zstd/tests/fuzz/fuzz_data_producer.c

86 lines
2.4 KiB
C

/*
* Copyright (c) 2016-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under both the BSD-style license (found in the
* LICENSE file in the root directory of this source tree) and the GPLv2 (found
* in the COPYING file in the root directory of this source tree).
*/
#include "fuzz_data_producer.h"
struct FUZZ_dataProducer_s{
const uint8_t *data;
size_t size;
};
FUZZ_dataProducer_t *FUZZ_dataProducer_create(const uint8_t *data, size_t size) {
FUZZ_dataProducer_t *producer = malloc(sizeof(FUZZ_dataProducer_t));
FUZZ_ASSERT(producer != NULL);
producer->data = data;
producer->size = size;
return producer;
}
void FUZZ_dataProducer_free(FUZZ_dataProducer_t *producer) { free(producer); }
uint32_t FUZZ_dataProducer_uint32Range(FUZZ_dataProducer_t *producer, uint32_t min,
uint32_t max) {
FUZZ_ASSERT(min <= max);
uint32_t range = max - min;
uint32_t rolling = range;
uint32_t result = 0;
while (rolling > 0 && producer->size > 0) {
uint8_t next = *(producer->data + producer->size - 1);
producer->size -= 1;
result = (result << 8) | next;
rolling >>= 8;
}
if (range == 0xffffffff) {
return result;
}
return min + result % (range + 1);
}
uint32_t FUZZ_dataProducer_uint32(FUZZ_dataProducer_t *producer) {
return FUZZ_dataProducer_uint32Range(producer, 0, 0xffffffff);
}
int32_t FUZZ_dataProducer_int32Range(FUZZ_dataProducer_t *producer,
int32_t min, int32_t max)
{
FUZZ_ASSERT(min <= max);
if (min < 0)
return (int)FUZZ_dataProducer_uint32Range(producer, 0, max - min) + min;
return FUZZ_dataProducer_uint32Range(producer, min, max);
}
size_t FUZZ_dataProducer_remainingBytes(FUZZ_dataProducer_t *producer){
return producer->size;
}
size_t FUZZ_dataProducer_contract(FUZZ_dataProducer_t *producer, size_t newSize)
{
newSize = newSize > producer->size ? producer->size : newSize;
size_t remaining = producer->size - newSize;
producer->data = producer->data + remaining;
producer->size = newSize;
return remaining;
}
size_t FUZZ_dataProducer_reserveDataPrefix(FUZZ_dataProducer_t *producer)
{
size_t producerSliceSize = FUZZ_dataProducer_uint32Range(
producer, 0, producer->size);
return FUZZ_dataProducer_contract(producer, producerSliceSize);
}