet_random->set_listener(my_listener);

  // TODO: define wallet send convenience methods
//  // send funds from the restored wallet to the random wallet
//  monero_tx_wallet sent_tx = wallet_restored->send(0, wallet_random->get_address(1, 0), 50000);
//  boolean in_pool = sent_tx.in_tx_pool();  // true

  // create a request to send funds to multiple destinations in the random wallet
  monero_send_request send_request = monero_send_request();
  send_request.m_account_index = 1;                // withdraw funds from this account
  send_request.m_subaddress_indices = vector<uint32_t>();
  send_request.m_subaddress_indices.push_back(0);
  send_request.m_subaddress_indices.push_back(1);  // withdraw funds from these subaddresses within the account
  send_request.m_priority = monero_send_priority::UNIMPORTANT;  // no rush
  vector<shared_ptr<monero_destination>> destinations;  // specify the recipients and their amounts
//  destinations.push_back(make_shared<monero_destination>(wallet_random->get_address(1, 0), 50000)); // TODO: destination constructor
//  destinations.push_back(make_shared<monero_destination>(wallet_random->get_address(2, 0), 50000));
  send_request.m_destinations = destinations;

  // TODO: define wallet send convenience methods
//  // create the transaction, confirm with the user, and relay to the network
//  shared_ptr<monero_tx_wallet> created_tx = wallet_restored->create_tx(send_request);
//  uint64_t fee = created_tx->fee.get();   // "Are you sure you want to send ...?"
//  wallet_restored->relay_tx(created_tx);  // submit the transaction to the Monero network which will notify the recipient wallet

Building a Dynamic / Shared Library

The source code in this project may be built as a dynamic or shared library for use on a target platform (e.g. Linux, Mac, Windows, etc). For example, the associated Java library depends on a dynamic library built from this project to support a wallet using Java JNI.

Build Steps

1. Setup Boost
   1. Download and extract the boost 1.69.0 source code zip from https://www.boost.org/users/download/ to ./external/boost-sdk/.
   2. cd ./external/boost-sdk/
   3. ./bootstraph.sh
   4. ./b2
   5. Copy .a files from ./external/boost-sdk/bin.v2/libs/*/link-static/* to ./external-libs/boost according to CMakeLists.txt.
2. Setup OpenSSL
   1. Download and extract the latest OpenSSL source code zip from https://github.com/openssl/openssl to ./external/openssl-sdk/.
   2. Build for your system.
      Mac: installed through boost at /usr/local/opt/openssl/lib
   3. Copy libcrypto.a and libssl.a ./external-libs/openssl.
3. Setup Monero Core
   1. Initialize submodules: git submodule update --init --recursive
   2. cd ./submodules/monero-core
   3. Modify CMakeLists.txt: option(BUILD_GUI_DEPS "Build GUI dependencies." ON).
   4. Build twice to create libwallet_merged.a in addition to other .a libraries: make release-static -j8.
   5. Copy .a files from ./submodules/monero-core/build/release/* to ./external-libs/monero-core according to CMakeLists.txt.
4. Setup hidapi
   1. Download the latest hidapi source code from https://github.com/signal11/hidapi.
   2. Build hidapi for your system.
      Mac requires autoreconf: brew install automake
   3. Copy libhidapi.a to ./external-libs/hidapi.
5. Setup libsodium
   1. Build libsodium for your system.
   2. Copy libsodium.a to ./external-libs/libsodium.
      Mac: installed through homebrew at /usr/local/Cellar/libsodium/1.0.17/lib/libsodium.a
6. Build libmonero-cpp.dylib to ./build: ./bin/build-libmonero-cpp.sh.

These build steps aspire to be automated further.

See Also

Java reference implementation

JavaScript reference implementation

License

This project is licensed under MIT.

Donate

Donations are gratefully accepted. Thank you for your support!

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