interfaces, refactor: Add more block information to block connected notifications

Add new interfaces::BlockInfo struct to be able to pass extra block
information (file and undo information) to indexes which they are
updated to use high level interfaces::Chain notifications.

This commit does not change behavior in any way.

8 files changed, 94 insertions, 21 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 02ec5c098e..87c7a056b1 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -171,6 +171,7 @@ BITCOIN_CORE_H = \
   interfaces/ipc.h \
   interfaces/node.h \
   interfaces/wallet.h \
+  kernel/chain.h \
   kernel/chainstatemanager_opts.h \
   kernel/checks.h \
   kernel/coinstats.h \
@@ -365,6 +366,7 @@ libbitcoin_node_a_SOURCES = \
   index/coinstatsindex.cpp \
   index/txindex.cpp \
   init.cpp \
+  kernel/chain.cpp \
   kernel/checks.cpp \
   kernel/coinstats.cpp \
   kernel/context.cpp \
diff --git a/src/interfaces/chain.h b/src/interfaces/chain.h
index ff994b8edc..6396d0d359 100644
--- a/src/interfaces/chain.h
+++ b/src/interfaces/chain.h
@@ -18,6 +18,7 @@
 
 class ArgsManager;
 class CBlock;
+class CBlockUndo;
 class CFeeRate;
 class CRPCCommand;
 class CScheduler;
@@ -67,6 +68,19 @@ public:
     mutable bool found = false;
 };
 
+//! Block data sent with blockConnected, blockDisconnected notifications.
+struct BlockInfo {
+    const uint256& hash;
+    const uint256* prev_hash = nullptr;
+    int height = -1;
+    int file_number = -1;
+    unsigned data_pos = 0;
+    const CBlock* data = nullptr;
+    const CBlockUndo* undo_data = nullptr;
+
+    BlockInfo(const uint256& hash LIFETIMEBOUND) : hash(hash) {}
+};
+
 //! Interface giving clients (wallet processes, maybe other analysis tools in
 //! the future) ability to access to the chain state, receive notifications,
 //! estimate fees, and submit transactions.
@@ -239,8 +253,8 @@ public:
         virtual ~Notifications() {}
         virtual void transactionAddedToMempool(const CTransactionRef& tx, uint64_t mempool_sequence) {}
         virtual void transactionRemovedFromMempool(const CTransactionRef& tx, MemPoolRemovalReason reason, uint64_t mempool_sequence) {}
-        virtual void blockConnected(const CBlock& block, int height) {}
-        virtual void blockDisconnected(const CBlock& block, int height) {}
+        virtual void blockConnected(const BlockInfo& block) {}
+        virtual void blockDisconnected(const BlockInfo& block) {}
         virtual void updatedBlockTip() {}
         virtual void chainStateFlushed(const CBlockLocator& locator) {}
     };
diff --git a/src/kernel/chain.cpp b/src/kernel/chain.cpp
new file mode 100644
index 0000000000..82e77125d7
--- /dev/null
+++ b/src/kernel/chain.cpp
@@ -0,0 +1,26 @@
+// Copyright (c) 2022 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <chain.h>
+#include <interfaces/chain.h>
+#include <sync.h>
+#include <uint256.h>
+
+class CBlock;
+
+namespace kernel {
+interfaces::BlockInfo MakeBlockInfo(const CBlockIndex* index, const CBlock* data)
+{
+    interfaces::BlockInfo info{index ? *index->phashBlock : uint256::ZERO};
+    if (index) {
+        info.prev_hash = index->pprev ? index->pprev->phashBlock : nullptr;
+        info.height = index->nHeight;
+        LOCK(::cs_main);
+        info.file_number = index->nFile;
+        info.data_pos = index->nDataPos;
+    }
+    info.data = data;
+    return info;
+}
+} // namespace kernel
diff --git a/src/kernel/chain.h b/src/kernel/chain.h
new file mode 100644
index 0000000000..f0750f8266
--- /dev/null
+++ b/src/kernel/chain.h
@@ -0,0 +1,19 @@
+// Copyright (c) 2022 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_KERNEL_CHAIN_H
+#define BITCOIN_KERNEL_CHAIN_H
+
+class CBlock;
+class CBlockIndex;
+namespace interfaces {
+struct BlockInfo;
+} // namespace interfaces
+
+namespace kernel {
+//! Return data from block index.
+interfaces::BlockInfo MakeBlockInfo(const CBlockIndex* block_index, const CBlock* data = nullptr);
+} // namespace kernel
+
+#endif // BITCOIN_KERNEL_CHAIN_H
diff --git a/src/node/interfaces.cpp b/src/node/interfaces.cpp
index 46e0efb9b6..2562d81e48 100644
--- a/src/node/interfaces.cpp
+++ b/src/node/interfaces.cpp
@@ -19,6 +19,7 @@
 #include <netaddress.h>
 #include <netbase.h>
 #include <node/blockstorage.h>
+#include <kernel/chain.h>
 #include <node/coin.h>
 #include <node/context.h>
 #include <node/transaction.h>
@@ -426,11 +427,11 @@ public:
     }
     void BlockConnected(const std::shared_ptr<const CBlock>& block, const CBlockIndex* index) override
     {
-        m_notifications->blockConnected(*block, index->nHeight);
+        m_notifications->blockConnected(kernel::MakeBlockInfo(index, block.get()));
     }
     void BlockDisconnected(const std::shared_ptr<const CBlock>& block, const CBlockIndex* index) override
     {
-        m_notifications->blockDisconnected(*block, index->nHeight);
+        m_notifications->blockDisconnected(kernel::MakeBlockInfo(index, block.get()));
     }
     void UpdatedBlockTip(const CBlockIndex* index, const CBlockIndex* fork_index, bool is_ibd) override
     {
diff --git a/src/wallet/test/fuzz/notifications.cpp b/src/wallet/test/fuzz/notifications.cpp
index 816bef6148..5c173773e4 100644
--- a/src/wallet/test/fuzz/notifications.cpp
+++ b/src/wallet/test/fuzz/notifications.cpp
@@ -137,8 +137,13 @@ FUZZ_TARGET_INIT(wallet_notifications, initialize_setup)
                     block.vtx.emplace_back(MakeTransactionRef(tx));
                 }
                 // Mine block
-                a.wallet->blockConnected(block, chain.size());
-                b.wallet->blockConnected(block, chain.size());
+                const uint256& hash = block.GetHash();
+                interfaces::BlockInfo info{hash};
+                info.prev_hash = &block.hashPrevBlock;
+                info.height = chain.size();
+                info.data = &block;
+                a.wallet->blockConnected(info);
+                b.wallet->blockConnected(info);
                 // Store the coins for the next block
                 Coins coins_new;
                 for (const auto& tx : block.vtx) {
@@ -154,8 +159,13 @@ FUZZ_TARGET_INIT(wallet_notifications, initialize_setup)
                 auto& [coins, block]{chain.back()};
                 if (block.vtx.empty()) return; // Can only disconnect if the block was submitted first
                 // Disconnect block
-                a.wallet->blockDisconnected(block, chain.size() - 1);
-                b.wallet->blockDisconnected(block, chain.size() - 1);
+                const uint256& hash = block.GetHash();
+                interfaces::BlockInfo info{hash};
+                info.prev_hash = &block.hashPrevBlock;
+                info.height = chain.size() - 1;
+                info.data = &block;
+                a.wallet->blockDisconnected(info);
+                b.wallet->blockDisconnected(info);
                 chain.pop_back();
             });
         auto& [coins, first_block]{chain.front()};
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 890e171913..c8d6ccd48b 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -1314,30 +1314,31 @@ void CWallet::transactionRemovedFromMempool(const CTransactionRef& tx, MemPoolRe
     }
 }
 
-void CWallet::blockConnected(const CBlock& block, int height)
+void CWallet::blockConnected(const interfaces::BlockInfo& block)
 {
-    const uint256& block_hash = block.GetHash();
+    assert(block.data);
     LOCK(cs_wallet);
 
-    m_last_block_processed_height = height;
-    m_last_block_processed = block_hash;
-    for (size_t index = 0; index < block.vtx.size(); index++) {
-        SyncTransaction(block.vtx[index], TxStateConfirmed{block_hash, height, static_cast<int>(index)});
-        transactionRemovedFromMempool(block.vtx[index], MemPoolRemovalReason::BLOCK, 0 /* mempool_sequence */);
+    m_last_block_processed_height = block.height;
+    m_last_block_processed = block.hash;
+    for (size_t index = 0; index < block.data->vtx.size(); index++) {
+        SyncTransaction(block.data->vtx[index], TxStateConfirmed{block.hash, block.height, static_cast<int>(index)});
+        transactionRemovedFromMempool(block.data->vtx[index], MemPoolRemovalReason::BLOCK, 0 /* mempool_sequence */);
     }
 }
 
-void CWallet::blockDisconnected(const CBlock& block, int height)
+void CWallet::blockDisconnected(const interfaces::BlockInfo& block)
 {
+    assert(block.data);
     LOCK(cs_wallet);
 
     // At block disconnection, this will change an abandoned transaction to
     // be unconfirmed, whether or not the transaction is added back to the mempool.
     // User may have to call abandontransaction again. It may be addressed in the
     // future with a stickier abandoned state or even removing abandontransaction call.
-    m_last_block_processed_height = height - 1;
-    m_last_block_processed = block.hashPrevBlock;
-    for (const CTransactionRef& ptx : block.vtx) {
+    m_last_block_processed_height = block.height - 1;
+    m_last_block_processed = *Assert(block.prev_hash);
+    for (const CTransactionRef& ptx : Assert(block.data)->vtx) {
         SyncTransaction(ptx, TxStateInactive{});
     }
 }
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index e2c3d76438..15f5917040 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -508,8 +508,8 @@ public:
     CWalletTx* AddToWallet(CTransactionRef tx, const TxState& state, const UpdateWalletTxFn& update_wtx=nullptr, bool fFlushOnClose=true, bool rescanning_old_block = false);
     bool LoadToWallet(const uint256& hash, const UpdateWalletTxFn& fill_wtx) EXCLUSIVE_LOCKS_REQUIRED(cs_wallet);
     void transactionAddedToMempool(const CTransactionRef& tx, uint64_t mempool_sequence) override;
-    void blockConnected(const CBlock& block, int height) override;
-    void blockDisconnected(const CBlock& block, int height) override;
+    void blockConnected(const interfaces::BlockInfo& block) override;
+    void blockDisconnected(const interfaces::BlockInfo& block) override;
     void updatedBlockTip() override;
     int64_t RescanFromTime(int64_t startTime, const WalletRescanReserver& reserver, bool update);