COFFImportFile.h revision d111c7844ec26448764ced627e153f406d730c5f
1//===- COFFImportFile.h - COFF short import file implementation -*- 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// COFF short import file is a special kind of file which contains
10// only symbol names for DLL-exported symbols. This class implements
11// exporting of Symbols to create libraries and a SymbolicFile
12// interface for the file type.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_OBJECT_COFF_IMPORT_FILE_H
17#define LLVM_OBJECT_COFF_IMPORT_FILE_H
18
19#include "llvm/ADT/ArrayRef.h"
20#include "llvm/Object/COFF.h"
21#include "llvm/Object/IRObjectFile.h"
22#include "llvm/Object/ObjectFile.h"
23#include "llvm/Object/SymbolicFile.h"
24#include "llvm/Support/MemoryBuffer.h"
25#include "llvm/Support/raw_ostream.h"
26
27namespace llvm {
28namespace object {
29
30class COFFImportFile : public SymbolicFile {
31public:
32  COFFImportFile(MemoryBufferRef Source)
33      : SymbolicFile(ID_COFFImportFile, Source) {}
34
35  static bool classof(Binary const *V) { return V->isCOFFImportFile(); }
36
37  void moveSymbolNext(DataRefImpl &Symb) const override { ++Symb.p; }
38
39  Error printSymbolName(raw_ostream &OS, DataRefImpl Symb) const override {
40    if (Symb.p == 0)
41      OS << "__imp_";
42    OS << StringRef(Data.getBufferStart() + sizeof(coff_import_header));
43    return Error::success();
44  }
45
46  uint32_t getSymbolFlags(DataRefImpl Symb) const override {
47    return SymbolRef::SF_Global;
48  }
49
50  basic_symbol_iterator symbol_begin() const override {
51    return BasicSymbolRef(DataRefImpl(), this);
52  }
53
54  basic_symbol_iterator symbol_end() const override {
55    DataRefImpl Symb;
56    Symb.p = isData() ? 1 : 2;
57    return BasicSymbolRef(Symb, this);
58  }
59
60  const coff_import_header *getCOFFImportHeader() const {
61    return reinterpret_cast<const object::coff_import_header *>(
62        Data.getBufferStart());
63  }
64
65private:
66  bool isData() const {
67    return getCOFFImportHeader()->getType() == COFF::IMPORT_DATA;
68  }
69};
70
71struct COFFShortExport {
72  /// The name of the export as specified in the .def file or on the command
73  /// line, i.e. "foo" in "/EXPORT:foo", and "bar" in "/EXPORT:foo=bar". This
74  /// may lack mangling, such as underscore prefixing and stdcall suffixing.
75  std::string Name;
76
77  /// The external, exported name. Only non-empty when export renaming is in
78  /// effect, i.e. "foo" in "/EXPORT:foo=bar".
79  std::string ExtName;
80
81  /// The real, mangled symbol name from the object file. Given
82  /// "/export:foo=bar", this could be "_bar@8" if bar is stdcall.
83  std::string SymbolName;
84
85  /// Creates a weak alias. This is the name of the weak aliasee. In a .def
86  /// file, this is "baz" in "EXPORTS\nfoo = bar == baz".
87  std::string AliasTarget;
88
89  uint16_t Ordinal = 0;
90  bool Noname = false;
91  bool Data = false;
92  bool Private = false;
93  bool Constant = false;
94
95  friend bool operator==(const COFFShortExport &L, const COFFShortExport &R) {
96    return L.Name == R.Name && L.ExtName == R.ExtName &&
97            L.Ordinal == R.Ordinal && L.Noname == R.Noname &&
98            L.Data == R.Data && L.Private == R.Private;
99  }
100
101  friend bool operator!=(const COFFShortExport &L, const COFFShortExport &R) {
102    return !(L == R);
103  }
104};
105
106Error writeImportLibrary(StringRef ImportName, StringRef Path,
107                         ArrayRef<COFFShortExport> Exports,
108                         COFF::MachineTypes Machine, bool MinGW);
109
110} // namespace object
111} // namespace llvm
112
113#endif
114