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|
/*
* gptsync/gptsync.c
* Platform-independent code for syncing GPT and MBR
*
* Copyright (c) 2006 Christoph Pfisterer
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* * Neither the name of Christoph Pfisterer nor the names of the
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "gptsync.h"
#include "syslinux_mbr.h"
// types
typedef struct {
UINT8 flags;
UINT8 start_chs[3];
UINT8 type;
UINT8 end_chs[3];
UINT32 start_lba;
UINT32 size;
} MBR_PARTITION_INFO;
typedef struct {
UINT8 type;
CHARN *name;
} MBR_PARTTYPE;
typedef struct {
UINT64 signature;
UINT32 spec_revision;
UINT32 header_size;
UINT32 header_crc32;
UINT32 reserved;
UINT64 header_lba;
UINT64 alternate_header_lba;
UINT64 first_usable_lba;
UINT64 last_usable_lba;
UINT8 disk_guid[16];
UINT64 entry_lba;
UINT32 entry_count;
UINT32 entry_size;
UINT32 entry_crc32;
} GPT_HEADER;
typedef struct {
UINT8 type_guid[16];
UINT8 partition_guid[16];
UINT64 start_lba;
UINT64 end_lba;
UINT64 attributes;
CHAR16 name[36];
} GPT_ENTRY;
#define GPT_KIND_SYSTEM (0)
#define GPT_KIND_DATA (1)
#define GPT_KIND_BASIC_DATA (2)
#define GPT_KIND_FATAL (3)
typedef struct {
UINT8 guid[16];
UINT8 mbr_type;
CHARN *name;
UINTN kind;
} GPT_PARTTYPE;
typedef struct {
UINTN index;
UINT64 start_lba;
UINT64 end_lba;
UINTN mbr_type;
UINT8 gpt_type[16];
GPT_PARTTYPE *gpt_parttype;
BOOLEAN active;
} PARTITION_INFO;
// variables
UINT8 empty_guid[16] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 };
PARTITION_INFO mbr_parts[4];
UINTN mbr_part_count = 0;
PARTITION_INFO gpt_parts[128];
UINTN gpt_part_count = 0;
PARTITION_INFO new_mbr_parts[4];
UINTN new_mbr_part_count = 0;
UINT8 sector[512];
MBR_PARTTYPE mbr_types[] = {
{ 0x01, STR("FAT12") },
{ 0x04, STR("FAT16 <32M") },
{ 0x05, STR("DOS Extended") },
{ 0x06, STR("FAT16") },
{ 0x07, STR("NTFS") },
{ 0x0b, STR("FAT32") },
{ 0x0c, STR("FAT32 (LBA)") },
{ 0x0e, STR("FAT16 (LBA)") },
{ 0x0f, STR("Win95 Extended (LBA)") },
{ 0x11, STR("Hidden FAT12") },
{ 0x14, STR("Hidden FAT16 <32M") },
{ 0x16, STR("Hidden FAT16") },
{ 0x17, STR("Hidden NTFS") },
{ 0x1b, STR("Hidden FAT32") },
{ 0x1c, STR("Hidden FAT32 (LBA)") },
{ 0x1e, STR("Hidden FAT16 (LBA)") },
{ 0x82, STR("Linux swap / Solaris") },
{ 0x83, STR("Linux") },
{ 0x85, STR("Linux Extended") },
{ 0x86, STR("NTFS volume set") },
{ 0x87, STR("NTFS volume set") },
{ 0x8e, STR("Linux LVM") },
{ 0xa5, STR("FreeBSD") },
{ 0xa6, STR("OpenBSD") },
{ 0xa7, STR("NeXTSTEP") },
{ 0xa9, STR("NetBSD") },
{ 0xaf, STR("Mac OS X HFS+") },
{ 0xeb, STR("BeOS") },
{ 0xee, STR("EFI Protective") },
{ 0xef, STR("EFI System (FAT)") },
{ 0xfd, STR("Linux RAID") },
{ 0, NULL },
};
GPT_PARTTYPE gpt_types[] = {
{ "\x28\x73\x2A\xC1\x1F\xF8\xD2\x11\xBA\x4B\x00\xA0\xC9\x3E\xC9\x3B", 0xef, STR("EFI System (FAT)"), GPT_KIND_SYSTEM },
{ "\x41\xEE\x4D\x02\xE7\x33\xD3\x11\x9D\x69\x00\x08\xC7\x81\xF3\x9F", 0x00, STR("MBR partition scheme"), GPT_KIND_FATAL },
{ "\x16\xE3\xC9\xE3\x5C\x0B\xB8\x4D\x81\x7D\xF9\x2D\xF0\x02\x15\xAE", 0x00, STR("MS Reserved"), GPT_KIND_SYSTEM },
{ "\xA2\xA0\xD0\xEB\xE5\xB9\x33\x44\x87\xC0\x68\xB6\xB7\x26\x99\xC7", 0x00, STR("Basic Data"), GPT_KIND_BASIC_DATA },
{ "\xAA\xC8\x08\x58\x8F\x7E\xE0\x42\x85\xD2\xE1\xE9\x04\x34\xCF\xB3", 0x00, STR("MS LDM Metadata"), GPT_KIND_FATAL },
{ "\xA0\x60\x9B\xAF\x31\x14\x62\x4F\xBC\x68\x33\x11\x71\x4A\x69\xAD", 0x00, STR("MS LDM Data"), GPT_KIND_FATAL },
{ "\x0F\x88\x9D\xA1\xFC\x05\x3B\x4D\xA0\x06\x74\x3F\x0F\x84\x91\x1E", 0xfd, STR("Linux RAID"), GPT_KIND_DATA },
{ "\x6D\xFD\x57\x06\xAB\xA4\xC4\x43\x84\xE5\x09\x33\xC8\x4B\x4F\x4F", 0x82, STR("Linux Swap"), GPT_KIND_DATA },
{ "\x79\xD3\xD6\xE6\x07\xF5\xC2\x44\xA2\x3C\x23\x8F\x2A\x3D\xF9\x28", 0x8e, STR("Linux LVM"), GPT_KIND_DATA },
{ "\x39\x33\xA6\x8D\x07\x00\xC0\x60\xC4\x36\x08\x3A\xC8\x23\x09\x08", 0x00, STR("Linux Reserved"), GPT_KIND_SYSTEM },
{ "\x00\x53\x46\x48\x00\x00\xAA\x11\xAA\x11\x00\x30\x65\x43\xEC\xAC", 0xaf, STR("Mac OS X HFS+"), GPT_KIND_DATA },
{ { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }, 0, NULL, 0 },
};
GPT_PARTTYPE gpt_dummy_type =
{ { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }, 0, STR("Unknown"), GPT_KIND_FATAL };
//
// MBR functions
//
static CHARN * mbr_parttype_name(UINT8 type)
{
int i;
for (i = 0; mbr_types[i].name; i++)
if (mbr_types[i].type == type)
return mbr_types[i].name;
return STR("Unknown");
}
static UINTN read_mbr(VOID)
{
UINTN status;
UINTN i;
BOOLEAN used;
MBR_PARTITION_INFO *table;
Print(L"\nCurrent MBR partition table:\n");
// read MBR data
status = read_sector(0, sector);
if (status != 0)
return status;
// check for validity
if (*((UINT16 *)(sector + 510)) != 0xaa55) {
Print(L" No MBR partition table present!\n");
return 1;
}
table = (MBR_PARTITION_INFO *)(sector + 446);
for (i = 0; i < 4; i++) {
if (table[i].flags != 0x00 && table[i].flags != 0x80) {
Print(L" MBR partition table is invalid!\n");
return 1;
}
}
// check if used
used = FALSE;
for (i = 0; i < 4; i++) {
if (table[i].start_lba > 0 && table[i].size > 0) {
used = TRUE;
break;
}
}
if (!used) {
Print(L" No partitions defined\n");
return 0;
}
// dump current state & fill internal structures
Print(L" # A Start LBA End LBA Type\n");
for (i = 0; i < 4; i++) {
if (table[i].start_lba == 0 || table[i].size == 0)
continue;
mbr_parts[mbr_part_count].index = i;
mbr_parts[mbr_part_count].start_lba = (UINT64)table[i].start_lba;
mbr_parts[mbr_part_count].end_lba = (UINT64)table[i].start_lba + (UINT64)table[i].size - 1;
mbr_parts[mbr_part_count].mbr_type = table[i].type;
mbr_parts[mbr_part_count].active = (table[i].flags == 0x80) ? TRUE : FALSE;
Print(L" %d %s %12lld %12lld %02x %s\n",
mbr_parts[mbr_part_count].index + 1,
mbr_parts[mbr_part_count].active ? STR("*") : STR(" "),
mbr_parts[mbr_part_count].start_lba,
mbr_parts[mbr_part_count].end_lba,
mbr_parts[mbr_part_count].mbr_type,
mbr_parttype_name(mbr_parts[mbr_part_count].mbr_type));
mbr_part_count++;
}
return 0;
}
static UINTN check_mbr(VOID)
{
UINTN i, k;
// check each entry
for (i = 0; i < mbr_part_count; i++) {
// check for overlap
for (k = 0; k < mbr_part_count; k++) {
if (k != i && !(mbr_parts[i].start_lba > mbr_parts[k].end_lba || mbr_parts[k].start_lba > mbr_parts[i].end_lba)) {
Print(L"Status: MBR partition table is invalid, partitions overlap.\n");
return 1;
}
}
// check for extended partitions
if (mbr_parts[i].mbr_type == 0x05 || mbr_parts[i].mbr_type == 0x0f || mbr_parts[i].mbr_type == 0x85) {
Print(L"Status: Extended partition found in MBR table, will not touch this disk.\n",
gpt_parts[i].gpt_parttype->name);
return 1;
}
}
return 0;
}
static UINTN write_mbr(VOID)
{
UINTN status;
UINTN i, k;
UINT8 active;
UINT64 lba;
MBR_PARTITION_INFO *table;
BOOLEAN have_bootcode;
Print(L"\nWriting new MBR...\n");
// read MBR data
status = read_sector(0, sector);
if (status != 0)
return status;
// write partition table
*((UINT16 *)(sector + 510)) = 0xaa55;
table = (MBR_PARTITION_INFO *)(sector + 446);
active = 0x80;
for (i = 0; i < 4; i++) {
for (k = 0; k < new_mbr_part_count; k++) {
if (new_mbr_parts[k].index == i)
break;
}
if (k >= new_mbr_part_count) {
// unused entry
table[i].flags = 0;
table[i].start_chs[0] = 0;
table[i].start_chs[1] = 0;
table[i].start_chs[2] = 0;
table[i].type = 0;
table[i].end_chs[0] = 0;
table[i].end_chs[1] = 0;
table[i].end_chs[2] = 0;
table[i].start_lba = 0;
table[i].size = 0;
} else {
if (new_mbr_parts[k].active) {
table[i].flags = active;
active = 0x00;
} else
table[i].flags = 0x00;
table[i].start_chs[0] = 0xfe;
table[i].start_chs[1] = 0xff;
table[i].start_chs[2] = 0xff;
table[i].type = new_mbr_parts[k].mbr_type;
table[i].end_chs[0] = 0xfe;
table[i].end_chs[1] = 0xff;
table[i].end_chs[2] = 0xff;
lba = new_mbr_parts[k].start_lba;
if (lba > 0xffffffffULL) {
Print(L"Warning: Partition %d starts beyond 2 TiB limit\n", i+1);
lba = 0xffffffffULL;
}
table[i].start_lba = (UINT32)lba;
lba = new_mbr_parts[k].end_lba + 1 - new_mbr_parts[k].start_lba;
if (lba > 0xffffffffULL) {
Print(L"Warning: Partition %d extends beyond 2 TiB limit\n", i+1);
lba = 0xffffffffULL;
}
table[i].size = (UINT32)lba;
}
}
// add boot code if necessary
have_bootcode = FALSE;
for (i = 0; i < MBR_BOOTCODE_SIZE; i++) {
if (sector[i] != 0) {
have_bootcode = TRUE;
break;
}
}
if (!have_bootcode) {
// no boot code found in the MBR, add the syslinux MBR code
SetMem(sector, MBR_BOOTCODE_SIZE, 0);
CopyMem(sector, syslinux_mbr, SYSLINUX_MBR_SIZE);
}
// write MBR data
status = write_sector(0, sector);
if (status != 0)
return status;
Print(L"MBR updated successfully!\n");
return 0;
}
//
// GPT functions
//
static GPT_PARTTYPE * gpt_parttype(UINT8 *type_guid)
{
int i;
for (i = 0; gpt_types[i].name; i++)
if (guids_are_equal(gpt_types[i].guid, type_guid))
return &(gpt_types[i]);
return &gpt_dummy_type;
}
static UINTN read_gpt(VOID)
{
UINTN status;
GPT_HEADER *header;
GPT_ENTRY *entry;
UINT64 entry_lba;
UINTN entry_count, entry_size, i;
Print(L"\nCurrent GPT partition table:\n");
// read GPT header
status = read_sector(1, sector);
if (status != 0)
return status;
// check signature
header = (GPT_HEADER *)sector;
if (header->signature != 0x5452415020494645ULL) {
Print(L" No GPT partition table present!\n");
return 0;
}
if (header->spec_revision != 0x00010000UL) {
Print(L" Warning: Unknown GPT spec revision 0x%08x\n", header->spec_revision);
}
if ((512 % header->entry_size) > 0 || header->entry_size > 512) {
Print(L" Error: Invalid GPT entry size (misaligned or more than 512 bytes)\n");
return 0;
}
// read entries
entry_lba = header->entry_lba;
entry_size = header->entry_size;
entry_count = header->entry_count;
Print(L" # Start LBA End LBA Type\n");
for (i = 0; i < entry_count; i++) {
if (((i * entry_size) % 512) == 0) {
status = read_sector(entry_lba, sector);
if (status != 0)
return status;
entry_lba++;
}
entry = (GPT_ENTRY *)(sector + ((i * entry_size) % 512));
if (guids_are_equal(entry->type_guid, empty_guid))
continue;
gpt_parts[gpt_part_count].index = i;
gpt_parts[gpt_part_count].start_lba = entry->start_lba;
gpt_parts[gpt_part_count].end_lba = entry->end_lba;
gpt_parts[gpt_part_count].mbr_type = 0;
copy_guid(gpt_parts[gpt_part_count].gpt_type, entry->type_guid);
gpt_parts[gpt_part_count].gpt_parttype = gpt_parttype(gpt_parts[gpt_part_count].gpt_type);
gpt_parts[gpt_part_count].active = FALSE;
Print(L" %d %12lld %12lld %s\n",
gpt_parts[gpt_part_count].index + 1,
gpt_parts[gpt_part_count].start_lba,
gpt_parts[gpt_part_count].end_lba,
gpt_parts[gpt_part_count].gpt_parttype->name);
gpt_part_count++;
}
return 0;
}
static UINTN check_gpt(VOID)
{
UINTN i, k;
BOOLEAN found_data_parts;
if (gpt_part_count == 0) {
Print(L"Status: No GPT partition table, no need to sync.\n");
return 1;
}
// check each entry
found_data_parts = FALSE;
for (i = 0; i < gpt_part_count; i++) {
// check sanity
if (gpt_parts[i].end_lba < gpt_parts[i].start_lba) {
Print(L"Status: GPT partition table is invalid.\n");
return 1;
}
// check for overlap
for (k = 0; k < gpt_part_count; k++) {
if (k != i && !(gpt_parts[i].start_lba > gpt_parts[k].end_lba || gpt_parts[k].start_lba > gpt_parts[i].end_lba)) {
Print(L"Status: GPT partition table is invalid, partitions overlap.\n");
return 1;
}
}
// check for partitions kind
if (gpt_parts[i].gpt_parttype->kind == GPT_KIND_FATAL) {
Print(L"Status: GPT partition of type '%s' found, will not touch this disk.\n",
gpt_parts[i].gpt_parttype->name);
return 1;
}
if (gpt_parts[i].gpt_parttype->kind == GPT_KIND_DATA ||
gpt_parts[i].gpt_parttype->kind == GPT_KIND_BASIC_DATA)
found_data_parts = TRUE;
}
if (!found_data_parts) {
Print(L"Status: GPT partition table has no data partitions, no need to sync.\n");
return 1;
}
return 0;
}
//
// compare GPT and MBR tables
//
#define ACTION_NONE (0)
#define ACTION_NOP (1)
#define ACTION_REWRITE (2)
static UINTN analyze(VOID)
{
UINTN action = ACTION_NONE;
UINTN i, k, iter;
UINT64 min_start_lba;
BOOLEAN have_active;
new_mbr_part_count = 0;
// check for common scenarios
if (mbr_part_count == 0) {
// current MBR is empty
action = ACTION_REWRITE;
} else if (mbr_part_count == 1 && mbr_parts[0].mbr_type == 0xee) {
// MBR has just the EFI Protective partition (i.e. untouched)
action = ACTION_REWRITE;
}
if (action == ACTION_NONE && mbr_part_count > 0) {
if (mbr_parts[0].mbr_type == 0xee &&
gpt_parts[0].gpt_parttype->mbr_type == 0xef &&
mbr_parts[0].start_lba == 1 &&
mbr_parts[0].end_lba == gpt_parts[0].end_lba) {
// The Apple Way, "EFI Protective" covering the tables and the ESP
action = ACTION_NOP;
if ((mbr_part_count != gpt_part_count && gpt_part_count <= 4) ||
(mbr_part_count != 4 && gpt_part_count > 4)) {
// number of partitions has changed
action = ACTION_REWRITE;
} else {
// check partition ranges and types
for (i = 1; i < mbr_part_count; i++) {
if (mbr_parts[i].start_lba != gpt_parts[i].start_lba ||
mbr_parts[i].end_lba != gpt_parts[i].end_lba ||
(gpt_parts[i].gpt_parttype->mbr_type && mbr_parts[i].mbr_type != gpt_parts[i].gpt_parttype->mbr_type))
// position or type has changed
action = ACTION_REWRITE;
}
}
}
}
if (action == ACTION_NONE && mbr_part_count > 0 && mbr_parts[0].mbr_type == 0xef) {
// The XOM Way, all partitions mirrored 1:1
action = ACTION_REWRITE;
// check partition ranges and types
for (i = 0; i < mbr_part_count; i++) {
if (mbr_parts[i].start_lba != gpt_parts[i].start_lba ||
mbr_parts[i].end_lba != gpt_parts[i].end_lba ||
(gpt_parts[i].gpt_parttype->mbr_type && mbr_parts[i].mbr_type != gpt_parts[i].gpt_parttype->mbr_type))
// position or type has changed -> better don't touch
action = ACTION_NONE;
}
}
if (action == ACTION_NOP) {
Print(L"Status: Tables are synchronized, no need to sync.\n");
return 0;
} else if (action == ACTION_REWRITE) {
Print(L"Status: MBR table must be updated.\n");
} else {
Print(L"Status: Analysis inconclusive, will not touch this disk.\n");
return 1;
}
// generate the new table
// first entry: EFI Protective
new_mbr_parts[0].index = 0;
new_mbr_parts[0].start_lba = 1;
new_mbr_parts[0].mbr_type = 0xee;
new_mbr_part_count = 1;
if (gpt_parts[0].gpt_parttype->mbr_type == 0xef) {
new_mbr_parts[0].end_lba = gpt_parts[0].end_lba;
i = 1;
} else {
min_start_lba = gpt_parts[0].start_lba;
for (k = 0; k < gpt_part_count; k++) {
if (min_start_lba > gpt_parts[k].start_lba)
min_start_lba = gpt_parts[k].start_lba;
}
new_mbr_parts[0].end_lba = min_start_lba - 1;
i = 0;
}
// add other GPT partitions until the table is full
for (; i < gpt_part_count && new_mbr_part_count < 4; i++) {
new_mbr_parts[new_mbr_part_count].index = new_mbr_part_count;
new_mbr_parts[new_mbr_part_count].start_lba = gpt_parts[i].start_lba;
new_mbr_parts[new_mbr_part_count].end_lba = gpt_parts[i].end_lba;
new_mbr_parts[new_mbr_part_count].mbr_type = gpt_parts[i].gpt_parttype->mbr_type;
new_mbr_parts[new_mbr_part_count].active = FALSE;
// find matching partition in the old MBR table
for (k = 0; k < mbr_part_count; k++) {
if (mbr_parts[k].start_lba == gpt_parts[i].start_lba) {
if (new_mbr_parts[new_mbr_part_count].mbr_type == 0)
new_mbr_parts[new_mbr_part_count].mbr_type = mbr_parts[k].mbr_type;
new_mbr_parts[new_mbr_part_count].active = mbr_parts[k].active;
break;
}
}
if (new_mbr_parts[new_mbr_part_count].mbr_type == 0) {
// TODO: detect the actual file system on the partition
// fallback: use linux native
//if (gpt_parts[i].gpt_parttype->kind == GPT_KIND_BASIC_DATA) {
new_mbr_parts[new_mbr_part_count].mbr_type = 0x83;
}
new_mbr_part_count++;
}
// if no partition is active, pick one
for (iter = 0; iter < 3; iter++) {
// check
have_active = FALSE;
for (i = 0; i < new_mbr_part_count; i++)
if (new_mbr_parts[i].active)
have_active = TRUE;
if (have_active)
break;
// set active on the first matching partition
for (i = 0; i < new_mbr_part_count; i++) {
if ((iter >= 0 && (new_mbr_parts[i].mbr_type == 0x07 ||
new_mbr_parts[i].mbr_type == 0x0b ||
new_mbr_parts[i].mbr_type == 0x0c)) ||
(iter >= 1 && (new_mbr_parts[i].mbr_type == 0x83)) ||
(iter >= 2 && i > 0)) {
new_mbr_parts[i].active = TRUE;
break;
}
}
}
// dump table
Print(L"\nProposed new MBR partition table:\n");
Print(L" # A Start LBA End LBA Type\n");
for (i = 0; i < new_mbr_part_count; i++) {
Print(L" %d %s %12lld %12lld %02x %s\n",
new_mbr_parts[i].index + 1,
new_mbr_parts[i].active ? STR("*") : STR(" "),
new_mbr_parts[i].start_lba,
new_mbr_parts[i].end_lba,
new_mbr_parts[i].mbr_type,
mbr_parttype_name(new_mbr_parts[i].mbr_type));
}
return 0;
}
//
// sync algorithm entry point
//
UINTN gptsync(VOID)
{
UINTN status = 0;
UINTN status_gpt, status_mbr;
// BOOLEAN proceed = FALSE;
// get full information from disk
status_gpt = read_gpt();
status_mbr = read_mbr();
if (status_gpt != 0 || status_mbr != 0)
return (status_gpt || status_mbr);
// cross-check current situation
Print(L"\n");
status = check_gpt(); // check GPT for consistency
if (status != 0)
return status;
status = check_mbr(); // check MBR for consistency
if (status != 0)
return status;
status = analyze(); // analyze the situation
if (status != 0)
return status;
if (new_mbr_part_count == 0)
return status;
// offer user the choice what to do
// status = input_boolean(STR("\nMay I update the MBR as printed above? [y/N] "), &proceed);
// if (status != 0 || proceed != TRUE)
// return status;
// adjust the MBR and write it back
status = write_mbr();
if (status != 0)
return status;
return status;
}
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