#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;

}