tools/llvm-strings/llvm-strings.cpp

   1 //===-- llvm-strings.cpp - Printable String dumping utility ---------------===//
   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 // This program is a utility that works like binutils "strings", that is, it
  10 // prints out printable strings in a binary, objdump, or archive file.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Object/Binary.h"
  15 #include "llvm/Support/CommandLine.h"
  16 #include "llvm/Support/Error.h"
  17 #include "llvm/Support/Format.h"
  18 #include "llvm/Support/InitLLVM.h"
  19 #include "llvm/Support/MemoryBuffer.h"
  20 #include "llvm/Support/Program.h"
  21 #include <cctype>
  22 #include <string>
  23
  24 using namespace llvm;
  25 using namespace llvm::object;
  26
  27 static cl::list<std::string> InputFileNames(cl::Positional,
  28                                             cl::desc("<input object files>"),
  29                                             cl::ZeroOrMore);
  30
  31 static cl::opt<bool>
  32     PrintFileName("print-file-name",
  33                   cl::desc("Print the name of the file before each string"));
  34 static cl::alias PrintFileNameShort("f", cl::desc(""),
  35                                     cl::aliasopt(PrintFileName));
  36
  37 static cl::opt<int>
  38     MinLength("bytes", cl::desc("Print sequences of the specified length"),
  39               cl::init(4));
  40 static cl::alias MinLengthShort("n", cl::desc(""), cl::aliasopt(MinLength));
  41
  42 static cl::opt<bool>
  43     AllSections("all",
  44                   cl::desc("Check all sections, not just the data section"));
  45 static cl::alias AllSectionsShort("a", cl::desc(""),
  46                                     cl::aliasopt(AllSections));
  47
  48 enum radix { none, octal, hexadecimal, decimal };
  49 static cl::opt<radix>
  50     Radix("radix", cl::desc("print the offset within the file"),
  51           cl::values(clEnumValN(octal, "o", "octal"),
  52                      clEnumValN(hexadecimal, "x", "hexadecimal"),
  53                      clEnumValN(decimal, "d", "decimal")),
  54           cl::init(none));
  55 static cl::alias RadixShort("t", cl::desc(""), cl::aliasopt(Radix));
  56
  57 static cl::extrahelp
  58     HelpResponse("\nPass @FILE as argument to read options from FILE.\n");
  59
  60 static void strings(raw_ostream &OS, StringRef FileName, StringRef Contents) {
  61   auto print = [&OS, FileName](unsigned Offset, StringRef L) {
  62     if (L.size() < static_cast<size_t>(MinLength))
  63       return;
  64     if (PrintFileName)
  65       OS << FileName << ": ";
  66     switch (Radix) {
  67     case none:
  68       break;
  69     case octal:
  70       OS << format("%7o ", Offset);
  71       break;
  72     case hexadecimal:
  73       OS << format("%7x ", Offset);
  74       break;
  75     case decimal:
  76       OS << format("%7u ", Offset);
  77       break;
  78     }
  79     OS << L << '\n';
  80   };
  81
  82   const char *B = Contents.begin();
  83   const char *P = nullptr, *E = nullptr, *S = nullptr;
  84   for (P = Contents.begin(), E = Contents.end(); P < E; ++P) {
  85     if (isPrint(*P) || *P == '\t') {
  86       if (S == nullptr)
  87         S = P;
  88     } else if (S) {
  89       print(S - B, StringRef(S, P - S));
  90       S = nullptr;
  91     }
  92   }
  93   if (S)
  94     print(S - B, StringRef(S, E - S));
  95 }
  96
  97 int main(int argc, char **argv) {
  98   InitLLVM X(argc, argv);
  99
 100   cl::ParseCommandLineOptions(argc, argv, "llvm string dumper\n");
 101   if (MinLength == 0) {
 102     errs() << "invalid minimum string length 0\n";
 103     return EXIT_FAILURE;
 104   }
 105
 106   if (InputFileNames.empty())
 107     InputFileNames.push_back("-");
 108
 109   for (const auto &File : InputFileNames) {
 110     ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
 111         MemoryBuffer::getFileOrSTDIN(File);
 112     if (std::error_code EC = Buffer.getError())
 113       errs() << File << ": " << EC.message() << '\n';
 114     else
 115       strings(llvm::outs(), File == "-" ? "{standard input}" : File,
 116               Buffer.get()->getMemBufferRef().getBuffer());
 117   }
 118
 119   return EXIT_SUCCESS;
 120 }