include all ROMs into final binary at comptime

build.zig

@@ -32,6 +32,24 @@ pub fn build(b: *std.Build) !void {
 
     const exe = b.addExecutable(.{ .name = "chip8-zig", .root_source_file = .{ .path = "src/main.zig" }, .optimize = optimize, .target = target });
 
+    // Provide filenames of all files in 'src/ROMs' to program as options
+    {
+        var files = std.ArrayList([]const u8).init(b.allocator);
+        defer files.deinit();
+        var options = b.addOptions();
+        var dir = try std.fs.cwd().openIterableDir("src/ROMs", .{ });
+        var it = dir.iterate();
+        while (try it.next()) |file| {
+            if (file.kind != .file) {
+                continue;
+            }
+            try files.append(b.pathJoin(&.{"ROMs", file.name}));
+        }
+
+        options.addOption([]const []const u8, "roms", files.items);
+        exe.addOptions("options", options);
+    }
+
     raylib.addTo(b, exe, target, optimize);
 
     // rl.link(b, exe, target, optimize);

src/main.zig

@@ -7,11 +7,17 @@ const ChipContext = @import("chip.zig");
 const RaylibChip = @import("raylib-chip.zig");
 const GlobalContext = @import("./global-context.zig");
 const MainScene = @import("./main-scene.zig");
+const options = @import("options");
 
 fn megabytes(amount: usize) usize {
     return amount * 1024 * 1024;
 }
 
+const ROM = struct {
+    name: []const u8,
+    data: []const u8,
+};
+
 pub fn main() anyerror!void {
     const memory = try std.heap.page_allocator.alloc(u8, megabytes(5));
     var fba = std.heap.FixedBufferAllocator.init(memory);
@@ -30,7 +36,19 @@ pub fn main() anyerror!void {
     var main_scene = try MainScene.init(allocator, &ctx);
     defer main_scene.deinit();
 
-    main_scene.chip.set_memory(0x200, @embedFile("ROMs/br8kout.ch8"));
+    comptime var roms = [1]ROM{ undefined } ** options.roms.len;
+    comptime {
+        var i = 0;
+        for (options.roms) |file| {
+            roms[i] = ROM{
+                .name = file,
+                .data = @embedFile(file)
+            };
+            i += 1;
+        }
+    }
+
+    main_scene.chip.set_memory(0x200, roms[3].data);
 
     const font_size = 24;
     const font_ttf_default_numchars = 95; // TTF font generation default charset: 95 glyphs (ASCII 32..126)