#ifndef MD5_H
#define MD5_H
/*
Function: md5_32校验
Size: 大约为2.5KB
Note: 使用memcpy，自行衡量内存空间
Example:
    MD5_CTX md5;     
    unsigned char encrypt[16]="123456";//需要散列的内容
    unsigned char decrypt[16];//md5(123456,32) = e10adc3949ba59abbe56e057f20f883e   
    MD5Init(&md5); 
    MD5Update(&md5,encrypt,strlen((char *)encrypt));
    MD5Final(&md5,decrypt);
    for(i=0;i<16;i++){
        printf("%02x",decrypt[i]);
    }
*/
typedef struct{
    unsigned int count[2];
    unsigned int state[4];
    unsigned char buffer[64];   
}MD5_CTX;
 
 
#define F(x,y,z) ((x & y) | (~x & z))
#define G(x,y,z) ((x & z) | (y & ~z))
#define H(x,y,z) (x^y^z)
#define I(x,y,z) (y ^ (x | ~z))
#define ROTATE_LEFT(x,n) ((x << n) | (x >> (32-n)))
#define FF(a,b,c,d,x,s,ac) \
{ \
    a += F(b,c,d) + x + ac; \
    a = ROTATE_LEFT(a,s); \
    a += b; \
}
#define GG(a,b,c,d,x,s,ac) \
{ \
    a += G(b,c,d) + x + ac; \
    a = ROTATE_LEFT(a,s); \
    a += b; \
}
#define HH(a,b,c,d,x,s,ac) \
{ \
    a += H(b,c,d) + x + ac; \
    a = ROTATE_LEFT(a,s); \
    a += b; \
}
#define II(a,b,c,d,x,s,ac) \
{ \
    a += I(b,c,d) + x + ac; \
    a = ROTATE_LEFT(a,s); \
    a += b; \
}                                            
void MD5Init(MD5_CTX *context);
void MD5Update(MD5_CTX *context,unsigned char *input,unsigned int inputlen);
void MD5Final(MD5_CTX *context,unsigned char digest[16]);
void MD5Transform(unsigned int state[4],unsigned char block[64]);
void MD5Encode(unsigned char *output,unsigned int *input,unsigned int len);
void MD5Decode(unsigned int *output,unsigned char *input,unsigned int len);
 
#endif