wallet: scan SQLite wallet records

4 files changed, 66 insertions, 1 deletions

diff --git a/docs/storage.md b/docs/storage.md
index bb414b5..2d748fa 100644
--- a/docs/storage.md
+++ b/docs/storage.md
@@ -108,7 +108,9 @@ BDB-to-SQLite migration or runtime backend flag exists.
 `wallet.dat` record through `ScanWalletRecords()` and writes those same key and
 value bytes into the SQLite table inside one transaction. It refuses to
 overwrite an existing export and still does not change the runtime wallet
-backend.
+backend. `CWalletDBSQLite::ScanRecords()` can stream those exported records back
+through the same visitor shape, so tests can compare BDB and SQLite record
+streams without introducing a SQLite runtime wallet loader yet.
 
 ## `blkindex.dat`
 
diff --git a/src/selftest.cpp b/src/selftest.cpp
index 7a54271..408dd41 100644
--- a/src/selftest.cpp
+++ b/src/selftest.cpp
@@ -1259,6 +1259,12 @@ static int RunWalletSQLiteMigrationSelfTest()
         }
         nFail += Check(fAllMatch,
                        "SQLite export preserves every wallet.dat key/value byte-for-byte") ? 0 : 1;
+
+        std::map<vector<unsigned char>, vector<unsigned char> > mapSQLite;
+        CWalletRecordMapVisitor sqliteVisitor(mapSQLite);
+        nFail += Check(db.ScanRecords(sqliteVisitor, strError) &&
+                       mapSQLite == mapBDB,
+                       "SQLite wallet scanner streams every exported record byte-for-byte") ? 0 : 1;
     }
     catch (const std::exception& e)
     {
diff --git a/src/wallet_sqlite.cpp b/src/wallet_sqlite.cpp
index 4369af6..8489cac 100644
--- a/src/wallet_sqlite.cpp
+++ b/src/wallet_sqlite.cpp
@@ -231,6 +231,60 @@ bool CWalletDBSQLite::ReadRecord(const vector<unsigned char>& vchKey,
     return false;
 }
 
+bool CWalletDBSQLite::ScanRecords(CWalletRecordVisitor& visitor,
+                                  string& strError)
+{
+    if (!pdb)
+    {
+        strError = "SQLite wallet is not open";
+        return false;
+    }
+
+    sqlite3_stmt* stmt = NULL;
+    const char* pszSql = "SELECT key, value FROM wallet_records ORDER BY rowid;";
+    int ret = sqlite3_prepare_v2(pdb, pszSql, -1, &stmt, NULL);
+    if (ret != SQLITE_OK)
+    {
+        SetSQLiteError(pdb, "cannot prepare SQLite wallet scan", strError);
+        return false;
+    }
+
+    while ((ret = sqlite3_step(stmt)) == SQLITE_ROW)
+    {
+        const unsigned char* pchKey =
+            (const unsigned char*)sqlite3_column_blob(stmt, 0);
+        int nKeyBytes = sqlite3_column_bytes(stmt, 0);
+        const unsigned char* pchValue =
+            (const unsigned char*)sqlite3_column_blob(stmt, 1);
+        int nValueBytes = sqlite3_column_bytes(stmt, 1);
+
+        vector<unsigned char> vchKey;
+        vector<unsigned char> vchValue;
+        if (nKeyBytes > 0 && pchKey)
+            vchKey.assign(pchKey, pchKey + nKeyBytes);
+        if (nValueBytes > 0 && pchValue)
+            vchValue.assign(pchValue, pchValue + nValueBytes);
+
+        CDataStream ssKey(vchKey, SER_DISK);
+        CDataStream ssValue(vchValue, SER_DISK);
+        if (!visitor.VisitWalletRecord(ssKey, ssValue, strError))
+        {
+            sqlite3_finalize(stmt);
+            return false;
+        }
+    }
+
+    if (ret != SQLITE_DONE)
+    {
+        SetSQLiteError(pdb, "cannot scan SQLite wallet records", strError);
+        sqlite3_finalize(stmt);
+        return false;
+    }
+
+    sqlite3_finalize(stmt);
+    return true;
+}
+
 bool CWalletDBSQLite::CountRecords(int& nRecordsRet, string& strError)
 {
     nRecordsRet = 0;
diff --git a/src/wallet_sqlite.h b/src/wallet_sqlite.h
index 5ef862d..385a340 100644
--- a/src/wallet_sqlite.h
+++ b/src/wallet_sqlite.h
@@ -6,6 +6,8 @@
 
 #include <sqlite3.h>
 
+class CWalletRecordVisitor;
+
 class CWalletDBSQLite
 {
 public:
@@ -26,6 +28,7 @@ public:
     bool ReadRecord(const vector<unsigned char>& vchKey,
                     vector<unsigned char>& vchValueRet,
                     string& strError);
+    bool ScanRecords(CWalletRecordVisitor& visitor, string& strError);
     bool CountRecords(int& nRecordsRet, string& strError);
 
 private: