#include <stdio.h>

unsigned long Ch(x, y, z)
 unsigned long x, y, z;
{
	return((x&y)^(~x&z));
}

unsigned long Maj(x, y, z)
 unsigned long x, y, z;
{
	return((x&y)^(x&z)^(y&z));
}

unsigned long ROTR(x, n)
 unsigned long x;
 int n;
{

	if (n < 33)
		return ((x >> n) | (x << (32-n)));
	else
		return (0);
}

unsigned long SHR(x, n)
 unsigned long x;
 int	n;
 {
	 return (x >> n);
 }

unsigned long Sigma0(x)
 unsigned long x;
{
	return(ROTR(x,2) ^ ROTR(x, 13) ^ ROTR(x,22));
}

unsigned long Sigma1(x)
 unsigned long x;
{
	return(ROTR(x, 6) ^ ROTR(x,11) ^ ROTR(x, 25));
}

unsigned long sigma2(x)
 unsigned long x;
{
	return(ROTR(x,7) ^ ROTR(x, 18) ^ SHR(x, 3));
}

unsigned long H[8], T1, T2, a, b, c, d, e, f, g, h, w[64];


unsigned long sigma3(x)
 unsigned long x;
{
	return(ROTR(x, 17) ^ ROTR(x, 19) ^ SHR(x, 10));
}


unsigned long const k[64] = 
{0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2};

unsigned long const mask = 0x80000000;


int bitset(offset)
 int offset;
 {
	 if ((H[offset/32] & (mask >> (offset%32))) > 0)
		return (1);
	 else
		 return(0);
 }


main(argc, argv)
int  argc;
char *argv[];
{
 int    counter;
 FILE	*ptr;
 if argc == 2 {
  if (ptr = fopen(argv[1],"r") == NULL)
	{ printf("File %s not found\n", argv[1]);
	  exit(0); }
  else
	{ Printf("Requires a second argument identifying what file to open\n");
	  exit(0); }
	}
	 H[0] = 0x6a09e667;
	 H[1] = 0xbb67ae85;
	 H[2] = 0x3c6ef372;
	 H[3] = 0xa54ff53a;
	 H[4] = 0x510e527f;
	 H[5] = 0x9b05688c;
	 H[6] = 0x1f83d9ab;
	 H[7] = 0x5be0cd19;


	unsigned count, i, j, index, last_block=0, done=0;
	char	temp;
	unsigned long bit_count = 0;
	unsligned long temp_word;
	

	for (i=0; i<16; i++)
	  w[i] = 0;
     if (last_block = 1) /* last block is for values greater that 448 */
	{ done = 1;
	  if (count == 448) /* special condition need to add 1 to first bit of next block */
	    w[0] = mask;
	  w[15] = bit_count; }
     else
	for (i =0; i<16; i++) {
	  for (j=0, temp_word =0; j<4,count==0,last_block==0; j++ {
	    if ((feof(temp = fgetc(fp))) /* test for end of file */
	      { temp_word += (unsigned long)(0x80 << ((3 - j)*8)); /* position byte */
	        if (done = 0)
	          if(count < 448)
	           done = 1; /* can finish using current block */
	         else
	           last_block = 1; /* needs to pad the next block */
	      }
	    else
	      { temp_word += (unsigned long)(temp << ((3 - j)*8)); 
	        count += 8; /* for each byte loaded = 8-bits */
	      }
	      
	      
	  }
	 if (done == 0)
	   w[i] = temp_word; /* Load in the next word */

	}
	bit_count += count; /* add in the number of bits */
	
	 for (index =16; index < 64; index++)
		 w[index] = sigma3(w[index-2]) + w[index-7] + sigma2(w[index-15]) + w[index-16];
	a = H[0];
	b = H[1];
	c = H[2];
	d = H[3];
	e = H[4];
	f = H[5];
	g = H[6];
	h = H[7];
	for (count = 0; count < 64; count++)
	{
		T1 = h + Sigma1(e) + Ch(e,f,g) + k[count] + w[count];
		T2 = Sigma0(a) + Maj(a,b,c);
		h = g;
		g = f;
		f = e;
		e = d + T1;
		d = c;
		c = b;
		b = a;
		a = T1 + T2;
	/*	printf("t=%d %08x %08x %08x %08x %08x %08x %08x %08x\n",count, a,b,c,d,e,f,g,h); */
	}
	H[0] += a;
	H[1] += b;
	H[2] += c;
	H[3] += d;
	H[4] += e;
	H[5] += f;
	H[6] += g;
	H[7] += h;
	if (done == 1) {
	  printf("Message Digest %08x %08x %08x %08x %08x %08x %08x %08x\n",H[0],H[1],H[2],H[3],H[4],H[5],H[6],H[7]);
	  fclose(ptr); /* close the open file */
	  exit(0); } /* end the program */

	}
}