adds vendor directory

vendors dependencies in standard `vendor` directory, managed by glide

vendor/github.com/mattn/go-pointer/README.md

@@ -0,0 +1,29 @@
+# go-pointer
+
+Utility for cgo
+
+## Usage
+
+https://github.com/golang/proposal/blob/master/design/12416-cgo-pointers.md
+
+In go 1.6, cgo argument can't be passed Go pointer.
+
+```
+var s string
+C.pass_pointer(pointer.Save(&s))
+v := *(pointer.Restore(C.get_from_pointer()).(*string))
+```
+
+## Installation
+
+```
+go get github.com/mattn/go-pointer
+```
+
+## License
+
+MIT
+
+## Author
+
+Yasuhiro Matsumoto (a.k.a mattn)

vendor/github.com/mattn/go-pointer/_example/callback.h

@@ -0,0 +1,9 @@
+#include <unistd.h>
+
+typedef void (*callback)(void*);
+
+static void call_later(int delay, callback cb, void* data) {
+  sleep(delay);
+  cb(data);
+}
+

vendor/github.com/mattn/go-pointer/_example/main.go

@@ -0,0 +1,29 @@
+package main
+
+/*
+#include "callback.h"
+
+void call_later_go_cb(void*);
+*/
+import "C"
+import (
+	"fmt"
+	"unsafe"
+
+	"github.com/mattn/go-pointer"
+)
+
+type Foo struct {
+	v int
+}
+
+func main() {
+	f := &Foo{123}
+	C.call_later(3, C.callback(C.call_later_go_cb), pointer.Save(f))
+}
+
+//export call_later_go_cb
+func call_later_go_cb(data unsafe.Pointer) {
+	f := pointer.Restore(data).(*Foo)
+	fmt.Println(f.v)
+}

vendor/github.com/mattn/go-pointer/example/example.go

@@ -0,0 +1,13 @@
+package example
+
+/*
+void *pass_pointer(void* p) {
+  return p;
+}
+*/
+import "C"
+import "unsafe"
+
+func PassPointer(ptr unsafe.Pointer) unsafe.Pointer {
+	return C.pass_pointer(ptr)
+}

vendor/github.com/mattn/go-pointer/pointer.go

@@ -0,0 +1,59 @@
+package pointer
+
+// #include <stdlib.h>
+import "C"
+import (
+	"sync"
+	"unsafe"
+)
+
+var (
+	mutex sync.Mutex
+	store = map[unsafe.Pointer]interface{}{}
+)
+
+func Save(v interface{}) unsafe.Pointer {
+	if v == nil {
+		return nil
+	}
+
+	// Generate real fake C pointer.
+	// This pointer will not store any data, but will bi used for indexing purposes.
+	// Since Go doest allow to cast dangling pointer to unsafe.Pointer, we do rally allocate one byte.
+	// Why we need indexing, because Go doest allow C code to store pointers to Go data.
+	var ptr unsafe.Pointer = C.malloc(C.size_t(1))
+	if ptr == nil {
+		panic("can't allocate 'cgo-pointer hack index pointer': ptr == nil")
+	}
+
+	mutex.Lock()
+	store[ptr] = v
+	mutex.Unlock()
+
+	return ptr
+}
+
+func Restore(ptr unsafe.Pointer) interface{} {
+	if ptr == nil {
+		return nil
+	}
+
+	mutex.Lock()
+	defer mutex.Unlock()
+	if v, ok := store[ptr]; ok {
+		return v
+	}
+	return nil
+}
+
+func Unref(ptr unsafe.Pointer) {
+	if ptr == nil {
+		return
+	}
+
+	mutex.Lock()
+	delete(store, ptr)
+	mutex.Unlock()
+
+	C.free(ptr)
+}