Move backend metadata adding to fragment allocation

On the first consideration[1], metadata_adder is defined as a extra byte
size for "each" fragment. However, current implementation is an element
affects to data_len. (i.e. aligned_data_size for original segment data)

We should make metadata_adder to be a fixed value against to each fragment,
otherwise the extra bytes for the fragments will have flexible length depends
on "K". It will be quite complex for backend implementation to know "How large
bytes the raw data size is", "How large bytes the backend could use as extra
bytes for each fragment".

1: https://bitbucket.org/tsg-/liberasurecode/commits/032b57d9b1c7aadc547fccbacf88af786c9067e7?at=master

1 files changed, 11 insertions, 6 deletions

diff --git a/src/erasurecode_preprocessing.c b/src/erasurecode_preprocessing.c
index b55f635..7723569 100644
--- a/src/erasurecode_preprocessing.c
+++ b/src/erasurecode_preprocessing.c
@@ -49,7 +49,7 @@ int prepare_fragments_for_encode(ec_backend_t instance,
 
     for (i = 0; i < k; i++) {
         int payload_size = data_len > bsize ? bsize : data_len;
-        char *fragment = (char *) alloc_fragment_buffer(bsize);
+        char *fragment = (char *) alloc_fragment_buffer(instance, bsize);
         if (NULL == fragment) {
             ret = -ENOMEM;
             goto out_error;
@@ -67,7 +67,7 @@ int prepare_fragments_for_encode(ec_backend_t instance,
     }
 
     for (i = 0; i < m; i++) {
-        char *fragment = (char *) alloc_fragment_buffer(bsize);
+        char *fragment = (char *) alloc_fragment_buffer(instance, bsize);
         if (NULL == fragment) {
             ret = -ENOMEM;
             goto out_error;
@@ -108,6 +108,7 @@ out_error:
  * so in the failure case.
  */
 int prepare_fragments_for_decode(
+        ec_backend_t instance,
         int k, int m,
         char **data, char **parity,
         int  *missing_idxs,
@@ -135,14 +136,16 @@ int prepare_fragments_for_decode(
          * 'data_list'
          */
         if (NULL == data[i]) {
-            data[i] = alloc_fragment_buffer(fragment_size - sizeof(fragment_header_t));
+            data[i] = alloc_fragment_buffer(
+                instance, fragment_size - sizeof(fragment_header_t));
             if (NULL == data[i]) {
                 log_error("Could not allocate data buffer!");
                 return -1;
             }
             *realloc_bm = *realloc_bm | (1 << i);
         } else if (!is_addr_aligned((unsigned long)data[i], 16)) {
-            char *tmp_buf = alloc_fragment_buffer(fragment_size - sizeof(fragment_header_t));
+            char *tmp_buf = alloc_fragment_buffer(
+                instance, fragment_size - sizeof(fragment_header_t));
             if (NULL == tmp_buf) {
                 log_error("Could not allocate temp buffer!");
                 return -1;
@@ -174,14 +177,16 @@ int prepare_fragments_for_decode(
          * DO NOT FREE: the python GC should free the original when cleaning up 'data_list'
          */
         if (NULL == parity[i]) {
-            parity[i] = alloc_fragment_buffer(fragment_size-sizeof(fragment_header_t));
+            parity[i] = alloc_fragment_buffer(
+                instance, fragment_size-sizeof(fragment_header_t));
             if (NULL == parity[i]) {
                 log_error("Could not allocate parity buffer!");
                 return -1;
             }
             *realloc_bm = *realloc_bm | (1 << (k + i));
         } else if (!is_addr_aligned((unsigned long)parity[i], 16)) {
-            char *tmp_buf = alloc_fragment_buffer(fragment_size-sizeof(fragment_header_t));
+            char *tmp_buf = alloc_fragment_buffer(
+                instance, fragment_size-sizeof(fragment_header_t));
             if (NULL == tmp_buf) {
                 log_error("Could not allocate temp buffer!");
                 return -1;