fdisk.c

Util-linux 软件包包含许多工具。其中比较重要的是加载、卸载、格式化、分区和管理硬盘驱动器

		 hex = hex << 4 | hex_val(*line_ptr++);
	      while (isxdigit(*line_ptr));
	      return hex;
	   }
        }
}

/*
 * Print the message MESG, then read an integer in LOW..HIGH.
 * If the user hits Enter, DFLT is returned, provided that is in LOW..HIGH.
 * Answers like +10 are interpreted as offsets from BASE.
 *
 * There is no default if DFLT is not between LOW and HIGH.
 */
unsigned int
read_int(unsigned int low, unsigned int dflt, unsigned int high,
	 unsigned int base, char *mesg)
{
	unsigned int i;
	int default_ok = 1;
	static char *ms = NULL;
	static int mslen = 0;

	if (!ms || strlen(mesg)+100 > mslen) {
		mslen = strlen(mesg)+200;
		if (!(ms = realloc(ms,mslen)))
			fatal(out_of_memory);
	}

	if (dflt < low || dflt > high)
		default_ok = 0;

	if (default_ok)
		snprintf(ms, mslen, _("%s (%u-%u, default %u): "),
			 mesg, low, high, dflt);
	else
		snprintf(ms, mslen, "%s (%u-%u): ",
			 mesg, low, high);

	while (1) {
		int use_default = default_ok;

		/* ask question and read answer */
		while (read_chars(ms) != '\n' && !isdigit(*line_ptr)
		       && *line_ptr != '-' && *line_ptr != '+')
			continue;

		if (*line_ptr == '+' || *line_ptr == '-') {
			int minus = (*line_ptr == '-');
			int absolute = 0;

			i = atoi(line_ptr+1);

 			while (isdigit(*++line_ptr))
				use_default = 0;

			switch (*line_ptr) {
				case 'c':
				case 'C':
					if (!display_in_cyl_units)
						i *= heads * sectors;
					break;
				case 'K':
					absolute = 1024;
					break;
				case 'k':
					absolute = 1000;
					break;
				case 'm':
				case 'M':
					absolute = 1000000;
					break;
				case 'g':
				case 'G':
					absolute = 1000000000;
					break;
				default:
					break;
			}
			if (absolute) {
				unsigned long long bytes;
				unsigned long unit;

				bytes = (unsigned long long) i * absolute;
				unit = sector_size * units_per_sector;
				bytes += unit/2;	/* round */
				bytes /= unit;
				i = bytes;
			}
			if (minus)
				i = -i;
			i += base;
		} else {
			i = atoi(line_ptr);
			while (isdigit(*line_ptr)) {
				line_ptr++;
				use_default = 0;
			}
		}
		if (use_default)
			printf(_("Using default value %u\n"), i = dflt);
		if (i >= low && i <= high)
			break;
		else
			printf(_("Value out of range.\n"));
	}
	return i;
}

int
get_partition(int warn, int max) {
	struct pte *pe;
	int i;

	i = read_int(1, 0, max, 0, _("Partition number")) - 1;
	pe = &ptes[i];

	if (warn) {
		if ((!sun_label && !sgi_label && !pe->part_table->sys_ind)
		    || (sun_label &&
			(!sunlabel->partitions[i].num_sectors ||
			 !sunlabel->infos[i].id))
		    || (sgi_label && (!sgi_get_num_sectors(i)))
		   )
			fprintf(stderr,
				_("Warning: partition %d has empty type\n"),
				i+1);
	}
	return i;
}

static int
get_existing_partition(int warn, int max) {
	int pno = -1;
	int i;

	for (i = 0; i < max; i++) {
		struct pte *pe = &ptes[i];
		struct partition *p = pe->part_table;

		if (p && !is_cleared_partition(p)) {
			if (pno >= 0)
				goto not_unique;
			pno = i;
		}
	}
	if (pno >= 0) {
		printf(_("Selected partition %d\n"), pno+1);
		return pno;
	}
	printf(_("No partition is defined yet!\n"));
	return -1;

 not_unique:
	return get_partition(warn, max);
}

static int
get_nonexisting_partition(int warn, int max) {
	int pno = -1;
	int i;

	for (i = 0; i < max; i++) {
		struct pte *pe = &ptes[i];
		struct partition *p = pe->part_table;

		if (p && is_cleared_partition(p)) {
			if (pno >= 0)
				goto not_unique;
			pno = i;
		}
	}
	if (pno >= 0) {
		printf(_("Selected partition %d\n"), pno+1);
		return pno;
	}
	printf(_("All primary partitions have been defined already!\n"));
	return -1;

 not_unique:
	return get_partition(warn, max);
}

char * const
str_units(int n) {	/* n==1: use singular */
	if (n == 1)
		return display_in_cyl_units ? _("cylinder") : _("sector");
	else
		return display_in_cyl_units ? _("cylinders") : _("sectors");
}

void change_units(void)
{
	display_in_cyl_units = !display_in_cyl_units;
	update_units();
	printf(_("Changing display/entry units to %s\n"),
		str_units(PLURAL));
}

static void
toggle_active(int i) {
	struct pte *pe = &ptes[i];
	struct partition *p = pe->part_table;

	if (IS_EXTENDED (p->sys_ind) && !p->boot_ind)
		fprintf(stderr,
			_("WARNING: Partition %d is an extended partition\n"),
			i + 1);
	p->boot_ind = (p->boot_ind ? 0 : ACTIVE_FLAG);
	pe->changed = 1;
}

static void
toggle_dos_compatibility_flag(void) {
	dos_compatible_flag = ~dos_compatible_flag;
	if (dos_compatible_flag) {
		sector_offset = sectors;
		printf(_("DOS Compatibility flag is set\n"));
	}
	else {
		sector_offset = 1;
		printf(_("DOS Compatibility flag is not set\n"));
	}
}

static void
delete_partition(int i) {
	struct pte *pe = &ptes[i];
	struct partition *p = pe->part_table;
	struct partition *q = pe->ext_pointer;

/* Note that for the fifth partition (i == 4) we don't actually
 * decrement partitions.
 */

	if (warn_geometry())
		return;		/* C/H/S not set */
	pe->changed = 1;

	if (sun_label) {
		sun_delete_partition(i);
		return;
	}

	if (sgi_label) {
		sgi_delete_partition(i);
		return;
	}

	if (i < 4) {
		if (IS_EXTENDED (p->sys_ind) && i == ext_index) {
			partitions = 4;
			ptes[ext_index].ext_pointer = NULL;
			extended_offset = 0;
		}
		clear_partition(p);
		return;
	}

	if (!q->sys_ind && i > 4) {
		/* the last one in the chain - just delete */
		--partitions;
		--i;
		clear_partition(ptes[i].ext_pointer);
		ptes[i].changed = 1;
	} else {
		/* not the last one - further ones will be moved down */
		if (i > 4) {
			/* delete this link in the chain */
			p = ptes[i-1].ext_pointer;
			*p = *q;
			set_start_sect(p, get_start_sect(q));
			set_nr_sects(p, get_nr_sects(q));
			ptes[i-1].changed = 1;
		} else if (partitions > 5) {    /* 5 will be moved to 4 */
			/* the first logical in a longer chain */
			struct pte *pe = &ptes[5];

			if (pe->part_table) /* prevent SEGFAULT */
				set_start_sect(pe->part_table,
					       get_partition_start(pe) -
					       extended_offset);
			pe->offset = extended_offset;
			pe->changed = 1;
		}

		if (partitions > 5) {
			partitions--;
			while (i < partitions) {
				ptes[i] = ptes[i+1];
				i++;
			}
		} else
			/* the only logical: clear only */
			clear_partition(ptes[i].part_table);
	}
}

static void
change_sysid(void) {
	char *temp;
	int i, sys, origsys;
	struct partition *p;

	/* If sgi_label then don't use get_existing_partition,
	   let the user select a partition, since get_existing_partition()
	   only works for Linux like partition tables. */
	if (!sgi_label) { 
		i = get_existing_partition(0, partitions);
	} else {
		i = get_partition(0, partitions);
	}

	if (i == -1)
		return;
	p = ptes[i].part_table;
	origsys = sys = get_sysid(i);

	/* if changing types T to 0 is allowed, then
	   the reverse change must be allowed, too */
	if (!sys && !sgi_label && !sun_label && !get_nr_sects(p))
                printf(_("Partition %d does not exist yet!\n"), i + 1);
        else while (1) {
		sys = read_hex (get_sys_types());

		if (!sys && !sgi_label && !sun_label) {
			printf(_("Type 0 means free space to many systems\n"
			       "(but not to Linux). Having partitions of\n"
			       "type 0 is probably unwise. You can delete\n"
			       "a partition using the `d' command.\n"));
			/* break; */
		}

		if (!sun_label && !sgi_label) {
			if (IS_EXTENDED (sys) != IS_EXTENDED (p->sys_ind)) {
				printf(_("You cannot change a partition into"
				       " an extended one or vice versa\n"
				       "Delete it first.\n"));
				break;
			}
		}

                if (sys < 256) {
			if (sun_label && i == 2 && sys != WHOLE_DISK)
				printf(_("Consider leaving partition 3 "
				       "as Whole disk (5),\n"
				       "as SunOS/Solaris expects it and "
				       "even Linux likes it.\n\n"));
			if (sgi_label && ((i == 10 && sys != ENTIRE_DISK)
					  || (i == 8 && sys != 0)))
				printf(_("Consider leaving partition 9 "
				       "as volume header (0),\nand "
				       "partition 11 as entire volume (6)"
				       "as IRIX expects it.\n\n"));
                        if (sys == origsys)
				break;
			if (sun_label) {
				sun_change_sysid(i, sys);
			} else
			if (sgi_label) {
				sgi_change_sysid(i, sys);
			} else
				p->sys_ind = sys;
                        printf (_("Changed system type of partition %d "
                                "to %x (%s)\n"), i + 1, sys,
                                (temp = partition_type(sys)) ? temp :
                                _("Unknown"));
                        ptes[i].changed = 1;
			if (is_dos_partition(origsys) ||
			    is_dos_partition(sys))
				dos_changed = 1;
                        break;
                }
        }
}

/* check_consistency() and long2chs() added Sat Mar 6 12:28:16 1993,
 * [e-mail], based on code fragments from pfdisk by Gordon W. Ross,
 * Jan.  1990 (version 1.2.1 by Gordon W. Ross Aug. 1990; Modified by S.
 * Lubkin Oct.  1991). */

static void
long2chs(ulong ls, unsigned int *c, unsigned int *h, unsigned int *s) {
	int spc = heads * sectors;

	*c = ls / spc;
	ls = ls % spc;
	*h = ls / sectors;
	*s = ls % sectors + 1;	/* sectors count from 1 */
}

static void check_consistency(struct partition *p, int partition) {
	unsigned int pbc, pbh, pbs;	/* physical beginning c, h, s */
	unsigned int pec, peh, pes;	/* physical ending c, h, s */
	unsigned int lbc, lbh, lbs;	/* logical beginning c, h, s */
	unsigned int lec, leh, les;	/* logical ending c, h, s */

	if (!heads || !sectors || (partition >= 4))
		return;		/* do not check extended partitions */

/* physical beginning c, h, s */
	pbc = (p->cyl & 0xff) | ((p->sector << 2) & 0x300);
	pbh = p->head;
	pbs = p->sector & 0x3f;

/* physical ending c, h, s */
	pec = (p->end_cyl & 0xff) | ((p->end_sector << 2) & 0x300);
	peh = p->end_head;
	pes = p->end_sector & 0x3f;

/* compute logical beginning (c, h, s) */
	long2chs(get_start_sect(p), &lbc, &lbh, &lbs);

/* compute logical ending (c, h, s) */
	long2chs(get_start_sect(p) + get_nr_sects(p) - 1, &lec, &leh, &les);

/* Same physical / logical beginning? */
	if (cylinders <= 1024 && (pbc != lbc || pbh != lbh || pbs != lbs)) {
		printf(_("Partition %d has different physical/logical "
			"beginnings (non-Linux?):\n"), partition + 1);
		printf(_("     phys=(%d, %d, %d) "), pbc, pbh, pbs);
		printf(_("logical=(%d, %d, %d)\n"),lbc, lbh, lbs);
	}

/* Same physical / logical ending? */
	if (cylinders <= 1024 && (pec != lec || peh != leh || pes != les)) {
		printf(_("Partition %d has different physical/logical "
			"endings:\n"), partition + 1);
		printf(_("     phys=(%d, %d, %d) "), pec, peh, pes);
		printf(_("logical=(%d, %d, %d)\n"),lec, leh, les);
	}

#if 0
/* Beginning on cylinder boundary? */
	if (pbh != !pbc || pbs != 1) {
		printf(_("Partition %i does not start on cylinder "
			"boundary:\n"), partition + 1);
		printf(_("     phys=(%d, %d, %d) "), pbc, pbh, pbs);
		printf(_("should be (%d, %d, 1)\n"), pbc, !pbc);
	}
#endif

/* Ending on cylinder boundary? */
	if (peh != (heads - 1) || pes != sectors) {
		printf(_("Partition %i does not end on cylinder boundary.\n"),
			partition + 1);
#if 0
		printf(_("     phys=(%d, %d, %d) "), pec, peh, pes);
		printf(_("should be (%d, %d, %d)\n"),
		pec, heads - 1, sectors);
#endif
	}
}

static void
list_disk_geometry(void) {
	long long bytes = (total_number_of_sectors << 9);
	long megabytes = bytes/1000000;

	if (megabytes < 10000)
		printf(_("\nDisk %s: %ld MB, %lld bytes\n"),
		       disk_device, megabytes, bytes);
	else
		printf(_("\nDisk %s: %ld.%ld GB, %lld bytes\n"),
		       disk_device, megabytes/1000, (megabytes/100)%10, bytes);
	printf(_("%d heads, %d sectors/track, %d cylinders"),
	       heads, sectors, cylinders);
	if (units_per_sector == 1)
		printf(_(", total %llu sectors"),
		       total_number_of_sectors / (sector_size/512));
	printf("\n");
	printf(_("Units = %s of %d * %d = %d bytes\n\n"),
	       str_units(PLURAL),
	       units_per_sector, sector_size, units_per_sector * sector_size);
}

/*
 * Check whether partition entries are ordered by their starting positions.
 * Return 0 if OK. Return i if partition i should have been earlier.
 * Two separate checks: primary and logical partitions.
 */
static int
wrong_p_order(int *prev) {
	struct pte *pe;
	struct partition *p;
	unsigned int last_p_start_pos = 0, p_start_pos;
	int i, last_i = 0;

	for (i = 0 ; i < partitions; i++) {
		if (i == 4) {
			last_i = 4;
			last_p_start_pos = 0;
		}
		pe = &ptes[i];
		if ((p = pe->part_table)->sys_ind) {
			p_start_pos = get_partition_start(pe);

			if (last_p_start_pos > p_start_pos) {
				if (prev)
					*prev = last_i;
				return i;
			}

			last_p_start_pos = p_start_pos;
			last_i = i;
		}
	}
	return 0;
}

/*
 * Fix the chain of logicals.
 * extended_offset is unchanged, the set of sectors used is unchanged
 * The chain is sorted so that sectors increase, and so that
 * starting sectors increase.
 *
 * After this it may still be that cfdisk doesnt like the table.
 * (This is because cfdisk considers expanded parts, from link to
 * end of partition, and these may still overlap.)
 * Now
 *   sfdisk /dev/hda > ohda; sfdisk /dev/hda < ohda
 * may help.
 */
static void
fix_chain_of_logicals(void) {
	int j, oj, ojj, sj, sjj;
	struct partition *pj,*pjj,tmp;

	/* Stage 1: sort sectors but leave sector of part 4 */
	/* (Its sector is the global extended_offset.) */
 stage1:
	for (j = 5; j < partitions-1; j++) {
		oj = ptes[j].offset;