1 //===--- HeaderGuardCheck.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 "HeaderGuardCheck.h"
10 #include "clang/Tooling/Tooling.h"
11 
12 namespace clang {
13 namespace tidy {
14 namespace llvm_check {
15 
LLVMHeaderGuardCheck(StringRef Name,ClangTidyContext * Context)16 LLVMHeaderGuardCheck::LLVMHeaderGuardCheck(StringRef Name,
17                                            ClangTidyContext *Context)
18     : HeaderGuardCheck(Name, Context) {}
19 
getHeaderGuard(StringRef Filename,StringRef OldGuard)20 std::string LLVMHeaderGuardCheck::getHeaderGuard(StringRef Filename,
21                                                  StringRef OldGuard) {
22   std::string Guard = tooling::getAbsolutePath(Filename);
23 
24   // Sanitize the path. There are some rules for compatibility with the historic
25   // style in include/llvm and include/clang which we want to preserve.
26 
27   // We don't want _INCLUDE_ in our guards.
28   size_t PosInclude = Guard.rfind("include/");
29   if (PosInclude != StringRef::npos)
30     Guard = Guard.substr(PosInclude + std::strlen("include/"));
31 
32   // For clang we drop the _TOOLS_.
33   size_t PosToolsClang = Guard.rfind("tools/clang/");
34   if (PosToolsClang != StringRef::npos)
35     Guard = Guard.substr(PosToolsClang + std::strlen("tools/"));
36 
37   // Unlike LLVM svn, LLVM git monorepo is named llvm-project, so we replace
38   // "/llvm-project/" with the cannonical "/llvm/".
39   const static StringRef LLVMProject = "/llvm-project/";
40   size_t PosLLVMProject = Guard.rfind(std::string(LLVMProject));
41   if (PosLLVMProject != StringRef::npos)
42     Guard = Guard.replace(PosLLVMProject, LLVMProject.size(), "/llvm/");
43 
44   // The remainder is LLVM_FULL_PATH_TO_HEADER_H
45   size_t PosLLVM = Guard.rfind("llvm/");
46   if (PosLLVM != StringRef::npos)
47     Guard = Guard.substr(PosLLVM);
48 
49   std::replace(Guard.begin(), Guard.end(), '/', '_');
50   std::replace(Guard.begin(), Guard.end(), '.', '_');
51   std::replace(Guard.begin(), Guard.end(), '-', '_');
52 
53   // The prevalent style in clang is LLVM_CLANG_FOO_BAR_H
54   if (StringRef(Guard).startswith("clang"))
55     Guard = "LLVM_" + Guard;
56 
57   // The prevalent style in flang is FORTRAN_FOO_BAR_H
58   if (StringRef(Guard).startswith("flang"))
59     Guard = "FORTRAN" + Guard.substr(sizeof("flang") - 1);
60 
61   return StringRef(Guard).upper();
62 }
63 
64 } // namespace llvm_check
65 } // namespace tidy
66 } // namespace clang
67