initial

.gitignore

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+.zig-cache/
+zig-out/

README.md

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+# NeoNucleus
+
+The core of NeoComputers.
+
+It provides:
+- the computer model and state implementation
+- architecture system
+- (NOT NOW) basic component implementations
+- (NOT NOW) standard emulator
+- (NOT NOW) some extra components
+
+The library does not provide:
+- The sandbox (equivalent to OpenComputer's `machine.lua`)
+- Default architectures
+- Default host interop (as in, the vtables that control the basic component's internals, such as the filesystem implementation)
+
+The emulator *will* (as its gonna be made after the engine is functional) provide:
+- A simple Lua sandbox
+- Very simple workspaces
+- Ocelot components for debug
+- Headless mode (single computer, uses actual terminal for a teletypewriter).

build.zig

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+const std = @import("std");
+
+pub fn build(b: *std.Build) void {
+    const target = b.standardTargetOptions(.{});
+
+    const optimize = b.standardOptimizeOption(.{});
+
+    const engineStatic = b.addStaticLibrary(.{
+        .name = "neonucleus",
+        .root_source_file = b.path("src/engine.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    const install = b.getInstallStep();
+
+    b.installArtifact(engineStatic);
+    
+    const engineShared = b.addSharedLibrary(.{
+        .name = "neonucleus",
+        .root_source_file = b.path("src/engine.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    b.installArtifact(engineShared);
+
+    const engineStep = b.step("engine", "Builds the engine as a static library");
+    engineStep.dependOn(&engineStatic.step);
+    engineStep.dependOn(install);
+
+    const sharedStep = b.step("shared", "Builds the engine as a shared library");
+    sharedStep.dependOn(&engineShared.step);
+    sharedStep.dependOn(install);
+
+    const emulator = b.addExecutable(.{
+        .name = "neunucleus",
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    // forces us to link in everything too
+    emulator.linkLibrary(engineStatic);
+
+    b.installArtifact(emulator);
+    b.step("emulator", "Builds the emulator").dependOn(&emulator.step);
+
+    const run_cmd = b.addRunArtifact(emulator);
+
+    run_cmd.step.dependOn(install);
+
+    if (b.args) |args| {
+        run_cmd.addArgs(args);
+    }
+
+    const run_step = b.step("run", "Run the emulator");
+    run_step.dependOn(&run_cmd.step);
+
+    const lib_unit_tests = b.addTest(.{
+        .root_source_file = b.path("src/engine.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests);
+
+    const exe_unit_tests = b.addTest(.{
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);
+
+    const test_step = b.step("test", "Run unit tests");
+    test_step.dependOn(&run_lib_unit_tests.step);
+    test_step.dependOn(&run_exe_unit_tests.step);
+}

build.zig.zon

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+.{
+    // This is the default name used by packages depending on this one. For
+    // example, when a user runs `zig fetch --save <url>`, this field is used
+    // as the key in the `dependencies` table. Although the user can choose a
+    // different name, most users will stick with this provided value.
+    //
+    // It is redundant to include "zig" in this name because it is already
+    // within the Zig package namespace.
+    .name = "oc_reimagined",
+
+    // This is a [Semantic Version](https://semver.org/).
+    // In a future version of Zig it will be used for package deduplication.
+    .version = "0.0.0",
+
+    // This field is optional.
+    // This is currently advisory only; Zig does not yet do anything
+    // with this value.
+    //.minimum_zig_version = "0.11.0",
+
+    // This field is optional.
+    // Each dependency must either provide a `url` and `hash`, or a `path`.
+    // `zig build --fetch` can be used to fetch all dependencies of a package, recursively.
+    // Once all dependencies are fetched, `zig build` no longer requires
+    // internet connectivity.
+    .dependencies = .{
+        // See `zig fetch --save <url>` for a command-line interface for adding dependencies.
+        //.example = .{
+        //    // When updating this field to a new URL, be sure to delete the corresponding
+        //    // `hash`, otherwise you are communicating that you expect to find the old hash at
+        //    // the new URL.
+        //    .url = "https://example.com/foo.tar.gz",
+        //
+        //    // This is computed from the file contents of the directory of files that is
+        //    // obtained after fetching `url` and applying the inclusion rules given by
+        //    // `paths`.
+        //    //
+        //    // This field is the source of truth; packages do not come from a `url`; they
+        //    // come from a `hash`. `url` is just one of many possible mirrors for how to
+        //    // obtain a package matching this `hash`.
+        //    //
+        //    // Uses the [multihash](https://multiformats.io/multihash/) format.
+        //    .hash = "...",
+        //
+        //    // When this is provided, the package is found in a directory relative to the
+        //    // build root. In this case the package's hash is irrelevant and therefore not
+        //    // computed. This field and `url` are mutually exclusive.
+        //    .path = "foo",
+
+        //    // When this is set to `true`, a package is declared to be lazily
+        //    // fetched. This makes the dependency only get fetched if it is
+        //    // actually used.
+        //    .lazy = false,
+        //},
+    },
+
+    // Specifies the set of files and directories that are included in this package.
+    // Only files and directories listed here are included in the `hash` that
+    // is computed for this package. Only files listed here will remain on disk
+    // when using the zig package manager. As a rule of thumb, one should list
+    // files required for compilation plus any license(s).
+    // Paths are relative to the build root. Use the empty string (`""`) to refer to
+    // the build root itself.
+    // A directory listed here means that all files within, recursively, are included.
+    .paths = .{
+        "build.zig",
+        "build.zig.zon",
+        "src",
+        // For example...
+        //"LICENSE",
+        //"README.md",
+    },
+}

src/engine.zig

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+const std = @import("std");
+const testing = std.testing;
+
+pub const Computer = @import("engine/computer.zig");
+pub const Component = @import("engine/component.zig");
+pub const Universe = @import("engine/universe.zig");

src/engine/component.zig

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+address: []const u8,
+slot: isize,
+allocator: Allocator,
+userdata: *anyopaque,
+vtable: *const VTable,
+computer: *const Computer,
+
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const Component = @This();
+const Computer = @import("computer.zig");
+
+pub const Method = struct {
+    callback: Callback,
+    userdata: *anyopaque,
+    doc: []const u8,
+    direct: bool,
+
+    pub const Callback = *const fn(componentUser: *anyopaque, callbackUser: *anyopaque, computer: *const Computer) callconv(.C) c_int;
+};
+
+// not an extern struct because of how C API will work
+pub const VTable = struct {
+    componentType: []const u8,
+    methods: std.StringHashMap(Method),
+    resetBudget: ?*const fn(userdata: *anyopaque) callconv(.C) void,
+    passive: ?*const fn(userdata: *anyopaque) callconv(.C) void,
+    teardown: ?*const fn(userdata: *anyopaque) callconv(.C) void,
+
+    pub fn init(ctype: []const u8, allocator: Allocator) VTable {
+        return VTable {
+            .componentType = ctype,
+            .methods = std.StringHashMap(Method).init(allocator),
+            .resetBudget = null,
+            .teardown = null,
+        };
+    }
+};
+
+pub fn init(allocator: Allocator, address: []const u8, slot: isize, vtable: *const VTable, userdata: *anyopaque) !Component {
+    const ourAddr = try allocator.dupe(u8, address);
+    errdefer allocator.free(ourAddr);
+
+    return Component {
+        .address = ourAddr,
+        .slot = slot,
+        .allocator = allocator,
+        .userdata = userdata,
+        .vtable = vtable,
+    };
+}
+
+pub fn resetBudget(self: *const Component) void {
+    self.vtable.resetBudget(self.userdata);
+}
+
+pub fn passive(self: *const Component) void {
+    self.vtable.passive(self.userdata);
+}
+
+pub fn invoke(self: *const Component, method: []const u8) c_int {
+    const res = self.vtable.methods.get(method);
+    if(res) |f| {
+        return f.callback(self.userdata, f.userdata, self.computer);
+    }
+
+    // no such method
+    return 0;
+}
+
+pub fn deinit(self: Component) void {
+    self.vtable.teardown(self.userdata);
+    self.allocator.free(self.address);
+}

src/engine/computer.zig

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+address: []const u8,
+time: f64,
+allocator: Allocator,
+components: std.StringHashMap(Component),
+userdata: *anyopaque,
+universe: *Universe,
+stack: std.ArrayList(Value),
+userError: Error,
+isUserErrorAllocated: bool,
+architectureData: *anyopaque,
+architecture: Universe.Architecture,
+architectures: std.ArrayList(Universe.Architecture),
+state: State,
+
+pub fn init(address: []const u8, allocator: Allocator, userdata: *anyopaque, architecture: Universe.Architecture, universe: *Universe) Computer {
+    const ourAddr = try allocator.dupe(u8, address);
+    errdefer allocator.free(ourAddr);
+
+    var c = Computer {
+        .address = ourAddr,
+        .time = 0,
+        .allocator = allocator,
+        .components = std.StringHashMap(Component).init(allocator),
+        .userdata = userdata,
+        .universe = universe,
+        .args = std.ArrayList(Value).init(allocator),
+        .ret = std.ArrayList(Value).init(allocator),
+        .userError = Error {.none = 0},
+        .isUserErrorAllocated = false,
+        .architectureData = undefined,
+        .architecture = architecture,
+        .architectures = std.ArrayList(Universe.Architecture).init(allocator),
+        .state = State.running,
+    };
+    c.architectureData = architecture.setup(architecture.udata, &c);
+    return c;
+}
+
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const Computer = @This();
+const Component = @import("component.zig");
+const Universe = @import("universe.zig");
+
+pub const Error = union(enum) {
+    none,
+    raw: [*c]const u8,
+    allocated: [*c]const u8,
+};
+
+pub const State = enum {
+    running,
+    closing,
+    rebooting,
+    blackout,
+    overworked,
+};
+
+pub const Value = union(enum) {
+    nil,
+    integer: i64,
+    number: f64,
+    cstring: [*c]const u8,
+    string: []const u8,
+
+    pub fn toInteger(self: Value) i64 {
+        return switch(self) {
+            .integer => |i| i,
+            .number => |f| @intFromFloat(f),
+            else => 0,
+        };
+    }
+    
+    pub fn toNumber(self: Value) f64 {
+        return switch(self) {
+            .integer => |i| @floatFromInt(i),
+            .number => |f| f,
+            else => 0,
+        };
+    }
+
+    pub fn toString(self: Value) ?[]const u8 {
+        return switch(self) {
+            .string => |s| s,
+            .cstring => |c| std.mem.span(c),
+            else => null,
+        };
+    }
+    
+    pub fn toCString(self: Value) ?[*c]const u8 {
+        // normal strings are NOT CAST because it could be a safety violation
+        return switch(self) {
+            .cstring => |c| c,
+            else => null,
+        };
+    }
+
+    pub fn initNil() Value {
+        return Value {.nil = .{}};
+    }
+    
+    pub fn initInteger(i: i64) Value {
+        return Value {.integer = i};
+    }
+    
+    pub fn initNumber(f: f64) Value {
+        return Value {.number = f};
+    }
+    
+    pub fn initCString(cstr: [*c]const u8, allocator: Allocator) !Value {
+        const span = std.mem.span(cstr);
+        const mem = try allocator.dupeZ(u8, span);
+        return Value {.cstring = mem};
+    }
+    
+    pub fn initString(str: []const u8, allocator: Allocator) !Value {
+        const mem = try allocator.dupe(u8, str);
+        return Value {.string = mem};
+    }
+
+    pub fn deinit(self: Value, allocator: Allocator) void {
+        switch(self) {
+            .string => |s| allocator.free(s),
+            .cstring => |c| allocator.free(c),
+            else => {},
+        }
+    }
+};
+
+// Error handling
+
+pub fn clearError(self: *Computer) void {
+    switch(self.userError) {
+        .allocated => |c| {
+            self.allocator.free(c);
+        },
+        else => {},
+    }
+
+    self.userError = Error {.none = .{}};
+}
+
+pub fn setCError(self: *Computer, err: [*c]const u8) void {
+    self.clearError();
+    self.userError = Error {.raw = err};
+}
+
+pub fn setError(self: *Computer, err: [*c]const u8) void {
+    self.clearError();
+    const maybeBuf = self.allocator.dupeZ(u8, std.mem.span(err));
+    if(maybeBuf) |buf| {
+        self.userError = Error {.allocated = buf};
+    } else |e| {
+        _ = e;
+        self.setCError("out of memory");
+    }
+}
+
+pub fn getError(self: *const Computer) ?[*c]const u8 {
+    return switch(self.userError) {
+        .none => null,
+        .raw => |c| c,
+        .allocated => |c| c,
+    };
+}
+
+// Component functions
+
+pub fn invoke(self: *Computer, address: []const u8, method: []const u8) void {
+    self.setError(null);
+    if(self.components.get(address)) |c| {
+        c.invoke(method);
+        return;
+    }
+    self.setError("no such component");
+}
+
+// end of epilogue, just deletes everything
+pub fn resetCall(self: *Computer) void {
+    for(self.stack.items) |element| {
+        element.deinit(self.allocator);
+    }
+
+    // retain capacity for speed
+    self.stack.clearRetainingCapacity();
+}
+
+pub fn deinit(self: Computer) void {
+    // just to be safe
+    defer self.components.deinit();
+    defer self.stack.deinit();
+    defer self.architectures.deinit();
+
+    // absolutely destroy everything
+    // burn it all to the ground
+    // leave no evidence behind
+    self.resetCall();
+
+    self.architecture.demolish(self.architecture.udata, self.architectureData);
+
+    self.clearError();
+
+    var compIter = self.components.iterator();
+    while(compIter.next()) |entry| {
+        entry.value_ptr.deinit();
+    }
+}
+
+pub fn process(self: *Computer) void {
+    self.clearError();
+    self.architecture.tick(self.architecture.udata, self.architectureData, self);
+}

src/engine/universe.zig

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+allocator: Allocator,
+components: std.StringHashMap(Computer),
+host: Host,
+
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const Computer = @import("computer.zig");
+
+pub const Architecture = struct {
+    name: [*c]const u8,
+    udata: *anyopaque,
+    setup: *const fn(udata: *anyopaque, computer: *Computer) callconv(.C) *anyopaque,
+    tick: *const fn(udata: *anyopaque, context: *anyopaque, computer: *Computer) callconv(.C) void,
+    demolish: *const fn(udata: *anyopaque, context: *anyopaque) callconv(.C) void,
+};
+
+pub const Host = struct {
+};

src/main.zig

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+const std = @import("std");
+
+pub fn main() !void {
+    const stdout_file = std.io.getStdOut().writer();
+    var bw = std.io.bufferedWriter(stdout_file);
+    const stdout = bw.writer();
+
+    try stdout.print("Emulator is not even close to working.\n", .{});
+
+    try bw.flush(); // don't forget to flush!
+}