Index: clang-tidy/CMakeLists.txt
===================================================================
--- clang-tidy/CMakeLists.txt
+++ clang-tidy/CMakeLists.txt
@@ -40,3 +40,4 @@
 add_subdirectory(readability)
 add_subdirectory(tool)
 add_subdirectory(utils)
+add_subdirectory(android)
Index: clang-tidy/android/AndroidTidyModule.cpp
===================================================================
--- clang-tidy/android/AndroidTidyModule.cpp
+++ clang-tidy/android/AndroidTidyModule.cpp
@@ -0,0 +1,53 @@
+//===--- AndroidTidyModule.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 "FileDescriptorCheck.h"
+#include "../ClangTidy.h"
+#include "../ClangTidyModule.h"
+#include "../ClangTidyModuleRegistry.h"
+#include "../readability/BracesAroundStatementsCheck.h"
+#include "../readability/FunctionSizeCheck.h"
+#include "../readability/NamespaceCommentCheck.h"
+#include "../readability/RedundantSmartptrGetCheck.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace android {
+
+/// This module is for Android specific checks.
+
+class AndroidModule : public ClangTidyModule {
+public:
+  void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override {
+    CheckFactories.registerCheck<FileDescriptorCheck>(
+        "android-file-descriptor");
+  }
+
+  ClangTidyOptions getModuleOptions() override {
+    ClangTidyOptions Options;
+    // auto &Opts = Options.CheckOptions;
+    return Options;
+  }
+};
+
+// Register the AndroidTidyModule using this statically initialized variable.
+static ClangTidyModuleRegistry::Add<AndroidModule>
+    X("android-module", "Adds Andrdoid lint checks.");
+
+} // namespace android
+
+// This anchor is used to force the linker to link in the generated object file
+// and thus register the AndroidModule.
+volatile int AndroidModuleAnchorSource = 0;
+
+} // namespace tidy
+} // namespace clang
Index: clang-tidy/android/CMakeLists.txt
===================================================================
--- clang-tidy/android/CMakeLists.txt
+++ clang-tidy/android/CMakeLists.txt
@@ -0,0 +1,15 @@
+set(LLVM_LINK_COMPONENTS support)
+
+add_clang_library(clangTidyAndroidModule
+  AndroidTidyModule.cpp
+  FileDescriptorCheck.cpp
+
+  LINK_LIBS
+  clangAST
+  clangASTMatchers
+  clangBasic
+  clangLex
+  clangTidy
+  clangTidyReadabilityModule
+  clangTidyUtils
+  )
Index: clang-tidy/android/FileDescriptorCheck.h
===================================================================
--- clang-tidy/android/FileDescriptorCheck.h
+++ clang-tidy/android/FileDescriptorCheck.h
@@ -0,0 +1,45 @@
+//===--- FileDescriptorCheck.h - clang-tidy----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_FILE_DESCRIPTOR_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_FILE_DESCRIPTOR_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace android {
+
+/// Finds code that opens file descriptors without using the O_CLOEXEC flag.
+///
+/// open(), openat(), and open64() must include O_CLOEXEC in their flags
+/// argument.
+/// Only consider simple cases that the corresponding argument is constant or
+/// binary operation OR among constants like 'O_CLOEXEC' or 'O_CLOEXEC |
+/// O_RDONLY'. No constant propagation is performed.
+
+class FileDescriptorCheck : public ClangTidyCheck {
+public:
+  FileDescriptorCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+  bool checkFlags(const Expr *Flags);
+  bool checkFlag(const IntegerLiteral *Flag);
+
+private:
+  static constexpr const char *FLAG = "O_CLOEXEC";
+  static constexpr const char *HEADER_FILE = "fcntl.h";
+};
+
+} // namespace android
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_FILE_DESCRIPTOR_H
Index: clang-tidy/android/FileDescriptorCheck.cpp
===================================================================
--- clang-tidy/android/FileDescriptorCheck.cpp
+++ clang-tidy/android/FileDescriptorCheck.cpp
@@ -0,0 +1,102 @@
+//===--- FileDescriptorCheck.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 "FileDescriptorCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Lex/Lexer.h"
+#include <fcntl.h>
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace android {
+
+void FileDescriptorCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(
+      callExpr(
+          callee(functionDecl(allOf(
+              isExpansionInFileMatching(HEADER_FILE), returns(asString("int")),
+              hasParameter(1, hasType(isInteger())),
+              anyOf(matchesName("open"), matchesName("open64")))).bind("funcDecl")))
+          .bind("openFn"),
+      this);
+  Finder->addMatcher(
+      callExpr(callee(functionDecl(allOf(isExpansionInFileMatching(HEADER_FILE),
+                                         returns(asString("int")),
+                                         hasParameter(2, hasType(isInteger())),
+                                         matchesName("openat"))).bind("funcDecl")))
+          .bind("openatFn"),
+      this);
+}
+
+void FileDescriptorCheck::check(const MatchFinder::MatchResult &Result) {
+  SourceManager &SM = *Result.SourceManager;
+  LangOptions LangOpts = getLangOpts();
+  const CallExpr *MatchedCall;
+  const Expr *FlagArg;
+  if (MatchedCall = Result.Nodes.getNodeAs<CallExpr>("openFn")) {
+    FlagArg = MatchedCall->getArg(1);
+  } else if (MatchedCall = Result.Nodes.getNodeAs<CallExpr>("openatFn")) {
+    FlagArg = MatchedCall->getArg(2);
+  } else {
+    return;
+  }
+
+  const auto *FD = Result.Nodes.getNodeAs<FunctionDecl>("funcDecl");
+
+  if (!checkFlags(FlagArg)) {
+    SourceRange FlagsRange(FlagArg->getLocStart(), FlagArg->getLocEnd());
+
+    StringRef FlagsText = Lexer::getSourceText(
+        CharSourceRange::getTokenRange(FlagsRange), SM, LangOpts);
+
+    std::string ReplacementText =
+        (llvm::Twine(FlagsText) + " | " + FileDescriptorCheck::FLAG).str();
+
+    diag(FlagArg->getLocStart(),
+         "%0 must include O_CLOEXEC in their flags argument.")
+        << FD->getName()
+        << FixItHint::CreateReplacement(FlagsRange, ReplacementText);
+  }
+}
+
+// Check if a constant flag contains required flag.
+bool FileDescriptorCheck::checkFlag(const IntegerLiteral *Flag) {
+  llvm::APInt aPInt = Flag->getValue();
+  if (aPInt.isSignedIntN(aPInt.getBitWidth())) {
+    int64_t val = aPInt.getSExtValue();
+    if ((val & O_CLOEXEC) != O_CLOEXEC)
+      return false;
+  } else {
+    uint64_t val = aPInt.getZExtValue();
+    if ((val & O_CLOEXEC) != O_CLOEXEC)
+      return false;
+  }
+  return true;
+}
+
+// Check if flags contain required flag.
+bool FileDescriptorCheck::checkFlags(const Expr *Flags) {
+  if (isa<IntegerLiteral>(Flags)) {
+    return checkFlag(cast<IntegerLiteral>(Flags));
+  } else if (isa<BinaryOperator>(Flags)) {
+    if (cast<BinaryOperator>(Flags)->getOpcode() ==
+        clang::BinaryOperatorKind::BO_Or) {
+      return checkFlags(cast<BinaryOperator>(Flags)->getLHS()) ||
+             checkFlags(cast<BinaryOperator>(Flags)->getRHS());
+    }
+  }
+  return false;
+}
+
+} // namespace android
+} // namespace tidy
+} // namespace clang
Index: clang-tidy/plugin/CMakeLists.txt
===================================================================
--- clang-tidy/plugin/CMakeLists.txt
+++ clang-tidy/plugin/CMakeLists.txt
@@ -8,6 +8,7 @@
   clangFrontend
   clangSema
   clangTidy
+  clangTidyAndroidModule
   clangTidyBoostModule
   clangTidyCERTModule
   clangTidyCppCoreGuidelinesModule
Index: clang-tidy/tool/CMakeLists.txt
===================================================================
--- clang-tidy/tool/CMakeLists.txt
+++ clang-tidy/tool/CMakeLists.txt
@@ -13,6 +13,7 @@
   clangASTMatchers
   clangBasic
   clangTidy
+  clangTidyAndroidModule
   clangTidyBoostModule
   clangTidyCERTModule
   clangTidyCppCoreGuidelinesModule
Index: clang-tidy/tool/ClangTidyMain.cpp
===================================================================
--- clang-tidy/tool/ClangTidyMain.cpp
+++ clang-tidy/tool/ClangTidyMain.cpp
@@ -477,6 +477,11 @@
 static int LLVM_ATTRIBUTE_UNUSED GoogleModuleAnchorDestination =
     GoogleModuleAnchorSource;
 
+// This anchor is used to force the linker to link the AndroidModule.
+extern volatile int AndroidModuleAnchorSource;
+static int LLVM_ATTRIBUTE_UNUSED AndroidModuleAnchorDestination =
+    AndroidModuleAnchorSource;
+
 // This anchor is used to force the linker to link the MiscModule.
 extern volatile int MiscModuleAnchorSource;
 static int LLVM_ATTRIBUTE_UNUSED MiscModuleAnchorDestination =
Index: test/clang-tidy/android-file-descriptor.cpp
===================================================================
--- test/clang-tidy/android-file-descriptor.cpp
+++ test/clang-tidy/android-file-descriptor.cpp
@@ -0,0 +1,54 @@
+// RUN: %check_clang_tidy %s android-file-descriptor %t
+
+#include <fcntl.h>
+
+void a() {
+  open("filename", O_RDWR);
+  // CHECK-MESSAGES: :[[@LINE-1]]:20: warning: open must include O_CLOEXEC in their flags argument. [android-file-descriptor]
+  // CHECK-FIXES: O_RDWR | O_CLOEXEC
+  open("filename", O_RDWR | O_EXCL);
+  // CHECK-MESSAGES: :[[@LINE-1]]:20: warning: open must include O_CLOEXEC in their flags argument. [android-file-descriptor]
+  // CHECK-FIXES: O_RDWR | O_EXCL | O_CLOEXEC
+}
+
+void b() {
+  open64("filename", O_RDWR);
+  // CHECK-MESSAGES: :[[@LINE-1]]:22: warning: open64 must include O_CLOEXEC in their flags argument. [android-file-descriptor]
+  // CHECK-FIXES: O_RDWR | O_CLOEXEC
+  open64("filename", O_RDWR | O_EXCL);
+  // CHECK-MESSAGES: :[[@LINE-1]]:22: warning: open64 must include O_CLOEXEC in their flags argument. [android-file-descriptor]
+  // CHECK-FIXES: O_RDWR | O_EXCL | O_CLOEXEC
+}
+
+void c() {
+  openat(0, "filename", O_RDWR);
+  // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: openat must include O_CLOEXEC in their flags argument. [android-file-descriptor]
+  // CHECK-FIXES: O_RDWR | O_CLOEXEC
+  openat(0, "filename", O_RDWR | O_EXCL);
+  // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: openat must include O_CLOEXEC in their flags argument. [android-file-descriptor]
+  // CHECK-FIXES: O_RDWR | O_EXCL | O_CLOEXEC
+}
+
+namespace i {
+int open(const char *pathname, int flags) { return 0; }
+int open(const char *pathname, int flags, mode_t mode) { return 0; }
+int open64(const char *pathname, int flags) { return 0; }
+int open64(const char *pathname, int flags, mode_t mode) { return 0; }
+int openat(int dirfd, const char *pathname, int flags) { return 0; }
+int openat(int dirfd, const char *pathname, int flags, mode_t mode) { return 0; }
+} // namespace i
+
+void d() {
+  i::open("filename", O_RDWR);
+  i::open64("filename", O_RDWR);
+  i::openat(0, "filename", O_RDWR);
+}
+
+void e() {
+  open("filename", O_CLOEXEC);
+  open("filename", O_RDWR | O_CLOEXEC);
+  open64("filename", O_CLOEXEC);
+  open64("filename", O_RDWR | O_CLOEXEC);
+  openat(0, "filename", O_CLOEXEC);
+  openat(0, "filename", O_RDWR | O_CLOEXEC);
+}
Index: unittests/clang-tidy/CMakeLists.txt
===================================================================
--- unittests/clang-tidy/CMakeLists.txt
+++ unittests/clang-tidy/CMakeLists.txt
@@ -26,6 +26,7 @@
   clangLex
   clangTidy
   clangTidyGoogleModule
+  clangTidyAndroidModule
   clangTidyLLVMModule
   clangTidyMiscModule
   clangTidyReadabilityModule