/* Copyright 2025 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 <stdint.h>

#include <stdio.h>

#include <stdlib.h>

#include "cJSON.h"

#include "loader.h"

#include "fuzz_header.h"

int LLVMFuzzerInitialize(int *argc, char ***argv) {

  setenv("HOME", "/tmp", 1);

  system("mkdir -p $HOME/.local/share/vulkan/implicit_layer.d");

  system("mkdir -p $HOME/.local/share/vulkan/loader_settings.d");

  system("mkdir -p $HOME/.local/share/vulkan/icd.d");

  return 0;

}

/*

 * Create config files for given path and data.

 */

int create_config_file(const char* config_path, const char* config_filename, const uint8_t* data, size_t size) {

  char filename[512];

  char path[256];

  // char command[256];

  sprintf(path, "%s/%s", getenv("HOME"), config_path);

  //sprintf(command, "mkdir -p %s", path);

  //system(command);

  sprintf(filename, "%s/%s", path, config_filename);

  FILE *fp = fopen(filename, "wb");

  if (!fp) {

    return 1;

  }

  fwrite(data, size, 1, fp);

  fclose(fp);

  return 0;

}

/*

 * Remove config file

 */

void remove_config_file(const char* config_path, const char* config_filename) {

  char filename[512];

  sprintf(filename, "%s/%s/%s", getenv("HOME"), config_path, config_filename);

  unlink(filename);

}

/*

 * Targets the instance creation.

 */

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

  if (size < 3*sizeof(size_t)) {

    return 0;

  }

  // Split the loaders into two different parts so the files

  // are independently seeded with fuzz data.

  size_t first_size = (*(size_t*)data) % 40000;

  size_t second_size = (*(size_t*)(data + sizeof(size_t))) % 40000;

  size_t third_size = (*(size_t*)(data + 2*sizeof(size_t))) % 40000;

  data += 3*sizeof(size_t); // Move past the first two integers

  size -= 3*sizeof(size_t); // Adjust size to account for the first two integers

  size_t total_size_needed = first_size + second_size + third_size;

  if (size <= total_size_needed) {

    return 0;

  }

  int result = create_config_file(".local/share/vulkan/implicit_layer.d", "complex_layer.json", data, first_size);

  if (result) {

    return 0;

  }

  data += first_size;

  size -= first_size;

  result = create_config_file(".local/share/vulkan/loader_settings.d", "vk_loader_settings.json", data, second_size);

  if (result) {

    return 0;

  }

  data += second_size;

  size -= second_size;

  result = create_config_file(".local/share/vulkan/loader_settings.d", "icd_test.json", data, third_size);

  if (result) {

    return 0;

  }

  data += third_size;

  size -= third_size;

  fuzz_init(data, size);

  setenv("VK_LOADER_LAYERS_ENABLE", "all", 1);

  VkInstance inst = {0};

  char *instance_layers[] = {

    "VK_LAYER_KHRONOS_validation",

    "VK_LAYER_test_layer_1",

    "VK_LAYER_test_layer_2"

  };

  const VkApplicationInfo app = {

      .sType = VK_STRUCTURE_TYPE_APPLICATION_INFO,

      .pNext = NULL,

      .pApplicationName = "TEST_APP",

      .applicationVersion = 0,

      .pEngineName = "TEST_ENGINE",

      .engineVersion = 0,

      .apiVersion = VK_API_VERSION_1_0,

  };

  VkInstanceCreateInfo inst_info = {

      .sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO,

      .pNext = NULL,

      .pApplicationInfo = &app,

      .enabledLayerCount = 1,

      .ppEnabledLayerNames = (const char *const *)instance_layers,

      .enabledExtensionCount = 0,

      .ppEnabledExtensionNames = NULL,

  };

  VkResult err = vkCreateInstance(&inst_info, NULL, &inst);

  if (err != VK_SUCCESS) {

    goto out;

  }

  else {

  }

  vkDestroyInstance(inst, NULL);

out:

  // Clean up config files

  remove_config_file(".local/share/vulkan/implicit_layer.d", "complex_layer.json");

  remove_config_file(".local/share/vulkan/loader_settings.d", "vk_loader_settings.json");

  remove_config_file(".local/share/vulkan/icd.d", "icd_test.json");

  fuzz_cleanup();

  return 0;

}