fmt/test/fuzzing/named_arg.cpp
2020-10-11 08:07:52 -07:00

116 lines
2.6 KiB
C++

// Copyright (c) 2019, Paul Dreik
// For the license information refer to format.h.
#include <cstdint>
#include <type_traits>
#include <vector>
#include <fmt/chrono.h>
#include "fuzzer_common.h"
template <typename Item1>
void invoke_fmt(const uint8_t* data, size_t size, unsigned int argsize) {
static_assert(sizeof(Item1) <= fmt_fuzzer::nfixed, "nfixed too small");
if (size <= fmt_fuzzer::nfixed) return;
const Item1 item1 = fmt_fuzzer::assignFromBuf<Item1>(data);
data += fmt_fuzzer::nfixed;
size -= fmt_fuzzer::nfixed;
// How many chars should be used for the argument name?
if (argsize <= 0 || argsize >= size) return;
#if FMT_FUZZ_SEPARATE_ALLOCATION
std::vector<char> argnamebuffer(argsize + 1);
std::memcpy(argnamebuffer.data(), data, argsize);
auto argname = argnamebuffer.data();
#else
auto argname = fmt_fuzzer::as_chars(data);
#endif
data += argsize;
size -= argsize;
#if FMT_FUZZ_SEPARATE_ALLOCATION
std::vector<char> fmtstringbuffer(size);
std::memcpy(fmtstringbuffer.data(), data, size);
auto format_str = fmt::string_view(fmtstringbuffer.data(), size);
#else
auto format_str = fmt::string_view(fmt_fuzzer::as_chars(data), size);
#endif
#if FMT_FUZZ_FORMAT_TO_STRING
std::string message = fmt::format(format_str, fmt::arg(argname, item1));
#else
fmt::memory_buffer out;
fmt::format_to(out, format_str, fmt::arg(argname, item1));
#endif
}
// For dynamic dispatching to an explicit instantiation.
template <typename Callback> void invoke(int index, Callback callback) {
switch (index) {
case 0:
callback(bool());
break;
case 1:
callback(char());
break;
case 2:
using sc = signed char;
callback(sc());
break;
case 3:
using uc = unsigned char;
callback(uc());
break;
case 4:
callback(short());
break;
case 5:
using us = unsigned short;
callback(us());
break;
case 6:
callback(int());
break;
case 7:
callback(unsigned());
break;
case 8:
callback(long());
break;
case 9:
using ul = unsigned long;
callback(ul());
break;
case 10:
callback(float());
break;
case 11:
callback(double());
break;
case 12:
using LD = long double;
callback(LD());
break;
}
}
extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
if (size <= 3) return 0;
// Switch types depending on the first byte of the input.
const auto first = data[0] & 0x0F;
const unsigned second = (data[0] & 0xF0) >> 4;
data++;
size--;
try {
invoke(first, [=](auto param1) {
invoke_fmt<decltype(param1)>(data, size, second);
});
} catch (std::exception&) {
}
return 0;
}