Decommision src_common prior to reintroducing it for files common between eth and plugins

src/uint256.h

@@ -0,0 +1,61 @@
+/*******************************************************************************
+ *   Ledger Ethereum App
+ *   (c) 2016-2019 Ledger
+ *
+ *  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.
+ ********************************************************************************/
+
+// Adapted from https://github.com/calccrypto/uint256_t
+
+#ifndef _UINT256_H_
+#define _UINT256_H_
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "uint128.h"
+
+typedef struct uint256_t {
+    uint128_t elements[2];
+} uint256_t;
+
+void readu256BE(const uint8_t *const buffer, uint256_t *const target);
+bool zero256(const uint256_t *const number);
+void copy256(uint256_t *const target, const uint256_t *const number);
+void clear256(uint256_t *const target);
+void shiftl256(const uint256_t *const number, uint32_t value, uint256_t *const target);
+void shiftr256(const uint256_t *const number, uint32_t value, uint256_t *const target);
+uint32_t bits256(const uint256_t *const number);
+bool equal256(const uint256_t *const number1, const uint256_t *const number2);
+bool gt256(const uint256_t *const number1, const uint256_t *const number2);
+bool gte256(const uint256_t *const number1, const uint256_t *const number2);
+void add256(const uint256_t *const number1,
+            const uint256_t *const number2,
+            uint256_t *const target);
+void sub256(const uint256_t *const number1,
+            const uint256_t *const number2,
+            uint256_t *const target);
+void or256(const uint256_t *const number1, const uint256_t *const number2, uint256_t *const target);
+void mul256(const uint256_t *const number1,
+            const uint256_t *const number2,
+            uint256_t *const target);
+void divmod256(const uint256_t *const l,
+               const uint256_t *const r,
+               uint256_t *const div,
+               uint256_t *const mod);
+bool tostring256(const uint256_t *const number, uint32_t base, char *const out, uint32_t outLength);
+bool tostring256_signed(const uint256_t *const number,
+                        uint32_t base,
+                        char *const out,
+                        uint32_t out_length);
+
+#endif  // _UINT256_H_