llvm-readobj.cpp revision 956ca7265c697107708468b7e1b2fd21f4185bae 
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
24#include "Error.h"
25#include "ObjDumper.h"
26#include "StreamWriter.h"
27
28#include "llvm/Object/Archive.h"
29#include "llvm/Object/ObjectFile.h"
30#include "llvm/Support/Casting.h"
31#include "llvm/Support/CommandLine.h"
32#include "llvm/Support/DataTypes.h"
33#include "llvm/Support/Debug.h"
34#include "llvm/Support/FileSystem.h"
35#include "llvm/Support/ManagedStatic.h"
36#include "llvm/Support/PrettyStackTrace.h"
37#include "llvm/Support/Signals.h"
38#include "llvm/Support/TargetRegistry.h"
39#include "llvm/Support/TargetSelect.h"
40#include "llvm/Support/system_error.h"
41
42#include <string>
43
44
45using namespace llvm;
46using namespace llvm::object;
47
48namespace opts {
49  cl::list<std::string> InputFilenames(cl::Positional,
50    cl::desc("<input object files>"),
51    cl::ZeroOrMore);
52
53  // -file-headers, -h
54  cl::opt<bool> FileHeaders("file-headers",
55    cl::desc("Display file headers "));
56  cl::alias FileHeadersShort("h",
57    cl::desc("Alias for --file-headers"),
58    cl::aliasopt(FileHeaders));
59
60  // -sections, -s
61  cl::opt<bool> Sections("sections",
62    cl::desc("Display all sections."));
63  cl::alias SectionsShort("s",
64    cl::desc("Alias for --sections"),
65    cl::aliasopt(Sections));
66
67  // -section-relocations, -sr
68  cl::opt<bool> SectionRelocations("section-relocations",
69    cl::desc("Display relocations for each section shown."));
70  cl::alias SectionRelocationsShort("sr",
71    cl::desc("Alias for --section-relocations"),
72    cl::aliasopt(SectionRelocations));
73
74  // -section-symbols, -st
75  cl::opt<bool> SectionSymbols("section-symbols",
76    cl::desc("Display symbols for each section shown."));
77  cl::alias SectionSymbolsShort("st",
78    cl::desc("Alias for --section-symbols"),
79    cl::aliasopt(SectionSymbols));
80
81  // -section-data, -sd
82  cl::opt<bool> SectionData("section-data",
83    cl::desc("Display section data for each section shown."));
84  cl::alias SectionDataShort("sd",
85    cl::desc("Alias for --section-data"),
86    cl::aliasopt(SectionData));
87
88  // -relocations, -r
89  cl::opt<bool> Relocations("relocations",
90    cl::desc("Display the relocation entries in the file"));
91  cl::alias RelocationsShort("r",
92    cl::desc("Alias for --relocations"),
93    cl::aliasopt(Relocations));
94
95  // -symbols, -t
96  cl::opt<bool> Symbols("symbols",
97    cl::desc("Display the symbol table"));
98  cl::alias SymbolsShort("t",
99    cl::desc("Alias for --symbols"),
100    cl::aliasopt(Symbols));
101
102  // -dyn-symbols, -dt
103  cl::opt<bool> DynamicSymbols("dyn-symbols",
104    cl::desc("Display the dynamic symbol table"));
105  cl::alias DynamicSymbolsShort("dt",
106    cl::desc("Alias for --dyn-symbols"),
107    cl::aliasopt(DynamicSymbols));
108
109  // -unwind, -u
110  cl::opt<bool> UnwindInfo("unwind",
111    cl::desc("Display unwind information"));
112  cl::alias UnwindInfoShort("u",
113    cl::desc("Alias for --unwind"),
114    cl::aliasopt(UnwindInfo));
115
116  // -dynamic-table
117  cl::opt<bool> DynamicTable("dynamic-table",
118    cl::desc("Display the ELF .dynamic section table"));
119
120  // -needed-libs
121  cl::opt<bool> NeededLibraries("needed-libs",
122    cl::desc("Display the needed libraries"));
123
124  // -program-headers
125  cl::opt<bool> ProgramHeaders("program-headers",
126    cl::desc("Display ELF program headers"));
127
128  // -expand-relocs
129  cl::opt<bool> ExpandRelocs("expand-relocs",
130    cl::desc("Expand each shown relocation to multiple lines"));
131} // namespace opts
132
133namespace llvm {
134
135bool error(error_code EC) {
136  if (!EC)
137    return false;
138
139  outs() << "\nError reading file: " << EC.message() << ".\n";
140  outs().flush();
141  return true;
142}
143
144bool relocAddressLess(RelocationRef a, RelocationRef b) {
145  uint64_t a_addr, b_addr;
146  if (error(a.getOffset(a_addr))) return false;
147  if (error(b.getOffset(b_addr))) return false;
148  return a_addr < b_addr;
149}
150
151} // namespace llvm
152
153
154static void reportError(StringRef Input, error_code EC) {
155  if (Input == "-")
156    Input = "<stdin>";
157
158  errs() << Input << ": " << EC.message() << "\n";
159  errs().flush();
160}
161
162static void reportError(StringRef Input, StringRef Message) {
163  if (Input == "-")
164    Input = "<stdin>";
165
166  errs() << Input << ": " << Message << "\n";
167}
168
169/// @brief Creates an format-specific object file dumper.
170static error_code createDumper(const ObjectFile *Obj,
171                               StreamWriter &Writer,
172                               OwningPtr<ObjDumper> &Result) {
173  if (!Obj)
174    return readobj_error::unsupported_file_format;
175
176  if (Obj->isCOFF())
177    return createCOFFDumper(Obj, Writer, Result);
178  if (Obj->isELF())
179    return createELFDumper(Obj, Writer, Result);
180  if (Obj->isMachO())
181    return createMachODumper(Obj, Writer, Result);
182
183  return readobj_error::unsupported_obj_file_format;
184}
185
186
187/// @brief Dumps the specified object file.
188static void dumpObject(const ObjectFile *Obj) {
189  StreamWriter Writer(outs());
190  OwningPtr<ObjDumper> Dumper;
191  if (error_code EC = createDumper(Obj, Writer, Dumper)) {
192    reportError(Obj->getFileName(), EC);
193    return;
194  }
195
196  outs() << '\n';
197  outs() << "File: " << Obj->getFileName() << "\n";
198  outs() << "Format: " << Obj->getFileFormatName() << "\n";
199  outs() << "Arch: "
200         << Triple::getArchTypeName((llvm::Triple::ArchType)Obj->getArch())
201         << "\n";
202  outs() << "AddressSize: " << (8*Obj->getBytesInAddress()) << "bit\n";
203  if (Obj->isELF())
204    outs() << "LoadName: " << Obj->getLoadName() << "\n";
205
206  if (opts::FileHeaders)
207    Dumper->printFileHeaders();
208  if (opts::Sections)
209    Dumper->printSections();
210  if (opts::Relocations)
211    Dumper->printRelocations();
212  if (opts::Symbols)
213    Dumper->printSymbols();
214  if (opts::DynamicSymbols)
215    Dumper->printDynamicSymbols();
216  if (opts::UnwindInfo)
217    Dumper->printUnwindInfo();
218  if (opts::DynamicTable)
219    Dumper->printDynamicTable();
220  if (opts::NeededLibraries)
221    Dumper->printNeededLibraries();
222  if (opts::ProgramHeaders)
223    Dumper->printProgramHeaders();
224}
225
226
227/// @brief Dumps each object file in \a Arc;
228static void dumpArchive(const Archive *Arc) {
229  for (Archive::child_iterator ArcI = Arc->begin_children(),
230                               ArcE = Arc->end_children();
231                               ArcI != ArcE; ++ArcI) {
232    OwningPtr<Binary> child;
233    if (error_code EC = ArcI->getAsBinary(child)) {
234      // Ignore non-object files.
235      if (EC != object_error::invalid_file_type)
236        reportError(Arc->getFileName(), EC.message());
237      continue;
238    }
239
240    if (ObjectFile *Obj = dyn_cast<ObjectFile>(child.get()))
241      dumpObject(Obj);
242    else
243      reportError(Arc->getFileName(), readobj_error::unrecognized_file_format);
244  }
245}
246
247
248/// @brief Opens \a File and dumps it.
249static void dumpInput(StringRef File) {
250  // If file isn't stdin, check that it exists.
251  if (File != "-" && !sys::fs::exists(File)) {
252    reportError(File, readobj_error::file_not_found);
253    return;
254  }
255
256  // Attempt to open the binary.
257  OwningPtr<Binary> Binary;
258  if (error_code EC = createBinary(File, Binary)) {
259    reportError(File, EC);
260    return;
261  }
262
263  if (Archive *Arc = dyn_cast<Archive>(Binary.get()))
264    dumpArchive(Arc);
265  else if (ObjectFile *Obj = dyn_cast<ObjectFile>(Binary.get()))
266    dumpObject(Obj);
267  else
268    reportError(File, readobj_error::unrecognized_file_format);
269}
270
271
272int main(int argc, const char *argv[]) {
273  sys::PrintStackTraceOnErrorSignal();
274  PrettyStackTraceProgram X(argc, argv);
275  llvm_shutdown_obj Y;
276
277  // Initialize targets.
278  llvm::InitializeAllTargetInfos();
279
280  // Register the target printer for --version.
281  cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
282
283  cl::ParseCommandLineOptions(argc, argv, "LLVM Object Reader\n");
284
285  // Default to stdin if no filename is specified.
286  if (opts::InputFilenames.size() == 0)
287    opts::InputFilenames.push_back("-");
288
289  std::for_each(opts::InputFilenames.begin(), opts::InputFilenames.end(),
290                dumpInput);
291
292  return 0;
293}
294