clang-tools 3.8.0

- Main Page
- Namespaces
- Classes
- Files

- File List
- File Members

NonCopyableObjects.cpp
Go to the documentation of this file.
1 //===--- NonCopyableObjects.cpp - clang-tidy-------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "NonCopyableObjects.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 #include <algorithm>
14
15 using namespace clang::ast_matchers;
16
17 namespace clang {
18 namespace {
19 // FIXME: it would be good to make a list that is also user-configurable so that
20 // users can add their own elements to the list. However, it may require some
21 // extra thought since POSIX types and FILE types are usable in different ways.
22 bool isPOSIXTypeName(StringRef ClassName) {
23 static const char *const TypeNames[] = {
24 "::pthread_cond_t",
25 "::pthread_mutex_t",
26 "pthread_cond_t",
27 "pthread_mutex_t"
28 };
29 return std::binary_search(std::begin(TypeNames), std::end(TypeNames),
30 ClassName);
31 }
32
33 bool isFILETypeName(StringRef ClassName) {
34 static const char *const TypeNames[] = {
35 "::FILE",
36 "FILE",
37 "std::FILE"
38 };
39 return std::binary_search(std::begin(TypeNames), std::end(TypeNames),
40 ClassName);
41 }
42
43 AST_MATCHER(NamedDecl, isFILEType) {
44 return isFILETypeName(Node.getQualifiedNameAsString());
45 }
46
47 AST_MATCHER(NamedDecl, isPOSIXType) {
48 return isPOSIXTypeName(Node.getQualifiedNameAsString());
49 }
50 } // namespace
51
52 namespace tidy {
53 void NonCopyableObjectsCheck::registerMatchers(MatchFinder *Finder) {
54 // There are two ways to get into trouble with objects like FILE *:
55 // dereferencing the pointer type to be a non-pointer type, and declaring
56 // the type as a non-pointer type in the first place. While the declaration
57 // itself could technically be well-formed in the case where the type is not
58 // an opaque type, it's highly suspicious behavior.
59 //
60 // POSIX types are a bit different in that it's reasonable to declare a
61 // non-pointer variable or data member of the type, but it is not reasonable
62 // to dereference a pointer to the type, or declare a parameter of non-pointer
63 // type.
64 auto BadFILEType = hasType(namedDecl(isFILEType()).bind("type_decl"));
65 auto BadPOSIXType = hasType(namedDecl(isPOSIXType()).bind("type_decl"));
66 auto BadEitherType = anyOf(BadFILEType, BadPOSIXType);
67
68 Finder->addMatcher(
69 namedDecl(anyOf(varDecl(BadFILEType), fieldDecl(BadFILEType)))
70 .bind("decl"),
71 this);
72 Finder->addMatcher(parmVarDecl(BadPOSIXType).bind("decl"), this);
73 Finder->addMatcher(
74 expr(unaryOperator(hasOperatorName("*"), BadEitherType)).bind("expr"),
75 this);
76 }
77
78 void NonCopyableObjectsCheck::check(const MatchFinder::MatchResult &Result) {
79 const auto *D = Result.Nodes.getNodeAs<NamedDecl>("decl");
80 const auto *BD = Result.Nodes.getNodeAs<NamedDecl>("type_decl");
81 const auto *E = Result.Nodes.getNodeAs<Expr>("expr");
82
83 if (D && BD)
84 diag(D->getLocation(), "'%0' declared as type '%1', which is unsafe to copy"
85 "; did you mean '%1 *'?")
86 << D->getName() << BD->getName();
87 else if (E)
88 diag(E->getExprLoc(),
89 "expression has opaque data structure type '%0'; type should only be "
90 "used as a pointer and not dereferenced")
91 << BD->getName();
92 }
93
94 } // namespace tidy
95 } // namespace clang
96
NonCopyableObjects.h
Finder
std::unique_ptr< ast_matchers::MatchFinder > Finder
Definition: ClangTidy.cpp:188
clang::tidy::AST_MATCHER
AST_MATCHER(Stmt, isInsideOfRangeBeginEndStmt)
Definition: ProBoundsArrayToPointerDecayCheck.cpp:25
Result
const NamedDecl * Result
Definition: USRFinder.cpp:121