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 static 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:
StringsOptTable()60 StringsOptTable() : OptTable(InfoTable) { setGroupedShortOptions(true); }
61 };
62 } // namespace
63
64 const char ToolName[] = "llvm-strings";
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
reportCmdLineError(const Twine & Message)76 LLVM_ATTRIBUTE_NORETURN static void reportCmdLineError(const Twine &Message) {
77 WithColor::error(errs(), ToolName) << Message << "\n";
78 exit(1);
79 }
80
81 template <typename T>
parseIntArg(const opt::InputArgList & Args,int ID,T & Value)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
strings(raw_ostream & OS,StringRef FileName,StringRef Contents)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
main(int argc,char ** argv)127 int main(int argc, char **argv) {
128 InitLLVM X(argc, argv);
129 BumpPtrAllocator A;
130 StringSaver Saver(A);
131 StringsOptTable Tbl;
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);
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 }
186