Unix domain socket support, Linux and Darwin.

R=r
DELTA=534  (353 added, 99 deleted, 82 changed)
OCL=28783
CL=28783

src/lib/net/net_darwin.go

@@ -43,7 +43,6 @@ func v6ToSockaddr(p IP, port int) (sa1 *syscall.Sockaddr, err os.Error) {
 	return (*syscall.Sockaddr)(unsafe.Pointer(sa)), nil
 }
 
-
 func sockaddrToIP(sa1 *syscall.Sockaddr) (p IP, port int, err os.Error) {
 	switch sa1.Family {
 	case syscall.AF_INET:
@@ -70,3 +69,32 @@ func listenBacklog() int64 {
 	return syscall.SOMAXCONN
 }
 
+func unixToSockaddr(name string) (sa1 *syscall.Sockaddr, err os.Error) {
+	sa := new(syscall.SockaddrUnix);
+	n := len(name);
+	if n >= len(sa.Path) || n == 0 {
+		return nil, os.EINVAL;
+	}
+	sa.Len = byte(3 + n);	// 2 for Family, Len; 1 for NUL
+	sa.Family = syscall.AF_UNIX;
+	for i := 0; i < len(name); i++ {
+		sa.Path[i] = name[i];
+	}
+	return (*syscall.Sockaddr)(unsafe.Pointer(sa)), nil;
+}
+
+func sockaddrToUnix(sa1 *syscall.Sockaddr) (string, os.Error) {
+	if sa1.Family != syscall.AF_UNIX || sa1.Len < 3 || sa1.Len > syscall.SizeofSockaddrUnix {
+		return "", os.EINVAL;
+	}
+	sa := (*syscall.SockaddrUnix)(unsafe.Pointer(sa1));
+	n := int(sa.Len) - 3;	// subtract leading Family, Len, terminating NUL
+	for i := 0; i < n; i++ {
+		if sa.Path[i] == 0 {
+			// found early NUL; assume Len is overestimating
+			n = i;
+			break;
+		}
+	}
+	return string(sa.Path[0:n]), nil;
+}

src/lib/net/net_linux.go

@@ -77,3 +77,47 @@ func listenBacklog() int64 {
 	return syscall.SOMAXCONN
 }
 
+func unixToSockaddr(name string) (sa1 *syscall.Sockaddr, err os.Error) {
+	sa := new(syscall.SockaddrUnix);
+	n := len(name);
+	if n >= len(sa.Path) || n == 0 {
+		return nil, os.EINVAL;
+	}
+	sa.Family = syscall.AF_UNIX;
+	for i := 0; i < len(name); i++ {
+		sa.Path[i] = name[i];
+	}
+
+	// Special case: @ in first position indicates
+	// an abstract socket, which has no file system
+	// representation and starts with a NUL byte
+	// when talking to the kernel about it.
+	if sa.Path[0] == '@' {
+		sa.Path[0] = 0;
+	}
+
+	return (*syscall.Sockaddr)(unsafe.Pointer(sa)), nil;
+}
+
+func sockaddrToUnix(sa1 *syscall.Sockaddr) (string, os.Error) {
+	if sa1.Family != syscall.AF_UNIX {
+		return "", os.EINVAL;
+	}
+
+	sa := (*syscall.SockaddrUnix)(unsafe.Pointer(sa1));
+
+	// @ special case (see comment in unixToSockaddr).
+	if sa.Path[0] == 0 {
+		// Not friendly to overwrite in place but
+		// okay in an internal function.
+		// The caller doesn't care if we do.
+		sa.Path[0] = '@';
+	}
+
+	// count length of path
+	n := 0;
+	for n < len(sa.Path) && sa.Path[n] != 0 {
+		n++;
+	}
+	return string(sa.Path[0:n]), nil;
+}

src/lib/net/tcpserver_test.go → src/lib/net/server_test.go

@@ -8,6 +8,7 @@ import (
 	"io";
 	"net";
 	"os";
+	"syscall";
 	"testing";
 )
 
@@ -83,3 +84,10 @@ func TestTcpServer(t *testing.T) {
 	doTest(t, "tcp", "0.0.0.0:9997", "[::ffff:127.0.0.1]:9997");
 }
 
+func TestUnixServer(t *testing.T) {
+	doTest(t, "unix", "/tmp/gotest.net", "/tmp/gotest.net");
+	if syscall.OS == "linux" {
+		// Test abstract unix domain socket, a Linux-ism
+		doTest(t, "unix", "@gotest/net", "@gotest/net");
+	}
+}

src/lib/os/error.go

@@ -77,5 +77,7 @@ var (
 	EAGAIN Error = Errno(syscall.EAGAIN);
 	EDOM Error = Errno(syscall.EDOM);
 	ERANGE Error = Errno(syscall.ERANGE);
+	EADDRINUSE Error = Errno(syscall.EADDRINUSE);
+	ECONNREFUSED Error = Errno(syscall.ECONNREFUSED);
 )
 

src/lib/syscall/socket_darwin.go

@@ -16,11 +16,6 @@ import (
 // creation of IPv6 sockets to return EAFNOSUPPORT.
 var SocketDisableIPv6 bool
 
-func SockaddrToSockaddrInet4(s *Sockaddr) *SockaddrInet4;
-func SockaddrToSockaddrInet6(s *Sockaddr) *SockaddrInet6;
-func SockaddrInet4ToSockaddr(s *SockaddrInet4) *Sockaddr;
-func SockaddrInet6ToSockaddr(s *SockaddrInet6) *Sockaddr;
-
 func Socket(domain, proto, typ int64) (ret int64, err int64) {
 	if domain == AF_INET6 && SocketDisableIPv6 {
 		return -1, EAFNOSUPPORT

src/lib/syscall/socket_linux.go

@@ -16,11 +16,6 @@ import (
 // creation of IPv6 sockets to return EAFNOSUPPORT.
 var SocketDisableIPv6 bool
 
-func SockaddrToSockaddrInet4(s *Sockaddr) *SockaddrInet4;
-func SockaddrToSockaddrInet6(s *Sockaddr) *SockaddrInet6;
-func SockaddrInet4ToSockaddr(s *SockaddrInet4) *Sockaddr;
-func SockaddrInet6ToSockaddr(s *SockaddrInet6) *Sockaddr;
-
 func saLen(s *Sockaddr) int64 {
 	switch s.Family {
 	case AF_UNIX: