1 files changed, 153 insertions, 0 deletions
diff --git a/ext/librethinkdbxx/src/utils.cc b/ext/librethinkdbxx/src/utils.cc
new file mode 100644
index 00000000..5a2c244d
--- /dev/null
+++ b/ext/librethinkdbxx/src/utils.cc
@@ -0,0 +1,153 @@
+#include "utils.h"
+#include "error.h"
+
+namespace RethinkDB {
+
+size_t utf8_encode(unsigned int code, char* buf) {
+    if (!(code & ~0x7F)) {
+        buf[0] = code;
+        return 1;
+    } else if (!(code & ~0x7FF)) {
+        buf[0] = 0xC0 | (code >> 6);
+        buf[1] = 0x80 | (code & 0x3F);
+        return 2;
+    } else if (!(code & ~0xFFFF)) {
+        buf[0] = 0xE0 | (code >> 12);
+        buf[1] = 0x80 | ((code >> 6) & 0x3F);
+        buf[2] = 0x80 | (code & 0x3F);
+        return 3;
+    } else if (!(code & ~0x1FFFFF)) {
+        buf[0] = 0xF0 | (code >> 18);
+        buf[1] = 0x80 | ((code >> 12) & 0x3F);
+        buf[2] = 0x80 | ((code >> 6) & 0x3F);
+        buf[3] = 0x80 | (code & 0x3F);
+        return 4;
+    } else if (!(code & ~0x3FFFFFF)) {
+        buf[0] = 0xF8 | (code >> 24);
+        buf[1] = 0x80 | ((code >> 18) & 0x3F);
+        buf[2] = 0x80 | ((code >> 12) & 0x3F);
+        buf[3] = 0x80 | ((code >> 6) & 0x3F);
+        buf[4] = 0x80 | (code & 0x3F);
+        return 5;
+    } else if (!(code & ~0x7FFFFFFF)) {
+        buf[0] = 0xFC | (code >> 30);
+        buf[1] = 0x80 | ((code >> 24) & 0x3F);
+        buf[2] = 0x80 | ((code >> 18) & 0x3F);
+        buf[3] = 0x80 | ((code >> 12) & 0x3F);
+        buf[4] = 0x80 | ((code >> 6) & 0x3F);
+        buf[5] = 0x80 | (code & 0x3F);
+        return 6;
+    } else {
+        throw Error("Invalid unicode codepoint %ud", code);
+    }
+}
+
+bool base64_decode(char c, int* out) {
+    if (c >= 'A' && c <= 'Z') {
+        *out = c - 'A';
+    } else if (c >= 'a' && c <= 'z') {
+        *out = c - ('a' - 26);
+    } else if (c >= '0' && c <= '9') {
+        *out = c - ('0' - 52);
+    } else if (c == '+') {
+        *out = 62;
+    } else if (c == '/') {
+        *out = 63;
+    } else {
+        return false;
+    }
+    return true;
+}
+
+bool base64_decode(const std::string& in, std::string& out) {
+    out.clear();
+    out.reserve(in.size() * 3 / 4);
+    auto read = in.begin();
+    while (true) {
+        int c[4];
+        int end = 4;
+        for (int i = 0; i < 4; i++) {
+            while (true) {
+                if (read == in.end()) {
+                    c[i] = 0;
+                    end = i;
+                    i = 3;
+                    break;
+                } else if (base64_decode(*read, &c[i])) {
+                    ++read;
+                    break;
+                } else {
+                    ++read;
+                }
+            }
+        }
+        if (end == 1) return false;
+        int val = c[0] << 18 | c[1] << 12 | c[2] << 6 | c[3];
+        if (end > 1) out.append(1, val >> 16);
+        if (end > 2) out.append(1, val >> 8 & 0xFF);
+        if (end > 3) out.append(1, val & 0xFF);
+        if (end != 4) break;
+    }
+    return true;
+}
+
+char base64_encode(unsigned int c) {
+    if (c < 26) {
+        return 'A' + c;
+    } else if (c < 52) {
+        return 'a' + c - 26;
+    } else if (c < 62) {
+        return '0' + c - 52;
+    } else if (c == 62) {
+        return '+';
+    } else if (c == 63) {
+        return '/';
+    } else {
+        throw Error("unreachable: base64 encoding %d", c);
+    }
+}
+
+void base64_encode(unsigned int* c, int n, std::string& out) {
+    if (n == 0) {
+        return;
+    }
+    out.append(1, base64_encode(c[0] >> 2));
+    out.append(1, base64_encode((c[0] & 0x3) << 4 | c[1] >> 4));
+    if (n == 1) {
+        out.append("==");
+        return;
+    }
+    out.append(1, base64_encode((c[1] & 0xF) << 2 | c[2] >> 6));
+    if (n == 2) {
+        out.append("=");
+        return;
+    }
+    out.append(1, base64_encode(c[2] & 0x3F));
+}
+
+std::string base64_encode(const std::string& in) {
+    std::string out;
+    out.reserve(in.size() * 4 / 3 + in.size() / 48 + 3);
+    auto read = in.begin();
+    while (true) {
+        for (int group = 0; group < 16; ++group) {
+            unsigned int c[3];
+            int i = 0;
+            for (; i < 3; ++i) {
+                if (read == in.end()) {
+                    c[i] = 0;
+                    break;
+                } else {
+                    c[i] = static_cast<unsigned char>(*read++);
+                }
+            }
+            base64_encode(c, i, out);
+            if (i != 3) {
+                return out;
+            }
+        }
+        out.append("\n");
+    }
+}
+
+}