From e5637b1dcaf6282e159dce5299a6a365df20454c Mon Sep 17 00:00:00 2001
From: Glenn Willen <gwillen@nerdnet.org>
Date: Tue, 26 Feb 2019 18:00:10 -0800
Subject: [PATCH] wallet: Improve log output for errors during load

When loading the default wallet, display the wallet name in error messages as
"[default wallet]", instead of the empty string which gives confusing messages.

When an exception occurs during wallet loading, display e.what() if possible,
instead of nothing.
---
 src/wallet/wallet.cpp   | 16 ++++++++--------
 src/wallet/walletdb.cpp |  9 +++++++++
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 388422bec84d39..03d3c56caaa93e 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -4097,7 +4097,7 @@ bool CWallet::Verify(interfaces::Chain& chain, const WalletLocation& location, b
 
 std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain, const WalletLocation& location, uint64_t wallet_creation_flags)
 {
-    const std::string& walletFile = location.GetName();
+    const std::string& log_wallet_name = location.GetName().empty() ? "[default wallet]" : location.GetName();
 
     // needed to restore wallet transaction meta data after -zapwallettxes
     std::vector<CWalletTx> vWtx;
@@ -4108,7 +4108,7 @@ std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain,
         std::unique_ptr<CWallet> tempWallet = MakeUnique<CWallet>(chain, location, WalletDatabase::Create(location.GetPath()));
         DBErrors nZapWalletRet = tempWallet->ZapWalletTx(vWtx);
         if (nZapWalletRet != DBErrors::LOAD_OK) {
-            InitError(strprintf(_("Error loading %s: Wallet corrupted"), walletFile));
+            InitError(strprintf(_("Error loading %s: Wallet corrupted"), log_wallet_name));
             return nullptr;
         }
     }
@@ -4124,17 +4124,17 @@ std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain,
     if (nLoadWalletRet != DBErrors::LOAD_OK)
     {
         if (nLoadWalletRet == DBErrors::CORRUPT) {
-            InitError(strprintf(_("Error loading %s: Wallet corrupted"), walletFile));
+            InitError(strprintf(_("Error loading %s: Wallet corrupted"), log_wallet_name));
             return nullptr;
         }
         else if (nLoadWalletRet == DBErrors::NONCRITICAL_ERROR)
         {
             InitWarning(strprintf(_("Error reading %s! All keys read correctly, but transaction data"
                                          " or address book entries might be missing or incorrect."),
-                walletFile));
+                log_wallet_name));
         }
         else if (nLoadWalletRet == DBErrors::TOO_NEW) {
-            InitError(strprintf(_("Error loading %s: Wallet requires newer version of %s"), walletFile, _(PACKAGE_NAME)));
+            InitError(strprintf(_("Error loading %s: Wallet requires newer version of %s"), log_wallet_name, _(PACKAGE_NAME)));
             return nullptr;
         }
         else if (nLoadWalletRet == DBErrors::NEED_REWRITE)
@@ -4143,7 +4143,7 @@ std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain,
             return nullptr;
         }
         else {
-            InitError(strprintf(_("Error loading %s"), walletFile));
+            InitError(strprintf(_("Error loading %s"), log_wallet_name));
             return nullptr;
         }
     }
@@ -4235,12 +4235,12 @@ std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain,
         walletInstance->ChainStateFlushed(locked_chain->getTipLocator());
     } else if (wallet_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS) {
         // Make it impossible to disable private keys after creation
-        InitError(strprintf(_("Error loading %s: Private keys can only be disabled during creation"), walletFile));
+        InitError(strprintf(_("Error loading %s: Private keys can only be disabled during creation"), log_wallet_name));
         return NULL;
     } else if (walletInstance->IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
         LOCK(walletInstance->cs_KeyStore);
         if (!walletInstance->mapKeys.empty() || !walletInstance->mapCryptedKeys.empty()) {
-            InitWarning(strprintf(_("Warning: Private keys detected in wallet {%s} with disabled private keys"), walletFile));
+            InitWarning(strprintf(_("Warning: Private keys detected in wallet {%s} with disabled private keys"), log_wallet_name));
         }
     }
 
diff --git a/src/wallet/walletdb.cpp b/src/wallet/walletdb.cpp
index 2783f83fd6070a..bb46ec03934cd2 100644
--- a/src/wallet/walletdb.cpp
+++ b/src/wallet/walletdb.cpp
@@ -422,8 +422,17 @@ ReadKeyValue(CWallet* pwallet, CDataStream& ssKey, CDataStream& ssValue,
                 strType != "minversion" && strType != "acentry") {
             wss.m_unknown_records++;
         }
+    } catch (const std::exception& e)
+    {
+        if (strErr.empty()) {
+            strErr = e.what();
+        }
+        return false;
     } catch (...)
     {
+        if (strErr.empty()) {
+            strErr = "Caught unknown exception in ReadKeyValue";
+        }
         return false;
     }
     return true;