Vendor things

third-party/vendor/bindgen/ir/enum_ty.rs

@@ -0,0 +1,320 @@
+//! Intermediate representation for C/C++ enumerations.
+
+use super::super::codegen::EnumVariation;
+use super::context::{BindgenContext, TypeId};
+use super::item::Item;
+use super::ty::{Type, TypeKind};
+use crate::clang;
+use crate::ir::annotations::Annotations;
+use crate::parse::{ClangItemParser, ParseError};
+use crate::regex_set::RegexSet;
+
+/// An enum representing custom handling that can be given to a variant.
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub enum EnumVariantCustomBehavior {
+    /// This variant will be a module containing constants.
+    ModuleConstify,
+    /// This variant will be constified, that is, forced to generate a constant.
+    Constify,
+    /// This variant will be hidden entirely from the resulting enum.
+    Hide,
+}
+
+/// A C/C++ enumeration.
+#[derive(Debug)]
+pub struct Enum {
+    /// The representation used for this enum; it should be an `IntKind` type or
+    /// an alias to one.
+    ///
+    /// It's `None` if the enum is a forward declaration and isn't defined
+    /// anywhere else, see `tests/headers/func_ptr_in_struct.h`.
+    repr: Option<TypeId>,
+
+    /// The different variants, with explicit values.
+    variants: Vec<EnumVariant>,
+}
+
+impl Enum {
+    /// Construct a new `Enum` with the given representation and variants.
+    pub fn new(repr: Option<TypeId>, variants: Vec<EnumVariant>) -> Self {
+        Enum { repr, variants }
+    }
+
+    /// Get this enumeration's representation.
+    pub fn repr(&self) -> Option<TypeId> {
+        self.repr
+    }
+
+    /// Get this enumeration's variants.
+    pub fn variants(&self) -> &[EnumVariant] {
+        &self.variants
+    }
+
+    /// Construct an enumeration from the given Clang type.
+    pub fn from_ty(
+        ty: &clang::Type,
+        ctx: &mut BindgenContext,
+    ) -> Result<Self, ParseError> {
+        use clang_sys::*;
+        debug!("Enum::from_ty {:?}", ty);
+
+        if ty.kind() != CXType_Enum {
+            return Err(ParseError::Continue);
+        }
+
+        let declaration = ty.declaration().canonical();
+        let repr = declaration
+            .enum_type()
+            .and_then(|et| Item::from_ty(&et, declaration, None, ctx).ok());
+        let mut variants = vec![];
+
+        let variant_ty =
+            repr.and_then(|r| ctx.resolve_type(r).safe_canonical_type(ctx));
+        let is_bool = variant_ty.map_or(false, Type::is_bool);
+
+        // Assume signedness since the default type by the C standard is an int.
+        let is_signed = variant_ty.map_or(true, |ty| match *ty.kind() {
+            TypeKind::Int(ref int_kind) => int_kind.is_signed(),
+            ref other => {
+                panic!("Since when enums can be non-integers? {:?}", other)
+            }
+        });
+
+        let type_name = ty.spelling();
+        let type_name = if type_name.is_empty() {
+            None
+        } else {
+            Some(type_name)
+        };
+        let type_name = type_name.as_deref();
+
+        let definition = declaration.definition().unwrap_or(declaration);
+        definition.visit(|cursor| {
+            if cursor.kind() == CXCursor_EnumConstantDecl {
+                let value = if is_bool {
+                    cursor.enum_val_boolean().map(EnumVariantValue::Boolean)
+                } else if is_signed {
+                    cursor.enum_val_signed().map(EnumVariantValue::Signed)
+                } else {
+                    cursor.enum_val_unsigned().map(EnumVariantValue::Unsigned)
+                };
+                if let Some(val) = value {
+                    let name = cursor.spelling();
+                    let annotations = Annotations::new(&cursor);
+                    let custom_behavior = ctx
+                        .options()
+                        .last_callback(|callbacks| {
+                            callbacks
+                                .enum_variant_behavior(type_name, &name, val)
+                        })
+                        .or_else(|| {
+                            let annotations = annotations.as_ref()?;
+                            if annotations.hide() {
+                                Some(EnumVariantCustomBehavior::Hide)
+                            } else if annotations.constify_enum_variant() {
+                                Some(EnumVariantCustomBehavior::Constify)
+                            } else {
+                                None
+                            }
+                        });
+
+                    let new_name = ctx
+                        .options()
+                        .last_callback(|callbacks| {
+                            callbacks.enum_variant_name(type_name, &name, val)
+                        })
+                        .or_else(|| {
+                            annotations
+                                .as_ref()?
+                                .use_instead_of()?
+                                .last()
+                                .cloned()
+                        })
+                        .unwrap_or_else(|| name.clone());
+
+                    let comment = cursor.raw_comment();
+                    variants.push(EnumVariant::new(
+                        new_name,
+                        name,
+                        comment,
+                        val,
+                        custom_behavior,
+                    ));
+                }
+            }
+            CXChildVisit_Continue
+        });
+        Ok(Enum::new(repr, variants))
+    }
+
+    fn is_matching_enum(
+        &self,
+        ctx: &BindgenContext,
+        enums: &RegexSet,
+        item: &Item,
+    ) -> bool {
+        let path = item.path_for_allowlisting(ctx);
+        let enum_ty = item.expect_type();
+
+        if enums.matches(path[1..].join("::")) {
+            return true;
+        }
+
+        // Test the variants if the enum is anonymous.
+        if enum_ty.name().is_some() {
+            return false;
+        }
+
+        self.variants().iter().any(|v| enums.matches(v.name()))
+    }
+
+    /// Returns the final representation of the enum.
+    pub fn computed_enum_variation(
+        &self,
+        ctx: &BindgenContext,
+        item: &Item,
+    ) -> EnumVariation {
+        // ModuleConsts has higher precedence before Rust in order to avoid
+        // problems with overlapping match patterns.
+        if self.is_matching_enum(
+            ctx,
+            &ctx.options().constified_enum_modules,
+            item,
+        ) {
+            EnumVariation::ModuleConsts
+        } else if self.is_matching_enum(
+            ctx,
+            &ctx.options().bitfield_enums,
+            item,
+        ) {
+            EnumVariation::NewType {
+                is_bitfield: true,
+                is_global: false,
+            }
+        } else if self.is_matching_enum(ctx, &ctx.options().newtype_enums, item)
+        {
+            EnumVariation::NewType {
+                is_bitfield: false,
+                is_global: false,
+            }
+        } else if self.is_matching_enum(
+            ctx,
+            &ctx.options().newtype_global_enums,
+            item,
+        ) {
+            EnumVariation::NewType {
+                is_bitfield: false,
+                is_global: true,
+            }
+        } else if self.is_matching_enum(
+            ctx,
+            &ctx.options().rustified_enums,
+            item,
+        ) {
+            EnumVariation::Rust {
+                non_exhaustive: false,
+            }
+        } else if self.is_matching_enum(
+            ctx,
+            &ctx.options().rustified_non_exhaustive_enums,
+            item,
+        ) {
+            EnumVariation::Rust {
+                non_exhaustive: true,
+            }
+        } else if self.is_matching_enum(
+            ctx,
+            &ctx.options().constified_enums,
+            item,
+        ) {
+            EnumVariation::Consts
+        } else {
+            ctx.options().default_enum_style
+        }
+    }
+}
+
+/// A single enum variant, to be contained only in an enum.
+#[derive(Debug)]
+pub struct EnumVariant {
+    /// The name of the variant.
+    name: String,
+
+    /// The original name of the variant (without user mangling)
+    name_for_allowlisting: String,
+
+    /// An optional doc comment.
+    comment: Option<String>,
+
+    /// The integer value of the variant.
+    val: EnumVariantValue,
+
+    /// The custom behavior this variant may have, if any.
+    custom_behavior: Option<EnumVariantCustomBehavior>,
+}
+
+/// A constant value assigned to an enumeration variant.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum EnumVariantValue {
+    /// A boolean constant.
+    Boolean(bool),
+
+    /// A signed constant.
+    Signed(i64),
+
+    /// An unsigned constant.
+    Unsigned(u64),
+}
+
+impl EnumVariant {
+    /// Construct a new enumeration variant from the given parts.
+    pub fn new(
+        name: String,
+        name_for_allowlisting: String,
+        comment: Option<String>,
+        val: EnumVariantValue,
+        custom_behavior: Option<EnumVariantCustomBehavior>,
+    ) -> Self {
+        EnumVariant {
+            name,
+            name_for_allowlisting,
+            comment,
+            val,
+            custom_behavior,
+        }
+    }
+
+    /// Get this variant's name.
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    /// Get this variant's name.
+    pub fn name_for_allowlisting(&self) -> &str {
+        &self.name_for_allowlisting
+    }
+
+    /// Get this variant's value.
+    pub fn val(&self) -> EnumVariantValue {
+        self.val
+    }
+
+    /// Get this variant's documentation.
+    pub fn comment(&self) -> Option<&str> {
+        self.comment.as_deref()
+    }
+
+    /// Returns whether this variant should be enforced to be a constant by code
+    /// generation.
+    pub fn force_constification(&self) -> bool {
+        self.custom_behavior
+            .map_or(false, |b| b == EnumVariantCustomBehavior::Constify)
+    }
+
+    /// Returns whether the current variant should be hidden completely from the
+    /// resulting rust enum.
+    pub fn hidden(&self) -> bool {
+        self.custom_behavior
+            .map_or(false, |b| b == EnumVariantCustomBehavior::Hide)
+    }
+}