1 //===- Error.h - system_error extensions for Object -------------*- 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 declares a new error_category for the Object library.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_OBJECT_ERROR_H
14 #define LLVM_OBJECT_ERROR_H
15 
16 #include "llvm/Support/Error.h"
17 #include <system_error>
18 
19 namespace llvm {
20 
21 class Twine;
22 
23 namespace object {
24 
25 class Binary;
26 
27 const std::error_category &object_category();
28 
29 enum class object_error {
30   // Error code 0 is absent. Use std::error_code() instead.
31   arch_not_found = 1,
32   invalid_file_type,
33   parse_failed,
34   unexpected_eof,
35   string_table_non_null_end,
36   invalid_section_index,
37   bitcode_section_not_found,
38   invalid_symbol_index,
39 };
40 
41 inline std::error_code make_error_code(object_error e) {
42   return std::error_code(static_cast<int>(e), object_category());
43 }
44 
45 /// Base class for all errors indicating malformed binary files.
46 ///
47 /// Having a subclass for all malformed binary files allows archive-walking
48 /// code to skip malformed files without having to understand every possible
49 /// way that a binary file might be malformed.
50 ///
51 /// Currently inherits from ECError for easy interoperability with
52 /// std::error_code, but this will be removed in the future.
53 class BinaryError : public ErrorInfo<BinaryError, ECError> {
54   void anchor() override;
55 public:
56   static char ID;
57   BinaryError() {
58     // Default to parse_failed, can be overridden with setErrorCode.
59     setErrorCode(make_error_code(object_error::parse_failed));
60   }
61 };
62 
63 /// Generic binary error.
64 ///
65 /// For errors that don't require their own specific sub-error (most errors)
66 /// this class can be used to describe the error via a string message.
67 class GenericBinaryError : public ErrorInfo<GenericBinaryError, BinaryError> {
68 public:
69   static char ID;
70   GenericBinaryError(const Twine &Msg);
71   GenericBinaryError(const Twine &Msg, object_error ECOverride);
72   const std::string &getMessage() const { return Msg; }
73   void log(raw_ostream &OS) const override;
74 private:
75   std::string Msg;
76 };
77 
78 /// isNotObjectErrorInvalidFileType() is used when looping through the children
79 /// of an archive after calling getAsBinary() on the child and it returns an
80 /// llvm::Error.  In the cases we want to loop through the children and ignore the
81 /// non-objects in the archive this is used to test the error to see if an
82 /// error() function needs to called on the llvm::Error.
83 Error isNotObjectErrorInvalidFileType(llvm::Error Err);
84 
85 } // end namespace object.
86 
87 } // end namespace llvm.
88 
89 namespace std {
90 template <>
91 struct is_error_code_enum<llvm::object::object_error> : std::true_type {};
92 }
93 
94 #endif
95