nkbin_maker/bsd-ce.c

#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

char*	outfile    = "nk.bin";
int	verbose = 0;
FILE*	fout = NULL;
FILE*	kfile = NULL;
FILE* lfile = NULL;
char* loader = NULL;
unsigned int loader_size = 0;

#define WRITE(arg,size) \
	if(!fwrite(arg, size, 1, fout)) \
		errx(1,"fwrite");

unsigned char  magic[7] = "B000FF\n";
unsigned int start = 0xa0200000;
unsigned int len   = 0;

void
usage(){
	fprintf(stderr, "usage: bsd-ce [-h] [-o outfile] u-boot.bin\n");
	fprintf(stderr, "\n");
	fprintf(stderr, "    -h                 this help\n");
	fprintf(stderr, "    -o outfile         write output to [outfile]\n");
	fprintf(stderr, "                       default: %s\n", outfile);
}

int
main(int argc, char* argv[]){
	int n, i;
	unsigned int i32, cksum, ch;
	long len;
	
	while((i = getopt(argc, argv, "hvo:l:")) != -1) {
		switch(i) {
			case 'o':
				outfile = optarg;
				break;
			case 'h':
			default:
				usage();
				return 1;
		}
	}
	argc -= optind; argv += optind;
	if (argc != 1) {
		fprintf(stderr, "missing kernel name\n");
		usage();
		return 1;
	}


	/* load the loader (err...) */
	if ((lfile = fopen(argv[0], "rb")) == NULL)
		errx(1, "unable to open '%s'", argv[0]);
	fseek(lfile, 0, SEEK_END);
	loader_size = ftell(lfile);
	fseek(lfile, 0, SEEK_SET);
	if ((loader = (char*)malloc(loader_size)) == NULL)
		errx(1, "can't allocate %u bytes for loader", loader_size);
	if (!fread(loader, loader_size, 1, lfile))
		errx(1, "can't read loader file");
	fclose(lfile);
	
	// next, try to create the output file
	if ((fout = fopen(outfile, "wb")) == NULL)
		errx(1, "unable to create '%s'", outfile);

	/*
   * Write NK.BIN header - this is a magic identifier, the first address
	 * data is stored, and the total length
	 */
	WRITE(magic,  sizeof(magic));
	WRITE(&start, sizeof(start));
	WRITE(&loader_size,  sizeof(loader_size));


	/* Calculate the loader checksum */
	cksum = 0;
	for (len = 0; len < loader_size; len++) {
		ch = (unsigned char)loader[len]; cksum += ch;
	}
	i32 = start;
	WRITE(&i32, sizeof(unsigned int));
	
	i32 = loader_size;
	WRITE(&i32, sizeof(unsigned int));
	
	i32 = cksum;
	WRITE(&i32, sizeof(unsigned int));

	/* Put the loader in place */
	for (len = 0; len < loader_size; len++) {
		putc(loader[len], fout);
	}

	/*
   * Write NK.BIN footer - this is just a series of 3x uint32_t indicating
	 * a file of zero length, starting at our init code.
	 */
	i32 = 0;       WRITE(&i32, sizeof(i32));
	i32 = start;   WRITE(&i32, sizeof(i32));
	i32 = 0;       WRITE(&i32, sizeof(i32));

	free(loader);
	fclose(fout);
	return 0;
}