Merge bitcoin/bitcoin#25016: refactor: GetFirstStoredBlock() and getblockchaininfo follow-ups

e2b954e rpc: use GetBlockTime() for getblockchaininfo#time (Jon Atack)
86ce844 blockstorage, refactor: pass GetFirstStoredBlock() start_block by reference (Jon Atack)
ed12c0a blockstorage, refactor: make GetFirstStoredBlock() a member of BlockManager (Jon Atack)

Pull request description:

  Picks up the remaining review feedback in #21726 and #24956.

  - make the global function `GetFirstStoredBlock()` a member of the `BlockManager` class
  - pass the `start_block` param of `GetFirstStoredBlock()` by reference instead of a pointer
  - use `GetBlockTime()` for RPC getblockchaininfo#time

ACKs for top commit:
  MarcoFalke:
    ACK e2b954e

Tree-SHA512: 546e3c2e18245996b5b286829a605ae919eff3510963ec71b7c9ede521b1f501697e5b2f9d35d7a0606a74cbc8907201c58acf1e2cf7daaa86eefe2e3a8e296b

Author: fanquake

src/index/base.cpp

@@ -75,7 +75,7 @@ bool BaseIndex::Init()
         if (!m_best_block_index) {
             // index is not built yet
             // make sure we have all block data back to the genesis
-            prune_violation = node::GetFirstStoredBlock(active_chain.Tip()) != active_chain.Genesis();
+            prune_violation = m_chainstate->m_blockman.GetFirstStoredBlock(*active_chain.Tip()) != active_chain.Genesis();
         }
         // in case the index has a best block set and is not fully synced
         // check if we have the required blocks to continue building the index

src/node/blockstorage.cpp

@@ -390,10 +390,10 @@ bool BlockManager::IsBlockPruned(const CBlockIndex* pblockindex)
     return (m_have_pruned && !(pblockindex->nStatus & BLOCK_HAVE_DATA) && pblockindex->nTx > 0);
 }
 
-const CBlockIndex* GetFirstStoredBlock(const CBlockIndex* start_block) {
+const CBlockIndex* BlockManager::GetFirstStoredBlock(const CBlockIndex& start_block)
+{
     AssertLockHeld(::cs_main);
-    assert(start_block);
-    const CBlockIndex* last_block = start_block;
+    const CBlockIndex* last_block = &start_block;
     while (last_block->pprev && (last_block->pprev->nStatus & BLOCK_HAVE_DATA)) {
         last_block = last_block->pprev;
     }

src/node/blockstorage.h

@@ -178,6 +178,9 @@ class BlockManager
     //! Returns last CBlockIndex* that is a checkpoint
     const CBlockIndex* GetLastCheckpoint(const CCheckpointData& data) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
+    //! Find the first block that is not pruned
+    const CBlockIndex* GetFirstStoredBlock(const CBlockIndex& start_block) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
+
     /** True if any block files have ever been pruned. */
     bool m_have_pruned = false;
 
@@ -188,9 +191,6 @@ class BlockManager
     void UpdatePruneLock(const std::string& name, const PruneLockInfo& lock_info) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 };
 
-//! Find the first block that is not pruned
-const CBlockIndex* GetFirstStoredBlock(const CBlockIndex* start_block) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
-
 void CleanupBlockRevFiles();
 
 /** Open a block file (blk?????.dat) */

src/rpc/blockchain.cpp

@@ -760,8 +760,9 @@ static RPCHelpMan pruneblockchain()
     CChain& active_chain = active_chainstate.m_chain;
 
     int heightParam = request.params[0].get_int();
-    if (heightParam < 0)
+    if (heightParam < 0) {
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Negative block height.");
+    }
 
     // Height value more than a billion is too high to be a block height, and
     // too low to be a block time (corresponds to timestamp from Sep 2001).
@@ -786,8 +787,8 @@ static RPCHelpMan pruneblockchain()
     }
 
     PruneBlockFilesManual(active_chainstate, height);
-    const CBlockIndex* block = CHECK_NONFATAL(active_chain.Tip());
-    const CBlockIndex* last_block = node::GetFirstStoredBlock(block);
+    const CBlockIndex& block{*CHECK_NONFATAL(active_chain.Tip())};
+    const CBlockIndex* last_block{active_chainstate.m_blockman.GetFirstStoredBlock(block)};
 
     return static_cast<uint64_t>(last_block->nHeight);
 },
@@ -1207,15 +1208,15 @@ RPCHelpMan getblockchaininfo()
     obj.pushKV("headers", chainman.m_best_header ? chainman.m_best_header->nHeight : -1);
     obj.pushKV("bestblockhash", tip.GetBlockHash().GetHex());
     obj.pushKV("difficulty", GetDifficulty(&tip));
-    obj.pushKV("time", int64_t{tip.nTime});
+    obj.pushKV("time", tip.GetBlockTime());
     obj.pushKV("mediantime", tip.GetMedianTimePast());
     obj.pushKV("verificationprogress", GuessVerificationProgress(Params().TxData(), &tip));
     obj.pushKV("initialblockdownload", active_chainstate.IsInitialBlockDownload());
     obj.pushKV("chainwork", tip.nChainWork.GetHex());
     obj.pushKV("size_on_disk", chainman.m_blockman.CalculateCurrentUsage());
     obj.pushKV("pruned", node::fPruneMode);
     if (node::fPruneMode) {
-        obj.pushKV("pruneheight", node::GetFirstStoredBlock(&tip)->nHeight);
+        obj.pushKV("pruneheight", chainman.m_blockman.GetFirstStoredBlock(tip)->nHeight);
 
         // if 0, execution bypasses the whole if block.
         bool automatic_pruning{args.GetIntArg("-prune", 0) != 1};