unix: add Select on Solaris

Change-Id: I9e0e4bc6b9f8700d72e891d623f948db6af7d64b
Reviewed-on: https://go-review.googlesource.com/85255
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

unix/syscall_solaris.go

@@ -658,6 +658,7 @@ func Poll(fds []PollFd, timeout int) (n int, err error) {
 //sys	Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error)
 //sys	Rmdir(path string) (err error)
 //sys	Seek(fd int, offset int64, whence int) (newoffset int64, err error) = lseek
+//sys	Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error)
 //sysnb	Setegid(egid int) (err error)
 //sysnb	Seteuid(euid int) (err error)
 //sysnb	Setgid(gid int) (err error)

unix/syscall_solaris_test.go

@@ -9,10 +9,31 @@ package unix_test
 import (
 	"os/exec"
 	"testing"
+	"time"
 
 	"golang.org/x/sys/unix"
 )
 
+func TestSelect(t *testing.T) {
+	err := unix.Select(0, nil, nil, nil, &unix.Timeval{Sec: 0, Usec: 0})
+	if err != nil {
+		t.Fatalf("Select: %v", err)
+	}
+
+	dur := 150 * time.Millisecond
+	tv := unix.NsecToTimeval(int64(dur))
+	start := time.Now()
+	err = unix.Select(0, nil, nil, nil, &tv)
+	took := time.Since(start)
+	if err != nil {
+		t.Fatalf("Select: %v", err)
+	}
+
+	if took < dur {
+		t.Errorf("Select: timeout should have been at least %v, got %v", dur, took)
+	}
+}
+
 func TestStatvfs(t *testing.T) {
 	if err := unix.Statvfs("", nil); err == nil {
 		t.Fatal(`Statvfs("") expected failure`)

unix/zsyscall_solaris_amd64.go

@@ -95,6 +95,7 @@ import (
 //go:cgo_import_dynamic libc_renameat renameat "libc.so"
 //go:cgo_import_dynamic libc_rmdir rmdir "libc.so"
 //go:cgo_import_dynamic libc_lseek lseek "libc.so"
+//go:cgo_import_dynamic libc_select select "libc.so"
 //go:cgo_import_dynamic libc_setegid setegid "libc.so"
 //go:cgo_import_dynamic libc_seteuid seteuid "libc.so"
 //go:cgo_import_dynamic libc_setgid setgid "libc.so"
@@ -220,6 +221,7 @@ import (
 //go:linkname procRenameat libc_renameat
 //go:linkname procRmdir libc_rmdir
 //go:linkname proclseek libc_lseek
+//go:linkname procSelect libc_select
 //go:linkname procSetegid libc_setegid
 //go:linkname procSeteuid libc_seteuid
 //go:linkname procSetgid libc_setgid
@@ -346,6 +348,7 @@ var (
 	procRenameat,
 	procRmdir,
 	proclseek,
+	procSelect,
 	procSetegid,
 	procSeteuid,
 	procSetgid,
@@ -1264,6 +1267,14 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
 	return
 }
 
+func Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error) {
+	_, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procSelect)), 5, uintptr(n), uintptr(unsafe.Pointer(r)), uintptr(unsafe.Pointer(w)), uintptr(unsafe.Pointer(e)), uintptr(unsafe.Pointer(timeout)), 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
 func Setegid(egid int) (err error) {
 	_, _, e1 := rawSysvicall6(uintptr(unsafe.Pointer(&procSetegid)), 1, uintptr(egid), 0, 0, 0, 0, 0)
 	if e1 != 0 {