// Copyright 2018 Google Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//      http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

//

////////////////////////////////////////////////////////////////////////////////

#include "fuzz.h"

#include "webp/decode.h"

int LLVMFuzzerTestOneInput(const uint8_t* const data, size_t size) {

  int w, h;

  if (!WebPGetInfo(data, size, &w, &h)) return 0;

  if ((size_t)w * h > kFuzzPxLimit) return 0;

  const uint8_t value = FuzzHash(data, size);

  uint8_t* buf = NULL;

  // For *Into functions, which decode into an external buffer, an

  // intentionally too small buffer can be given with low probability.

  if (value < 0x16) {

    buf = WebPDecodeRGBA(data, size, &w, &h);

  } else if (value < 0x2b) {

    buf = WebPDecodeARGB(data, size, &w, &h);

  } else if (value < 0x40) {

    buf = WebPDecodeBGRA(data, size, &w, &h);

  } else if (value < 0x55) {

    buf = WebPDecodeRGB(data, size, &w, &h);

  } else if (value < 0x6a) {

    buf = WebPDecodeBGR(data, size, &w, &h);

  } else if (value < 0x7f) {

    uint8_t *u, *v;

    int stride, uv_stride;

    buf = WebPDecodeYUV(data, size, &w, &h, &u, &v, &stride, &uv_stride);

  } else if (value < 0xe8) {

    const int stride = (value < 0xbe ? 4 : 3) * w;

    size_t buf_size = stride * h;

    if (value % 0x10 == 0) buf_size--;

    uint8_t* const ext_buf = (uint8_t*)malloc(buf_size);

    if (value < 0x94) {

      WebPDecodeRGBAInto(data, size, ext_buf, buf_size, stride);

    } else if (value < 0xa9) {

      WebPDecodeARGBInto(data, size, ext_buf, buf_size, stride);

    } else if (value < 0xbe) {

      WebPDecodeBGRAInto(data, size, ext_buf, buf_size, stride);

    } else if (value < 0xd3) {

      WebPDecodeRGBInto(data, size, ext_buf, buf_size, stride);

    } else {

      WebPDecodeBGRInto(data, size, ext_buf, buf_size, stride);

    }

    free(ext_buf);

  } else {

    size_t luma_size = w * h;

    const int uv_stride = (w + 1) / 2;

    size_t u_size = uv_stride * (h + 1) / 2;

    size_t v_size = uv_stride * (h + 1) / 2;

    if (value % 0x10 == 0) {

      if (size & 1) luma_size--;

      if (size & 2) u_size--;

      if (size & 4) v_size--;

    }

    uint8_t* const luma_buf = (uint8_t*)malloc(luma_size);

    uint8_t* const u_buf = (uint8_t*)malloc(u_size);

    uint8_t* const v_buf = (uint8_t*)malloc(v_size);

    WebPDecodeYUVInto(data, size, luma_buf, luma_size, w /* luma_stride */,

                      u_buf, u_size, uv_stride, v_buf, v_size, uv_stride);

    free(luma_buf);

    free(u_buf);

    free(v_buf);

  }

  if (buf) WebPFree(buf);

  return 0;

}