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Switch to core::ffi::c_* for C types instead of libc::c_* #297

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5497faa
Use usize instead of libc::intptr_t internally when transmuting funct…
ahomescu Sep 15, 2020
fe573ea
Use std::os::raw C types instead of the libc ones by default, with tr…
ahomescu Sep 15, 2020
dde4840
s/r#usize/usize_ty/
ahomescu Sep 15, 2020
3471d91
Fix test_sections.rs test
ahomescu Sep 15, 2020
fe5d74f
Replace use-libc-types option with ctypes-prefix
ahomescu Sep 15, 2020
835fc31
Break a long line manually
ahomescu Sep 15, 2020
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65 changes: 44 additions & 21 deletions c2rust-transpile/src/convert_type.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,7 @@ pub struct TypeConverter {
suffix_names: HashMap<(CDeclId, &'static str), String>,
features: HashSet<&'static str>,
emit_no_std: bool,
ctypes_prefix: String,
}

pub const RESERVED_NAMES: [&str; 103] = [
Expand Down Expand Up @@ -133,14 +134,15 @@ pub const RESERVED_NAMES: [&str; 103] = [
];

impl TypeConverter {
pub fn new(emit_no_std: bool) -> TypeConverter {
pub fn new(emit_no_std: bool, ctypes_prefix: String) -> TypeConverter {
TypeConverter {
translate_valist: false,
renamer: Renamer::new(&RESERVED_NAMES),
fields: HashMap::new(),
suffix_names: HashMap::new(),
features: HashSet::new(),
emit_no_std,
ctypes_prefix,
}
}

Expand Down Expand Up @@ -275,7 +277,7 @@ impl TypeConverter {
CTypeKind::Void => {
Ok(mk()
.set_mutbl(mutbl)
.ptr_ty(mk().path_ty(vec!["libc", "c_void"])))
.ptr_ty(mk().path_ty(vec!["core", "ffi", "c_void"])))
}

CTypeKind::VariableArray(mut elt, _len) => {
Expand All @@ -301,6 +303,41 @@ impl TypeConverter {
}
}

/// Convert a primitive C type kind into the equivalent Rust type
pub fn convert_primitive_type_kind(&self, kind: &CTypeKind) -> Option<P<Ty>> {
let primitive_type = |ty: &str| {
let path = self
.ctypes_prefix
.split("::")
.chain(std::iter::once(ty))
.collect::<Vec<_>>();
mk().path_ty(mk().path(path))
};

match kind {
CTypeKind::Void => Some(mk().tuple_ty(vec![] as Vec<P<Ty>>)),
CTypeKind::Bool => Some(mk().path_ty(mk().path(vec!["bool"]))),
CTypeKind::Short => Some(primitive_type("c_short")),
CTypeKind::Int => Some(primitive_type("c_int")),
CTypeKind::Long => Some(primitive_type("c_long")),
CTypeKind::LongLong => Some(primitive_type("c_longlong")),
CTypeKind::UShort => Some(primitive_type("c_ushort")),
CTypeKind::UInt => Some(primitive_type("c_uint")),
CTypeKind::ULong => Some(primitive_type("c_ulong")),
CTypeKind::ULongLong => Some(primitive_type("c_ulonglong")),
CTypeKind::SChar => Some(primitive_type("c_schar")),
CTypeKind::UChar => Some(primitive_type("c_uchar")),
CTypeKind::Char => Some(primitive_type("c_char")),
CTypeKind::Float => Some(primitive_type("c_float")),
CTypeKind::Double => Some(primitive_type("c_double")),
CTypeKind::LongDouble => Some(mk().path_ty(mk().path(vec!["f128", "f128"]))),
CTypeKind::Int128 => Some(mk().path_ty(mk().path(vec!["i128"]))),
CTypeKind::UInt128 => Some(mk().path_ty(mk().path(vec!["u128"]))),

_ => None
}
}

/// Convert a `C` type to a `Rust` one. For the moment, these are expected to have compatible
/// memory layouts.
pub fn convert(
Expand All @@ -315,26 +352,12 @@ impl TypeConverter {
return Ok(ty);
}

match ctxt.index(ctype).kind {
CTypeKind::Void => Ok(mk().tuple_ty(vec![] as Vec<P<Ty>>)),
CTypeKind::Bool => Ok(mk().path_ty(mk().path(vec!["bool"]))),
CTypeKind::Short => Ok(mk().path_ty(mk().path(vec!["libc", "c_short"]))),
CTypeKind::Int => Ok(mk().path_ty(mk().path(vec!["libc", "c_int"]))),
CTypeKind::Long => Ok(mk().path_ty(mk().path(vec!["libc", "c_long"]))),
CTypeKind::LongLong => Ok(mk().path_ty(mk().path(vec!["libc", "c_longlong"]))),
CTypeKind::UShort => Ok(mk().path_ty(mk().path(vec!["libc", "c_ushort"]))),
CTypeKind::UInt => Ok(mk().path_ty(mk().path(vec!["libc", "c_uint"]))),
CTypeKind::ULong => Ok(mk().path_ty(mk().path(vec!["libc", "c_ulong"]))),
CTypeKind::ULongLong => Ok(mk().path_ty(mk().path(vec!["libc", "c_ulonglong"]))),
CTypeKind::SChar => Ok(mk().path_ty(mk().path(vec!["libc", "c_schar"]))),
CTypeKind::UChar => Ok(mk().path_ty(mk().path(vec!["libc", "c_uchar"]))),
CTypeKind::Char => Ok(mk().path_ty(mk().path(vec!["libc", "c_char"]))),
CTypeKind::Double => Ok(mk().path_ty(mk().path(vec!["libc", "c_double"]))),
CTypeKind::LongDouble => Ok(mk().path_ty(mk().path(vec!["f128", "f128"]))),
CTypeKind::Float => Ok(mk().path_ty(mk().path(vec!["libc", "c_float"]))),
CTypeKind::Int128 => Ok(mk().path_ty(mk().path(vec!["i128"]))),
CTypeKind::UInt128 => Ok(mk().path_ty(mk().path(vec!["u128"]))),
let kind = &ctxt.index(ctype).kind;
if let Some(ty) = self.convert_primitive_type_kind(kind) {
return Ok(ty);
}

match *kind {
CTypeKind::Pointer(qtype) => self.convert_pointer(ctxt, qtype),

CTypeKind::Elaborated(ref ctype) => self.convert(ctxt, *ctype),
Expand Down
1 change: 1 addition & 0 deletions c2rust-transpile/src/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -105,6 +105,7 @@ pub struct TranspilerConfig {
pub reorganize_definitions: bool,
pub enabled_warnings: HashSet<Diagnostic>,
pub emit_no_std: bool,
pub ctypes_prefix: String,
pub output_dir: Option<PathBuf>,
pub translate_const_macros: bool,
pub translate_fn_macros: bool,
Expand Down
6 changes: 5 additions & 1 deletion c2rust-transpile/src/translator/builtins.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -93,7 +93,7 @@ impl<'c> Translation<'c> {
Ok(val.map(|v| {
let val = mk().method_call_expr(v, "is_sign_negative", vec![] as Vec<P<Expr>>);

mk().cast_expr(val, mk().path_ty(vec!["libc", "c_int"]))
mk().cast_expr(val, self.convert_primitive_type_kind(&CTypeKind::Int))
}))
},
"__builtin_ffs" | "__builtin_ffsl" | "__builtin_ffsll" => {
Expand Down Expand Up @@ -246,6 +246,8 @@ impl<'c> Translation<'c> {
"__builtin_constant_p" => Ok(WithStmts::new_val(mk().lit_expr(mk().int_lit(0, "")))),

"__builtin_object_size" => {
self.use_crate(ExternCrate::Libc);

// We can't convert this to Rust, but it should be safe to always return -1/0
// (depending on the value of `type`), so we emit the following:
// `(if (type & 2) == 0 { -1isize } else { 0isize }) as libc::size_t`
Expand Down Expand Up @@ -670,6 +672,8 @@ impl<'c> Translation<'c> {
ctx: ExprContext,
args: &[CExprId],
) -> Result<WithStmts<P<Expr>>, TranslationError> {
self.use_crate(ExternCrate::Libc);

let name = &builtin_name[10..];
let mem = mk().path_expr(vec!["libc", name]);
let args = self.convert_exprs(ctx.used(), args)?;
Expand Down
4 changes: 2 additions & 2 deletions c2rust-transpile/src/translator/main_function.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -53,7 +53,7 @@ impl<'c> Translation<'c> {
Some(mk().path_ty(vec![mk().path_segment_with_args(
"Vec",
mk().angle_bracketed_args(vec![
mk().mutbl().ptr_ty(mk().path_ty(vec!["libc", "c_char"])),
mk().mutbl().ptr_ty(self.convert_primitive_type_kind(&CTypeKind::Char)),
]),
)])),
Some(
Expand Down Expand Up @@ -125,7 +125,7 @@ impl<'c> Translation<'c> {
Some(mk().path_ty(vec![mk().path_segment_with_args(
"Vec",
mk().angle_bracketed_args(vec![
mk().mutbl().ptr_ty(mk().path_ty(vec!["libc", "c_char"])),
mk().mutbl().ptr_ty(self.convert_primitive_type_kind(&CTypeKind::Char)),
]),
)])),
Some(
Expand Down
34 changes: 23 additions & 11 deletions c2rust-transpile/src/translator/mod.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -520,7 +520,9 @@ pub fn translate(

// `with_globals` sets up a thread-local variable required by the syntax crate.
with_globals(Edition::Edition2018, || {
t.use_crate(ExternCrate::Libc);
if t.tcfg.ctypes_prefix == "libc" {
t.use_crate(ExternCrate::Libc);
}

// Sort the top-level declarations by file and source location so that we
// preserve the ordering of all declarations in each file.
Expand Down Expand Up @@ -1033,11 +1035,6 @@ fn print_header(s: &mut pprust::State, t: &Translation, is_binary: bool) {
}
}

/// Convert a boolean expression to a c_int
fn bool_to_int(val: P<Expr>) -> P<Expr> {
mk().cast_expr(val, mk().path_ty(vec!["libc", "c_int"]))
}

/// Add a src_loc = "line:col" attribute to an item/foreign_item
fn add_src_loc_attr(attrs: &mut Vec<ast::Attribute>, src_loc: &Option<SrcLoc>) {
if let Some(src_loc) = src_loc.as_ref() {
Expand Down Expand Up @@ -1092,7 +1089,7 @@ impl<'c> Translation<'c> {
main_file: &path::Path,
) -> Self {
let comment_context = CommentContext::new(&mut ast_context);
let mut type_converter = TypeConverter::new(tcfg.emit_no_std);
let mut type_converter = TypeConverter::new(tcfg.emit_no_std, tcfg.ctypes_prefix.clone());

if tcfg.translate_valist {
type_converter.translate_valist = true
Expand Down Expand Up @@ -2786,6 +2783,21 @@ impl<'c> Translation<'c> {
.convert(&self.ast_context, type_id)
}

fn convert_primitive_type_kind(&self, kind: &CTypeKind) -> P<Ty> {
if self.tcfg.ctypes_prefix == "libc" {
self.use_crate(ExternCrate::Libc);
}
self.type_converter
.borrow()
.convert_primitive_type_kind(kind)
.unwrap()
}

/// Convert a boolean expression to a c_int
fn convert_bool_to_int(&self, val: P<Expr>) -> P<Expr> {
mk().cast_expr(val, self.convert_primitive_type_kind(&CTypeKind::Int))
}

/// Construct an expression for a NULL at any type, including forward declarations,
/// function pointers, and normal pointers.
fn null_ptr(&self, type_id: CTypeId, is_static: bool) -> Result<P<Expr>, TranslationError> {
Expand Down Expand Up @@ -3118,7 +3130,7 @@ impl<'c> Translation<'c> {
UnTypeOp::PreferredAlignOf => self.compute_align_of_type(arg_ty.ctype, true)?,
};

Ok(result.map(|x| mk().cast_expr(x, mk().path_ty(vec!["libc", "c_ulong"]))))
Ok(result.map(|x| mk().cast_expr(x, self.convert_primitive_type_kind(&CTypeKind::ULong))))
}

CExprKind::ConstantExpr(_ty, child, value) => {
Expand Down Expand Up @@ -4033,10 +4045,10 @@ impl<'c> Translation<'c> {
}
let target_ty = self.convert_type(ty.ctype)?;
val.and_then(|x| {
let intptr_t = mk().path_ty(vec!["libc", "intptr_t"]);
let intptr = mk().cast_expr(x, intptr_t.clone());
let usize_ty = mk().ident_ty("usize");
let intptr = mk().cast_expr(x, usize_ty.clone());
Ok(WithStmts::new_unsafe_val(
transmute_expr(intptr_t, target_ty, intptr, self.tcfg.emit_no_std)
transmute_expr(usize_ty, target_ty, intptr, self.tcfg.emit_no_std)
))
})
}
Expand Down
16 changes: 8 additions & 8 deletions c2rust-transpile/src/translator/operators.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -68,7 +68,7 @@ impl<'c> Translation<'c> {
let lhs = self.convert_condition(ctx, true, lhs)?;
let rhs = self.convert_condition(ctx, true, rhs)?;
lhs
.map(|x| bool_to_int(mk().binary_expr(BinOpKind::from(op), x, rhs.to_expr())))
.map(|x| self.convert_bool_to_int(mk().binary_expr(BinOpKind::from(op), x, rhs.to_expr())))
.and_then(|out| {
if ctx.is_unused() {
Ok(WithStmts::new(
Expand Down Expand Up @@ -655,7 +655,7 @@ impl<'c> Translation<'c> {
mk().binary_expr(BinOpKind::Eq, lhs, rhs)
};

Ok(bool_to_int(expr))
Ok(self.convert_bool_to_int(expr))
}
c_ast::BinOp::NotEqual => {
// Using is_some method for null comparison means we don't have to
Expand All @@ -677,12 +677,12 @@ impl<'c> Translation<'c> {
mk().binary_expr(BinOpKind::Ne, lhs, rhs)
};

Ok(bool_to_int(expr))
Ok(self.convert_bool_to_int(expr))
}
c_ast::BinOp::Less => Ok(bool_to_int(mk().binary_expr(BinOpKind::Lt, lhs, rhs))),
c_ast::BinOp::Greater => Ok(bool_to_int(mk().binary_expr(BinOpKind::Gt, lhs, rhs))),
c_ast::BinOp::GreaterEqual => Ok(bool_to_int(mk().binary_expr(BinOpKind::Ge, lhs, rhs))),
c_ast::BinOp::LessEqual => Ok(bool_to_int(mk().binary_expr(BinOpKind::Le, lhs, rhs))),
c_ast::BinOp::Less => Ok(self.convert_bool_to_int(mk().binary_expr(BinOpKind::Lt, lhs, rhs))),
c_ast::BinOp::Greater => Ok(self.convert_bool_to_int(mk().binary_expr(BinOpKind::Gt, lhs, rhs))),
c_ast::BinOp::GreaterEqual => Ok(self.convert_bool_to_int(mk().binary_expr(BinOpKind::Ge, lhs, rhs))),
c_ast::BinOp::LessEqual => Ok(self.convert_bool_to_int(mk().binary_expr(BinOpKind::Le, lhs, rhs))),

c_ast::BinOp::BitAnd => Ok(mk().binary_expr(BinOpKind::BitAnd, lhs, rhs)),
c_ast::BinOp::BitOr => Ok(mk().binary_expr(BinOpKind::BitOr, lhs, rhs)),
Expand Down Expand Up @@ -1031,7 +1031,7 @@ impl<'c> Translation<'c> {

c_ast::UnOp::Not => {
let val = self.convert_condition(ctx, false, arg)?;
Ok(val.map(|x| mk().cast_expr(x, mk().path_ty(vec!["libc", "c_int"]))))
Ok(val.map(|x| mk().cast_expr(x, self.convert_primitive_type_kind(&c_ast::CTypeKind::Int))))
}
c_ast::UnOp::Extension => {
let arg = self.convert_expr(ctx, arg)?;
Expand Down
2 changes: 1 addition & 1 deletion c2rust-transpile/src/translator/variadic.rs
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Expand Up @@ -147,7 +147,7 @@ impl<'c> Translation<'c> {
.map_or(false, |ty| self.ast_context.is_forward_declared_type(ty.ctype))
{
real_arg_ty = Some(arg_ty.clone());
arg_ty = mk().mutbl().ptr_ty(mk().path_ty(vec!["libc", "c_void"]));
arg_ty = mk().mutbl().ptr_ty(mk().path_ty(vec!["core", "ffi", "c_void"]));
}

val.and_then(|val| {
Expand Down
4 changes: 4 additions & 0 deletions c2rust/src/bin/c2rust-transpile.rs
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Expand Up @@ -112,6 +112,10 @@ fn main() {
},
replace_unsupported_decls: ReplaceMode::Extern,
emit_no_std: matches.is_present("emit-no-std"),
ctypes_prefix: matches
.value_of("ctypes-prefix")
.map(String::from)
.unwrap(),
enabled_warnings,
log_level,
};
Expand Down
11 changes: 11 additions & 0 deletions c2rust/src/transpile.yaml
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Expand Up @@ -168,6 +168,17 @@ args:
long: emit-no-std
help: Emit code using core rather than std
takes_value: false
requires: use-libc-types
- ctypes-prefix:
long: ctypes-prefix
help: Prefix to use for C types
takes_value: true
default_value: std::os::raw
# FIXME: clap has a bug parsing this which was fixed
# immediately after the release of 2.33.3; when 2.33.4
# comes out, this will work
#default_value_if:
# - ["emit-no-std", null, "libc"]
- disable-refactoring:
long: disable-refactoring
help: Disable running refactoring tool after translation
Expand Down
6 changes: 3 additions & 3 deletions tests/statics/src/test_sections.rs
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Expand Up @@ -43,14 +43,14 @@ pub fn test_sectioned_used_static() {

let pos = lines
.iter()
.position(|&x| x == "static mut rust_used_static4: libc::c_int = 1 as libc::c_int;")
.position(|&x| x == "static mut rust_used_static4: std::os::raw::c_int = 1 as std::os::raw::c_int;")
.expect("Did not find expected static string in source");
// The ordering of these attributes is not stable between LLVM versions
assert!((lines[pos-1] == "#[used]" && lines[pos-2] == "#[link_section = \"barz\"]") ||
(lines[pos-2] == "#[used]" && lines[pos-1] == "#[link_section = \"barz\"]"));

// This static is pub, but we want to ensure it has attributes applied
assert!(src.contains("#[link_section = \"fb\"]\npub static mut rust_initialized_extern: libc::c_int = 1 as libc::c_int;"));
assert!(src.contains("#[no_mangle]\n #[link_name = \"no_attrs\"]\n static mut rust_aliased_static: libc::c_int;"))
assert!(src.contains("#[link_section = \"fb\"]\npub static mut rust_initialized_extern: std::os::raw::c_int =\n 1 as std::os::raw::c_int;"));
assert!(src.contains("#[no_mangle]\n #[link_name = \"no_attrs\"]\n static mut rust_aliased_static: std::os::raw::c_int;"))
}
}