Get client rendering a window with low-level code

examples/01_client_connect.zig

@@ -48,11 +48,8 @@ pub fn main() !void {
 
         if (header.object_id == registry_id) {
             const event = try wayland.deserialize(wayland.core.Registry.Event, header, message_buffer.items);
-            std.debug.print("{} {s} ", .{ header.object_id, @tagName(event) });
             switch (event) {
                 .global => |global| {
-                    std.debug.print("{} \"{}\" v{}\n", .{ global.name, std.zig.fmtEscapes(global.interface), global.version });
-
                     var buffer: [20]u32 = undefined;
                     if (std.mem.eql(u8, global.interface, "wl_shm")) {
                         const message = try wayland.serialize(
@@ -108,17 +105,306 @@ pub fn main() !void {
                         try socket.writeAll(std.mem.sliceAsBytes(message));
                     }
                 },
-                .global_remove => std.debug.print("{}\n", .{std.zig.fmtEscapes(std.mem.sliceAsBytes(message_buffer.items))}),
+                .global_remove => {},
             }
         } else if (header.object_id == registry_done_id) {
-            std.debug.print("<-", .{});
-            for (message_buffer.items) |word| {
-                std.debug.print(" {}", .{std.fmt.fmtSliceHexLower(std.mem.asBytes(&word))});
-            }
-            std.debug.print(" (sync event id)\n", .{});
             break;
         } else {
             std.debug.print("{} {x} \"{}\"\n", .{ header.object_id, header.size_and_opcode.opcode, std.zig.fmtEscapes(std.mem.sliceAsBytes(message_buffer.items)) });
         }
     }
+
+    const surface_id = 8;
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.core.Compositor.Request,
+            &buffer,
+            compositor_id,
+            .{ .create_surface = .{
+                .new_id = surface_id,
+            } },
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    const xdg_surface_id = 9;
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.xdg.WmBase.Request,
+            &buffer,
+            xdg_wm_base_id,
+            .{ .get_xdg_surface = .{
+                .id = xdg_surface_id,
+                .surface = surface_id,
+            } },
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    const xdg_toplevel_id = 10;
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.xdg.Surface.Request,
+            &buffer,
+            xdg_surface_id,
+            .{ .get_toplevel = .{
+                .id = xdg_toplevel_id,
+            } },
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.core.Surface.Request,
+            &buffer,
+            surface_id,
+            wayland.core.Surface.Request.commit,
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    {
+        var buffer: [5]u32 = undefined;
+        const message = try wayland.serialize(wayland.core.Display.Request, &buffer, 1, .{ .sync = .{ .callback = registry_done_id } });
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    var done = false;
+    var surface_configured = false;
+    while (!done or !surface_configured) {
+        var header: wayland.Header = undefined;
+        const header_bytes_read = try socket.readAll(std.mem.asBytes(&header));
+        if (header_bytes_read < @sizeOf(wayland.Header)) {
+            return error.SocketClosed;
+        }
+
+        try message_buffer.resize((header.size_and_opcode.size - @sizeOf(wayland.Header)) / @sizeOf(u32));
+        const bytes_read = try socket.readAll(std.mem.sliceAsBytes(message_buffer.items));
+        message_buffer.shrinkRetainingCapacity(bytes_read / @sizeOf(u32));
+
+        if (header.object_id == xdg_surface_id) {
+            const event = try wayland.deserialize(wayland.xdg.Surface.Event, header, message_buffer.items);
+            switch (event) {
+                .configure => |conf| {
+                    var buffer: [10]u32 = undefined;
+                    const message = try wayland.serialize(
+                        wayland.xdg.Surface.Request,
+                        &buffer,
+                        xdg_surface_id,
+                        .{ .ack_configure = .{
+                            .serial = conf.serial,
+                        } },
+                    );
+                    try socket.writeAll(std.mem.sliceAsBytes(message));
+                    surface_configured = true;
+                },
+            }
+        } else if (header.object_id == xdg_toplevel_id) {
+            // const event = try wayland.deserialize(wayland.xdg.Toplevel.Event, header, message_buffer.items);
+            // std.debug.print("<- {}\n", .{event});
+            std.debug.print("<- xdg_toplevel@{} {s} {}\n", .{ header.object_id, @tagName(@as(std.meta.Tag(wayland.xdg.Toplevel.Event), @enumFromInt(header.size_and_opcode.opcode))), std.zig.fmtEscapes(std.mem.sliceAsBytes(message_buffer.items)) });
+        } else if (header.object_id == registry_done_id) {
+            done = true;
+        } else if (header.object_id == 1) {
+            const event = try wayland.deserialize(wayland.core.Display.Event, header, message_buffer.items);
+            switch (event) {
+                .@"error" => |err| std.debug.print("<- error({}): {} {s}\n", .{ err.object_id, err.code, err.message }),
+                .delete_id => |id| std.debug.print("<- delete_id {}\n", .{id.name}),
+            }
+        } else {
+            std.debug.print("{} {x} \"{}\"\n", .{ header.object_id, header.size_and_opcode.opcode, std.zig.fmtEscapes(std.mem.sliceAsBytes(message_buffer.items)) });
+        }
+    }
+
+    // allocate a shared memory file for display purposes
+    const Pixel = [4]u8;
+    const framebuffer_size = [2]usize{ 128, 128 };
+    const framebuffer_file_len = framebuffer_size[0] * framebuffer_size[1] * @sizeOf(Pixel);
+
+    const framebuffer_fd = try std.os.memfd_create("my-wayland-framebuffer", 0);
+    try std.os.ftruncate(framebuffer_fd, framebuffer_file_len);
+    const framebuffer_bytes = try std.os.mmap(null, framebuffer_file_len, std.os.PROT.READ | std.os.PROT.WRITE, std.os.MAP.SHARED, framebuffer_fd, 0);
+    const framebuffer = @as([*][4]u8, @ptrCast(framebuffer_bytes.ptr))[0 .. framebuffer_bytes.len / @sizeOf([4]u8)];
+
+    // put some interesting colors into the framebuffer
+    for (framebuffer, 0..) |*pixel, i| {
+        pixel.* = .{
+            @truncate(i),
+            @truncate(i + 64),
+            @truncate(i + 128),
+            0xFF,
+        };
+    }
+
+    const wl_shm_pool_id = 11;
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.core.Shm.Request,
+            &buffer,
+            shm_id,
+            .{ .create_pool = .{
+                .new_id = wl_shm_pool_id,
+                .size = framebuffer_file_len,
+            } },
+        );
+        // Send the file descriptor through a control message
+        const message_bytes = std.mem.sliceAsBytes(message);
+        const msg_iov = [_]std.os.iovec_const{
+            .{
+                .iov_base = message_bytes.ptr,
+                .iov_len = message_bytes.len,
+            },
+        };
+        const control_message = cmsg(std.os.fd_t){
+            .level = std.os.SOL.SOCKET,
+            .type = 0x01, // value of SCM_RIGHTS
+            .data = framebuffer_fd,
+        };
+        const socket_message = std.os.msghdr_const{
+            .name = null,
+            .namelen = 0,
+            .iov = &msg_iov,
+            .iovlen = msg_iov.len,
+            // .control = null,
+            // .controllen = 0,
+            .control = &control_message,
+            .controllen = @sizeOf(cmsg(std.os.fd_t)),
+            .flags = 0,
+        };
+        _ = try std.os.sendmsg(socket.handle, &socket_message, 0);
+    }
+
+    const wl_buffer_id = 12;
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.core.ShmPool.Request,
+            &buffer,
+            wl_shm_pool_id,
+            .{ .create_buffer = .{
+                .new_id = wl_buffer_id,
+                .offset = 0,
+                .width = framebuffer_size[0],
+                .height = framebuffer_size[1],
+                .stride = framebuffer_size[0] * @sizeOf([4]u8),
+                .format = @intFromEnum(wayland.core.Shm.Format.argb8888),
+            } },
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.core.Surface.Request,
+            &buffer,
+            surface_id,
+            .{ .attach = .{
+                .buffer = wl_buffer_id,
+                .x = 0,
+                .y = 0,
+            } },
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.core.Surface.Request,
+            &buffer,
+            surface_id,
+            .{ .damage = .{
+                .x = 0,
+                .y = 0,
+                .width = std.math.maxInt(i32),
+                .height = std.math.maxInt(i32),
+            } },
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    {
+        var buffer: [10]u32 = undefined;
+        const message = try wayland.serialize(
+            wayland.core.Surface.Request,
+            &buffer,
+            surface_id,
+            wayland.core.Surface.Request.commit,
+        );
+        try socket.writeAll(std.mem.sliceAsBytes(message));
+    }
+
+    var running = true;
+    while (running) {
+        var header: wayland.Header = undefined;
+        const header_bytes_read = try socket.readAll(std.mem.asBytes(&header));
+        if (header_bytes_read < @sizeOf(wayland.Header)) {
+            return error.SocketClosed;
+        }
+
+        try message_buffer.resize((header.size_and_opcode.size - @sizeOf(wayland.Header)) / @sizeOf(u32));
+        const bytes_read = try socket.readAll(std.mem.sliceAsBytes(message_buffer.items));
+        message_buffer.shrinkRetainingCapacity(bytes_read / @sizeOf(u32));
+
+        if (header.object_id == xdg_surface_id) {
+            const event = try wayland.deserialize(wayland.xdg.Surface.Event, header, message_buffer.items);
+            switch (event) {
+                .configure => |conf| {
+                    var buffer: [10]u32 = undefined;
+                    const message = try wayland.serialize(
+                        wayland.xdg.Surface.Request,
+                        &buffer,
+                        xdg_surface_id,
+                        .{ .ack_configure = .{
+                            .serial = conf.serial,
+                        } },
+                    );
+                    try socket.writeAll(std.mem.sliceAsBytes(message));
+                },
+            }
+        } else if (header.object_id == xdg_toplevel_id) {
+            // const event = try wayland.deserialize(wayland.xdg.Toplevel.Event, header, message_buffer.items);
+            // std.debug.print("<- {}\n", .{event});
+            switch (@as(std.meta.Tag(wayland.xdg.Toplevel.Event), @enumFromInt(header.size_and_opcode.opcode))) {
+                .configure => {
+                    const width: i32 = @intCast(message_buffer.items[0]);
+                    const height: i32 = @intCast(message_buffer.items[1]);
+                    std.debug.print("<- xdg_toplevel@{} configure <{}, {}>\n", .{ header.object_id, width, height });
+                },
+                .close => running = false,
+                else => |tag| std.debug.print("<- xdg_toplevel@{} {s} {}\n", .{ header.object_id, @tagName(tag), std.zig.fmtEscapes(std.mem.sliceAsBytes(message_buffer.items)) }),
+            }
+        } else if (header.object_id == wl_buffer_id) {
+            const event = try wayland.deserialize(wayland.core.Buffer.Event, header, message_buffer.items);
+            std.debug.print("<- wl_buffer@{} {}\n", .{ header.object_id, event });
+        } else if (header.object_id == 1) {
+            const event = try wayland.deserialize(wayland.core.Display.Event, header, message_buffer.items);
+            switch (event) {
+                .@"error" => |err| std.debug.print("<- error({}): {} {s}\n", .{ err.object_id, err.code, err.message }),
+                .delete_id => {
+                    // TODO: add id to list of free ids
+                },
+            }
+        } else {
+            std.debug.print("{} {x} \"{}\"\n", .{ header.object_id, header.size_and_opcode.opcode, std.zig.fmtEscapes(std.mem.sliceAsBytes(message_buffer.items)) });
+        }
+    }
+}
+
+fn cmsg(comptime T: type) type {
+    const padding_size = (@sizeOf(T) + @sizeOf(c_long) - 1) & ~(@as(usize, @sizeOf(c_long)) - 1);
+    return extern struct {
+        len: c_ulong = @sizeOf(@This()) - padding_size,
+        level: c_int,
+        type: c_int,
+        data: T,
+        _padding: [padding_size]u8 align(1) = [_]u8{0} ** padding_size,
+    };
 }

src/core.zig

@@ -83,3 +83,142 @@ pub const Registry = struct {
         };
     };
 };
+
+pub const Compositor = struct {
+    pub const Request = union(Request.Tag) {
+        create_surface: CreateSurface,
+        create_region: CreateRegion,
+
+        pub const Tag = enum(u16) {
+            create_surface,
+            create_region,
+        };
+
+        pub const CreateSurface = struct {
+            new_id: u32,
+        };
+
+        pub const CreateRegion = struct {
+            new_id: u32,
+        };
+    };
+};
+
+pub const ShmPool = struct {
+    pub const Request = union(Request.Tag) {
+        create_buffer: struct {
+            new_id: u32,
+            offset: i32,
+            width: i32,
+            height: i32,
+            stride: i32,
+            // Shm.Format
+            format: u32,
+        },
+        destroy: void,
+        resize: struct {
+            size: i32,
+        },
+
+        pub const Tag = enum(u16) {
+            create_buffer,
+            destroy,
+            resize,
+        };
+    };
+};
+
+pub const Shm = struct {
+    pub const Request = union(Request.Tag) {
+        create_pool: CreatePool,
+
+        pub const Tag = enum(u16) {
+            create_pool,
+        };
+
+        pub const CreatePool = struct {
+            new_id: u32,
+            // file descriptors are sent through a control message
+            // fd: u32,
+            size: u32,
+        };
+    };
+
+    pub const Event = union(Event.Tag) {
+        format: Format,
+
+        pub const Tag = enum(u16) {
+            @"error",
+            delete_id,
+        };
+    };
+
+    pub const Format = enum(u32) {
+        argb8888,
+        xrgb8888,
+        _,
+    };
+};
+
+pub const Surface = struct {
+    pub const Request = union(Request.Tag) {
+        destroy: void,
+        attach: struct {
+            buffer: u32,
+            x: i32,
+            y: i32,
+        },
+        damage: struct {
+            x: i32,
+            y: i32,
+            width: i32,
+            height: i32,
+        },
+        frame: struct {
+            /// id of a new callback object
+            callback: u32,
+        },
+        set_opaque_region: struct {
+            region: u32,
+        },
+        set_input_region: struct {
+            region: u32,
+        },
+        commit: void,
+
+        pub const Tag = enum(u16) {
+            destroy,
+            attach,
+            damage,
+            frame,
+            set_opaque_region,
+            set_input_region,
+            commit,
+        };
+    };
+
+    pub const Event = union(Event.Tag) {
+        format: Format,
+
+        pub const Tag = enum(u16) {
+            @"error",
+            delete_id,
+        };
+
+        pub const Format = enum(u32) {
+            argb8888,
+            xrgb8888,
+            _,
+        };
+    };
+};
+
+pub const Buffer = struct {
+    pub const Request = union(enum) {
+        destroy: void,
+    };
+
+    pub const Event = union(enum) {
+        release: void,
+    };
+};

src/main.zig

@@ -1,6 +1,7 @@
 const std = @import("std");
 const testing = std.testing;
 pub const core = @import("./core.zig");
+pub const xdg = @import("./xdg.zig");
 
 pub fn getDisplayPath(gpa: std.mem.Allocator) ![]u8 {
     const xdg_runtime_dir_path = try std.process.getEnvVarOwned(gpa, "XDG_RUNTIME_DIR");
@@ -54,22 +55,55 @@ test "header from []u32" {
     );
 }
 
+pub fn readUInt(buffer: []const u32, parent_pos: *usize) !u32 {
+    var pos = parent_pos.*;
+    if (pos >= buffer.len) return error.EndOfStream;
+
+    const uint: u32 = @bitCast(buffer[pos]);
+    pos += 1;
+
+    parent_pos.* = pos;
+    return uint;
+}
+
+pub fn readInt(buffer: []const u32, parent_pos: *usize) !i32 {
+    var pos = parent_pos.*;
+    if (pos >= buffer.len) return error.EndOfStream;
+
+    const int: i32 = @bitCast(buffer[pos]);
+    pos += 1;
+
+    parent_pos.* = pos;
+    return int;
+}
+
+pub fn readString(buffer: []const u32, parent_pos: *usize) ![:0]const u8 {
+    var pos = parent_pos.*;
+
+    const len = try readUInt(buffer, &pos);
+    const wordlen = std.mem.alignForward(usize, len, @sizeOf(u32)) / @sizeOf(u32);
+
+    if (pos + wordlen > buffer.len) return error.EndOfStream;
+    const string = std.mem.sliceAsBytes(buffer[pos..])[0 .. len - 1 :0];
+    pos += std.mem.alignForward(usize, len, @sizeOf(u32)) / @sizeOf(u32);
+
+    parent_pos.* = pos;
+    return string;
+}
+
 pub fn deserializeArguments(comptime Signature: type, buffer: []const u32) !Signature {
+    if (Signature == void) return {};
     var result: Signature = undefined;
     var pos: usize = 0;
     inline for (std.meta.fields(Signature)) |field| {
         switch (@typeInfo(field.type)) {
-            .Int => {
-                @field(result, field.name) = @bitCast(buffer[pos]);
-                pos += 1;
+            .Int => |int_info| switch (int_info.signedness) {
+                .signed => @field(result, field.name) = try readInt(buffer, &pos),
+                .unsigned => @field(result, field.name) = try readUInt(buffer, &pos),
             },
             .Pointer => |ptr| switch (ptr.size) {
                 .Slice => {
-                    const len = buffer[pos];
-                    pos += 1;
-                    const byte_pos = pos * @sizeOf(u32);
-                    @field(result, field.name) = std.mem.sliceAsBytes(buffer)[byte_pos..][0 .. len - 1 :0];
-                    pos += std.mem.alignForward(usize, len, @sizeOf(u32)) / @sizeOf(u32);
+                    @field(result, field.name) = try readString(buffer, &pos);
                 },
                 else => @compileError("Unsupported type " ++ @typeName(field.type)),
             },
@@ -114,12 +148,13 @@ pub fn calculateSerializedWordLen(comptime Signature: type, message: Signature)
 
 /// Message must live until the iovec array is written.
 pub fn serializeArguments(comptime Signature: type, buffer: []u32, message: Signature) ![]u32 {
+    if (Signature == void) return buffer[0..0];
     var pos: usize = 0;
     inline for (std.meta.fields(Signature)) |field| {
         switch (@typeInfo(field.type)) {
             .Int => {
                 if (pos >= buffer.len) return error.OutOfMemory;
-                buffer[pos] = @field(message, field.name);
+                buffer[pos] = @bitCast(@field(message, field.name));
                 pos += 1;
             },
             .Pointer => |ptr| switch (ptr.size) {

src/xdg.zig

@@ -0,0 +1,168 @@
+pub const WmBase = struct {
+    pub const Request = union(Request.Tag) {
+        destroy: void,
+        create_positioner: struct {
+            id: u32,
+        },
+        get_xdg_surface: struct {
+            id: u32,
+            surface: u32,
+        },
+        pong: struct {
+            serial: u32,
+        },
+
+        pub const Tag = enum(u16) {
+            destroy,
+            create_positioner,
+            get_xdg_surface,
+            pong,
+        };
+    };
+
+    pub const Event = union(Event.Tag) {
+        ping: struct { serial: u32 },
+
+        pub const Tag = enum(u16) {
+            ping,
+        };
+    };
+
+    pub const Error = enum(u32) {
+        role,
+        defunct_surfaces,
+        not_the_topmost_popup,
+        invalid_popup_parent,
+        invalid_surface_state,
+        invalid_positioner,
+        unresponsive,
+    };
+};
+
+pub const Surface = struct {
+    pub const Request = union(enum) {
+        destroy: void,
+        get_toplevel: struct {
+            id: u32,
+        },
+        get_popup: struct {
+            id: u32,
+            /// Allows null
+            parent: u32,
+            positioner: u32,
+        },
+        set_window_geometry: struct {
+            x: i32,
+            y: i32,
+            width: i32,
+            height: i32,
+        },
+        ack_configure: struct {
+            serial: u32,
+        },
+    };
+
+    pub const Event = union(enum) {
+        configure: struct { serial: u32 },
+    };
+
+    pub const Error = enum(u32) {
+        not_constructed = 1,
+        already_constructed,
+        unconfigured_buffer,
+        invalid_serial,
+        invalid_size,
+        defunct_role_object,
+    };
+};
+
+pub const Toplevel = struct {
+    pub const Request = union(enum) {
+        destroy: void,
+        set_parent: struct {
+            /// Allows null
+            parent: u32,
+        },
+        set_title: struct {
+            title: []const u8,
+        },
+        set_app_id: struct {
+            app_id: []const u8,
+        },
+        show_window_menu: struct {
+            seat: u32,
+            serial: u32,
+            x: i32,
+            y: i32,
+        },
+        move: struct {
+            seat: u32,
+            serial: u32,
+        },
+        resize: struct {
+            seat: u32,
+            serial: u32,
+            edges: Toplevel.ResizeEdge,
+        },
+    };
+
+    pub const Event = union(enum) {
+        configure: struct {
+            width: i32,
+            height: i32,
+            states: []Toplevel.State,
+        },
+        close: void,
+        configure_bounds: struct {
+            width: i32,
+            height: i32,
+        },
+        wm_capabilities: struct {
+            capabilities: []Toplevel.WmCapabilities,
+        },
+    };
+
+    pub const ResizeEdge = enum(u32) {
+        none,
+        top,
+        bottom,
+        left,
+        top_left,
+        bottom_left,
+        right,
+        top_right,
+        bottom_right,
+        _,
+    };
+
+    pub const State = enum(u32) {
+        maximized,
+        fullscreen,
+        resizing,
+        activated,
+        tiled_left,
+        tiled_right,
+        tiled_top,
+        tiled_bottom,
+        suspended,
+        _,
+    };
+
+    pub const WmCapabilities = enum(u32) {
+        window_menu,
+        maximize,
+        fullscreen,
+        minimize,
+        _,
+    };
+
+    pub const Error = enum(u32) {
+        not_constructed = 1,
+        already_constructed,
+        unconfigured_buffer,
+        invalid_serial,
+        invalid_size,
+        defunct_role_object,
+        _,
+    };
+};