tools/llvm-readobj/ObjDumper.cpp

   1 //===-- ObjDumper.cpp - Base dumper class -----------------------*- C++ -*-===//
   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 /// \file
  11 /// This file implements ObjDumper.
  12 ///
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "ObjDumper.h"
  16 #include "Error.h"
  17 #include "llvm-readobj.h"
  18 #include "llvm/Object/ObjectFile.h"
  19 #include "llvm/Support/Error.h"
  20 #include "llvm/Support/ScopedPrinter.h"
  21 #include "llvm/Support/raw_ostream.h"
  22
  23 namespace llvm {
  24
  25 ObjDumper::ObjDumper(ScopedPrinter &Writer) : W(Writer) {}
  26
  27 ObjDumper::~ObjDumper() {
  28 }
  29
  30 static void printAsPrintable(raw_ostream &W, const uint8_t *Start, size_t Len) {
  31   for (size_t i = 0; i < Len; i++)
  32     W << (isPrint(Start[i]) ? static_cast<char>(Start[i]) : '.');
  33 }
  34
  35 static Expected<object::SectionRef>
  36 getSecNameOrIndexAsSecRef(const object::ObjectFile *Obj, StringRef SecName) {
  37   char *StrPtr;
  38   long SectionIndex = strtol(SecName.data(), &StrPtr, 10);
  39   object::SectionRef Section;
  40   long SecIndex;
  41   if (Obj->isELF())
  42     SecIndex = 0;
  43   else
  44     SecIndex = 1;
  45   for (object::SectionRef SecRef : Obj->sections()) {
  46     if (*StrPtr) {
  47       StringRef SectionName;
  48
  49       if (std::error_code E = SecRef.getName(SectionName))
  50         return errorCodeToError(E);
  51
  52       if (SectionName == SecName)
  53         return SecRef;
  54     } else if (SecIndex == SectionIndex)
  55       return SecRef;
  56
  57     SecIndex++;
  58   }
  59   return make_error<StringError>("invalid section reference",
  60                                  object::object_error::parse_failed);
  61 }
  62
  63 void ObjDumper::printSectionAsString(const object::ObjectFile *Obj,
  64                                      StringRef SecName) {
  65   Expected<object::SectionRef> SectionRefOrError =
  66       getSecNameOrIndexAsSecRef(Obj, SecName);
  67   if (!SectionRefOrError)
  68     error(std::move(SectionRefOrError));
  69   object::SectionRef Section = *SectionRefOrError;
  70   StringRef SectionName;
  71
  72   if (std::error_code E = Section.getName(SectionName))
  73     error(E);
  74   W.startLine() << "String dump of section '" << SectionName << "':\n";
  75
  76   StringRef SectionContent;
  77   Section.getContents(SectionContent);
  78
  79   const uint8_t *SecContent = SectionContent.bytes_begin();
  80   const uint8_t *CurrentWord = SecContent;
  81   const uint8_t *SecEnd = SectionContent.bytes_end();
  82
  83   while (CurrentWord <= SecEnd) {
  84     size_t WordSize = strnlen(reinterpret_cast<const char *>(CurrentWord),
  85                               SecEnd - CurrentWord);
  86     if (!WordSize) {
  87       CurrentWord++;
  88       continue;
  89     }
  90     W.startLine() << format("[%6tx] ", CurrentWord - SecContent);
  91     printAsPrintable(W.startLine(), CurrentWord, WordSize);
  92     W.startLine() << '\n';
  93     CurrentWord += WordSize + 1;
  94   }
  95 }
  96
  97 void ObjDumper::printSectionAsHex(const object::ObjectFile *Obj,
  98                                   StringRef SecName) {
  99   Expected<object::SectionRef> SectionRefOrError =
 100       getSecNameOrIndexAsSecRef(Obj, SecName);
 101   if (!SectionRefOrError)
 102     error(std::move(SectionRefOrError));
 103   object::SectionRef Section = *SectionRefOrError;
 104   StringRef SectionName;
 105
 106   if (std::error_code E = Section.getName(SectionName))
 107     error(E);
 108   W.startLine() << "Hex dump of section '" << SectionName << "':\n";
 109
 110   StringRef SectionContent;
 111   Section.getContents(SectionContent);
 112   const uint8_t *SecContent = SectionContent.bytes_begin();
 113   const uint8_t *SecEnd = SecContent + SectionContent.size();
 114
 115   for (const uint8_t *SecPtr = SecContent; SecPtr < SecEnd; SecPtr += 16) {
 116     const uint8_t *TmpSecPtr = SecPtr;
 117     uint8_t i;
 118     uint8_t k;
 119
 120     W.startLine() << format_hex(SecPtr - SecContent, 10);
 121     W.startLine() << ' ';
 122     for (i = 0; TmpSecPtr < SecEnd && i < 4; ++i) {
 123       for (k = 0; TmpSecPtr < SecEnd && k < 4; k++, TmpSecPtr++) {
 124         uint8_t Val = *(reinterpret_cast<const uint8_t *>(TmpSecPtr));
 125         W.startLine() << format_hex_no_prefix(Val, 2);
 126       }
 127       W.startLine() << ' ';
 128     }
 129
 130     // We need to print the correct amount of spaces to match the format.
 131     // We are adding the (4 - i) last rows that are 8 characters each.
 132     // Then, the (4 - i) spaces that are in between the rows.
 133     // Least, if we cut in a middle of a row, we add the remaining characters,
 134     // which is (8 - (k * 2))
 135     if (i < 4)
 136       W.startLine() << format("%*c", (4 - i) * 8 + (4 - i) + (8 - (k * 2)),
 137                               ' ');
 138
 139     TmpSecPtr = SecPtr;
 140     for (i = 0; TmpSecPtr + i < SecEnd && i < 16; ++i)
 141       W.startLine() << (isPrint(TmpSecPtr[i]) ? static_cast<char>(TmpSecPtr[i])
 142                                               : '.');
 143
 144     W.startLine() << '\n';
 145   }
 146 }
 147
 148 } // namespace llvm