Initial public version

components/nvs_flash/test/crc.cpp

@@ -0,0 +1,38 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// 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 <stdint.h>
+#include <stdbool.h>
+
+extern "C" unsigned long crc32_le(unsigned long crc_in, unsigned char const* data, unsigned int length)
+{
+    uint32_t i;
+    bool bit;
+    uint8_t c;
+    uint32_t crc = (uint32_t) crc_in;
+
+    while (length--) {
+        c = *data++;
+        for (i = 0x80; i > 0; i >>= 1) {
+            bit = crc & 0x80000000;
+            if (c & i) {
+                bit = !bit;
+            }
+            crc <<= 1;
+            if (bit) {
+                crc ^= 0x04c11db7;
+            }
+        }
+    }
+    return crc;
+}