Enable to get fragment_len includes metadata_adder

This patch allows to get correct fragment size includes metadata_adder.

Current implementaion automatically allocates extra bytes for the metadata_adder
in alloc_buffer, and then, no information about the extra bytes will be returned
to the api caller side. It's too confusable because callers couldn't know how size they
assumes as the fragment size.

To be easy to find out the size infomation, this patch adds "frag_adder_size"
variable into fragment metadata and also some functions to get fragment size.

The definitions of these size infomation are here,

fragment_meta:
- size-> raw data size used to encode/fragment_to_string
- frag_adder_size-> metadata_adder of backend specification

And the definitions of functions are here,

- get_fragment_size:
  -> return sizeof(fragument_header) + size + frag_adder_size

- get_fragment_buffer_size:
  -> return size + frag_adder_size

- get_fragment_payload_size:
  -> return size

By using these function above, users could get the size information
directly from fragments. It results in enabling to return fragment_len
to the caller side easily.

1 files changed, 4 insertions, 1 deletions

diff --git a/test/liberasurecode_test.c b/test/liberasurecode_test.c
index 04d06cf..3d9ef6c 100644
--- a/test/liberasurecode_test.c
+++ b/test/liberasurecode_test.c
@@ -592,8 +592,11 @@ static void encode_decode_test_impl(const ec_backend_id_t be_id,
     int num_avail_frags = 0;
     char *orig_data_ptr = NULL;
     int remaining = 0;
+    ec_backend_t be = NULL;
 
     desc = liberasurecode_instance_create(be_id, args);
+    be = liberasurecode_backend_instance_get_by_desc(desc);
+
     if (-EBACKENDNOTAVAIL == desc) {
         fprintf (stderr, "Backend library not available!\n");
         return;
@@ -614,7 +617,7 @@ static void encode_decode_test_impl(const ec_backend_id_t be_id,
         assert(header != NULL);
         fragment_metadata_t metadata = header->meta;
         assert(metadata.idx == i);
-        assert(metadata.size == encoded_fragment_len - frag_header_size);
+        assert(metadata.size == encoded_fragment_len - frag_header_size - be->common.metadata_adder);
         assert(metadata.orig_data_size == orig_data_size);
         char *data_ptr = frag + frag_header_size;
         int cmp_size = remaining >= metadata.size ? metadata.size : remaining;