llvm-readobj.cpp revision bd1737c8460ee09d000492831788ecc17dbc368a 
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("  %-4s", (const char *)"Section")
45         << format("  %-16s", (const char *)"Address")
46         << format("  %-16s", (const char *)"Size")
47         << format("  %-16s", (const char *)"FileOffset")
48         << format("  %-26s", (const char *)"Flags") << "\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  llvm::object::section_iterator symSection(obj->begin_sections());
149  Sym.getSection(symSection);
150  StringRef sectionName;
151
152  if (symSection != obj->end_sections())
153    checkError(symSection->getName(sectionName),
154               "SectionRef::getName() failed");
155
156  // If this is a dynamic symbol from an ELF object, append
157  // the symbol's version to the name.
158  if (IsDynamic && obj->isELF()) {
159    StringRef Version;
160    bool IsDefault;
161    GetELFSymbolVersion(obj, Sym, Version, IsDefault);
162    if (!Version.empty()) {
163      FullName += (IsDefault ? "@@" : "@");
164      FullName += Version;
165    }
166  }
167
168  // format() can't handle StringRefs
169  outs() << format("  %-32s", FullName.c_str())
170         << format("  %-4s", getTypeStr(Type))
171         << format("  %-32s", std::string(sectionName).c_str())
172         << format("  %16" PRIx64, Address) << format("  %16" PRIx64, Size)
173         << format("  %16" PRIx64, FileOffset) << "  "
174         << getSymbolFlagStr(Flags) << "\n";
175}
176
177static void dumpStaticSymbol(const SymbolRef &Sym, const ObjectFile *obj) {
178  return dumpSymbol(Sym, obj, false);
179}
180
181static void dumpDynamicSymbol(const SymbolRef &Sym, const ObjectFile *obj) {
182  return dumpSymbol(Sym, obj, true);
183}
184
185static void dumpSection(const SectionRef &Section, const ObjectFile *obj) {
186  StringRef Name;
187  checkError(Section.getName(Name), "SectionRef::getName() failed");
188  uint64_t Addr, Size, Align;
189  checkError(Section.getAddress(Addr), "SectionRef::getAddress() failed");
190  checkError(Section.getSize(Size), "SectionRef::getSize() failed");
191  checkError(Section.getAlignment(Align), "SectionRef::getAlignment() failed");
192  outs() << format("  %-24s", std::string(Name).c_str())
193         << format("  %16" PRIx64, Addr)
194         << format("  %16" PRIx64, Size)
195         << format("  %8" PRIx64, Align)
196         << "  " << getSectionFlagStr(Section)
197         << "\n";
198}
199
200static void dumpLibrary(const LibraryRef &lib, const ObjectFile *obj) {
201  StringRef path;
202  lib.getPath(path);
203  outs() << "  " << path << "\n";
204}
205
206template<typename Iterator, typename Func>
207static void dump(const ObjectFile *obj, Func f, Iterator begin, Iterator end,
208                 const char *errStr) {
209  error_code ec;
210  uint32_t count = 0;
211  Iterator it = begin, ie = end;
212  while (it != ie) {
213    f(*it, obj);
214    it.increment(ec);
215    if (ec)
216      report_fatal_error(errStr);
217    ++count;
218  }
219  outs() << "  Total: " << count << "\n\n";
220}
221
222static void dumpHeaders(const ObjectFile *obj) {
223  outs() << "File Format : " << obj->getFileFormatName() << "\n";
224  outs() << "Arch        : "
225         << Triple::getArchTypeName((llvm::Triple::ArchType)obj->getArch())
226         << "\n";
227  outs() << "Address Size: " << (8*obj->getBytesInAddress()) << " bits\n";
228  outs() << "Load Name   : " << obj->getLoadName() << "\n";
229  outs() << "\n";
230}
231
232int main(int argc, char** argv) {
233  error_code ec;
234  sys::PrintStackTraceOnErrorSignal();
235  PrettyStackTraceProgram X(argc, argv);
236
237  cl::ParseCommandLineOptions(argc, argv,
238                              "LLVM Object Reader\n");
239
240  if (InputFilename.empty()) {
241    errs() << "Please specify an input filename\n";
242    return 1;
243  }
244
245  // Open the object file
246  OwningPtr<MemoryBuffer> File;
247  if (MemoryBuffer::getFile(InputFilename, File)) {
248    errs() << InputFilename << ": Open failed\n";
249    return 1;
250  }
251
252  OwningPtr<ObjectFile> o(ObjectFile::createObjectFile(File.take()));
253  ObjectFile *obj = o.get();
254  if (!obj) {
255    errs() << InputFilename << ": Object type not recognized\n";
256  }
257
258  dumpHeaders(obj);
259
260  outs() << "Symbols:\n";
261  dumpSymbolHeader();
262  dump(obj, dumpStaticSymbol, obj->begin_symbols(), obj->end_symbols(),
263       "Symbol iteration failed");
264
265  outs() << "Dynamic Symbols:\n";
266  dumpSymbolHeader();
267  dump(obj, dumpDynamicSymbol, obj->begin_dynamic_symbols(),
268       obj->end_dynamic_symbols(), "Symbol iteration failed");
269
270  outs() << "Sections:\n";
271  dumpSectionHeader();
272  dump(obj, &dumpSection, obj->begin_sections(), obj->end_sections(),
273       "Section iteration failed");
274
275  if (obj->isELF()) {
276    if (ErrorOr<void> e = dumpELFDynamicTable(obj, outs()))
277      ;
278    else
279      errs() << "InputFilename" << ": " << error_code(e).message() << "\n";
280  }
281
282  outs() << "Libraries needed:\n";
283  dump(obj, &dumpLibrary, obj->begin_libraries_needed(),
284       obj->end_libraries_needed(), "Needed libraries iteration failed");
285
286  return 0;
287}
288
289