Merge bitcoin/bitcoin#28186: kernel: Prune leveldb headers

d8f1222ac50f089a0af29eaf8ce0555bad8366ef refactor: Correct dbwrapper key naming (TheCharlatan)
be8f159ac59b9e700cbd3314ed71ebf39bd5b67a build: Remove leveldb from BITCOIN_INCLUDES (TheCharlatan)
c95b37d641b1eed4a62d55ca5342a6ed8c7a1ce7 refactor: Move CDBWrapper leveldb members to their own context struct (TheCharlatan)
c534a615e93452a5f509aaf5f68c600391a98d6a refactor: Split dbwrapper CDBWrapper::EstimateSize implementation (TheCharlatan)
586448888b72f7c87db4dcd30fc4e4044afae13b refactor: Move HandleError to dbwrapper implementation (TheCharlatan)
dede0eef7adb7413f62f5abd68cac8e01635ba4a refactor: Split dbwrapper CDBWrapper::Exists implementation (TheCharlatan)
a5c2eb57484314b04ec94523d14e0ef0c6c46d4f refactor: Fix logging.h includes (TheCharlatan)
84058e0eed9c05bc30984b39131e88ad1425628f refactor: Split dbwrapper CDBWrapper::Read implementation (TheCharlatan)
e4af2408f2ac59788567b6fc8cb3a68fc43da9fe refactor: Pimpl leveldb::Iterator for CDBIterator (TheCharlatan)
ef941ff1281e76308c3e746e592375bec023e9e4 refactor: Split dbwrapper CDBIterator::GetValue implementation (TheCharlatan)
b7a1ab5cb4e60230f62c94efb3a10d07c9af4883 refactor: Split dbwrapper CDBIterator::GetKey implementation (TheCharlatan)
d7437908cdf242626263ba9d5541addcddadc594 refactor: Split dbwrapper CDBIterator::Seek implementation (TheCharlatan)
ea8135de7e617259cda3fc7b1c8e7569d454fd57 refactor: Pimpl leveldb::batch for CDBBatch (TheCharlatan)
b9870c920dc475ec759eaf7339ea42aecba92138 refactor: Split dbwrapper CDBatch::Erase implementation (TheCharlatan)
532ee812a499e13b123af6b8415d8de1f3804f0f refactor: Split dbwrapper CDBBatch::Write implementation (TheCharlatan)
afc534df9adbf5599b286b5dc3531a4b9ac2d056 refactor: Wrap DestroyDB in dbwrapper helper (TheCharlatan)

Pull request description:

  Leveldb headers are currently included in the `dbwrapper.h` file and thus available to many of Bitcoin Core's source files. However, leveldb-specific functionality should be abstracted by the `dbwrapper` and does not need to be available to the rest of the code. Having leveldb included in a widely-used header such as `dbwrapper.h` bloats the entire project's header tree.

  The `dbwrapper` is a key component of the libbitcoinkernel library. Future users of this library would not want to contend with  having the leveldb headers exposed and potentially polluting their project's namespace.

  For these reasons, the leveldb headers are removed from the `dbwrapper` by moving leveldb-specific code to the implementation file and creating a [pimpl](https://en.cppreference.com/w/cpp/language/pimpl) where leveldb member variables are indispensable. As a final step, the leveldb include flags are removed from the `BITCOIN_INCLUDES` and moved to places where the dbwrapper is compiled.

  ---

  This pull request is part of the [libbitcoinkernel project](https://github.com/bitcoin/bitcoin/issues/27587), and more specifically its stage 1 step 3 "Decouple most non-consensus headers from libbitcoinkernel".

ACKs for top commit:
  stickies-v:
    re-ACK https://github.com/bitcoin/bitcoin/commit/d8f1222ac50f089a0af29eaf8ce0555bad8366ef
  MarcoFalke:
    ACK d8f1222ac50f089a0af29eaf8ce0555bad8366ef  🔠

Tree-SHA512: 0f58309be165af0162e648233451cd80fda88726fc10c0da7bfe4ec2ffa9afe63fbf7ffae9493698d3f39653b4ad870c372eee652ecc90ab1c29d86c387070f3

15 files changed, 254 insertions, 159 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index b48d723bc9..a108e60c86 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -24,7 +24,7 @@ check_PROGRAMS =
 TESTS =
 BENCHMARKS =
 
-BITCOIN_INCLUDES=-I$(builddir) -I$(srcdir)/$(MINISKETCH_INCLUDE_DIR_INT) -I$(srcdir)/secp256k1/include -I$(srcdir)/$(UNIVALUE_INCLUDE_DIR_INT) $(LEVELDB_CPPFLAGS)
+BITCOIN_INCLUDES=-I$(builddir) -I$(srcdir)/$(MINISKETCH_INCLUDE_DIR_INT) -I$(srcdir)/secp256k1/include -I$(srcdir)/$(UNIVALUE_INCLUDE_DIR_INT)
 
 LIBBITCOIN_NODE=libbitcoin_node.a
 LIBBITCOIN_COMMON=libbitcoin_common.a
@@ -370,7 +370,7 @@ obj/build.h: FORCE
 libbitcoin_util_a-clientversion.$(OBJEXT): obj/build.h
 
 # node #
-libbitcoin_node_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) $(BOOST_CPPFLAGS) $(MINIUPNPC_CPPFLAGS) $(NATPMP_CPPFLAGS) $(EVENT_CFLAGS) $(EVENT_PTHREADS_CFLAGS)
+libbitcoin_node_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) $(LEVELDB_CPPFLAGS) $(BOOST_CPPFLAGS) $(MINIUPNPC_CPPFLAGS) $(NATPMP_CPPFLAGS) $(EVENT_CFLAGS) $(EVENT_PTHREADS_CFLAGS)
 libbitcoin_node_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_node_a_SOURCES = \
   addrdb.cpp \
diff --git a/src/blockencodings.cpp b/src/blockencodings.cpp
index 9aa0a6ba20..211b4740be 100644
--- a/src/blockencodings.cpp
+++ b/src/blockencodings.cpp
@@ -9,6 +9,7 @@
 #include <consensus/validation.h>
 #include <crypto/sha256.h>
 #include <crypto/siphash.h>
+#include <logging.h>
 #include <random.h>
 #include <streams.h>
 #include <txmempool.h>
diff --git a/src/dbwrapper.cpp b/src/dbwrapper.cpp
index 7cf6bef90f..c95937ba75 100644
--- a/src/dbwrapper.cpp
+++ b/src/dbwrapper.cpp
@@ -4,9 +4,12 @@
 
 #include <dbwrapper.h>
 
+#include <clientversion.h>
 #include <logging.h>
 #include <random.h>
-#include <tinyformat.h>
+#include <serialize.h>
+#include <span.h>
+#include <streams.h>
 #include <util/fs.h>
 #include <util/fs_helpers.h>
 #include <util/strencodings.h>
@@ -23,9 +26,31 @@
 #include <leveldb/helpers/memenv/memenv.h>
 #include <leveldb/iterator.h>
 #include <leveldb/options.h>
+#include <leveldb/slice.h>
 #include <leveldb/status.h>
+#include <leveldb/write_batch.h>
 #include <memory>
 #include <optional>
+#include <utility>
+
+static auto CharCast(const std::byte* data) { return reinterpret_cast<const char*>(data); }
+
+bool DestroyDB(const std::string& path_str)
+{
+    return leveldb::DestroyDB(path_str, {}).ok();
+}
+
+/** Handle database error by throwing dbwrapper_error exception.
+ */
+static void HandleError(const leveldb::Status& status)
+{
+    if (status.ok())
+        return;
+    const std::string errmsg = "Fatal LevelDB error: " + status.ToString();
+    LogPrintf("%s\n", errmsg);
+    LogPrintf("You can use -debug=leveldb to get more complete diagnostic messages\n");
+    throw dbwrapper_error(errmsg);
+}
 
 class CBitcoinLevelDBLogger : public leveldb::Logger {
 public:
@@ -127,24 +152,91 @@ static leveldb::Options GetOptions(size_t nCacheSize)
     return options;
 }
 
+struct CDBBatch::WriteBatchImpl {
+    leveldb::WriteBatch batch;
+};
+
+CDBBatch::CDBBatch(const CDBWrapper& _parent) : parent(_parent),
+                                                m_impl_batch{std::make_unique<CDBBatch::WriteBatchImpl>()},
+                                                ssValue(SER_DISK, CLIENT_VERSION){};
+
+CDBBatch::~CDBBatch() = default;
+
+void CDBBatch::Clear()
+{
+    m_impl_batch->batch.Clear();
+    size_estimate = 0;
+}
+
+void CDBBatch::WriteImpl(Span<const std::byte> key, CDataStream& ssValue)
+{
+    leveldb::Slice slKey(CharCast(key.data()), key.size());
+    ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
+    leveldb::Slice slValue(CharCast(ssValue.data()), ssValue.size());
+    m_impl_batch->batch.Put(slKey, slValue);
+    // LevelDB serializes writes as:
+    // - byte: header
+    // - varint: key length (1 byte up to 127B, 2 bytes up to 16383B, ...)
+    // - byte[]: key
+    // - varint: value length
+    // - byte[]: value
+    // The formula below assumes the key and value are both less than 16k.
+    size_estimate += 3 + (slKey.size() > 127) + slKey.size() + (slValue.size() > 127) + slValue.size();
+}
+
+void CDBBatch::EraseImpl(Span<const std::byte> key)
+{
+    leveldb::Slice slKey(CharCast(key.data()), key.size());
+    m_impl_batch->batch.Delete(slKey);
+    // LevelDB serializes erases as:
+    // - byte: header
+    // - varint: key length
+    // - byte[]: key
+    // The formula below assumes the key is less than 16kB.
+    size_estimate += 2 + (slKey.size() > 127) + slKey.size();
+}
+
+struct LevelDBContext {
+    //! custom environment this database is using (may be nullptr in case of default environment)
+    leveldb::Env* penv;
+
+    //! database options used
+    leveldb::Options options;
+
+    //! options used when reading from the database
+    leveldb::ReadOptions readoptions;
+
+    //! options used when iterating over values of the database
+    leveldb::ReadOptions iteroptions;
+
+    //! options used when writing to the database
+    leveldb::WriteOptions writeoptions;
+
+    //! options used when sync writing to the database
+    leveldb::WriteOptions syncoptions;
+
+    //! the database itself
+    leveldb::DB* pdb;
+};
+
 CDBWrapper::CDBWrapper(const DBParams& params)
-    : m_name{fs::PathToString(params.path.stem())}, m_path{params.path}, m_is_memory{params.memory_only}
+    : m_db_context{std::make_unique<LevelDBContext>()}, m_name{fs::PathToString(params.path.stem())}, m_path{params.path}, m_is_memory{params.memory_only}
 {
-    penv = nullptr;
-    readoptions.verify_checksums = true;
-    iteroptions.verify_checksums = true;
-    iteroptions.fill_cache = false;
-    syncoptions.sync = true;
-    options = GetOptions(params.cache_bytes);
-    options.create_if_missing = true;
+    DBContext().penv = nullptr;
+    DBContext().readoptions.verify_checksums = true;
+    DBContext().iteroptions.verify_checksums = true;
+    DBContext().iteroptions.fill_cache = false;
+    DBContext().syncoptions.sync = true;
+    DBContext().options = GetOptions(params.cache_bytes);
+    DBContext().options.create_if_missing = true;
     if (params.memory_only) {
-        penv = leveldb::NewMemEnv(leveldb::Env::Default());
-        options.env = penv;
+        DBContext().penv = leveldb::NewMemEnv(leveldb::Env::Default());
+        DBContext().options.env = DBContext().penv;
     } else {
         if (params.wipe_data) {
             LogPrintf("Wiping LevelDB in %s\n", fs::PathToString(params.path));
-            leveldb::Status result = leveldb::DestroyDB(fs::PathToString(params.path), options);
-            dbwrapper_private::HandleError(result);
+            leveldb::Status result = leveldb::DestroyDB(fs::PathToString(params.path), DBContext().options);
+            HandleError(result);
         }
         TryCreateDirectories(params.path);
         LogPrintf("Opening LevelDB in %s\n", fs::PathToString(params.path));
@@ -153,13 +245,13 @@ CDBWrapper::CDBWrapper(const DBParams& params)
     // because on POSIX leveldb passes the byte string directly to ::open(), and
     // on Windows it converts from UTF-8 to UTF-16 before calling ::CreateFileW
     // (see env_posix.cc and env_windows.cc).
-    leveldb::Status status = leveldb::DB::Open(options, fs::PathToString(params.path), &pdb);
-    dbwrapper_private::HandleError(status);
+    leveldb::Status status = leveldb::DB::Open(DBContext().options, fs::PathToString(params.path), &DBContext().pdb);
+    HandleError(status);
     LogPrintf("Opened LevelDB successfully\n");
 
     if (params.options.force_compact) {
         LogPrintf("Starting database compaction of %s\n", fs::PathToString(params.path));
-        pdb->CompactRange(nullptr, nullptr);
+        DBContext().pdb->CompactRange(nullptr, nullptr);
         LogPrintf("Finished database compaction of %s\n", fs::PathToString(params.path));
     }
 
@@ -185,16 +277,16 @@ CDBWrapper::CDBWrapper(const DBParams& params)
 
 CDBWrapper::~CDBWrapper()
 {
-    delete pdb;
-    pdb = nullptr;
-    delete options.filter_policy;
-    options.filter_policy = nullptr;
-    delete options.info_log;
-    options.info_log = nullptr;
-    delete options.block_cache;
-    options.block_cache = nullptr;
-    delete penv;
-    options.env = nullptr;
+    delete DBContext().pdb;
+    DBContext().pdb = nullptr;
+    delete DBContext().options.filter_policy;
+    DBContext().options.filter_policy = nullptr;
+    delete DBContext().options.info_log;
+    DBContext().options.info_log = nullptr;
+    delete DBContext().options.block_cache;
+    DBContext().options.block_cache = nullptr;
+    delete DBContext().penv;
+    DBContext().options.env = nullptr;
 }
 
 bool CDBWrapper::WriteBatch(CDBBatch& batch, bool fSync)
@@ -204,8 +296,8 @@ bool CDBWrapper::WriteBatch(CDBBatch& batch, bool fSync)
     if (log_memory) {
         mem_before = DynamicMemoryUsage() / 1024.0 / 1024;
     }
-    leveldb::Status status = pdb->Write(fSync ? syncoptions : writeoptions, &batch.batch);
-    dbwrapper_private::HandleError(status);
+    leveldb::Status status = DBContext().pdb->Write(fSync ? DBContext().syncoptions : DBContext().writeoptions, &batch.m_impl_batch->batch);
+    HandleError(status);
     if (log_memory) {
         double mem_after = DynamicMemoryUsage() / 1024.0 / 1024;
         LogPrint(BCLog::LEVELDB, "WriteBatch memory usage: db=%s, before=%.1fMiB, after=%.1fMiB\n",
@@ -218,7 +310,7 @@ size_t CDBWrapper::DynamicMemoryUsage() const
 {
     std::string memory;
     std::optional<size_t> parsed;
-    if (!pdb->GetProperty("leveldb.approximate-memory-usage", &memory) || !(parsed = ToIntegral<size_t>(memory))) {
+    if (!DBContext().pdb->GetProperty("leveldb.approximate-memory-usage", &memory) || !(parsed = ToIntegral<size_t>(memory))) {
         LogPrint(BCLog::LEVELDB, "Failed to get approximate-memory-usage property\n");
         return 0;
     }
@@ -244,6 +336,45 @@ std::vector<unsigned char> CDBWrapper::CreateObfuscateKey() const
     return ret;
 }
 
+std::optional<std::string> CDBWrapper::ReadImpl(Span<const std::byte> key) const
+{
+    leveldb::Slice slKey(CharCast(key.data()), key.size());
+    std::string strValue;
+    leveldb::Status status = DBContext().pdb->Get(DBContext().readoptions, slKey, &strValue);
+    if (!status.ok()) {
+        if (status.IsNotFound())
+            return std::nullopt;
+        LogPrintf("LevelDB read failure: %s\n", status.ToString());
+        HandleError(status);
+    }
+    return strValue;
+}
+
+bool CDBWrapper::ExistsImpl(Span<const std::byte> key) const
+{
+    leveldb::Slice slKey(CharCast(key.data()), key.size());
+
+    std::string strValue;
+    leveldb::Status status = DBContext().pdb->Get(DBContext().readoptions, slKey, &strValue);
+    if (!status.ok()) {
+        if (status.IsNotFound())
+            return false;
+        LogPrintf("LevelDB read failure: %s\n", status.ToString());
+        HandleError(status);
+    }
+    return true;
+}
+
+size_t CDBWrapper::EstimateSizeImpl(Span<const std::byte> key1, Span<const std::byte> key2) const
+{
+    leveldb::Slice slKey1(CharCast(key1.data()), key1.size());
+    leveldb::Slice slKey2(CharCast(key2.data()), key2.size());
+    uint64_t size = 0;
+    leveldb::Range range(slKey1, slKey2);
+    DBContext().pdb->GetApproximateSizes(&range, 1, &size);
+    return size;
+}
+
 bool CDBWrapper::IsEmpty()
 {
     std::unique_ptr<CDBIterator> it(NewIterator());
@@ -251,23 +382,43 @@ bool CDBWrapper::IsEmpty()
     return !(it->Valid());
 }
 
-CDBIterator::~CDBIterator() { delete piter; }
-bool CDBIterator::Valid() const { return piter->Valid(); }
-void CDBIterator::SeekToFirst() { piter->SeekToFirst(); }
-void CDBIterator::Next() { piter->Next(); }
+struct CDBIterator::IteratorImpl {
+    const std::unique_ptr<leveldb::Iterator> iter;
 
-namespace dbwrapper_private {
+    explicit IteratorImpl(leveldb::Iterator* _iter) : iter{_iter} {}
+};
 
-void HandleError(const leveldb::Status& status)
+CDBIterator::CDBIterator(const CDBWrapper& _parent, std::unique_ptr<IteratorImpl> _piter) : parent(_parent),
+                                                                                            m_impl_iter(std::move(_piter)) {}
+
+CDBIterator* CDBWrapper::NewIterator()
 {
-    if (status.ok())
-        return;
-    const std::string errmsg = "Fatal LevelDB error: " + status.ToString();
-    LogPrintf("%s\n", errmsg);
-    LogPrintf("You can use -debug=leveldb to get more complete diagnostic messages\n");
-    throw dbwrapper_error(errmsg);
+    return new CDBIterator{*this, std::make_unique<CDBIterator::IteratorImpl>(DBContext().pdb->NewIterator(DBContext().iteroptions))};
 }
 
+void CDBIterator::SeekImpl(Span<const std::byte> key)
+{
+    leveldb::Slice slKey(CharCast(key.data()), key.size());
+    m_impl_iter->iter->Seek(slKey);
+}
+
+Span<const std::byte> CDBIterator::GetKeyImpl() const
+{
+    return MakeByteSpan(m_impl_iter->iter->key());
+}
+
+Span<const std::byte> CDBIterator::GetValueImpl() const
+{
+    return MakeByteSpan(m_impl_iter->iter->value());
+}
+
+CDBIterator::~CDBIterator() = default;
+bool CDBIterator::Valid() const { return m_impl_iter->iter->Valid(); }
+void CDBIterator::SeekToFirst() { m_impl_iter->iter->SeekToFirst(); }
+void CDBIterator::Next() { m_impl_iter->iter->Next(); }
+
+namespace dbwrapper_private {
+
 const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w)
 {
     return w.obfuscate_key;
diff --git a/src/dbwrapper.h b/src/dbwrapper.h
index 4ae2106211..eac9594aa1 100644
--- a/src/dbwrapper.h
+++ b/src/dbwrapper.h
@@ -5,28 +5,21 @@
 #ifndef BITCOIN_DBWRAPPER_H
 #define BITCOIN_DBWRAPPER_H
 
+#include <attributes.h>
 #include <clientversion.h>
-#include <logging.h>
 #include <serialize.h>
 #include <span.h>
 #include <streams.h>
+#include <util/check.h>
 #include <util/fs.h>
 
 #include <cstddef>
-#include <cstdint>
 #include <exception>
-#include <leveldb/db.h>
-#include <leveldb/iterator.h>
-#include <leveldb/options.h>
-#include <leveldb/slice.h>
-#include <leveldb/status.h>
-#include <leveldb/write_batch.h>
+#include <memory>
+#include <optional>
 #include <stdexcept>
 #include <string>
 #include <vector>
-namespace leveldb {
-class Env;
-}
 
 static const size_t DBWRAPPER_PREALLOC_KEY_SIZE = 64;
 static const size_t DBWRAPPER_PREALLOC_VALUE_SIZE = 1024;
@@ -54,8 +47,6 @@ struct DBParams {
     DBOptions options{};
 };
 
-inline auto CharCast(const std::byte* data) { return reinterpret_cast<const char*>(data); }
-
 class dbwrapper_error : public std::runtime_error
 {
 public:
@@ -64,25 +55,19 @@ public:
 
 class CDBWrapper;
 
-namespace dbwrapper {
-    using leveldb::DestroyDB;
-}
-
 /** These should be considered an implementation detail of the specific database.
  */
 namespace dbwrapper_private {
 
-/** Handle database error by throwing dbwrapper_error exception.
- */
-void HandleError(const leveldb::Status& status);
-
 /** Work around circular dependency, as well as for testing in dbwrapper_tests.
  * Database obfuscation should be considered an implementation detail of the
  * specific database.
  */
 const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w);
 
-};
+}; // namespace dbwrapper_private
+
+bool DestroyDB(const std::string& path_str);
 
 /** Batch of changes queued to be written to a CDBWrapper */
 class CDBBatch
@@ -91,46 +76,34 @@ class CDBBatch
 
 private:
     const CDBWrapper &parent;
-    leveldb::WriteBatch batch;
+
+    struct WriteBatchImpl;
+    const std::unique_ptr<WriteBatchImpl> m_impl_batch;
 
     DataStream ssKey{};
     CDataStream ssValue;
 
     size_t size_estimate{0};
 
+    void WriteImpl(Span<const std::byte> key, CDataStream& ssValue);
+    void EraseImpl(Span<const std::byte> key);
+
 public:
     /**
      * @param[in] _parent   CDBWrapper that this batch is to be submitted to
      */
-    explicit CDBBatch(const CDBWrapper& _parent) : parent(_parent), ssValue(SER_DISK, CLIENT_VERSION){};
-
-    void Clear()
-    {
-        batch.Clear();
-        size_estimate = 0;
-    }
+    explicit CDBBatch(const CDBWrapper& _parent);
+    ~CDBBatch();
+    void Clear();
 
     template <typename K, typename V>
     void Write(const K& key, const V& value)
     {
         ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
-        ssKey << key;
-        leveldb::Slice slKey(CharCast(ssKey.data()), ssKey.size());
-
         ssValue.reserve(DBWRAPPER_PREALLOC_VALUE_SIZE);
+        ssKey << key;
         ssValue << value;
-        ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
-        leveldb::Slice slValue(CharCast(ssValue.data()), ssValue.size());
-
-        batch.Put(slKey, slValue);
-        // LevelDB serializes writes as:
-        // - byte: header
-        // - varint: key length (1 byte up to 127B, 2 bytes up to 16383B, ...)
-        // - byte[]: key
-        // - varint: value length
-        // - byte[]: value
-        // The formula below assumes the key and value are both less than 16k.
-        size_estimate += 3 + (slKey.size() > 127) + slKey.size() + (slValue.size() > 127) + slValue.size();
+        WriteImpl(ssKey, ssValue);
         ssKey.clear();
         ssValue.clear();
     }
@@ -140,15 +113,7 @@ public:
     {
         ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
-        leveldb::Slice slKey(CharCast(ssKey.data()), ssKey.size());
-
-        batch.Delete(slKey);
-        // LevelDB serializes erases as:
-        // - byte: header
-        // - varint: key length
-        // - byte[]: key
-        // The formula below assumes the key is less than 16kB.
-        size_estimate += 2 + (slKey.size() > 127) + slKey.size();
+        EraseImpl(ssKey);
         ssKey.clear();
     }
 
@@ -157,9 +122,16 @@ public:
 
 class CDBIterator
 {
+public:
+    struct IteratorImpl;
+
 private:
     const CDBWrapper &parent;
-    leveldb::Iterator *piter;
+    const std::unique_ptr<IteratorImpl> m_impl_iter;
+
+    void SeekImpl(Span<const std::byte> key);
+    Span<const std::byte> GetKeyImpl() const;
+    Span<const std::byte> GetValueImpl() const;
 
 public:
 
@@ -167,8 +139,7 @@ public:
      * @param[in] _parent          Parent CDBWrapper instance.
      * @param[in] _piter           The original leveldb iterator.
      */
-    CDBIterator(const CDBWrapper &_parent, leveldb::Iterator *_piter) :
-        parent(_parent), piter(_piter) { };
+    CDBIterator(const CDBWrapper& _parent, std::unique_ptr<IteratorImpl> _piter);
     ~CDBIterator();
 
     bool Valid() const;
@@ -179,16 +150,14 @@ public:
         DataStream ssKey{};
         ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
-        leveldb::Slice slKey(CharCast(ssKey.data()), ssKey.size());
-        piter->Seek(slKey);
+        SeekImpl(ssKey);
     }
 
     void Next();
 
     template<typename K> bool GetKey(K& key) {
-        leveldb::Slice slKey = piter->key();
         try {
-            DataStream ssKey{MakeByteSpan(slKey)};
+            DataStream ssKey{GetKeyImpl()};
             ssKey >> key;
         } catch (const std::exception&) {
             return false;
@@ -197,9 +166,8 @@ public:
     }
 
     template<typename V> bool GetValue(V& value) {
-        leveldb::Slice slValue = piter->value();
         try {
-            CDataStream ssValue{MakeByteSpan(slValue), SER_DISK, CLIENT_VERSION};
+            CDataStream ssValue{GetValueImpl(), SER_DISK, CLIENT_VERSION};
             ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
             ssValue >> value;
         } catch (const std::exception&) {
@@ -209,30 +177,14 @@ public:
     }
 };
 
+struct LevelDBContext;
+
 class CDBWrapper
 {
     friend const std::vector<unsigned char>& dbwrapper_private::GetObfuscateKey(const CDBWrapper &w);
 private:
-    //! custom environment this database is using (may be nullptr in case of default environment)
-    leveldb::Env* penv;
-
-    //! database options used
-    leveldb::Options options;
-
-    //! options used when reading from the database
-    leveldb::ReadOptions readoptions;
-
-    //! options used when iterating over values of the database
-    leveldb::ReadOptions iteroptions;
-
-    //! options used when writing to the database
-    leveldb::WriteOptions writeoptions;
-
-    //! options used when sync writing to the database
-    leveldb::WriteOptions syncoptions;
-
-    //! the database itself
-    leveldb::DB* pdb;
+    //! holds all leveldb-specific fields of this class
+    std::unique_ptr<LevelDBContext> m_db_context;
 
     //! the name of this database
     std::string m_name;
@@ -254,6 +206,11 @@ private:
     //! whether or not the database resides in memory
     bool m_is_memory;
 
+    std::optional<std::string> ReadImpl(Span<const std::byte> key) const;
+    bool ExistsImpl(Span<const std::byte> key) const;
+    size_t EstimateSizeImpl(Span<const std::byte> key1, Span<const std::byte> key2) const;
+    auto& DBContext() const LIFETIMEBOUND { return *Assert(m_db_context); }
+
 public:
     CDBWrapper(const DBParams& params);
     ~CDBWrapper();
@@ -267,18 +224,12 @@ public:
         DataStream ssKey{};
         ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
-        leveldb::Slice slKey(CharCast(ssKey.data()), ssKey.size());
-
-        std::string strValue;
-        leveldb::Status status = pdb->Get(readoptions, slKey, &strValue);
-        if (!status.ok()) {
-            if (status.IsNotFound())
-                return false;
-            LogPrintf("LevelDB read failure: %s\n", status.ToString());
-            dbwrapper_private::HandleError(status);
+        std::optional<std::string> strValue{ReadImpl(ssKey)};
+        if (!strValue) {
+            return false;
         }
         try {
-            CDataStream ssValue{MakeByteSpan(strValue), SER_DISK, CLIENT_VERSION};
+            CDataStream ssValue{MakeByteSpan(*strValue), SER_DISK, CLIENT_VERSION};
             ssValue.Xor(obfuscate_key);
             ssValue >> value;
         } catch (const std::exception&) {
@@ -309,17 +260,7 @@ public:
         DataStream ssKey{};
         ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
-        leveldb::Slice slKey(CharCast(ssKey.data()), ssKey.size());
-
-        std::string strValue;
-        leveldb::Status status = pdb->Get(readoptions, slKey, &strValue);
-        if (!status.ok()) {
-            if (status.IsNotFound())
-                return false;
-            LogPrintf("LevelDB read failure: %s\n", status.ToString());
-            dbwrapper_private::HandleError(status);
-        }
-        return true;
+        return ExistsImpl(ssKey);
     }
 
     template <typename K>
@@ -335,10 +276,7 @@ public:
     // Get an estimate of LevelDB memory usage (in bytes).
     size_t DynamicMemoryUsage() const;
 
-    CDBIterator *NewIterator()
-    {
-        return new CDBIterator(*this, pdb->NewIterator(iteroptions));
-    }
+    CDBIterator* NewIterator();
 
     /**
      * Return true if the database managed by this class contains no entries.
@@ -353,12 +291,7 @@ public:
         ssKey2.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey1 << key_begin;
         ssKey2 << key_end;
-        leveldb::Slice slKey1(CharCast(ssKey1.data()), ssKey1.size());
-        leveldb::Slice slKey2(CharCast(ssKey2.data()), ssKey2.size());
-        uint64_t size = 0;
-        leveldb::Range range(slKey1, slKey2);
-        pdb->GetApproximateSizes(&range, 1, &size);
-        return size;
+        return EstimateSizeImpl(ssKey1, ssKey2);
     }
 };
 
diff --git a/src/index/blockfilterindex.cpp b/src/index/blockfilterindex.cpp
index a860b3a94d..cc7d6687b8 100644
--- a/src/index/blockfilterindex.cpp
+++ b/src/index/blockfilterindex.cpp
@@ -8,6 +8,7 @@
 #include <dbwrapper.h>
 #include <hash.h>
 #include <index/blockfilterindex.h>
+#include <logging.h>
 #include <node/blockstorage.h>
 #include <util/fs_helpers.h>
 #include <validation.h>
diff --git a/src/init.cpp b/src/init.cpp
index 65f2d221bd..33389e695c 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -33,6 +33,7 @@
 #include <interfaces/chain.h>
 #include <interfaces/init.h>
 #include <interfaces/node.h>
+#include <logging.h>
 #include <mapport.h>
 #include <net.h>
 #include <net_permissions.h>
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 5bb9647f35..e2bbfe3308 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -17,6 +17,7 @@
 #include <headerssync.h>
 #include <index/blockfilterindex.h>
 #include <kernel/mempool_entry.h>
+#include <logging.h>
 #include <merkleblock.h>
 #include <netbase.h>
 #include <netmessagemaker.h>
diff --git a/src/node/interfaces.cpp b/src/node/interfaces.cpp
index 9c98e4cf0c..42e021fcc9 100644
--- a/src/node/interfaces.cpp
+++ b/src/node/interfaces.cpp
@@ -18,6 +18,7 @@
 #include <interfaces/wallet.h>
 #include <kernel/chain.h>
 #include <kernel/mempool_entry.h>
+#include <logging.h>
 #include <mapport.h>
 #include <net.h>
 #include <net_processing.h>
diff --git a/src/node/miner.cpp b/src/node/miner.cpp
index aa1a9a155c..caa2991819 100644
--- a/src/node/miner.cpp
+++ b/src/node/miner.cpp
@@ -15,6 +15,7 @@
 #include <consensus/tx_verify.h>
 #include <consensus/validation.h>
 #include <deploymentstatus.h>
+#include <logging.h>
 #include <policy/feerate.h>
 #include <policy/policy.h>
 #include <pow.h>
diff --git a/src/qt/bitcoin.cpp b/src/qt/bitcoin.cpp
index 8f45af9485..865871a6d4 100644
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@@ -9,7 +9,6 @@
 #include <qt/bitcoin.h>
 
 #include <chainparams.h>
-#include <node/context.h>
 #include <common/args.h>
 #include <common/init.h>
 #include <common/system.h>
@@ -17,6 +16,8 @@
 #include <interfaces/handler.h>
 #include <interfaces/init.h>
 #include <interfaces/node.h>
+#include <logging.h>
+#include <node/context.h>
 #include <node/interface_ui.h>
 #include <noui.h>
 #include <qt/bitcoingui.h>
diff --git a/src/qt/test/apptests.cpp b/src/qt/test/apptests.cpp
index fb8029cb65..b05009965f 100644
--- a/src/qt/test/apptests.cpp
+++ b/src/qt/test/apptests.cpp
@@ -6,6 +6,7 @@
 
 #include <chainparams.h>
 #include <key.h>
+#include <logging.h>
 #include <qt/bitcoin.h>
 #include <qt/bitcoingui.h>
 #include <qt/networkstyle.h>
diff --git a/src/qt/transactiondesc.cpp b/src/qt/transactiondesc.cpp
index fa110cfbc9..dae6a2dea9 100644
--- a/src/qt/transactiondesc.cpp
+++ b/src/qt/transactiondesc.cpp
@@ -18,6 +18,7 @@
 #include <interfaces/node.h>
 #include <interfaces/wallet.h>
 #include <key_io.h>
+#include <logging.h>
 #include <policy/policy.h>
 #include <validation.h>
 #include <wallet/types.h>
diff --git a/src/rpc/node.cpp b/src/rpc/node.cpp
index dc5ecb9cbc..6b3662996c 100644
--- a/src/rpc/node.cpp
+++ b/src/rpc/node.cpp
@@ -13,6 +13,7 @@
 #include <interfaces/init.h>
 #include <interfaces/ipc.h>
 #include <kernel/cs_main.h>
+#include <logging.h>
 #include <node/context.h>
 #include <rpc/server.h>
 #include <rpc/server_util.h>
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index 65c657da96..08ef890ec4 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -19,6 +19,7 @@
 #include <init/common.h>
 #include <interfaces/chain.h>
 #include <kernel/mempool_entry.h>
+#include <logging.h>
 #include <net.h>
 #include <net_processing.h>
 #include <node/blockstorage.h>
diff --git a/src/validation.cpp b/src/validation.cpp
index 396133a4cf..c45c847471 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -5056,7 +5056,7 @@ static bool DeleteCoinsDBFromDisk(const fs::path db_path, bool is_snapshot)
 
     // We have to destruct before this call leveldb::DB in order to release the db
     // lock, otherwise `DestroyDB` will fail. See `leveldb::~DBImpl()`.
-    const bool destroyed = dbwrapper::DestroyDB(path_str, {}).ok();
+    const bool destroyed = DestroyDB(path_str);
 
     if (!destroyed) {
         LogPrintf("error: leveldb DestroyDB call failed on %s\n", path_str);