/**
 * POSIX errno names ↔ numeric hints for guest errors and `/proc` introspection.
 * Values follow Linux/x86-64 style where Bare OS surfaces them in messages.
 */

export const BARE_OS_POSIX_ERRNO_MAP = Object.freeze({
  EPERM: 1,
  ENOENT: 2,
  ESRCH: 3,
  EINTR: 4,
  EIO: 5,
  ENXIO: 6,
  E2BIG: 7,
  ENOEXEC: 8,
  EBADF: 9,
  ECHILD: 10,
  EAGAIN: 11,
  ENOMEM: 12,
  EACCES: 13,
  EFAULT: 14,
  ENOTBLK: 15,
  EBUSY: 16,
  EEXIST: 17,
  EXDEV: 18,
  ENODEV: 19,
  ENOTDIR: 20,
  EISDIR: 21,
  EINVAL: 22,
  ENFILE: 23,
  EMFILE: 24,
  ENOTTY: 25,
  ETXTBSY: 26,
  EFBIG: 27,
  ENOSPC: 28,
  ESPIPE: 29,
  EROFS: 30,
  EMLINK: 31,
  EPIPE: 32,
  EDOM: 33,
  ERANGE: 34,
  ELOOP: 40,
  ENAMETOOLONG: 36,
  ENOSYS: 38,
  ENOTEMPTY: 39,
  EOPNOTSUPP: 95
})

/**
 * @param {string} name
 * @returns {number | undefined}
 */
export function bareOsErrnoNumber(name) {
  const k = String(name || '').toUpperCase()
  return /** @type {Record<string, number>} */ (BARE_OS_POSIX_ERRNO_MAP)[k]
}

/**
 * @returns {Record<string, number>}
 */
export function bareOsErrnoTableForProc() {
  return { ...BARE_OS_POSIX_ERRNO_MAP }
}