/* Copyright 2021 Google LLC
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 "dwarf.h"
#include "libdwarf.h"
#include <fcntl.h> /* open() O_RDONLY O_BINARY */
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#ifndef O_BINARY
#define O_BINARY 0
#endif

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  char filename[256];

#ifdef DWREGRESSIONTEMP
  /*  Under msys2, the /tmp/ results in an open fail,
      so we discard the /tmp/ here */
  sprintf(filename, "junklibfuzzer.%d", getpid());
#else
  sprintf(filename, "/tmp/libfuzzer.%d", getpid());
#endif
  FILE *fp = fopen(filename, "wb");
  if (!fp) {
    printf("FAIL libfuzzer cannot open temp as writeable %s\n",
        filename);
    return 0;
  }
  fwrite(data, size, 1, fp);
  fclose(fp);

  Dwarf_Error *errp = 0;
  Dwarf_Debug dbg = 0;
  int res = 0;
  int chosengroup = DW_GROUPNUMBER_ANY;
  Dwarf_Error error = 0;
  Dwarf_Unsigned section_count = 0;
  Dwarf_Unsigned group_count = 0;
  Dwarf_Unsigned selected_group = 0;
  Dwarf_Unsigned map_entry_count = 0;
  Dwarf_Unsigned *group_numbers_array = 0;
  Dwarf_Unsigned *sec_numbers_array = 0;
  const char **sec_names_array = 0;

  int run = dwarf_init_path(filename, 0, 0, chosengroup, 0, 0, &dbg, errp);
  if (run != -1) {
    if (run == DW_DLV_ERROR) {
      dwarf_finish(dbg);
      unlink(filename);
      return 0;
    }
    if (run == DW_DLV_NO_ENTRY) {
      dwarf_finish(dbg);
      unlink(filename);
      return 0;
    }
    res = dwarf_sec_group_sizes(dbg, &section_count, &group_count,
                                &selected_group, &map_entry_count, errp);
    if (res != DW_DLV_OK) {
      dwarf_dealloc_error(dbg, error);
      error = 0;
      dwarf_finish(dbg);
      unlink(filename);
      close(run);
      return 0;
    }
    group_numbers_array =
        (Dwarf_Unsigned *)calloc(map_entry_count, sizeof(Dwarf_Unsigned));
    sec_numbers_array =
        (Dwarf_Unsigned *)calloc(map_entry_count, sizeof(Dwarf_Unsigned));
    sec_names_array =
        (const char **)calloc(map_entry_count, sizeof(const char *));
    res = dwarf_sec_group_map(dbg, map_entry_count, group_numbers_array,
                              sec_numbers_array, sec_names_array, &error);
    free(sec_names_array);
    free(sec_numbers_array);
    free(group_numbers_array);
    dwarf_dealloc_error(dbg, error);
  }
  dwarf_finish(dbg);
  unlink(filename);
  close(run);
  return 0;
}