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 (std::error_code ec = 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
62