replace zxq.co/ripple/hanayo

vendor/github.com/rjeczalik/notify/watcher_fsevents_cgo.go

@@ -0,0 +1,193 @@
+// Copyright (c) 2014-2015 The Notify Authors. All rights reserved.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+// +build darwin,!kqueue
+
+package notify
+
+/*
+#include <CoreServices/CoreServices.h>
+
+typedef void (*CFRunLoopPerformCallBack)(void*);
+
+void gosource(void *);
+void gostream(uintptr_t, uintptr_t, size_t, uintptr_t, uintptr_t, uintptr_t);
+
+static FSEventStreamRef EventStreamCreate(FSEventStreamContext * context, uintptr_t info, CFArrayRef paths, FSEventStreamEventId since, CFTimeInterval latency, FSEventStreamCreateFlags flags) {
+	context->info = (void*) info;
+	return FSEventStreamCreate(NULL, (FSEventStreamCallback) gostream, context, paths, since, latency, flags);
+}
+
+#cgo LDFLAGS: -framework CoreServices
+*/
+import "C"
+
+import (
+	"errors"
+	"os"
+	"runtime"
+	"sync"
+	"sync/atomic"
+	"unsafe"
+)
+
+var nilstream C.FSEventStreamRef
+
+// Default arguments for FSEventStreamCreate function.
+var (
+	latency C.CFTimeInterval
+	flags   = C.FSEventStreamCreateFlags(C.kFSEventStreamCreateFlagFileEvents | C.kFSEventStreamCreateFlagNoDefer)
+	since   = uint64(C.FSEventsGetCurrentEventId())
+)
+
+var runloop C.CFRunLoopRef // global runloop which all streams are registered with
+var wg sync.WaitGroup      // used to wait until the runloop starts
+
+// source is used for synchronization purposes - it signals when runloop has
+// started and is ready via the wg. It also serves purpose of a dummy source,
+// thanks to it the runloop does not return as it also has at least one source
+// registered.
+var source = C.CFRunLoopSourceCreate(refZero, 0, &C.CFRunLoopSourceContext{
+	perform: (C.CFRunLoopPerformCallBack)(C.gosource),
+})
+
+// Errors returned when FSEvents functions fail.
+var (
+	errCreate = os.NewSyscallError("FSEventStreamCreate", errors.New("NULL"))
+	errStart  = os.NewSyscallError("FSEventStreamStart", errors.New("false"))
+)
+
+// initializes the global runloop and ensures any created stream awaits its
+// readiness.
+func init() {
+	wg.Add(1)
+	go func() {
+		// There is exactly one run loop per thread. Lock this goroutine to its
+		// thread to ensure that it's not rescheduled on a different thread while
+		// setting up the run loop.
+		runtime.LockOSThread()
+		runloop = C.CFRunLoopGetCurrent()
+		C.CFRunLoopAddSource(runloop, source, C.kCFRunLoopDefaultMode)
+		C.CFRunLoopRun()
+		panic("runloop has just unexpectedly stopped")
+	}()
+	C.CFRunLoopSourceSignal(source)
+}
+
+//export gosource
+func gosource(unsafe.Pointer) {
+	wg.Done()
+}
+
+//export gostream
+func gostream(_, info uintptr, n C.size_t, paths, flags, ids uintptr) {
+	const (
+		offchar = unsafe.Sizeof((*C.char)(nil))
+		offflag = unsafe.Sizeof(C.FSEventStreamEventFlags(0))
+		offid   = unsafe.Sizeof(C.FSEventStreamEventId(0))
+	)
+	if n == 0 {
+		return
+	}
+	ev := make([]FSEvent, 0, int(n))
+	for i := uintptr(0); i < uintptr(n); i++ {
+		switch flags := *(*uint32)(unsafe.Pointer((flags + i*offflag))); {
+		case flags&uint32(FSEventsEventIdsWrapped) != 0:
+			atomic.StoreUint64(&since, uint64(C.FSEventsGetCurrentEventId()))
+		default:
+			ev = append(ev, FSEvent{
+				Path:  C.GoString(*(**C.char)(unsafe.Pointer(paths + i*offchar))),
+				Flags: flags,
+				ID:    *(*uint64)(unsafe.Pointer(ids + i*offid)),
+			})
+		}
+
+	}
+	streamFuncs.get(info)(ev)
+}
+
+// StreamFunc is a callback called when stream receives file events.
+type streamFunc func([]FSEvent)
+
+var streamFuncs = streamFuncRegistry{m: map[uintptr]streamFunc{}}
+
+type streamFuncRegistry struct {
+	mu sync.Mutex
+	m  map[uintptr]streamFunc
+	i  uintptr
+}
+
+func (r *streamFuncRegistry) get(id uintptr) streamFunc {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return r.m[id]
+}
+
+func (r *streamFuncRegistry) add(fn streamFunc) uintptr {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.i++
+	r.m[r.i] = fn
+	return r.i
+}
+
+func (r *streamFuncRegistry) delete(id uintptr) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	delete(r.m, id)
+}
+
+// Stream represents single watch-point which listens for events scheduled by
+// the global runloop.
+type stream struct {
+	path string
+	ref  C.FSEventStreamRef
+	info uintptr
+}
+
+// NewStream creates a stream for given path, listening for file events and
+// calling fn upon receiving any.
+func newStream(path string, fn streamFunc) *stream {
+	return &stream{
+		path: path,
+		info: streamFuncs.add(fn),
+	}
+}
+
+// Start creates a FSEventStream for the given path and schedules it with
+// global runloop. It's a nop if the stream was already started.
+func (s *stream) Start() error {
+	if s.ref != nilstream {
+		return nil
+	}
+	wg.Wait()
+	p := C.CFStringCreateWithCStringNoCopy(refZero, C.CString(s.path), C.kCFStringEncodingUTF8, refZero)
+	path := C.CFArrayCreate(refZero, (*unsafe.Pointer)(unsafe.Pointer(&p)), 1, nil)
+	ctx := C.FSEventStreamContext{}
+	ref := C.EventStreamCreate(&ctx, C.uintptr_t(s.info), path, C.FSEventStreamEventId(atomic.LoadUint64(&since)), latency, flags)
+	if ref == nilstream {
+		return errCreate
+	}
+	C.FSEventStreamScheduleWithRunLoop(ref, runloop, C.kCFRunLoopDefaultMode)
+	if C.FSEventStreamStart(ref) == C.Boolean(0) {
+		C.FSEventStreamInvalidate(ref)
+		return errStart
+	}
+	C.CFRunLoopWakeUp(runloop)
+	s.ref = ref
+	return nil
+}
+
+// Stop stops underlying FSEventStream and unregisters it from global runloop.
+func (s *stream) Stop() {
+	if s.ref == nilstream {
+		return
+	}
+	wg.Wait()
+	C.FSEventStreamStop(s.ref)
+	C.FSEventStreamInvalidate(s.ref)
+	C.CFRunLoopWakeUp(runloop)
+	s.ref = nilstream
+	streamFuncs.delete(s.info)
+}