clang/lib/StaticAnalyzer/Checkers/Yaml.h

   1 //== Yaml.h ---------------------------------------------------- -*- C++ -*--=//
   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 // This file defines convenience functions for handling YAML configuration files
  10 // for checkers/packages.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_CLANG_LIB_STATICANALYZER_CHECKER_YAML_H
  15 #define LLVM_CLANG_LIB_STATICANALYZER_CHECKER_YAML_H
  16
  17 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
  18 #include "llvm/Support/VirtualFileSystem.h"
  19 #include "llvm/Support/YAMLTraits.h"
  20 #include <optional>
  21
  22 namespace clang {
  23 namespace ento {
  24
  25 /// Read the given file from the filesystem and parse it as a yaml file. The
  26 /// template parameter must have a yaml MappingTraits.
  27 /// Emit diagnostic error in case of any failure.
  28 template <class T, class Checker>
  29 std::optional<T> getConfiguration(CheckerManager &Mgr, Checker *Chk,
  30                                   StringRef Option, StringRef ConfigFile) {
  31   if (ConfigFile.trim().empty())
  32     return std::nullopt;
  33
  34   llvm::vfs::FileSystem *FS = llvm::vfs::getRealFileSystem().get();
  35   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Buffer =
  36       FS->getBufferForFile(ConfigFile.str());
  37
  38   if (Buffer.getError()) {
  39     Mgr.reportInvalidCheckerOptionValue(Chk, Option,
  40                                         "a valid filename instead of '" +
  41                                             std::string(ConfigFile) + "'");
  42     return std::nullopt;
  43   }
  44
  45   llvm::yaml::Input Input(Buffer.get()->getBuffer());
  46   T Config;
  47   Input >> Config;
  48
  49   if (std::error_code ec = Input.error()) {
  50     Mgr.reportInvalidCheckerOptionValue(Chk, Option,
  51                                         "a valid yaml file: " + ec.message());
  52     return std::nullopt;
  53   }
  54
  55   return Config;
  56 }
  57
  58 } // namespace ento
  59 } // namespace clang
  60
  61 #endif // LLVM_CLANG_LIB_STATICANALYZER_CHECKER_YAML_H