llvm-readobj.cpp revision cd81d94322a39503e4a3e87b6ee03d4fcb3465fb 
1//===- llvm-readobj.cpp - Dump contents of an 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 is a tool similar to readelf, except it works on multiple object file
11// formats. The main purpose of this tool is to provide detailed output suitable
12// for FileCheck.
13//
14// Flags should be similar to readelf where supported, but the output format
15// does not need to be identical. The point is to not make users learn yet
16// another set of flags.
17//
18// Output should be specialized for each format where appropriate.
19//
20//===----------------------------------------------------------------------===//
21
22#include "llvm-readobj.h"
23#include "Error.h"
24#include "ObjDumper.h"
25#include "StreamWriter.h"
26#include "llvm/Object/Archive.h"
27#include "llvm/Object/ObjectFile.h"
28#include "llvm/Support/Casting.h"
29#include "llvm/Support/CommandLine.h"
30#include "llvm/Support/DataTypes.h"
31#include "llvm/Support/Debug.h"
32#include "llvm/Support/FileSystem.h"
33#include "llvm/Support/ManagedStatic.h"
34#include "llvm/Support/PrettyStackTrace.h"
35#include "llvm/Support/Signals.h"
36#include "llvm/Support/TargetRegistry.h"
37#include "llvm/Support/TargetSelect.h"
38#include <string>
39#include <system_error>
40
41
42using namespace llvm;
43using namespace llvm::object;
44
45namespace opts {
46  cl::list<std::string> InputFilenames(cl::Positional,
47    cl::desc("<input object files>"),
48    cl::ZeroOrMore);
49
50  // -file-headers, -h
51  cl::opt<bool> FileHeaders("file-headers",
52    cl::desc("Display file headers "));
53  cl::alias FileHeadersShort("h",
54    cl::desc("Alias for --file-headers"),
55    cl::aliasopt(FileHeaders));
56
57  // -sections, -s
58  cl::opt<bool> Sections("sections",
59    cl::desc("Display all sections."));
60  cl::alias SectionsShort("s",
61    cl::desc("Alias for --sections"),
62    cl::aliasopt(Sections));
63
64  // -section-relocations, -sr
65  cl::opt<bool> SectionRelocations("section-relocations",
66    cl::desc("Display relocations for each section shown."));
67  cl::alias SectionRelocationsShort("sr",
68    cl::desc("Alias for --section-relocations"),
69    cl::aliasopt(SectionRelocations));
70
71  // -section-symbols, -st
72  cl::opt<bool> SectionSymbols("section-symbols",
73    cl::desc("Display symbols for each section shown."));
74  cl::alias SectionSymbolsShort("st",
75    cl::desc("Alias for --section-symbols"),
76    cl::aliasopt(SectionSymbols));
77
78  // -section-data, -sd
79  cl::opt<bool> SectionData("section-data",
80    cl::desc("Display section data for each section shown."));
81  cl::alias SectionDataShort("sd",
82    cl::desc("Alias for --section-data"),
83    cl::aliasopt(SectionData));
84
85  // -relocations, -r
86  cl::opt<bool> Relocations("relocations",
87    cl::desc("Display the relocation entries in the file"));
88  cl::alias RelocationsShort("r",
89    cl::desc("Alias for --relocations"),
90    cl::aliasopt(Relocations));
91
92  // -symbols, -t
93  cl::opt<bool> Symbols("symbols",
94    cl::desc("Display the symbol table"));
95  cl::alias SymbolsShort("t",
96    cl::desc("Alias for --symbols"),
97    cl::aliasopt(Symbols));
98
99  // -dyn-symbols, -dt
100  cl::opt<bool> DynamicSymbols("dyn-symbols",
101    cl::desc("Display the dynamic symbol table"));
102  cl::alias DynamicSymbolsShort("dt",
103    cl::desc("Alias for --dyn-symbols"),
104    cl::aliasopt(DynamicSymbols));
105
106  // -unwind, -u
107  cl::opt<bool> UnwindInfo("unwind",
108    cl::desc("Display unwind information"));
109  cl::alias UnwindInfoShort("u",
110    cl::desc("Alias for --unwind"),
111    cl::aliasopt(UnwindInfo));
112
113  // -dynamic-table
114  cl::opt<bool> DynamicTable("dynamic-table",
115    cl::desc("Display the ELF .dynamic section table"));
116
117  // -needed-libs
118  cl::opt<bool> NeededLibraries("needed-libs",
119    cl::desc("Display the needed libraries"));
120
121  // -program-headers
122  cl::opt<bool> ProgramHeaders("program-headers",
123    cl::desc("Display ELF program headers"));
124
125  // -expand-relocs
126  cl::opt<bool> ExpandRelocs("expand-relocs",
127    cl::desc("Expand each shown relocation to multiple lines"));
128
129  // -codeview-linetables
130  cl::opt<bool> CodeViewLineTables("codeview-linetables",
131    cl::desc("Display CodeView line table information"));
132
133  // -arm-attributes, -a
134  cl::opt<bool> ARMAttributes("arm-attributes",
135                              cl::desc("Display the ARM attributes section"));
136  cl::alias ARMAttributesShort("-a", cl::desc("Alias for --arm-attributes"),
137                               cl::aliasopt(ARMAttributes));
138
139  // -mips-plt-got
140  cl::opt<bool>
141  MipsPLTGOT("mips-plt-got",
142             cl::desc("Display the MIPS GOT and PLT GOT sections"));
143} // namespace opts
144
145static int ReturnValue = EXIT_SUCCESS;
146
147namespace llvm {
148
149bool error(std::error_code EC) {
150  if (!EC)
151    return false;
152
153  ReturnValue = EXIT_FAILURE;
154  outs() << "\nError reading file: " << EC.message() << ".\n";
155  outs().flush();
156  return true;
157}
158
159bool relocAddressLess(RelocationRef a, RelocationRef b) {
160  uint64_t a_addr, b_addr;
161  if (error(a.getOffset(a_addr))) return false;
162  if (error(b.getOffset(b_addr))) return false;
163  return a_addr < b_addr;
164}
165
166} // namespace llvm
167
168static void reportError(StringRef Input, std::error_code EC) {
169  if (Input == "-")
170    Input = "<stdin>";
171
172  errs() << Input << ": " << EC.message() << "\n";
173  errs().flush();
174  ReturnValue = EXIT_FAILURE;
175}
176
177static void reportError(StringRef Input, StringRef Message) {
178  if (Input == "-")
179    Input = "<stdin>";
180
181  errs() << Input << ": " << Message << "\n";
182  ReturnValue = EXIT_FAILURE;
183}
184
185static bool isMipsArch(unsigned Arch) {
186  switch (Arch) {
187  case llvm::Triple::mips:
188  case llvm::Triple::mipsel:
189  case llvm::Triple::mips64:
190  case llvm::Triple::mips64el:
191    return true;
192  default:
193    return false;
194  }
195}
196
197/// @brief Creates an format-specific object file dumper.
198static std::error_code createDumper(const ObjectFile *Obj, StreamWriter &Writer,
199                                    std::unique_ptr<ObjDumper> &Result) {
200  if (!Obj)
201    return readobj_error::unsupported_file_format;
202
203  if (Obj->isCOFF())
204    return createCOFFDumper(Obj, Writer, Result);
205  if (Obj->isELF())
206    return createELFDumper(Obj, Writer, Result);
207  if (Obj->isMachO())
208    return createMachODumper(Obj, Writer, Result);
209
210  return readobj_error::unsupported_obj_file_format;
211}
212
213
214/// @brief Dumps the specified object file.
215static void dumpObject(const ObjectFile *Obj) {
216  StreamWriter Writer(outs());
217  std::unique_ptr<ObjDumper> Dumper;
218  if (std::error_code EC = createDumper(Obj, Writer, Dumper)) {
219    reportError(Obj->getFileName(), EC);
220    return;
221  }
222
223  outs() << '\n';
224  outs() << "File: " << Obj->getFileName() << "\n";
225  outs() << "Format: " << Obj->getFileFormatName() << "\n";
226  outs() << "Arch: "
227         << Triple::getArchTypeName((llvm::Triple::ArchType)Obj->getArch())
228         << "\n";
229  outs() << "AddressSize: " << (8*Obj->getBytesInAddress()) << "bit\n";
230  if (Obj->isELF())
231    outs() << "LoadName: " << Obj->getLoadName() << "\n";
232
233  if (opts::FileHeaders)
234    Dumper->printFileHeaders();
235  if (opts::Sections)
236    Dumper->printSections();
237  if (opts::Relocations)
238    Dumper->printRelocations();
239  if (opts::Symbols)
240    Dumper->printSymbols();
241  if (opts::DynamicSymbols)
242    Dumper->printDynamicSymbols();
243  if (opts::UnwindInfo)
244    Dumper->printUnwindInfo();
245  if (opts::DynamicTable)
246    Dumper->printDynamicTable();
247  if (opts::NeededLibraries)
248    Dumper->printNeededLibraries();
249  if (opts::ProgramHeaders)
250    Dumper->printProgramHeaders();
251  if (Obj->getArch() == llvm::Triple::arm && Obj->isELF())
252    if (opts::ARMAttributes)
253      Dumper->printAttributes();
254  if (isMipsArch(Obj->getArch()) && Obj->isELF())
255    if (opts::MipsPLTGOT)
256      Dumper->printMipsPLTGOT();
257}
258
259
260/// @brief Dumps each object file in \a Arc;
261static void dumpArchive(const Archive *Arc) {
262  for (Archive::child_iterator ArcI = Arc->child_begin(),
263                               ArcE = Arc->child_end();
264                               ArcI != ArcE; ++ArcI) {
265    ErrorOr<std::unique_ptr<Binary>> ChildOrErr = ArcI->getAsBinary();
266    if (std::error_code EC = ChildOrErr.getError()) {
267      // Ignore non-object files.
268      if (EC != object_error::invalid_file_type)
269        reportError(Arc->getFileName(), EC.message());
270      continue;
271    }
272
273    if (ObjectFile *Obj = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
274      dumpObject(Obj);
275    else
276      reportError(Arc->getFileName(), readobj_error::unrecognized_file_format);
277  }
278}
279
280
281/// @brief Opens \a File and dumps it.
282static void dumpInput(StringRef File) {
283  // If file isn't stdin, check that it exists.
284  if (File != "-" && !sys::fs::exists(File)) {
285    reportError(File, readobj_error::file_not_found);
286    return;
287  }
288
289  // Attempt to open the binary.
290  ErrorOr<Binary *> BinaryOrErr = createBinary(File);
291  if (std::error_code EC = BinaryOrErr.getError()) {
292    reportError(File, EC);
293    return;
294  }
295  std::unique_ptr<Binary> Binary(BinaryOrErr.get());
296
297  if (Archive *Arc = dyn_cast<Archive>(Binary.get()))
298    dumpArchive(Arc);
299  else if (ObjectFile *Obj = dyn_cast<ObjectFile>(Binary.get()))
300    dumpObject(Obj);
301  else
302    reportError(File, readobj_error::unrecognized_file_format);
303}
304
305
306int main(int argc, const char *argv[]) {
307  sys::PrintStackTraceOnErrorSignal();
308  PrettyStackTraceProgram X(argc, argv);
309  llvm_shutdown_obj Y;
310
311  // Initialize targets.
312  llvm::InitializeAllTargetInfos();
313
314  // Register the target printer for --version.
315  cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
316
317  cl::ParseCommandLineOptions(argc, argv, "LLVM Object Reader\n");
318
319  // Default to stdin if no filename is specified.
320  if (opts::InputFilenames.size() == 0)
321    opts::InputFilenames.push_back("-");
322
323  std::for_each(opts::InputFilenames.begin(), opts::InputFilenames.end(),
324                dumpInput);
325
326  return ReturnValue;
327}
328