API: Use string type instead of u8.

The new string type is modelled after string in proto3.
It is always variable length.

Change-Id: I64884067e28a80072c8dac31b7c7c82d6e306051
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Michal Cmarada <mcmarada@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>

3 files changed, 56 insertions, 0 deletions

diff --git a/src/vlibapi/CMakeLists.txt b/src/vlibapi/CMakeLists.txt
index 55f87b8f7ac..dfd6b5b5045 100644
--- a/src/vlibapi/CMakeLists.txt
+++ b/src/vlibapi/CMakeLists.txt
@@ -17,6 +17,7 @@ install(
   api.h
   vat_helper_macros.h
   api_common.h
+  api_types.h
 
   DESTINATION
   include/vlibapi
diff --git a/src/vlibapi/api_common.h b/src/vlibapi/api_common.h
index 497a1e8bd16..735921b30f7 100644
--- a/src/vlibapi/api_common.h
+++ b/src/vlibapi/api_common.h
@@ -25,6 +25,7 @@
  */
 
 #include <vppinfra/clib_error.h>
+#include <vlibapi/api_types.h>
 #include <svm/svm_common.h>
 #include <svm/queue.h>
 
diff --git a/src/vlibapi/api_types.h b/src/vlibapi/api_types.h
new file mode 100644
index 00000000000..759298e735d
--- /dev/null
+++ b/src/vlibapi/api_types.h
@@ -0,0 +1,54 @@
+/*
+ *------------------------------------------------------------------
+ * api_types.h
+ *
+ * Copyright (c) 2018 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *------------------------------------------------------------------
+ */
+
+#ifndef included_api_types_h
+#define included_api_types_h
+
+#include <vppinfra/types.h>
+
+/* VPP API string type */
+typedef struct
+{
+  u32 length;
+  u8 buf[0];
+} __attribute__ ((packed)) vl_api_string_t;
+
+static inline int
+vl_api_to_api_string (u32 len, const char *buf, vl_api_string_t * str)
+{
+  if (strncpy_s ((char *) str->buf, len, buf, len - 1) != 0)
+    len = 0;
+  str->length = clib_host_to_net_u32 (len);
+  return len + sizeof (u32);
+}
+
+/* Return a C string from API string */
+static inline u8 *
+vl_api_from_api_string (vl_api_string_t * astr)
+{
+  return astr->buf;
+}
+
+static inline u32
+vl_api_string_len (vl_api_string_t * astr)
+{
+  return clib_net_to_host_u32 (astr->length);
+}
+
+#endif