#include <stdio.h>

 #include <stdlib.h>

 #include <sm_crc32.h>

 int main(int argc, char **argv)

 {

 	if (argc < 2)

 	{

 		fprintf(stderr, "Usage: crc32 <file>\n");

 		exit(1);

 	}

 	FILE *fp = fopen(argv[1], "rb");

 	if (!fp)

 	{

 		fprintf(stderr, "Could not open file: %s\n", argv[1]);

 		exit(1);

 	}

 	fseek(fp, 0, SEEK_END);

 	size_t size = ftell(fp);	

 	if (!size)

 	{

 		fprintf(stderr, "Cannot checksum an empty file.\n");

 		exit(1);

 	}

 	fseek(fp, 0, SEEK_SET);

 	void *buffer = malloc(size);

 	if (!buffer)

 	{

 		fprintf(stderr, "Unable to allocate %d bytes of memory.\n", size);

 		exit(1);

 	}

 	fread(buffer, size, 1, fp);

 	unsigned int crc32 = UTIL_CRC32(buffer, size);

 	free(buffer);

 	fclose(fp);

 	fprintf(stdout, "%08X\n", crc32);

 	return 0;

 }