1 use rustc_hir::{self as hir, intravisit, HirIdSet};
2 use rustc_lint::LateContext;
4 use rustc_span::def_id::LocalDefId;
6 use clippy_utils::diagnostics::span_lint;
7 use clippy_utils::ty::type_is_unsafe_function;
8 use clippy_utils::{iter_input_pats, path_to_local};
10 use super::NOT_UNSAFE_PTR_ARG_DEREF;
12 pub(super) fn check_fn<'tcx>(
13 cx: &LateContext<'tcx>,
14 kind: intravisit::FnKind<'tcx>,
15 decl: &'tcx hir::FnDecl<'tcx>,
16 body: &'tcx hir::Body<'tcx>,
19 let unsafety = match kind {
20 intravisit::FnKind::ItemFn(_, _, hir::FnHeader { unsafety, .. }, _) => unsafety,
21 intravisit::FnKind::Method(_, sig, _) => sig.header.unsafety,
22 intravisit::FnKind::Closure => return,
25 check_raw_ptr(cx, unsafety, decl, body, cx.tcx.hir().local_def_id(hir_id));
28 pub(super) fn check_trait_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::TraitItem<'_>) {
29 if let hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Provided(eid)) = item.kind {
30 let body = cx.tcx.hir().body(eid);
31 check_raw_ptr(cx, sig.header.unsafety, sig.decl, body, item.def_id);
35 fn check_raw_ptr<'tcx>(
36 cx: &LateContext<'tcx>,
37 unsafety: hir::Unsafety,
38 decl: &'tcx hir::FnDecl<'tcx>,
39 body: &'tcx hir::Body<'tcx>,
42 let expr = &body.value;
43 if unsafety == hir::Unsafety::Normal && cx.access_levels.is_exported(def_id) {
44 let raw_ptrs = iter_input_pats(decl, body)
45 .filter_map(|arg| raw_ptr_arg(cx, arg))
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(cx: &LateContext<'_>, arg: &hir::Param<'_>) -> Option<hir::HirId> {
62 if let (&hir::PatKind::Binding(_, id, _, _), Some(&ty::RawPtr(_))) = (
64 cx.maybe_typeck_results()
65 .map(|typeck_results| typeck_results.pat_ty(arg.pat).kind()),
73 struct DerefVisitor<'a, 'tcx> {
74 cx: &'a LateContext<'tcx>,
76 typeck_results: &'a ty::TypeckResults<'tcx>,
79 impl<'a, 'tcx> intravisit::Visitor<'tcx> for DerefVisitor<'a, 'tcx> {
80 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
82 hir::ExprKind::Call(f, args) => {
83 let ty = self.typeck_results.expr_ty(f);
85 if type_is_unsafe_function(self.cx, ty) {
91 hir::ExprKind::MethodCall(_, args, _) => {
92 let def_id = self.typeck_results.type_dependent_def_id(expr.hir_id).unwrap();
93 let base_type = self.cx.tcx.type_of(def_id);
95 if type_is_unsafe_function(self.cx, base_type) {
101 hir::ExprKind::Unary(hir::UnOp::Deref, ptr) => self.check_arg(ptr),
105 intravisit::walk_expr(self, expr);
109 impl<'a, 'tcx> DerefVisitor<'a, 'tcx> {
110 fn check_arg(&self, ptr: &hir::Expr<'_>) {
111 if let Some(id) = path_to_local(ptr) {
112 if self.ptrs.contains(&id) {
115 NOT_UNSAFE_PTR_ARG_DEREF,
117 "this public function might dereference a raw pointer but is not marked `unsafe`",