| 1 | //===--- AvoidNonConstGlobalVariablesCheck.cpp - clang-tidy ---------------===// |
|---|
| 2 | // |
|---|
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
|---|
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
|---|
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
|---|
| 6 | // |
|---|
| 7 | //===----------------------------------------------------------------------===// |
|---|
| 8 | |
|---|
| 9 | #include "AvoidNonConstGlobalVariablesCheck.h" |
|---|
| 10 | #include "clang/AST/ASTContext.h" |
|---|
| 11 | #include "clang/ASTMatchers/ASTMatchFinder.h" |
|---|
| 12 | #include "clang/ASTMatchers/ASTMatchers.h" |
|---|
| 13 | |
|---|
| 14 | using namespace clang::ast_matchers; |
|---|
| 15 | |
|---|
| 16 | namespace clang::tidy::cppcoreguidelines { |
|---|
| 17 | |
|---|
| 18 | void AvoidNonConstGlobalVariablesCheck::registerMatchers(MatchFinder *Finder) { |
|---|
| 19 | auto GlobalContext = |
|---|
| 20 | varDecl(hasGlobalStorage(), |
|---|
| 21 | hasDeclContext(InnerMatcher: anyOf(namespaceDecl(), translationUnitDecl()))); |
|---|
| 22 | |
|---|
| 23 | auto GlobalVariable = varDecl( |
|---|
| 24 | GlobalContext, |
|---|
| 25 | unless(anyOf( |
|---|
| 26 | isConstexpr(), hasType(InnerMatcher: isConstQualified()), |
|---|
| 27 | hasType(InnerMatcher: referenceType())))); // References can't be changed, only the |
|---|
| 28 | // data they reference can be changed. |
|---|
| 29 | |
|---|
| 30 | auto GlobalReferenceToNonConst = |
|---|
| 31 | varDecl(GlobalContext, hasType(InnerMatcher: referenceType()), |
|---|
| 32 | unless(hasType(InnerMatcher: references(InnerMatcher: qualType(isConstQualified()))))); |
|---|
| 33 | |
|---|
| 34 | auto GlobalPointerToNonConst = varDecl( |
|---|
| 35 | GlobalContext, hasType(InnerMatcher: pointerType(pointee(unless(isConstQualified()))))); |
|---|
| 36 | |
|---|
| 37 | Finder->addMatcher(NodeMatch: GlobalVariable.bind(ID: "non-const_variable" ), Action: this); |
|---|
| 38 | Finder->addMatcher(NodeMatch: GlobalReferenceToNonConst.bind(ID: "indirection_to_non-const" ), |
|---|
| 39 | Action: this); |
|---|
| 40 | Finder->addMatcher(NodeMatch: GlobalPointerToNonConst.bind(ID: "indirection_to_non-const" ), |
|---|
| 41 | Action: this); |
|---|
| 42 | } |
|---|
| 43 | |
|---|
| 44 | void AvoidNonConstGlobalVariablesCheck::check( |
|---|
| 45 | const MatchFinder::MatchResult &Result) { |
|---|
| 46 | |
|---|
| 47 | if (const auto *Variable = |
|---|
| 48 | Result.Nodes.getNodeAs<VarDecl>(ID: "non-const_variable" )) { |
|---|
| 49 | diag(Variable->getLocation(), "variable %0 is non-const and globally " |
|---|
| 50 | "accessible, consider making it const" ) |
|---|
| 51 | << Variable; // FIXME: Add fix-it hint to Variable |
|---|
| 52 | // Don't return early, a non-const variable may also be a pointer or |
|---|
| 53 | // reference to non-const data. |
|---|
| 54 | } |
|---|
| 55 | |
|---|
| 56 | if (const auto *VD = |
|---|
| 57 | Result.Nodes.getNodeAs<VarDecl>(ID: "indirection_to_non-const" )) { |
|---|
| 58 | diag(VD->getLocation(), |
|---|
| 59 | "variable %0 provides global access to a non-const object; consider " |
|---|
| 60 | "making the %select{referenced|pointed-to}1 data 'const'" ) |
|---|
| 61 | << VD |
|---|
| 62 | << VD->getType()->isPointerType(); // FIXME: Add fix-it hint to Variable |
|---|
| 63 | } |
|---|
| 64 | } |
|---|
| 65 | |
|---|
| 66 | } // namespace clang::tidy::cppcoreguidelines |
|---|
| 67 | |
|---|
