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"
23 // * don't dump the coverage to disk.
24 // * enable coverage by default.
25 extern "C" const char *__asan_default_options() {
26 return "coverage_pcs=0:coverage=1";
30 struct FlagDescription {
32 const char *Description;
38 #define FUZZER_FLAG(Type, Name, Default, Description) Type Name;
39 #include "FuzzerFlags.def"
43 static FlagDescription FlagDescriptions [] {
44 #define FUZZER_FLAG(Type, Name, Default, Description) {#Name, Description, Default, &Flags.Name},
45 #include "FuzzerFlags.def"
49 static const size_t kNumFlags =
50 sizeof(FlagDescriptions) / sizeof(FlagDescriptions[0]);
52 static std::vector<std::string> inputs;
53 static const char *ProgName;
55 static void PrintHelp() {
56 std::cerr << "Usage: " << ProgName
57 << " [-flag1=val1 [-flag2=val2 ...] ] [dir1 [dir2 ...] ]\n";
58 std::cerr << "\nFlags: (strictly in form -flag=value)\n";
59 size_t MaxFlagLen = 0;
60 for (size_t F = 0; F < kNumFlags; F++)
61 MaxFlagLen = std::max(strlen(FlagDescriptions[F].Name), MaxFlagLen);
63 for (size_t F = 0; F < kNumFlags; F++) {
64 const auto &D = FlagDescriptions[F];
65 std::cerr << " " << D.Name;
66 for (size_t i = 0, n = MaxFlagLen - strlen(D.Name); i < n; i++)
69 std::cerr << D.Default << "\t" << D.Description << "\n";
73 static const char *FlagValue(const char *Param, const char *Name) {
74 size_t Len = strlen(Name);
75 if (Param[0] == '-' && strstr(Param + 1, Name) == Param + 1 &&
76 Param[Len + 1] == '=')
77 return &Param[Len + 2];
81 static bool ParseOneFlag(const char *Param) {
82 if (Param[0] != '-') return false;
83 for (size_t F = 0; F < kNumFlags; F++) {
84 const char *Name = FlagDescriptions[F].Name;
85 const char *Str = FlagValue(Param, Name);
87 int Val = std::stol(Str);
88 *FlagDescriptions[F].Flag = Val;
89 if (Flags.verbosity >= 2)
90 std::cerr << "Flag: " << Name << " " << Val << "\n";
98 // We don't use any library to minimize dependencies.
99 static void ParseFlags(int argc, char **argv) {
100 for (size_t F = 0; F < kNumFlags; F++)
101 *FlagDescriptions[F].Flag = FlagDescriptions[F].Default;
102 for (int A = 1; A < argc; A++) {
103 if (ParseOneFlag(argv[A])) continue;
104 inputs.push_back(argv[A]);
108 static void WorkerThread(const std::string &Cmd, std::atomic<int> *Counter,
109 int NumJobs, std::atomic<bool> *HasErrors) {
110 static std::mutex CerrMutex;
112 int C = (*Counter)++;
113 if (C >= NumJobs) break;
114 std::string Log = "fuzz-" + std::to_string(C) + ".log";
115 std::string ToRun = Cmd + " > " + Log + " 2>&1\n";
118 int ExitCode = system(ToRun.c_str());
121 std::lock_guard<std::mutex> Lock(CerrMutex);
122 std::cerr << "================== Job " << C
123 << " exited with exit code " << ExitCode
124 << " =================\n";
125 fuzzer::CopyFileToErr(Log);
129 static int RunInMultipleProcesses(int argc, char **argv, int NumWorkers,
131 std::atomic<int> Counter(0);
132 std::atomic<bool> HasErrors(false);
134 for (int i = 0; i < argc; i++) {
135 if (FlagValue(argv[i], "jobs") || FlagValue(argv[i], "workers")) continue;
139 std::vector<std::thread> V;
140 for (int i = 0; i < NumWorkers; i++)
141 V.push_back(std::thread(WorkerThread, Cmd, &Counter, NumJobs, &HasErrors));
144 return HasErrors ? 1 : 0;
147 int main(int argc, char **argv) {
148 using namespace fuzzer;
151 ParseFlags(argc, argv);
157 if (Flags.workers > 0 && Flags.jobs > 0)
158 return RunInMultipleProcesses(argc, argv, Flags.workers, Flags.jobs);
160 Fuzzer::FuzzingOptions Options;
161 Options.Verbosity = Flags.verbosity;
162 Options.MaxLen = Flags.max_len;
163 Options.DoCrossOver = Flags.cross_over;
164 Options.MutateDepth = Flags.mutate_depth;
165 Options.ExitOnFirst = Flags.exit_on_first;
166 Options.UseFullCoverageSet = Flags.use_full_coverage_set;
168 Options.OutputCorpus = inputs[0];
171 unsigned seed = Flags.seed;
174 seed = time(0) * 10000 + getpid();
176 std::cerr << "Seed: " << seed << "\n";
180 if (Flags.timeout > 0)
181 SetTimer(Flags.timeout);
183 for (auto &inp : inputs)
186 if (F.CorpusSize() == 0)
187 F.AddToCorpus(Unit()); // Can't fuzz empty corpus, so add an empty input.
188 F.ShuffleAndMinimize();
189 if (Flags.save_minimized_corpus)
191 F.Loop(Flags.iterations < 0 ? INT_MAX : Flags.iterations);
193 std::cerr << "Done\n";