all: drop support for FreeBSD 9 or below

This change drops the support for FreeBSD 9 or below and simplifies
platform-dependent code for the sake of maintenance.

Updates #7187.
Fixes #11412.
Updates #16064.
Updates #18854.
Fixes #19072.

Change-Id: I9129130aafbfc7d0d7e9b674b6fc6cb31b7381be
Reviewed-on: https://go-review.googlesource.com/64910Reviewed-by: Ian Lance Taylor <iant@golang.org>

doc/install.html

@@ -16,7 +16,7 @@
 
 <p>
 <a href="https://golang.org/dl/" target="_blank">Official binary
-distributions</a> are available for the FreeBSD (release 8-STABLE and above),
+distributions</a> are available for the FreeBSD (release 10-STABLE and above),
 Linux, Mac OS X (10.8 and above), and Windows operating systems and
 the 32-bit (<code>386</code>) and 64-bit (<code>amd64</code>) x86 processor
 architectures.
@@ -47,7 +47,7 @@ If your OS or architecture is not on the list, you may be able to
 <th align="center">Notes</th>
 </tr>
 <tr><td colspan="3"><hr></td></tr>
-<tr><td>FreeBSD 9.3 or later</td> <td>amd64, 386</td> <td>Debian GNU/kFreeBSD not supported</td></tr>
+<tr><td>FreeBSD 10.3 or later</td> <td>amd64, 386</td> <td>Debian GNU/kFreeBSD not supported</td></tr>
 <tr valign='top'><td>Linux 2.6.23 or later with glibc</td> <td>amd64, 386, arm, arm64,<br>s390x, ppc64le</td> <td>CentOS/RHEL 5.x not supported.<br>Install from source for other libc.</td></tr>
 <tr><td>macOS 10.8 or later</td> <td>amd64</td> <td>use the clang or gcc<sup>&#8224;</sup> that comes with Xcode<sup>&#8225;</sup> for <code>cgo</code> support</td></tr>
 <tr><td>Windows XP SP2 or later</td> <td>amd64, 386</td> <td>use MinGW gcc<sup>&#8224;</sup>. No need for cygwin or msys.</td></tr>

src/net/platform_test.go

@@ -43,8 +43,6 @@ func testableNetwork(network string) bool {
 	case "unixpacket":
 		switch runtime.GOOS {
 		case "android", "darwin", "nacl", "plan9", "windows":
-			fallthrough
-		case "freebsd": // FreeBSD 8 and below don't support unixpacket
 			return false
 		}
 	}

src/net/sock_bsd.go

@@ -17,8 +17,10 @@ func maxListenerBacklog() int {
 		err error
 	)
 	switch runtime.GOOS {
-	case "darwin", "freebsd":
+	case "darwin":
 		n, err = syscall.SysctlUint32("kern.ipc.somaxconn")
+	case "freebsd":
+		n, err = syscall.SysctlUint32("kern.ipc.acceptqueue")
 	case "netbsd":
 		// NOTE: NetBSD has no somaxconn-like kernel state so far
 	case "openbsd":

src/os/pipe_freebsd.go

@@ -13,21 +13,7 @@ func Pipe() (r *File, w *File, err error) {
 
 	e := syscall.Pipe2(p[0:], syscall.O_CLOEXEC)
 	if e != nil {
-		// Fallback support for FreeBSD 9, which lacks Pipe2.
-		//
-		// TODO: remove this for Go 1.10 when FreeBSD 9
-		// is removed (Issue 19072).
-
-		// See ../syscall/exec.go for description of lock.
-		syscall.ForkLock.RLock()
-		e := syscall.Pipe(p[0:])
-		if e != nil {
-			syscall.ForkLock.RUnlock()
-			return nil, nil, NewSyscallError("pipe", e)
-		}
-		syscall.CloseOnExec(p[0])
-		syscall.CloseOnExec(p[1])
-		syscall.ForkLock.RUnlock()
+		return nil, nil, NewSyscallError("pipe", e)
 	}
 
 	return newFile(uintptr(p[0]), "|0", kindPipe), newFile(uintptr(p[1]), "|1", kindPipe), nil

src/os/sys_freebsd.go

@@ -4,20 +4,7 @@
 
 package os
 
-import "syscall"
-
 // supportsCloseOnExec reports whether the platform supports the
 // O_CLOEXEC flag.
-var supportsCloseOnExec bool
-
-func init() {
-	osrel, err := syscall.SysctlUint32("kern.osreldate")
-	if err != nil {
-		return
-	}
-	// The O_CLOEXEC flag was introduced in FreeBSD 8.3.
-	// See http://www.freebsd.org/doc/en/books/porters-handbook/freebsd-versions.html.
-	if osrel >= 803000 {
-		supportsCloseOnExec = true
-	}
-}
+// The O_CLOEXEC flag was introduced in FreeBSD 8.3.
+const supportsCloseOnExec bool = true

src/os/wait_wait6.go

@@ -30,11 +30,6 @@ func (p *Process) blockUntilWaitable() (bool, error) {
 	}
 	runtime.KeepAlive(p)
 	if errno != 0 {
-		// The wait6 system call is supported only on FreeBSD
-		// 9.3 and above, so it may return an ENOSYS error.
-		if errno == syscall.ENOSYS {
-			return false, nil
-		}
 		return false, NewSyscallError("wait6", errno)
 	}
 	return true, nil

src/syscall/exec_freebsd.go

@@ -5,21 +5,5 @@
 package syscall
 
 func forkExecPipe(p []int) error {
-	err := Pipe2(p, O_CLOEXEC)
-	if err == nil {
-		return nil
-	}
-
-	// FreeBSD 9 fallback.
-	// TODO: remove this for Go 1.10 per Issue 19072
-	err = Pipe(p)
-	if err != nil {
-		return err
-	}
-	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
-	if err != nil {
-		return err
-	}
-	_, err = fcntl(p[1], F_SETFD, FD_CLOEXEC)
-	return err
+	return Pipe2(p, O_CLOEXEC)
 }

src/syscall/syscall_freebsd.go

@@ -66,15 +66,8 @@ func direntNamlen(buf []byte) (uint64, bool) {
 	return readInt(buf, unsafe.Offsetof(Dirent{}.Namlen), unsafe.Sizeof(Dirent{}.Namlen))
 }
 
-//sysnb pipe() (r int, w int, err error)
-
 func Pipe(p []int) error {
-	if len(p) != 2 {
-		return EINVAL
-	}
-	var err error
-	p[0], p[1], err = pipe()
-	return err
+	return Pipe2(p, 0)
 }
 
 //sysnb pipe2(p *[2]_C_int, flags int) (err error)

src/syscall/zsyscall_freebsd_386.go

@@ -261,18 +261,6 @@ func fcntl(fd int, cmd int, arg int) (val int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe() (r int, w int, err error) {
-	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
-	r = int(r0)
-	w = int(r1)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func pipe2(p *[2]_C_int, flags int) (err error) {
 	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
 	if e1 != 0 {

src/syscall/zsyscall_freebsd_amd64.go

@@ -261,18 +261,6 @@ func fcntl(fd int, cmd int, arg int) (val int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe() (r int, w int, err error) {
-	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
-	r = int(r0)
-	w = int(r1)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func pipe2(p *[2]_C_int, flags int) (err error) {
 	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
 	if e1 != 0 {

src/syscall/zsyscall_freebsd_arm.go

@@ -261,18 +261,6 @@ func fcntl(fd int, cmd int, arg int) (val int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe() (r int, w int, err error) {
-	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
-	r = int(r0)
-	w = int(r1)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func pipe2(p *[2]_C_int, flags int) (err error) {
 	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
 	if e1 != 0 {