1 use rustc_hir::{self as hir, intravisit, HirIdSet};
2 use rustc_lint::LateContext;
3 use rustc_middle::{hir::map::Map, ty};
5 use clippy_utils::diagnostics::span_lint;
6 use clippy_utils::ty::type_is_unsafe_function;
7 use clippy_utils::{iter_input_pats, path_to_local};
9 use super::NOT_UNSAFE_PTR_ARG_DEREF;
11 pub(super) fn check_fn(
12 cx: &LateContext<'tcx>,
13 kind: intravisit::FnKind<'tcx>,
14 decl: &'tcx hir::FnDecl<'tcx>,
15 body: &'tcx hir::Body<'tcx>,
18 let unsafety = match kind {
19 intravisit::FnKind::ItemFn(_, _, hir::FnHeader { unsafety, .. }, _) => unsafety,
20 intravisit::FnKind::Method(_, sig, _) => sig.header.unsafety,
21 intravisit::FnKind::Closure => return,
24 check_raw_ptr(cx, unsafety, decl, body, hir_id);
27 pub(super) fn check_trait_item(cx: &LateContext<'tcx>, item: &'tcx hir::TraitItem<'_>) {
28 if let hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Provided(eid)) = item.kind {
29 let body = cx.tcx.hir().body(eid);
30 check_raw_ptr(cx, sig.header.unsafety, sig.decl, body, item.hir_id());
35 cx: &LateContext<'tcx>,
36 unsafety: hir::Unsafety,
37 decl: &'tcx hir::FnDecl<'tcx>,
38 body: &'tcx hir::Body<'tcx>,
41 let expr = &body.value;
42 if unsafety == hir::Unsafety::Normal && cx.access_levels.is_exported(hir_id) {
43 let raw_ptrs = iter_input_pats(decl, body)
44 .zip(decl.inputs.iter())
45 .filter_map(|(arg, ty)| raw_ptr_arg(arg, ty))
46 .collect::<HirIdSet>();
48 if !raw_ptrs.is_empty() {
49 let typeck_results = cx.tcx.typeck_body(body.id());
50 let mut v = DerefVisitor {
56 intravisit::walk_expr(&mut v, expr);
61 fn raw_ptr_arg(arg: &hir::Param<'_>, ty: &hir::Ty<'_>) -> Option<hir::HirId> {
62 if let (&hir::PatKind::Binding(_, id, _, _), &hir::TyKind::Ptr(_)) = (&arg.pat.kind, &ty.kind) {
69 struct DerefVisitor<'a, 'tcx> {
70 cx: &'a LateContext<'tcx>,
72 typeck_results: &'a ty::TypeckResults<'tcx>,
75 impl<'a, 'tcx> intravisit::Visitor<'tcx> for DerefVisitor<'a, 'tcx> {
78 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
80 hir::ExprKind::Call(f, args) => {
81 let ty = self.typeck_results.expr_ty(f);
83 if type_is_unsafe_function(self.cx, ty) {
89 hir::ExprKind::MethodCall(_, _, args, _) => {
90 let def_id = self.typeck_results.type_dependent_def_id(expr.hir_id).unwrap();
91 let base_type = self.cx.tcx.type_of(def_id);
93 if type_is_unsafe_function(self.cx, base_type) {
99 hir::ExprKind::Unary(hir::UnOp::Deref, ptr) => self.check_arg(ptr),
103 intravisit::walk_expr(self, expr);
106 fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
107 intravisit::NestedVisitorMap::None
111 impl<'a, 'tcx> DerefVisitor<'a, 'tcx> {
112 fn check_arg(&self, ptr: &hir::Expr<'_>) {
113 if let Some(id) = path_to_local(ptr) {
114 if self.ptrs.contains(&id) {
117 NOT_UNSAFE_PTR_ARG_DEREF,
119 "this public function dereferences a raw pointer but is not marked `unsafe`",