[clang-tidy][Part2] Add a new module Android and three new checks

Summary: -- creat() should be replaced by open(). [android-creat-usage] 

Reviewers: chh, alexfh, aaron.ballman, hokein

Reviewed By: hokein

Subscribers: JDevlieghere, srhines, mgorny, xazax.hun

Tags: #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D33745

llvm-svn: 306708
diff --git a/clang-tools-extra/clang-tidy/android/CloexecCreatCheck.cpp b/clang-tools-extra/clang-tidy/android/CloexecCreatCheck.cpp
new file mode 100644
index 0000000..9b6ccf2
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/android/CloexecCreatCheck.cpp
@@ -0,0 +1,59 @@
+//===--- CloexecCreatCheck.cpp - clang-tidy--------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CloexecCreatCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace android {
+
+void CloexecCreatCheck::registerMatchers(MatchFinder *Finder) {
+  auto CharPointerType = hasType(pointerType(pointee(isAnyCharacter())));
+  auto MODETType = hasType(namedDecl(hasName("mode_t")));
+
+  Finder->addMatcher(
+      callExpr(callee(functionDecl(isExternC(), returns(isInteger()),
+                                   hasName("creat"),
+                                   hasParameter(0, CharPointerType),
+                                   hasParameter(1, MODETType))
+                          .bind("funcDecl")))
+          .bind("creatFn"),
+      this);
+}
+
+void CloexecCreatCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *MatchedCall = Result.Nodes.getNodeAs<CallExpr>("creatFn");
+  const SourceManager &SM = *Result.SourceManager;
+
+  const std::string &ReplacementText =
+      (Twine("open (") +
+       Lexer::getSourceText(CharSourceRange::getTokenRange(
+                                MatchedCall->getArg(0)->getSourceRange()),
+                            SM, Result.Context->getLangOpts()) +
+       ", O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC, " +
+       Lexer::getSourceText(CharSourceRange::getTokenRange(
+                                MatchedCall->getArg(1)->getSourceRange()),
+                            SM, Result.Context->getLangOpts()) +
+       ")")
+          .str();
+
+  diag(MatchedCall->getLocStart(),
+       "prefer open() to creat() because open() allows O_CLOEXEC")
+      << FixItHint::CreateReplacement(MatchedCall->getSourceRange(),
+                                      ReplacementText);
+}
+
+} // namespace android
+} // namespace tidy
+} // namespace clang