wayland_scanner/
server_gen.rs

1use proc_macro2::{Ident, Span, TokenStream};
2
3use quote::{format_ident, quote};
4
5use crate::{
6    protocol::{Interface, Protocol, Type},
7    util::{description_to_doc_attr, dotted_to_relname, is_keyword, snake_to_camel, to_doc_attr},
8    Side,
9};
10
11pub fn generate_server_objects(protocol: &Protocol) -> TokenStream {
12    protocol
13        .interfaces
14        .iter()
15        .filter(|iface| iface.name != "wl_display")
16        .map(generate_objects_for)
17        .collect()
18}
19
20fn generate_objects_for(interface: &Interface) -> TokenStream {
21    let mod_name = Ident::new(&interface.name, Span::call_site());
22    let mod_doc = interface.description.as_ref().map(description_to_doc_attr);
23    let iface_name = Ident::new(&snake_to_camel(&interface.name), Span::call_site());
24    let iface_const_name = format_ident!("{}_INTERFACE", interface.name.to_ascii_uppercase());
25
26    let enums = crate::common::generate_enums_for(interface);
27    let msg_constants = crate::common::gen_msg_constants(&interface.requests, &interface.events);
28
29    let requests = crate::common::gen_message_enum(
30        &format_ident!("Request"),
31        Side::Server,
32        true,
33        &interface.requests,
34    );
35    let events = crate::common::gen_message_enum(
36        &format_ident!("Event"),
37        Side::Server,
38        false,
39        &interface.events,
40    );
41
42    let parse_body = if interface.name == "wl_registry" {
43        quote! { unimplemented!("`wl_registry` is implemented internally in `wayland-server`") }
44    } else {
45        crate::common::gen_parse_body(interface, Side::Server)
46    };
47    let write_body = crate::common::gen_write_body(interface, Side::Server);
48    let methods = gen_methods(interface);
49
50    let event_ref = if interface.requests.is_empty() {
51        "This interface has no requests."
52    } else {
53        "See also the [Request] enum for this interface."
54    };
55    let docs = match &interface.description {
56        Some((short, long)) => format!("{short}\n\n{long}\n\n{event_ref}"),
57        None => format!("{}\n\n{}", interface.name, event_ref),
58    };
59    let doc_attr = to_doc_attr(&docs);
60
61    quote! {
62        #mod_doc
63        pub mod #mod_name {
64            use std::sync::Arc;
65            use std::os::unix::io::OwnedFd;
66
67            use super::wayland_server::{
68                backend::{
69                    smallvec, ObjectData, ObjectId, InvalidId, WeakHandle,
70                    protocol::{WEnum, Argument, Message, Interface, same_interface}
71                },
72                Resource, Dispatch, DisplayHandle, DispatchError, ResourceData, New, Weak,
73            };
74
75            #enums
76            #msg_constants
77            #requests
78            #events
79
80            #doc_attr
81            #[derive(Debug, Clone)]
82            pub struct #iface_name {
83                id: ObjectId,
84                version: u32,
85                data: Option<Arc<dyn std::any::Any + Send + Sync + 'static>>,
86                handle: WeakHandle,
87            }
88
89            impl std::cmp::PartialEq for #iface_name {
90                #[inline]
91                fn eq(&self, other: &#iface_name) -> bool {
92                    self.id == other.id
93                }
94            }
95
96            impl std::cmp::Eq for #iface_name {}
97
98            impl PartialEq<Weak<#iface_name>> for #iface_name {
99                #[inline]
100                fn eq(&self, other: &Weak<#iface_name>) -> bool {
101                    self.id == other.id()
102                }
103            }
104
105            impl std::borrow::Borrow<ObjectId> for #iface_name {
106                #[inline]
107                fn borrow(&self) -> &ObjectId {
108                    &self.id
109                }
110            }
111
112            impl std::hash::Hash for #iface_name {
113                #[inline]
114                fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
115                    self.id.hash(state)
116                }
117            }
118
119            impl super::wayland_server::Resource for #iface_name {
120                type Request = Request;
121                type Event<'event> = Event<'event>;
122
123                #[inline]
124                fn interface() -> &'static Interface{
125                    &super::#iface_const_name
126                }
127
128                #[inline]
129                fn id(&self) -> ObjectId {
130                    self.id.clone()
131                }
132
133                #[inline]
134                fn version(&self) -> u32 {
135                    self.version
136                }
137
138                #[inline]
139                fn data<U: 'static>(&self) -> Option<&U> {
140                    self.data.as_ref().and_then(|arc| (&**arc).downcast_ref::<ResourceData<Self, U>>()).map(|data| &data.udata)
141                }
142
143                #[inline]
144                fn object_data(&self) -> Option<&Arc<dyn std::any::Any + Send + Sync>> {
145                    self.data.as_ref()
146                }
147
148                fn handle(&self) -> &WeakHandle {
149                    &self.handle
150                }
151
152                #[inline]
153                fn from_id(conn: &DisplayHandle, id: ObjectId) -> Result<Self, InvalidId> {
154                    if !same_interface(id.interface(), Self::interface()) && !id.is_null(){
155                        return Err(InvalidId)
156                    }
157                    let version = conn.object_info(id.clone()).map(|info| info.version).unwrap_or(0);
158                    let data = conn.get_object_data(id.clone()).ok();
159                    Ok(#iface_name { id, data, version, handle: conn.backend_handle().downgrade() })
160                }
161
162                fn send_event(&self, evt: Self::Event<'_>) -> Result<(), InvalidId> {
163                    let handle = DisplayHandle::from(self.handle.upgrade().ok_or(InvalidId)?);
164                    handle.send_event(self, evt)
165                }
166
167                fn parse_request(conn: &DisplayHandle, msg: Message<ObjectId, OwnedFd>) -> Result<(Self, Self::Request), DispatchError> {
168                    #parse_body
169                }
170
171                fn write_event<'a>(&self, conn: &DisplayHandle, msg: Self::Event<'a>) -> Result<Message<ObjectId, std::os::unix::io::BorrowedFd<'a>>, InvalidId> {
172                    #write_body
173                }
174
175                fn __set_object_data(&mut self, odata: std::sync::Arc<dyn std::any::Any + Send + Sync + 'static>) {
176                    self.data = Some(odata);
177                }
178            }
179
180            impl #iface_name {
181                #methods
182            }
183        }
184    }
185}
186
187fn gen_methods(interface: &Interface) -> TokenStream {
188    interface
189        .events
190        .iter()
191        .map(|request| {
192            let method_name = format_ident!(
193                "{}{}",
194                if is_keyword(&request.name) { "_" } else { "" },
195                request.name
196            );
197            let enum_variant = Ident::new(&snake_to_camel(&request.name), Span::call_site());
198
199            let fn_args = request.args.iter().flat_map(|arg| {
200                let arg_name =
201                    format_ident!("{}{}", if is_keyword(&arg.name) { "_" } else { "" }, arg.name);
202
203                let arg_type = if let Some(ref enu) = arg.enum_ {
204                    let enum_type = dotted_to_relname(enu);
205                    quote! { #enum_type }
206                } else {
207                    match arg.typ {
208                        Type::Uint => quote! { u32 },
209                        Type::Int => quote! { i32 },
210                        Type::Fixed => quote! { f64 },
211                        Type::String => {
212                            if arg.allow_null {
213                                quote! { Option<String> }
214                            } else {
215                                quote! { String }
216                            }
217                        }
218                        Type::Array => {
219                            if arg.allow_null {
220                                quote! { Option<Vec<u8>> }
221                            } else {
222                                quote! { Vec<u8> }
223                            }
224                        }
225                        Type::Fd => quote! { ::std::os::unix::io::BorrowedFd<'_> },
226                        Type::Object | Type::NewId => {
227                            let iface = arg.interface.as_ref().unwrap();
228                            let iface_mod = Ident::new(iface, Span::call_site());
229                            let iface_type = Ident::new(&snake_to_camel(iface), Span::call_site());
230                            if arg.allow_null {
231                                quote! { Option<&super::#iface_mod::#iface_type> }
232                            } else {
233                                quote! { &super::#iface_mod::#iface_type }
234                            }
235                        }
236                        Type::Destructor => panic!("An argument cannot have type \"destructor\"."),
237                    }
238                };
239
240                Some(quote! {
241                    #arg_name: #arg_type
242                })
243            });
244
245            let enum_args = request.args.iter().flat_map(|arg| {
246                let arg_name =
247                    format_ident!("{}{}", if is_keyword(&arg.name) { "_" } else { "" }, arg.name);
248                if arg.enum_.is_some() {
249                    Some(quote! { #arg_name: WEnum::Value(#arg_name) })
250                } else if arg.typ == Type::Object || arg.typ == Type::NewId {
251                    if arg.allow_null {
252                        Some(quote! { #arg_name: #arg_name.cloned() })
253                    } else {
254                        Some(quote! { #arg_name: #arg_name.clone() })
255                    }
256                } else {
257                    Some(quote! { #arg_name })
258                }
259            });
260
261            let doc_attr = request.description.as_ref().map(description_to_doc_attr);
262
263            quote! {
264                #doc_attr
265                #[allow(clippy::too_many_arguments)]
266                pub fn #method_name(&self, #(#fn_args),*) {
267                    let _ = self.send_event(
268                        Event::#enum_variant {
269                            #(#enum_args),*
270                        }
271                    );
272                }
273            }
274        })
275        .collect()
276}
277
278#[cfg(test)]
279mod tests {
280    #[test]
281    fn server_gen() {
282        let protocol_file =
283            std::fs::File::open("./tests/scanner_assets/test-protocol.xml").unwrap();
284        let protocol_parsed = crate::parse::parse(protocol_file);
285        let generated: String = super::generate_server_objects(&protocol_parsed).to_string();
286        let generated = crate::format_rust_code(&generated);
287
288        let reference =
289            std::fs::read_to_string("./tests/scanner_assets/test-server-code.rs").unwrap();
290        let reference = crate::format_rust_code(&reference);
291
292        if reference != generated {
293            let diff = similar::TextDiff::from_lines(&reference, &generated);
294            print!("{}", diff.unified_diff().context_radius(10).header("reference", "generated"));
295            panic!("Generated does not match reference!")
296        }
297    }
298}