refactor: Move HandleError to dbwrapper implementation

Make it a static function in dbwrapper.cpp, since it is not used
elsewhere and when left in the header, would expose a leveldb type.

The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.

src/dbwrapper.cpp

@@ -38,6 +38,18 @@ 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:
     // This code is adapted from posix_logger.h, which is why it is using vsprintf.
@@ -199,7 +211,7 @@ CDBWrapper::CDBWrapper(const DBParams& params)
         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);
+            HandleError(result);
         }
         TryCreateDirectories(params.path);
         LogPrintf("Opening LevelDB in %s\n", fs::PathToString(params.path));
@@ -209,7 +221,7 @@ CDBWrapper::CDBWrapper(const DBParams& params)
     // 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);
+    HandleError(status);
     LogPrintf("Opened LevelDB successfully\n");
 
     if (params.options.force_compact) {
@@ -260,7 +272,7 @@ bool CDBWrapper::WriteBatch(CDBBatch& batch, bool fSync)
         mem_before = DynamicMemoryUsage() / 1024.0 / 1024;
     }
     leveldb::Status status = pdb->Write(fSync ? syncoptions : writeoptions, &batch.m_impl_batch->batch);
-    dbwrapper_private::HandleError(status);
+    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",
@@ -308,7 +320,7 @@ std::optional<std::string> CDBWrapper::ReadImpl(Span<const std::byte> ssKey) con
         if (status.IsNotFound())
             return std::nullopt;
         LogPrintf("LevelDB read failure: %s\n", status.ToString());
-        dbwrapper_private::HandleError(status);
+        HandleError(status);
     }
     return strValue;
 }
@@ -323,7 +335,7 @@ bool CDBWrapper::ExistsImpl(Span<const std::byte> ssKey) const
         if (status.IsNotFound())
             return false;
         LogPrintf("LevelDB read failure: %s\n", status.ToString());
-        dbwrapper_private::HandleError(status);
+        HandleError(status);
     }
     return true;
 }
@@ -371,16 +383,6 @@ void CDBIterator::Next() { m_impl_iter->iter->Next(); }
 
 namespace dbwrapper_private {
 
-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);
-}
-
 const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w)
 {
     return w.obfuscate_key;

src/dbwrapper.h

@@ -24,7 +24,6 @@
 #include <vector>
 namespace leveldb {
 class Env;
-class Status;
 }
 
 static const size_t DBWRAPPER_PREALLOC_KEY_SIZE = 64;
@@ -67,10 +66,6 @@ class CDBWrapper;
  */
 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.