fdisk: move DOS new/add partition code

Since this is DOS specific logic, it belongs in its own label file.
Additionally, a dos_new_partition() function is created that asks the user for
partition type and then calls the actual dos_add_partition().

This patch passed fdisk regression tests, builds without problems and it was
locally tested against adding and removing DOS partitions.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>

1 files changed, 332 insertions, 0 deletions

diff --git a/fdisk/fdiskdoslabel.c b/fdisk/fdiskdoslabel.c
index 4dfe876dc..3f820dbf3 100644
--- a/fdisk/fdiskdoslabel.c
+++ b/fdisk/fdiskdoslabel.c
@@ -4,6 +4,7 @@
  */
 
 #include <unistd.h>
+#include <ctype.h>
 
 #include "nls.h"
 #include "xalloc.h"
@@ -12,10 +13,51 @@
 #include "fdisk.h"
 #include "fdiskdoslabel.h"
 
+#define set_hsc(h,s,c,sector) { \
+		s = sector % sectors + 1;			\
+		sector /= sectors;				\
+		h = sector % heads;				\
+		sector /= heads;				\
+		c = sector & 0xff;				\
+		s |= (sector >> 2) & 0xc0;			\
+	}
+
+#define alignment_required	(grain != sector_size)
+
 struct pte ptes[MAXIMUM_PARTS];
 unsigned long long extended_offset;
 int ext_index;
 
+static int get_nonexisting_partition(int warn, int max)
+{
+	int pno = -1;
+	int i;
+	int dflt = 0;
+
+	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) {
+				dflt = pno + 1;
+				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_dflt(warn, max, dflt);
+}
+
+
 /* Allocate a buffer and read a partition table sector */
 static void read_pte(int fd, int pno, unsigned long long offset)
 {
@@ -325,3 +367,293 @@ int is_dos_partition(int t)
 		t == 0x1b || t == 0x1c || t == 0x1e || t == 0x24 ||
 		t == 0xc1 || t == 0xc4 || t == 0xc6);
 }
+
+static void set_partition(int i, int doext, unsigned long long start,
+			  unsigned long long stop, int sysid)
+{
+	struct partition *p;
+	unsigned long long offset;
+
+	if (doext) {
+		p = ptes[i].ext_pointer;
+		offset = extended_offset;
+	} else {
+		p = ptes[i].part_table;
+		offset = ptes[i].offset;
+	}
+	p->boot_ind = 0;
+	p->sys_ind = sysid;
+	set_start_sect(p, start - offset);
+	set_nr_sects(p, stop - start + 1);
+
+	if (!doext)
+		print_partition_size(i + 1, start, stop, sysid);
+
+	if (dos_compatible_flag && (start/(sectors*heads) > 1023))
+		start = heads*sectors*1024 - 1;
+	set_hsc(p->head, p->sector, p->cyl, start);
+	if (dos_compatible_flag && (stop/(sectors*heads) > 1023))
+		stop = heads*sectors*1024 - 1;
+	set_hsc(p->end_head, p->end_sector, p->end_cyl, stop);
+	ptes[i].changed = 1;
+}
+
+static unsigned long long get_unused_start(int part_n,
+					   unsigned long long start,
+					   unsigned long long first[],
+					   unsigned long long last[])
+{
+	int i;
+
+	for (i = 0; i < partitions; i++) {
+		unsigned long long lastplusoff;
+
+		if (start == ptes[i].offset)
+			start += sector_offset;
+		lastplusoff = last[i] + ((part_n < 4) ? 0 : sector_offset);
+		if (start >= first[i] && start <= lastplusoff)
+			start = lastplusoff + 1;
+	}
+
+	return start;
+}
+
+static unsigned long long align_lba_in_range(	unsigned long long lba,
+						unsigned long long start,
+						unsigned long long stop)
+{
+	start = align_lba(start, ALIGN_UP);
+	stop = align_lba(stop, ALIGN_DOWN);
+
+	lba = align_lba(lba, ALIGN_NEAREST);
+
+	if (lba < start)
+		return start;
+	else if (lba > stop)
+		return stop;
+	return lba;
+}
+
+void dos_add_partition(int n, int sys)
+{
+	char mesg[256];		/* 48 does not suffice in Japanese */
+	int i, read = 0;
+	struct partition *p = ptes[n].part_table;
+	struct partition *q = ptes[ext_index].part_table;
+	unsigned long long start, stop = 0, limit, temp,
+		first[partitions], last[partitions];
+
+	if (p && p->sys_ind) {
+		printf(_("Partition %d is already defined.  Delete "
+			 "it before re-adding it.\n"), n + 1);
+		return;
+	}
+	fill_bounds(first, last);
+	if (n < 4) {
+		start = sector_offset;
+		if (display_in_cyl_units || !total_number_of_sectors)
+			limit = heads * sectors * cylinders - 1;
+		else
+			limit = total_number_of_sectors - 1;
+
+		if (limit > UINT_MAX)
+			limit = UINT_MAX;
+
+		if (extended_offset) {
+			first[ext_index] = extended_offset;
+			last[ext_index] = get_start_sect(q) +
+				get_nr_sects(q) - 1;
+		}
+	} else {
+		start = extended_offset + sector_offset;
+		limit = get_start_sect(q) + get_nr_sects(q) - 1;
+	}
+	if (display_in_cyl_units)
+		for (i = 0; i < partitions; i++)
+			first[i] = (cround(first[i]) - 1) * units_per_sector;
+
+	snprintf(mesg, sizeof(mesg), _("First %s"), str_units(SINGULAR));
+	do {
+		unsigned long long dflt, aligned;
+
+		temp = start;
+		dflt = start = get_unused_start(n, start, first, last);
+
+		/* the default sector should be aligned and unused */
+		do {
+			aligned = align_lba_in_range(dflt, dflt, limit);
+			dflt = get_unused_start(n, aligned, first, last);
+		} while (dflt != aligned && dflt > aligned && dflt < limit);
+
+		if (dflt >= limit)
+			dflt = start;
+		if (start > limit)
+			break;
+		if (start >= temp+units_per_sector && read) {
+			printf(_("Sector %llu is already allocated\n"), temp);
+			temp = start;
+			read = 0;
+		}
+		if (!read && start == temp) {
+			unsigned long long i = start;
+
+			start = read_int(cround(i), cround(dflt), cround(limit),
+					 0, mesg);
+			if (display_in_cyl_units) {
+				start = (start - 1) * units_per_sector;
+				if (start < i) start = i;
+			}
+			read = 1;
+		}
+	} while (start != temp || !read);
+	if (n > 4) {			/* NOT for fifth partition */
+		struct pte *pe = &ptes[n];
+
+		pe->offset = start - sector_offset;
+		if (pe->offset == extended_offset) { /* must be corrected */
+			pe->offset++;
+			if (sector_offset == 1)
+				start++;
+		}
+	}
+
+	for (i = 0; i < partitions; i++) {
+		struct pte *pe = &ptes[i];
+
+		if (start < pe->offset && limit >= pe->offset)
+			limit = pe->offset - 1;
+		if (start < first[i] && limit >= first[i])
+			limit = first[i] - 1;
+	}
+	if (start > limit) {
+		printf(_("No free sectors available\n"));
+		if (n > 4)
+			partitions--;
+		return;
+	}
+	if (cround(start) == cround(limit)) {
+		stop = limit;
+	} else {
+		int is_suffix_used = 0;
+
+		snprintf(mesg, sizeof(mesg),
+			_("Last %1$s, +%2$s or +size{K,M,G}"),
+			 str_units(SINGULAR), str_units(PLURAL));
+
+		stop = read_int_with_suffix(cround(start), cround(limit), cround(limit),
+				cround(start), mesg, &is_suffix_used);
+		if (display_in_cyl_units) {
+			stop = stop * units_per_sector - 1;
+			if (stop >limit)
+				stop = limit;
+		}
+
+		if (is_suffix_used && alignment_required) {
+			/* the last sector has not been exactly requested (but
+			 * defined by +size{K,M,G} convention), so be smart
+			 * and align the end of the partition. The next
+			 * partition will start at phy.block boundary.
+			 */
+			stop = align_lba_in_range(stop, start, limit) - 1;
+			if (stop > limit)
+				stop = limit;
+		}
+	}
+
+	set_partition(n, 0, start, stop, sys);
+	if (n > 4)
+		set_partition(n - 1, 1, ptes[n].offset, stop, EXTENDED);
+
+	if (IS_EXTENDED (sys)) {
+		struct pte *pe4 = &ptes[4];
+		struct pte *pen = &ptes[n];
+
+		ext_index = n;
+		pen->ext_pointer = p;
+		pe4->offset = extended_offset = start;
+		pe4->sectorbuffer = xcalloc(1, sector_size);
+		pe4->part_table = pt_offset(pe4->sectorbuffer, 0);
+		pe4->ext_pointer = pe4->part_table + 1;
+		pe4->changed = 1;
+		partitions = 5;
+	}
+}
+
+static void add_logical(void)
+{
+	if (partitions > 5 || ptes[4].part_table->sys_ind) {
+		struct pte *pe = &ptes[partitions];
+
+		pe->sectorbuffer = xcalloc(1, sector_size);
+		pe->part_table = pt_offset(pe->sectorbuffer, 0);
+		pe->ext_pointer = pe->part_table + 1;
+		pe->offset = 0;
+		pe->changed = 1;
+		partitions++;
+	}
+	printf(_("Adding logical partition %d\n"), partitions);
+	dos_add_partition(partitions - 1, LINUX_NATIVE);
+}
+
+/*
+ * Ask the user for new partition type information (logical, extended).
+ * This function calls the actual partition adding logic - dos_add_partition.
+ */
+void dos_new_partition(void)
+{
+	int i, free_primary = 0;
+
+	for (i = 0; i < 4; i++)
+		free_primary += !ptes[i].part_table->sys_ind;
+
+	if (!free_primary && partitions >= MAXIMUM_PARTS) {
+		printf(_("The maximum number of partitions has been created\n"));
+		return;
+	}
+
+	if (!free_primary) {
+		if (extended_offset) {
+			printf(_("All primary partitions are in use\n"));
+			add_logical();
+		} else
+			printf(_("If you want to create more than four partitions, you must replace a\n"
+				 "primary partition with an extended partition first.\n"));
+	} else if (partitions >= MAXIMUM_PARTS) {
+		printf(_("All logical partitions are in use\n"));
+		printf(_("Adding a primary partition\n"));
+		dos_add_partition(get_partition(0, 4), LINUX_NATIVE);
+	} else {
+		char c, dflt, line[LINE_LENGTH];
+
+		dflt = (free_primary == 1 && !extended_offset) ? 'e' : 'p';
+		snprintf(line, sizeof(line),
+			 _("Partition type:\n"
+			   "   p   primary (%d primary, %d extended, %d free)\n"
+			   "%s\n"
+			   "Select (default %c): "),
+			 4 - (extended_offset ? 1 : 0) - free_primary, extended_offset ? 1 : 0, free_primary,
+			 extended_offset ? _("   l   logical (numbered from 5)") : _("   e   extended"),
+			 dflt);
+
+		c = tolower(read_chars(line));
+		if (c == '\n') {
+			c = dflt;
+			printf(_("Using default response %c\n"), c);
+		}
+		if (c == 'p') {
+			int i = get_nonexisting_partition(0, 4);
+			if (i >= 0)
+				dos_add_partition(i, LINUX_NATIVE);
+			return;
+		} else if (c == 'l' && extended_offset) {
+			add_logical();
+			return;
+		} else if (c == 'e' && !extended_offset) {
+			int i = get_nonexisting_partition(0, 4);
+			if (i >= 0)
+				dos_add_partition(i, EXTENDED);
+			return;
+		} else
+			printf(_("Invalid partition type `%c'\n"), c);
+	}
+}