/*

# Copyright 2019 The Chromium OS Authors.

#

# 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 <base/gserrors.h>

#include <psi/iapi.h>

#include <limits.h>

#include <stdio.h>

#include <string.h>

#include <stdint.h>

static const unsigned char *g_data;

static size_t g_size;

int fuzz_gs_device(

  const unsigned char *buf,

  size_t size,

  int color_scheme,

  const char *device_target,

  const char *output_file,

  int do_interpolation

);

#define min(x, y) ((x) < (y) ? (x) : (y))

static int gs_stdin(void *inst, char *buf, int len)

{

  size_t to_copy = min(len, g_size);

  to_copy = min(INT_MAX, to_copy);

  memcpy(buf, g_data, to_copy);

  g_data += to_copy;

  g_size -= to_copy;

  return to_copy;

}

static int gs_stdnull(void *inst, const char *buf, int len)

{

  /* Just discard everything. */

  return len;

}

int gs_to_raster_fuzz(

  const unsigned char *buf,

  size_t size,

  int color_scheme

)

{

  return fuzz_gs_device(buf, size, color_scheme, "cups", "/dev/null", 0);

}

int fuzz_gs_device(

  const unsigned char *buf,

  size_t size,

  int color_scheme,

  const char *device_target,

  const char *output_file,

  int do_interpolation

)

{

  int ret;

  void *gs = NULL;

  char color_space[50];

  char gs_device[50];

  char gs_o[100];

  char opt_interpolation[50];

  /*

   * We are expecting color_scheme to be in the [0:62] interval.

   * This corresponds to the color schemes defined here:

   * https://github.com/ArtifexSoftware/ghostpdl/blob/8c97d5adce0040ac38a1fb4d7954499c65f582ff/cups/libs/cups/raster.h#L102

   */

  sprintf(color_space, "-dcupsColorSpace=%d", color_scheme);

  sprintf(gs_device, "-sDEVICE=%s", device_target);

  sprintf(gs_o, "-sOutputFile=%s", output_file);

  if (do_interpolation) {

    sprintf(opt_interpolation, "-dDOINTERPOLATE");

  }

  else {

    sprintf(opt_interpolation, "-dNOINTERPOLATE");

  }

  /* Mostly stolen from cups-filters gstoraster. */

  char *args[] = {

    "gs",

    "-K1048576",

    "-r200x200",

    "-sBandListStorage=memory",

    "-dMaxBitmap=0",

    "-dBufferSpace=450k",

    "-dMediaPosition=1",

    color_space,

    "-dQUIET",

    "-dSAFER",

    "-dNOPAUSE",

    "-dBATCH",

    opt_interpolation,

    "-dNOMEDIAATTRS",

    "-sstdout=%%stderr",

    gs_o,

    gs_device,

    "-_",

  };

  int argc = sizeof(args) / sizeof(args[0]);

  /* Stash buffers globally, for gs_stdin(). */

  g_data = buf;

  g_size = size;

  ret = gsapi_new_instance(&gs, NULL);

  if (ret < 0) {

    fprintf(stderr, "gsapi_new_instance: error %d\n", ret);

    return ret;

  }

  gsapi_set_stdio(gs, gs_stdin, gs_stdnull, gs_stdnull);

  ret = gsapi_set_arg_encoding(gs, GS_ARG_ENCODING_UTF8);

  if (ret < 0) {

    fprintf(stderr, "gsapi_set_arg_encoding: error %d\n", ret);

    gsapi_delete_instance(gs);

    return ret;

  }

  ret = gsapi_init_with_args(gs, argc, args);

  if (ret && ret != gs_error_Quit)

    /* Just keep going, to cleanup. */

    fprintf(stderr, "gsapi_init_with_args: error %d\n", ret);

  ret = gsapi_exit(gs);

  if (ret < 0 && ret != gs_error_Quit) {

    fprintf(stderr, "gsapi_exit: error %d\n", ret);

    return ret;

  }

  gsapi_delete_instance(gs);

  return 0;

}