add 3dim array helpers

1 files changed, 49 insertions, 4 deletions

diff --git a/crypto.c b/crypto.c
index 044db00..e7397d5 100644
--- a/crypto.c
+++ b/crypto.c
@@ -37,9 +37,8 @@ static gcry_mpi_t       ec_n;
 
 
 /**
- * brandt_crypto_init
- *
- *
+ * brandt_crypto_init initializes the crypto system and must be called before
+ * any other function from this file.
  */
 void
 brandt_crypto_init ()
@@ -297,8 +296,9 @@ smc_init2 (uint16_t size1, uint16_t size2)
 	gcry_mpi_point_t **ret;
 	gcry_mpi_point_t *data;
 
-	ret = calloc (size1, sizeof (*ret) + (size2 * sizeof (**ret)));
+	ret = calloc (size1, sizeof (*ret) + size2 * sizeof (**ret));
 	brandt_assert (NULL != ret);
+
 	data = (gcry_mpi_point_t *)&ret[size1];
 	for (i = 0; i < size1; i++)
 	{
@@ -322,6 +322,51 @@ smc_free2 (gcry_mpi_point_t **dst, uint16_t size1, uint16_t size2)
 }
 
 
+static gcry_mpi_point_t ***
+smc_init3 (uint16_t size1, uint16_t size2, uint16_t size3)
+{
+	uint16_t         i, j, k;
+	gcry_mpi_point_t ***ret;
+	gcry_mpi_point_t **layer1;
+	gcry_mpi_point_t *layer2;
+
+	ret = calloc (size1, sizeof (*ret) +
+	              size2 * sizeof (**ret) +
+	              size2 * size3 * sizeof (***ret));
+	brandt_assert (NULL != ret);
+
+	layer1 = (gcry_mpi_point_t **)&ret[size1];
+	layer2 = (gcry_mpi_point_t *)&layer1[size1*size2];
+	for (i = 0; i < size1; i++)
+	{
+		ret[i] = &layer1[i * size2];
+		for (j = 0; j < size2; j++)
+		{
+			layer1[i * size2 + j] = &layer2[(i * size2 + j) * size3];
+			for (k = 0; k < size3; k++)
+				ret[i][j][k] = gcry_mpi_point_new (0);
+		}
+	}
+	return ret;
+}
+
+
+static void
+smc_free3 (gcry_mpi_point_t ***dst,
+           uint16_t         size1,
+           uint16_t         size2,
+           uint16_t         size3)
+{
+	uint16_t i, j, k;
+
+	for (i = 0; i < size1; i++)
+		for (j = 0; j < size2; j++)
+			for (k = 0; k < size3; k++)
+				gcry_mpi_point_release (dst[i][j][k]);
+	free (dst);
+}
+
+
 /**
  * smc_sums_partial calculates sums up until the current index and stores them
  * in @a out. \f$\forall i \leq len: out_i=\sum_{h=1}^iin_h\f$