clang-tools-extra/clang-tidy/cert/LimitedRandomnessCheck.cpp

   1 //===--- LimitedRandomnessCheck.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 "LimitedRandomnessCheck.h"
  10 #include "clang/AST/ASTContext.h"
  11 #include "clang/ASTMatchers/ASTMatchFinder.h"
  12
  13 using namespace clang::ast_matchers;
  14
  15 namespace clang::tidy::cert {
  16
  17 void LimitedRandomnessCheck::registerMatchers(MatchFinder *Finder) {
  18   Finder->addMatcher(callExpr(callee(functionDecl(namedDecl(hasName("::rand")),
  19                                                   parameterCountIs(0))))
  20                          .bind("randomGenerator"),
  21                      this);
  22 }
  23
  24 void LimitedRandomnessCheck::check(const MatchFinder::MatchResult &Result) {
  25   std::string Msg;
  26   if (getLangOpts().CPlusPlus)
  27     Msg = "; use C++11 random library instead";
  28
  29   const auto *MatchedDecl = Result.Nodes.getNodeAs<CallExpr>("randomGenerator");
  30   diag(MatchedDecl->getBeginLoc(), "rand() has limited randomness" + Msg);
  31 }
  32
  33 } // namespace clang::tidy::cert