xref: /llvm-project/llvm/tools/llvm-strings/llvm-strings.cpp (revision e953ae5bbc313fd0cc980ce021d487e5b5199ea4)
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)                                                    \
43   static constexpr StringLiteral NAME##_init[] = VALUE;                        \
44   static constexpr ArrayRef<StringLiteral> NAME(NAME##_init,                   \
45                                                 std::size(NAME##_init) - 1);
46 #include "Opts.inc"
47 #undef PREFIX
48 
49 static constexpr opt::OptTable::Info InfoTable[] = {
50 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
51                HELPTEXT, METAVAR, VALUES)                                      \
52   {                                                                            \
53       PREFIX,      NAME,      HELPTEXT,                                        \
54       METAVAR,     OPT_##ID,  opt::Option::KIND##Class,                        \
55       PARAM,       FLAGS,     OPT_##GROUP,                                     \
56       OPT_##ALIAS, ALIASARGS, VALUES},
57 #include "Opts.inc"
58 #undef OPTION
59 };
60 
61 class StringsOptTable : public opt::OptTable {
62 public:
63   StringsOptTable() : OptTable(InfoTable) { setGroupedShortOptions(true); }
64 };
65 } // namespace
66 
67 static StringRef ToolName;
68 
69 static cl::list<std::string> InputFileNames(cl::Positional,
70                                             cl::desc("<input object files>"));
71 
72 static int MinLength = 4;
73 static bool PrintFileName;
74 
75 enum radix { none, octal, hexadecimal, decimal };
76 static radix Radix;
77 
78 [[noreturn]] static void reportCmdLineError(const Twine &Message) {
79   WithColor::error(errs(), ToolName) << Message << "\n";
80   exit(1);
81 }
82 
83 template <typename T>
84 static void parseIntArg(const opt::InputArgList &Args, int ID, T &Value) {
85   if (const opt::Arg *A = Args.getLastArg(ID)) {
86     StringRef V(A->getValue());
87     if (!llvm::to_integer(V, Value, 0) || Value <= 0)
88       reportCmdLineError("expected a positive integer, but got '" + V + "'");
89   }
90 }
91 
92 static void strings(raw_ostream &OS, StringRef FileName, StringRef Contents) {
93   auto print = [&OS, FileName](unsigned Offset, StringRef L) {
94     if (L.size() < static_cast<size_t>(MinLength))
95       return;
96     if (PrintFileName)
97       OS << FileName << ": ";
98     switch (Radix) {
99     case none:
100       break;
101     case octal:
102       OS << format("%7o ", Offset);
103       break;
104     case hexadecimal:
105       OS << format("%7x ", Offset);
106       break;
107     case decimal:
108       OS << format("%7u ", Offset);
109       break;
110     }
111     OS << L << '\n';
112   };
113 
114   const char *B = Contents.begin();
115   const char *P = nullptr, *E = nullptr, *S = nullptr;
116   for (P = Contents.begin(), E = Contents.end(); P < E; ++P) {
117     if (isPrint(*P) || *P == '\t') {
118       if (S == nullptr)
119         S = P;
120     } else if (S) {
121       print(S - B, StringRef(S, P - S));
122       S = nullptr;
123     }
124   }
125   if (S)
126     print(S - B, StringRef(S, E - S));
127 }
128 
129 int main(int argc, char **argv) {
130   InitLLVM X(argc, argv);
131   BumpPtrAllocator A;
132   StringSaver Saver(A);
133   StringsOptTable Tbl;
134   ToolName = argv[0];
135   opt::InputArgList Args =
136       Tbl.parseArgs(argc, argv, OPT_UNKNOWN, Saver,
137                     [&](StringRef Msg) { reportCmdLineError(Msg); });
138   if (Args.hasArg(OPT_help)) {
139     Tbl.printHelp(
140         outs(),
141         (Twine(ToolName) + " [options] <input object files>").str().c_str(),
142         "llvm string dumper");
143     // TODO Replace this with OptTable API once it adds extrahelp support.
144     outs() << "\nPass @FILE as argument to read options from FILE.\n";
145     return 0;
146   }
147   if (Args.hasArg(OPT_version)) {
148     outs() << ToolName << '\n';
149     cl::PrintVersionMessage();
150     return 0;
151   }
152 
153   parseIntArg(Args, OPT_bytes_EQ, MinLength);
154   PrintFileName = Args.hasArg(OPT_print_file_name);
155   StringRef R = Args.getLastArgValue(OPT_radix_EQ);
156   if (R.empty())
157     Radix = none;
158   else if (R == "o")
159     Radix = octal;
160   else if (R == "d")
161     Radix = decimal;
162   else if (R == "x")
163     Radix = hexadecimal;
164   else
165     reportCmdLineError("--radix value should be one of: '' (no offset), 'o' "
166                        "(octal), 'd' (decimal), 'x' (hexadecimal)");
167 
168   if (MinLength == 0) {
169     errs() << "invalid minimum string length 0\n";
170     return EXIT_FAILURE;
171   }
172 
173   std::vector<std::string> InputFileNames = Args.getAllArgValues(OPT_INPUT);
174   if (InputFileNames.empty())
175     InputFileNames.push_back("-");
176 
177   for (const auto &File : InputFileNames) {
178     ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
179         MemoryBuffer::getFileOrSTDIN(File);
180     if (std::error_code EC = Buffer.getError())
181       errs() << File << ": " << EC.message() << '\n';
182     else
183       strings(llvm::outs(), File == "-" ? "{standard input}" : File,
184               Buffer.get()->getMemBufferRef().getBuffer());
185   }
186 
187   return EXIT_SUCCESS;
188 }
189