Merge pull request #1411 from evoskuil/master

Add settings, checkpoint.equals, uint256_t serialize, chain_state.cumulative_work.

include/bitcoin/system/chain/chain_state.hpp

@@ -173,6 +173,7 @@ class BC_API chain_state
     /// Properties.
     chain::context context() const NOEXCEPT;
     const hash_digest& hash() const NOEXCEPT;
+    const uint256_t& cumulative_work() const NOEXCEPT;
     uint32_t minimum_block_version() const NOEXCEPT;
     uint32_t work_required() const NOEXCEPT;
     uint32_t timestamp() const NOEXCEPT;
@@ -237,6 +238,7 @@ class BC_API chain_state
     const activations active_;
     const uint32_t work_required_;
     const uint32_t median_time_past_;
+    const uint256_t cumulative_work_;
 };
 
 } // namespace chain

include/bitcoin/system/chain/checkpoint.hpp

@@ -78,6 +78,11 @@ class BC_API checkpoint
     ////bool to_string(std::ostream& stream) const NOEXCEPT;
     ////bool to_string(writer& sink) const NOEXCEPT;
 
+    /// Methods.
+    /// -----------------------------------------------------------------------
+
+    bool equals(const hash_digest& hash, size_t height) const NOEXCEPT;
+
     /// Properties.
     /// -----------------------------------------------------------------------
 

include/bitcoin/system/config/hash256.hpp

@@ -42,6 +42,7 @@ class BC_API hash256 final
     std::string to_string() const NOEXCEPT;
 
     operator const hash_digest&() const NOEXCEPT;
+    operator uint256_t() const NOEXCEPT;
 
     friend std::istream& operator>>(std::istream& stream,
         hash256& argument) THROWS;

include/bitcoin/system/settings.hpp

@@ -125,6 +125,12 @@ class BC_API settings
 
     /// This cannot be reactivated in a future branch due to window expiration.
     chain::checkpoint bip9_bit1_active_checkpoint{};
+
+    /// A block that is presumed to be valid but not required to be present.
+    chain::checkpoint milestone{};
+
+    /// The minimum work for any branch to be considered valid.
+    config::hash256 minimum_work{};
 };
 
 } // namespace system

src/chain/chain_state.cpp

@@ -584,13 +584,15 @@ chain_state::data chain_state::to_pool(const chain_state& top,
 
 // Top to pool.
 // This generates a state for the pool above the presumed top block state.
+// Work is not acculuated for a pool state.
 chain_state::chain_state(const chain_state& top,
     const system::settings& settings) NOEXCEPT
   : data_(to_pool(top, settings)),
     forks_(top.forks_),
     active_(activation(data_, forks_, settings)),
     work_required_(work_required(data_, forks_, settings)),
-    median_time_past_(median_time_past(data_, forks_))
+    median_time_past_(median_time_past(data_, forks_)),
+    cumulative_work_(top.cumulative_work())
 {
 }
 
@@ -627,7 +629,8 @@ chain_state::chain_state(const chain_state& pool, const block& block,
     forks_(pool.forks_),
     active_(activation(data_, forks_, settings)),
     work_required_(work_required(data_, forks_, settings)),
-    median_time_past_(median_time_past(data_, forks_))
+    median_time_past_(median_time_past(data_, forks_)),
+    cumulative_work_(pool.cumulative_work() + block.header().proof())
 {
 }
 
@@ -665,7 +668,8 @@ chain_state::chain_state(const chain_state& parent, const header& header,
     forks_(parent.forks_),
     active_(activation(data_, forks_, settings)),
     work_required_(work_required(data_, forks_, settings)),
-    median_time_past_(median_time_past(data_, forks_))
+    median_time_past_(median_time_past(data_, forks_)),
+    cumulative_work_(parent.cumulative_work() + header.proof())
 {
 }
 
@@ -683,11 +687,29 @@ chain_state::chain_state(data&& values,
 // Properties.
 // ----------------------------------------------------------------------------
 
+chain::context chain_state::context() const NOEXCEPT
+{
+    return
+    {
+        forks(),
+        timestamp(),
+        median_time_past(),
+        possible_narrow_cast<uint32_t>(height()),
+        minimum_block_version(),
+        work_required()
+    };
+}
+
 const hash_digest& chain_state::hash() const NOEXCEPT
 {
     return data_.hash;
 }
 
+const uint256_t& chain_state::cumulative_work() const NOEXCEPT
+{
+    return cumulative_work_;
+}
+
 uint32_t chain_state::minimum_block_version() const NOEXCEPT
 {
     return active_.minimum_block_version;
@@ -720,19 +742,6 @@ size_t chain_state::height() const NOEXCEPT
     return data_.height;
 }
 
-chain::context chain_state::context() const NOEXCEPT
-{
-    return
-    {
-        forks(),
-        timestamp(),
-        median_time_past(),
-        possible_narrow_cast<uint32_t>(height()),
-        minimum_block_version(),
-        work_required()
-    };
-}
-
 } // namespace chain
 } // namespace system
 } // namespace libbitcoin

src/chain/checkpoint.cpp

@@ -110,6 +110,12 @@ checkpoint checkpoint::from_string(const std::string& hash,
     return { std::move(digest), height, true };
 }
 
+// functional equality
+bool checkpoint::equals(const hash_digest& hash, size_t height) const NOEXCEPT
+{
+    return this->hash() == hash && this->height() == height;
+}
+
 // Operators.
 // ----------------------------------------------------------------------------
 
@@ -120,7 +126,7 @@ bool operator<(const checkpoint& left, const checkpoint& right) NOEXCEPT
 
 bool operator==(const checkpoint& left, const checkpoint& right) NOEXCEPT
 {
-    return left.hash() == right.hash() && left.height() == right.height();
+    return left.equals(right.hash(), right.height());
 }
 
 bool operator!=(const checkpoint& left, const checkpoint& right) NOEXCEPT

src/config/hash256.cpp

@@ -61,6 +61,11 @@ hash256::operator const hash_digest&() const NOEXCEPT
     return value_;
 }
 
+hash256::operator uint256_t() const NOEXCEPT
+{
+    return to_uintx(value_);
+}
+
 std::istream& operator>>(std::istream& stream, hash256& argument) THROWS
 {
     std::string base16;

src/settings.cpp

@@ -137,6 +137,8 @@ settings::settings(chain::selection context) NOEXCEPT
                 { "000000002dd5588a74784eaa7ab0507a18ad16a236e7b1ce69f00d7ddfb5d0a6", 33333 },
                 { "0000000069e244f73d78e8fd29ba2fd2ed618bd6fa2ee92559f542fdb26e7c1d", 11111 }
             };
+            milestone = { "00000000000000000001a0a448d6cf2546b06801389cc030b2b18c6491266815", 804000 };
+            minimum_work = base16_hash("000000000000000000000000000000000000000052b2559353df4117b7348b64");
             break;
         }
 
@@ -195,6 +197,8 @@ settings::settings(chain::selection context) NOEXCEPT
             {
                 { "000000002a936ca763904c3c35fce2f3556c559c0214345d31b1bcebf76acb70", 546 }
             };
+            milestone = { "0000000000000093bcb68c03a9a168ae252572d348a2eaeba2cdf9231d73206f", 2500000 };
+            minimum_work = base16_hash("000000000000000000000000000000000000000000000b6a51f415a67c0da307");
             break;
         }
 
@@ -252,6 +256,8 @@ settings::settings(chain::selection context) NOEXCEPT
             bip9_bit0_active_checkpoint = { "0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206", 0 };
             bip9_bit1_active_checkpoint = { "0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206", 0 };
             checkpoints = {};
+            milestone = { "0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206", 0 };
+            minimum_work = base16_hash("0000000000000000000000000000000000000000000000000000000000000000");
             break;
         }
 

test/settings.cpp

@@ -96,6 +96,9 @@ BOOST_AUTO_TEST_CASE(settings__construct__mainnet_context__expected)
     BOOST_REQUIRE_EQUAL(configuration.bitcoin_to_satoshi(1), 100000000u);
     BOOST_REQUIRE_EQUAL(configuration.max_money(), 2099999997690000u);
     BOOST_REQUIRE_EQUAL(configuration.checkpoints, checkpoints);
+    BOOST_REQUIRE_EQUAL(configuration.minimum_work, to_uintx(base16_hash("000000000000000000000000000000000000000052b2559353df4117b7348b64")));
+    const chain::checkpoint milestone("00000000000000000001a0a448d6cf2546b06801389cc030b2b18c6491266815", 804000u);
+    BOOST_REQUIRE_EQUAL(configuration.milestone, milestone);
 }
 
 BOOST_AUTO_TEST_CASE(settings__construct__testnet_context__expected)
@@ -138,6 +141,9 @@ BOOST_AUTO_TEST_CASE(settings__construct__testnet_context__expected)
     BOOST_REQUIRE_EQUAL(configuration.bitcoin_to_satoshi(1), 100000000u);
     BOOST_REQUIRE_EQUAL(configuration.max_money(), 2099999997690000u);
     BOOST_REQUIRE_EQUAL(configuration.checkpoints, checkpoints);
+    BOOST_REQUIRE_EQUAL(configuration.minimum_work, to_uintx(base16_hash("000000000000000000000000000000000000000000000b6a51f415a67c0da307")));
+    const chain::checkpoint milestone("0000000000000093bcb68c03a9a168ae252572d348a2eaeba2cdf9231d73206f", 2500000u);
+    BOOST_REQUIRE_EQUAL(configuration.milestone, milestone);
 }
 
 BOOST_AUTO_TEST_CASE(settings__construct__regtest_context__expected)
@@ -171,6 +177,8 @@ BOOST_AUTO_TEST_CASE(settings__construct__regtest_context__expected)
     BOOST_REQUIRE_EQUAL(configuration.bitcoin_to_satoshi(1), 100000000u);
     BOOST_REQUIRE_EQUAL(configuration.max_money(), 1499999998350u);
     BOOST_REQUIRE(configuration.checkpoints.empty());
+    BOOST_REQUIRE_EQUAL(configuration.minimum_work, to_uintx(base16_hash("0000000000000000000000000000000000000000000000000000000000000000")));
+    BOOST_REQUIRE_EQUAL(configuration.milestone, genesis);
 }
 
 // setter methods