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