package os

import "internal/testlog"

// Stat returns a [FileInfo] describing the named file.
// If there is an error, it will be of type [*PathError].
func Stat(name string) (FileInfo, error) {
	testlog.Stat(name)
	return statNolog(name)
}

// Lstat returns a [FileInfo] describing the named file.
// If the file is a symbolic link, the returned FileInfo

}

// SafeToRetry returns an error if the durationBeforeRetry period for the given
// lastErrorTime has not yet expired. Otherwise it returns nil.
func (expBackoff *ExponentialBackoff) SafeToRetry(operationName string) error {
	if time.Since(expBackoff.lastErrorTime) <= expBackoff.durationBeforeRetry {
		return NewExponentialBackoffError(operationName, *expBackoff)
	}

	return nil
}

  static int getHashPrefix(int value, int mask) {
    return value & ~mask;
  }

  /** Returns the index, or 0 if the entry is "null". */
  static int getNext(int entry, int mask) {
    return entry & mask;
  }

  /** Returns a new value combining the prefix and suffix using the given mask. */
  static int maskCombine(int prefix, int suffix, int mask) {

    ): Set<Name>

    /**
     * Returns the list of subpackages for a given package, which satisfies [nameFilter].
     *
     * The returned sub-package list contains all packages with some Kotlin declarations inside.
     */
    public abstract fun getKotlinOnlySubPackagesFqNames(packageFqName: FqName, nameFilter: (Name) -> Boolean): Set<Name>

    /**

// Stops and returns as soon as:
// 1. the condition check returns true or an error,
// 2. `backoff.Steps` checks of the condition have been done, or
// 3. a sleep truncated by the cap on duration has been completed.
// In case (1) the returned error is what the condition function returned.
// In all other cases, ErrWaitTimeout is returned.
//

   * opening the data stream.
   *
   * <p>The default implementation returns {@link Optional#absent}. Some sources, such as a file,
   * may return a non-absent value. Note that in such cases, it is <i>possible</i> that this method
   * will return a different number of bytes than would be returned by reading all of the bytes (for
   * example, some special files may return a size of 0 despite actually having content when read).
   *

  /** Returns the empty array. */
  public static ImmutableDoubleArray of() {
    return EMPTY;
  }

  /** Returns an immutable array containing a single value. */
  public static ImmutableDoubleArray of(double e0) {
    return new ImmutableDoubleArray(new double[] {e0});
  }

  /** Returns an immutable array containing the given values, in order. */

  /** Returns the empty array. */
  public static ImmutableLongArray of() {
    return EMPTY;
  }

  /** Returns an immutable array containing a single value. */
  public static ImmutableLongArray of(long e0) {
    return new ImmutableLongArray(new long[] {e0});
  }

  /** Returns an immutable array containing the given values, in order. */

// value (which may be empty) is returned and the boolean is true.
// Otherwise the returned value will be the default and the boolean will
// be false.
func (v StringVar) Lookup() (string, bool) {
	result, ok := os.LookupEnv(v.Name)
	if !ok {
		result = v.DefaultValue
	}

	return result, ok
}

// Get retrieves the value of the environment variable.

const MaxUintptr = ^uintptr(0)

// MulUintptr returns a * b and whether the multiplication overflowed.
// On supported platforms this is an intrinsic lowered by the compiler.
func MulUintptr(a, b uintptr) (uintptr, bool) {
	if a|b < 1<<(4*goarch.PtrSize) || a == 0 {
		return a * b, false
	}
	overflow := b > MaxUintptr/a
	return a * b, overflow
}

// Mul64 returns the 128-bit product of x and y: (hi, lo) = x * y