1//===- yaml2obj - Convert YAML to a binary object file --------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This program takes a YAML description of an object file and outputs the
11// binary equivalent.
12//
13// This is used for writing tests that require binary files.
14//
15//===----------------------------------------------------------------------===//
16
17#include "yaml2obj.h"
18#include "llvm/ADT/StringExtras.h"
19#include "llvm/Support/CommandLine.h"
20#include "llvm/Support/FileSystem.h"
21#include "llvm/Support/ManagedStatic.h"
22#include "llvm/Support/MemoryBuffer.h"
23#include "llvm/Support/PrettyStackTrace.h"
24#include "llvm/Support/Signals.h"
25#include "llvm/Support/ToolOutputFile.h"
26#include "llvm/Support/YAMLTraits.h"
27#include "llvm/Support/raw_ostream.h"
28#include <system_error>
29
30using namespace llvm;
31
32static cl::opt<std::string>
33  Input(cl::Positional, cl::desc("<input>"), cl::init("-"));
34
35// TODO: The "right" way to tell what kind of object file a given YAML file
36// corresponds to is to look at YAML "tags" (e.g. `!Foo`). Then, different
37// tags (`!ELF`, `!COFF`, etc.) would be used to discriminate between them.
38// Interpreting the tags is needed eventually for when writing test cases,
39// so that we can e.g. have `!Archive` contain a sequence of `!ELF`, and
40// just Do The Right Thing. However, interpreting these tags and acting on
41// them appropriately requires some work in the YAML parser and the YAMLIO
42// library.
43enum YAMLObjectFormat {
44  YOF_COFF,
45  YOF_ELF
46};
47
48cl::opt<YAMLObjectFormat> Format(
49  "format",
50  cl::desc("Interpret input as this type of object file"),
51  cl::values(
52    clEnumValN(YOF_COFF, "coff", "COFF object file format"),
53    clEnumValN(YOF_ELF, "elf", "ELF object file format"),
54  clEnumValEnd));
55
56cl::opt<unsigned>
57DocNum("docnum", cl::init(1),
58       cl::desc("Read specified document from input (default = 1)"));
59
60static cl::opt<std::string> OutputFilename("o", cl::desc("Output filename"),
61                                           cl::value_desc("filename"));
62
63typedef int (*ConvertFuncPtr)(yaml::Input & YIn, raw_ostream &Out);
64
65int convertYAML(yaml::Input & YIn, raw_ostream &Out, ConvertFuncPtr Convert) {
66  unsigned CurDocNum = 0;
67  do {
68    if (++CurDocNum == DocNum)
69      return Convert(YIn, Out);
70  } while (YIn.nextDocument());
71
72  errs() << "yaml2obj: Cannot find the " << DocNum
73         << llvm::getOrdinalSuffix(DocNum) << " document\n";
74  return 1;
75}
76
77int main(int argc, char **argv) {
78  cl::ParseCommandLineOptions(argc, argv);
79  sys::PrintStackTraceOnErrorSignal();
80  PrettyStackTraceProgram X(argc, argv);
81  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
82
83  if (OutputFilename.empty())
84    OutputFilename = "-";
85
86  std::string ErrorInfo;
87  std::unique_ptr<tool_output_file> Out(
88      new tool_output_file(OutputFilename.c_str(), ErrorInfo, sys::fs::F_None));
89  if (!ErrorInfo.empty()) {
90    errs() << ErrorInfo << '\n';
91    return 1;
92  }
93
94  ErrorOr<std::unique_ptr<MemoryBuffer>> Buf =
95      MemoryBuffer::getFileOrSTDIN(Input);
96  if (!Buf)
97    return 1;
98
99  ConvertFuncPtr Convert = nullptr;
100  if (Format == YOF_COFF)
101    Convert = yaml2coff;
102  else if (Format == YOF_ELF)
103    Convert = yaml2elf;
104  else {
105    errs() << "Not yet implemented\n";
106    return 1;
107  }
108
109  yaml::Input YIn(Buf.get()->getBuffer());
110
111  int Res = convertYAML(YIn, Out->os(), Convert);
112  if (Res == 0)
113    Out->keep();
114
115  return Res;
116}
117