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//! Helpers for code generation that don't need macro expansion.
use crate::ir::context::BindgenContext;
use crate::ir::layout::Layout;
pub(crate) mod attributes {
use proc_macro2::{Ident, Span, TokenStream};
use std::{borrow::Cow, str::FromStr};
pub(crate) fn repr(which: &str) -> TokenStream {
let which = Ident::new(which, Span::call_site());
quote! {
#[repr( #which )]
}
}
pub(crate) fn repr_list(which_ones: &[&str]) -> TokenStream {
let which_ones = which_ones
.iter()
.cloned()
.map(|one| TokenStream::from_str(one).expect("repr to be valid"));
quote! {
#[repr( #( #which_ones ),* )]
}
}
pub(crate) fn derives(which_ones: &[&str]) -> TokenStream {
let which_ones = which_ones
.iter()
.cloned()
.map(|one| TokenStream::from_str(one).expect("derive to be valid"));
quote! {
#[derive( #( #which_ones ),* )]
}
}
pub(crate) fn inline() -> TokenStream {
quote! {
#[inline]
}
}
pub(crate) fn must_use() -> TokenStream {
quote! {
#[must_use]
}
}
pub(crate) fn non_exhaustive() -> TokenStream {
quote! {
#[non_exhaustive]
}
}
pub(crate) fn doc(comment: String) -> TokenStream {
if comment.is_empty() {
quote!()
} else {
quote!(#[doc = #comment])
}
}
pub(crate) fn link_name<const MANGLE: bool>(name: &str) -> TokenStream {
// LLVM mangles the name by default but it's already mangled.
// Prefixing the name with \u{1} should tell LLVM to not mangle it.
let name: Cow<'_, str> = if MANGLE {
name.into()
} else {
format!("\u{1}{}", name).into()
};
quote! {
#[link_name = #name]
}
}
}
/// Generates a proper type for a field or type with a given `Layout`, that is,
/// a type with the correct size and alignment restrictions.
pub(crate) fn blob(ctx: &BindgenContext, layout: Layout) -> syn::Type {
let opaque = layout.opaque();
// FIXME(emilio, #412): We fall back to byte alignment, but there are
// some things that legitimately are more than 8-byte aligned.
//
// Eventually we should be able to `unwrap` here, but...
let ty = match opaque.known_rust_type_for_array(ctx) {
Some(ty) => ty,
None => {
warn!("Found unknown alignment on code generation!");
syn::parse_quote! { u8 }
}
};
let data_len = opaque.array_size(ctx).unwrap_or(layout.size);
if data_len == 1 {
ty
} else {
syn::parse_quote! { [ #ty ; #data_len ] }
}
}
/// Integer type of the same size as the given `Layout`.
pub(crate) fn integer_type(
ctx: &BindgenContext,
layout: Layout,
) -> Option<syn::Type> {
Layout::known_type_for_size(ctx, layout.size)
}
/// Generates a bitfield allocation unit type for a type with the given `Layout`.
pub(crate) fn bitfield_unit(ctx: &BindgenContext, layout: Layout) -> syn::Type {
let size = layout.size;
let ty = syn::parse_quote! { __BindgenBitfieldUnit<[u8; #size]> };
if ctx.options().enable_cxx_namespaces {
return syn::parse_quote! { root::#ty };
}
ty
}
pub(crate) mod ast_ty {
use crate::ir::context::BindgenContext;
use crate::ir::function::FunctionSig;
use crate::ir::layout::Layout;
use crate::ir::ty::{FloatKind, IntKind};
use proc_macro2::{self, TokenStream};
use std::str::FromStr;
pub(crate) fn c_void(ctx: &BindgenContext) -> syn::Type {
// ctypes_prefix takes precedence
match ctx.options().ctypes_prefix {
Some(ref prefix) => {
let prefix = TokenStream::from_str(prefix.as_str()).unwrap();
syn::parse_quote! { #prefix::c_void }
}
None => {
if ctx.options().use_core &&
ctx.options().rust_features.core_ffi_c_void
{
syn::parse_quote! { ::core::ffi::c_void }
} else {
syn::parse_quote! { ::std::os::raw::c_void }
}
}
}
}
pub(crate) fn raw_type(ctx: &BindgenContext, name: &str) -> syn::Type {
let ident = ctx.rust_ident_raw(name);
match ctx.options().ctypes_prefix {
Some(ref prefix) => {
let prefix = TokenStream::from_str(prefix.as_str()).unwrap();
syn::parse_quote! { #prefix::#ident }
}
None => {
if ctx.options().use_core &&
ctx.options().rust_features().core_ffi_c
{
syn::parse_quote! { ::core::ffi::#ident }
} else {
syn::parse_quote! { ::std::os::raw::#ident }
}
}
}
}
pub(crate) fn int_kind_rust_type(
ctx: &BindgenContext,
ik: IntKind,
layout: Option<Layout>,
) -> syn::Type {
match ik {
IntKind::Bool => syn::parse_quote! { bool },
IntKind::Char { .. } => raw_type(ctx, "c_char"),
IntKind::SChar => raw_type(ctx, "c_schar"),
IntKind::UChar => raw_type(ctx, "c_uchar"),
IntKind::Short => raw_type(ctx, "c_short"),
IntKind::UShort => raw_type(ctx, "c_ushort"),
IntKind::Int => raw_type(ctx, "c_int"),
IntKind::UInt => raw_type(ctx, "c_uint"),
IntKind::Long => raw_type(ctx, "c_long"),
IntKind::ULong => raw_type(ctx, "c_ulong"),
IntKind::LongLong => raw_type(ctx, "c_longlong"),
IntKind::ULongLong => raw_type(ctx, "c_ulonglong"),
IntKind::WChar => {
let layout =
layout.expect("Couldn't compute wchar_t's layout?");
Layout::known_type_for_size(ctx, layout.size)
.expect("Non-representable wchar_t?")
}
IntKind::I8 => syn::parse_quote! { i8 },
IntKind::U8 => syn::parse_quote! { u8 },
IntKind::I16 => syn::parse_quote! { i16 },
IntKind::U16 => syn::parse_quote! { u16 },
IntKind::I32 => syn::parse_quote! { i32 },
IntKind::U32 => syn::parse_quote! { u32 },
IntKind::I64 => syn::parse_quote! { i64 },
IntKind::U64 => syn::parse_quote! { u64 },
IntKind::Custom { name, .. } => {
syn::parse_str(name).expect("Invalid integer type.")
}
IntKind::U128 => {
if ctx.options().rust_features.i128_and_u128 {
syn::parse_quote! { u128 }
} else {
// Best effort thing, but wrong alignment
// unfortunately.
syn::parse_quote! { [u64; 2] }
}
}
IntKind::I128 => {
if ctx.options().rust_features.i128_and_u128 {
syn::parse_quote! { i128 }
} else {
syn::parse_quote! { [u64; 2] }
}
}
}
}
pub(crate) fn float_kind_rust_type(
ctx: &BindgenContext,
fk: FloatKind,
layout: Option<Layout>,
) -> syn::Type {
// TODO: we probably should take the type layout into account more
// often?
//
// Also, maybe this one shouldn't be the default?
match (fk, ctx.options().convert_floats) {
(FloatKind::Float16, _) => {
// TODO: do f16 when rust lands it
ctx.generated_bindgen_float16();
if ctx.options().enable_cxx_namespaces {
syn::parse_quote! { root::__BindgenFloat16 }
} else {
syn::parse_quote! { __BindgenFloat16 }
}
}
(FloatKind::Float, true) => syn::parse_quote! { f32 },
(FloatKind::Double, true) => syn::parse_quote! { f64 },
(FloatKind::Float, false) => raw_type(ctx, "c_float"),
(FloatKind::Double, false) => raw_type(ctx, "c_double"),
(FloatKind::LongDouble, _) => {
match layout {
Some(layout) => {
match layout.size {
4 => syn::parse_quote! { f32 },
8 => syn::parse_quote! { f64 },
// TODO(emilio): If rust ever gains f128 we should
// use it here and below.
_ => super::integer_type(ctx, layout)
.unwrap_or(syn::parse_quote! { f64 }),
}
}
None => {
debug_assert!(
false,
"How didn't we know the layout for a primitive type?"
);
syn::parse_quote! { f64 }
}
}
}
(FloatKind::Float128, _) => {
if ctx.options().rust_features.i128_and_u128 {
syn::parse_quote! { u128 }
} else {
syn::parse_quote! { [u64; 2] }
}
}
}
}
pub(crate) fn int_expr(val: i64) -> TokenStream {
// Don't use quote! { #val } because that adds the type suffix.
let val = proc_macro2::Literal::i64_unsuffixed(val);
quote!(#val)
}
pub(crate) fn uint_expr(val: u64) -> TokenStream {
// Don't use quote! { #val } because that adds the type suffix.
let val = proc_macro2::Literal::u64_unsuffixed(val);
quote!(#val)
}
pub(crate) fn cstr_expr(mut string: String) -> TokenStream {
string.push('\0');
let b = proc_macro2::Literal::byte_string(string.as_bytes());
quote! {
#b
}
}
pub(crate) fn float_expr(
ctx: &BindgenContext,
f: f64,
) -> Result<TokenStream, ()> {
if f.is_finite() {
let val = proc_macro2::Literal::f64_unsuffixed(f);
return Ok(quote!(#val));
}
let prefix = ctx.trait_prefix();
if f.is_nan() {
return Ok(quote! {
::#prefix::f64::NAN
});
}
if f.is_infinite() {
return Ok(if f.is_sign_positive() {
quote! {
::#prefix::f64::INFINITY
}
} else {
quote! {
::#prefix::f64::NEG_INFINITY
}
});
}
warn!("Unknown non-finite float number: {:?}", f);
Err(())
}
pub(crate) fn arguments_from_signature(
signature: &FunctionSig,
ctx: &BindgenContext,
) -> Vec<TokenStream> {
let mut unnamed_arguments = 0;
signature
.argument_types()
.iter()
.map(|&(ref name, _ty)| match *name {
Some(ref name) => {
let name = ctx.rust_ident(name);
quote! { #name }
}
None => {
unnamed_arguments += 1;
let name =
ctx.rust_ident(format!("arg{}", unnamed_arguments));
quote! { #name }
}
})
.collect()
}
}