unix: add Poll function on Solaris

Tested with TestPoll extracted from syscall_linux_test.go.

Now that Poll is supported on all unix flavors, TestPoll can be moved
to syscall_unix_test.go in a successive CL.

Change-Id: Ibd5ff3f45198008464522c3b165f2af7865ce81e
Reviewed-on: https://go-review.googlesource.com/73881
Reviewed-by: Ian Lance Taylor <iant@golang.org>

unix/syscall_solaris.go

@@ -578,6 +578,15 @@ func IoctlGetTermio(fd int, req uint) (*Termio, error) {
 	return &value, err
 }
 
+//sys   poll(fds *PollFd, nfds int, timeout int) (n int, err error)
+
+func Poll(fds []PollFd, timeout int) (n int, err error) {
+	if len(fds) == 0 {
+		return poll(nil, 0, timeout)
+	}
+	return poll(&fds[0], len(fds), timeout)
+}
+
 /*
  * Exposed directly
  */

unix/types_solaris.go

@@ -24,6 +24,7 @@ package unix
 #include <fcntl.h>
 #include <netdb.h>
 #include <limits.h>
+#include <poll.h>
 #include <signal.h>
 #include <termios.h>
 #include <termio.h>
@@ -263,3 +264,20 @@ type Termios C.struct_termios
 type Termio C.struct_termio
 
 type Winsize C.struct_winsize
+
+// poll
+
+type PollFd C.struct_pollfd
+
+const (
+	POLLERR    = C.POLLERR
+	POLLHUP    = C.POLLHUP
+	POLLIN     = C.POLLIN
+	POLLNVAL   = C.POLLNVAL
+	POLLOUT    = C.POLLOUT
+	POLLPRI    = C.POLLPRI
+	POLLRDBAND = C.POLLRDBAND
+	POLLRDNORM = C.POLLRDNORM
+	POLLWRBAND = C.POLLWRBAND
+	POLLWRNORM = C.POLLWRNORM
+)

unix/zsyscall_solaris_amd64.go

@@ -29,6 +29,7 @@ import (
 //go:cgo_import_dynamic libc___major __major "libc.so"
 //go:cgo_import_dynamic libc___minor __minor "libc.so"
 //go:cgo_import_dynamic libc_ioctl ioctl "libc.so"
+//go:cgo_import_dynamic libc_poll poll "libc.so"
 //go:cgo_import_dynamic libc_access access "libc.so"
 //go:cgo_import_dynamic libc_adjtime adjtime "libc.so"
 //go:cgo_import_dynamic libc_chdir chdir "libc.so"
@@ -153,6 +154,7 @@ import (
 //go:linkname proc__major libc___major
 //go:linkname proc__minor libc___minor
 //go:linkname procioctl libc_ioctl
+//go:linkname procpoll libc_poll
 //go:linkname procAccess libc_access
 //go:linkname procAdjtime libc_adjtime
 //go:linkname procChdir libc_chdir
@@ -278,6 +280,7 @@ var (
 	proc__major,
 	proc__minor,
 	procioctl,
+	procpoll,
 	procAccess,
 	procAdjtime,
 	procChdir,
@@ -557,6 +560,15 @@ func ioctl(fd int, req uint, arg uintptr) (err error) {
 	return
 }
 
+func poll(fds *PollFd, nfds int, timeout int) (n int, err error) {
+	r0, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procpoll)), 3, uintptr(unsafe.Pointer(fds)), uintptr(nfds), uintptr(timeout), 0, 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
 func Access(path string, mode uint32) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

unix/ztypes_solaris_amd64.go

@@ -438,3 +438,22 @@ type Winsize struct {
 	Xpixel uint16
 	Ypixel uint16
 }
+
+type PollFd struct {
+	Fd      int32
+	Events  int16
+	Revents int16
+}
+
+const (
+	POLLERR    = 0x8
+	POLLHUP    = 0x10
+	POLLIN     = 0x1
+	POLLNVAL   = 0x20
+	POLLOUT    = 0x4
+	POLLPRI    = 0x2
+	POLLRDBAND = 0x80
+	POLLRDNORM = 0x40
+	POLLWRBAND = 0x100
+	POLLWRNORM = 0x4
+)