o add bsnes

bsnes/lib/nall/base64.hpp

@@ -0,0 +1,92 @@
+#ifndef NALL_BASE64_HPP
+#define NALL_BASE64_HPP
+
+#include <string.h>
+
+#include <nall/new.hpp>
+#include <nall/stdint.hpp>
+
+namespace nall {
+  class base64 {
+  public:
+    static bool encode(char *&output, const uint8_t* input, unsigned inlength) {
+      output = new(zeromemory) char[inlength * 8 / 6 + 6];
+
+      unsigned i = 0, o = 0;
+      while(i < inlength) {
+        switch(i % 3) {
+          case 0: {
+            output[o++] = enc(input[i] >> 2);
+            output[o] = enc((input[i] & 3) << 4);
+          } break;
+
+          case 1: {
+            uint8_t prev = dec(output[o]);
+            output[o++] = enc(prev + (input[i] >> 4));
+            output[o] = enc((input[i] & 15) << 2);
+          } break;
+
+          case 2: {
+            uint8_t prev = dec(output[o]);
+            output[o++] = enc(prev + (input[i] >> 6));
+            output[o++] = enc(input[i] & 63);
+          } break;
+        }
+
+        i++;
+      }
+
+      return true;
+    }
+
+    static bool decode(uint8_t *&output, unsigned &outlength, const char *input) {
+      unsigned inlength = strlen(input), infix = 0;
+      output = new(zeromemory) uint8_t[inlength];
+
+      unsigned i = 0, o = 0;
+      while(i < inlength) {
+        uint8_t x = dec(input[i]);
+
+        switch(i++ & 3) {
+          case 0: {
+            output[o] = x << 2;
+          } break;
+
+          case 1: {
+            output[o++] |= x >> 4;
+            output[o] = (x & 15) << 4;
+          } break;
+
+          case 2: {
+            output[o++] |= x >> 2;
+            output[o] = (x & 3) << 6;
+          } break;
+
+          case 3: {
+            output[o++] |= x;
+          } break;
+        }
+      }
+
+      outlength = o;
+      return true;
+    }
+
+  private:
+    static char enc(uint8_t n) {
+      static char lookup_table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
+      return lookup_table[n & 63];
+    }
+
+    static uint8_t dec(char n) {
+      if(n >= 'A' && n <= 'Z') return n - 'A';
+      if(n >= 'a' && n <= 'z') return n - 'a' + 26;
+      if(n >= '0' && n <= '9') return n - '0' + 52;
+      if(n == '-') return 62;
+      if(n == '_') return 63;
+      return 0;
+    }
+  };
+}
+
+#endif