llvm-readobj.cpp revision 663cebc4ad5ac5ad77ac051cbb925a126bba2c23 
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 const char *getTypeStr(SymbolRef::Type Type) {
37  switch (Type) {
38  case SymbolRef::ST_Unknown: return "?";
39  case SymbolRef::ST_Data: return "DATA";
40  case SymbolRef::ST_Debug: return "DBG";
41  case SymbolRef::ST_File: return "FILE";
42  case SymbolRef::ST_Function: return "FUNC";
43  case SymbolRef::ST_Other: return "-";
44  }
45  return "INV";
46}
47
48static std::string getSymbolFlagStr(uint32_t Flags) {
49  std::string result;
50  if (Flags & SymbolRef::SF_Undefined)
51    result += "undef,";
52  if (Flags & SymbolRef::SF_Global)
53    result += "global,";
54  if (Flags & SymbolRef::SF_Weak)
55    result += "weak,";
56  if (Flags & SymbolRef::SF_Absolute)
57    result += "absolute,";
58  if (Flags & SymbolRef::SF_ThreadLocal)
59    result += "threadlocal,";
60  if (Flags & SymbolRef::SF_Common)
61    result += "common,";
62  if (Flags & SymbolRef::SF_FormatSpecific)
63    result += "formatspecific,";
64
65  // Remove trailing comma
66  if (result.size() > 0) {
67    result.erase(result.size() - 1);
68  }
69  return result;
70}
71
72static void
73dumpSymbol(const SymbolRef &Sym, const ObjectFile *obj, bool IsDynamic) {
74    StringRef Name;
75    SymbolRef::Type Type;
76    uint32_t Flags;
77    uint64_t Address;
78    uint64_t Size;
79    uint64_t FileOffset;
80    Sym.getName(Name);
81    Sym.getAddress(Address);
82    Sym.getSize(Size);
83    Sym.getFileOffset(FileOffset);
84    Sym.getType(Type);
85    Sym.getFlags(Flags);
86    std::string FullName = Name;
87
88    // If this is a dynamic symbol from an ELF object, append
89    // the symbol's version to the name.
90    if (IsDynamic && obj->isELF()) {
91      StringRef Version;
92      bool IsDefault;
93      GetELFSymbolVersion(obj, Sym, Version, IsDefault);
94      if (!Version.empty()) {
95        FullName += (IsDefault ? "@@" : "@");
96        FullName += Version;
97      }
98    }
99
100    // format() can't handle StringRefs
101    outs() << format("  %-32s", FullName.c_str())
102           << format("  %-4s", getTypeStr(Type))
103           << format("  %16" PRIx64, Address)
104           << format("  %16" PRIx64, Size)
105           << format("  %16" PRIx64, FileOffset)
106           << "  " << getSymbolFlagStr(Flags)
107           << "\n";
108}
109
110// Iterate through the normal symbols in the ObjectFile
111static void dumpSymbols(const ObjectFile *obj) {
112  error_code ec;
113  uint32_t count = 0;
114  outs() << "Symbols:\n";
115  symbol_iterator it = obj->begin_symbols();
116  symbol_iterator ie = obj->end_symbols();
117  while (it != ie) {
118    dumpSymbol(*it, obj, false);
119    it.increment(ec);
120    if (ec)
121      report_fatal_error("Symbol iteration failed");
122    ++count;
123  }
124  outs() << "  Total: " << count << "\n\n";
125}
126
127// Iterate through the dynamic symbols in the ObjectFile.
128static void dumpDynamicSymbols(const ObjectFile *obj) {
129  error_code ec;
130  uint32_t count = 0;
131  outs() << "Dynamic Symbols:\n";
132  symbol_iterator it = obj->begin_dynamic_symbols();
133  symbol_iterator ie = obj->end_dynamic_symbols();
134  while (it != ie) {
135    dumpSymbol(*it, obj, true);
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
144static void dumpLibrary(const LibraryRef &lib) {
145  StringRef path;
146  lib.getPath(path);
147  outs() << "  " << path << "\n";
148}
149
150// Iterate through needed libraries
151static void dumpLibrariesNeeded(const ObjectFile *obj) {
152  error_code ec;
153  uint32_t count = 0;
154  library_iterator it = obj->begin_libraries_needed();
155  library_iterator ie = obj->end_libraries_needed();
156  outs() << "Libraries needed:\n";
157  while (it != ie) {
158    dumpLibrary(*it);
159    it.increment(ec);
160    if (ec)
161      report_fatal_error("Needed libraries iteration failed");
162    ++count;
163  }
164  outs() << "  Total: " << count << "\n\n";
165}
166
167static void dumpHeaders(const ObjectFile *obj) {
168  outs() << "File Format : " << obj->getFileFormatName() << "\n";
169  outs() << "Arch        : "
170         << Triple::getArchTypeName((llvm::Triple::ArchType)obj->getArch())
171         << "\n";
172  outs() << "Address Size: " << (8*obj->getBytesInAddress()) << " bits\n";
173  outs() << "Load Name   : " << obj->getLoadName() << "\n";
174  outs() << "\n";
175}
176
177int main(int argc, char** argv) {
178  error_code ec;
179  sys::PrintStackTraceOnErrorSignal();
180  PrettyStackTraceProgram X(argc, argv);
181
182  cl::ParseCommandLineOptions(argc, argv,
183                              "LLVM Object Reader\n");
184
185  if (InputFilename.empty()) {
186    errs() << "Please specify an input filename\n";
187    return 1;
188  }
189
190  // Open the object file
191  OwningPtr<MemoryBuffer> File;
192  if (MemoryBuffer::getFile(InputFilename, File)) {
193    errs() << InputFilename << ": Open failed\n";
194    return 1;
195  }
196
197  ObjectFile *obj = ObjectFile::createObjectFile(File.take());
198  if (!obj) {
199    errs() << InputFilename << ": Object type not recognized\n";
200  }
201
202  dumpHeaders(obj);
203  dumpSymbols(obj);
204  dumpDynamicSymbols(obj);
205  dumpLibrariesNeeded(obj);
206  return 0;
207}
208
209