2 files changed, 39 insertions, 36 deletions

diff --git a/adapter/vppapiclient/empty_adapter.go b/adapter/vppapiclient/empty_adapter.go
index c3010a0..7514048 100644
--- a/adapter/vppapiclient/empty_adapter.go
+++ b/adapter/vppapiclient/empty_adapter.go
@@ -32,7 +32,7 @@ func NewVppAdapter(string) adapter.VppAdapter {
 }
 
 func (a *vppAPIClientAdapter) Connect() error {
-	return nil
+	return adapter.ErrNotImplemented
 }
 
 func (a *vppAPIClientAdapter) Disconnect() {
@@ -47,7 +47,7 @@ func (a *vppAPIClientAdapter) SendMsg(clientID uint32, data []byte) error {
 	return nil
 }
 
-func (a *vppAPIClientAdapter) SetMsgCallback(cb func(context uint32, msgID uint16, data []byte)) {
+func (a *vppAPIClientAdapter) SetMsgCallback(cb adapter.MsgCallback) {
 	// no op
 }
 
diff --git a/adapter/vppapiclient/vppapiclient_adapter.go b/adapter/vppapiclient/vppapiclient_adapter.go
index c77d7f1..7aafa55 100644
--- a/adapter/vppapiclient/vppapiclient_adapter.go
+++ b/adapter/vppapiclient/vppapiclient_adapter.go
@@ -28,7 +28,7 @@ package vppapiclient
 #include <arpa/inet.h>
 #include <vpp-api/client/vppapiclient.h>
 
-extern void go_msg_callback(uint16_t, uint32_t, void*, size_t);
+extern void go_msg_callback(uint16_t msg_id, uint32_t context, void* data, size_t size);
 
 typedef struct __attribute__((__packed__)) _req_header {
     uint16_t msg_id;
@@ -38,7 +38,7 @@ typedef struct __attribute__((__packed__)) _req_header {
 
 typedef struct __attribute__((__packed__)) _reply_header {
     uint16_t msg_id;
-    uint32_t context;
+    uint32_t context; // currently not all reply messages contain context field
 } reply_header_t;
 
 static void
@@ -49,23 +49,23 @@ govpp_msg_callback (unsigned char *data, int size)
 }
 
 static int
-govpp_connect (char *shm)
+govpp_send(uint32_t context, void *data, size_t size)
 {
-    return vac_connect("govpp", shm, govpp_msg_callback, 32);
+	req_header_t *header = ((req_header_t *)data);
+	header->context = htonl(context);
+    return vac_write(data, size);
 }
 
 static int
-govvp_disconnect()
+govpp_connect (char *shm)
 {
-    return vac_disconnect();
+    return vac_connect("govpp", shm, govpp_msg_callback, 32);
 }
 
 static int
-govpp_send(uint32_t context, void *data, size_t size)
+govvp_disconnect()
 {
-	req_header_t *header = ((req_header_t *)data);
-	header->context = htonl(context);
-    return vac_write(data, size);
+    return vac_disconnect();
 }
 
 static uint32_t
@@ -79,6 +79,7 @@ import "C"
 import (
 	"fmt"
 	"os"
+	"path/filepath"
 	"reflect"
 	"unsafe"
 
@@ -98,7 +99,7 @@ const (
 // vppAPIClientAdapter is the opaque context of the adapter.
 type vppAPIClientAdapter struct {
 	shmPrefix string
-	callback  func(context uint32, msgId uint16, data []byte)
+	callback  adapter.MsgCallback
 }
 
 var vppClient *vppAPIClientAdapter // global vpp API client adapter context
@@ -138,6 +139,7 @@ func (a *vppAPIClientAdapter) GetMsgID(msgName string, msgCrc string) (uint16, e
 
 	msgID := uint16(C.govpp_get_msg_index(nameAndCrc))
 	if msgID == ^uint16(0) {
+		// VPP does not know this message
 		return msgID, fmt.Errorf("unknown message: %v (crc: %v)", msgName, msgCrc)
 	}
 
@@ -154,40 +156,41 @@ func (a *vppAPIClientAdapter) SendMsg(context uint32, data []byte) error {
 }
 
 // SetMsgCallback sets a callback function that will be called by the adapter whenever a message comes from VPP.
-func (a *vppAPIClientAdapter) SetMsgCallback(cb func(context uint32, msgID uint16, data []byte)) {
+func (a *vppAPIClientAdapter) SetMsgCallback(cb adapter.MsgCallback) {
 	a.callback = cb
 }
 
 // WaitReady blocks until shared memory for sending
 // binary api calls is present on the file system.
 func (a *vppAPIClientAdapter) WaitReady() error {
-	watcher, err := fsnotify.NewWatcher()
-	if err != nil {
-		return err
-	}
-	defer watcher.Close()
-
-	err = watcher.Add(watchedFolder)
-	if err != nil {
-		return err
-	}
-	// Path to the shared memory segment with prefix, if set
+	// Path to the shared memory segment
 	var path string
 	if a.shmPrefix == "" {
-		path = watchedFolder + watchedFile
+		path = filepath.Join(watchedFolder, watchedFile)
 	} else {
-		path = watchedFolder + a.shmPrefix + "-" + watchedFile
-	}
-	if fileExists(path) {
-		return nil
+		path = filepath.Join(watchedFolder, a.shmPrefix+"-"+watchedFile)
 	}
 
-	for {
-		ev := <-watcher.Events
-		if ev.Name == path && (ev.Op&fsnotify.Create) == fsnotify.Create {
-			break
+	// Watch folder if file does not exist yet
+	if !fileExists(path) {
+		watcher, err := fsnotify.NewWatcher()
+		if err != nil {
+			return err
+		}
+		defer watcher.Close()
+
+		if err := watcher.Add(watchedFolder); err != nil {
+			return err
+		}
+
+		for {
+			ev := <-watcher.Events
+			if ev.Name == path && (ev.Op&fsnotify.Create) == fsnotify.Create {
+				break
+			}
 		}
 	}
+
 	return nil
 }
 
@@ -206,5 +209,5 @@ func go_msg_callback(msgID C.uint16_t, context C.uint32_t, data unsafe.Pointer,
 	slice := &reflect.SliceHeader{Data: uintptr(data), Len: int(size), Cap: int(size)}
 	byteArr := *(*[]byte)(unsafe.Pointer(slice))
 
-	vppClient.callback(uint32(context), uint16(msgID), byteArr)
-}
\ No newline at end of file
+	vppClient.callback(uint16(msgID), uint32(context), byteArr)
+}