text: #include <sys/stat.h>
  #include <errno.h>
  #include <fcntl.h>
  #include <libgen.h>
  #include <unistd.h>
  #include <stdio.h>
  #include "test.h"
  
  // ============================================================================
  // Helper function
  // ============================================================================
  
  static int create_file(const char *file_path, mode_t mode) {
      int flags = O_RDONLY | O_CREAT | O_TRUNC;
      int fd;
  
      fd = open(file_path, flags, mode);
      if (fd < 0) {
          THROW_ERROR("failed to create a file");
      }
      close(fd);
      return 0;
  }
  
  static int remove_file(const char *file_path) {
      int ret;
  
      ret = unlink(file_path);
      if (ret < 0) {
          THROW_ERROR("failed to unlink the created file");
      }
      return 0;
  }
  
  // ============================================================================
  // Test cases for access
  // ============================================================================
  
  static int __test_access(const char *file_path) {
      if (access(file_path, F_OK) < 0) {
          THROW_ERROR("failed to access file with F_OK");
      }
      if (access(file_path, R_OK | W_OK) < 0) {
          THROW_ERROR("failed to access file");
      }
      if (access(file_path, R_OK | W_OK | X_OK) >= 0 || errno != EACCES) {
          THROW_ERROR("failed to access file with X_OK");
      }
      if (access(file_path, 0xF) >= 0 || errno != EINVAL) {
          THROW_ERROR("failed to access file with invalid mode");
      }
      if (remove_file(file_path) < 0) {
          return -1;
      }
      if (access(file_path, F_OK) >= 0 || errno != ENOENT) {
          THROW_ERROR("failed to access file after unlink");
      }
      return 0;
  }
  
  static int __test_faccessat_with_abs_path(const char *file_path) {
      if (faccessat(AT_FDCWD, file_path, F_OK, 0) < 0) {
          THROW_ERROR("failed to faccessat file with abs path");
      }
      if (faccessat(-1, file_path, F_OK, 0) < 0) {
          THROW_ERROR("failed to faccessat file with abs path and invalid dirfd");
      }
      if (remove_file(file_path) < 0) {
          return -1;
      }
      if (faccessat(AT_FDCWD, file_path, F_OK, 0) >= 0 || errno != ENOENT) {
          THROW_ERROR("failed to faccessat file after unlink");
      }
      return 0;
  }
  
  static int __test_faccessat_with_dirfd(const char *file_path) {
      char dir_buf[128] = { 0 };
      char base_buf[128] = { 0 };
      char *dir_name, *file_name;
      int dirfd, ret;
  
      ret = snprintf(dir_buf, sizeof(dir_buf), "%s", file_path);
      if (ret >= sizeof(dir_buf) || ret < 0) {
          THROW_ERROR("failed to copy file path to the dir buffer");
      }
      ret = snprintf(base_buf, sizeof(base_buf), "%s", file_path);
      if (ret >= sizeof(base_buf) || ret < 0) {
          THROW_ERROR("failed to copy file path to the base buffer");
      }
      dir_name = dirname(dir_buf);
      file_name = basename(base_buf);
      dirfd = open(dir_name, O_RDONLY);
      if (dirfd < 0) {
          THROW_ERROR("failed to open dir");
      }
      if (faccessat(dirfd, file_name, F_OK, 0) < 0) {
          close(dirfd);
          THROW_ERROR("failed to faccessat file with dirfd");
      }
      if (remove_file(file_path) < 0) {
          close(dirfd);
          return -1;
      }
      if (faccessat(dirfd, file_name, F_OK, 0) >= 0 || errno != ENOENT) {
          close(dirfd);
          THROW_ERROR("failed to faccessat file after unlink");
      }
      close(dirfd);
      return 0;
  }
  
  typedef int(*test_access_func_t)(const char *);
  
  static int test_access_framework(test_access_func_t fn) {
      const char *file_path = "/root/test_filesystem_access.txt";
      mode_t mode = 00666;
  
      if (create_file(file_path, mode) < 0) {
          return -1;
      }
      if (fn(file_path) < 0) {
          return -1;
      }
      return 0;
  }
  
  static int test_access() {
      return test_access_framework(__test_access);
  }
  
  static int test_faccessat_with_abs_path() {
      return test_access_framework(__test_faccessat_with_abs_path);
  }
  
  static int test_faccessat_with_dirfd() {
      return test_access_framework(__test_faccessat_with_dirfd);
  }
  
  // ============================================================================
  // Test suite main
  // ============================================================================
  
  static test_case_t test_cases[] = {
      TEST_CASE(test_access),
      TEST_CASE(test_faccessat_with_abs_path),
      TEST_CASE(test_faccessat_with_dirfd),
  };
  
  int main(int argc, const char *argv[]) {
      return test_suite_run(test_cases, ARRAY_SIZE(test_cases));
  }
  