From 7ba0773fd792c43321254b04c77ff2bcbe5d9974 Mon Sep 17 00:00:00 2001
From: nadoo <287492+nadoo@users.noreply.github.com>
Date: Sun, 10 Sep 2017 20:33:35 +0800
Subject: [PATCH] general: add some comments to functions

---
 dns.go             | 2 +-
 dnstun.go          | 4 ++--
 forwarder.go       | 7 +++++--
 http.go            | 2 +-
 ipset_linux.go     | 4 +++-
 ipset_other.go     | 6 ++++--
 log.go             | 2 +-
 mixed.go           | 2 +-
 redir_linux_386.go | 3 ++-
 redir_other.go     | 2 +-
 rule.go            | 7 +++++--
 server.go          | 2 +-
 socks5.go          | 2 +-
 strategy.go        | 6 +++---
 tcptun.go          | 2 +-
 tproxy.go          | 5 ++++-
 tproxy_other.go    | 1 +
 17 files changed, 37 insertions(+), 22 deletions(-)

diff --git a/dns.go b/dns.go
index 397db47..25149e1 100644
--- a/dns.go
+++ b/dns.go
@@ -62,7 +62,7 @@ type DNS struct {
 	answerHandlers []DNSAnswerHandler
 }
 
-// NewDNS returns a dns forwarder. client -> dns.udp -> glider -> forwarder -> remote dns addr
+// NewDNS returns a dns forwarder. client[dns.udp] -> glider[tcp] -> forwarder[dns.tcp] -> remote dns addr
 func NewDNS(addr, raddr string, sDialer Dialer) (*DNS, error) {
 	s := &DNS{
 		Forwarder: NewForwarder(addr, nil),
diff --git a/dnstun.go b/dnstun.go
index df4b53f..2c0c04c 100644
--- a/dnstun.go
+++ b/dnstun.go
@@ -2,7 +2,7 @@
 
 package main
 
-// DNSTun .
+// DNSTun struct
 type DNSTun struct {
 	*Forwarder        // as client
 	sDialer    Dialer // dialer for server
@@ -13,7 +13,7 @@ type DNSTun struct {
 	tcp *TCPTun
 }
 
-// NewDNSTun returns a dns forwarder.
+// NewDNSTun returns a dns tunnel forwarder.
 func NewDNSTun(addr, raddr string, sDialer Dialer) (*DNSTun, error) {
 	s := &DNSTun{
 		Forwarder: NewForwarder(addr, nil),
diff --git a/forwarder.go b/forwarder.go
index cc72f16..ea34525 100644
--- a/forwarder.go
+++ b/forwarder.go
@@ -2,13 +2,13 @@ package main
 
 import "net"
 
-// Forwarder .
+// Forwarder struct
 type Forwarder struct {
 	addr    string
 	cDialer Dialer
 }
 
-// NewForwarder .
+// NewForwarder returns a base forwarder
 func NewForwarder(addr string, cDialer Dialer) *Forwarder {
 	if cDialer == nil {
 		cDialer = Direct
@@ -17,12 +17,15 @@ func NewForwarder(addr string, cDialer Dialer) *Forwarder {
 	return &Forwarder{addr: addr, cDialer: cDialer}
 }
 
+// Addr returns forwarder's address
 func (p *Forwarder) Addr() string { return p.addr }
 
+// Dial to remote addr via cDialer
 func (p *Forwarder) Dial(network, addr string) (net.Conn, error) {
 	return p.cDialer.Dial(network, addr)
 }
 
+// NextDialer returns the next cDialer
 func (p *Forwarder) NextDialer(dstAddr string) Dialer {
 	return p.cDialer
 }
diff --git a/http.go b/http.go
index e4d9ec4..f8d4f8c 100644
--- a/http.go
+++ b/http.go
@@ -16,7 +16,7 @@ import (
 	"time"
 )
 
-// HTTP .
+// HTTP struct
 type HTTP struct {
 	*Forwarder        // as client
 	sDialer    Dialer // dialer for server
diff --git a/ipset_linux.go b/ipset_linux.go
index e0065c5..48b68d7 100644
--- a/ipset_linux.go
+++ b/ipset_linux.go
@@ -53,6 +53,7 @@ const NLA_F_NET_BYTEORDER = (1 << 14)
 var nextSeqNr uint32
 var nativeEndian binary.ByteOrder
 
+// IPSetManager struct
 type IPSetManager struct {
 	fd  int
 	lsa syscall.SockaddrNetlink
@@ -61,6 +62,7 @@ type IPSetManager struct {
 	domainSet sync.Map
 }
 
+// NewIPSetManager returns a IPSetManager
 func NewIPSetManager(mainSet string, rules []*RuleConf) (*IPSetManager, error) {
 	fd, err := syscall.Socket(syscall.AF_NETLINK, syscall.SOCK_RAW, syscall.NETLINK_NETFILTER)
 	if err != nil {
@@ -111,7 +113,7 @@ func NewIPSetManager(mainSet string, rules []*RuleConf) (*IPSetManager, error) {
 	return m, nil
 }
 
-// AddDomainIP used to update ipset according to domainSet rule
+// AddDomainIP implements the DNSAnswerHandler function, used to update ipset according to domainSet rule
 func (m *IPSetManager) AddDomainIP(domain, ip string) error {
 
 	if ip != "" {
diff --git a/ipset_other.go b/ipset_other.go
index 1f2857f..5d99bfe 100644
--- a/ipset_other.go
+++ b/ipset_other.go
@@ -4,13 +4,15 @@ package main
 
 import "errors"
 
-type IPSetManager struct {
-}
+// IPSetManager struct
+type IPSetManager struct{}
 
+// NewIPSetManager returns a IPSetManager
 func NewIPSetManager(mainSet string, rules []*RuleConf) (*IPSetManager, error) {
 	return nil, errors.New("ipset not supported on this os")
 }
 
+// AddDomainIP implements the DNSAnswerHandler function
 func (m *IPSetManager) AddDomainIP(domain, ip string) error {
 	return errors.New("ipset not supported on this os")
 }
diff --git a/log.go b/log.go
index b14bafe..dd88acc 100644
--- a/log.go
+++ b/log.go
@@ -2,7 +2,7 @@ package main
 
 import "log"
 
-// LogFunc .
+// LogFunc defines a simple log function
 type LogFunc func(f string, v ...interface{})
 
 var logf LogFunc
diff --git a/mixed.go b/mixed.go
index c666881..7e2f6ac 100644
--- a/mixed.go
+++ b/mixed.go
@@ -17,7 +17,7 @@ var httpMethods = [...][]byte{
 	[]byte("TRACE"),
 }
 
-// MixedProxy .
+// MixedProxy struct
 type MixedProxy struct {
 	sDialer Dialer
 
diff --git a/redir_linux_386.go b/redir_linux_386.go
index 8b8db6f..d19d48f 100644
--- a/redir_linux_386.go
+++ b/redir_linux_386.go
@@ -5,7 +5,8 @@ import (
 	"unsafe"
 )
 
-const GETSOCKOPT = 15 // https://golang.org/src/syscall/syscall_linux_386.go#L183
+// https://github.com/golang/go/blob/9e6b79a5dfb2f6fe4301ced956419a0da83bd025/src/syscall/syscall_linux_386.go#L196
+const GETSOCKOPT = 15
 
 func socketcall(call, a0, a1, a2, a3, a4, a5 uintptr) error {
 	var a [6]uintptr
diff --git a/redir_other.go b/redir_other.go
index 41cf4df..c26f857 100644
--- a/redir_other.go
+++ b/redir_other.go
@@ -7,7 +7,7 @@ import (
 	"log"
 )
 
-// RedirProxy .
+// RedirProxy struct
 type RedirProxy struct{}
 
 // NewRedirProxy returns a redirect proxy.
diff --git a/rule.go b/rule.go
index 21451f4..920d486 100644
--- a/rule.go
+++ b/rule.go
@@ -7,7 +7,7 @@ import (
 	"sync"
 )
 
-// RuleDialer .
+// RuleDialer struct
 type RuleDialer struct {
 	gDialer Dialer
 
@@ -16,7 +16,7 @@ type RuleDialer struct {
 	cidrMap   sync.Map
 }
 
-// NewRuleDialer .
+// NewRuleDialer returns a new rule dialer
 func NewRuleDialer(rules []*RuleConf, gDialer Dialer) *RuleDialer {
 	rd := &RuleDialer{gDialer: gDialer}
 
@@ -55,8 +55,10 @@ func NewRuleDialer(rules []*RuleConf, gDialer Dialer) *RuleDialer {
 	return rd
 }
 
+// Addr returns RuleDialer's address, always be "RULES"
 func (rd *RuleDialer) Addr() string { return "RULES" }
 
+// NextDialer return next dialer according to rule
 func (p *RuleDialer) NextDialer(dstAddr string) Dialer {
 
 	// TODO: change to index finders
@@ -106,6 +108,7 @@ func (p *RuleDialer) NextDialer(dstAddr string) Dialer {
 	return p.gDialer
 }
 
+// Dial dials to targer addr and return a conn
 func (rd *RuleDialer) Dial(network, addr string) (net.Conn, error) {
 	return rd.NextDialer(addr).Dial(network, addr)
 }
diff --git a/server.go b/server.go
index 1054c45..ebc6ab6 100644
--- a/server.go
+++ b/server.go
@@ -6,7 +6,7 @@ import (
 	"strings"
 )
 
-// Server .
+// Server interface
 type Server interface {
 	// ListenAndServe as proxy server, use only in server mode.
 	ListenAndServe()
diff --git a/socks5.go b/socks5.go
index 300b890..68ebd08 100644
--- a/socks5.go
+++ b/socks5.go
@@ -55,7 +55,7 @@ var socks5Errors = []string{
 	"address type not supported",
 }
 
-// SOCKS5 .
+// SOCKS5 struct
 type SOCKS5 struct {
 	*Forwarder
 	sDialer Dialer
diff --git a/strategy.go b/strategy.go
index 312f5d8..4f6dd8c 100644
--- a/strategy.go
+++ b/strategy.go
@@ -8,7 +8,7 @@ import (
 	"time"
 )
 
-// NewStrategyDialer .
+// NewStrategyDialer returns a new Strategy Dialer
 func NewStrategyDialer(strategy string, dialers []Dialer, website string, duration int) Dialer {
 	var dialer Dialer
 	if len(dialers) == 0 {
@@ -32,7 +32,7 @@ func NewStrategyDialer(strategy string, dialers []Dialer, website string, durati
 	return dialer
 }
 
-// rrDialer
+// rrDialer is the base struct of strategy dialer
 type rrDialer struct {
 	dialers []Dialer
 	idx     int
@@ -44,7 +44,7 @@ type rrDialer struct {
 	duration int
 }
 
-// newRRDialer .
+// newRRDialer returns a new rrDialer
 func newRRDialer(dialers []Dialer, website string, duration int) *rrDialer {
 	rr := &rrDialer{dialers: dialers}
 
diff --git a/tcptun.go b/tcptun.go
index 51626e1..bd1934b 100644
--- a/tcptun.go
+++ b/tcptun.go
@@ -2,7 +2,7 @@ package main
 
 import "net"
 
-// TCPTun .
+// TCPTun struct
 type TCPTun struct {
 	*Forwarder
 	sDialer Dialer
diff --git a/tproxy.go b/tproxy.go
index 5db9e67..0058e93 100644
--- a/tproxy.go
+++ b/tproxy.go
@@ -7,6 +7,7 @@ import (
 	"syscall"
 )
 
+// TProxy struct
 type TProxy struct {
 	*Forwarder        // as client
 	sDialer    Dialer // dialer for server
@@ -28,10 +29,12 @@ func (s *TProxy) ListenAndServe() {
 	s.ListenAndServeUDP()
 }
 
+// ListenAndServeTCP .
 func (s *TProxy) ListenAndServeTCP() {
-
+	logf("proxy-tproxy tcp mode not supported now, please use 'redir' instead")
 }
 
+// ListenAndServeUDP .
 func (s *TProxy) ListenAndServeUDP() {
 	laddr, err := net.ResolveUDPAddr("udp", s.addr)
 	if err != nil {
diff --git a/tproxy_other.go b/tproxy_other.go
index ff8b3c1..f5dbaeb 100644
--- a/tproxy_other.go
+++ b/tproxy_other.go
@@ -7,6 +7,7 @@ import (
 	"log"
 )
 
+// TProxy struct
 type TProxy struct{}
 
 // NewTProxy returns a tproxy.