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 } 121