Check if dir ls/dump returns nil

Change-Id: I9a0a74f53825fc0255bc664c06e32eaef6c45d82
Signed-off-by: Ondrej Fabry <ofabry@cisco.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/adapter/vppapiclient/stat_client.go b/adapter/vppapiclient/stat_client.go
index 55705bd..24700a3 100644
--- a/adapter/vppapiclient/stat_client.go
+++ b/adapter/vppapiclient/stat_client.go
@@ -161,6 +161,7 @@ govpp_stat_segment_string_vector(uint8_t ** string_vector, char *string)
 */
 import "C"
 import (
+	"errors"
 	"fmt"
 	"os"
 	"unsafe"
@@ -169,6 +170,11 @@ import (
 )
 
 var (
+	ErrStatDirBusy  = errors.New("stat dir busy")
+	ErrStatDumpBusy = errors.New("stat dump busy")
+)
+
+var (
 	// DefaultStatSocket is the default path for the VPP stat socket file.
 	DefaultStatSocket = "/run/vpp/stats.sock"
 )
@@ -219,6 +225,9 @@ func (c *statClient) Disconnect() error {
 
 func (c *statClient) ListStats(patterns ...string) (stats []string, err error) {
 	dir := C.govpp_stat_segment_ls(convertStringSlice(patterns))
+	if dir == nil {
+		return nil, ErrStatDirBusy
+	}
 	defer C.govpp_stat_segment_vec_free(unsafe.Pointer(dir))
 
 	l := C.govpp_stat_segment_vec_len(unsafe.Pointer(dir))
@@ -233,9 +242,15 @@ func (c *statClient) ListStats(patterns ...string) (stats []string, err error) {
 
 func (c *statClient) DumpStats(patterns ...string) (stats []*adapter.StatEntry, err error) {
 	dir := C.govpp_stat_segment_ls(convertStringSlice(patterns))
+	if dir == nil {
+		return nil, ErrStatDirBusy
+	}
 	defer C.govpp_stat_segment_vec_free(unsafe.Pointer(dir))
 
 	dump := C.govpp_stat_segment_dump(dir)
+	if dump == nil {
+		return nil, ErrStatDumpBusy
+	}
 	defer C.govpp_stat_segment_data_free(dump)
 
 	l := C.govpp_stat_segment_vec_len(unsafe.Pointer(dump))