llvm-readobj.cpp revision d326d05fb9c794e93fc7fc0601028f196600f7e2 
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 "llvm/ADT/Triple.h"
25#include "llvm/Analysis/Verifier.h"
26#include "llvm/Object/ELF.h"
27#include "llvm/Object/ObjectFile.h"
28#include "llvm/Support/CommandLine.h"
29#include "llvm/Support/Debug.h"
30#include "llvm/Support/Format.h"
31#include "llvm/Support/FormattedStream.h"
32#include "llvm/Support/PrettyStackTrace.h"
33#include "llvm/Support/Signals.h"
34
35using namespace llvm;
36using namespace llvm::object;
37
38static cl::opt<std::string>
39InputFilename(cl::Positional, cl::desc("<input object>"), cl::init(""));
40
41static void dumpSymbolHeader() {
42  outs() << format("  %-32s", (const char*)"Name")
43         << format("  %-4s", (const char*)"Type")
44         << format("  %-16s", (const char*)"Address")
45         << format("  %-16s", (const char*)"Size")
46         << format("  %-16s", (const char*)"FileOffset")
47         << format("  %-26s", (const char*)"Flags")
48         << "\n";
49}
50
51static void dumpSectionHeader() {
52  outs() << format("  %-24s", (const char*)"Name")
53         << format("  %-16s", (const char*)"Address")
54         << format("  %-16s", (const char*)"Size")
55         << format("  %-8s", (const char*)"Align")
56         << format("  %-26s", (const char*)"Flags")
57         << "\n";
58}
59
60static const char *getTypeStr(SymbolRef::Type Type) {
61  switch (Type) {
62  case SymbolRef::ST_Unknown: return "?";
63  case SymbolRef::ST_Data: return "DATA";
64  case SymbolRef::ST_Debug: return "DBG";
65  case SymbolRef::ST_File: return "FILE";
66  case SymbolRef::ST_Function: return "FUNC";
67  case SymbolRef::ST_Other: return "-";
68  }
69  return "INV";
70}
71
72static std::string getSymbolFlagStr(uint32_t Flags) {
73  std::string result;
74  if (Flags & SymbolRef::SF_Undefined)
75    result += "undef,";
76  if (Flags & SymbolRef::SF_Global)
77    result += "global,";
78  if (Flags & SymbolRef::SF_Weak)
79    result += "weak,";
80  if (Flags & SymbolRef::SF_Absolute)
81    result += "absolute,";
82  if (Flags & SymbolRef::SF_ThreadLocal)
83    result += "threadlocal,";
84  if (Flags & SymbolRef::SF_Common)
85    result += "common,";
86  if (Flags & SymbolRef::SF_FormatSpecific)
87    result += "formatspecific,";
88
89  // Remove trailing comma
90  if (result.size() > 0) {
91    result.erase(result.size() - 1);
92  }
93  return result;
94}
95
96static void checkError(error_code ec, const char *msg) {
97  if (ec)
98    report_fatal_error(std::string(msg) + ": " + ec.message());
99}
100
101static std::string getSectionFlagStr(const SectionRef &Section) {
102  const struct {
103    error_code (SectionRef::*MemF)(bool &) const;
104    const char *FlagStr, *ErrorStr;
105  } Work[] =
106      {{ &SectionRef::isText, "text,", "Section.isText() failed" },
107       { &SectionRef::isData, "data,", "Section.isData() failed" },
108       { &SectionRef::isBSS, "bss,", "Section.isBSS() failed"  },
109       { &SectionRef::isRequiredForExecution, "required,",
110         "Section.isRequiredForExecution() failed" },
111       { &SectionRef::isVirtual, "virtual,", "Section.isVirtual() failed" },
112       { &SectionRef::isZeroInit, "zeroinit,", "Section.isZeroInit() failed" },
113       { &SectionRef::isReadOnlyData, "rodata,",
114         "Section.isReadOnlyData() failed" }};
115
116  std::string result;
117  for (uint32_t I = 0; I < sizeof(Work)/sizeof(*Work); ++I) {
118    bool B;
119    checkError((Section.*Work[I].MemF)(B), Work[I].ErrorStr);
120    if (B)
121      result += Work[I].FlagStr;
122  }
123
124  // Remove trailing comma
125  if (result.size() > 0) {
126    result.erase(result.size() - 1);
127  }
128  return result;
129}
130
131static void
132dumpSymbol(const SymbolRef &Sym, const ObjectFile *obj, bool IsDynamic) {
133  StringRef Name;
134  SymbolRef::Type Type;
135  uint32_t Flags;
136  uint64_t Address;
137  uint64_t Size;
138  uint64_t FileOffset;
139  checkError(Sym.getName(Name), "SymbolRef.getName() failed");
140  checkError(Sym.getAddress(Address), "SymbolRef.getAddress() failed");
141  checkError(Sym.getSize(Size), "SymbolRef.getSize() failed");
142  checkError(Sym.getFileOffset(FileOffset),
143             "SymbolRef.getFileOffset() failed");
144  checkError(Sym.getType(Type), "SymbolRef.getType() failed");
145  checkError(Sym.getFlags(Flags), "SymbolRef.getFlags() failed");
146  std::string FullName = Name;
147
148  // If this is a dynamic symbol from an ELF object, append
149  // the symbol's version to the name.
150  if (IsDynamic && obj->isELF()) {
151    StringRef Version;
152    bool IsDefault;
153    GetELFSymbolVersion(obj, Sym, Version, IsDefault);
154    if (!Version.empty()) {
155      FullName += (IsDefault ? "@@" : "@");
156      FullName += Version;
157    }
158  }
159
160  // format() can't handle StringRefs
161  outs() << format("  %-32s", FullName.c_str())
162         << format("  %-4s", getTypeStr(Type))
163         << format("  %16" PRIx64, Address)
164         << format("  %16" PRIx64, Size)
165         << format("  %16" PRIx64, FileOffset)
166         << "  " << getSymbolFlagStr(Flags)
167         << "\n";
168}
169
170static void dumpStaticSymbol(const SymbolRef &Sym, const ObjectFile *obj) {
171  return dumpSymbol(Sym, obj, false);
172}
173
174static void dumpDynamicSymbol(const SymbolRef &Sym, const ObjectFile *obj) {
175  return dumpSymbol(Sym, obj, true);
176}
177
178static void dumpSection(const SectionRef &Section, const ObjectFile *obj) {
179  StringRef Name;
180  checkError(Section.getName(Name), "SectionRef::getName() failed");
181  uint64_t Addr, Size, Align;
182  checkError(Section.getAddress(Addr), "SectionRef::getAddress() failed");
183  checkError(Section.getSize(Size), "SectionRef::getSize() failed");
184  checkError(Section.getAlignment(Align), "SectionRef::getAlignment() failed");
185  outs() << format("  %-24s", std::string(Name).c_str())
186         << format("  %16" PRIx64, Addr)
187         << format("  %16" PRIx64, Size)
188         << format("  %8" PRIx64, Align)
189         << "  " << getSectionFlagStr(Section)
190         << "\n";
191}
192
193static void dumpLibrary(const LibraryRef &lib, const ObjectFile *obj) {
194  StringRef path;
195  lib.getPath(path);
196  outs() << "  " << path << "\n";
197}
198
199template<typename Iterator, typename Func>
200static void dump(const ObjectFile *obj, Func f, Iterator begin, Iterator end,
201                 const char *errStr) {
202  error_code ec;
203  uint32_t count = 0;
204  Iterator it = begin, ie = end;
205  while (it != ie) {
206    f(*it, obj);
207    it.increment(ec);
208    if (ec)
209      report_fatal_error(errStr);
210    ++count;
211  }
212  outs() << "  Total: " << count << "\n\n";
213}
214
215static void dumpHeaders(const ObjectFile *obj) {
216  outs() << "File Format : " << obj->getFileFormatName() << "\n";
217  outs() << "Arch        : "
218         << Triple::getArchTypeName((llvm::Triple::ArchType)obj->getArch())
219         << "\n";
220  outs() << "Address Size: " << (8*obj->getBytesInAddress()) << " bits\n";
221  outs() << "Load Name   : " << obj->getLoadName() << "\n";
222  outs() << "\n";
223}
224
225int main(int argc, char** argv) {
226  error_code ec;
227  sys::PrintStackTraceOnErrorSignal();
228  PrettyStackTraceProgram X(argc, argv);
229
230  cl::ParseCommandLineOptions(argc, argv,
231                              "LLVM Object Reader\n");
232
233  if (InputFilename.empty()) {
234    errs() << "Please specify an input filename\n";
235    return 1;
236  }
237
238  // Open the object file
239  OwningPtr<MemoryBuffer> File;
240  if (MemoryBuffer::getFile(InputFilename, File)) {
241    errs() << InputFilename << ": Open failed\n";
242    return 1;
243  }
244
245  OwningPtr<ObjectFile> o(ObjectFile::createObjectFile(File.take()));
246  ObjectFile *obj = o.get();
247  if (!obj) {
248    errs() << InputFilename << ": Object type not recognized\n";
249  }
250
251  dumpHeaders(obj);
252
253  outs() << "Symbols:\n";
254  dumpSymbolHeader();
255  dump(obj, dumpStaticSymbol, obj->begin_symbols(), obj->end_symbols(),
256       "Symbol iteration failed");
257
258  outs() << "Dynamic Symbols:\n";
259  dumpSymbolHeader();
260  dump(obj, dumpDynamicSymbol, obj->begin_dynamic_symbols(),
261       obj->end_dynamic_symbols(), "Symbol iteration failed");
262
263  outs() << "Sections:\n";
264  dumpSectionHeader();
265  dump(obj, &dumpSection, obj->begin_sections(), obj->end_sections(),
266       "Section iteration failed");
267
268  if (obj->isELF()) {
269    if (ErrorOr<void> e = dumpELFDynamicTable(obj, outs()))
270      ;
271    else
272      errs() << "InputFilename" << ": " << error_code(e).message() << "\n";
273  }
274
275  outs() << "Libraries needed:\n";
276  dump(obj, &dumpLibrary, obj->begin_libraries_needed(),
277       obj->end_libraries_needed(), "Needed libraries iteration failed");
278
279  return 0;
280}
281
282