Merge pull request #433 from evoskuil/master

Move hash parsing optimizations to system, delete block memory if fails.

include/bitcoin/network/messages/block.hpp

@@ -39,10 +39,6 @@ struct BCT_API block
     static const uint32_t version_minimum;
     static const uint32_t version_maximum;
 
-    /// Populate header and tx hashes onto the block.
-    static void set_hashes(const system::chain::block& block,
-        const system::data_chunk& data) NOEXCEPT;
-
     static cptr deserialize(arena& arena, uint32_t version,
         const system::data_chunk& data, bool witness=true) NOEXCEPT;
     static cptr deserialize(uint32_t version, const system::data_chunk& data,

include/bitcoin/network/messages/transaction.hpp

@@ -38,9 +38,6 @@ struct BCT_API transaction
     static const uint32_t version_minimum;
     static const uint32_t version_maximum;
 
-    static system::hash_digest desegregated_hash(size_t witnessed,
-        size_t unwitnessed, const uint8_t* data) NOEXCEPT;
-
     static cptr deserialize(uint32_t version, const system::data_chunk& data,
         bool witness=true) NOEXCEPT;
     static transaction deserialize(uint32_t version, system::reader& source,

src/messages/block.cpp

@@ -44,48 +44,9 @@ const identifier block::id = identifier::block;
 const uint32_t block::version_minimum = level::minimum_protocol;
 const uint32_t block::version_maximum = level::maximum_protocol;
 
-// static
-void block::set_hashes(const chain::block& block, const data_chunk& data) NOEXCEPT
-{
-    constexpr auto header_size = chain::header::serialized_size();
-
-    // Cache header hash.
-    block.header().set_hash(bitcoin_hash(header_size, data.data()));
-
-    // Skip transaction count, guarded by preceding successful block construct.
-    auto start = std::next(data.data(), header_size);
-    std::advance(start, size_variable(*start));
-
-    // Cache transaction hashes.
-    auto coinbase = true;
-    for (const auto& tx: *block.transactions_ptr())
-    {
-        const auto witness_size = tx->serialized_size(true);
-
-        // If !witness then wire txs cannot have been segregated.
-        if (tx->is_segregated())
-        {
-            const auto nominal_size = tx->serialized_size(false);
-
-            tx->set_nominal_hash(transaction::desegregated_hash(
-                witness_size, nominal_size, start));
-
-            if (!coinbase)
-                tx->set_witness_hash(bitcoin_hash(witness_size, start));
-        }
-        else
-        {
-            tx->set_nominal_hash(bitcoin_hash(witness_size, start));
-        }
-
-        coinbase = false;
-        std::advance(start, witness_size);
-    }
-}
-
 // static
 typename block::cptr block::deserialize(uint32_t version,
-    const system::data_chunk& data, bool witness) NOEXCEPT
+    const data_chunk& data, bool witness) NOEXCEPT
 {
     static default_memory memory{};
     return deserialize(*memory.get_arena(), version, data, witness);
@@ -105,10 +66,20 @@ typename block::cptr block::deserialize(arena& arena, uint32_t version,
     byte_reader reader{ source, &arena };
     auto& allocator = reader.get_allocator();
     const auto block = allocator.new_object<chain::block>(reader, witness);
-    if (is_null(block) || !reader)
+
+    // Destruct block if created but failed to deserialize.
+    if (!reader && !is_null(block))
+        byte_allocator::deleter<chain::block>(&arena);
+
+    // Release memory if block construction or deserialization failed.
+    if (!reader || is_null(block))
+    {
+        arena.release(memory);
         return nullptr;
+    }
 
-    set_hashes(*block, data);
+    // Cache hashes as extracted from serialized block.
+    block->set_hashes(data);
 
     // Set size of block allocation owned by memory (zero if non-detachable).
     block->set_allocation(arena.detach());
@@ -121,7 +92,6 @@ typename block::cptr block::deserialize(arena& arena, uint32_t version,
             byte_allocator::deleter<chain::block>(&arena);
 
             // Deallocate detached memory (nop if not detachable).
-            // Follows destructor just in case a destructor traverses memory.
             arena.release(memory);
         }));
 }

src/messages/transaction.cpp

@@ -35,27 +35,6 @@ const identifier transaction::id = identifier::transaction;
 const uint32_t transaction::version_minimum = level::minimum_protocol;
 const uint32_t transaction::version_maximum = level::maximum_protocol;
 
-// Optimized non-witness hash derivation using witness-serialized tx.
-hash_digest transaction::desegregated_hash(size_t witnessed,
-    size_t unwitnessed, const uint8_t* data) NOEXCEPT
-{
-    BC_ASSERT_MSG(!is_null(data), "nullptr");
-
-    using namespace system;
-    constexpr auto preamble = sizeof(uint32_t) + two * sizeof(uint8_t);
-    const auto puts = floored_subtract(unwitnessed, two * sizeof(uint32_t));
-    const auto locktime = floored_subtract(witnessed, sizeof(uint32_t));
-
-    hash_digest digest{};
-    stream::out::fast stream{ digest };
-    hash::sha256x2::fast sink{ stream };
-    sink.write_bytes(data, sizeof(uint32_t));
-    sink.write_bytes(std::next(data, preamble), puts);
-    sink.write_bytes(std::next(data, locktime), sizeof(uint32_t));
-    sink.flush();
-    return digest;
-}
-
 // static
 typename transaction::cptr transaction::deserialize(uint32_t version,
     const data_chunk& data, bool witness) NOEXCEPT
@@ -75,8 +54,8 @@ typename transaction::cptr transaction::deserialize(uint32_t version,
         const auto true_size = tx.serialized_size(true);
         const auto false_size = tx.serialized_size(false);
         tx.set_witness_hash(bitcoin_hash(true_size, data.data()));
-        tx.set_nominal_hash(desegregated_hash(true_size, false_size,
-            data.data()));
+        tx.set_nominal_hash(chain::transaction::desegregated_hash(
+            true_size, false_size, data.data()));
     }
     else
     {