1//===- FuzzerMerge.h - merging corpa ----------------------------*- C++ -* ===// 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// Merging Corpora. 9// 10// The task: 11// Take the existing corpus (possibly empty) and merge new inputs into 12// it so that only inputs with new coverage ('features') are added. 13// The process should tolerate the crashes, OOMs, leaks, etc. 14// 15// Algorithm: 16// The outer process collects the set of files and writes their names 17// into a temporary "control" file, then repeatedly launches the inner 18// process until all inputs are processed. 19// The outer process does not actually execute the target code. 20// 21// The inner process reads the control file and sees a) list of all the inputs 22// and b) the last processed input. Then it starts processing the inputs one 23// by one. Before processing every input it writes one line to control file: 24// STARTED INPUT_ID INPUT_SIZE 25// After processing an input it writes the following lines: 26// FT INPUT_ID Feature1 Feature2 Feature3 ... 27// COV INPUT_ID Coverage1 Coverage2 Coverage3 ... 28// If a crash happens while processing an input the last line in the control 29// file will be "STARTED INPUT_ID" and so the next process will know 30// where to resume. 31// 32// Once all inputs are processed by the inner process(es) the outer process 33// reads the control files and does the merge based entirely on the contents 34// of control file. 35// It uses a single pass greedy algorithm choosing first the smallest inputs 36// within the same size the inputs that have more new features. 37// 38//===----------------------------------------------------------------------===// 39 40#ifndef LLVM_FUZZER_MERGE_H 41#define LLVM_FUZZER_MERGE_H 42 43#include "FuzzerDefs.h" 44#include "FuzzerIO.h" 45 46#include <istream> 47#include <ostream> 48#include <set> 49#include <vector> 50 51namespace fuzzer { 52 53struct MergeFileInfo { 54 std::string Name; 55 size_t Size = 0; 56 std::vector<uint32_t> Features, Cov; 57}; 58 59struct Merger { 60 std::vector<MergeFileInfo> Files; 61 size_t NumFilesInFirstCorpus = 0; 62 size_t FirstNotProcessedFile = 0; 63 std::string LastFailure; 64 65 bool Parse(std::istream &IS, bool ParseCoverage); 66 bool Parse(const std::string &Str, bool ParseCoverage); 67 void ParseOrExit(std::istream &IS, bool ParseCoverage); 68 size_t Merge(const std::set<uint32_t> &InitialFeatures, 69 std::set<uint32_t> *NewFeatures, 70 const std::set<uint32_t> &InitialCov, std::set<uint32_t> *NewCov, 71 std::vector<std::string> *NewFiles); 72 size_t SetCoverMerge(const std::set<uint32_t> &InitialFeatures, 73 std::set<uint32_t> *NewFeatures, 74 const std::set<uint32_t> &InitialCov, 75 std::set<uint32_t> *NewCov, 76 std::vector<std::string> *NewFiles); 77 size_t ApproximateMemoryConsumption() const; 78 std::set<uint32_t> AllFeatures() const; 79}; 80 81void CrashResistantMerge(const std::vector<std::string> &Args, 82 const std::vector<SizedFile> &OldCorpus, 83 const std::vector<SizedFile> &NewCorpus, 84 std::vector<std::string> *NewFiles, 85 const std::set<uint32_t> &InitialFeatures, 86 std::set<uint32_t> *NewFeatures, 87 const std::set<uint32_t> &InitialCov, 88 std::set<uint32_t> *NewCov, const std::string &CFPath, 89 bool Verbose, bool IsSetCoverMerge); 90 91} // namespace fuzzer 92 93#endif // LLVM_FUZZER_MERGE_H 94