util

Documentation

Overview

Package util contains internal routines used by the styx packages.

Index

• func IsTempErr(err error) bool
• type BlackHole
  • func (BlackHole) Close() error
  • func (BlackHole) Read(p []byte) (int, error)
  • func (BlackHole) Write(p []byte) (int, error)
• type RefCount
  • func (r *RefCount) DecRef() (remaining bool)
  • func (r *RefCount) IncRef()
• type SectionWriter
  • func NewSectionWriter(w io.WriterAt, off, n int64) *SectionWriter
  • func (s *SectionWriter) Write(p []byte) (int, error)

Examples

• RefCount

Functions

func IsTempErr

func IsTempErr(err error) bool

IsTempErr returns true if an error exports a Temporary() method that returns true.

Types

type BlackHole

type BlackHole struct{}

A BlackHole is an io.ReadWriteCloser that accepts an infinite amount of input and produces no output.

func (BlackHole) Close

func (BlackHole) Close() error

func (BlackHole) Read

func (BlackHole) Read(p []byte) (int, error)

func (BlackHole) Write

func (BlackHole) Write(p []byte) (int, error)

type RefCount

type RefCount struct {
	// contains filtered or unexported fields
}

A Refcount can be embedded in structures to provide reference-counting of resources.

Example

package main

import "aqwari.net/net/styx/internal/util"

type Session struct {
	util.RefCount
	User, Tree string
	Requests   chan []byte
}

func (s *Session) end() {
	select {
	case <-s.Requests:
		return
	}
}

func main() {
	s := &Session{Requests: make(chan []byte)}
	for i := 0; i < 10; i++ {
		s.IncRef()
	}

	for i := 0; i < 20; i++ {
		if !s.DecRef() {
			s.end()
			break
		}
	}
}

func (*RefCount) DecRef

func (r *RefCount) DecRef() (remaining bool)

DecRef decrements refcount by 1. If the reference count has reached 0, DecRef will return false.

func (*RefCount) IncRef

func (r *RefCount) IncRef()

IncRef increments refcount by 1. It is a run-time panic to create more than ^uint64(0) references.

type SectionWriter

type SectionWriter struct {
	// contains filtered or unexported fields
}

Section writer provides a partial analogue io.SectionReader, for writers.

func NewSectionWriter

func NewSectionWriter(w io.WriterAt, off, n int64) *SectionWriter

func (*SectionWriter) Write

func (s *SectionWriter) Write(p []byte) (int, error)