llvm-readobj.cpp revision 148ee4f224be6448834bf039807c70bb1a7c78f5 
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 program is a utility that works like traditional Unix "readelf",
11// except that it can handle any type of object file recognized by lib/Object.
12//
13// It makes use of the generic ObjectFile interface.
14//
15// Caution: This utility is new, experimental, unsupported, and incomplete.
16//
17//===----------------------------------------------------------------------===//
18
19#include "llvm/ADT/Triple.h"
20#include "llvm/Analysis/Verifier.h"
21#include "llvm/Object/ELF.h"
22#include "llvm/Object/ObjectFile.h"
23#include "llvm/Support/CommandLine.h"
24#include "llvm/Support/Debug.h"
25#include "llvm/Support/Format.h"
26#include "llvm/Support/FormattedStream.h"
27#include "llvm/Support/PrettyStackTrace.h"
28#include "llvm/Support/Signals.h"
29
30using namespace llvm;
31using namespace llvm::object;
32
33static cl::opt<std::string>
34InputFilename(cl::Positional, cl::desc("<input object>"), cl::init(""));
35
36static void dumpSymbolHeader() {
37  outs() << format("  %-32s", (const char*)"Name")
38         << format("  %-4s", (const char*)"Type")
39         << format("  %-16s", (const char*)"Address")
40         << format("  %-16s", (const char*)"Size")
41         << format("  %-16s", (const char*)"FileOffset")
42         << format("  %-26s", (const char*)"Flags")
43         << "\n";
44}
45
46static const char *getTypeStr(SymbolRef::Type Type) {
47  switch (Type) {
48  case SymbolRef::ST_Unknown: return "?";
49  case SymbolRef::ST_Data: return "DATA";
50  case SymbolRef::ST_Debug: return "DBG";
51  case SymbolRef::ST_File: return "FILE";
52  case SymbolRef::ST_Function: return "FUNC";
53  case SymbolRef::ST_Other: return "-";
54  }
55  return "INV";
56}
57
58static std::string getSymbolFlagStr(uint32_t Flags) {
59  std::string result;
60  if (Flags & SymbolRef::SF_Undefined)
61    result += "undef,";
62  if (Flags & SymbolRef::SF_Global)
63    result += "global,";
64  if (Flags & SymbolRef::SF_Weak)
65    result += "weak,";
66  if (Flags & SymbolRef::SF_Absolute)
67    result += "absolute,";
68  if (Flags & SymbolRef::SF_ThreadLocal)
69    result += "threadlocal,";
70  if (Flags & SymbolRef::SF_Common)
71    result += "common,";
72  if (Flags & SymbolRef::SF_FormatSpecific)
73    result += "formatspecific,";
74
75  // Remove trailing comma
76  if (result.size() > 0) {
77    result.erase(result.size() - 1);
78  }
79  return result;
80}
81
82static void checkError(error_code ec, const char *msg) {
83  if (ec)
84    report_fatal_error(std::string(msg) + ": " + ec.message());
85}
86
87static void
88dumpSymbol(const SymbolRef &Sym, const ObjectFile *obj, bool IsDynamic) {
89  StringRef Name;
90  SymbolRef::Type Type;
91  uint32_t Flags;
92  uint64_t Address;
93  uint64_t Size;
94  uint64_t FileOffset;
95  checkError(Sym.getName(Name), "SymbolRef.getName() failed");
96  checkError(Sym.getAddress(Address), "SymbolRef.getAddress() failed");
97  checkError(Sym.getSize(Size), "SymbolRef.getSize() failed");
98  checkError(Sym.getFileOffset(FileOffset),
99             "SymbolRef.getFileOffset() failed");
100  checkError(Sym.getType(Type), "SymbolRef.getType() failed");
101  checkError(Sym.getFlags(Flags), "SymbolRef.getFlags() failed");
102  std::string FullName = Name;
103
104  // If this is a dynamic symbol from an ELF object, append
105  // the symbol's version to the name.
106  if (IsDynamic && obj->isELF()) {
107    StringRef Version;
108    bool IsDefault;
109    GetELFSymbolVersion(obj, Sym, Version, IsDefault);
110    if (!Version.empty()) {
111      FullName += (IsDefault ? "@@" : "@");
112      FullName += Version;
113    }
114  }
115
116  // format() can't handle StringRefs
117  outs() << format("  %-32s", FullName.c_str())
118         << format("  %-4s", getTypeStr(Type))
119         << format("  %16" PRIx64, Address)
120         << format("  %16" PRIx64, Size)
121         << format("  %16" PRIx64, FileOffset)
122         << "  " << getSymbolFlagStr(Flags)
123         << "\n";
124}
125
126// Iterate through the normal symbols in the ObjectFile
127static void dumpSymbols(const ObjectFile *obj) {
128  error_code ec;
129  uint32_t count = 0;
130  outs() << "Symbols:\n";
131  dumpSymbolHeader();
132  symbol_iterator it = obj->begin_symbols();
133  symbol_iterator ie = obj->end_symbols();
134  while (it != ie) {
135    dumpSymbol(*it, obj, false);
136    it.increment(ec);
137    if (ec)
138      report_fatal_error("Symbol iteration failed");
139    ++count;
140  }
141  outs() << "  Total: " << count << "\n\n";
142}
143
144// Iterate through the dynamic symbols in the ObjectFile.
145static void dumpDynamicSymbols(const ObjectFile *obj) {
146  error_code ec;
147  uint32_t count = 0;
148  outs() << "Dynamic Symbols:\n";
149  dumpSymbolHeader();
150  symbol_iterator it = obj->begin_dynamic_symbols();
151  symbol_iterator ie = obj->end_dynamic_symbols();
152  while (it != ie) {
153    dumpSymbol(*it, obj, true);
154    it.increment(ec);
155    if (ec)
156      report_fatal_error("Symbol iteration failed");
157    ++count;
158  }
159  outs() << "  Total: " << count << "\n\n";
160}
161
162static void dumpLibrary(const LibraryRef &lib) {
163  StringRef path;
164  lib.getPath(path);
165  outs() << "  " << path << "\n";
166}
167
168// Iterate through needed libraries
169static void dumpLibrariesNeeded(const ObjectFile *obj) {
170  error_code ec;
171  uint32_t count = 0;
172  library_iterator it = obj->begin_libraries_needed();
173  library_iterator ie = obj->end_libraries_needed();
174  outs() << "Libraries needed:\n";
175  while (it != ie) {
176    dumpLibrary(*it);
177    it.increment(ec);
178    if (ec)
179      report_fatal_error("Needed libraries iteration failed");
180    ++count;
181  }
182  outs() << "  Total: " << count << "\n\n";
183}
184
185static void dumpHeaders(const ObjectFile *obj) {
186  outs() << "File Format : " << obj->getFileFormatName() << "\n";
187  outs() << "Arch        : "
188         << Triple::getArchTypeName((llvm::Triple::ArchType)obj->getArch())
189         << "\n";
190  outs() << "Address Size: " << (8*obj->getBytesInAddress()) << " bits\n";
191  outs() << "Load Name   : " << obj->getLoadName() << "\n";
192  outs() << "\n";
193}
194
195int main(int argc, char** argv) {
196  error_code ec;
197  sys::PrintStackTraceOnErrorSignal();
198  PrettyStackTraceProgram X(argc, argv);
199
200  cl::ParseCommandLineOptions(argc, argv,
201                              "LLVM Object Reader\n");
202
203  if (InputFilename.empty()) {
204    errs() << "Please specify an input filename\n";
205    return 1;
206  }
207
208  // Open the object file
209  OwningPtr<MemoryBuffer> File;
210  if (MemoryBuffer::getFile(InputFilename, File)) {
211    errs() << InputFilename << ": Open failed\n";
212    return 1;
213  }
214
215  ObjectFile *obj = ObjectFile::createObjectFile(File.take());
216  if (!obj) {
217    errs() << InputFilename << ": Object type not recognized\n";
218  }
219
220  dumpHeaders(obj);
221  dumpSymbols(obj);
222  dumpDynamicSymbols(obj);
223  dumpLibrariesNeeded(obj);
224  return 0;
225}
226
227