1//! Types and functions related to bindgen annotation comments.
2//!
3//! Users can add annotations in doc comments to types that they would like to
4//! replace other types with, mark as opaque, etc. This module deals with all of
5//! that stuff.
6
7use std::str::FromStr;
8
9use crate::clang;
10
11/// What kind of visibility modifier should be used for a struct or field?
12#[derive(Copy, PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Default)]
13pub enum FieldVisibilityKind {
14 /// Fields are marked as private, i.e., struct Foo {bar: bool}
15 Private,
16 /// Fields are marked as crate public, i.e., struct Foo {pub(crate) bar: bool}
17 PublicCrate,
18 /// Fields are marked as public, i.e., struct Foo {pub bar: bool}
19 #[default]
20 Public,
21}
22
23impl FromStr for FieldVisibilityKind {
24 type Err = String;
25
26 fn from_str(s: &str) -> Result<Self, Self::Err> {
27 match s {
28 "private" => Ok(Self::Private),
29 "crate" => Ok(Self::PublicCrate),
30 "public" => Ok(Self::Public),
31 _ => Err(format!("Invalid visibility kind: `{}`", s)),
32 }
33 }
34}
35
36impl std::fmt::Display for FieldVisibilityKind {
37 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
38 let s: &'static str = match self {
39 FieldVisibilityKind::Private => "private",
40 FieldVisibilityKind::PublicCrate => "crate",
41 FieldVisibilityKind::Public => "public",
42 };
43
44 s.fmt(f)
45 }
46}
47
48/// What kind of accessor should we provide for a field?
49#[derive(Copy, PartialEq, Eq, Clone, Debug)]
50pub(crate) enum FieldAccessorKind {
51 /// No accessor.
52 None,
53 /// Plain accessor.
54 Regular,
55 /// Unsafe accessor.
56 Unsafe,
57 /// Immutable accessor.
58 Immutable,
59}
60
61/// Annotations for a given item, or a field.
62///
63/// You can see the kind of comments that are accepted in the [Doxygen documentation](https://www.doxygen.nl/manual/docblocks.html).
64#[derive(Default, Clone, PartialEq, Eq, Debug)]
65pub(crate) struct Annotations {
66 /// Whether this item is marked as opaque. Only applies to types.
67 opaque: bool,
68 /// Whether this item should be hidden from the output. Only applies to
69 /// types, or enum variants.
70 hide: bool,
71 /// Whether this type should be replaced by another. The name is a
72 /// namespace-aware path.
73 use_instead_of: Option<Vec<String>>,
74 /// Manually disable deriving copy/clone on this type. Only applies to
75 /// struct or union types.
76 disallow_copy: bool,
77 /// Manually disable deriving debug on this type.
78 disallow_debug: bool,
79 /// Manually disable deriving/implement default on this type.
80 disallow_default: bool,
81 /// Whether to add a `#[must_use]` annotation to this type.
82 must_use_type: bool,
83 /// Visibility of struct fields. You can set this on
84 /// structs (it will apply to all the fields), or individual fields.
85 visibility_kind: Option<FieldVisibilityKind>,
86 /// The kind of accessor this field will have. Also can be applied to
87 /// structs so all the fields inside share it by default.
88 accessor_kind: Option<FieldAccessorKind>,
89 /// Whether this enum variant should be constified.
90 ///
91 /// This is controlled by the `constant` attribute, this way:
92 ///
93 /// ```cpp
94 /// enum Foo {
95 /// Bar = 0, /**< <div rustbindgen constant></div> */
96 /// Baz = 0,
97 /// };
98 /// ```
99 ///
100 /// In that case, bindgen will generate a constant for `Bar` instead of
101 /// `Baz`.
102 constify_enum_variant: bool,
103 /// List of explicit derives for this type.
104 derives: Vec<String>,
105}
106
107fn parse_accessor(s: &str) -> FieldAccessorKind {
108 match s {
109 "false" => FieldAccessorKind::None,
110 "unsafe" => FieldAccessorKind::Unsafe,
111 "immutable" => FieldAccessorKind::Immutable,
112 _ => FieldAccessorKind::Regular,
113 }
114}
115
116impl Annotations {
117 /// Construct new annotations for the given cursor and its bindgen comments
118 /// (if any).
119 pub(crate) fn new(cursor: &clang::Cursor) -> Option<Annotations> {
120 let mut anno = Annotations::default();
121 let mut matched_one = false;
122 anno.parse(&cursor.comment(), &mut matched_one);
123
124 if matched_one {
125 Some(anno)
126 } else {
127 None
128 }
129 }
130
131 /// Should this type be hidden?
132 pub(crate) fn hide(&self) -> bool {
133 self.hide
134 }
135
136 /// Should this type be opaque?
137 pub(crate) fn opaque(&self) -> bool {
138 self.opaque
139 }
140
141 /// For a given type, indicates the type it should replace.
142 ///
143 /// For example, in the following code:
144 ///
145 /// ```cpp
146 ///
147 /// /** <div rustbindgen replaces="Bar"></div> */
148 /// struct Foo { int x; };
149 ///
150 /// struct Bar { char foo; };
151 /// ```
152 ///
153 /// the generated code would look something like:
154 ///
155 /// ```
156 /// /** <div rustbindgen replaces="Bar"></div> */
157 /// struct Bar {
158 /// x: ::std::os::raw::c_int,
159 /// };
160 /// ```
161 ///
162 /// That is, code for `Foo` is used to generate `Bar`.
163 pub(crate) fn use_instead_of(&self) -> Option<&[String]> {
164 self.use_instead_of.as_deref()
165 }
166
167 /// The list of derives that have been specified in this annotation.
168 pub(crate) fn derives(&self) -> &[String] {
169 &self.derives
170 }
171
172 /// Should we avoid implementing the `Copy` trait?
173 pub(crate) fn disallow_copy(&self) -> bool {
174 self.disallow_copy
175 }
176
177 /// Should we avoid implementing the `Debug` trait?
178 pub(crate) fn disallow_debug(&self) -> bool {
179 self.disallow_debug
180 }
181
182 /// Should we avoid implementing the `Default` trait?
183 pub(crate) fn disallow_default(&self) -> bool {
184 self.disallow_default
185 }
186
187 /// Should this type get a `#[must_use]` annotation?
188 pub(crate) fn must_use_type(&self) -> bool {
189 self.must_use_type
190 }
191
192 /// What kind of accessors should we provide for this type's fields?
193 pub(crate) fn visibility_kind(&self) -> Option<FieldVisibilityKind> {
194 self.visibility_kind
195 }
196
197 /// What kind of accessors should we provide for this type's fields?
198 pub(crate) fn accessor_kind(&self) -> Option<FieldAccessorKind> {
199 self.accessor_kind
200 }
201
202 fn parse(&mut self, comment: &clang::Comment, matched: &mut bool) {
203 use clang_sys::CXComment_HTMLStartTag;
204 if comment.kind() == CXComment_HTMLStartTag &&
205 comment.get_tag_name() == "div" &&
206 comment
207 .get_tag_attrs()
208 .next()
209 .map_or(false, |attr| attr.name == "rustbindgen")
210 {
211 *matched = true;
212 for attr in comment.get_tag_attrs() {
213 match attr.name.as_str() {
214 "opaque" => self.opaque = true,
215 "hide" => self.hide = true,
216 "nocopy" => self.disallow_copy = true,
217 "nodebug" => self.disallow_debug = true,
218 "nodefault" => self.disallow_default = true,
219 "mustusetype" => self.must_use_type = true,
220 "replaces" => {
221 self.use_instead_of = Some(
222 attr.value.split("::").map(Into::into).collect(),
223 )
224 }
225 "derive" => self.derives.push(attr.value),
226 "private" => {
227 self.visibility_kind = if attr.value != "false" {
228 Some(FieldVisibilityKind::Private)
229 } else {
230 Some(FieldVisibilityKind::Public)
231 };
232 }
233 "accessor" => {
234 self.accessor_kind = Some(parse_accessor(&attr.value))
235 }
236 "constant" => self.constify_enum_variant = true,
237 _ => {}
238 }
239 }
240 }
241
242 for child in comment.get_children() {
243 self.parse(&child, matched);
244 }
245 }
246
247 /// Returns whether we've parsed a "constant" attribute.
248 pub(crate) fn constify_enum_variant(&self) -> bool {
249 self.constify_enum_variant
250 }
251}
252