baseline: mongo-light working tree before concurrency refactor

src/main.zig

@@ -0,0 +1,58 @@
+const std = @import("std");
+const mongo = @import("mongo");
+
+const usage =
+    \\mongo-light — lightweight MongoDB-compatible document database
+    \\
+    \\usage: mongo-light [options]
+    \\  --port <n>    listen port (default 27017)
+    \\  --bind <ip>   bind address (default 127.0.0.1)
+    \\  --db <path>   database file (default mongo-light.log)
+    \\  --help        show this help
+    \\
+;
+
+pub fn main(init: std.process.Init) !void {
+    var port: u16 = 27017;
+    var bind_ip: []const u8 = "127.0.0.1";
+    var db_path: []const u8 = "mongo-light.log";
+
+    var it = std.process.Args.Iterator.init(init.minimal.args);
+    defer it.deinit();
+    _ = it.next(); // program name
+    while (it.next()) |arg| {
+        if (std.mem.eql(u8, arg, "--port")) {
+            const v = it.next() orelse return error.MissingValue;
+            port = std.fmt.parseInt(u16, v, 10) catch {
+                std.debug.print("mongo-light: invalid port '{s}'\n", .{v});
+                return error.InvalidPort;
+            };
+        } else if (std.mem.eql(u8, arg, "--bind")) {
+            bind_ip = it.next() orelse return error.MissingValue;
+        } else if (std.mem.eql(u8, arg, "--db")) {
+            db_path = it.next() orelse return error.MissingValue;
+        } else if (std.mem.eql(u8, arg, "--help") or std.mem.eql(u8, arg, "-h")) {
+            try std.Io.File.writeStreamingAll(.stdout(), init.io, usage);
+            return;
+        } else {
+            std.debug.print("mongo-light: unknown option '{s}'\n{s}", .{ arg, usage });
+            return error.UnknownOption;
+        }
+    }
+
+    const oid_gen = mongo.bson.ObjectIdGen.init(init.io);
+    var engine = try mongo.db.Engine.open(init.gpa, init.io, db_path);
+    defer engine.deinit();
+    std.debug.print("mongo-light: opened database '{s}'\n", .{db_path});
+
+    var server = mongo.server.Server{
+        .gpa = init.gpa,
+        .port = port,
+        .bind_ip = bind_ip,
+        .oid_gen = oid_gen,
+        .connection_counter = .init(1),
+        .engine = &engine,
+        .start_time = std.Io.Timestamp.now(init.io, .real),
+    };
+    try server.run();
+}