unix: create wrappers for solaris/illumos Event Ports
This work is in support of a cleanup of fsnotify/fsnotify#263
Change-Id: Ibd7500d20322765bfd50aa18333eb43ee7b659d7
Reviewed-on: https://go-review.googlesource.com/c/sys/+/324630
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
diff --git a/unix/syscall_solaris.go b/unix/syscall_solaris.go
index 77fcde7..d2a6495 100644
--- a/unix/syscall_solaris.go
+++ b/unix/syscall_solaris.go
@@ -13,7 +13,10 @@
package unix
import (
+ "fmt"
+ "os"
"runtime"
+ "sync"
"syscall"
"unsafe"
)
@@ -744,3 +747,240 @@
func Munmap(b []byte) (err error) {
return mapper.Munmap(b)
}
+
+// Event Ports
+
+type fileObjCookie struct {
+ fobj *fileObj
+ cookie interface{}
+}
+
+// EventPort provides a safe abstraction on top of Solaris/illumos Event Ports.
+type EventPort struct {
+ port int
+ mu sync.Mutex
+ fds map[uintptr]interface{}
+ paths map[string]*fileObjCookie
+}
+
+// PortEvent is an abstraction of the port_event C struct.
+// Compare Source against PORT_SOURCE_FILE or PORT_SOURCE_FD
+// to see if Path or Fd was the event source. The other will be
+// uninitialized.
+type PortEvent struct {
+ Cookie interface{}
+ Events int32
+ Fd uintptr
+ Path string
+ Source uint16
+ fobj *fileObj
+}
+
+// NewEventPort creates a new EventPort including the
+// underlying call to port_create(3c).
+func NewEventPort() (*EventPort, error) {
+ port, err := port_create()
+ if err != nil {
+ return nil, err
+ }
+ e := &EventPort{
+ port: port,
+ fds: make(map[uintptr]interface{}),
+ paths: make(map[string]*fileObjCookie),
+ }
+ return e, nil
+}
+
+//sys port_create() (n int, err error)
+//sys port_associate(port int, source int, object uintptr, events int, user *byte) (n int, err error)
+//sys port_dissociate(port int, source int, object uintptr) (n int, err error)
+//sys port_get(port int, pe *portEvent, timeout *Timespec) (n int, err error)
+//sys port_getn(port int, pe *portEvent, max uint32, nget *uint32, timeout *Timespec) (n int, err error)
+
+// Close closes the event port.
+func (e *EventPort) Close() error {
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ e.fds = nil
+ e.paths = nil
+ return Close(e.port)
+}
+
+// PathIsWatched checks to see if path is associated with this EventPort.
+func (e *EventPort) PathIsWatched(path string) bool {
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ _, found := e.paths[path]
+ return found
+}
+
+// FdIsWatched checks to see if fd is associated with this EventPort.
+func (e *EventPort) FdIsWatched(fd uintptr) bool {
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ _, found := e.fds[fd]
+ return found
+}
+
+// AssociatePath wraps port_associate(3c) for a filesystem path including
+// creating the necessary file_obj from the provided stat information.
+func (e *EventPort) AssociatePath(path string, stat os.FileInfo, events int, cookie interface{}) error {
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ if _, found := e.paths[path]; found {
+ return fmt.Errorf("%v is already associated with this Event Port", path)
+ }
+ fobj, err := createFileObj(path, stat)
+ if err != nil {
+ return err
+ }
+ fCookie := &fileObjCookie{fobj, cookie}
+ _, err = port_associate(e.port, PORT_SOURCE_FILE, uintptr(unsafe.Pointer(fobj)), events, (*byte)(unsafe.Pointer(&fCookie.cookie)))
+ if err != nil {
+ return err
+ }
+ e.paths[path] = fCookie
+ return nil
+}
+
+// DissociatePath wraps port_dissociate(3c) for a filesystem path.
+func (e *EventPort) DissociatePath(path string) error {
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ f, ok := e.paths[path]
+ if !ok {
+ return fmt.Errorf("%v is not associated with this Event Port", path)
+ }
+ _, err := port_dissociate(e.port, PORT_SOURCE_FILE, uintptr(unsafe.Pointer(f.fobj)))
+ if err != nil {
+ return err
+ }
+ delete(e.paths, path)
+ return nil
+}
+
+// AssociateFd wraps calls to port_associate(3c) on file descriptors.
+func (e *EventPort) AssociateFd(fd uintptr, events int, cookie interface{}) error {
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ if _, found := e.fds[fd]; found {
+ return fmt.Errorf("%v is already associated with this Event Port", fd)
+ }
+ pcookie := &cookie
+ _, err := port_associate(e.port, PORT_SOURCE_FD, fd, events, (*byte)(unsafe.Pointer(pcookie)))
+ if err != nil {
+ return err
+ }
+ e.fds[fd] = pcookie
+ return nil
+}
+
+// DissociateFd wraps calls to port_dissociate(3c) on file descriptors.
+func (e *EventPort) DissociateFd(fd uintptr) error {
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ _, ok := e.fds[fd]
+ if !ok {
+ return fmt.Errorf("%v is not associated with this Event Port", fd)
+ }
+ _, err := port_dissociate(e.port, PORT_SOURCE_FD, fd)
+ if err != nil {
+ return err
+ }
+ delete(e.fds, fd)
+ return nil
+}
+
+func createFileObj(name string, stat os.FileInfo) (*fileObj, error) {
+ fobj := new(fileObj)
+ bs, err := ByteSliceFromString(name)
+ if err != nil {
+ return nil, err
+ }
+ fobj.Name = (*int8)(unsafe.Pointer(&bs[0]))
+ s := stat.Sys().(*syscall.Stat_t)
+ fobj.Atim.Sec = s.Atim.Sec
+ fobj.Atim.Nsec = s.Atim.Nsec
+ fobj.Mtim.Sec = s.Mtim.Sec
+ fobj.Mtim.Nsec = s.Mtim.Nsec
+ fobj.Ctim.Sec = s.Ctim.Sec
+ fobj.Ctim.Nsec = s.Ctim.Nsec
+ return fobj, nil
+}
+
+// GetOne wraps port_get(3c) and returns a single PortEvent.
+func (e *EventPort) GetOne(t *Timespec) (*PortEvent, error) {
+ pe := new(portEvent)
+ _, err := port_get(e.port, pe, t)
+ if err != nil {
+ return nil, err
+ }
+ p := new(PortEvent)
+ p.Events = pe.Events
+ p.Source = pe.Source
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ switch pe.Source {
+ case PORT_SOURCE_FD:
+ p.Fd = uintptr(pe.Object)
+ cookie := (*interface{})(unsafe.Pointer(pe.User))
+ p.Cookie = *cookie
+ delete(e.fds, p.Fd)
+ case PORT_SOURCE_FILE:
+ p.fobj = (*fileObj)(unsafe.Pointer(uintptr(pe.Object)))
+ p.Path = BytePtrToString((*byte)(unsafe.Pointer(p.fobj.Name)))
+ cookie := (*interface{})(unsafe.Pointer(pe.User))
+ p.Cookie = *cookie
+ delete(e.paths, p.Path)
+ }
+ return p, nil
+}
+
+// Pending wraps port_getn(3c) and returns how many events are pending.
+func (e *EventPort) Pending() (int, error) {
+ var n uint32 = 0
+ _, err := port_getn(e.port, nil, 0, &n, nil)
+ return int(n), err
+}
+
+// Get wraps port_getn(3c) and fills a slice of PortEvent.
+// It will block until either min events have been received
+// or the timeout has been exceeded. It will return how many
+// events were actually received along with any error information.
+func (e *EventPort) Get(s []PortEvent, min int, timeout *Timespec) (int, error) {
+ if min == 0 {
+ return 0, fmt.Errorf("need to request at least one event or use Pending() instead")
+ }
+ if len(s) < min {
+ return 0, fmt.Errorf("len(s) (%d) is less than min events requested (%d)", len(s), min)
+ }
+ got := uint32(min)
+ max := uint32(len(s))
+ var err error
+ ps := make([]portEvent, max, max)
+ _, err = port_getn(e.port, &ps[0], max, &got, timeout)
+ // got will be trustworthy with ETIME, but not any other error.
+ if err != nil && err != ETIME {
+ return 0, err
+ }
+ e.mu.Lock()
+ defer e.mu.Unlock()
+ for i := 0; i < int(got); i++ {
+ s[i].Events = ps[i].Events
+ s[i].Source = ps[i].Source
+ switch ps[i].Source {
+ case PORT_SOURCE_FD:
+ s[i].Fd = uintptr(ps[i].Object)
+ cookie := (*interface{})(unsafe.Pointer(ps[i].User))
+ s[i].Cookie = *cookie
+ delete(e.fds, s[i].Fd)
+ case PORT_SOURCE_FILE:
+ s[i].fobj = (*fileObj)(unsafe.Pointer(uintptr(ps[i].Object)))
+ s[i].Path = BytePtrToString((*byte)(unsafe.Pointer(s[i].fobj.Name)))
+ cookie := (*interface{})(unsafe.Pointer(ps[i].User))
+ s[i].Cookie = *cookie
+ delete(e.paths, s[i].Path)
+ }
+ }
+ return int(got), err
+}
diff --git a/unix/syscall_solaris_test.go b/unix/syscall_solaris_test.go
index 910bdf1..c2b28be 100644
--- a/unix/syscall_solaris_test.go
+++ b/unix/syscall_solaris_test.go
@@ -8,7 +8,11 @@
package unix_test
import (
+ "fmt"
+ "io/ioutil"
+ "os"
"os/exec"
+ "runtime"
"testing"
"golang.org/x/sys/unix"
@@ -41,3 +45,290 @@
}
t.Logf("Sysconf(SC_CLK_TCK) = %d", n)
}
+
+// Event Ports
+
+func TestBasicEventPort(t *testing.T) {
+ tmpfile, err := ioutil.TempFile("", "eventport")
+ if err != nil {
+ t.Fatalf("unable to create a tempfile: %v", err)
+ }
+ path := tmpfile.Name()
+ defer os.Remove(path)
+
+ stat, err := os.Stat(path)
+ if err != nil {
+ t.Fatalf("Failed to stat %s: %v", path, err)
+ }
+ port, err := unix.NewEventPort()
+ if err != nil {
+ t.Fatalf("NewEventPort failed: %v", err)
+ }
+ defer port.Close()
+ cookie := stat.Mode()
+ err = port.AssociatePath(path, stat, unix.FILE_MODIFIED, cookie)
+ if err != nil {
+ t.Errorf("AssociatePath failed: %v", err)
+ }
+ if !port.PathIsWatched(path) {
+ t.Errorf("PathIsWatched unexpectedly returned false")
+ }
+ err = port.DissociatePath(path)
+ if err != nil {
+ t.Errorf("DissociatePath failed: %v", err)
+ }
+ err = port.AssociatePath(path, stat, unix.FILE_MODIFIED, cookie)
+ if err != nil {
+ t.Errorf("AssociatePath failed: %v", err)
+ }
+ bs := []byte{42}
+ tmpfile.Write(bs)
+ timeout := new(unix.Timespec)
+ timeout.Sec = 1
+ pevent, err := port.GetOne(timeout)
+ if err == unix.ETIME {
+ t.Errorf("GetOne timed out: %v", err)
+ }
+ if err != nil {
+ t.Errorf("GetOne failed: %v", err)
+ }
+ if pevent.Path != path {
+ t.Errorf("Path mismatch: %v != %v", pevent.Path, path)
+ }
+ err = port.AssociatePath(path, stat, unix.FILE_MODIFIED, cookie)
+ if err != nil {
+ t.Errorf("AssociatePath failed: %v", err)
+ }
+ err = port.AssociatePath(path, stat, unix.FILE_MODIFIED, cookie)
+ if err == nil {
+ t.Errorf("Unexpected success associating already associated path")
+ }
+}
+
+func TestEventPortFds(t *testing.T) {
+ _, path, _, _ := runtime.Caller(0)
+ stat, err := os.Stat(path)
+ cookie := stat.Mode()
+ port, err := unix.NewEventPort()
+ if err != nil {
+ t.Errorf("NewEventPort failed: %v", err)
+ }
+ defer port.Close()
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Errorf("unable to create a pipe: %v", err)
+ }
+ defer w.Close()
+ defer r.Close()
+ fd := r.Fd()
+
+ port.AssociateFd(fd, unix.POLLIN, cookie)
+ if !port.FdIsWatched(fd) {
+ t.Errorf("FdIsWatched unexpectedly returned false")
+ }
+ err = port.DissociateFd(fd)
+ err = port.AssociateFd(fd, unix.POLLIN, cookie)
+ bs := []byte{42}
+ w.Write(bs)
+ n, err := port.Pending()
+ if n != 1 {
+ t.Errorf("Pending() failed: %v, %v", n, err)
+ }
+ timeout := new(unix.Timespec)
+ timeout.Sec = 1
+ pevent, err := port.GetOne(timeout)
+ if err == unix.ETIME {
+ t.Errorf("GetOne timed out: %v", err)
+ }
+ if err != nil {
+ t.Errorf("GetOne failed: %v", err)
+ }
+ if pevent.Fd != fd {
+ t.Errorf("Fd mismatch: %v != %v", pevent.Fd, fd)
+ }
+ var c = pevent.Cookie
+ if c == nil {
+ t.Errorf("Cookie missing: %v != %v", cookie, c)
+ return
+ }
+ if c != cookie {
+ t.Errorf("Cookie mismatch: %v != %v", cookie, c)
+ }
+ port.AssociateFd(fd, unix.POLLIN, cookie)
+ err = port.AssociateFd(fd, unix.POLLIN, cookie)
+ if err == nil {
+ t.Errorf("unexpected success associating already associated fd")
+ }
+}
+
+func TestEventPortErrors(t *testing.T) {
+ tmpfile, err := ioutil.TempFile("", "eventport")
+ if err != nil {
+ t.Errorf("unable to create a tempfile: %v", err)
+ }
+ path := tmpfile.Name()
+ stat, _ := os.Stat(path)
+ os.Remove(path)
+ port, _ := unix.NewEventPort()
+ defer port.Close()
+ err = port.AssociatePath(path, stat, unix.FILE_MODIFIED, nil)
+ if err == nil {
+ t.Errorf("unexpected success associating nonexistant file")
+ }
+ err = port.DissociatePath(path)
+ if err == nil {
+ t.Errorf("unexpected success dissociating unassociated path")
+ }
+ timeout := new(unix.Timespec)
+ timeout.Nsec = 1
+ _, err = port.GetOne(timeout)
+ if err != unix.ETIME {
+ t.Errorf("unexpected lack of timeout")
+ }
+ err = port.DissociateFd(uintptr(0))
+ if err == nil {
+ t.Errorf("unexpected success dissociating unassociated fd")
+ }
+ events := make([]unix.PortEvent, 4, 4)
+ _, err = port.Get(events, 5, nil)
+ if err == nil {
+ t.Errorf("unexpected success calling Get with min greater than len of slice")
+ }
+ _, err = port.Get(nil, 1, nil)
+ if err == nil {
+ t.Errorf("unexpected success calling Get with nil slice")
+ }
+ _, err = port.Get(nil, 0, nil)
+ if err == nil {
+ t.Errorf("unexpected success calling Get with nil slice")
+ }
+}
+
+func ExamplePortEvent() {
+ type MyCookie struct {
+ Name string
+ }
+ cookie := MyCookie{"Cookie Monster"}
+ port, err := unix.NewEventPort()
+ if err != nil {
+ fmt.Printf("NewEventPort failed: %v\n", err)
+ return
+ }
+ defer port.Close()
+ r, w, err := os.Pipe()
+ if err != nil {
+ fmt.Printf("os.Pipe() failed: %v\n", err)
+ return
+ }
+ defer w.Close()
+ defer r.Close()
+ fd := r.Fd()
+
+ port.AssociateFd(fd, unix.POLLIN, cookie)
+
+ bs := []byte{42}
+ w.Write(bs)
+ timeout := new(unix.Timespec)
+ timeout.Sec = 1
+ pevent, err := port.GetOne(timeout)
+ if err != nil {
+ fmt.Printf("didn't get the expected event: %v\n", err)
+ }
+
+ // Use a type assertion to convert the received cookie back to its original type
+ c := pevent.Cookie.(MyCookie)
+ fmt.Printf("%s", c.Name)
+ //Output: Cookie Monster
+}
+
+func TestPortEventSlices(t *testing.T) {
+ port, err := unix.NewEventPort()
+ if err != nil {
+ t.Fatalf("NewEventPort failed: %v", err)
+ }
+ // Create, associate, and delete 6 files
+ for i := 0; i < 6; i++ {
+ tmpfile, err := ioutil.TempFile("", "eventport")
+ if err != nil {
+ t.Fatalf("unable to create tempfile: %v", err)
+ }
+ path := tmpfile.Name()
+ stat, err := os.Stat(path)
+ if err != nil {
+ t.Fatalf("unable to stat tempfile: %v", err)
+ }
+ err = port.AssociatePath(path, stat, unix.FILE_MODIFIED, nil)
+ if err != nil {
+ t.Fatalf("unable to AssociatePath tempfile: %v", err)
+ }
+ err = os.Remove(path)
+ if err != nil {
+ t.Fatalf("unable to Remove tempfile: %v", err)
+ }
+ }
+ n, err := port.Pending()
+ if err != nil {
+ t.Errorf("Pending failed: %v", err)
+ }
+ if n != 6 {
+ t.Errorf("expected 6 pending events, got %d", n)
+ }
+ timeout := new(unix.Timespec)
+ timeout.Nsec = 1
+ events := make([]unix.PortEvent, 4, 4)
+ n, err = port.Get(events, 3, timeout)
+ if err != nil {
+ t.Errorf("Get failed: %v", err)
+ }
+ if n != 4 {
+ t.Errorf("expected 4 events, got %d", n)
+ }
+ e := events[:n]
+ for _, p := range e {
+ if p.Events != unix.FILE_DELETE {
+ t.Errorf("unexpected event. got %v, expected %v", p.Events, unix.FILE_DELETE)
+ }
+ }
+ n, err = port.Get(events, 3, timeout)
+ if err != unix.ETIME {
+ t.Errorf("unexpected error. got %v, expected %v", err, unix.ETIME)
+ }
+ if n != 2 {
+ t.Errorf("expected 2 events, got %d", n)
+ }
+ e = events[:n]
+ for _, p := range e {
+ if p.Events != unix.FILE_DELETE {
+ t.Errorf("unexpected event. got %v, expected %v", p.Events, unix.FILE_DELETE)
+ }
+ }
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatalf("unable to create a pipe: %v", err)
+ }
+ port.AssociateFd(r.Fd(), unix.POLLIN, nil)
+ port.AssociateFd(w.Fd(), unix.POLLOUT, nil)
+ bs := []byte{41}
+ w.Write(bs)
+
+ n, err = port.Get(events, 1, timeout)
+ if err != nil {
+ t.Errorf("Get failed: %v", err)
+ }
+ if n != 2 {
+ t.Errorf("expected 2 events, got %d", n)
+ }
+ err = w.Close()
+ if err != nil {
+ t.Errorf("w.Close() failed: %v", err)
+ }
+ err = r.Close()
+ if err != nil {
+ t.Errorf("r.Close() failed: %v", err)
+ }
+ err = port.Close()
+ if err != nil {
+ t.Errorf("port.Close() failed: %v", err)
+ }
+}
diff --git a/unix/zsyscall_solaris_amd64.go b/unix/zsyscall_solaris_amd64.go
index 4e18d5c..b5f926c 100644
--- a/unix/zsyscall_solaris_amd64.go
+++ b/unix/zsyscall_solaris_amd64.go
@@ -141,6 +141,11 @@
//go:cgo_import_dynamic libc_getpeername getpeername "libsocket.so"
//go:cgo_import_dynamic libc_setsockopt setsockopt "libsocket.so"
//go:cgo_import_dynamic libc_recvfrom recvfrom "libsocket.so"
+//go:cgo_import_dynamic libc_port_create port_create "libc.so"
+//go:cgo_import_dynamic libc_port_associate port_associate "libc.so"
+//go:cgo_import_dynamic libc_port_dissociate port_dissociate "libc.so"
+//go:cgo_import_dynamic libc_port_get port_get "libc.so"
+//go:cgo_import_dynamic libc_port_getn port_getn "libc.so"
//go:linkname procpipe libc_pipe
//go:linkname procpipe2 libc_pipe2
@@ -272,6 +277,11 @@
//go:linkname procgetpeername libc_getpeername
//go:linkname procsetsockopt libc_setsockopt
//go:linkname procrecvfrom libc_recvfrom
+//go:linkname procport_create libc_port_create
+//go:linkname procport_associate libc_port_associate
+//go:linkname procport_dissociate libc_port_dissociate
+//go:linkname procport_get libc_port_get
+//go:linkname procport_getn libc_port_getn
var (
procpipe,
@@ -403,7 +413,12 @@
proc__xnet_getsockopt,
procgetpeername,
procsetsockopt,
- procrecvfrom syscallFunc
+ procrecvfrom,
+ procport_create,
+ procport_associate,
+ procport_dissociate,
+ procport_get,
+ procport_getn syscallFunc
)
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
@@ -1981,3 +1996,58 @@
}
return
}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func port_create() (n int, err error) {
+ r0, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procport_create)), 0, 0, 0, 0, 0, 0, 0)
+ n = int(r0)
+ if e1 != 0 {
+ err = e1
+ }
+ return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func port_associate(port int, source int, object uintptr, events int, user *byte) (n int, err error) {
+ r0, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procport_associate)), 5, uintptr(port), uintptr(source), uintptr(object), uintptr(events), uintptr(unsafe.Pointer(user)), 0)
+ n = int(r0)
+ if e1 != 0 {
+ err = e1
+ }
+ return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func port_dissociate(port int, source int, object uintptr) (n int, err error) {
+ r0, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procport_dissociate)), 3, uintptr(port), uintptr(source), uintptr(object), 0, 0, 0)
+ n = int(r0)
+ if e1 != 0 {
+ err = e1
+ }
+ return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func port_get(port int, pe *portEvent, timeout *Timespec) (n int, err error) {
+ r0, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procport_get)), 3, uintptr(port), uintptr(unsafe.Pointer(pe)), uintptr(unsafe.Pointer(timeout)), 0, 0, 0)
+ n = int(r0)
+ if e1 != 0 {
+ err = e1
+ }
+ return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func port_getn(port int, pe *portEvent, max uint32, nget *uint32, timeout *Timespec) (n int, err error) {
+ r0, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procport_getn)), 5, uintptr(port), uintptr(unsafe.Pointer(pe)), uintptr(max), uintptr(unsafe.Pointer(nget)), uintptr(unsafe.Pointer(timeout)), 0)
+ n = int(r0)
+ if e1 != 0 {
+ err = e1
+ }
+ return
+}
