#define  UNDEFINE_BASE64_DECODECHAR  (0xFF)
#define  _BAD  UNDEFINE_BASE64_DECODECHAR

const unsigned char Base64_EncodeTable[] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

const unsigned char Base64_DecodeTable[128] = {
 _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD,
 _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD,
 _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD,
 _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD,
 _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD, _BAD,
 _BAD, _BAD, _BAD, 0x3E, _BAD, _BAD, _BAD, 0x3F,
 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B,
 0x3C, 0x3D, _BAD, _BAD, _BAD, 0x00, _BAD, _BAD,
 _BAD, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E,
 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16,
 0x17, 0x18, 0x19, _BAD, _BAD, _BAD, _BAD, _BAD,
 _BAD, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20,
 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30,
 0x31, 0x32, 0x33, _BAD, _BAD, _BAD, _BAD, _BAD
};

int Base64_Encode(unsigned char* pSStr, unsigned char* pDStr)
{
   int len = (int)strlen(reinterpret_cast<const char*>(pSStr));
   int equ_num = len%3;
   int i = 0;
   int dStrLen = 0;
   for(i = 0, dStrLen = 0; i <= len - 3; i += 3, dStrLen += 4){
      pDStr[dStrLen] = (pSStr[i]>>2)&0x3F;
      pDStr[dStrLen + 1] = (((pSStr[i]<<6)>>2)&0x30)|((pSStr[i + 1]>>4)&0x0F);
      pDStr[dStrLen + 2] = (((pSStr[i + 1]<<4)>>2)&0x3C)|((pSStr[i + 2]>>6)&0x03);
      pDStr[dStrLen + 3] = pSStr[i + 2]&0x3F;
   }
   if(0 != equ_num){
      unsigned char ch1 = ((2 == equ_num) ? pSStr[len - 2] : pSStr[len - 1]);
      unsigned char ch2 = ((2 == equ_num) ? pSStr[len - 1] : 0);
      pDStr[dStrLen++] = (ch1>>2)&0x3F;
      pDStr[dStrLen++] = (((ch1<<6)>>2)&0x30)|((ch2>>4)&0x0F);
      if(0 != ch2){
         pDStr[dStrLen++] = ((ch2<<4)>>2)&0x3C;
      }
   }
   for(i = 0; i < dStrLen; i++){
      pDStr[i] = Base64_EncodeTable[pDStr[i]];
   }
   if(0 != equ_num){
      if(1 == equ_num){
         pDStr[dStrLen++] = '=';
      }
      pDStr[dStrLen++] = '=';
   }
   pDStr[dStrLen] = 0;
   return dStrLen;
}

int Base64_Decode(unsigned char* pSStr, unsigned char* pDStr)
{
   int len = (int)strlen(reinterpret_cast<const char*>(pSStr));
   int dStrLen = 0;
   int i = 0;
   unsigned char ch1 = 0;
   unsigned char ch2 = 0;
   unsigned char ch3 = 0;
   unsigned char ch4 = 0;
   for(i = 0, dStrLen = 0; i < len; i += 4, dStrLen += 3){
      ch1 = Base64_DecodeTable[pSStr[i]];
      ch2 = Base64_DecodeTable[pSStr[i + 1]];
      ch3 = Base64_DecodeTable[pSStr[i + 2]];
      ch4 = Base64_DecodeTable[pSStr[i + 3]];
      pDStr[dStrLen] = ((ch1<<2)&0xFC)|((ch2>>4)&0x03);
      pDStr[dStrLen + 1] = ((ch2<<4)&0xF0)|((ch3>>2)&0x0F);
      pDStr[dStrLen + 2] = ((ch3<<6)&0xC0)|(ch4&0x3F);
   }
   pDStr[dStrLen] = 0;
   return dStrLen;
}