#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>

#include <unistd.h>
#include <fcntl.h>
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/filio.h>
#include <err.h>
#include <util.h>

#if DEV_BSIZE != 512
#error "unexpected DEV_BSIZE"
#endif

#define	FMT_BASE	"o %12"PRId64" %12"PRId64" l %6"PRId64" %6"PRId64" p %10"PRId64" %10"PRId64
#define	FMT_SEEK	FMT_BASE " s %10"PRId64"\n"
#define	FMT_END		FMT_BASE "\n"

int
main(int argc, char *argv[])
{
	int fd;
	int debug;
	int error;
	daddr_t nblks;
	struct statvfs stfs;
	struct stat st;
	daddr_t lbn, pbn, off;
	daddr_t runlbn, runpbn, runoff;
	daddr_t prev;

	if (argc < 2)
		errx(EXIT_FAILURE, "usage: %s diskdev DEBUG", getprogname());

	debug = argc > 2;

	fd = open(argv[1], O_RDONLY, 0);
	if (fd == -1)
		err(EXIT_FAILURE, "open %s", argv[1]);

	error = fstatvfs(fd, &stfs);
	if (error == -1)
		err(EXIT_FAILURE, "fstatfs");

	error = fstat(fd, &st);
	if (error == -1)
		err(EXIT_FAILURE, "fstatfs");

	nblks = howmany(st.st_size, st.st_blksize);

	setbuf(stdout, NULL);

	if (debug) {
		fprintf(stderr, "st.st_size: %"PRIu64"\n", (uint64_t)st.st_size);
		fprintf(stderr, "st.st_blocks: %"PRId64"\n", st.st_blocks);
		fprintf(stderr, "st.st_blksize: %d\n", st.st_blksize);
		fprintf(stderr, "stfs.f_bsize: %ld\n", stfs.f_bsize);
		fprintf(stderr, "nlks: %"PRId64" * %d = %"PRId64"\n", nblks, st.st_blksize, nblks * st.st_blksize);
	}

	for (off = 0, lbn = 0; lbn < nblks; off += st.st_blksize, lbn++) {
		daddr_t addr;

		addr = lbn;
		error = ioctl(fd, FIOGETBMAP, &addr);
		if (error == -1)
			err(EXIT_FAILURE, "ioctl FIOGETBMAP");
		pbn = addr;

		if (lbn == 0) {
			runlbn = lbn;
			runoff = off;
			runpbn = pbn;
		} else if ((pbn != prev + howmany(st.st_blksize, DEV_BSIZE)) && !(pbn == -1 && prev == -1)) {
			printf(FMT_SEEK, runoff, MIN(off, st.st_size) - runoff,
			    runlbn, lbn - runlbn, runpbn,
			    prev < 0 ? howmany(MIN(off, st.st_size) - runoff, DEV_BSIZE) :
			    (prev + MIN(howmany(st.st_blksize, DEV_BSIZE), howmany((st.st_blocks*512), DEV_BSIZE)) - runpbn),
			    pbn - (prev + howmany(st.st_blksize, DEV_BSIZE)));
			runoff = off;
			runlbn = lbn;
			runpbn = pbn;
		}
		if (debug) {
			fprintf(stderr, "FIOGETBMAP: o: %16"PRId64" l: %16"PRId64" p: %16"PRId64"\n",
			    off, lbn, pbn);
		}
		prev = pbn;
	}
	printf(FMT_END, runoff, MIN(off, st.st_size) - runoff, runlbn, lbn - runlbn, runpbn,
	    prev < 0 ? 0 : prev + MIN(howmany(st.st_blksize, DEV_BSIZE), howmany((st.st_blocks*512), DEV_BSIZE)) - runpbn);

	error = close(fd);
	if (error == -1)
		err(EXIT_FAILURE, "close");

	return EXIT_SUCCESS;
}