llvm/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 "Opts.inc"
  15 #include "llvm/ADT/StringExtras.h"
  16 #include "llvm/Object/Binary.h"
  17 #include "llvm/Option/Arg.h"
  18 #include "llvm/Option/ArgList.h"
  19 #include "llvm/Option/Option.h"
  20 #include "llvm/Support/CommandLine.h"
  21 #include "llvm/Support/Error.h"
  22 #include "llvm/Support/Format.h"
  23 #include "llvm/Support/InitLLVM.h"
  24 #include "llvm/Support/MemoryBuffer.h"
  25 #include "llvm/Support/Program.h"
  26 #include "llvm/Support/WithColor.h"
  27 #include <cctype>
  28 #include <string>
  29
  30 using namespace llvm;
  31 using namespace llvm::object;
  32
  33 namespace {
  34 enum ID {
  35   OPT_INVALID = 0, // This is not an option ID.
  36 #define OPTION(...) LLVM_MAKE_OPT_ID(__VA_ARGS__),
  37 #include "Opts.inc"
  38 #undef OPTION
  39 };
  40
  41 #define PREFIX(NAME, VALUE)                                                    \
  42   static constexpr StringLiteral NAME##_init[] = VALUE;                        \
  43   static constexpr ArrayRef<StringLiteral> NAME(NAME##_init,                   \
  44                                                 std::size(NAME##_init) - 1);
  45 #include "Opts.inc"
  46 #undef PREFIX
  47
  48 using namespace llvm::opt;
  49 static constexpr opt::OptTable::Info InfoTable[] = {
  50 #define OPTION(...) LLVM_CONSTRUCT_OPT_INFO(__VA_ARGS__),
  51 #include "Opts.inc"
  52 #undef OPTION
  53 };
  54
  55 class StringsOptTable : public opt::GenericOptTable {
  56 public:
  57   StringsOptTable() : GenericOptTable(InfoTable) {
  58     setGroupedShortOptions(true);
  59     setDashDashParsing(true);
  60   }
  61 };
  62 } // namespace
  63
  64 static StringRef ToolName;
  65
  66 static cl::list<std::string> InputFileNames(cl::Positional,
  67                                             cl::desc("<input object files>"));
  68
  69 static int MinLength = 4;
  70 static bool PrintFileName;
  71
  72 enum radix { none, octal, hexadecimal, decimal };
  73 static radix Radix;
  74
  75 [[noreturn]] static void reportCmdLineError(const Twine &Message) {
  76   WithColor::error(errs(), ToolName) << Message << "\n";
  77   exit(1);
  78 }
  79
  80 template <typename T>
  81 static void parseIntArg(const opt::InputArgList &Args, int ID, T &Value) {
  82   if (const opt::Arg *A = Args.getLastArg(ID)) {
  83     StringRef V(A->getValue());
  84     if (!llvm::to_integer(V, Value, 0) || Value <= 0)
  85       reportCmdLineError("expected a positive integer, but got '" + V + "'");
  86   }
  87 }
  88
  89 static void strings(raw_ostream &OS, StringRef FileName, StringRef Contents) {
  90   auto print = [&OS, FileName](unsigned Offset, StringRef L) {
  91     if (L.size() < static_cast<size_t>(MinLength))
  92       return;
  93     if (PrintFileName)
  94       OS << FileName << ": ";
  95     switch (Radix) {
  96     case none:
  97       break;
  98     case octal:
  99       OS << format("%7o ", Offset);
 100       break;
 101     case hexadecimal:
 102       OS << format("%7x ", Offset);
 103       break;
 104     case decimal:
 105       OS << format("%7u ", Offset);
 106       break;
 107     }
 108     OS << L << '\n';
 109   };
 110
 111   const char *B = Contents.begin();
 112   const char *P = nullptr, *E = nullptr, *S = nullptr;
 113   for (P = Contents.begin(), E = Contents.end(); P < E; ++P) {
 114     if (isPrint(*P) || *P == '\t') {
 115       if (S == nullptr)
 116         S = P;
 117     } else if (S) {
 118       print(S - B, StringRef(S, P - S));
 119       S = nullptr;
 120     }
 121   }
 122   if (S)
 123     print(S - B, StringRef(S, E - S));
 124 }
 125
 126 int main(int argc, char **argv) {
 127   InitLLVM X(argc, argv);
 128   BumpPtrAllocator A;
 129   StringSaver Saver(A);
 130   StringsOptTable Tbl;
 131   ToolName = argv[0];
 132   opt::InputArgList Args =
 133       Tbl.parseArgs(argc, argv, OPT_UNKNOWN, Saver,
 134                     [&](StringRef Msg) { reportCmdLineError(Msg); });
 135   if (Args.hasArg(OPT_help)) {
 136     Tbl.printHelp(
 137         outs(),
 138         (Twine(ToolName) + " [options] <input object files>").str().c_str(),
 139         "llvm string dumper");
 140     // TODO Replace this with OptTable API once it adds extrahelp support.
 141     outs() << "\nPass @FILE as argument to read options from FILE.\n";
 142     return 0;
 143   }
 144   if (Args.hasArg(OPT_version)) {
 145     outs() << ToolName << '\n';
 146     cl::PrintVersionMessage();
 147     return 0;
 148   }
 149
 150   parseIntArg(Args, OPT_bytes_EQ, MinLength);
 151   PrintFileName = Args.hasArg(OPT_print_file_name);
 152   StringRef R = Args.getLastArgValue(OPT_radix_EQ);
 153   if (R.empty())
 154     Radix = none;
 155   else if (R == "o")
 156     Radix = octal;
 157   else if (R == "d")
 158     Radix = decimal;
 159   else if (R == "x")
 160     Radix = hexadecimal;
 161   else
 162     reportCmdLineError("--radix value should be one of: '' (no offset), 'o' "
 163                        "(octal), 'd' (decimal), 'x' (hexadecimal)");
 164
 165   if (MinLength == 0) {
 166     errs() << "invalid minimum string length 0\n";
 167     return EXIT_FAILURE;
 168   }
 169
 170   std::vector<std::string> InputFileNames = Args.getAllArgValues(OPT_INPUT);
 171   if (InputFileNames.empty())
 172     InputFileNames.push_back("-");
 173
 174   for (const auto &File : InputFileNames) {
 175     ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
 176         MemoryBuffer::getFileOrSTDIN(File, /*IsText=*/true);
 177     if (std::error_code EC = Buffer.getError())
 178       errs() << File << ": " << EC.message() << '\n';
 179     else
 180       strings(llvm::outs(), File == "-" ? "{standard input}" : File,
 181               Buffer.get()->getMemBufferRef().getBuffer());
 182   }
 183
 184   return EXIT_SUCCESS;
 185 }