MD5 從32位和16位互相進行轉換

程式碼如下：

程式碼塊

程式碼塊語法遵循標準markdown程式碼，例如：

// 16進位制字元轉10進位制
inline int hexToDec(char c) {
    int n;
    if (c >= '0' && c <= '9') {
        n = c - '0';
    } else {
        n = c - 'a' + 10;
    }

    return n;
}

// 一個char中有2個16進位制，轉為2個10進位制字元
inline void intDecToHex(unsigned
 
 char n, char* buf) {
    int t = 0;
    char c;
    t = n & 0x0f;
    if (t >=0 && t <= 9) {
        c = t + '0';
    } else {
        c = t - 10 + 'a';
    }
    buf[1] = c;

    n = n >> 4;
    t = n & 0x0f;
    if (t >=0 && t <= 9) {
        c = t + '0';
    } else
 
 {
        c = t - 10 + 'a';
    }
    buf[0] = c;
}

// 壓縮md5 32為 轉為16位
void encode32To16(const char* ori_str, unsigned char* out) {
    short index = 0;
    unsigned char tm;
    for (int i = 0; i < 32; ++index) {
        tm = 0;
        short n = hexToDec(ori_str[i++]);
        tm |= n;
        tm = tm << 4
 
;
        n = hexToDec(ori_str[i++]);
        tm |= n;
        out[index] = tm;
    }
    return;
}

// 16位壓縮md5轉為32位
void decode16To32(unsigned char* ori_str, char* out) {
    short index = 0;
    char buf[2] = {0};
    unsigned char tm;
    int index_ = 0;
    for (int i = 0; i < 16; ++i) {
        intDecToHex(ori_str[i], buf);
        out[index++] = buf[0];
        out[index++] = buf[1];
        index_ ++;
    }
    return;
}