tools/llvm-readobj/ObjDumper.cpp

   1 //===-- ObjDumper.cpp - Base dumper class -----------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 ///
   9 /// \file
  10 /// This file implements ObjDumper.
  11 ///
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "ObjDumper.h"
  15 #include "Error.h"
  16 #include "llvm-readobj.h"
  17 #include "llvm/Object/ObjectFile.h"
  18 #include "llvm/Support/Error.h"
  19 #include "llvm/Support/FormatVariadic.h"
  20 #include "llvm/Support/ScopedPrinter.h"
  21 #include "llvm/Support/raw_ostream.h"
  22 #include <map>
  23
  24 namespace llvm {
  25
  26 static inline Error createError(const Twine &Msg) {
  27   return createStringError(object::object_error::parse_failed, Msg);
  28 }
  29
  30 ObjDumper::ObjDumper(ScopedPrinter &Writer) : W(Writer) {}
  31
  32 ObjDumper::~ObjDumper() {
  33 }
  34
  35 static void printAsPrintable(raw_ostream &W, const uint8_t *Start, size_t Len) {
  36   for (size_t i = 0; i < Len; i++)
  37     W << (isPrint(Start[i]) ? static_cast<char>(Start[i]) : '.');
  38 }
  39
  40 static std::vector<object::SectionRef>
  41 getSectionRefsByNameOrIndex(const object::ObjectFile *Obj,
  42                             ArrayRef<std::string> Sections) {
  43   std::vector<object::SectionRef> Ret;
  44   std::map<std::string, bool> SecNames;
  45   std::map<unsigned, bool> SecIndices;
  46   unsigned SecIndex;
  47   for (StringRef Section : Sections) {
  48     if (!Section.getAsInteger(0, SecIndex))
  49       SecIndices.emplace(SecIndex, false);
  50     else
  51       SecNames.emplace(Section, false);
  52   }
  53
  54   SecIndex = Obj->isELF() ? 0 : 1;
  55   for (object::SectionRef SecRef : Obj->sections()) {
  56     StringRef SecName = unwrapOrError(Obj->getFileName(), SecRef.getName());
  57     auto NameIt = SecNames.find(SecName);
  58     if (NameIt != SecNames.end())
  59       NameIt->second = true;
  60     auto IndexIt = SecIndices.find(SecIndex);
  61     if (IndexIt != SecIndices.end())
  62       IndexIt->second = true;
  63     if (NameIt != SecNames.end() || IndexIt != SecIndices.end())
  64       Ret.push_back(SecRef);
  65     SecIndex++;
  66   }
  67
  68   for (const std::pair<std::string, bool> &S : SecNames)
  69     if (!S.second)
  70       reportWarning(
  71           createError(formatv("could not find section '{0}'", S.first).str()),
  72           Obj->getFileName());
  73
  74   for (std::pair<unsigned, bool> S : SecIndices)
  75     if (!S.second)
  76       reportWarning(
  77           createError(formatv("could not find section {0}", S.first).str()),
  78           Obj->getFileName());
  79
  80   return Ret;
  81 }
  82
  83 void ObjDumper::printSectionsAsString(const object::ObjectFile *Obj,
  84                                       ArrayRef<std::string> Sections) {
  85   bool First = true;
  86   for (object::SectionRef Section :
  87        getSectionRefsByNameOrIndex(Obj, Sections)) {
  88     StringRef SectionName =
  89         unwrapOrError(Obj->getFileName(), Section.getName());
  90
  91     if (!First)
  92       W.startLine() << '\n';
  93     First = false;
  94     W.startLine() << "String dump of section '" << SectionName << "':\n";
  95
  96     StringRef SectionContent =
  97         unwrapOrError(Obj->getFileName(), Section.getContents());
  98
  99     const uint8_t *SecContent = SectionContent.bytes_begin();
 100     const uint8_t *CurrentWord = SecContent;
 101     const uint8_t *SecEnd = SectionContent.bytes_end();
 102
 103     while (CurrentWord <= SecEnd) {
 104       size_t WordSize = strnlen(reinterpret_cast<const char *>(CurrentWord),
 105                                 SecEnd - CurrentWord);
 106       if (!WordSize) {
 107         CurrentWord++;
 108         continue;
 109       }
 110       W.startLine() << format("[%6tx] ", CurrentWord - SecContent);
 111       printAsPrintable(W.startLine(), CurrentWord, WordSize);
 112       W.startLine() << '\n';
 113       CurrentWord += WordSize + 1;
 114     }
 115   }
 116 }
 117
 118 void ObjDumper::printSectionsAsHex(const object::ObjectFile *Obj,
 119                                    ArrayRef<std::string> Sections) {
 120   bool First = true;
 121   for (object::SectionRef Section :
 122        getSectionRefsByNameOrIndex(Obj, Sections)) {
 123     StringRef SectionName =
 124         unwrapOrError(Obj->getFileName(), Section.getName());
 125
 126     if (!First)
 127       W.startLine() << '\n';
 128     First = false;
 129     W.startLine() << "Hex dump of section '" << SectionName << "':\n";
 130
 131     StringRef SectionContent =
 132         unwrapOrError(Obj->getFileName(), Section.getContents());
 133     const uint8_t *SecContent = SectionContent.bytes_begin();
 134     const uint8_t *SecEnd = SecContent + SectionContent.size();
 135
 136     for (const uint8_t *SecPtr = SecContent; SecPtr < SecEnd; SecPtr += 16) {
 137       const uint8_t *TmpSecPtr = SecPtr;
 138       uint8_t i;
 139       uint8_t k;
 140
 141       W.startLine() << format_hex(Section.getAddress() + (SecPtr - SecContent),
 142                                   10);
 143       W.startLine() << ' ';
 144       for (i = 0; TmpSecPtr < SecEnd && i < 4; ++i) {
 145         for (k = 0; TmpSecPtr < SecEnd && k < 4; k++, TmpSecPtr++) {
 146           uint8_t Val = *(reinterpret_cast<const uint8_t *>(TmpSecPtr));
 147           W.startLine() << format_hex_no_prefix(Val, 2);
 148         }
 149         W.startLine() << ' ';
 150       }
 151
 152       // We need to print the correct amount of spaces to match the format.
 153       // We are adding the (4 - i) last rows that are 8 characters each.
 154       // Then, the (4 - i) spaces that are in between the rows.
 155       // Least, if we cut in a middle of a row, we add the remaining characters,
 156       // which is (8 - (k * 2)).
 157       if (i < 4)
 158         W.startLine() << format("%*c", (4 - i) * 8 + (4 - i) + (8 - (k * 2)),
 159                                 ' ');
 160
 161       TmpSecPtr = SecPtr;
 162       for (i = 0; TmpSecPtr + i < SecEnd && i < 16; ++i)
 163         W.startLine() << (isPrint(TmpSecPtr[i])
 164                               ? static_cast<char>(TmpSecPtr[i])
 165                               : '.');
 166
 167       W.startLine() << '\n';
 168     }
 169   }
 170 }
 171
 172 } // namespace llvm