Updated liberasurecode_supported_checksum_types to accept a pointer

argument that holds the length of the list returned (i.e. the number of
supported checksum types).

3 files changed, 9 insertions, 6 deletions

diff --git a/include/erasurecode/erasurecode.h b/include/erasurecode/erasurecode.h
index 2d1e2bb..1b26b73 100644
--- a/include/erasurecode/erasurecode.h
+++ b/include/erasurecode/erasurecode.h
@@ -115,7 +115,7 @@ struct ec_args {
  * set of backends can be different from the names listed in
  * ec_backend_names above.
  *
- * @param num_backends - pointer to return number of backends in
+ * @param num_backends - pointer to int, size of list returned
  *
  * @returns list of EC backends implemented
  */
@@ -125,11 +125,11 @@ const char ** liberasurecode_supported_backends(int *num_backends);
  * Returns a list of checksum types supported for fragment data, stored in
  * individual fragment headers as part of fragment metadata
  *
- * @param num_checksum_types - pointer to return number of checksum types in
+ * @param num_checksum_types - pointer to int, size of list returned
  *
  * @returns list of checksum types supported for fragment data
  */
-const char ** liberasurecode_supported_checksum_types(void);
+const char ** liberasurecode_supported_checksum_types(int *num_checksum_types);
 
 /**
  * Create a liberasurecode instance and return a descriptor 
diff --git a/src/erasurecode.c b/src/erasurecode.c
index aedbae3..1e77896 100644
--- a/src/erasurecode.c
+++ b/src/erasurecode.c
@@ -246,12 +246,13 @@ const char ** liberasurecode_supported_backends(int *num_backends)
  * Returns a list of checksum types supported for fragment data, stored in
  * individual fragment headers as part of fragment metadata
  *
- * @param num_checksum_types - pointer to return number of checksum types in
+ * @param num_checksum_types - pointer to int, size of list returned
  *
  * @returns list of checksum types supported for fragment data
  */
-const char ** liberasurecode_supported_checksum_types(void)
+const char ** liberasurecode_supported_checksum_types(int *num_checksum_types)
 {
+    *num_checksum_types = CHKSUM_TYPES_MAX;
     return (const char **) ec_chksum_types;
 }
 
diff --git a/test/liberasurecode_test.c b/test/liberasurecode_test.c
index c0695ce..cfa24bf 100644
--- a/test/liberasurecode_test.c
+++ b/test/liberasurecode_test.c
@@ -116,9 +116,11 @@ static void test_liberasurecode_supported_backends()
 static void test_liberasurecode_supported_checksum_types()
 {
     int i;
+    int num_checksum_types;
     const char **supported_checksum_types =
-        liberasurecode_supported_checksum_types();
+        liberasurecode_supported_checksum_types(&num_checksum_types);
 
+    assert(num_checksum_types == CHKSUM_TYPES_MAX);
     for (i = 0; i < CHKSUM_TYPES_MAX; i++)
         printf("%s\n", supported_checksum_types[i]);
 }