[clang-tidy] Use CloexecCheck as base class.

Summary:
Simplify registerMatchers and check functions in CloexecCreatCheck,
CloexecSocketCheck, CloexecFopenCheck, and CloexecOpenCheck.

Differential Revision: https://reviews.llvm.org/D36761

llvm-svn: 311020
diff --git a/clang-tools-extra/clang-tidy/android/CloexecCreatCheck.cpp b/clang-tools-extra/clang-tidy/android/CloexecCreatCheck.cpp
index 9b6ccf2..83ca49a 100644
--- a/clang-tools-extra/clang-tidy/android/CloexecCreatCheck.cpp
+++ b/clang-tools-extra/clang-tidy/android/CloexecCreatCheck.cpp
@@ -10,7 +10,6 @@
 #include "CloexecCreatCheck.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
-#include "clang/Lex/Lexer.h"
 
 using namespace clang::ast_matchers;
 
@@ -21,37 +20,22 @@
 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);
+  registerMatchersImpl(Finder,
+                       functionDecl(isExternC(), returns(isInteger()),
+                                    hasName("creat"),
+                                    hasParameter(0, CharPointerType),
+                                    hasParameter(1, MODETType)));
 }
 
 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()) +
+      (Twine("open (") + getSpellingArg(Result, 0) +
        ", O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC, " +
-       Lexer::getSourceText(CharSourceRange::getTokenRange(
-                                MatchedCall->getArg(1)->getSourceRange()),
-                            SM, Result.Context->getLangOpts()) +
-       ")")
+       getSpellingArg(Result, 1) + ")")
           .str();
-
-  diag(MatchedCall->getLocStart(),
-       "prefer open() to creat() because open() allows O_CLOEXEC")
-      << FixItHint::CreateReplacement(MatchedCall->getSourceRange(),
-                                      ReplacementText);
+  replaceFunc(Result,
+              "prefer open() to creat() because open() allows O_CLOEXEC",
+              ReplacementText);
 }
 
 } // namespace android