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/Object/Binary.h"
  16 #include "llvm/Option/Arg.h"
  17 #include "llvm/Option/ArgList.h"
  18 #include "llvm/Option/Option.h"
  19 #include "llvm/Support/CommandLine.h"
  20 #include "llvm/Support/Error.h"
  21 #include "llvm/Support/Format.h"
  22 #include "llvm/Support/InitLLVM.h"
  23 #include "llvm/Support/MemoryBuffer.h"
  24 #include "llvm/Support/Program.h"
  25 #include "llvm/Support/WithColor.h"
  26 #include <cctype>
  27 #include <string>
  28
  29 using namespace llvm;
  30 using namespace llvm::object;
  31
  32 namespace {
  33 enum ID {
  34   OPT_INVALID = 0, // This is not an option ID.
  35 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
  36                HELPTEXT, METAVAR, VALUES)                                      \
  37   OPT_##ID,
  38 #include "Opts.inc"
  39 #undef OPTION
  40 };
  41
  42 #define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
  43 #include "Opts.inc"
  44 #undef PREFIX
  45
  46 const opt::OptTable::Info InfoTable[] = {
  47 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
  48                HELPTEXT, METAVAR, VALUES)                                      \
  49   {                                                                            \
  50       PREFIX,      NAME,      HELPTEXT,                                        \
  51       METAVAR,     OPT_##ID,  opt::Option::KIND##Class,                        \
  52       PARAM,       FLAGS,     OPT_##GROUP,                                     \
  53       OPT_##ALIAS, ALIASARGS, VALUES},
  54 #include "Opts.inc"
  55 #undef OPTION
  56 };
  57
  58 class StringsOptTable : public opt::OptTable {
  59 public:
  60   StringsOptTable() : OptTable(InfoTable) { setGroupedShortOptions(true); }
  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                                             cl::ZeroOrMore);
  69
  70 static int MinLength = 4;
  71 static bool PrintFileName;
  72
  73 enum radix { none, octal, hexadecimal, decimal };
  74 static radix Radix;
  75
  76 [[noreturn]] static void reportCmdLineError(const Twine &Message) {
  77   WithColor::error(errs(), ToolName) << Message << "\n";
  78   exit(1);
  79 }
  80
  81 template <typename T>
  82 static void parseIntArg(const opt::InputArgList &Args, int ID, T &Value) {
  83   if (const opt::Arg *A = Args.getLastArg(ID)) {
  84     StringRef V(A->getValue());
  85     if (!llvm::to_integer(V, Value, 0) || Value <= 0)
  86       reportCmdLineError("expected a positive integer, but got '" + V + "'");
  87   }
  88 }
  89
  90 static void strings(raw_ostream &OS, StringRef FileName, StringRef Contents) {
  91   auto print = [&OS, FileName](unsigned Offset, StringRef L) {
  92     if (L.size() < static_cast<size_t>(MinLength))
  93       return;
  94     if (PrintFileName)
  95       OS << FileName << ": ";
  96     switch (Radix) {
  97     case none:
  98       break;
  99     case octal:
 100       OS << format("%7o ", Offset);
 101       break;
 102     case hexadecimal:
 103       OS << format("%7x ", Offset);
 104       break;
 105     case decimal:
 106       OS << format("%7u ", Offset);
 107       break;
 108     }
 109     OS << L << '\n';
 110   };
 111
 112   const char *B = Contents.begin();
 113   const char *P = nullptr, *E = nullptr, *S = nullptr;
 114   for (P = Contents.begin(), E = Contents.end(); P < E; ++P) {
 115     if (isPrint(*P) || *P == '\t') {
 116       if (S == nullptr)
 117         S = P;
 118     } else if (S) {
 119       print(S - B, StringRef(S, P - S));
 120       S = nullptr;
 121     }
 122   }
 123   if (S)
 124     print(S - B, StringRef(S, E - S));
 125 }
 126
 127 int main(int argc, char **argv) {
 128   InitLLVM X(argc, argv);
 129   BumpPtrAllocator A;
 130   StringSaver Saver(A);
 131   StringsOptTable Tbl;
 132   ToolName = argv[0];
 133   opt::InputArgList Args =
 134       Tbl.parseArgs(argc, argv, OPT_UNKNOWN, Saver,
 135                     [&](StringRef Msg) { reportCmdLineError(Msg); });
 136   if (Args.hasArg(OPT_help)) {
 137     Tbl.printHelp(
 138         outs(),
 139         (Twine(ToolName) + " [options] <input object files>").str().c_str(),
 140         "llvm string dumper");
 141     // TODO Replace this with OptTable API once it adds extrahelp support.
 142     outs() << "\nPass @FILE as argument to read options from FILE.\n";
 143     return 0;
 144   }
 145   if (Args.hasArg(OPT_version)) {
 146     outs() << ToolName << '\n';
 147     cl::PrintVersionMessage();
 148     return 0;
 149   }
 150
 151   parseIntArg(Args, OPT_bytes_EQ, MinLength);
 152   PrintFileName = Args.hasArg(OPT_print_file_name);
 153   StringRef R = Args.getLastArgValue(OPT_radix_EQ);
 154   if (R.empty())
 155     Radix = none;
 156   else if (R == "o")
 157     Radix = octal;
 158   else if (R == "d")
 159     Radix = decimal;
 160   else if (R == "x")
 161     Radix = hexadecimal;
 162   else
 163     reportCmdLineError("--radix value should be one of: '' (no offset), 'o' "
 164                        "(octal), 'd' (decimal), 'x' (hexadecimal)");
 165
 166   if (MinLength == 0) {
 167     errs() << "invalid minimum string length 0\n";
 168     return EXIT_FAILURE;
 169   }
 170
 171   std::vector<std::string> InputFileNames = Args.getAllArgValues(OPT_INPUT);
 172   if (InputFileNames.empty())
 173     InputFileNames.push_back("-");
 174
 175   for (const auto &File : InputFileNames) {
 176     ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
 177         MemoryBuffer::getFileOrSTDIN(File);
 178     if (std::error_code EC = Buffer.getError())
 179       errs() << File << ": " << EC.message() << '\n';
 180     else
 181       strings(llvm::outs(), File == "-" ? "{standard input}" : File,
 182               Buffer.get()->getMemBufferRef().getBuffer());
 183   }
 184
 185   return EXIT_SUCCESS;
 186 }