[qt] Move some WalletModel functions into CWallet

Motivation for moving these is to make supporting IPC simpler (#10102), so
these lookups can be one-shot IPC requests, instead of back-and-forth
interactions over the IPC channel.

Also these functions are potentially useful outside of the bitcoin GUI (e.g.
for RPCs).

src/qt/walletmodel.cpp

@@ -63,14 +63,7 @@ CAmount WalletModel::getBalance(const CCoinControl *coinControl) const
 {
     if (coinControl)
     {
-        CAmount nBalance = 0;
-        std::vector<COutput> vCoins;
-        wallet->AvailableCoins(vCoins, true, coinControl);
-        BOOST_FOREACH(const COutput& out, vCoins)
-            if(out.fSpendable)
-                nBalance += out.tx->tx->vout[out.i].nValue;
-
-        return nBalance;
+        return wallet->GetAvailableBalance(coinControl);
     }
 
     return wallet->GetBalance();
@@ -595,38 +588,11 @@ bool WalletModel::isSpent(const COutPoint& outpoint) const
 // AvailableCoins + LockedCoins grouped by wallet address (put change in one group with wallet address)
 void WalletModel::listCoins(std::map<QString, std::vector<COutput> >& mapCoins) const
 {
-    std::vector<COutput> vCoins;
-    wallet->AvailableCoins(vCoins);
-
-    LOCK2(cs_main, wallet->cs_wallet); // ListLockedCoins, mapWallet
-    std::vector<COutPoint> vLockedCoins;
-    wallet->ListLockedCoins(vLockedCoins);
-
-    // add locked coins
-    BOOST_FOREACH(const COutPoint& outpoint, vLockedCoins)
-    {
-        if (!wallet->mapWallet.count(outpoint.hash)) continue;
-        int nDepth = wallet->mapWallet[outpoint.hash].GetDepthInMainChain();
-        if (nDepth < 0) continue;
-        COutput out(&wallet->mapWallet[outpoint.hash], outpoint.n, nDepth, true /* spendable */, true /* solvable */, true /* safe */);
-        if (outpoint.n < out.tx->tx->vout.size() && wallet->IsMine(out.tx->tx->vout[outpoint.n]) == ISMINE_SPENDABLE)
-            vCoins.push_back(out);
-    }
-
-    BOOST_FOREACH(const COutput& out, vCoins)
-    {
-        COutput cout = out;
-
-        while (wallet->IsChange(cout.tx->tx->vout[cout.i]) && cout.tx->tx->vin.size() > 0 && wallet->IsMine(cout.tx->tx->vin[0]))
-        {
-            if (!wallet->mapWallet.count(cout.tx->tx->vin[0].prevout.hash)) break;
-            cout = COutput(&wallet->mapWallet[cout.tx->tx->vin[0].prevout.hash], cout.tx->tx->vin[0].prevout.n, 0 /* depth */, true /* spendable */, true /* solvable */, true /* safe */);
+    for (auto& group : wallet->ListCoins()) {
+        auto& resultGroup = mapCoins[QString::fromStdString(CBitcoinAddress(group.first).ToString())];
+        for (auto& coin : group.second) {
+            resultGroup.emplace_back(std::move(coin));
         }
-
-        CTxDestination address;
-        if(!out.fSpendable || !ExtractDestination(cout.tx->tx->vout[cout.i].scriptPubKey, address))
-            continue;
-        mapCoins[QString::fromStdString(CBitcoinAddress(address).ToString())].push_back(out);
     }
 }
 
@@ -656,11 +622,7 @@ void WalletModel::listLockedCoins(std::vector<COutPoint>& vOutpts)
 
 void WalletModel::loadReceiveRequests(std::vector<std::string>& vReceiveRequests)
 {
-    LOCK(wallet->cs_wallet);
-    BOOST_FOREACH(const PAIRTYPE(CTxDestination, CAddressBookData)& item, wallet->mapAddressBook)
-        BOOST_FOREACH(const PAIRTYPE(std::string, std::string)& item2, item.second.destdata)
-            if (item2.first.size() > 2 && item2.first.substr(0,2) == "rr") // receive request
-                vReceiveRequests.push_back(item2.second);
+    vReceiveRequests = wallet->GetDestValues("rr"); // receive request
 }
 
 bool WalletModel::saveReceiveRequest(const std::string &sAddress, const int64_t nId, const std::string &sRequest)
@@ -680,11 +642,7 @@ bool WalletModel::saveReceiveRequest(const std::string &sAddress, const int64_t
 
 bool WalletModel::transactionCanBeAbandoned(uint256 hash) const
 {
-    LOCK2(cs_main, wallet->cs_wallet);
-    const CWalletTx *wtx = wallet->GetWalletTx(hash);
-    if (!wtx || wtx->isAbandoned() || wtx->GetDepthInMainChain() > 0 || wtx->InMempool())
-        return false;
-    return true;
+    return wallet->TransactionCanBeAbandoned(hash);
 }
 
 bool WalletModel::abandonTransaction(uint256 hash) const

src/wallet/wallet.cpp

@@ -982,6 +982,13 @@ bool CWallet::AddToWalletIfInvolvingMe(const CTransactionRef& ptx, const CBlockI
     return false;
 }
 
+bool CWallet::TransactionCanBeAbandoned(const uint256& hashTx) const
+{
+    LOCK2(cs_main, cs_wallet);
+    const CWalletTx* wtx = GetWalletTx(hashTx);
+    return wtx && !wtx->isAbandoned() && wtx->GetDepthInMainChain() <= 0 && !wtx->InMempool();
+}
+
 bool CWallet::AbandonTransaction(const uint256& hashTx)
 {
     LOCK2(cs_main, cs_wallet);
@@ -1977,6 +1984,19 @@ CAmount CWallet::GetLegacyBalance(const isminefilter& filter, int minDepth, cons
     return balance;
 }
 
+CAmount CWallet::GetAvailableBalance(const CCoinControl* coinControl) const
+{
+    CAmount balance = 0;
+    std::vector<COutput> vCoins;
+    AvailableCoins(vCoins, true, coinControl);
+    for (const COutput& out : vCoins) {
+        if (out.fSpendable) {
+            balance += out.tx->tx->vout[out.i].nValue;
+        }
+    }
+    return balance;
+}
+
 void CWallet::AvailableCoins(std::vector<COutput> &vCoins, bool fOnlySafe, const CCoinControl *coinControl, const CAmount &nMinimumAmount, const CAmount &nMaximumAmount, const CAmount &nMinimumSumAmount, const uint64_t &nMaximumCount, const int &nMinDepth, const int &nMaxDepth) const
 {
     vCoins.clear();
@@ -2088,6 +2108,69 @@ void CWallet::AvailableCoins(std::vector<COutput> &vCoins, bool fOnlySafe, const
     }
 }
 
+std::map<CTxDestination, std::vector<COutput>> CWallet::ListCoins() const
+{
+    // TODO: Add AssertLockHeld(cs_wallet) here.
+    //
+    // Because the return value from this function contains pointers to
+    // CWalletTx objects, callers to this function really should acquire the
+    // cs_wallet lock before calling it. However, the current caller doesn't
+    // acquire this lock yet. There was an attempt to add the missing lock in
+    // https://github.com/bitcoin/bitcoin/pull/10340, but that change has been
+    // postponed until after https://github.com/bitcoin/bitcoin/pull/10244 to
+    // avoid adding some extra complexity to the Qt code.
+
+    std::map<CTxDestination, std::vector<COutput>> result;
+
+    std::vector<COutput> availableCoins;
+    AvailableCoins(availableCoins);
+
+    LOCK2(cs_main, cs_wallet);
+    for (auto& coin : availableCoins) {
+        CTxDestination address;
+        if (coin.fSpendable &&
+            ExtractDestination(FindNonChangeParentOutput(*coin.tx->tx, coin.i).scriptPubKey, address)) {
+            result[address].emplace_back(std::move(coin));
+        }
+    }
+
+    std::vector<COutPoint> lockedCoins;
+    ListLockedCoins(lockedCoins);
+    for (const auto& output : lockedCoins) {
+        auto it = mapWallet.find(output.hash);
+        if (it != mapWallet.end()) {
+            int depth = it->second.GetDepthInMainChain();
+            if (depth >= 0 && output.n < it->second.tx->vout.size() &&
+                IsMine(it->second.tx->vout[output.n]) == ISMINE_SPENDABLE) {
+                CTxDestination address;
+                if (ExtractDestination(FindNonChangeParentOutput(*it->second.tx, output.n).scriptPubKey, address)) {
+                    result[address].emplace_back(
+                        &it->second, output.n, depth, true /* spendable */, true /* solvable */, false /* safe */);
+                }
+            }
+        }
+    }
+
+    return result;
+}
+
+const CTxOut& CWallet::FindNonChangeParentOutput(const CTransaction& tx, int output) const
+{
+    const CTransaction* ptx = &tx;
+    int n = output;
+    while (IsChange(ptx->vout[n]) && ptx->vin.size() > 0) {
+        const COutPoint& prevout = ptx->vin[0].prevout;
+        auto it = mapWallet.find(prevout.hash);
+        if (it == mapWallet.end() || it->second.tx->vout.size() <= prevout.n ||
+            !IsMine(it->second.tx->vout[prevout.n])) {
+            break;
+        }
+        ptx = it->second.tx.get();
+        n = prevout.n;
+    }
+    return ptx->vout[n];
+}
+
 static void ApproximateBestSubset(const std::vector<CInputCoin>& vValue, const CAmount& nTotalLower, const CAmount& nTargetValue,
                                   std::vector<char>& vfBest, CAmount& nBest, int iterations = 1000)
 {
@@ -3408,7 +3491,7 @@ bool CWallet::IsLockedCoin(uint256 hash, unsigned int n) const
     return (setLockedCoins.count(outpt) > 0);
 }
 
-void CWallet::ListLockedCoins(std::vector<COutPoint>& vOutpts)
+void CWallet::ListLockedCoins(std::vector<COutPoint>& vOutpts) const
 {
     AssertLockHeld(cs_wallet); // setLockedCoins
     for (std::set<COutPoint>::iterator it = setLockedCoins.begin();
@@ -3609,6 +3692,20 @@ bool CWallet::GetDestData(const CTxDestination &dest, const std::string &key, st
     return false;
 }
 
+std::vector<std::string> CWallet::GetDestValues(const std::string& prefix) const
+{
+    LOCK(cs_wallet);
+    std::vector<std::string> values;
+    for (const auto& address : mapAddressBook) {
+        for (const auto& data : address.second.destdata) {
+            if (!data.first.compare(0, prefix.size(), prefix)) {
+                values.emplace_back(data.second);
+            }
+        }
+    }
+    return values;
+}
+
 std::string CWallet::GetWalletHelpString(bool showDebug)
 {
     std::string strUsage = HelpMessageGroup(_("Wallet options:"));

src/wallet/wallet.h

@@ -820,6 +820,16 @@ public:
      */
     void AvailableCoins(std::vector<COutput>& vCoins, bool fOnlySafe=true, const CCoinControl *coinControl = NULL, const CAmount& nMinimumAmount = 1, const CAmount& nMaximumAmount = MAX_MONEY, const CAmount& nMinimumSumAmount = MAX_MONEY, const uint64_t& nMaximumCount = 0, const int& nMinDepth = 0, const int& nMaxDepth = 9999999) const;
 
+    /**
+     * Return list of available coins and locked coins grouped by non-change output address.
+     */
+    std::map<CTxDestination, std::vector<COutput>> ListCoins() const;
+
+    /**
+     * Find non-change parent output.
+     */
+    const CTxOut& FindNonChangeParentOutput(const CTransaction& tx, int output) const;
+
     /**
      * Shuffle and select coins until nTargetValue is reached while avoiding
      * small change; This method is stochastic for some inputs and upon
@@ -834,7 +844,7 @@ public:
     void LockCoin(const COutPoint& output);
     void UnlockCoin(const COutPoint& output);
     void UnlockAllCoins();
-    void ListLockedCoins(std::vector<COutPoint>& vOutpts);
+    void ListLockedCoins(std::vector<COutPoint>& vOutpts) const;
 
     /*
      * Rescan abort properties
@@ -873,6 +883,8 @@ public:
     bool LoadDestData(const CTxDestination &dest, const std::string &key, const std::string &value);
     //! Look up a destination data tuple in the store, return true if found false otherwise
     bool GetDestData(const CTxDestination &dest, const std::string &key, std::string *value) const;
+    //! Get all destination values matching a prefix.
+    std::vector<std::string> GetDestValues(const std::string& prefix) const;
 
     //! Adds a watch-only address to the store, and saves it to disk.
     bool AddWatchOnly(const CScript& dest, int64_t nCreateTime);
@@ -917,6 +929,7 @@ public:
     CAmount GetUnconfirmedWatchOnlyBalance() const;
     CAmount GetImmatureWatchOnlyBalance() const;
     CAmount GetLegacyBalance(const isminefilter& filter, int minDepth, const std::string* account) const;
+    CAmount GetAvailableBalance(const CCoinControl* coinControl = nullptr) const;
 
     /**
      * Insert additional inputs into the transaction by
@@ -1066,6 +1079,9 @@ public:
     /** Set whether this wallet broadcasts transactions. */
     void SetBroadcastTransactions(bool broadcast) { fBroadcastTransactions = broadcast; }
 
+    /** Return whether transaction can be abandoned */
+    bool TransactionCanBeAbandoned(const uint256& hashTx) const;
+
     /* Mark a transaction (and it in-wallet descendants) as abandoned so its inputs may be respent. */
     bool AbandonTransaction(const uint256& hashTx);