1 //== CheckerContext.cpp - Context info for path-sensitive checkers-----------=//
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 // This file defines CheckerContext that provides contextual info for
11 // path-sensitive checkers.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
16 #include "clang/Basic/Builtins.h"
17 #include "clang/Lex/Lexer.h"
18
19 using namespace clang;
20 using namespace ento;
21
getCalleeDecl(const CallExpr * CE) const22 const FunctionDecl *CheckerContext::getCalleeDecl(const CallExpr *CE) const {
23 ProgramStateRef State = getState();
24 const Expr *Callee = CE->getCallee();
25 SVal L = State->getSVal(Callee, Pred->getLocationContext());
26 return L.getAsFunctionDecl();
27 }
28
getCalleeName(const FunctionDecl * FunDecl) const29 StringRef CheckerContext::getCalleeName(const FunctionDecl *FunDecl) const {
30 if (!FunDecl)
31 return StringRef();
32 IdentifierInfo *funI = FunDecl->getIdentifier();
33 if (!funI)
34 return StringRef();
35 return funI->getName();
36 }
37
getDeclDescription(const Decl * D)38 StringRef CheckerContext::getDeclDescription(const Decl *D) {
39 if (isa<ObjCMethodDecl>(D) || isa<CXXMethodDecl>(D))
40 return "method";
41 if (isa<BlockDecl>(D))
42 return "anonymous block";
43 return "function";
44 }
45
isCLibraryFunction(const FunctionDecl * FD,StringRef Name)46 bool CheckerContext::isCLibraryFunction(const FunctionDecl *FD,
47 StringRef Name) {
48 // To avoid false positives (Ex: finding user defined functions with
49 // similar names), only perform fuzzy name matching when it's a builtin.
50 // Using a string compare is slow, we might want to switch on BuiltinID here.
51 unsigned BId = FD->getBuiltinID();
52 if (BId != 0) {
53 if (Name.empty())
54 return true;
55 StringRef BName = FD->getASTContext().BuiltinInfo.getName(BId);
56 if (BName.find(Name) != StringRef::npos)
57 return true;
58 }
59
60 const IdentifierInfo *II = FD->getIdentifier();
61 // If this is a special C++ name without IdentifierInfo, it can't be a
62 // C library function.
63 if (!II)
64 return false;
65
66 // Look through 'extern "C"' and anything similar invented in the future.
67 // If this function is not in TU directly, it is not a C library function.
68 if (!FD->getDeclContext()->getRedeclContext()->isTranslationUnit())
69 return false;
70
71 // If this function is not externally visible, it is not a C library function.
72 // Note that we make an exception for inline functions, which may be
73 // declared in header files without external linkage.
74 if (!FD->isInlined() && !FD->isExternallyVisible())
75 return false;
76
77 if (Name.empty())
78 return true;
79
80 StringRef FName = II->getName();
81 if (FName.equals(Name))
82 return true;
83
84 if (FName.startswith("__inline") && (FName.find(Name) != StringRef::npos))
85 return true;
86
87 if (FName.startswith("__") && FName.endswith("_chk") &&
88 FName.find(Name) != StringRef::npos)
89 return true;
90
91 return false;
92 }
93
getMacroNameOrSpelling(SourceLocation & Loc)94 StringRef CheckerContext::getMacroNameOrSpelling(SourceLocation &Loc) {
95 if (Loc.isMacroID())
96 return Lexer::getImmediateMacroName(Loc, getSourceManager(),
97 getLangOpts());
98 SmallVector<char, 16> buf;
99 return Lexer::getSpelling(Loc, buf, getSourceManager(), getLangOpts());
100 }
101
102