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Diffstat (limited to 'src/pkg/net/dnsclient.go')
-rw-r--r--src/pkg/net/dnsclient.go144
1 files changed, 72 insertions, 72 deletions
diff --git a/src/pkg/net/dnsclient.go b/src/pkg/net/dnsclient.go
index 064e1017b..439cae806 100644
--- a/src/pkg/net/dnsclient.go
+++ b/src/pkg/net/dnsclient.go
@@ -15,24 +15,24 @@
package net
import (
- "once";
- "os";
+ "once"
+ "os"
)
// DNSError represents a DNS lookup error.
type DNSError struct {
- Error string; // description of the error
- Name string; // name looked for
- Server string; // server used
+ Error string // description of the error
+ Name string // name looked for
+ Server string // server used
}
func (e *DNSError) String() string {
- s := "lookup " + e.Name;
+ s := "lookup " + e.Name
if e.Server != "" {
s += " on " + e.Server
}
- s += ": " + e.Error;
- return s;
+ s += ": " + e.Error
+ return s
}
const noSuchHost = "no such host"
@@ -43,53 +43,53 @@ func _Exchange(cfg *_DNS_Config, c Conn, name string) (m *_DNS_Msg, err os.Error
if len(name) >= 256 {
return nil, &DNSError{"name too long", name, ""}
}
- out := new(_DNS_Msg);
- out.id = 0x1234;
+ out := new(_DNS_Msg)
+ out.id = 0x1234
out.question = []_DNS_Question{
_DNS_Question{name, _DNS_TypeA, _DNS_ClassINET},
- };
- out.recursion_desired = true;
- msg, ok := out.Pack();
+ }
+ out.recursion_desired = true
+ msg, ok := out.Pack()
if !ok {
return nil, &DNSError{"internal error - cannot pack message", name, ""}
}
for attempt := 0; attempt < cfg.attempts; attempt++ {
- n, err := c.Write(msg);
+ n, err := c.Write(msg)
if err != nil {
return nil, err
}
- c.SetReadTimeout(1e9); // nanoseconds
+ c.SetReadTimeout(1e9) // nanoseconds
- buf := make([]byte, 2000); // More than enough.
- n, err = c.Read(buf);
+ buf := make([]byte, 2000) // More than enough.
+ n, err = c.Read(buf)
if isEAGAIN(err) {
- err = nil;
- continue;
+ err = nil
+ continue
}
if err != nil {
return nil, err
}
- buf = buf[0:n];
- in := new(_DNS_Msg);
+ buf = buf[0:n]
+ in := new(_DNS_Msg)
if !in.Unpack(buf) || in.id != out.id {
continue
}
- return in, nil;
+ return in, nil
}
- var server string;
+ var server string
if a := c.RemoteAddr(); a != nil {
server = a.String()
}
- return nil, &DNSError{"no answer from server", name, server};
+ return nil, &DNSError{"no answer from server", name, server}
}
// Find answer for name in dns message.
// On return, if err == nil, addrs != nil.
func answer(name, server string, dns *_DNS_Msg) (addrs []string, err *DNSError) {
- addrs = make([]string, 0, len(dns.answer));
+ addrs = make([]string, 0, len(dns.answer))
if dns.rcode == _DNS_RcodeNameError && dns.recursion_available {
return nil, &DNSError{noSuchHost, name, ""}
@@ -109,31 +109,31 @@ func answer(name, server string, dns *_DNS_Msg) (addrs []string, err *DNSError)
// all the answers we need in this one packet.
Cname:
for cnameloop := 0; cnameloop < 10; cnameloop++ {
- addrs = addrs[0:0];
+ addrs = addrs[0:0]
for i := 0; i < len(dns.answer); i++ {
- rr := dns.answer[i];
- h := rr.Header();
+ rr := dns.answer[i]
+ h := rr.Header()
if h.Class == _DNS_ClassINET && h.Name == name {
switch h.Rrtype {
case _DNS_TypeA:
- n := len(addrs);
- a := rr.(*_DNS_RR_A).A;
- addrs = addrs[0 : n+1];
- addrs[n] = IPv4(byte(a>>24), byte(a>>16), byte(a>>8), byte(a)).String();
+ n := len(addrs)
+ a := rr.(*_DNS_RR_A).A
+ addrs = addrs[0 : n+1]
+ addrs[n] = IPv4(byte(a>>24), byte(a>>16), byte(a>>8), byte(a)).String()
case _DNS_TypeCNAME:
// redirect to cname
- name = rr.(*_DNS_RR_CNAME).Cname;
- continue Cname;
+ name = rr.(*_DNS_RR_CNAME).Cname
+ continue Cname
}
}
}
if len(addrs) == 0 {
return nil, &DNSError{noSuchHost, name, server}
}
- return addrs, nil;
+ return addrs, nil
}
- return nil, &DNSError{"too many redirects", name, server};
+ return nil, &DNSError{"too many redirects", name, server}
}
// Do a lookup for a single name, which must be rooted
@@ -149,36 +149,36 @@ func tryOneName(cfg *_DNS_Config, name string) (addrs []string, err os.Error) {
// The DNS config parser has already checked that
// all the cfg.servers[i] are IP addresses, which
// Dial will use without a DNS lookup.
- server := cfg.servers[i] + ":53";
- c, cerr := Dial("udp", "", server);
+ server := cfg.servers[i] + ":53"
+ c, cerr := Dial("udp", "", server)
if cerr != nil {
- err = cerr;
- continue;
+ err = cerr
+ continue
}
- msg, merr := _Exchange(cfg, c, name);
- c.Close();
+ msg, merr := _Exchange(cfg, c, name)
+ c.Close()
if merr != nil {
- err = merr;
- continue;
+ err = merr
+ continue
}
- var dnserr *DNSError;
- addrs, dnserr = answer(name, server, msg);
+ var dnserr *DNSError
+ addrs, dnserr = answer(name, server, msg)
if dnserr != nil {
err = dnserr
} else {
- err = nil // nil os.Error, not nil *DNSError
+ err = nil // nil os.Error, not nil *DNSError
}
if dnserr == nil || dnserr.Error == noSuchHost {
break
}
}
- return;
+ return
}
var cfg *_DNS_Config
var dnserr os.Error
-func loadConfig() { cfg, dnserr = _DNS_ReadConfig() }
+func loadConfig() { cfg, dnserr = _DNS_ReadConfig() }
func isDomainName(s string) bool {
// Requirements on DNS name:
@@ -192,14 +192,14 @@ func isDomainName(s string) bool {
if len(s) == 0 {
return false
}
- if s[len(s)-1] != '.' { // simplify checking loop: make name end in dot
+ if s[len(s)-1] != '.' { // simplify checking loop: make name end in dot
s += "."
}
- last := byte('.');
- ok := false; // ok once we've seen a letter
+ last := byte('.')
+ ok := false // ok once we've seen a letter
for i := 0; i < len(s); i++ {
- c := s[i];
+ c := s[i]
switch {
default:
return false
@@ -218,10 +218,10 @@ func isDomainName(s string) bool {
return false
}
}
- last = c;
+ last = c
}
- return ok;
+ return ok
}
// LookupHost looks up the host name using the local DNS resolver.
@@ -231,25 +231,25 @@ func LookupHost(name string) (cname string, addrs []string, err os.Error) {
if !isDomainName(name) {
return name, nil, &DNSError{"invalid domain name", name, ""}
}
- once.Do(loadConfig);
+ once.Do(loadConfig)
if dnserr != nil || cfg == nil {
- err = dnserr;
- return;
+ err = dnserr
+ return
}
// If name is rooted (trailing dot) or has enough dots,
// try it by itself first.
- rooted := len(name) > 0 && name[len(name)-1] == '.';
+ rooted := len(name) > 0 && name[len(name)-1] == '.'
if rooted || count(name, '.') >= cfg.ndots {
- rname := name;
+ rname := name
if !rooted {
rname += "."
}
// Can try as ordinary name.
- addrs, err = tryOneName(cfg, rname);
+ addrs, err = tryOneName(cfg, rname)
if err == nil {
- cname = rname;
- return;
+ cname = rname
+ return
}
}
if rooted {
@@ -258,26 +258,26 @@ func LookupHost(name string) (cname string, addrs []string, err os.Error) {
// Otherwise, try suffixes.
for i := 0; i < len(cfg.search); i++ {
- rname := name + "." + cfg.search[i];
+ rname := name + "." + cfg.search[i]
if rname[len(rname)-1] != '.' {
rname += "."
}
- addrs, err = tryOneName(cfg, rname);
+ addrs, err = tryOneName(cfg, rname)
if err == nil {
- cname = rname;
- return;
+ cname = rname
+ return
}
}
// Last ditch effort: try unsuffixed.
- rname := name;
+ rname := name
if !rooted {
rname += "."
}
- addrs, err = tryOneName(cfg, rname);
+ addrs, err = tryOneName(cfg, rname)
if err == nil {
- cname = rname;
- return;
+ cname = rname
+ return
}
- return;
+ return
}
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-28 04:51:04 +0000