Add erasure package in its full form v1.0

pkg/storage/erasure/ec-encode.c

@@ -0,0 +1,71 @@
+/*
+ * Mini Object Storage, (C) 2014 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "ec-code.h"
+#include "ec-common.h"
+
+int32_t minio_init_encoder (int technique, int k, int m,
+                            uint8_t **encode_matrix,
+                            uint8_t **encode_tbls)
+{
+        size_t encode_matrix_size;
+        size_t encode_tbls_size;
+        uint8_t *tmp_matrix;
+        uint8_t *tmp_tbls;
+
+        tmp_matrix = (uint8_t *) malloc (k * (k + m));
+        tmp_tbls = (uint8_t *) malloc (k * (k + m) * 32);
+
+	if (technique == 0) {
+                /*
+                  Commonly used method for choosing coefficients in erasure
+                  encoding but does not guarantee invertable for every sub
+                  matrix.  For large k it is possible to find cases where the
+                  decode matrix chosen from sources and parity not in erasure
+                  are not invertable. Users may want to adjust for k > 5.
+                  -- Intel
+                */
+		gf_gen_rs_matrix (tmp_matrix, k + m, k);
+	} else if (technique == 1) {
+		gf_gen_cauchy1_matrix (tmp_matrix, k + m, k);
+        }
+
+	ec_init_tables(k, m, &tmp_matrix[k * k], tmp_tbls);
+
+        *encode_matrix = tmp_matrix;
+        *encode_tbls = tmp_tbls;
+
+        return 0;
+}
+
+uint32_t minio_calc_chunk_size (int k, uint32_t split_len)
+{
+        int alignment;
+        int remainder;
+        int padded_len;
+
+        alignment = k * SIMD_ALIGN;
+        remainder = split_len % alignment;
+
+        padded_len = split_len;
+        if (remainder) {
+                padded_len = split_len + (alignment - remainder);
+        }
+        return padded_len / k;
+}