Merge #13017: Add wallets management functions

3c058fd wallet: Add HasWallets (João Barbosa)
373aee2 wallet: Add AddWallet, RemoveWallet, GetWallet and GetWallets (João Barbosa)
6efd964 refactor: Drop CWalletRef typedef (João Barbosa)

Pull request description:

  This is a small step towards dynamic wallet load/unload. The wallets *registry* `vpwallets` is used in several places. With these new functions all `vpwallets` usage are removed and `vpwallets` is now a static variable (no external linkage).

  The typedef `CWalletRef` is also removed as it is narrowly used.

Tree-SHA512: 2ea19da2e17b521ad678bfe10f3257e497ccaf7ab9fd0b6647f9d829f1d6131cfa68db8e8492421711c6da399859432b963a568bdd4ca40a77dd95b597839423

9 files changed, 80 insertions, 41 deletions

diff --git a/src/interfaces/node.cpp b/src/interfaces/node.cpp
index ddd5496a80..e55cba3c65 100644
--- a/src/interfaces/node.cpp
+++ b/src/interfaces/node.cpp
@@ -236,7 +236,7 @@ class NodeImpl : public Node
     {
 #ifdef ENABLE_WALLET
         std::vector<std::unique_ptr<Wallet>> wallets;
-        for (CWalletRef wallet : ::vpwallets) {
+        for (CWallet* wallet : GetWallets()) {
             wallets.emplace_back(MakeWallet(*wallet));
         }
         return wallets;
diff --git a/src/qt/test/wallettests.cpp b/src/qt/test/wallettests.cpp
index dcc834c352..56d2d38194 100644
--- a/src/qt/test/wallettests.cpp
+++ b/src/qt/test/wallettests.cpp
@@ -180,9 +180,9 @@ void TestGUI()
     TransactionView transactionView(platformStyle.get());
     auto node = interfaces::MakeNode();
     OptionsModel optionsModel(*node);
-    vpwallets.insert(vpwallets.begin(), &wallet);
-    WalletModel walletModel(std::move(node->getWallets()[0]), *node, platformStyle.get(), &optionsModel);
-    vpwallets.erase(vpwallets.begin());
+    AddWallet(&wallet);
+    WalletModel walletModel(std::move(node->getWallets().back()), *node, platformStyle.get(), &optionsModel);
+    RemoveWallet(&wallet);
     sendCoinsDialog.setModel(&walletModel);
     transactionView.setModel(&walletModel);
 
diff --git a/src/rpc/misc.cpp b/src/rpc/misc.cpp
index 49e865a64a..6754407dbd 100644
--- a/src/rpc/misc.cpp
+++ b/src/rpc/misc.cpp
@@ -69,7 +69,7 @@ UniValue validateaddress(const JSONRPCRequest& request)
     {
 
 #ifdef ENABLE_WALLET
-        if (!::vpwallets.empty() && IsDeprecatedRPCEnabled("validateaddress")) {
+        if (HasWallets() && IsDeprecatedRPCEnabled("validateaddress")) {
             ret.pushKVs(getaddressinfo(request));
         }
 #endif
diff --git a/src/wallet/init.cpp b/src/wallet/init.cpp
index 2fd9aa1a6f..8b834e4626 100644
--- a/src/wallet/init.cpp
+++ b/src/wallet/init.cpp
@@ -315,7 +315,7 @@ bool WalletInit::Open() const
         if (!pwallet) {
             return false;
         }
-        vpwallets.push_back(pwallet);
+        AddWallet(pwallet);
     }
 
     return true;
@@ -323,29 +323,29 @@ bool WalletInit::Open() const
 
 void WalletInit::Start(CScheduler& scheduler) const
 {
-    for (CWalletRef pwallet : vpwallets) {
+    for (CWallet* pwallet : GetWallets()) {
         pwallet->postInitProcess(scheduler);
     }
 }
 
 void WalletInit::Flush() const
 {
-    for (CWalletRef pwallet : vpwallets) {
+    for (CWallet* pwallet : GetWallets()) {
         pwallet->Flush(false);
     }
 }
 
 void WalletInit::Stop() const
 {
-    for (CWalletRef pwallet : vpwallets) {
+    for (CWallet* pwallet : GetWallets()) {
         pwallet->Flush(true);
     }
 }
 
 void WalletInit::Close() const
 {
-    for (CWalletRef pwallet : vpwallets) {
+    for (CWallet* pwallet : GetWallets()) {
+        RemoveWallet(pwallet);
         delete pwallet;
     }
-    vpwallets.clear();
 }
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 56bdc0695c..9b5fb0b062 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -46,14 +46,13 @@ CWallet *GetWalletForJSONRPCRequest(const JSONRPCRequest& request)
     if (request.URI.substr(0, WALLET_ENDPOINT_BASE.size()) == WALLET_ENDPOINT_BASE) {
         // wallet endpoint was used
         std::string requestedWallet = urlDecode(request.URI.substr(WALLET_ENDPOINT_BASE.size()));
-        for (CWalletRef pwallet : ::vpwallets) {
-            if (pwallet->GetName() == requestedWallet) {
-                return pwallet;
-            }
-        }
-        throw JSONRPCError(RPC_WALLET_NOT_FOUND, "Requested wallet does not exist or is not loaded");
+        CWallet* pwallet = GetWallet(requestedWallet);
+        if (!pwallet) throw JSONRPCError(RPC_WALLET_NOT_FOUND, "Requested wallet does not exist or is not loaded");
+        return pwallet;
     }
-    return ::vpwallets.size() == 1 || (request.fHelp && ::vpwallets.size() > 0) ? ::vpwallets[0] : nullptr;
+
+    std::vector<CWallet*> wallets = GetWallets();
+    return wallets.size() == 1 || (request.fHelp && wallets.size() > 0) ? wallets[0] : nullptr;
 }
 
 std::string HelpRequiringPassphrase(CWallet * const pwallet)
@@ -67,7 +66,7 @@ bool EnsureWalletIsAvailable(CWallet * const pwallet, bool avoidException)
 {
     if (pwallet) return true;
     if (avoidException) return false;
-    if (::vpwallets.empty()) {
+    if (!HasWallets()) {
         // Note: It isn't currently possible to trigger this error because
         // wallet RPC methods aren't registered unless a wallet is loaded. But
         // this error is being kept as a precaution, because it's possible in
@@ -2862,8 +2861,7 @@ UniValue listwallets(const JSONRPCRequest& request)
 
     UniValue obj(UniValue::VARR);
 
-    for (CWalletRef pwallet : vpwallets) {
-
+    for (CWallet* pwallet : GetWallets()) {
         if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
             return NullUniValue;
         }
diff --git a/src/wallet/test/wallet_tests.cpp b/src/wallet/test/wallet_tests.cpp
index 57705926a3..99c963a348 100644
--- a/src/wallet/test/wallet_tests.cpp
+++ b/src/wallet/test/wallet_tests.cpp
@@ -74,7 +74,7 @@ BOOST_FIXTURE_TEST_CASE(rescan, TestChain100Setup)
     // after.
     {
         CWallet wallet("dummy", WalletDatabase::CreateDummy());
-        vpwallets.insert(vpwallets.begin(), &wallet);
+        AddWallet(&wallet);
         UniValue keys;
         keys.setArray();
         UniValue key;
@@ -105,7 +105,7 @@ BOOST_FIXTURE_TEST_CASE(rescan, TestChain100Setup)
                       "downloading and rescanning the relevant blocks (see -reindex and -rescan "
                       "options).\"}},{\"success\":true}]",
                               0, oldTip->GetBlockTimeMax(), TIMESTAMP_WINDOW));
-        vpwallets.erase(vpwallets.begin());
+        RemoveWallet(&wallet);
     }
 }
 
@@ -140,9 +140,9 @@ BOOST_FIXTURE_TEST_CASE(importwallet_rescan, TestChain100Setup)
         JSONRPCRequest request;
         request.params.setArray();
         request.params.push_back((pathTemp / "wallet.backup").string());
-        vpwallets.insert(vpwallets.begin(), &wallet);
+        AddWallet(&wallet);
         ::dumpwallet(request);
-        vpwallets.erase(vpwallets.begin());
+        RemoveWallet(&wallet);
     }
 
     // Call importwallet RPC and verify all blocks with timestamps >= BLOCK_TIME
@@ -153,9 +153,9 @@ BOOST_FIXTURE_TEST_CASE(importwallet_rescan, TestChain100Setup)
         JSONRPCRequest request;
         request.params.setArray();
         request.params.push_back((pathTemp / "wallet.backup").string());
-        vpwallets.insert(vpwallets.begin(), &wallet);
+        AddWallet(&wallet);
         ::importwallet(request);
-        vpwallets.erase(vpwallets.begin());
+        RemoveWallet(&wallet);
 
         LOCK(wallet.cs_wallet);
         BOOST_CHECK_EQUAL(wallet.mapWallet.size(), 3U);
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 45c85a7912..8c392434fc 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -28,12 +28,50 @@
 #include <utilmoneystr.h>
 #include <wallet/fees.h>
 
+#include <algorithm>
 #include <assert.h>
 #include <future>
 
 #include <boost/algorithm/string/replace.hpp>
 
-std::vector<CWalletRef> vpwallets;
+static std::vector<CWallet*> vpwallets;
+
+bool AddWallet(CWallet* wallet)
+{
+    assert(wallet);
+    std::vector<CWallet*>::const_iterator i = std::find(vpwallets.begin(), vpwallets.end(), wallet);
+    if (i != vpwallets.end()) return false;
+    vpwallets.push_back(wallet);
+    return true;
+}
+
+bool RemoveWallet(CWallet* wallet)
+{
+    assert(wallet);
+    std::vector<CWallet*>::iterator i = std::find(vpwallets.begin(), vpwallets.end(), wallet);
+    if (i == vpwallets.end()) return false;
+    vpwallets.erase(i);
+    return true;
+}
+
+bool HasWallets()
+{
+    return !vpwallets.empty();
+}
+
+std::vector<CWallet*> GetWallets()
+{
+    return vpwallets;
+}
+
+CWallet* GetWallet(const std::string& name)
+{
+    for (CWallet* wallet : vpwallets) {
+        if (wallet->GetName() == name) return wallet;
+    }
+    return nullptr;
+}
+
 /** Transaction fee set by the user */
 CFeeRate payTxFee(DEFAULT_TRANSACTION_FEE);
 unsigned int nTxConfirmTarget = DEFAULT_TX_CONFIRM_TARGET;
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index b85f374a06..dd165de825 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -32,8 +32,11 @@
 #include <utility>
 #include <vector>
 
-typedef CWallet* CWalletRef;
-extern std::vector<CWalletRef> vpwallets;
+bool AddWallet(CWallet* wallet);
+bool RemoveWallet(CWallet* wallet);
+bool HasWallets();
+std::vector<CWallet*> GetWallets();
+CWallet* GetWallet(const std::string& name);
 
 /**
  * Settings
@@ -268,7 +271,7 @@ public:
 //Get the marginal bytes of spending the specified output
 int CalculateMaximumSignedInputSize(const CTxOut& txout, const CWallet* pwallet);
 
-/** 
+/**
  * A transaction with a bunch of additional info that only the owner cares about.
  * It includes any unrecorded transactions needed to link it back to the block chain.
  */
@@ -653,7 +656,7 @@ struct CoinEligibilityFilter
 };
 
 class WalletRescanReserver; //forward declarations for ScanForWalletTransactions/RescanFromTime
-/** 
+/**
  * A CWallet is an extension of a keystore, which also maintains a set of transactions and balances,
  * and provides the ability to create new transactions.
  */
@@ -903,7 +906,7 @@ public:
     void GetKeyBirthTimes(std::map<CTxDestination, int64_t> &mapKeyBirth) const;
     unsigned int ComputeTimeSmart(const CWalletTx& wtx) const;
 
-    /** 
+    /**
      * Increment the next transaction order id
      * @return next transaction order id
      */
@@ -1032,7 +1035,7 @@ public:
     }
 
     void GetScriptForMining(std::shared_ptr<CReserveScript> &script);
-    
+
     unsigned int GetKeyPoolSize()
     {
         AssertLockHeld(cs_wallet); // set{Ex,In}ternalKeyPool
@@ -1057,7 +1060,7 @@ public:
     //! Flush wallet (bitdb flush)
     void Flush(bool shutdown=false);
 
-    /** 
+    /**
      * Address book entry changed.
      * @note called with lock cs_wallet held.
      */
@@ -1066,7 +1069,7 @@ public:
             const std::string &purpose,
             ChangeType status)> NotifyAddressBookChanged;
 
-    /** 
+    /**
      * Wallet transaction added, removed or updated.
      * @note called with lock cs_wallet held.
      */
@@ -1113,7 +1116,7 @@ public:
 
     /* Generates a new HD master key (will not be activated) */
     CPubKey GenerateNewHDMasterKey();
-    
+
     /* Set the current HD master key (will reset the chain child index counters)
        Sets the master key's version based on the current wallet version (so the
        caller must ensure the current wallet version is correct before calling
@@ -1184,7 +1187,7 @@ public:
 };
 
 
-/** 
+/**
  * DEPRECATED Account information.
  * Stored in wallet with key "acc"+string account name.
  */
@@ -1230,10 +1233,10 @@ std::vector<CTxDestination> GetAllDestinationsForKey(const CPubKey& key);
 class WalletRescanReserver
 {
 private:
-    CWalletRef m_wallet;
+    CWallet* m_wallet;
     bool m_could_reserve;
 public:
-    explicit WalletRescanReserver(CWalletRef w) : m_wallet(w), m_could_reserve(false) {}
+    explicit WalletRescanReserver(CWallet* w) : m_wallet(w), m_could_reserve(false) {}
 
     bool reserve()
     {
diff --git a/src/wallet/walletdb.cpp b/src/wallet/walletdb.cpp
index bcc7cf877d..5b275131af 100644
--- a/src/wallet/walletdb.cpp
+++ b/src/wallet/walletdb.cpp
@@ -756,7 +756,7 @@ void MaybeCompactWalletDB()
         return;
     }
 
-    for (CWalletRef pwallet : vpwallets) {
+    for (CWallet* pwallet : GetWallets()) {
         WalletDatabase& dbh = pwallet->GetDBHandle();
 
         unsigned int nUpdateCounter = dbh.nUpdateCounter;