disklabel.c

早期freebsd实现

	case ESRCH:
		fprintf(stderr, "No disk label on disk;\n");
		fprintf(stderr,
		    "use \"disklabel -r\" to install initial label\n");
		break;

	case EINVAL:
		fprintf(stderr, "Label magic number or checksum is wrong!\n");
		fprintf(stderr, "(disklabel or kernel is out of date?)\n");
		break;

	case EBUSY:
		fprintf(stderr, "Open partition would move or shrink\n");
		break;

	case EXDEV:
		fprintf(stderr,
	"Labeled partition or 'a' partition must start at beginning of disk\n");
		break;

	default:
		errno = saverrno;
		perror((char *)NULL);
		break;
	}
}

/*
 * Fetch disklabel for disk.
 * Use ioctl to get label unless -r flag is given.
 */
struct disklabel *
readlabel(f)
	int f;
{
	register struct disklabel *lp;

	if (rflag) {
		if (read(f, bootarea, BBSIZE) < BBSIZE)
			Perror(specname);
		for (lp = (struct disklabel *)bootarea;
		    lp <= (struct disklabel *)(bootarea + BBSIZE - sizeof(*lp));
		    lp = (struct disklabel *)((char *)lp + 16))
			if (lp->d_magic == DISKMAGIC &&
			    lp->d_magic2 == DISKMAGIC)
				break;
		if (lp > (struct disklabel *)(bootarea+BBSIZE-sizeof(*lp)) ||
		    lp->d_magic != DISKMAGIC || lp->d_magic2 != DISKMAGIC ||
		    dkcksum(lp) != 0) {
			fprintf(stderr,
	"Bad pack magic number (label is damaged, or pack is unlabeled)\n");
			/* lp = (struct disklabel *)(bootarea + LABELOFFSET); */
			exit (1);
		}
	} else {
		lp = &lab;
		if (ioctl(f, DIOCGDINFO, lp) < 0)
			Perror("ioctl DIOCGDINFO");
	}
	return (lp);
}

/*
 * Construct a bootarea (d_bbsize bytes) in the specified buffer ``boot''
 * Returns a pointer to the disklabel portion of the bootarea.
 */
struct disklabel *
makebootarea(boot, dp, f)
	char *boot;
	register struct disklabel *dp;
	int f;
{
	struct disklabel *lp;
	register char *p;
	int b;
#if NUMBOOT > 0
	char *dkbasename;
	struct stat sb;
#endif

	/* XXX */
	if (dp->d_secsize == 0) {
		dp->d_secsize = DEV_BSIZE;
		dp->d_bbsize = BBSIZE;
	}
	lp = (struct disklabel *)
		(boot + (LABELSECTOR * dp->d_secsize) + LABELOFFSET);
	bzero((char *)lp, sizeof *lp);
#if NUMBOOT > 0
	/*
	 * If we are not installing a boot program but we are installing a
	 * label on disk then we must read the current bootarea so we don't
	 * clobber the existing boot.
	 */
	if (!installboot) {
		if (rflag) {
			if (read(f, boot, BBSIZE) < BBSIZE)
				Perror(specname);
			bzero((char *)lp, sizeof *lp);
		}
		return (lp);
	}
	/*
	 * We are installing a boot program.  Determine the name(s) and
	 * read them into the appropriate places in the boot area.
	 */
	if (!xxboot || !bootxx) {
		dkbasename = np;
		if ((p = rindex(dkname, '/')) == NULL)
			p = dkname;
		else
			p++;
		while (*p && !isdigit(*p))
			*np++ = *p++;
		*np++ = '\0';

		if (!xxboot) {
			(void)sprintf(np, "%s/%sboot",
				      _PATH_BOOTDIR, dkbasename);
			if (access(np, F_OK) < 0 && dkbasename[0] == 'r')
				dkbasename++;
			xxboot = np;
			(void)sprintf(xxboot, "%s/%sboot",
				      _PATH_BOOTDIR, dkbasename);
			np += strlen(xxboot) + 1;
		}
#if NUMBOOT > 1
		if (!bootxx) {
			(void)sprintf(np, "%s/boot%s",
				      _PATH_BOOTDIR, dkbasename);
			if (access(np, F_OK) < 0 && dkbasename[0] == 'r')
				dkbasename++;
			bootxx = np;
			(void)sprintf(bootxx, "%s/boot%s",
				      _PATH_BOOTDIR, dkbasename);
			np += strlen(bootxx) + 1;
		}
#endif
	}
#ifdef DEBUG
	if (debug)
		fprintf(stderr, "bootstraps: xxboot = %s, bootxx = %s\n",
			xxboot, bootxx ? bootxx : "NONE");
#endif

	/*
	 * Strange rules:
	 * 1. One-piece bootstrap (hp300/hp800)
	 *	up to d_bbsize bytes of ``xxboot'' go in bootarea, the rest
	 *	is remembered and written later following the bootarea.
	 * 2. Two-piece bootstraps (vax/i386?/mips?)
	 *	up to d_secsize bytes of ``xxboot'' go in first d_secsize
	 *	bytes of bootarea, remaining d_bbsize-d_secsize filled
	 *	from ``bootxx''.
	 */
	b = open(xxboot, O_RDONLY);
	if (b < 0)
		Perror(xxboot);
#if NUMBOOT > 1
	if (read(b, boot, (int)dp->d_secsize) < 0)
		Perror(xxboot);
	(void)close(b);
	b = open(bootxx, O_RDONLY);
	if (b < 0)
		Perror(bootxx);
	if (read(b, &boot[dp->d_secsize], (int)(dp->d_bbsize-dp->d_secsize)) < 0)
		Perror(bootxx);
#else
	if (read(b, boot, (int)dp->d_bbsize) < 0)
		Perror(xxboot);
	(void)fstat(b, &sb);
	bootsize = (int)sb.st_size - dp->d_bbsize;
	if (bootsize > 0) {
		/* XXX assume d_secsize is a power of two */
		bootsize = (bootsize + dp->d_secsize-1) & ~(dp->d_secsize-1);
		bootbuf = (char *)malloc((size_t)bootsize);
		if (bootbuf == 0)
			Perror(xxboot);
		if (read(b, bootbuf, bootsize) < 0) {
			free(bootbuf);
			Perror(xxboot);
		}
	}
#endif
	(void)close(b);
#endif
	/*
	 * Make sure no part of the bootstrap is written in the area
	 * reserved for the label.
	 */
	for (p = (char *)lp; p < (char *)lp + sizeof(struct disklabel); p++)
		if (*p) {
			fprintf(stderr,
			    "Bootstrap doesn't leave room for disk label\n");
			exit(2);
		}
	return (lp);
}

display(f, lp)
	FILE *f;
	register struct disklabel *lp;
{
	register int i, j;
	register struct partition *pp;

	fprintf(f, "# %s:\n", specname);
	if ((unsigned) lp->d_type < DKMAXTYPES)
		fprintf(f, "type: %s\n", dktypenames[lp->d_type]);
	else
		fprintf(f, "type: %d\n", lp->d_type);
	fprintf(f, "disk: %.*s\n", sizeof(lp->d_typename), lp->d_typename);
	fprintf(f, "label: %.*s\n", sizeof(lp->d_packname), lp->d_packname);
	fprintf(f, "flags:");
	if (lp->d_flags & D_REMOVABLE)
		fprintf(f, " removeable");
	if (lp->d_flags & D_ECC)
		fprintf(f, " ecc");
	if (lp->d_flags & D_BADSECT)
		fprintf(f, " badsect");
	fprintf(f, "\n");
	fprintf(f, "bytes/sector: %d\n", lp->d_secsize);
	fprintf(f, "sectors/track: %d\n", lp->d_nsectors);
	fprintf(f, "tracks/cylinder: %d\n", lp->d_ntracks);
	fprintf(f, "sectors/cylinder: %d\n", lp->d_secpercyl);
	fprintf(f, "cylinders: %d\n", lp->d_ncylinders);
	fprintf(f, "rpm: %d\n", lp->d_rpm);
	fprintf(f, "interleave: %d\n", lp->d_interleave);
	fprintf(f, "trackskew: %d\n", lp->d_trackskew);
	fprintf(f, "cylinderskew: %d\n", lp->d_cylskew);
	fprintf(f, "headswitch: %d\t\t# milliseconds\n", lp->d_headswitch);
	fprintf(f, "track-to-track seek: %d\t# milliseconds\n", lp->d_trkseek);
	fprintf(f, "drivedata: ");
	for (i = NDDATA - 1; i >= 0; i--)
		if (lp->d_drivedata[i])
			break;
	if (i < 0)
		i = 0;
	for (j = 0; j <= i; j++)
		fprintf(f, "%d ", lp->d_drivedata[j]);
	fprintf(f, "\n\n%d partitions:\n", lp->d_npartitions);
	fprintf(f,
	    "#        size   offset    fstype   [fsize bsize   cpg]\n");
	pp = lp->d_partitions;
	for (i = 0; i < lp->d_npartitions; i++, pp++) {
		if (pp->p_size) {
			fprintf(f, "  %c: %8d %8d  ", 'a' + i,
			   pp->p_size, pp->p_offset);
			if ((unsigned) pp->p_fstype < FSMAXTYPES)
				fprintf(f, "%8.8s", fstypenames[pp->p_fstype]);
			else
				fprintf(f, "%8d", pp->p_fstype);
			switch (pp->p_fstype) {

			case FS_UNUSED:				/* XXX */
				fprintf(f, "    %5d %5d %5.5s ",
				    pp->p_fsize, pp->p_fsize * pp->p_frag, "");
				break;

			case FS_BSDFFS:
				fprintf(f, "    %5d %5d %5d ",
				    pp->p_fsize, pp->p_fsize * pp->p_frag,
				    pp->p_cpg);
				break;

			default:
				fprintf(f, "%20.20s", "");
				break;
			}
			fprintf(f, "\t# (Cyl. %4d",
			    pp->p_offset / lp->d_secpercyl);
			if (pp->p_offset % lp->d_secpercyl)
			    putc('*', f);
			else
			    putc(' ', f);
			fprintf(f, "- %d",
			    (pp->p_offset + 
			    pp->p_size + lp->d_secpercyl - 1) /
			    lp->d_secpercyl - 1);
			if (pp->p_size % lp->d_secpercyl)
			    putc('*', f);
			fprintf(f, ")\n");
		}
	}
	fflush(f);
}

edit(lp, f)
	struct disklabel *lp;
	int f;
{
	register int c;
	struct disklabel label;
	FILE *fd;
	char *mktemp();

	(void) mktemp(tmpfil);
	fd = fopen(tmpfil, "w");
	if (fd == NULL) {
		fprintf(stderr, "%s: Can't create\n", tmpfil);
		return (1);
	}
	(void)fchmod(fileno(fd), 0600);
	display(fd, lp);
	fclose(fd);
	for (;;) {
		if (!editit())
			break;
		fd = fopen(tmpfil, "r");
		if (fd == NULL) {
			fprintf(stderr, "%s: Can't reopen for reading\n",
				tmpfil);
			break;
		}
		bzero((char *)&label, sizeof(label));
		if (getasciilabel(fd, &label)) {
			*lp = label;
			if (writelabel(f, bootarea, lp) == 0) {
				(void) unlink(tmpfil);
				return (0);
			}
		}
		printf("re-edit the label? [y]: "); fflush(stdout);
		c = getchar();
		if (c != EOF && c != (int)'\n')
			while (getchar() != (int)'\n')
				;
		if  (c == (int)'n')
			break;
	}
	(void) unlink(tmpfil);
	return (1);
}

editit()
{
	register int pid, xpid;
	int stat, omask;
	extern char *getenv();

	omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
	while ((pid = fork()) < 0) {
		extern int errno;

		if (errno == EPROCLIM) {
			fprintf(stderr, "You have too many processes\n");
			return(0);
		}
		if (errno != EAGAIN) {
			perror("fork");
			return(0);
		}
		sleep(1);
	}
	if (pid == 0) {
		register char *ed;

		sigsetmask(omask);
		setgid(getgid());
		setuid(getuid());
		if ((ed = getenv("EDITOR")) == (char *)0)
			ed = DEFEDITOR;
		execlp(ed, ed, tmpfil, 0);
		perror(ed);
		exit(1);
	}
	while ((xpid = wait(&stat)) >= 0)
		if (xpid == pid)
			break;
	sigsetmask(omask);
	return(!stat);
}

char *
skip(cp)
	register char *cp;
{

	while (*cp != '\0' && isspace(*cp))
		cp++;
	if (*cp == '\0' || *cp == '#')
		return ((char *)NULL);
	return (cp);
}

char *
word(cp)
	register char *cp;
{
	register char c;

	while (*cp != '\0' && !isspace(*cp) && *cp != '#')
		cp++;
	if ((c = *cp) != '\0') {
		*cp++ = '\0';
		if (c != '#')
			return (skip(cp));
	}
	return ((char *)NULL);
}

/*
 * Read an ascii label in from fd f,
 * in the same format as that put out by display(),
 * and fill in lp.
 */
getasciilabel(f, lp)
	FILE	*f;
	register struct disklabel *lp;
{
	register char **cpp, *cp;
	register struct partition *pp;
	char *tp, *s, line[BUFSIZ];
	int v, lineno = 0, errors = 0;

	lp->d_bbsize = BBSIZE;				/* XXX */
	lp->d_sbsize = SBSIZE;				/* XXX */
	while (fgets(line, sizeof(line) - 1, f)) {
		lineno++;
		if (cp = index(line,'\n'))
			*cp = '\0';
		cp = skip(line);
		if (cp == NULL)
			continue;
		tp = index(cp, ':');
		if (tp == NULL) {
			fprintf(stderr, "line %d: syntax error\n", lineno);
			errors++;
			continue;
		}
		*tp++ = '\0', tp = skip(tp);
		if (streq(cp, "type")) {
			if (tp == NULL)
				tp = "unknown";
			cpp = dktypenames;
			for (; cpp < &dktypenames[DKMAXTYPES]; cpp++)
				if ((s = *cpp) && streq(s, tp)) {
					lp->d_type = cpp - dktypenames;
					goto next;