1 //===- FuzzerMain.cpp - main() function and flags -------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 //===----------------------------------------------------------------------===//
12 #include "FuzzerInternal.h"
20 // * don't dump the coverage to disk.
21 // * enable coverage by default.
22 extern "C" const char *__asan_default_options() {
23 return "coverage_pcs=0:coverage=1";
27 struct FlagDescription {
29 const char *Description;
35 #define FUZZER_FLAG(Type, Name, Default, Description) Type Name;
36 #include "FuzzerFlags.def"
40 static FlagDescription FlagDescriptions [] {
41 #define FUZZER_FLAG(Type, Name, Default, Description) {#Name, Description, Default, &Flags.Name},
42 #include "FuzzerFlags.def"
46 static const size_t kNumFlags =
47 sizeof(FlagDescriptions) / sizeof(FlagDescriptions[0]);
49 static std::vector<std::string> inputs;
50 static const char *ProgName;
52 static void PrintHelp() {
53 std::cerr << "Usage: " << ProgName
54 << " [-flag1=val1 [-flag2=val2 ...] ] [dir1 [dir2 ...] ]\n";
55 std::cerr << "\nFlags: (strictly in form -flag=value)\n";
56 size_t MaxFlagLen = 0;
57 for (size_t F = 0; F < kNumFlags; F++)
58 MaxFlagLen = std::max(strlen(FlagDescriptions[F].Name), MaxFlagLen);
60 for (size_t F = 0; F < kNumFlags; F++) {
61 const auto &D = FlagDescriptions[F];
62 std::cerr << " " << D.Name;
63 for (size_t i = 0, n = MaxFlagLen - strlen(D.Name); i < n; i++)
66 std::cerr << D.Default << "\t" << D.Description << "\n";
70 static const char *FlagValue(const char *Param, const char *Name) {
71 size_t Len = strlen(Name);
72 if (Param[0] == '-' && strstr(Param + 1, Name) == Param + 1 &&
73 Param[Len + 1] == '=')
74 return &Param[Len + 2];
78 static bool ParseOneFlag(const char *Param) {
79 if (Param[0] != '-') return false;
80 for (size_t F = 0; F < kNumFlags; F++) {
81 const char *Name = FlagDescriptions[F].Name;
82 const char *Str = FlagValue(Param, Name);
84 int Val = std::stol(Str);
85 *FlagDescriptions[F].Flag = Val;
86 if (Flags.verbosity >= 2)
87 std::cerr << "Flag: " << Name << " " << Val << "\n";
95 // We don't use any library to minimize dependencies.
96 static void ParseFlags(int argc, char **argv) {
97 for (size_t F = 0; F < kNumFlags; F++)
98 *FlagDescriptions[F].Flag = FlagDescriptions[F].Default;
99 for (int A = 1; A < argc; A++) {
100 if (ParseOneFlag(argv[A])) continue;
101 inputs.push_back(argv[A]);
105 int main(int argc, char **argv) {
106 using namespace fuzzer;
109 ParseFlags(argc, argv);
114 Fuzzer::FuzzingOptions Options;
115 Options.Verbosity = Flags.verbosity;
116 Options.MaxLen = Flags.max_len;
117 Options.DoCrossOver = Flags.cross_over;
118 Options.MutateDepth = Flags.mutate_depth;
119 Options.ExitOnFirst = Flags.exit_on_first;
121 Options.OutputCorpus = inputs[0];
124 unsigned seed = Flags.seed;
127 seed = time(0) * 10000 + getpid();
129 std::cerr << "Seed: " << seed << "\n";
133 if (Flags.timeout > 0)
134 SetTimer(Flags.timeout);
136 for (auto &inp : inputs)
139 if (F.CorpusSize() == 0)
140 F.AddToCorpus(Unit()); // Can't fuzz empty corpus, so add an empty input.
141 F.ShuffleAndMinimize();
142 if (Flags.save_minimized_corpus)
144 F.Loop(Flags.iterations < 0 ? INT_MAX : Flags.iterations);
146 std::cerr << "Done\n";