libec version is now stored in fragment header

include/erasurecode/erasurecode.h

@@ -248,6 +248,8 @@ fragment_metadata
     uint8_t     chksum_type;        /* 1 */
     uint32_t    chksum[LIBERASURECODE_MAX_CHECKSUM_LEN]; /* 32 */
     uint8_t     chksum_mismatch;    /* 1 */
+    uint8_t     backend_id;         /* 1 */
+    uint32_t    backend_version;    /* 4 */
 } fragment_metadata_t;
 
 #define FRAGSIZE_2_BLOCKSIZE(fragment_size) \

include/erasurecode/erasurecode_helpers.h

@@ -45,11 +45,12 @@
 
 typedef struct __attribute__((__packed__)) fragment_header_s
 {
-    fragment_metadata_t meta;   /* 50 bytes */
+    fragment_metadata_t meta;   /* 55 bytes */
     uint32_t            magic;  /*  4 bytes */
+    uint32_t            libec_version; /* 4 bytes */
     // We must be aligned to 16-byte boundaries
     // So, size this array accordingly
-    uint8_t             aligned_padding[10];
+    uint8_t             aligned_padding[1];
 } fragment_header_t;
 
 /* ==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~== */
@@ -137,6 +138,8 @@ int get_orig_data_size(char *buf);
 int validate_fragment(char *buf);
 int set_checksum(ec_checksum_type_t ct, char *buf, int blocksize);
 int get_checksum(char *buf);
+int set_libec_version(char *fragment);
+int get_libec_version(char *fragment, uint32_t *ver);
 
 /* ==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~== */
 

src/erasurecode_helpers.c

@@ -31,10 +31,23 @@
 #include "erasurecode_backend.h"
 #include "erasurecode_helpers.h"
 #include "erasurecode_stdinc.h"
+#include "erasurecode_version.h"
 #include "erasurecode/alg_sig.h"
 
 /* ==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~== */
 
+static bool is_valid_fragment(char *buf)
+{
+    fragment_header_t *header = (fragment_header_t *) buf;
+
+    assert(NULL != header);
+    if (header->magic == LIBERASURECODE_FRAG_HEADER_MAGIC) {
+        return true;
+    }
+
+    return false;
+}
+
 /**
  * Memory Management Methods
  * 
@@ -328,17 +341,21 @@ int get_orig_data_size(char *buf)
     return header->meta.orig_data_size;
 }
 
-/* ==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~== */
-
-int validate_fragment(char *buf)
-{
-    fragment_header_t *header = (fragment_header_t *) buf;
-
-    assert(NULL != header);
-    if (header->magic != LIBERASURECODE_FRAG_HEADER_MAGIC) {
-        return -1;
+int set_libec_version(char *buf) {
+    if (!is_valid_fragment(buf)) {
+            return -1;
     }
+    fragment_header_t *header = (fragment_header_t *) buf;
+    header->libec_version = (uint32_t)LIBERASURECODE_VERSION;
+    return 0;
+}
 
+int get_libec_version(char *buf, uint32_t *ver) {
+    if (!is_valid_fragment(buf)) {
+            return -1;
+    }
+    fragment_header_t *header = (fragment_header_t *) buf;
+    *ver = header->libec_version;
     return 0;
 }
 

src/erasurecode_postprocessing.c

@@ -34,9 +34,11 @@ void add_fragment_metadata(char *fragment,
         int idx, uint64_t orig_data_size, int blocksize,
         ec_checksum_type_t ct, int add_chksum)
 {
+    set_libec_version(fragment);
     set_fragment_idx(fragment, idx);
     set_orig_data_size(fragment, orig_data_size);
     set_fragment_payload_size(fragment, blocksize);
+    
     if (add_chksum) {
         set_checksum(ct, fragment, blocksize);
     }

test/liberasurecode_test.c

@@ -740,13 +740,17 @@ static void test_get_fragment_metadata(const ec_backend_id_t be_id, struct ec_ar
 
     for (i = 0; i < num_fragments; i++) {
         char * data = NULL;
+        uint32_t ver = 0;
+        char *header = NULL;
         memset(&cur_frag, -1, sizeof(fragment_metadata_t));
         if (i < args->k) {
             rc = liberasurecode_get_fragment_metadata(encoded_data[i], &cur_frag);
             data = get_data_ptr_from_fragment(encoded_data[i]);
+            header = encoded_data[i];
         } else {
             rc = liberasurecode_get_fragment_metadata(encoded_parity[i - args->k], &cur_frag);
             data = get_data_ptr_from_fragment(encoded_parity[i - args->k]);
+            header = encoded_parity[i - args->k];
         }
         assert(rc == 0);
         assert(cur_frag.orig_data_size == orig_data_size);
@@ -755,6 +759,9 @@ static void test_get_fragment_metadata(const ec_backend_id_t be_id, struct ec_ar
         validate_fragment_checksum(args, &cur_frag, data);
         rc = memcmp(&cur_frag, &cmp_frag, sizeof(fragment_metadata_t));
         assert(rc != 0);
+        rc = get_libec_version(header, &ver);
+        assert(rc == 0);
+        assert(ver == LIBERASURECODE_VERSION);
     }
 }