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Diffstat (limited to '')
-rw-r--r-- | src/fmt/test/fuzzing/float.cc | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/src/fmt/test/fuzzing/float.cc b/src/fmt/test/fuzzing/float.cc new file mode 100644 index 000000000..d4c9e4f57 --- /dev/null +++ b/src/fmt/test/fuzzing/float.cc @@ -0,0 +1,39 @@ +// A fuzzer for floating-point formatter. +// For the license information refer to format.h. + +#include <fmt/format.h> + +#include <cstdint> +#include <cstdlib> +#include <limits> +#include <stdexcept> + +#include "fuzzer-common.h" + +void check_round_trip(fmt::string_view format_str, double value) { + auto buffer = fmt::memory_buffer(); + fmt::format_to(std::back_inserter(buffer), format_str, value); + + if (std::isnan(value)) { + auto nan = std::signbit(value) ? "-nan" : "nan"; + if (fmt::string_view(buffer.data(), buffer.size()) != nan) + throw std::runtime_error("round trip failure"); + return; + } + + buffer.push_back('\0'); + char* ptr = nullptr; + if (std::strtod(buffer.data(), &ptr) != value) + throw std::runtime_error("round trip failure"); + if (ptr + 1 != buffer.end()) throw std::runtime_error("unparsed output"); +} + +extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) { + if (size <= sizeof(double) || !std::numeric_limits<double>::is_iec559) + return 0; + check_round_trip("{}", assign_from_buf<double>(data)); + // A larger than necessary precision is used to trigger the fallback + // formatter. + check_round_trip("{:.50g}", assign_from_buf<double>(data)); + return 0; +} |