1 files changed, 67 insertions, 0 deletions
diff --git a/clang-tools-extra/clang-tidy/misc/NonCopyableObjectsCheck.cpp b/clang-tools-extra/clang-tidy/misc/NonCopyableObjectsCheck.cpp
new file mode 100644
index 0000000..bfeb5fa
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/misc/NonCopyableObjectsCheck.cpp
@@ -0,0 +1,67 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "NonCopyableObjectsCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::misc {
+
+void NonCopyableObjectsCheck::registerMatchers(MatchFinder *Finder) {
+  // There are two ways to get into trouble with objects like FILE *:
+  // dereferencing the pointer type to be a non-pointer type, and declaring
+  // the type as a non-pointer type in the first place. While the declaration
+  // itself could technically be well-formed in the case where the type is not
+  // an opaque type, it's highly suspicious behavior.
+  //
+  // POSIX types are a bit different in that it's reasonable to declare a
+  // non-pointer variable or data member of the type, but it is not reasonable
+  // to dereference a pointer to the type, or declare a parameter of non-pointer
+  // type.
+  // FIXME: it would be good to make a list that is also user-configurable so
+  // that users can add their own elements to the list. However, it may require
+  // some extra thought since POSIX types and FILE types are usable in different
+  // ways.
+
+  auto BadFILEType = hasType(
+      namedDecl(hasAnyName("::FILE", "FILE", "std::FILE")).bind("type_decl"));
+  auto BadPOSIXType =
+      hasType(namedDecl(hasAnyName("::pthread_cond_t", "::pthread_mutex_t",
+                                   "pthread_cond_t", "pthread_mutex_t"))
+                  .bind("type_decl"));
+  auto BadEitherType = anyOf(BadFILEType, BadPOSIXType);
+
+  Finder->addMatcher(
+      namedDecl(anyOf(varDecl(BadFILEType), fieldDecl(BadFILEType)))
+          .bind("decl"),
+      this);
+  Finder->addMatcher(parmVarDecl(BadPOSIXType).bind("decl"), this);
+  Finder->addMatcher(
+      expr(unaryOperator(hasOperatorName("*"), BadEitherType)).bind("expr"),
+      this);
+}
+
+void NonCopyableObjectsCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *D = Result.Nodes.getNodeAs<NamedDecl>("decl");
+  const auto *BD = Result.Nodes.getNodeAs<NamedDecl>("type_decl");
+  const auto *E = Result.Nodes.getNodeAs<Expr>("expr");
+
+  if (D && BD)
+    diag(D->getLocation(), "%0 declared as type '%1', which is unsafe to copy"
+                           "; did you mean '%1 *'?")
+        << D << BD->getName();
+  else if (E)
+    diag(E->getExprLoc(),
+         "expression has opaque data structure type %0; type should only be "
+         "used as a pointer and not dereferenced")
+        << BD;
+}
+
+} // namespace clang::tidy::misc