freebsd-nq/contrib/compiler-rt/lib/fuzzer/FuzzerDataFlowTrace.cpp
Dimitry Andric 678769a9fc Add compiler-rt's libFuzzer, not connected to buildworld yet.
For now, the libraries can be built and installed using:

cd /usr/src/lib/libclang_rt/fuzzer && \
  make obj && \
  make depend && \
  make && \
  sudo make install
cd /usr/src/lib/libclang_rt/fuzzer_no_main && \
  make obj && \
  make depend && \
  make && \
  sudo make install

See https://llvm.org/docs/LibFuzzer.html for more information.
2018-09-29 15:17:17 +00:00

92 lines
3.1 KiB
C++

//===- FuzzerDataFlowTrace.cpp - DataFlowTrace ---*- C++ -* ===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// fuzzer::DataFlowTrace
//===----------------------------------------------------------------------===//
#include "FuzzerDataFlowTrace.h"
#include "FuzzerIO.h"
#include <cstdlib>
#include <fstream>
#include <string>
#include <vector>
namespace fuzzer {
void DataFlowTrace::Init(const std::string &DirPath,
const std::string &FocusFunction) {
if (DirPath.empty()) return;
const char *kFunctionsTxt = "functions.txt";
Printf("INFO: DataFlowTrace: reading from '%s'\n", DirPath.c_str());
Vector<SizedFile> Files;
GetSizedFilesFromDir(DirPath, &Files);
std::string L;
// Read functions.txt
std::ifstream IF(DirPlusFile(DirPath, kFunctionsTxt));
size_t FocusFuncIdx = SIZE_MAX;
size_t NumFunctions = 0;
while (std::getline(IF, L, '\n')) {
NumFunctions++;
if (FocusFunction == L)
FocusFuncIdx = NumFunctions - 1;
}
if (!NumFunctions || FocusFuncIdx == SIZE_MAX || Files.size() <= 1)
return;
// Read traces.
size_t NumTraceFiles = 0;
size_t NumTracesWithFocusFunction = 0;
for (auto &SF : Files) {
auto Name = Basename(SF.File);
if (Name == kFunctionsTxt) continue;
auto ParseError = [&](const char *Err) {
Printf("DataFlowTrace: parse error: %s\n File: %s\n Line: %s\n", Err,
Name.c_str(), L.c_str());
};
NumTraceFiles++;
// Printf("=== %s\n", Name.c_str());
std::ifstream IF(SF.File);
while (std::getline(IF, L, '\n')) {
size_t SpacePos = L.find(' ');
if (SpacePos == std::string::npos)
return ParseError("no space in the trace line");
if (L.empty() || L[0] != 'F')
return ParseError("the trace line doesn't start with 'F'");
size_t N = std::atol(L.c_str() + 1);
if (N >= NumFunctions)
return ParseError("N is greater than the number of functions");
if (N == FocusFuncIdx) {
NumTracesWithFocusFunction++;
const char *Beg = L.c_str() + SpacePos + 1;
const char *End = L.c_str() + L.size();
assert(Beg < End);
size_t Len = End - Beg;
Vector<uint8_t> V(Len);
for (size_t I = 0; I < Len; I++) {
if (Beg[I] != '0' && Beg[I] != '1')
ParseError("the trace should contain only 0 or 1");
V[I] = Beg[I] == '1';
}
Traces[Name] = V;
// Print just a few small traces.
if (NumTracesWithFocusFunction <= 3 && Len <= 16)
Printf("%s => |%s|\n", Name.c_str(), L.c_str() + SpacePos + 1);
break; // No need to parse the following lines.
}
}
}
assert(NumTraceFiles == Files.size() - 1);
Printf("INFO: DataFlowTrace: %zd trace files, %zd functions, "
"%zd traces with focus function\n",
NumTraceFiles, NumFunctions, NumTracesWithFocusFunction);
}
} // namespace fuzzer