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 ObjDumper::ObjDumper(ScopedPrinter &Writer) : W(Writer) {}
  27
  28 ObjDumper::~ObjDumper() {
  29 }
  30
  31 static void printAsPrintable(raw_ostream &W, const uint8_t *Start, size_t Len) {
  32   for (size_t i = 0; i < Len; i++)
  33     W << (isPrint(Start[i]) ? static_cast<char>(Start[i]) : '.');
  34 }
  35
  36 static std::vector<object::SectionRef>
  37 getSectionRefsByNameOrIndex(const object::ObjectFile *Obj,
  38                             ArrayRef<std::string> Sections) {
  39   std::vector<object::SectionRef> Ret;
  40   std::map<std::string, bool> SecNames;
  41   std::map<unsigned, bool> SecIndices;
  42   unsigned SecIndex;
  43   for (StringRef Section : Sections) {
  44     if (!Section.getAsInteger(0, SecIndex))
  45       SecIndices.emplace(SecIndex, false);
  46     else
  47       SecNames.emplace(Section, false);
  48   }
  49
  50   SecIndex = Obj->isELF() ? 0 : 1;
  51   for (object::SectionRef SecRef : Obj->sections()) {
  52     StringRef SecName;
  53     error(SecRef.getName(SecName));
  54     auto NameIt = SecNames.find(SecName);
  55     if (NameIt != SecNames.end())
  56       NameIt->second = true;
  57     auto IndexIt = SecIndices.find(SecIndex);
  58     if (IndexIt != SecIndices.end())
  59       IndexIt->second = true;
  60     if (NameIt != SecNames.end() || IndexIt != SecIndices.end())
  61       Ret.push_back(SecRef);
  62     SecIndex++;
  63   }
  64
  65   for (const std::pair<std::string, bool> &S : SecNames)
  66     if (!S.second)
  67       reportWarning(formatv("could not find section '{0}'", S.first).str());
  68   for (std::pair<unsigned, bool> S : SecIndices)
  69     if (!S.second)
  70       reportWarning(formatv("could not find section {0}", S.first).str());
  71
  72   return Ret;
  73 }
  74
  75 void ObjDumper::printSectionsAsString(const object::ObjectFile *Obj,
  76                                       ArrayRef<std::string> Sections) {
  77   bool First = true;
  78   for (object::SectionRef Section :
  79        getSectionRefsByNameOrIndex(Obj, Sections)) {
  80     StringRef SectionName;
  81     error(Section.getName(SectionName));
  82     if (!First)
  83       W.startLine() << '\n';
  84     First = false;
  85     W.startLine() << "String dump of section '" << SectionName << "':\n";
  86
  87     StringRef SectionContent = unwrapOrError(Section.getContents());
  88
  89     const uint8_t *SecContent = SectionContent.bytes_begin();
  90     const uint8_t *CurrentWord = SecContent;
  91     const uint8_t *SecEnd = SectionContent.bytes_end();
  92
  93     while (CurrentWord <= SecEnd) {
  94       size_t WordSize = strnlen(reinterpret_cast<const char *>(CurrentWord),
  95                                 SecEnd - CurrentWord);
  96       if (!WordSize) {
  97         CurrentWord++;
  98         continue;
  99       }
 100       W.startLine() << format("[%6tx] ", CurrentWord - SecContent);
 101       printAsPrintable(W.startLine(), CurrentWord, WordSize);
 102       W.startLine() << '\n';
 103       CurrentWord += WordSize + 1;
 104     }
 105   }
 106 }
 107
 108 void ObjDumper::printSectionsAsHex(const object::ObjectFile *Obj,
 109                                    ArrayRef<std::string> Sections) {
 110   bool First = true;
 111   for (object::SectionRef Section :
 112        getSectionRefsByNameOrIndex(Obj, Sections)) {
 113     StringRef SectionName;
 114     error(Section.getName(SectionName));
 115     if (!First)
 116       W.startLine() << '\n';
 117     First = false;
 118     W.startLine() << "Hex dump of section '" << SectionName << "':\n";
 119
 120     StringRef SectionContent = unwrapOrError(Section.getContents());
 121     const uint8_t *SecContent = SectionContent.bytes_begin();
 122     const uint8_t *SecEnd = SecContent + SectionContent.size();
 123
 124     for (const uint8_t *SecPtr = SecContent; SecPtr < SecEnd; SecPtr += 16) {
 125       const uint8_t *TmpSecPtr = SecPtr;
 126       uint8_t i;
 127       uint8_t k;
 128
 129       W.startLine() << format_hex(Section.getAddress() + (SecPtr - SecContent),
 130                                   10);
 131       W.startLine() << ' ';
 132       for (i = 0; TmpSecPtr < SecEnd && i < 4; ++i) {
 133         for (k = 0; TmpSecPtr < SecEnd && k < 4; k++, TmpSecPtr++) {
 134           uint8_t Val = *(reinterpret_cast<const uint8_t *>(TmpSecPtr));
 135           W.startLine() << format_hex_no_prefix(Val, 2);
 136         }
 137         W.startLine() << ' ';
 138       }
 139
 140       // We need to print the correct amount of spaces to match the format.
 141       // We are adding the (4 - i) last rows that are 8 characters each.
 142       // Then, the (4 - i) spaces that are in between the rows.
 143       // Least, if we cut in a middle of a row, we add the remaining characters,
 144       // which is (8 - (k * 2)).
 145       if (i < 4)
 146         W.startLine() << format("%*c", (4 - i) * 8 + (4 - i) + (8 - (k * 2)),
 147                                 ' ');
 148
 149       TmpSecPtr = SecPtr;
 150       for (i = 0; TmpSecPtr + i < SecEnd && i < 16; ++i)
 151         W.startLine() << (isPrint(TmpSecPtr[i])
 152                               ? static_cast<char>(TmpSecPtr[i])
 153                               : '.');
 154
 155       W.startLine() << '\n';
 156     }
 157   }
 158 }
 159
 160 } // namespace llvm