syscall: add SetsockoptIpMreq

notes:
* due to Issue 1466 the Msghdr struct for
 src/pkg/syscall/ztypes_darwin_386.go
 src/pkg/syscall/ztypes_darwin_amd64.go
had to be edited after the godefs generation.
* ztypes_*.go files for linux, freebsd and darwin
have been prepared on the correct host OS and ARCH.
While the total increase is a dozen lines per file
the diff is larger due to a change to godefs,
 http://code.google.com/p/go/source/detail?r=c79e30afe9c8
while has altered the names of Pad members which
causes gofmt to realign the affected structs

R=rsc, mikioh
CC=golang-dev
https://golang.org/cl/4119053

src/pkg/syscall/syscall_bsd.go

@@ -343,6 +343,10 @@ func SetsockoptLinger(fd, level, opt int, l *Linger) (errno int) {
 	return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(l)), unsafe.Sizeof(*l))
 }
 
+func SetsockoptIpMreq(fd, level, opt int, mreq *IpMreq) (errno int) {
+	return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(mreq)), unsafe.Sizeof(*mreq))
+}
+
 func SetsockoptString(fd, level, opt int, s string) (errno int) {
 	return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(&[]byte(s)[0])), len(s))
 }

src/pkg/syscall/syscall_linux.go

@@ -428,6 +428,10 @@ func SetsockoptLinger(fd, level, opt int, l *Linger) (errno int) {
 	return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(l)), unsafe.Sizeof(*l))
 }
 
+func SetsockoptIpMreq(fd, level, opt int, mreq *IpMreq) (errno int) {
+	return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(mreq)), unsafe.Sizeof(*mreq))
+}
+
 func SetsockoptString(fd, level, opt int, s string) (errno int) {
 	return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(&[]byte(s)[0])), len(s))
 }

src/pkg/syscall/types_darwin.c

@@ -104,6 +104,7 @@ typedef struct sockaddr_any $RawSockaddrAny;
 typedef socklen_t $_Socklen;
 typedef struct linger $Linger;
 typedef struct iovec $Iovec;
+typedef struct ip_mreq $IpMreq;
 typedef struct msghdr $Msghdr;
 typedef struct cmsghdr $Cmsghdr;
 
@@ -113,6 +114,7 @@ enum {
 	$SizeofSockaddrAny = sizeof(struct sockaddr_any),
 	$SizeofSockaddrUnix = sizeof(struct sockaddr_un),
 	$SizeofLinger = sizeof(struct linger),
+	$SizeofIpMreq = sizeof(struct ip_mreq),
 	$SizeofMsghdr = sizeof(struct msghdr),
 	$SizeofCmsghdr = sizeof(struct cmsghdr),
 };

src/pkg/syscall/types_freebsd.c

@@ -116,6 +116,7 @@ typedef struct sockaddr_any $RawSockaddrAny;
 typedef socklen_t $_Socklen;
 typedef struct linger $Linger;
 typedef struct iovec $Iovec;
+typedef struct ip_mreq $IpMreq;
 typedef struct msghdr $Msghdr;
 typedef struct cmsghdr $Cmsghdr;
 
@@ -125,6 +126,7 @@ enum {
 	$SizeofSockaddrAny = sizeof(struct sockaddr_any),
 	$SizeofSockaddrUnix = sizeof(struct sockaddr_un),
 	$SizeofLinger = sizeof(struct linger),
+	$SizeofIpMreq = sizeof(struct ip_mreq),
 	$SizeofMsghdr = sizeof(struct msghdr),
 	$SizeofCmsghdr = sizeof(struct cmsghdr),
 };

src/pkg/syscall/types_linux.c

@@ -109,6 +109,7 @@ typedef struct sockaddr_any $RawSockaddrAny;
 typedef socklen_t $_Socklen;
 typedef struct linger $Linger;
 typedef struct iovec $Iovec;
+typedef struct ip_mreq $IpMreq;
 typedef struct msghdr $Msghdr;
 typedef struct cmsghdr $Cmsghdr;
 typedef struct ucred $Ucred;
@@ -120,6 +121,7 @@ enum {
 	$SizeofSockaddrUnix = sizeof(struct sockaddr_un),
 	$SizeofSockaddrLinklayer = sizeof(struct sockaddr_ll),
 	$SizeofLinger = sizeof(struct linger),
+	$SizeofIpMreq = sizeof(struct ip_mreq),	
 	$SizeofMsghdr = sizeof(struct msghdr),
 	$SizeofCmsghdr = sizeof(struct cmsghdr),
 	$SizeofUcred = sizeof(struct ucred),

src/pkg/syscall/ztypes_darwin_386.go

@@ -17,6 +17,7 @@ const (
 	SizeofSockaddrAny   = 0x6c
 	SizeofSockaddrUnix  = 0x6a
 	SizeofLinger        = 0x8
+	SizeofIpMreq        = 0x8
 	SizeofMsghdr        = 0x1c
 	SizeofCmsghdr       = 0xc
 	PTRACE_TRACEME      = 0
@@ -150,7 +151,7 @@ type Dirent struct {
 	Namlen       uint16
 	Type         uint8
 	Name         [1024]int8
-	Pad0    [3]byte
+	Pad_godefs_0 [3]byte
 }
 
 type RawSockaddrInet4 struct {
@@ -199,6 +200,11 @@ type Iovec struct {
 	Len  uint32
 }
 
+type IpMreq struct {
+	Multiaddr [4]byte /* in_addr */
+	Interface [4]byte /* in_addr */
+}
+
 type Msghdr struct {
 	Name       *byte
 	Namelen    uint32

src/pkg/syscall/ztypes_darwin_amd64.go

@@ -17,6 +17,7 @@ const (
 	SizeofSockaddrAny   = 0x6c
 	SizeofSockaddrUnix  = 0x6a
 	SizeofLinger        = 0x8
+	SizeofIpMreq        = 0x8
 	SizeofMsghdr        = 0x30
 	SizeofCmsghdr       = 0xc
 	PTRACE_TRACEME      = 0
@@ -42,7 +43,7 @@ type Timespec struct {
 type Timeval struct {
 	Sec          int64
 	Usec         int32
-	Pad0 [4]byte
+	Pad_godefs_0 [4]byte
 }
 
 type Rusage struct {
@@ -79,7 +80,7 @@ type Stat_t struct {
 	Uid           uint32
 	Gid           uint32
 	Rdev          int32
-	Pad0          [4]byte
+	Pad_godefs_0  [4]byte
 	Atimespec     Timespec
 	Mtimespec     Timespec
 	Ctimespec     Timespec
@@ -131,7 +132,7 @@ type Fstore_t struct {
 type Radvisory_t struct {
 	Offset       int64
 	Count        int32
-	Pad0   [4]byte
+	Pad_godefs_0 [4]byte
 }
 
 type Fbootstraptransfer_t struct {
@@ -153,7 +154,7 @@ type Dirent struct {
 	Namlen       uint16
 	Type         uint8
 	Name         [1024]int8
-	Pad0    [3]byte
+	Pad_godefs_0 [3]byte
 }
 
 type RawSockaddrInet4 struct {
@@ -202,13 +203,18 @@ type Iovec struct {
 	Len  uint64
 }
 
+type IpMreq struct {
+	Multiaddr [4]byte /* in_addr */
+	Interface [4]byte /* in_addr */
+}
+
 type Msghdr struct {
 	Name         *byte
 	Namelen      uint32
-	Pad0       [4]byte
+	Pad_godefs_0 [4]byte
 	Iov          *Iovec
 	Iovlen       int32
-	Pad1       [4]byte
+	Pad_godefs_1 [4]byte
 	Control      *byte
 	Controllen   uint32
 	Flags        int32

src/pkg/syscall/ztypes_freebsd_386.go

@@ -31,6 +31,7 @@ const (
 	SizeofSockaddrAny   = 0x6c
 	SizeofSockaddrUnix  = 0x6a
 	SizeofLinger        = 0x8
+	SizeofIpMreq        = 0x8
 	SizeofMsghdr        = 0x1c
 	SizeofCmsghdr       = 0xc
 	PTRACE_TRACEME      = 0
@@ -102,8 +103,8 @@ type Stat_t struct {
 	Gen           uint32
 	Lspare        int32
 	Birthtimespec Timespec
-	Pad0          uint32
-	Pad1          uint32
+	Pad_godefs_0  uint32
+	Pad_godefs_1  uint32
 }
 
 type Statfs_t struct {
@@ -194,6 +195,11 @@ type Iovec struct {
 	Len  uint32
 }
 
+type IpMreq struct {
+	Multiaddr [4]byte /* in_addr */
+	Interface [4]byte /* in_addr */
+}
+
 type Msghdr struct {
 	Name       *byte
 	Namelen    uint32

src/pkg/syscall/ztypes_freebsd_amd64.go

@@ -31,6 +31,7 @@ const (
 	SizeofSockaddrAny   = 0x6c
 	SizeofSockaddrUnix  = 0x6a
 	SizeofLinger        = 0x8
+	SizeofIpMreq        = 0x8
 	SizeofMsghdr        = 0x30
 	SizeofCmsghdr       = 0xc
 	PTRACE_TRACEME      = 0
@@ -102,8 +103,8 @@ type Stat_t struct {
 	Gen           uint32
 	Lspare        int32
 	Birthtimespec Timespec
-	Pad0          uint8
-	Pad1          uint8
+	Pad_godefs_0  uint8
+	Pad_godefs_1  uint8
 }
 
 type Statfs_t struct {
@@ -138,7 +139,7 @@ type Flock_t struct {
 	Type         int16
 	Whence       int16
 	Sysid        int32
-	Pad0   [4]byte
+	Pad_godefs_0 [4]byte
 }
 
 type Dirent struct {
@@ -195,13 +196,18 @@ type Iovec struct {
 	Len  uint64
 }
 
+type IpMreq struct {
+	Multiaddr [4]byte /* in_addr */
+	Interface [4]byte /* in_addr */
+}
+
 type Msghdr struct {
 	Name         *byte
 	Namelen      uint32
-	Pad0       [4]byte
+	Pad_godefs_0 [4]byte
 	Iov          *Iovec
 	Iovlen       int32
-	Pad1       [4]byte
+	Pad_godefs_1 [4]byte
 	Control      *byte
 	Controllen   uint32
 	Flags        int32

src/pkg/syscall/ztypes_linux_386.go

@@ -18,6 +18,7 @@ const (
 	SizeofSockaddrUnix      = 0x6e
 	SizeofSockaddrLinklayer = 0x14
 	SizeofLinger            = 0x8
+	SizeofIpMreq            = 0x8
 	SizeofMsghdr            = 0x1c
 	SizeofCmsghdr           = 0xc
 	SizeofUcred             = 0xc
@@ -65,17 +66,17 @@ type Timex struct {
 	Errcnt        int32
 	Stbcnt        int32
 	Tai           int32
-	Pad0      int32
-	Pad1      int32
-	Pad2      int32
-	Pad3      int32
-	Pad4      int32
-	Pad5      int32
-	Pad6      int32
-	Pad7      int32
-	Pad8      int32
-	Pad9      int32
-	Pad10     int32
+	Pad_godefs_0  int32
+	Pad_godefs_1  int32
+	Pad_godefs_2  int32
+	Pad_godefs_3  int32
+	Pad_godefs_4  int32
+	Pad_godefs_5  int32
+	Pad_godefs_6  int32
+	Pad_godefs_7  int32
+	Pad_godefs_8  int32
+	Pad_godefs_9  int32
+	Pad_godefs_10 int32
 }
 
 type Time_t int32
@@ -121,7 +122,7 @@ type _Gid_t uint32
 type Stat_t struct {
 	Dev          uint64
 	X__pad1      uint16
-	Pad0      [2]byte
+	Pad_godefs_0 [2]byte
 	X__st_ino    uint32
 	Mode         uint32
 	Nlink        uint32
@@ -129,7 +130,7 @@ type Stat_t struct {
 	Gid          uint32
 	Rdev         uint64
 	X__pad2      uint16
-	Pad1      [2]byte
+	Pad_godefs_1 [2]byte
 	Size         int64
 	Blksize      int32
 	Blocks       int64
@@ -159,7 +160,7 @@ type Dirent struct {
 	Reclen       uint16
 	Type         uint8
 	Name         [256]int8
-	Pad0   [1]byte
+	Pad_godefs_0 [1]byte
 }
 
 type RawSockaddrInet4 struct {
@@ -214,6 +215,11 @@ type Iovec struct {
 	Len  uint32
 }
 
+type IpMreq struct {
+	Multiaddr [4]byte /* in_addr */
+	Interface [4]byte /* in_addr */
+}
+
 type Msghdr struct {
 	Name       *byte
 	Namelen    uint32

src/pkg/syscall/ztypes_linux_amd64.go

@@ -18,6 +18,7 @@ const (
 	SizeofSockaddrUnix      = 0x6e
 	SizeofSockaddrLinklayer = 0x14
 	SizeofLinger            = 0x8
+	SizeofIpMreq            = 0x8
 	SizeofMsghdr            = 0x38
 	SizeofCmsghdr           = 0x10
 	SizeofUcred             = 0xc
@@ -46,13 +47,13 @@ type Timeval struct {
 
 type Timex struct {
 	Modes         uint32
-	Pad0      [4]byte
+	Pad_godefs_0  [4]byte
 	Offset        int64
 	Freq          int64
 	Maxerror      int64
 	Esterror      int64
 	Status        int32
-	Pad1      [4]byte
+	Pad_godefs_1  [4]byte
 	Constant      int64
 	Precision     int64
 	Tolerance     int64
@@ -61,24 +62,24 @@ type Timex struct {
 	Ppsfreq       int64
 	Jitter        int64
 	Shift         int32
-	Pad2      [4]byte
+	Pad_godefs_2  [4]byte
 	Stabil        int64
 	Jitcnt        int64
 	Calcnt        int64
 	Errcnt        int64
 	Stbcnt        int64
 	Tai           int32
-	Pad3      int32
-	Pad4      int32
-	Pad5      int32
-	Pad6      int32
-	Pad7      int32
-	Pad8      int32
-	Pad9      int32
-	Pad10     int32
-	Pad11     int32
-	Pad12     int32
-	Pad13     int32
+	Pad_godefs_3  int32
+	Pad_godefs_4  int32
+	Pad_godefs_5  int32
+	Pad_godefs_6  int32
+	Pad_godefs_7  int32
+	Pad_godefs_8  int32
+	Pad_godefs_9  int32
+	Pad_godefs_10 int32
+	Pad_godefs_11 int32
+	Pad_godefs_12 int32
+	Pad_godefs_13 int32
 }
 
 type Time_t int64
@@ -159,7 +160,7 @@ type Dirent struct {
 	Reclen       uint16
 	Type         uint8
 	Name         [256]int8
-	Pad0   [5]byte
+	Pad_godefs_0 [5]byte
 }
 
 type RawSockaddrInet4 struct {
@@ -214,16 +215,21 @@ type Iovec struct {
 	Len  uint64
 }
 
+type IpMreq struct {
+	Multiaddr [4]byte /* in_addr */
+	Interface [4]byte /* in_addr */
+}
+
 type Msghdr struct {
 	Name         *byte
 	Namelen      uint32
-	Pad0       [4]byte
+	Pad_godefs_0 [4]byte
 	Iov          *Iovec
 	Iovlen       uint64
 	Control      *byte
 	Controllen   uint64
 	Flags        int32
-	Pad1       [4]byte
+	Pad_godefs_1 [4]byte
 }
 
 type Cmsghdr struct {
@@ -290,12 +296,12 @@ type Sysinfo_t struct {
 	Freeswap     uint64
 	Procs        uint16
 	Pad          uint16
-	Pad0      [4]byte
+	Pad_godefs_0 [4]byte
 	Totalhigh    uint64
 	Freehigh     uint64
 	Unit         uint32
-	X_f       [2]int8
-	Pad1      [4]byte
+	X_f          [0]int8
+	Pad_godefs_1 [4]byte
 }
 
 type Utsname struct {
@@ -309,11 +315,11 @@ type Utsname struct {
 
 type Ustat_t struct {
 	Tfree        int32
-	Pad0   [4]byte
+	Pad_godefs_0 [4]byte
 	Tinode       uint64
 	Fname        [6]int8
 	Fpack        [6]int8
-	Pad1   [4]byte
+	Pad_godefs_1 [4]byte
 }
 
 type EpollEvent struct {