Merge #21391: [Bundle 5/n] Prune g_chainman usage in RPC modules

586190f rpc/rest: Take and reuse local Chain/ChainState obj (Carl Dong)
bc3bd36 rpc: style: Improve BuriedForkDescPushBack signature (Carl Dong)
f999139 rpc: Remove unnecessary casting of block height (Carl Dong)
6a3d192 rpc: Tidy up local references (see commit message) (Carl Dong)
038854f rest/rpc: Remove now-unused old Ensure functions (Carl Dong)
6fb65b4 scripted-diff: rest/rpc: Use renamed EnsureAny*() (Carl Dong)
1570c7e rpc: Add renamed EnsureAny*() functions (Carl Dong)
306b1cd rpc: Add alt Ensure* functions acepting NodeContext (Carl Dong)
d7824ac rest: Use existing NodeContext (Carl Dong)
3f08934 rest: Pass in NodeContext to rest_block (Carl Dong)
7be0671 rpc/rawtx: Use existing NodeContext (Carl Dong)
60dc05a rpc/mining: Use existing NodeContext (Carl Dong)
d485e81 rpc/blockchain: Use existing NodeContext (Carl Dong)
d0abf0b rpc/*,rest: Add review-only assertion to EnsureChainman (Carl Dong)
cced0f4 miner: Pass in previous CBlockIndex to RegenerateCommitments (Carl Dong)

Pull request description:

  Overall PR: #20158 (tree-wide: De-globalize ChainstateManager)

  Based on:
  - [x] #21270 | [Bundle 4/n] Prune g_chainman usage in validation-adjacent modules
  - [x] #21525 | [Bundle 4.5/n] Followup fixups to bundle 4

  Note to reviewers:
  1. This bundle may _apparently_ introduce usage of `g_chainman` or `::Chain(state|)Active()` globals, but these are resolved later on in the overall PR. [Commits of overall PR](https://github.com/bitcoin/bitcoin/pull/20158/commits)
  2. There may be seemingly obvious local references to `ChainstateManager` or other validation objects which are not being used in callers of the current function in question, this is done intentionally to **_keep each commit centered around one function/method_** to ease review and to make the overall change systematic. We don't assume anything about our callers. Rest assured that once we are considering that particular caller in later commits, we will use the obvious local references. [Commits of overall PR](https://github.com/bitcoin/bitcoin/pull/20158/commits)
  3. When changing a function/method that has many callers (e.g. `LookupBlockIndex` with 55 callers), it is sometimes easier (and less error-prone) to use a scripted-diff. When doing so, there will be 3 commits in sequence so that every commit compiles like so:
  	1. Add `new_function`, make `old_function` a wrapper of `new_function`, divert all calls to `old_function` to `new_function` **in the local module only**
  	2. Scripted-diff to divert all calls to `old_function` to `new_function` **in the rest of the codebase**
  	3. Remove `old_function`

ACKs for top commit:
  ryanofsky:
    Code review ACK 586190f. Since last review, no changes to existing commits, just some simple new commits added: three new commits renaming std::any Ensure functions (scripted diff commit and manual pre/post commits), and one new commit factoring out a repeated `ActiveChain()` call made in a loop. Thanks for the updates!
  jnewbery:
    utACK 586190f
  MarcoFalke:
    review ACK 586190f 🍯

Tree-SHA512: 64b677fb50141805b55c3f1afe68fcd298f9a071a359bdcd63256d52e334f83e462f31fb3ebee9b630da8f1d912a03a128cfc38179e7aaec29a055744a98478c

Author: MarcoFalke

src/miner.cpp

@@ -39,13 +39,14 @@ int64_t UpdateTime(CBlockHeader* pblock, const Consensus::Params& consensusParam
     return nNewTime - nOldTime;
 }
 
-void RegenerateCommitments(CBlock& block, BlockManager& blockman)
+void RegenerateCommitments(CBlock& block, CBlockIndex* prev_block)
 {
     CMutableTransaction tx{*block.vtx.at(0)};
     tx.vout.erase(tx.vout.begin() + GetWitnessCommitmentIndex(block));
     block.vtx.at(0) = MakeTransactionRef(tx);
 
-    GenerateCoinbaseCommitment(block, WITH_LOCK(::cs_main, assert(std::addressof(g_chainman.m_blockman) == std::addressof(blockman)); return blockman.LookupBlockIndex(block.hashPrevBlock)), Params().GetConsensus());
+    WITH_LOCK(::cs_main, assert(g_chainman.m_blockman.LookupBlockIndex(block.hashPrevBlock) == prev_block));
+    GenerateCoinbaseCommitment(block, prev_block, Params().GetConsensus());
 
     block.hashMerkleRoot = BlockMerkleRoot(block);
 }

src/miner.h

@@ -202,8 +202,7 @@ class BlockAssembler
 void IncrementExtraNonce(CBlock* pblock, const CBlockIndex* pindexPrev, unsigned int& nExtraNonce);
 int64_t UpdateTime(CBlockHeader* pblock, const Consensus::Params& consensusParams, const CBlockIndex* pindexPrev);
 
-// TODO just accept a CBlockIndex*
 /** Update an old GenerateCoinbaseCommitment from CreateNewBlock after the block txs have changed */
-void RegenerateCommitments(CBlock& block, BlockManager& blockman);
+void RegenerateCommitments(CBlock& block, CBlockIndex* prev_block);
 
 #endif // BITCOIN_MINER_H

src/rest.cpp

@@ -181,14 +181,16 @@ static bool rest_headers(const std::any& context,
     std::vector<const CBlockIndex *> headers;
     headers.reserve(count);
     {
+        ChainstateManager& chainman = EnsureAnyChainman(context);
         LOCK(cs_main);
-        tip = ::ChainActive().Tip();
-        const CBlockIndex* pindex = g_chainman.m_blockman.LookupBlockIndex(hash);
-        while (pindex != nullptr && ::ChainActive().Contains(pindex)) {
+        CChain& active_chain = chainman.ActiveChain();
+        tip = active_chain.Tip();
+        const CBlockIndex* pindex = chainman.m_blockman.LookupBlockIndex(hash);
+        while (pindex != nullptr && active_chain.Contains(pindex)) {
             headers.push_back(pindex);
             if (headers.size() == (unsigned long)count)
                 break;
-            pindex = ::ChainActive().Next(pindex);
+            pindex = active_chain.Next(pindex);
         }
     }
 
@@ -232,7 +234,8 @@ static bool rest_headers(const std::any& context,
     }
 }
 
-static bool rest_block(HTTPRequest* req,
+static bool rest_block(const std::any& context,
+                       HTTPRequest* req,
                        const std::string& strURIPart,
                        bool showTxDetails)
 {
@@ -249,9 +252,10 @@ static bool rest_block(HTTPRequest* req,
     CBlockIndex* pblockindex = nullptr;
     CBlockIndex* tip = nullptr;
     {
+        ChainstateManager& chainman = EnsureAnyChainman(context);
         LOCK(cs_main);
-        tip = ::ChainActive().Tip();
-        pblockindex = g_chainman.m_blockman.LookupBlockIndex(hash);
+        tip = chainman.ActiveChain().Tip();
+        pblockindex = chainman.m_blockman.LookupBlockIndex(hash);
         if (!pblockindex) {
             return RESTERR(req, HTTP_NOT_FOUND, hashStr + " not found");
         }
@@ -298,12 +302,12 @@ static bool rest_block(HTTPRequest* req,
 
 static bool rest_block_extended(const std::any& context, HTTPRequest* req, const std::string& strURIPart)
 {
-    return rest_block(req, strURIPart, true);
+    return rest_block(context, req, strURIPart, true);
 }
 
 static bool rest_block_notxdetails(const std::any& context, HTTPRequest* req, const std::string& strURIPart)
 {
-    return rest_block(req, strURIPart, false);
+    return rest_block(context, req, strURIPart, false);
 }
 
 // A bit of a hack - dependency on a function defined in rpc/blockchain.cpp
@@ -537,6 +541,7 @@ static bool rest_getutxos(const std::any& context, HTTPRequest* req, const std::
     std::string bitmapStringRepresentation;
     std::vector<bool> hits;
     bitmap.resize((vOutPoints.size() + 7) / 8);
+    ChainstateManager& chainman = EnsureAnyChainman(context);
     {
         auto process_utxos = [&vOutPoints, &outs, &hits](const CCoinsView& view, const CTxMemPool& mempool) {
             for (const COutPoint& vOutPoint : vOutPoints) {
@@ -552,12 +557,12 @@ static bool rest_getutxos(const std::any& context, HTTPRequest* req, const std::
             if (!mempool) return false;
             // use db+mempool as cache backend in case user likes to query mempool
             LOCK2(cs_main, mempool->cs);
-            CCoinsViewCache& viewChain = ::ChainstateActive().CoinsTip();
+            CCoinsViewCache& viewChain = chainman.ActiveChainstate().CoinsTip();
             CCoinsViewMemPool viewMempool(&viewChain, *mempool);
             process_utxos(viewMempool, *mempool);
         } else {
             LOCK(cs_main);  // no need to lock mempool!
-            process_utxos(::ChainstateActive().CoinsTip(), CTxMemPool());
+            process_utxos(chainman.ActiveChainstate().CoinsTip(), CTxMemPool());
         }
 
         for (size_t i = 0; i < hits.size(); ++i) {
@@ -572,7 +577,7 @@ static bool rest_getutxos(const std::any& context, HTTPRequest* req, const std::
         // serialize data
         // use exact same output as mentioned in Bip64
         CDataStream ssGetUTXOResponse(SER_NETWORK, PROTOCOL_VERSION);
-        ssGetUTXOResponse << ::ChainActive().Height() << ::ChainActive().Tip()->GetBlockHash() << bitmap << outs;
+        ssGetUTXOResponse << chainman.ActiveChain().Height() << chainman.ActiveChain().Tip()->GetBlockHash() << bitmap << outs;
         std::string ssGetUTXOResponseString = ssGetUTXOResponse.str();
 
         req->WriteHeader("Content-Type", "application/octet-stream");
@@ -582,7 +587,7 @@ static bool rest_getutxos(const std::any& context, HTTPRequest* req, const std::
 
     case RetFormat::HEX: {
         CDataStream ssGetUTXOResponse(SER_NETWORK, PROTOCOL_VERSION);
-        ssGetUTXOResponse << ::ChainActive().Height() << ::ChainActive().Tip()->GetBlockHash() << bitmap << outs;
+        ssGetUTXOResponse << chainman.ActiveChain().Height() << chainman.ActiveChain().Tip()->GetBlockHash() << bitmap << outs;
         std::string strHex = HexStr(ssGetUTXOResponse) + "\n";
 
         req->WriteHeader("Content-Type", "text/plain");
@@ -595,8 +600,8 @@ static bool rest_getutxos(const std::any& context, HTTPRequest* req, const std::
 
         // pack in some essentials
         // use more or less the same output as mentioned in Bip64
-        objGetUTXOResponse.pushKV("chainHeight", ::ChainActive().Height());
-        objGetUTXOResponse.pushKV("chaintipHash", ::ChainActive().Tip()->GetBlockHash().GetHex());
+        objGetUTXOResponse.pushKV("chainHeight", chainman.ActiveChain().Height());
+        objGetUTXOResponse.pushKV("chaintipHash", chainman.ActiveChain().Tip()->GetBlockHash().GetHex());
         objGetUTXOResponse.pushKV("bitmap", bitmapStringRepresentation);
 
         UniValue utxos(UniValue::VARR);
@@ -639,11 +644,13 @@ static bool rest_blockhash_by_height(const std::any& context, HTTPRequest* req,
 
     CBlockIndex* pblockindex = nullptr;
     {
+        ChainstateManager& chainman = EnsureAnyChainman(context);
         LOCK(cs_main);
-        if (blockheight > ::ChainActive().Height()) {
+        const CChain& active_chain = chainman.ActiveChain();
+        if (blockheight > active_chain.Height()) {
             return RESTERR(req, HTTP_NOT_FOUND, "Block height out of range");
         }
-        pblockindex = ::ChainActive()[blockheight];
+        pblockindex = active_chain[blockheight];
     }
     switch (rf) {
     case RetFormat::BINARY: {