Merge #20584: Declare de facto const reference variables/member functions as const

31b136e Don't declare de facto const reference variables as non-const (practicalswift)
1c65c07 Don't declare de facto const member functions as non-const (practicalswift)

Pull request description:

  _Meta: This is the second and final part of the `const` refactoring series (part one: #20581). **I promise: no more refactoring PRs from me in a while! :)** I'll now go back to focusing on fuzzing/hardening!_

  Changes in this PR:
  * Don't declare de facto const member functions as non-const
  * Don't declare de facto const reference variables as non-const

  Awards for finding candidates for the above changes go to:
  * `clang-tidy`'s [`readability-make-member-function-const`](https://clang.llvm.org/extra/clang-tidy/checks/readability-make-member-function-const.html)  check ([list of `clang-tidy` checks](https://clang.llvm.org/extra/clang-tidy/checks/list.html))
  * `cppcheck`'s `constVariable` check ([list of `cppcheck` checks](https://sourceforge.net/p/cppcheck/wiki/ListOfChecks/))

  See #18920 for instructions on how to analyse Bitcoin Core using Clang Static Analysis, `clang-tidy` and `cppcheck`.

ACKs for top commit:
  ajtowns:
    ACK 31b136e
  jonatack:
    ACK 31b136e
  theStack:
    ACK 31b136e ❄️

Tree-SHA512: f58f8f00744219426874379e9f3e9331132b9b48e954d24f3a85cbb858fdcc98009ed42ef7e7b4619ae8af9fc240a6d8bfc1c438db2e97b0ecd722a80dcfeffe

Author: MarcoFalke

src/addrman.cpp

@@ -617,7 +617,7 @@ CAddrInfo CAddrMan::SelectTriedCollision_()
         return CAddrInfo();
     }
 
-    CAddrInfo& newInfo = mapInfo[id_new];
+    const CAddrInfo& newInfo = mapInfo[id_new];
 
     // which tried bucket to move the entry to
     int tried_bucket = newInfo.GetTriedBucket(nKey, m_asmap);

src/logging.cpp

@@ -174,7 +174,7 @@ bool GetLogCategory(BCLog::LogFlags& flag, const std::string& str)
     return false;
 }
 
-std::vector<LogCategory> BCLog::Logger::LogCategoriesList()
+std::vector<LogCategory> BCLog::Logger::LogCategoriesList() const
 {
     std::vector<LogCategory> ret;
     for (const CLogCategoryDesc& category_desc : LogCategories) {

src/logging.h

@@ -135,9 +135,9 @@ namespace BCLog {
 
         bool WillLogCategory(LogFlags category) const;
         /** Returns a vector of the log categories */
-        std::vector<LogCategory> LogCategoriesList();
+        std::vector<LogCategory> LogCategoriesList() const;
         /** Returns a string with the log categories */
-        std::string LogCategoriesString()
+        std::string LogCategoriesString() const
         {
             return Join(LogCategoriesList(), ", ", [&](const LogCategory& i) { return i.category; });
         };

src/miner.cpp

@@ -213,7 +213,7 @@ bool BlockAssembler::TestPackage(uint64_t packageSize, int64_t packageSigOpsCost
 // - transaction finality (locktime)
 // - premature witness (in case segwit transactions are added to mempool before
 //   segwit activation)
-bool BlockAssembler::TestPackageTransactions(const CTxMemPool::setEntries& package)
+bool BlockAssembler::TestPackageTransactions(const CTxMemPool::setEntries& package) const
 {
     for (CTxMemPool::txiter it : package) {
         if (!IsFinalTx(it->GetTx(), nHeight, nLockTimeCutoff))

src/miner.h

@@ -185,7 +185,7 @@ class BlockAssembler
       * locktime, premature-witness, serialized size (if necessary)
       * These checks should always succeed, and they're here
       * only as an extra check in case of suboptimal node configuration */
-    bool TestPackageTransactions(const CTxMemPool::setEntries& package);
+    bool TestPackageTransactions(const CTxMemPool::setEntries& package) const;
     /** Return true if given transaction from mapTx has already been evaluated,
       * or if the transaction's cached data in mapTx is incorrect. */
     bool SkipMapTxEntry(CTxMemPool::txiter it, indexed_modified_transaction_set& mapModifiedTx, CTxMemPool::setEntries& failedTx) EXCLUSIVE_LOCKS_REQUIRED(m_mempool.cs);

src/net.cpp

@@ -1206,7 +1206,7 @@ void CConnman::NotifyNumConnectionsChanged()
     }
 }
 
-void CConnman::InactivityCheck(CNode *pnode)
+void CConnman::InactivityCheck(CNode *pnode) const
 {
     int64_t nTime = GetSystemTimeInSeconds();
     if (nTime - pnode->nTimeConnected > m_peer_connect_timeout)

src/net.h

@@ -420,7 +420,7 @@ class CConnman
     void AcceptConnection(const ListenSocket& hListenSocket);
     void DisconnectNodes();
     void NotifyNumConnectionsChanged();
-    void InactivityCheck(CNode *pnode);
+    void InactivityCheck(CNode *pnode) const;
     bool GenerateSelectSet(std::set<SOCKET> &recv_set, std::set<SOCKET> &send_set, std::set<SOCKET> &error_set);
     void SocketEvents(std::set<SOCKET> &recv_set, std::set<SOCKET> &send_set, std::set<SOCKET> &error_set);
     void SocketHandler();

src/rpc/blockchain.cpp

@@ -66,7 +66,7 @@ NodeContext& EnsureNodeContext(const util::Ref& context)
 
 CTxMemPool& EnsureMemPool(const util::Ref& context)
 {
-    NodeContext& node = EnsureNodeContext(context);
+    const NodeContext& node = EnsureNodeContext(context);
     if (!node.mempool) {
         throw JSONRPCError(RPC_CLIENT_MEMPOOL_DISABLED, "Mempool disabled or instance not found");
     }
@@ -75,7 +75,7 @@ CTxMemPool& EnsureMemPool(const util::Ref& context)
 
 ChainstateManager& EnsureChainman(const util::Ref& context)
 {
-    NodeContext& node = EnsureNodeContext(context);
+    const NodeContext& node = EnsureNodeContext(context);
     if (!node.chainman) {
         throw JSONRPCError(RPC_INTERNAL_ERROR, "Node chainman not found");
     }

src/script/interpreter.cpp

@@ -305,8 +305,8 @@ class ConditionStack {
     uint32_t m_first_false_pos = NO_FALSE;
 
 public:
-    bool empty() { return m_stack_size == 0; }
-    bool all_true() { return m_first_false_pos == NO_FALSE; }
+    bool empty() const { return m_stack_size == 0; }
+    bool all_true() const { return m_first_false_pos == NO_FALSE; }
     void push_back(bool f)
     {
         if (m_first_false_pos == NO_FALSE && !f) {

src/script/sign.cpp

@@ -388,7 +388,7 @@ bool SignSignature(const SigningProvider &provider, const CScript& fromPubKey, C
 bool SignSignature(const SigningProvider &provider, const CTransaction& txFrom, CMutableTransaction& txTo, unsigned int nIn, int nHashType)
 {
     assert(nIn < txTo.vin.size());
-    CTxIn& txin = txTo.vin[nIn];
+    const CTxIn& txin = txTo.vin[nIn];
     assert(txin.prevout.n < txFrom.vout.size());
     const CTxOut& txout = txFrom.vout[txin.prevout.n];