[wallet] Add CWallet::Verify function

This allows a single wallet to be verified. Prior to this commit, all
wallets were verified together by the WalletInit::Verify() function at
start-up.

Individual wallet verification will be done when loading wallets
dynamically at runtime.

Author: jnewbery

src/wallet/init.cpp

@@ -190,55 +190,24 @@ bool WalletInit::Verify() const
 
     uiInterface.InitMessage(_("Verifying wallet(s)..."));
 
+    std::vector<std::string> wallet_files = gArgs.GetArgs("-wallet");
+
+    // Parameter interaction code should have thrown an error if -salvagewallet
+    // was enabled with more than wallet file, so the wallet_files size check
+    // here should have no effect.
+    bool salvage_wallet = gArgs.GetBoolArg("-salvagewallet", false) && wallet_files.size() <= 1;
+
     // Keep track of each wallet absolute path to detect duplicates.
     std::set<fs::path> wallet_paths;
 
-    for (const std::string& walletFile : gArgs.GetArgs("-wallet")) {
-        // Do some checking on wallet path. It should be either a:
-        //
-        // 1. Path where a directory can be created.
-        // 2. Path to an existing directory.
-        // 3. Path to a symlink to a directory.
-        // 4. For backwards compatibility, the name of a data file in -walletdir.
-        fs::path wallet_path = fs::absolute(walletFile, GetWalletDir());
-        fs::file_type path_type = fs::symlink_status(wallet_path).type();
-        if (!(path_type == fs::file_not_found || path_type == fs::directory_file ||
-              (path_type == fs::symlink_file && fs::is_directory(wallet_path)) ||
-              (path_type == fs::regular_file && fs::path(walletFile).filename() == walletFile))) {
-            return InitError(strprintf(
-                _("Invalid -wallet path '%s'. -wallet path should point to a directory where wallet.dat and "
-                  "database/log.?????????? files can be stored, a location where such a directory could be created, "
-                  "or (for backwards compatibility) the name of an existing data file in -walletdir (%s)"),
-                walletFile, GetWalletDir()));
-        }
+    for (const auto wallet_file : wallet_files) {
+        fs::path wallet_path = fs::absolute(wallet_file, GetWalletDir());
 
         if (!wallet_paths.insert(wallet_path).second) {
-            return InitError(strprintf(_("Error loading wallet %s. Duplicate -wallet filename specified."), walletFile));
-        }
-
-        std::string strError;
-        if (!WalletBatch::VerifyEnvironment(wallet_path, strError)) {
-            return InitError(strError);
+            return InitError(strprintf(_("Error loading wallet %s. Duplicate -wallet filename specified."), wallet_file));
         }
 
-        if (gArgs.GetBoolArg("-salvagewallet", false)) {
-            // Recover readable keypairs:
-            CWallet dummyWallet("dummy", WalletDatabase::CreateDummy());
-            std::string backup_filename;
-            if (!WalletBatch::Recover(wallet_path, (void *)&dummyWallet, WalletBatch::RecoverKeysOnlyFilter, backup_filename)) {
-                return false;
-            }
-        }
-
-        std::string strWarning;
-        bool dbV = WalletBatch::VerifyDatabaseFile(wallet_path, strWarning, strError);
-        if (!strWarning.empty()) {
-            InitWarning(strWarning);
-        }
-        if (!dbV) {
-            InitError(strError);
-            return false;
-        }
+        if (!CWallet::Verify(wallet_file, salvage_wallet)) return false;
     }
 
     return true;

src/wallet/wallet.cpp

@@ -27,6 +27,7 @@
 #include <txmempool.h>
 #include <utilmoneystr.h>
 #include <wallet/fees.h>
+#include <wallet/walletutil.h>
 
 #include <algorithm>
 #include <assert.h>
@@ -3989,6 +3990,61 @@ void CWallet::MarkPreSplitKeys()
     }
 }
 
+bool CWallet::Verify(std::string wallet_file, bool salvage_wallet)
+{
+    // Do some checking on wallet path. It should be either a:
+    //
+    // 1. Path where a directory can be created.
+    // 2. Path to an existing directory.
+    // 3. Path to a symlink to a directory.
+    // 4. For backwards compatibility, the name of a data file in -walletdir.
+    LOCK(cs_wallets);
+    fs::path wallet_path = fs::absolute(wallet_file, GetWalletDir());
+    fs::file_type path_type = fs::symlink_status(wallet_path).type();
+    if (!(path_type == fs::file_not_found || path_type == fs::directory_file ||
+          (path_type == fs::symlink_file && fs::is_directory(wallet_path)) ||
+          (path_type == fs::regular_file && fs::path(wallet_file).filename() == wallet_file))) {
+        return InitError(strprintf(
+            _("Invalid -wallet path '%s'. -wallet path should point to a directory where wallet.dat and "
+              "database/log.?????????? files can be stored, a location where such a directory could be created, "
+              "or (for backwards compatibility) the name of an existing data file in -walletdir (%s)"),
+            wallet_file, GetWalletDir()));
+    }
+
+    // Make sure that the wallet path doesn't clash with an existing wallet path
+    for (auto wallet : GetWallets()) {
+        if (fs::absolute(wallet->GetName(), GetWalletDir()) == wallet_path) {
+            return InitError(strprintf(_("Error loading wallet %s. Duplicate -wallet filename specified."), wallet_file));
+        }
+    }
+
+    std::string strError;
+    if (!WalletBatch::VerifyEnvironment(wallet_path, strError)) {
+        return InitError(strError);
+    }
+
+    if (salvage_wallet) {
+        // Recover readable keypairs:
+        CWallet dummyWallet("dummy", WalletDatabase::CreateDummy());
+        std::string backup_filename;
+        if (!WalletBatch::Recover(wallet_path, (void *)&dummyWallet, WalletBatch::RecoverKeysOnlyFilter, backup_filename)) {
+            return false;
+        }
+    }
+
+    std::string strWarning;
+    bool dbV = WalletBatch::VerifyDatabaseFile(wallet_path, strWarning, strError);
+    if (!strWarning.empty()) {
+        InitWarning(strWarning);
+    }
+    if (!dbV) {
+        InitError(strError);
+        return false;
+    }
+
+    return true;
+}
+
 CWallet* CWallet::CreateWalletFromFile(const std::string& name, const fs::path& path)
 {
     const std::string& walletFile = name;

src/wallet/wallet.h

@@ -1118,6 +1118,9 @@ class CWallet final : public CCryptoKeyStore, public CValidationInterface
     /** Mark a transaction as replaced by another transaction (e.g., BIP 125). */
     bool MarkReplaced(const uint256& originalHash, const uint256& newHash);
 
+    //! Verify wallet naming and perform salvage on the wallet if required
+    static bool Verify(std::string wallet_file, bool salvage_wallet);
+
     /* Initializes the wallet, returns a new CWallet instance or a null pointer in case of an error */
     static CWallet* CreateWalletFromFile(const std::string& name, const fs::path& path);