Introducing a file-based database wlx.

sdk/wlxplugin.h

@@ -9,6 +9,7 @@
 #define lc_newparams	2
 #define lc_selectall	3
 #define lc_setpercent	4
+#define lc_focus	5
 
 #define lcp_wraptext	1
 #define lcp_fittowindow 2

wlx/dbview/.gitignore

@@ -0,0 +1 @@
+build/

wlx/dbview/CMakeLists.txt

@@ -0,0 +1,174 @@
+cmake_minimum_required(VERSION 3.20)
+project(dbview_qt6 CXX C)
+
+set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_AUTOMOC ON)
+
+# Allow older cmake_minimum_required in FetchContent dependencies
+set(CMAKE_POLICY_VERSION_MINIMUM 3.5 CACHE STRING "" FORCE)
+
+# Optional engine flags
+option(ENABLE_ROCKSDB_LEVELDB "Enable RocksDB and LevelDB support using RocksDB (large dependency)" OFF)
+if(ENABLE_ROCKSDB_LEVELDB)
+    add_compile_options(-include stdint.h)
+endif()
+
+find_package(Qt6 REQUIRED COMPONENTS Core Gui Widgets Sql)
+
+# Ensure the platform static library is built with -fPIC
+set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+
+# Pull in the platform library (builds libwlxbase_wlqt.a)
+add_subdirectory(
+    ${CMAKE_CURRENT_SOURCE_DIR}/../wlxbase_wlqt
+    ${CMAKE_CURRENT_BINARY_DIR}/wlxbase_wlqt
+)
+
+# ---------------------------------------------------------------------------
+# External dependencies via FetchContent
+# ---------------------------------------------------------------------------
+include(FetchContent)
+
+# --- DuckDB ---
+set(BUILD_SHELL OFF CACHE BOOL "" FORCE)
+set(BUILD_UNITTESTS OFF CACHE BOOL "" FORCE)
+set(BUILD_BENCHMARKS OFF CACHE BOOL "" FORCE)
+set(BUILD_EXTENSIONS "parquet" CACHE STRING "" FORCE)
+set(EXTENSION_STATIC_BUILD ON CACHE BOOL "" FORCE)
+set(ENABLE_EXTENSION_AUTOLOADING OFF CACHE BOOL "" FORCE)
+set(ENABLE_EXTENSION_AUTOINSTALL OFF CACHE BOOL "" FORCE)
+FetchContent_Declare(duckdb
+    GIT_REPOSITORY https://github.com/duckdb/duckdb.git
+    GIT_TAG        v1.3.0
+    GIT_SHALLOW    TRUE
+)
+FetchContent_MakeAvailable(duckdb)
+
+# --- RocksDB (optional) ---
+if(ENABLE_ROCKSDB_LEVELDB)
+    set(WITH_TESTS OFF CACHE BOOL "" FORCE)
+    set(WITH_BENCHMARK_TOOLS OFF CACHE BOOL "" FORCE)
+    set(WITH_TOOLS OFF CACHE BOOL "" FORCE)
+    set(WITH_GFLAGS OFF CACHE BOOL "" FORCE)
+    set(ROCKSDB_BUILD_SHARED OFF CACHE BOOL "" FORCE)
+    set(FAIL_ON_WARNINGS OFF CACHE BOOL "" FORCE)
+    FetchContent_Declare(rocksdb
+        GIT_REPOSITORY https://github.com/facebook/rocksdb.git
+        GIT_TAG        v9.11.2
+        GIT_SHALLOW    TRUE
+        PATCH_COMMAND  sed -i "1i #include <cstdint>" db/blob/blob_file_meta.h
+    )
+    FetchContent_MakeAvailable(rocksdb)
+endif()
+
+# --- MS Access static libmdb ---
+add_library(mdb STATIC
+    src/libmdb/catalog.c
+    src/libmdb/file.c
+    src/libmdb/table.c
+    src/libmdb/data.c
+    src/libmdb/dump.c
+    src/libmdb/backend.c
+    src/libmdb/money.c
+    src/libmdb/sargs.c
+    src/libmdb/index.c
+    src/libmdb/like.c
+    src/libmdb/write.c
+    src/libmdb/stats.c
+    src/libmdb/map.c
+    src/libmdb/props.c
+    src/libmdb/worktable.c
+    src/libmdb/options.c
+    src/libmdb/iconv.c
+    src/libmdb/version.c
+    src/libmdb/rc4.c
+    src/libmdb/fakeglib.c
+)
+target_include_directories(mdb PRIVATE
+    include/mdbtools
+)
+target_compile_definitions(mdb PRIVATE FAKE_GLIB=1 "TLS=__thread" HAVE_ICONV=1 "ICONV_CONST=")
+
+# ---------------------------------------------------------------------------
+# Plugin library
+# ---------------------------------------------------------------------------
+# NOTE: Headers must be listed explicitly so AUTOMOC processes them.
+# RocksDbEngine.h is excluded when ENABLE_ROCKSDB is OFF to prevent MOC
+# from generating code that references uncompiled RocksDbEngine symbols.
+set(DBVIEW_HEADERS
+    include/DbEngine.h
+    include/DbViewWidget.h
+    include/DuckDbEngine.h
+    include/DuckDbModel.h
+    include/KeyValueModel.h
+    include/SqliteEngine.h
+    include/FirebirdEngine.h
+    include/MdbEngine.h
+    include/BdbEngine.h
+    include/LmdbEngine.h
+)
+
+set(DBVIEW_SOURCES
+    ${DBVIEW_HEADERS}
+    src/wlx_entry.cpp
+    src/DbEngine.cpp
+    src/DbViewWidget.cpp
+    src/SqliteEngine.cpp
+    src/DuckDbEngine.cpp
+    src/DuckDbModel.cpp
+    src/KeyValueModel.cpp
+    src/FirebirdEngine.cpp
+    src/MdbEngine.cpp
+    src/BdbEngine.cpp
+    src/LmdbEngine.cpp
+)
+
+if(ENABLE_ROCKSDB_LEVELDB)
+    list(APPEND DBVIEW_SOURCES
+        include/LevelDbEngine.h src/LevelDbEngine.cpp
+        include/RocksDbEngine.h src/RocksDbEngine.cpp
+    )
+endif()
+
+add_library(dbview_qt6 SHARED ${DBVIEW_SOURCES})
+
+if(ENABLE_ROCKSDB_LEVELDB)
+    target_compile_definitions(dbview_qt6 PRIVATE ENABLE_ROCKSDB_LEVELDB)
+endif()
+
+set_target_properties(dbview_qt6 PROPERTIES
+    PREFIX ""
+    SUFFIX ".wlx"
+)
+
+target_include_directories(dbview_qt6 PRIVATE
+    include
+    include/mdbtools
+    ${CMAKE_CURRENT_SOURCE_DIR}/../../sdk
+    ${duckdb_SOURCE_DIR}/src/include
+)
+
+if(ENABLE_ROCKSDB_LEVELDB)
+    target_include_directories(dbview_qt6 PRIVATE
+        ${rocksdb_SOURCE_DIR}/include
+    )
+endif()
+
+set(DBVIEW_LINK_LIBS
+    wlxbase_wlqt
+    Qt6::Widgets
+    Qt6::Gui
+    Qt6::Core
+    Qt6::Sql
+    duckdb
+    mdb
+    lmdb
+    db
+)
+
+if(ENABLE_ROCKSDB_LEVELDB)
+    list(APPEND DBVIEW_LINK_LIBS rocksdb)
+endif()
+
+target_link_libraries(dbview_qt6 PRIVATE ${DBVIEW_LINK_LIBS})

wlx/dbview/README.md

@@ -0,0 +1,120 @@
+# dbview — Multi-Engine Database WLX Plugin
+
+![dbview screenshot](dbview.png)
+
+A Qt6 WLX (Lister) plugin for [Double Commander](https://doublecmd.github.io/) that views and edits database files: **SQLite**, **DuckDB**, **LevelDB**, **RocksDB**, **LMDB**, **Berkeley DB**, **Firebird Embedded**, **MS Access**, and **Apache Parquet**.
+
+Built on the [`wlxbase_wlqt`](../wlxbase_wlqt/) platform library.
+
+> [!WARNING]  
+> **DATA MUTATION & LOCKING WARNING**  
+> 
+> By default, this plugin attempts to open databases in **read-write** mode to allow direct grid editing and data mutation.
+> - **File Locking:** Opening a database with read-write privileges may lock the file, preventing other applications from writing to it.
+> - **Concurrent Access Fallback:** If the database file is locked by another process, the plugin will silently fall back to **read-only** mode.
+> - **Data Integrity:** Any edited cells must be explicitly committed using the **Commit** button (or `Ctrl+S` / `Ctrl+Shift+Z`) for relational databases, or are saved instantly for key-value stores. Handle write mode with care to prevent unintended database modifications.
+
+---
+
+## Features
+
+### All Engines
+- **Schema Navigation Tree:** Hierarchical tree panel on the left displaying Tables, Views, Columns (with data types, Primary/Foreign keys), and Indexes.
+- **Find** (`Ctrl+F`) — search across all visible cells in the selected table.
+- **Copy Selection** (`Ctrl+C`) — copy selected cell values as tab-separated values.
+- **Word Wrap & Grid Lines** — toolbar actions to toggle wrapping and gridlines.
+- **`GridMode::LiveDatabase`** — direct table mapping with minimal memory overhead.
+
+### SQL Engines (SQLite, DuckDB, Firebird Embedded, Apache Parquet)
+- **SQL Console:** A vertical split panel containing a query editor (with execution via `Ctrl+Return` or `Execute` button), results grid, and CSV/TSV results exporter.
+- **Apache Parquet Proxying:** Opening a `.parquet`/`.pq` file initializes an in-memory DuckDB database and reads it via a virtual `read_parquet` view, making it SQL-queryable.
+- **In-place Grid Editing:** Cells are editable, with modifications buffered.
+- **Commit / Revert** (`Ctrl+S` / `Ctrl+Z` or `Ctrl+Shift+Z`) — commit or rollback pending changes.
+
+### Key-Value & Non-Relational Engines (LevelDB, RocksDB, LMDB, Berkeley DB, MS Access)
+- **Hidden SQL Console:** The SQL Console panel is automatically hidden as these engines do not support custom SQL.
+- **Two-Column Grid:** Displays Key and Value columns.
+- **Immediate Writing:** Key-value writes are saved instantly (no buffering).
+- **Binary/BLOB Value Detection:** Non-UTF-8 values and large binaries display placeholder information `[Binary Data - X bytes]`.
+- **Right-Click Context Menu Options:**
+  - **Hex View Toggle:** Displays binary data as space-separated hex strings.
+  - **BLOB Export ("Save Cell to File"):** Save raw binary values to any local file.
+  - **BLOB Import ("Load File into Cell"):** Import binary files into a cell (available in write mode only).
+- **Directory Detection (LevelDB/RocksDB):** Selecting a `.sst`/`.ldb`/`.log` file inside a LevelDB/RocksDB directory automatically targets the parent database directory.
+
+---
+
+## Keyboard Shortcuts
+
+| Shortcut | Action |
+|----------|--------|
+| `Ctrl+S` | Commit changes (Relational engines only) |
+| `Ctrl+Z` | Revert pending changes (Relational engines only) |
+| `Ctrl+Shift+Z` | Alternative Commit/Redo shortcut |
+| `Ctrl+Return` | Execute custom SQL query inside the SQL Console |
+| `Ctrl+F` | Toggle Find panel |
+| `Ctrl+C` | Copy selection |
+
+---
+
+## Engine Selection Logic
+
+The factory (`DbEngine::createForFile()`) resolves the file type by extension and locks:
+
+| Extension / File Pattern | Engine | SQL Console | Read-Only | Notes |
+|-------------------------|--------|-------------|-----------|-------|
+| `.sqlite`, `.sqlite3`, `.db`, `.db3` | SQLite | Yes | No* | QSQLITE driver connection |
+| `.duckdb` | DuckDB | Yes | No* | C++ native client API |
+| `.parquet`, `.pq` | DuckDB | Yes | No* | Virtual view via `read_parquet()` |
+| `.fdb` | Firebird Embedded | Yes | No* | QIBASE SQL driver connection |
+| `.mdb`, `.accdb` (if user table) | MS Access | No | **Yes** | Statically linked `libmdb` |
+| `.lmdb`, `data.mdb` | LMDB | No | No* | C API client |
+| `.bdb` | Berkeley DB | No | No* | C API with B-Tree cursors |
+| `.ldb`, `.sst`, `.log` (if parent has `CURRENT`) | LevelDB | No | **Yes** | C++ API client via RocksDB (if compiled) |
+| `.sst`, `.log` (fallback if LevelDB fails) | RocksDB | No | **Yes** | C++ API (if compiled) |
+
+*\* Note: Opens as Read-Only automatically if the file lacks write permissions or if the database is currently locked by another process.*
+
+---
+
+## Building
+
+### Prerequisites
+- Qt6 (Core, Gui, Widgets, Sql)
+- CMake ≥ 3.20
+- Git (for FetchContent dependencies)
+- Libraries: `liblmdb`, `libdb` (Berkeley DB), `libfbclient` (Firebird client)
+
+### Compile
+```bash
+cd wlx/dbview
+mkdir build && cd build
+cmake ..
+make -j$(nproc)
+```
+
+To enable support for **LevelDB** and **RocksDB**, you must compile with the `ENABLE_ROCKSDB_LEVELDB` flag set to `ON`. This flag is disabled by default because linking the RocksDB libraries increases the final `dbview_qt6.wlx` plugin size by over 12 MB. Both formats will be opened in strict read-only mode.
+
+```bash
+cmake .. -DENABLE_ROCKSDB_LEVELDB=ON
+make -j$(nproc)
+```
+
+**Output:** `dbview_qt6.wlx` (shared library)
+
+---
+
+## Installation
+
+Add `dbview_qt6.wlx` to your Double Commander plugins list.
+
+**Default Detection String:**
+```
+EXT="DB" | EXT="SQLITE" | EXT="SQLITE3" | EXT="DB3" | EXT="DUCKDB" | EXT="LMDB" | EXT="BDB" | EXT="FDB" | EXT="MDB" | EXT="ACCDB" | EXT="PARQUET" | EXT="PQ"
+```
+
+**If compiled with `ENABLE_ROCKSDB_LEVELDB=ON`:**
+Include the extensions for LevelDB and RocksDB:
+```
+EXT="DB" | EXT="SQLITE" | EXT="SQLITE3" | EXT="DB3" | EXT="DUCKDB" | EXT="LDB" | EXT="SST" | EXT="LOG" | EXT="LMDB" | EXT="BDB" | EXT="FDB" | EXT="MDB" | EXT="ACCDB" | EXT="PARQUET" | EXT="PQ"
+```

wlx/dbview/include/BdbEngine.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include "DbEngine.h"
+#include <db.h>
+
+class BdbEngine : public DbEngine {
+    Q_OBJECT
+public:
+    explicit BdbEngine(QObject *parent = nullptr);
+    ~BdbEngine() override;
+
+    bool open(const QString &filepath) override;
+    void close() override;
+
+    QStringList tableNames() const override;
+    QAbstractItemModel *modelForTable(const QString &tableName) override;
+    QString currentTableName() const override;
+
+    bool supportsMultipleTables() const override { return false; }
+    bool supportsSubmitRevert() const override { return false; }
+    QString engineName() const override { return QStringLiteral("Berkeley DB"); }
+
+private:
+    int countKeys() const;
+
+    DB *m_db = nullptr;
+    int m_keyCount = 0;
+    QAbstractItemModel *m_model = nullptr;
+};