include/llvm/Object/Error.h

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