1 files changed, 164 insertions, 0 deletions
diff --git a/src/net/cgo_unix.go b/src/net/cgo_unix.go
new file mode 100644
index 000000000..1f366ee5c
--- /dev/null
+++ b/src/net/cgo_unix.go
@@ -0,0 +1,164 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !netgo
+// +build darwin dragonfly freebsd linux netbsd openbsd
+
+package net
+
+/*
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+*/
+import "C"
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+func cgoLookupHost(name string) (addrs []string, err error, completed bool) {
+	ip, err, completed := cgoLookupIP(name)
+	for _, p := range ip {
+		addrs = append(addrs, p.String())
+	}
+	return
+}
+
+func cgoLookupPort(net, service string) (port int, err error, completed bool) {
+	acquireThread()
+	defer releaseThread()
+
+	var res *C.struct_addrinfo
+	var hints C.struct_addrinfo
+
+	switch net {
+	case "":
+		// no hints
+	case "tcp", "tcp4", "tcp6":
+		hints.ai_socktype = C.SOCK_STREAM
+		hints.ai_protocol = C.IPPROTO_TCP
+	case "udp", "udp4", "udp6":
+		hints.ai_socktype = C.SOCK_DGRAM
+		hints.ai_protocol = C.IPPROTO_UDP
+	default:
+		return 0, UnknownNetworkError(net), true
+	}
+	if len(net) >= 4 {
+		switch net[3] {
+		case '4':
+			hints.ai_family = C.AF_INET
+		case '6':
+			hints.ai_family = C.AF_INET6
+		}
+	}
+
+	s := C.CString(service)
+	defer C.free(unsafe.Pointer(s))
+	if C.getaddrinfo(nil, s, &hints, &res) == 0 {
+		defer C.freeaddrinfo(res)
+		for r := res; r != nil; r = r.ai_next {
+			switch r.ai_family {
+			default:
+				continue
+			case C.AF_INET:
+				sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.ai_addr))
+				p := (*[2]byte)(unsafe.Pointer(&sa.Port))
+				return int(p[0])<<8 | int(p[1]), nil, true
+			case C.AF_INET6:
+				sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.ai_addr))
+				p := (*[2]byte)(unsafe.Pointer(&sa.Port))
+				return int(p[0])<<8 | int(p[1]), nil, true
+			}
+		}
+	}
+	return 0, &AddrError{"unknown port", net + "/" + service}, true
+}
+
+func cgoLookupIPCNAME(name string) (addrs []IP, cname string, err error, completed bool) {
+	acquireThread()
+	defer releaseThread()
+
+	var res *C.struct_addrinfo
+	var hints C.struct_addrinfo
+
+	hints.ai_flags = cgoAddrInfoFlags()
+	hints.ai_socktype = C.SOCK_STREAM
+
+	h := C.CString(name)
+	defer C.free(unsafe.Pointer(h))
+	gerrno, err := C.getaddrinfo(h, nil, &hints, &res)
+	if gerrno != 0 {
+		var str string
+		if gerrno == C.EAI_NONAME {
+			str = noSuchHost
+		} else if gerrno == C.EAI_SYSTEM {
+			if err == nil {
+				// err should not be nil, but sometimes getaddrinfo returns
+				// gerrno == C.EAI_SYSTEM with err == nil on Linux.
+				// The report claims that it happens when we have too many
+				// open files, so use syscall.EMFILE (too many open files in system).
+				// Most system calls would return ENFILE (too many open files),
+				// so at the least EMFILE should be easy to recognize if this
+				// comes up again. golang.org/issue/6232.
+				err = syscall.EMFILE
+			}
+			str = err.Error()
+		} else {
+			str = C.GoString(C.gai_strerror(gerrno))
+		}
+		return nil, "", &DNSError{Err: str, Name: name}, true
+	}
+	defer C.freeaddrinfo(res)
+	if res != nil {
+		cname = C.GoString(res.ai_canonname)
+		if cname == "" {
+			cname = name
+		}
+		if len(cname) > 0 && cname[len(cname)-1] != '.' {
+			cname += "."
+		}
+	}
+	for r := res; r != nil; r = r.ai_next {
+		// We only asked for SOCK_STREAM, but check anyhow.
+		if r.ai_socktype != C.SOCK_STREAM {
+			continue
+		}
+		switch r.ai_family {
+		default:
+			continue
+		case C.AF_INET:
+			sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.ai_addr))
+			addrs = append(addrs, copyIP(sa.Addr[:]))
+		case C.AF_INET6:
+			sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.ai_addr))
+			addrs = append(addrs, copyIP(sa.Addr[:]))
+		}
+	}
+	return addrs, cname, nil, true
+}
+
+func cgoLookupIP(name string) (addrs []IP, err error, completed bool) {
+	addrs, _, err, completed = cgoLookupIPCNAME(name)
+	return
+}
+
+func cgoLookupCNAME(name string) (cname string, err error, completed bool) {
+	_, cname, err, completed = cgoLookupIPCNAME(name)
+	return
+}
+
+func copyIP(x IP) IP {
+	if len(x) < 16 {
+		return x.To16()
+	}
+	y := make(IP, len(x))
+	copy(y, x)
+	return y
+}