llvm/libc/fuzzing/stdlib/strtointeger_differential_fuzz.cpp

//===-- strtointeger_differential_fuzz.cpp --------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// Fuzzing test for llvm-libc atof implementation.
///
//===----------------------------------------------------------------------===//
#include "src/stdlib/atoi.h"
#include "src/stdlib/atol.h"
#include "src/stdlib/atoll.h"
#include "src/stdlib/strtol.h"
#include "src/stdlib/strtoll.h"
#include "src/stdlib/strtoul.h"
#include "src/stdlib/strtoull.h"
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>

#include "fuzzing/stdlib/StringParserOutputDiff.h"

// This list contains (almost) all character that can possibly be accepted by a
// string to integer conversion. Those are: space, tab, +/- signs, any digit,
// and any letter. Technically there are some space characters accepted by
// isspace that aren't in this list, but since space characters are just skipped
// over anyways I'm not really worried.
[[maybe_unused]] constexpr char VALID_CHARS[] = …;

// This takes the randomized bytes in data and interprets the first byte as the
// base for the string to integer conversion and the rest of them as a string to
// be passed to the string to integer conversion.
// If the CLEANER_INPUT flag is set, the string is modified so that it's only
// made of characters that the string to integer functions could accept. This is
// because every other character is effectively identical, and will be treated
// as the end of the integer. For the fully randomized string this gives a
// greater than 50% chance for each character to end the string, making the odds
// of getting long numbers very low.
extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { … }