Initial Commit

src/base58.cpp

@@ -0,0 +1,113 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2009-2019 The Bitcoin Core developers
+ * Copyright (c) 2009-2019 Bitcoin Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * Based on code from https://github.com/bitcoin/bitcoin/blob/f1e2f2a85962c1664e4e55471061af0eaa798d40/src/base58.cpp
+ */
+#include <algorithm>
+#include <cstddef>
+#include <cassert>
+#include <libeosio/base58.h>
+
+namespace libeosio {
+
+static const char charmap[59] = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
+
+std::string base58_encode(const unsigned char* pbegin, const unsigned char* pend) {
+
+    // Skip & count leading zeroes.
+    int zeroes = 0;
+    int length = 0;
+    while (pbegin != pend && *pbegin == 0) {
+        pbegin++;
+        zeroes++;
+    }
+    // Allocate enough space in big-endian base58 representation.
+    std::size_t size = (pend - pbegin) * 138 / 100 + 1; // log(256) / log(58), rounded up.
+    std::vector<unsigned char> b58(size);
+    // Process the bytes.
+    while (pbegin != pend) {
+        int carry = *pbegin;
+        int i = 0;
+        // Apply "b58 = b58 * 256 + ch".
+        for (std::vector<unsigned char>::reverse_iterator it = b58.rbegin(); (carry != 0 || i < length) && (it != b58.rend()); it++, i++) {
+            carry += 256 * (*it);
+            *it = static_cast<unsigned char>(carry % 58);
+            carry /= 58;
+        }
+
+        assert(carry == 0);
+        length = i;
+        pbegin++;
+    }
+    // Skip leading zeroes in base58 result.
+    std::vector<unsigned char>::iterator it = b58.begin() + (size - length);
+    while (it != b58.end() && *it == 0)
+        it++;
+    // Translate the result into a string.
+    std::string str;
+    str.reserve(zeroes + (b58.end() - it));
+    str.assign(zeroes, '1');
+    while (it != b58.end())
+        str += charmap[*(it++)];
+    return str;
+}
+
+std::string base58_encode(const std::string& str) {
+
+    const unsigned char *ptr = (const unsigned char *) str.c_str();
+    return base58_encode(ptr, ptr + str.length());
+}
+
+std::string base58_encode(const std::vector<unsigned char>& vch) {
+
+    return base58_encode(vch.data(), vch.data() + vch.size());
+}
+
+bool is_base58(char ch) {
+	for(unsigned int i=0; i < sizeof(charmap); i++) {
+		if (ch == charmap[i]) {
+			return true;
+		}
+	}
+	return false;
+}
+
+size_t is_base58(const std::string& str) {
+
+	auto p = std::find_if_not(str.begin(), str.end(), static_cast<bool (*)(char)>(is_base58));
+
+	if (p == str.end()) {
+		return std::string::npos;
+	}
+	return p - str.begin();
+}
+
+std::string& base58_strip(std::string &str) {
+	str.erase(std::remove_if(str.begin(), str.end(), [] (std::string::value_type ch)
+		{ return is_base58(ch) == false; }
+	), str.end());
+    return str;
+}
+
+} // namespace libeosio