Merge #19308: wallet: BerkeleyBatch Handle cursor internally

ca24edfbc1941ed0a3c9586416dae4e84794eb66 walletdb: Handle cursor internally (Andrew Chow)

Pull request description:

  Instead of returning a Dbc (BDB cursor object) and having the caller deal with the cursor, make BerkeleyBatch handle the cursor internally.

  Split from #18971

ACKs for top commit:
  ryanofsky:
    Code review ACK ca24edfbc1941ed0a3c9586416dae4e84794eb66. Changes since last review: StartCursor rename, moving CloseCursor calls near returns
  promag:
    Code review ACK ca24edfbc1941ed0a3c9586416dae4e84794eb66.

Tree-SHA512: f029b498c7f275aedca53ce7ade7cb99c82975fd6cad17346a4990fb3bcc54e2a5309b32053bd13def9ee464d331b036ac79abb8fc4fa561170c6cfc85283447

1 files changed, 15 insertions, 13 deletions

diff --git a/src/wallet/walletdb.cpp b/src/wallet/walletdb.cpp
index 603887ee58..ba5087e2e1 100644
--- a/src/wallet/walletdb.cpp
+++ b/src/wallet/walletdb.cpp
@@ -700,8 +700,7 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
         }
 
         // Get cursor
-        Dbc* pcursor = m_batch.GetCursor();
-        if (!pcursor)
+        if (!m_batch.StartCursor())
         {
             pwallet->WalletLogPrintf("Error getting wallet database cursor\n");
             return DBErrors::CORRUPT;
@@ -712,11 +711,14 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
             // Read next record
             CDataStream ssKey(SER_DISK, CLIENT_VERSION);
             CDataStream ssValue(SER_DISK, CLIENT_VERSION);
-            int ret = m_batch.ReadAtCursor(pcursor, ssKey, ssValue);
-            if (ret == DB_NOTFOUND)
+            bool complete;
+            bool ret = m_batch.ReadAtCursor(ssKey, ssValue, complete);
+            if (complete) {
                 break;
-            else if (ret != 0)
+            }
+            else if (!ret)
             {
+                m_batch.CloseCursor();
                 pwallet->WalletLogPrintf("Error reading next record from wallet database\n");
                 return DBErrors::CORRUPT;
             }
@@ -743,10 +745,10 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
             if (!strErr.empty())
                 pwallet->WalletLogPrintf("%s\n", strErr);
         }
-        pcursor->close();
     } catch (...) {
         result = DBErrors::CORRUPT;
     }
+    m_batch.CloseCursor();
 
     // Set the active ScriptPubKeyMans
     for (auto spk_man_pair : wss.m_active_external_spks) {
@@ -850,8 +852,7 @@ DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::list<CWal
         }
 
         // Get cursor
-        Dbc* pcursor = m_batch.GetCursor();
-        if (!pcursor)
+        if (!m_batch.StartCursor())
         {
             LogPrintf("Error getting wallet database cursor\n");
             return DBErrors::CORRUPT;
@@ -862,11 +863,12 @@ DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::list<CWal
             // Read next record
             CDataStream ssKey(SER_DISK, CLIENT_VERSION);
             CDataStream ssValue(SER_DISK, CLIENT_VERSION);
-            int ret = m_batch.ReadAtCursor(pcursor, ssKey, ssValue);
-            if (ret == DB_NOTFOUND)
+            bool complete;
+            bool ret = m_batch.ReadAtCursor(ssKey, ssValue, complete);
+            if (complete) {
                 break;
-            else if (ret != 0)
-            {
+            } else if (!ret) {
+                m_batch.CloseCursor();
                 LogPrintf("Error reading next record from wallet database\n");
                 return DBErrors::CORRUPT;
             }
@@ -881,10 +883,10 @@ DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::list<CWal
                 ssValue >> vWtx.back();
             }
         }
-        pcursor->close();
     } catch (...) {
         result = DBErrors::CORRUPT;
     }
+    m_batch.CloseCursor();
 
     return result;
 }