feat: add lmdb database in Storage

build.zig

@@ -13,6 +13,10 @@ const external_dependencies = [_]build_helpers.Dependency{
         .name = "httpz",
         .module_name = "httpz",
     },
+    .{
+        .name = "lmdb",
+        .module_name = "lmdb",
+    },
 };
 
 pub fn build(b: *std.Build) !void {

build.zig.zon

@@ -2,6 +2,10 @@
     .name = "btczee",
     .version = "0.0.1",
     .dependencies = .{
+        .lmdb = .{
+            .url = "https://github.com/canvasxyz/zig-lmdb/archive/refs/tags/v0.1.0.tar.gz",
+            .hash = "1220d5ca02660a791ea022d60a032ae56b629002d3930117d8047ecf615f012044f7",
+        },
         .zul = .{
             .url = "https://github.com/karlseguin/zul/archive/ae0c27350c0db6b460f22cba30b6b0c4a02d1ffd.zip",
             .hash = "1220457e2c8867f6734520d9b335f01e1d851d6fe7adaa7f6f0756158acaf6c5e87f",

src/block.zig

@@ -0,0 +1,6 @@
+const std = @import("std");
+
+pub const Block = struct {
+    hash: [32]u8,
+    height: i32,
+};

src/config/config.zig

@@ -18,7 +18,7 @@ pub const Config = struct {
     testnet: bool,
 
     /// Data directory
-    datadir: []const u8,
+    datadir: [:0]const u8,
 
     seednode: []const u8,
 
@@ -45,7 +45,7 @@ pub const Config = struct {
             .rpc_port = 8332,
             .p2p_port = 8333,
             .testnet = false,
-            .datadir = try allocator.dupe(u8, ".bitcoin"),
+            .datadir = ".bitcoin",
             .seednode = "",
         };
 
@@ -63,7 +63,7 @@ pub const Config = struct {
                 config.testnet = std.mem.eql(u8, value, "1");
             } else if (std.mem.eql(u8, key, "datadir")) {
                 allocator.free(config.datadir);
-                config.datadir = try allocator.dupe(u8, value);
+                config.datadir = try allocator.dupeZ(u8, value);
             }
         }
 

src/lib.zig

@@ -15,6 +15,7 @@ pub const rpc = @import("network/rpc.zig");
 pub const storage = @import("storage/storage.zig");
 pub const wallet = @import("wallet/wallet.zig");
 pub const miner = @import("miner/miner.zig");
+pub usingnamespace @import("block.zig");
 
 test {
     @import("std").testing.refAllDeclsRecursive(@This());

src/main.zig

@@ -154,7 +154,7 @@ fn runNodeCommand(program: *Program) !void {
     var mempool = try Mempool.init(program.allocator, &config);
     defer mempool.deinit();
 
-    var storage = try Storage.init(program.allocator, &config);
+    var storage = try Storage.init(&config);
     defer storage.deinit();
 
     var p2p = try P2P.init(program.allocator, &config);

src/storage/storage.zig

@@ -1,34 +1,55 @@
 const std = @import("std");
 const Config = @import("../config/config.zig").Config;
+const lmdb = @import("lmdb");
+const Block = @import("block").Block;
 
 /// Storage handler.
 ///
 /// The storage is responsible for handling the blockchain data.
 pub const Storage = struct {
-    allocator: std.mem.Allocator,
     config: *const Config,
+    env: lmdb.Environment,
 
     /// Initialize the storage
     ///
-    /// # Arguments
-    /// - `allocator`: Memory allocator
-    /// - `config`: Configuration
-    ///
-    /// # Returns
-    /// - `Storage`: Storage
-    pub fn init(allocator: std.mem.Allocator, config: *const Config) !Storage {
+    /// Will create the full path to the directory if it doesn't already exist.
+    pub fn init(config: *const Config) !Storage {
+        const datadir = config.datadir;
+        try std.fs.cwd().makePath(datadir);
+
+        // Init the db env
+        // `max_dbs` is set to 1:
+        // - "blocks"
+        const env = try lmdb.Environment.init(datadir, .{ .max_dbs = 1 });
+
         return Storage{
-            .allocator = allocator,
             .config = config,
+            .env = env,
         };
     }
 
     /// Deinitialize the storage
     ///
-    /// # Arguments
-    /// - `self`: Storage
-    pub fn deinit(self: *Storage) void {
-        // Clean up resources if needed
-        _ = self;
+    /// Release the lmdb environment handle.
+    pub fn deinit(self: Storage) void {
+        self.env.deinit();
+    }
+
+    pub fn init_transaction(self: Storage) !Transaction {
+        const txn = try lmdb.Transaction.init(self.env, .{ .mode = .ReadWrite });
+        return Transaction{ .txn = txn };
+    }
+};
+
+pub const Transaction = struct {
+    txn: lmdb.Transaction,
+
+    pub fn abort(self: Transaction) void {
+        self.txn.abort();
+    }
+
+    pub fn store_block(txn: Transaction, block: *Block) !void {
+        const blocks = try txn.database("blocks", .{ .create = true });
+        try blocks.set(block.hash, block);
     }
 };