aboutsummaryrefslogtreecommitdiff
path: root/toys/pending/fdisk.c
blob: 4cc0190ad91a3de23c96e2c9c56ea78064679f51 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
/* fdisk.c -  fdisk program to modify partitions on disk.
 *
 * Copyright 2012 Ashwini Kumar <ak.ashwini@gmail.com>
 * Copyright 2013 Kyungwan Han <asura321@gmail.com>
 *
 * No Standard.

USE_FDISK(NEWTOY(fdisk, "C#<0H#<0S#<0b#<512ul", TOYFLAG_SBIN))

config FDISK
  bool "fdisk"
  default n
  help
    usage: fdisk [-lu] [-C CYLINDERS] [-H HEADS] [-S SECTORS] [-b SECTSZ] DISK

    Change partition table

    -u            Start and End are in sectors (instead of cylinders)
    -l            Show partition table for each DISK, then exit
    -b size       sector size (512, 1024, 2048 or 4096)
    -C CYLINDERS  Set number of cylinders/heads/sectors
    -H HEADS
    -S SECTORS
*/

#define FOR_fdisk
#include "toys.h"
#include <linux/hdreg.h>

GLOBALS(
  long sect_sz;
  long sectors;
  long heads;
  long cylinders;
)

#define EXTENDED        0x05                                                                      
#define WIN98_EXTENDED  0x0f
#define LINUX_NATIVE    0x83
#define LINUX_EXTENDED  0x85

#define SECTOR_SIZE 512
#define ONE_K       1024
#define PARTITION_MAX  60  //partition max is modifiable
#define IS_EXTENDED(i) ((i) == EXTENDED || (i) == WIN98_EXTENDED || (i) == LINUX_EXTENDED)
#define sector(s) ((s) & 0x3f)
#define cylinder(s, c) ((c) | (((s) & 0xc0) << 2))

typedef unsigned long long sector_t;

struct partition {
  unsigned char boot_ind, head, sector, cyl, sys_ind, end_head,
                end_sector, end_cyl, start4[4], size4[4];
};

struct part_entry {
  struct partition *part;
  char *sec_buffer;
  sector_t  start_offset;
  int modified;
};

struct part_types {
  int id;
  char type[24];
} sys_types[] = {
  {0x00, "Empty"}, {0x01, "FAT12"}, {0x04, "FAT16 <32M"}, {0x05, "Extended"},
  {0x06, "FAT16"}, {0x07, "HPFS/NTFS"}, {0x0a, "OS/2 Boot Manager"},
  {0x0b, "Win95 FAT32"}, {0x0c, "Win95 FAT32 (LBA)"}, {0x0e, "Win95 FAT16 (LBA)"},
  {0x0f, "Win95 Ext'd (LBA)"}, {0x11, "Hidden FAT12"}, {0x12, "Compaq diagnostics"},
  {0x14, "Hidden FAT16 <32M"}, {0x16, "Hidden FAT16"}, {0x17, "Hidden HPFS/NTFS"},
  {0x1b, "Hidden Win95 FAT32"}, {0x1c, "Hidden W95 FAT32 (LBA)"}, {0x1e, "Hidden W95 FAT16 (LBA)"},
  {0x3c, "Part.Magic recovery"}, {0x41, "PPC PReP Boot"}, {0x42, "SFS"},
  {0x63, "GNU HURD or SysV"}, {0x80, "Old Minix"}, {0x81, "Minix / old Linux"},
  {0x82, "Linux swap"}, {0x83, "Linux"}, {0x84, "OS/2 hidden C: drive"},
  {0x85, "Linux extended"}, {0x86, "NTFS volume set"}, {0x87, "NTFS volume set"},
  {0x8e, "Linux LVM"}, {0x9f, "BSD/OS"}, {0xa0, "Thinkpad hibernation"},
  {0xa5, "FreeBSD"}, {0xa6, "OpenBSD"}, {0xa8, "Darwin UFS"}, {0xa9, "NetBSD"},
  {0xab, "Darwin boot"}, {0xb7, "BSDI fs"}, {0xb8, "BSDI swap"},
  {0xbe, "Solaris boot"}, {0xeb, "BeOS fs"}, {0xee, "EFI GPT"},
  {0xef, "EFI (FAT-12/16/32)"}, {0xf0, "Linux/PA-RISC boot"},
  {0xf2, "DOS secondary"}, {0xfd, "Linux raid autodetect"},
};

static int num_parts, disp_unit_cyl, dos_flag, dev_fd = 3;
static long g_cylinders, g_heads, g_sectors, g_sect_size;
static sector_t total_number_sectors, extended_offset;
static char MBRbuf[2048], *disk_device;
struct part_entry partitions[PARTITION_MAX];

static struct partition* part_offset(char *secbuf, int i)
{
  return (struct partition*)(secbuf + 0x1be + i*(sizeof(struct partition)));
}

static void set_levalue(unsigned char *cp, sector_t value )
{
  uint32_t val = SWAP_LE32(value);
  memcpy(cp, (void*)&val, 4);
}

static void set_hsc(struct partition *p, sector_t start, sector_t end)
{
  if (dos_flag && (start / (g_sectors * g_heads) > 1023))
    start = g_heads * g_sectors * ONE_K - 1;
  p->sector = (start % g_sectors) + 1;
  start /= g_sectors;
  p->head = start % g_heads;
  start /= g_heads;
  p->cyl = start & 0xFF;
  p->sector |= (start >> 2) & 0xc0;

  if (dos_flag && (end / (g_sectors * g_heads) > 1023))
    end = g_heads * g_sectors * ONE_K - 1;
  p->end_sector = (end % g_sectors) + 1;
  end /= g_sectors;
  p->end_head = end % g_heads;
  end /= g_heads;
  p->end_cyl = end & 0xFF;
  p->end_sector |= (end >> 2) & 0xc0;
}

static int chs_warn(void)
{
  if (g_heads && g_sectors && g_cylinders)
    return 0;

  printf("Unknown value(s) for:");
  if (!g_heads) printf(" heads");
  if (!g_sectors) printf(" sectors");
  if (!g_cylinders) printf(" cylinders");
  printf(". can set in the expert menu.\n");
  return 1;
}

static void list_types(void)
{
  int i, adjust = 0, size = ARRAY_LEN(sys_types);
 
  if(size % 2) adjust = 1;
  for (i = 0; i < (size - adjust); i+=2)
    xprintf("%2x %-22s\t\t%2x %-22.22s\n", sys_types[i].id, sys_types[i].type,
        sys_types[i+1].id, sys_types[i+1].type);
  if (adjust) xprintf("%2x %-22s\n",sys_types[size-1].id, sys_types[size-1].type);
  xputc('\n');
}

static void read_sec_sz()
{
  int arg;       
  if (ioctl(dev_fd, BLKSSZGET, &arg) == 0) g_sect_size = arg;
  if (toys.optflags & FLAG_b) {
    if (TT.sect_sz !=  512 && TT.sect_sz != 1024 && TT.sect_sz != 2048 &&
        TT.sect_sz != 4096)
    {
      help_exit("bad sector size");
    }
    g_sect_size = TT.sect_sz;
  }
}

static sector_t read_size()
{
  uint64_t sec64 = 0;
  unsigned long sectors = 0;
  if (ioctl(dev_fd, BLKGETSIZE64, &sec64) == 0) {
    sec64 = sec64 >> 9; //convert to 512 block size.
    if (sec64 != (uint32_t) sec64) {
      perror_msg("device has more than 2^32 sectors, can't use all of them");
      sec64 = (uint32_t) - 1L;
    }
    return sec64;
  }
  if (ioctl(dev_fd, BLKGETSIZE, &sectors) == 0)
    if (sizeof(long) > sizeof(sector_t) && sectors != (sector_t)sectors)
      sectors = (uint32_t) - 1L;
  return sectors;
}

static int validate_part_buff(char *buffer)
{
  if ((buffer[510] != 0x55) || (buffer[511] != 0xAA)) return 0;
  return 1;
}

static int is_partition_clear(struct partition* p)
{
  int i = 0;
  unsigned char res = 0;
  const char *ptr = (const char*)p;

  for (i = 0; i < sizeof(struct partition); i++) res |= (unsigned char)ptr[i];
  return (res == 0x00);
}

static uint32_t swap_le32toh(unsigned char *cp)
{
  uint32_t val;
  memcpy((void*)&val, cp, 4);
  return le32toh(val);
}

static int check_order(void)    
{                              
  sector_t first[num_parts], last_seen_val = 0;
  int i;
  struct part_entry *pe;       
  struct partition *px;

  for (i = 0; i < num_parts; i++) {
    if (i == 4) last_seen_val = 0;
    pe = &partitions[i];       
    px = pe->part;             
    if (px->sys_ind) {
      first[i] = swap_le32toh(px->start4) + pe->start_offset;
      if (last_seen_val > first[i]) return 1;
      last_seen_val = first[i];
    }
  }
  return 0;
}

static void read_geometry(struct hd_geometry *disk)
{
  struct hd_geometry geometry;

  if (ioctl(dev_fd, HDIO_GETGEO, &geometry)) return;
  disk->heads = geometry.heads;
  disk->sectors = geometry.sectors;
}

/* Read the extended boot record for the 
 * logical partion details.
 */
static void read_ebr(int idx)
{
  char *sec_buf = NULL;
  sector_t offset = 0, local_start_off = 0;
  struct partition *p, *q;

  q = p = partitions[idx].part;
  local_start_off = swap_le32toh(p->start4);

  if (!extended_offset) extended_offset = local_start_off;
  do {
    if (num_parts >= 60) {
      xprintf("Warning: deleting partitions after 60\n");
      memset(q, 0, sizeof(struct partition)); //clear_partition
      partitions[num_parts-1].modified = 1;
      break;
    }

    sec_buf = xzalloc(g_sect_size);
    partitions[num_parts].part = part_offset(sec_buf, 0);
    partitions[num_parts].sec_buffer = sec_buf;
    offset = swap_le32toh(q->start4);

    if (num_parts > 4) offset += local_start_off;
    partitions[num_parts].start_offset = offset;
    xlseek(dev_fd, (off_t)(offset * g_sect_size), SEEK_SET);

    if (g_sect_size != readall(dev_fd, sec_buf, g_sect_size)) {
      close(dev_fd);
      error_exit("Couldn't read sector zero\n");
    }
    num_parts++; //extended partions present.
    q = part_offset(sec_buf, 1);
  } while (!is_partition_clear(q) && IS_EXTENDED(q->sys_ind));
}

static void physical_HS(int* h, int *s)
{  
  struct partition *p;
  int i, end_h, end_s, e_hh = 0, e_ss = 0, ini = 1, dirty = 0;
  const unsigned char *bufp = (const unsigned char *)MBRbuf;

  if (!(validate_part_buff((char*)bufp))) return;

  for (i = 0; i < 4; i++) {
    p = part_offset((char*)bufp, i);
    if (p->sys_ind) {
      end_h = p->end_head + 1;
      end_s = (p->end_sector & 077);
      if (ini) {
        e_hh = end_h;
        e_ss = end_s;
        ini = 0;
      } else if (e_hh !=end_h || e_ss != end_s)
        dirty = 1;
    }
  }
  if (!dirty && !ini) {
    *h = e_hh;
    *s = e_ss;
  }
}

//Reset the primary partition table
static void reset_boot(int change)
{
  int i;
  for(i = 0; i < 4; i++) {
    struct part_entry *pe = &partitions[i];
    pe->part = part_offset(MBRbuf, i);
    pe->start_offset = 0;
    pe->sec_buffer = MBRbuf;
    pe->modified = change;
  }
}

static inline void write_table_flag(char *buf)
{
  buf[510] = 0x55;
  buf[511] = 0xaa;
}

/* free the buffers used for holding details of
 * extended logical partions
*/
static void free_bufs(void)
{
  int i = 4;
  for (; i < num_parts; i++) free(partitions[i].sec_buffer);
}

static void create_empty_doslabel(void)
{
  xprintf("Building a new DOS Disklabel. The changes will\n"
      "remain in memory only, until you write it.\n");

  num_parts = 4;
  extended_offset = 0;
  memset(&MBRbuf[510 - 4*16], 0, 4*16);
  write_table_flag(MBRbuf);
  partitions[0].modified = 1;
  reset_boot(1);
}

/* Read the Master Boot sector of the device for the 
 * partition table entries/details.
 * If any extended partition is found then read the EBR
 * for logical partition details
 */
static int read_mbr(char *device, int validate)
{
  int fd, sector_fac, i, h = 0, s = 0;
  struct hd_geometry disk;
  fd = open(device, O_RDWR);
  if(fd < 0) {
    perror_msg("can't open '%s'",device);
    return 1;
  }

  disk_device = strdup(device);
  if(fd != dev_fd) {
    if(dup2(fd, dev_fd) != dev_fd) perror_exit("Can't dup2");
    close(fd);
  }

  //read partition table - MBR
  if (SECTOR_SIZE != readall(dev_fd, MBRbuf, SECTOR_SIZE)) {
    close(dev_fd);
    perror_exit("Couldn't read sector zero\n");
  }
  if (validate && !validate_part_buff(MBRbuf)) {
    xprintf("Device contains neither a valid DOS "
        "partition table, nor Sun, SGI, OSF or GPT "
        "disklabel\n");
    create_empty_doslabel();
  }

  disk.heads = disk.sectors = 0;
  read_geometry(&disk); //CHS values
  total_number_sectors = read_size(); //Device size
  read_sec_sz();
  sector_fac = g_sect_size/SECTOR_SIZE; //512 is hardware sector size.
  physical_HS(&h, &s); //physical dimensions may be diferent from HDIO_GETGEO
  g_sectors = (toys.optflags & FLAG_S && TT.sectors)? TT.sectors :  s? s : disk.sectors?disk.sectors : 63;
  g_heads = (toys.optflags & FLAG_H && TT.heads)? TT.heads : h? h : disk.heads? disk.heads : 255;
  g_cylinders = total_number_sectors/(g_heads * g_sectors * sector_fac);

  if (!g_cylinders) g_cylinders = toys.optflags & FLAG_C? TT.cylinders : 0;
  if ((g_cylinders > ONE_K) && !(toys.optflags & (FLAG_l | FLAG_S)))
    xprintf("\nThe number of cylinders for this disk is set to %lu.\n"
        "There is nothing wrong with that, but this is larger than 1024,\n"
        "and could in certain setups cause problems.\n", g_cylinders);
  for (i = 0; i < num_parts; i++) {
    if (IS_EXTENDED(partitions[i].part->sys_ind)) {
      read_ebr(i);
      break;
    }
  }
  chs_warn();

  return 0;
}

static char* get_type(int sys_ind)
{
  int i, size = ARRAY_LEN(sys_types);
  for (i = 0; i < size; i++)
    if (sys_ind == sys_types[i].id)
      return sys_types[i].type;
  return "Unknown";
}

static void consistency_check(const struct partition *p, int partition)
{        
  unsigned physbc, physbh, physbs, physec, physeh, physes;
  unsigned lbc, lbh, lbs, lec, leh, les;
  sector_t start, end;

  if (!g_heads || !g_sectors || (partition >= 4)) return;
  // physical beginning c, h, s 
  physbc = cylinder(p->sector,p->cyl);
  physbh = p->head;
  physbs = sector(p->sector);
  // physical ending c, h, s 
  physec = cylinder(p->end_sector, p->end_cyl);
  physeh = p->end_head;
  physes = sector(p->end_sector);
  // logical begin and end CHS values 
  start = swap_le32toh((unsigned char*)(p->start4));
  end = start + swap_le32toh((unsigned char*)(p->size4)) -1;

  lbc = start/(g_sectors * g_heads);
  lbh = (start/g_sectors) % g_heads;
  lbs = (start % g_sectors) + 1;

  lec = end/(g_sectors * g_heads);
  leh = (end/g_sectors) % g_heads;
  les = (end % g_sectors) + 1;

  //Logical and Physical diff 
  if (g_cylinders <= ONE_K && (physbc != lbc || physbh != lbh || physbs != lbs)) {
    xprintf("Partition %u has different physical/logical beginings (Non-Linux?): \n", partition+1);
    xprintf("phys = (%u %u %u) ",physbc, physbh, physbs);
    xprintf("logical = (%u %u %u)\n", lbc, lbh, lbs);
  }
  if (g_cylinders <= ONE_K && (physec != lec || physeh != leh || physes != les)) {
    xprintf("Partition %u has different physical/logical endings: \n", partition+1);
    xprintf("phys = (%u %u %u) ",physec, physeh, physes);
    xprintf("logical = (%u %u %u)\n", lec, leh, les);
  }
  // Ending on cylinder boundary? 
  if (physeh != (g_heads - 1) || physes != g_sectors)
    xprintf("Partition %u does not end on cylinder boundary\n", partition + 1);
}

// List the partition details
static void list_partitions(int validate)
{
  struct partition *p;
  uint32_t start_cyl, end_cyl, start_sec, end_sec, blocks, secs;
  char boot, lastchar = '\0', *dev = disk_device;
  int i = 0, len = strlen(disk_device), odds = 0;

  if (validate && !validate_part_buff(MBRbuf)) {
    close(dev_fd);
    toys.exitval = 1;
    xprintf("Device %s: doesn't contain a valid partition table\n", disk_device);
    return;
  }
  if (isdigit(dev[len - 1])) lastchar = 'p';

  xprintf("%*s Boot      Start         End      Blocks  Id System\n", len+1, "Device");
  for (i = 0; i < num_parts; i++) {
    p = partitions[i].part;
    if (is_partition_clear(p)) continue;

    boot = ((p->boot_ind == 0x80)?'*':(!p->boot_ind)?' ':'?');
    start_sec = swap_le32toh(p->start4) + partitions[i].start_offset;
    secs = swap_le32toh(p->size4);

    if ((start_sec + secs) == 0) end_sec = 0;
    else end_sec = start_sec + secs -1;
    start_cyl = start_sec/(g_heads * g_sectors) + 1;
    end_cyl = end_sec/(g_heads * g_sectors) + 1;
    blocks = secs;
    if (g_sect_size < ONE_K) {
      blocks /= (ONE_K/g_sect_size);
      odds = secs %(ONE_K/g_sect_size);
    } else if (g_sect_size > ONE_K) blocks *= (g_sect_size/ONE_K);

    if (lastchar) xprintf("%s%c%d",dev, lastchar, i+1);
    else xprintf("%s%d",dev, i+1);

    xprintf("   %c %11u %11u %11u%c %2x %s\n",
        boot,
        disp_unit_cyl == 0? start_sec: start_cyl,
        disp_unit_cyl == 0? end_sec: end_cyl,
        blocks,odds?'+':' ', p->sys_ind, get_type(p->sys_ind));

    consistency_check(p, i);
  }
  if (check_order()) xprintf("\nPartition table entries are not in disk order");
}

//Print device details
static void print_mbr(int validate)
{
  unsigned long long bytes = ((unsigned long long)total_number_sectors << 9);
  long mbytes = bytes/1000000;

  if (mbytes < 10000) xprintf("Disk %s: %lu MB, %llu bytes\n", disk_device, mbytes, bytes);
  else xprintf("Disk %s: %lu.%lu GB, %llu bytes\n", disk_device, mbytes/1000, (mbytes/100)%10, bytes);
  xprintf("%ld heads, %ld sectors/track, %ld cylinders", g_heads, g_sectors, g_cylinders);
  if (!disp_unit_cyl) {
    xprintf(", total %lld sectors\n", total_number_sectors/(g_sect_size/SECTOR_SIZE));
    xprintf("Units = sectors of 1 * %ld = %ld bytes\n",g_sect_size, g_sect_size);
  } else xprintf("\nUnits = cylinders of %ld * %ld = %ld bytes\n\n",
      g_heads * g_sectors, g_sect_size, g_heads * g_sectors * g_sect_size);
  list_partitions(validate);
  xputc('\n');
}

static void init_members(void)
{
  int i = 0;
  num_parts = 4; //max of primaries in a part table
  disp_unit_cyl = dos_flag = 1;
  extended_offset = 0;
  g_sect_size = SECTOR_SIZE;
  for (i = 0; i < num_parts; i++) {
    partitions[i].part = part_offset(MBRbuf, i);
    partitions[i].sec_buffer = MBRbuf;
    partitions[i].modified = 0;
    partitions[i].start_offset = 0;
  }
}

static int read_input(char *mesg, char *outp)
{
  char *p;
  int size = 0;
  do {
    xprintf("%s", mesg);
    p = fgets(toybuf, 80, stdin);
  
    if (!p || !(size = strlen(p))) exit(0);
    if (p[size-1] == '\n') p[--size] = '\0';
  } while (!size);

  while (*p != '\0' && *p <= ' ') p++;
  if (outp) memcpy(outp, p, strlen(p) + 1); //1 for nul
  return *p;
}

static int read_hex(char *mesg)
{
  int val;
  char input[80], *endp;
  while (1) {
    read_input(mesg, input);
    if ((*input | 0x20) == 'l') {
      list_types();
      memset(input, 0, 80);
      continue;
    }
    val = strtoul(input, &endp, 16);
    if (endp && *endp) continue;
    if (val <= 0xff) return val;
  }
}

/* Delete an exiting partition,
 * if its primary, then just clear the partition details
 * if extended, then clear the partition details, also for logical
 * if only logical, then move the later partitions backwards 1 step
 */
void delete_partition(int i)
{
  int sys_id, looper = 0;
  struct partition *p, *q, *ext_p, *ext_q;
  sector_t new_start;
  struct part_entry *pe = &partitions[i];
  
  if (chs_warn()) return;
  p = pe->part;
  sys_id = p->sys_ind;
  if (!sys_id) xprintf("Partition %u is empty\n", i+1);

  if (i < 4 && !IS_EXTENDED(sys_id)) {
    memset(p, 0, sizeof(struct partition)); //clear_partition
    pe->modified = 1;
  } else if (i < 4 && IS_EXTENDED(sys_id)) {
    memset(p, 0, sizeof(struct partition)); //clear_partition
    pe->modified = 1;
    for (looper = 4; looper < num_parts; looper++) {
      pe = &partitions[looper];
      p = pe->part; 
      if (is_partition_clear(p)) break;
      else {
        memset(p, 0, sizeof(struct partition)); //clear_partition
        pe->modified = 1;
        free(pe->sec_buffer);
      }
    }
    extended_offset = 0;
    num_parts = 4;
  } else {
    //only logical is delete, need to move the rest of them backwards
    if (i == 4) { //move partiton# 6 to 5.
      partitions[i].modified = 1;
      if (num_parts > i+1) {
        q = partitions[i + 1].part;
        *p = *q; //copy the part table
        ext_p = part_offset(partitions[i].sec_buffer, 1);
        ext_q = part_offset(partitions[i + 1].sec_buffer, 1);
        *ext_p = *ext_q; //copy the extended info pointer
        // change the start of the 4th partiton. 
        new_start = partitions[i + 1].start_offset + swap_le32toh(q->start4) - extended_offset;
        new_start = SWAP_LE32(new_start);
        memcpy(p->start4, (void *)&new_start, 4);
      } else {
        memset(partitions[i].part, 0, sizeof(struct partition));
        return; //only logical
      }
    } else if (i > 4) {
      ext_p = part_offset(partitions[i-1].sec_buffer, 1);
      ext_q = part_offset(partitions[i].sec_buffer, 1);
      memcpy((void*)ext_p, (void *)ext_q, sizeof(struct partition));
      partitions[i-1].modified = 1;
    }
    if (i == 4) looper = i+2;
    else if (i > 4) looper = i+1;
    for (; looper < num_parts; looper++)
      partitions[looper-1] = partitions[looper];
    num_parts--;
  }
}

static int ask_partition(int num_parts)
{
  int val;
  while (1) {
    do {
      xprintf("Partition (%u - %u):", 1, num_parts);
      fgets(toybuf, 80, stdin);
    } while (!isdigit(*toybuf));
    val = atoi(toybuf);
    if (val > 0 && val <= num_parts) return val;
    else xprintf("Invalid number entered\n");
  }
}

static void toggle_active_flag(int i)
{
  struct partition *p = partitions[i].part;
  if (is_partition_clear(p)) xprintf("Partition %u is empty\n", i+1);
  
  if (IS_EXTENDED(p->sys_ind) && !p->boot_ind)
    xprintf("WARNING: Partition %u is an extended partition\n", i + 1);
  p->boot_ind = p->boot_ind == 0x80?0 : 0x80;
  partitions[i].modified = 1;
}

//Write the partition details from Buffer to Disk.
void write_table(void)
{
  int i =0;
  struct part_entry *pe;
  sector_t offset;

  for (i = 0; i < 4; i++)
    if (partitions[i].modified) partitions[3].modified = 1;

  for (i = 3; i < num_parts; i++) {
    pe = &partitions[i];
    write_table_flag(pe->sec_buffer);
    offset = pe->start_offset;
    if (pe->modified == 1) {
      xlseek(dev_fd, offset * g_sect_size, SEEK_SET);
      xwrite(dev_fd, pe->sec_buffer, g_sect_size);
    }
  }
  xprintf("The partition table has been altered.\n");
  xprintf("Calling ioctl() to re-read partition table\n");
  sync();
  for (i = 4; i < num_parts; i++) free(partitions[i].sec_buffer);
  if(ioctl(dev_fd, BLKRRPART, NULL) < 0)
    perror_exit("WARNING: rereading partition table failed, kernel still uses old table");

}

/* try to find a partition for deletion, if only
 * one, then select the same, else ask from USER
 */
static int get_non_free_partition(int max)
{       
  int num = -1, i = 0;

  for (i = 0; i < max; i++) {
    if (!is_partition_clear(partitions[i].part)) {
      if (num >= 0)
        return ask_partition(num_parts)-1;
      num = i;
    }
  }
  (num >= 0) ? xprintf("Selected partition %d\n",num+1):
    xprintf("No partition is defined yet!\n");
  return num;
}

/* a try at autodetecting an empty partition table entry,
 * if multiple options then get USER's choce.
 */
static int get_free_partition(int max)
{
  int num = -1, i = 0;

  for (i = 0; i < max; i++) {
    if (is_partition_clear(partitions[i].part)) {
      if (num >= 0)
        return ask_partition(4)-1;
      num = i;
    }
  }
  (num >= 0) ? xprintf("Selected partition %d\n",num+1):
    xprintf("All primary partitions have been defined already!\n");
  return num;
}

//taking user input for partition start/end sectors/cyinders
static uint32_t ask_value(char *mesg, sector_t left, sector_t right, sector_t defalt)
{ 
  char *str = toybuf;
  uint32_t val;
  int use_default = 1;

  while (1) {
    use_default = 1;
    do {
      xprintf("%s",mesg);
      fgets(str, 80, stdin);
    } while (!isdigit(*str) && (*str != '\n')
        && (*str != '-') && (*str != '+') && (!isblank(*str)));
    while (isblank(*str)) str++; //remove leading white spaces
    if (*str == '+' || *str == '-') {
      int minus = (*str == '-');
      int absolute = 0;

      val = atoi(str + 1);
      while (isdigit(*++str)) use_default = 0;

      switch (*str) {
        case 'c':
        case 'C':
          if (!disp_unit_cyl) val *= g_heads * g_sectors;
          break;
        case 'K':
          absolute = ONE_K;
          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 long) val * absolute;
        unsigned long unit = (disp_unit_cyl && (g_heads * g_sectors))? g_heads * g_sectors : 1;

        unit = unit * g_sect_size;
        bytes += unit/2; // rounding
        bytes /= unit;
        val = bytes;
      }
      if (minus)
        val = -val;
      val += left;
    } else {
      val = atoi(str);
      while (isdigit(*str)) {
        str++;
        use_default = 0;
      }
    }
    if(use_default) {
      val = defalt;
      xprintf("Using default value %lld\n", defalt);
    }
    if (val >= left && val <= right) return val;
    else xprintf("Value out of range\n");
  }
}

//validating if the start given falls in a limit or not
static int validate(int start_index, sector_t* begin,sector_t* end, sector_t start
    , int asked)
{
  int i, valid = 0;
  for (i = start_index; i < num_parts; i++) {
    if (start >= begin[i] && start <= end[i]) {
      if (asked) xprintf("Sector %lld is already allocated\n",start);
      valid = 0;
      break;
    } else valid = 1;
  }
  return valid;
}

//get the start sector/cylinder of a new partition
static sector_t ask_start_sector(int idx, sector_t* begin, sector_t* end, int ext_idx)
{
  sector_t start, limit, temp = 0, start_cyl, limit_cyl, offset = 1;
  char mesg[256];
  int i, asked = 0, valid = 0, start_index = 0;

  if (dos_flag) offset = g_sectors;
  start = offset;
  if (disp_unit_cyl) limit = (sector_t)g_sectors * g_heads * g_cylinders - 1;
  else limit = total_number_sectors - 1;

  if (disp_unit_cyl) //make the begin of every partition to cylnder boundary 
    for (i = 0; i < num_parts; i++)
      begin[i] = (begin[i]/(g_heads* g_sectors)) * (g_heads* g_sectors);

  if (idx >= 4) {
    if (!begin[ext_idx] && extended_offset) begin[ext_idx] = extended_offset;
    start = begin[ext_idx] + offset;
    limit = end[ext_idx];
    start_index = 4;
  }
  do {
    if (asked) valid = validate(start_index, begin, end, start, asked);
    if (valid) break;

    do {
      for (i = start_index; i < num_parts; i++) 
        if (start >= begin[i] && start <= end[i])
          start = end[i] + 1 + ((idx >= 4)? offset : 0);
    } while (!validate(start_index, begin, end, start, 0));

    start_cyl = start/(g_sectors * g_heads) + 1;
    limit_cyl = limit/(g_sectors * g_heads) + 1;

    if (start > limit) break;
    sprintf(mesg, "First %s (%lld - %lld, default %lld): ", disp_unit_cyl? "cylinder" : "sector",
        (long long int)(disp_unit_cyl? start_cyl : start), 
        (long long int)(disp_unit_cyl? limit_cyl : limit),
        (long long int)(disp_unit_cyl? start_cyl : start));
    temp = ask_value(mesg, disp_unit_cyl? start_cyl : start, 
        disp_unit_cyl? limit_cyl : limit, disp_unit_cyl? start_cyl : start);
    asked = 1;

    if (disp_unit_cyl) {
      // point to the cylinder start sector
      temp = (temp-1) * g_heads * g_sectors;
      if (temp < start) //the boundary is falling in the already used sectors.
        temp = start;
    }
    start = temp;
  } while (asked && !valid);
  return start;
}

//get the end sector/cylinder of a new partition
static sector_t ask_end_sector(int idx, sector_t* begin, sector_t* end, int ext_idx, sector_t start_sec)
{
  sector_t limit, temp = 0, start_cyl, limit_cyl, start = start_sec;
  char mesg[256];
  int i;

  if (disp_unit_cyl) limit = (sector_t)g_sectors * g_heads * g_cylinders - 1;
  else limit = total_number_sectors - 1;

  if (disp_unit_cyl) //make the begin of every partition to cylnder boundary
    for (i = 0; i < num_parts; i++)
      begin[i] = (begin[i]/(g_heads* g_sectors)) * (g_heads* g_sectors);

  if (idx >= 4) limit = end[ext_idx];

  for (i = 0; i < num_parts; i++) {
    struct part_entry *pe = &partitions[i];
    if (start < pe->start_offset && limit >= pe->start_offset) limit = pe->start_offset - 1;
    if (start < begin[i] && limit >= begin[i]) limit = begin[i] - 1;
  }

  start_cyl = start/(g_sectors * g_heads) + 1;
  limit_cyl = limit/(g_sectors * g_heads) + 1;
  if (limit < start) { //the boundary is falling in the already used sectors.
    xprintf("No Free sectors available\n");
    return 0;
  }
  sprintf(mesg, "Last %s or +size or +sizeM or +sizeK (%lld - %lld, default %lld): ",
      disp_unit_cyl? "cylinder" : "sector",
      (long long int)(disp_unit_cyl? start_cyl : start), 
      (long long int)(disp_unit_cyl? limit_cyl : limit),
      (long long int)(disp_unit_cyl? limit_cyl : limit));
  temp = ask_value(mesg, disp_unit_cyl? start_cyl : start, 
      disp_unit_cyl? limit_cyl : limit, disp_unit_cyl? limit_cyl : limit);

  if (disp_unit_cyl) { // point to the cylinder start sector
    temp = temp * g_heads * g_sectors - 1;
    if (temp > limit) temp = limit;
  }
  if (temp < start) { //the boundary is falling in the already used sectors.
    xprintf("No Free sectors available\n");
    return 0;
  }
  return temp;
}

// add a new partition to the partition table
static int add_partition(int idx, int sys_id)
{
  int i, ext_idx = -1;
  sector_t start, end, begin_sec[num_parts], end_sec[num_parts];
  struct part_entry *pe = &partitions[idx];
  struct partition *p = pe->part;

  if (p && !is_partition_clear(p)) {
    xprintf("Partition %u is already defined, delete it to re-add\n", idx+1);
    return 0;
  }
  for (i = 0; i < num_parts; i++) {
    pe = &partitions[i];
    p = pe->part;
    if (is_partition_clear(p)) {
      begin_sec[i] = 0xffffffff;
      end_sec[i] = 0;
    } else {
      begin_sec[i] = swap_le32toh(p->start4) + pe->start_offset;
      end_sec[i] = begin_sec[i] + swap_le32toh(p->size4) - 1;
    }
    if (IS_EXTENDED(p->sys_ind)) ext_idx = i;
  }
  start = ask_start_sector(idx, begin_sec, end_sec, ext_idx);
  end = ask_end_sector(idx, begin_sec, end_sec, ext_idx, start);
  if (!end) return 0;
  //Populate partition table entry  - 16 bytes
  pe = &partitions[idx];
  p = pe->part;

  if (idx > 4) {
    if (dos_flag) pe->start_offset = start - (sector_t)g_sectors;
    else pe->start_offset = start - 1;
    if (pe->start_offset == extended_offset) pe->start_offset++;
    if (!dos_flag) start++;
  }
 
  set_levalue(p->start4, start - pe->start_offset);
  set_levalue(p->size4, end - start + 1);
  set_hsc(p, start, end);
  p->boot_ind = 0;
  p->sys_ind = sys_id;
  pe->modified = 1;

  if (idx > 4) {
    p = partitions[idx-1].part + 1; //extended pointer for logical partitions
    set_levalue(p->start4, pe->start_offset - extended_offset);
    set_levalue(p->size4, end - start + 1 + (dos_flag? g_sectors: 1));
    set_hsc(p, pe->start_offset, end);
    p->boot_ind = 0;  
    p->sys_ind = EXTENDED;
    partitions[idx-1].modified = 1;   
  }
  if (IS_EXTENDED(sys_id)) {
    pe = &partitions[4];
    pe->modified = 1; 
    pe->sec_buffer = xzalloc(g_sect_size);
    pe->part = part_offset(pe->sec_buffer, 0);
    pe->start_offset = extended_offset = start;
    num_parts = 5;
  }
  return 1;
}

static void add_logical_partition(void)
{
  struct part_entry *pe;
  if (num_parts > 5 || !is_partition_clear(partitions[4].part)) {
    pe = &partitions[num_parts];
    pe->modified = 1;
    pe->sec_buffer = xzalloc(g_sect_size);
    pe->part = part_offset(pe->sec_buffer, 0);
    pe->start_offset = 0;
    num_parts++;
    if (!add_partition(num_parts - 1, LINUX_NATIVE)) {
      num_parts--;
      free(pe->sec_buffer);
    }
  } 
  else add_partition(num_parts -1, LINUX_NATIVE);
}

/* Add a new partiton to the partition table.
 * MAX partitions limit is taken to be 60, can be changed
 */
static void add_new_partition(void)
{
  int choice, idx, i, free_part = 0;
  char *msg = NULL;
  
  if (chs_warn()) return;
  for (i = 0; i < 4; i++) if(is_partition_clear(partitions[i].part)) free_part++;

  if (!free_part && num_parts >= 60) {
    xprintf("The maximum number of partitions has been created\n");
    return;       
  }
  if (!free_part) {
    if (extended_offset) add_logical_partition();
    else xprintf("You must delete some partition and add "
          "an extended partition first\n");
    return;
  }

  msg = xmprintf("  %s\n  p  primary partition(1-4)\n",
          extended_offset? "l  logical (5 or over)" : "e  extended");

  choice = 0x20 | read_input(msg, NULL);
  free(msg);
  if (choice == 'p') {
    idx = get_free_partition(4);
    if (idx >= 0) add_partition(idx, LINUX_NATIVE);
    return;
  }
  if (choice =='l' && extended_offset) {
    add_logical_partition();
    return;
  }
  if (choice == 'e' && !extended_offset) {
    idx = get_free_partition(4);   
    if (idx >= 0) add_partition(idx, EXTENDED);
    return;
  }
}

static void change_systype(void )
{
  int i, sys_id;
  struct partition *p;
  struct part_entry *pe;

  i = ask_partition(num_parts);
  pe = &partitions[i-1];
  p = pe->part;
  if (is_partition_clear(p)) {
    xprintf("Partition %d doesn't exist yet!\n", i);
    return;
  }
  sys_id = read_hex("Hex code (L to list codes): ");
  if ((IS_EXTENDED(p->sys_ind) && !IS_EXTENDED(sys_id)) ||
      (!IS_EXTENDED(p->sys_ind) && IS_EXTENDED(sys_id))) {
    xprintf("you can't change a  partition to an extended or vice-versa\n");
    return;
  }

  xprintf("Changed system type of partition %u to %0x (%s)\n",i, sys_id, get_type(sys_id));
  p->sys_ind = sys_id;
  pe->modified = 1;
}

static void check(int n, unsigned h, unsigned s, unsigned c, sector_t start)
{   
  sector_t total, real_s, real_c;

  real_s = sector(s) - 1;
  real_c = cylinder(s, c);
  total = (real_c * g_sectors + real_s) * g_heads + h;
  if (!total) xprintf("Partition %u contains sector 0\n", n);
  if (h >= g_heads)
    xprintf("Partition %u: head %u greater than maximum %lu\n", n, h + 1, g_heads);
  if (real_s >= g_sectors)
    xprintf("Partition %u: sector %u greater than maximum %lu\n", n, s, g_sectors);
  if (real_c >= g_cylinders)
    xprintf("Partition %u: cylinder %lld greater than maximum %lu\n", n, real_c + 1, g_cylinders);
  if (g_cylinders <= ONE_K && start != total)
    xprintf("Partition %u: previous sectors %lld disagrees with total %lld\n", n, start, total);
}

static void verify_table(void)
{
  int i, j, ext_idx = -1;
  sector_t begin_sec[num_parts], end_sec[num_parts], total = 1;
  struct part_entry *pe;
  struct partition *p;

  for (i = 0; i < num_parts; i++) {
    pe = &partitions[i];
    p = pe->part;
    if (is_partition_clear(p) || IS_EXTENDED(p->sys_ind)) {
      begin_sec[i] = 0xffffffff;
      end_sec[i] = 0;
    } else {
      begin_sec[i] = swap_le32toh(p->start4) + pe->start_offset;
      end_sec[i] = begin_sec[i] + swap_le32toh(p->size4) - 1;
    }
    if (IS_EXTENDED(p->sys_ind)) ext_idx = i;
  }
  for (i = 0; i < num_parts; i++) {
    pe = &partitions[i];
    p = pe->part;
    if (p->sys_ind && !IS_EXTENDED(p->sys_ind)) {
      consistency_check(p, i);
      if ((swap_le32toh(p->start4) + pe->start_offset) < begin_sec[i])
        xprintf("Warning: bad start-of-data in partition %u\n", i + 1);
      check(i + 1, p->end_head, p->end_sector, p->end_cyl, end_sec[i]);
      total += end_sec[i] + 1 - begin_sec[i];
      for (j = 0; j < i; j++) {
        if ((begin_sec[i] >= begin_sec[j] && begin_sec[i] <= end_sec[j])
            || ((end_sec[i] <= end_sec[j] && end_sec[i] >= begin_sec[j]))) {
          xprintf("Warning: partition %u overlaps partition %u\n", j + 1, i + 1);
          total += begin_sec[i] >= begin_sec[j] ? begin_sec[i] : begin_sec[j];
          total -= end_sec[i] <= end_sec[j] ? end_sec[i] : end_sec[j];
        }
      }
    }
  }  
  if (extended_offset) {
    struct part_entry *pex = &partitions[ext_idx];
    sector_t e_last = swap_le32toh(pex->part->start4) +
      swap_le32toh(pex->part->size4) - 1;

    for (i = 4; i < num_parts; i++) {
      total++;
      p = partitions[i].part;
      if (!p->sys_ind) {
        if (i != 4 || i + 1 < num_parts)
          xprintf("Warning: partition %u is empty\n", i + 1);
      } else if (begin_sec[i] < extended_offset || end_sec[i] > e_last)
        xprintf("Logical partition %u not entirely in partition %u\n", i + 1, ext_idx + 1);
    }
  }
  if (total > g_heads * g_sectors * g_cylinders)
    xprintf("Total allocated sectors %lld greater than the maximum "
        "%lu\n", total, g_heads * g_sectors * g_cylinders);
  else {
    total = g_heads * g_sectors * g_cylinders - total;
    if (total) xprintf("%lld unallocated sectors\n", total);
  }
}

static void move_begning(int idx)
{
  sector_t start, num, new_start, end;
  char mesg[256];
  struct part_entry *pe = &partitions[idx];
  struct partition *p = pe->part;

  if (chs_warn()) return;
  start = swap_le32toh(p->start4) + pe->start_offset;
  num = swap_le32toh(p->size4);
  end = start + num -1;

  if (!num || IS_EXTENDED(p->sys_ind)) {
    xprintf("Partition %u doesn't have data area\n", idx+1);
    return;
  }
  sprintf(mesg, "New begining of data (0 - %lld, default %lld): ", 
      (long long int)(end), (long long int)(start));
  new_start = ask_value(mesg, 0, end, start);
  if (new_start != start) {
    set_levalue(p->start4, new_start - pe->start_offset);
    set_levalue(p->size4, end - new_start +1);
    if ((read_input("Recalculate C/H/S (Y/n): ", NULL) | 0x20) == 'y')
      set_hsc(p, new_start, end);
    pe->modified = 1;
  }
}

static void print_raw_sectors()
{
  int i, j;
  struct part_entry *pe;

  xprintf("Device: %s\n", disk_device);
  for (i = 3; i < num_parts; i++) {
    pe = &partitions[i];
    for (j = 0; j < g_sect_size; j++) {
      if (!(j % 16)) xprintf("\n0x%03X: ",j);
      xprintf("%02X ",pe->sec_buffer[j]);
    }
    xputc('\n');
  }
}

static void print_partitions_list(int ext)
{
  int i;                                                                                    
  struct part_entry *pe;
  struct partition *p;

  xprintf("Disk %s: %lu heads, %lu sectors, %lu cylinders\n\n", disk_device, g_heads, g_sectors, g_cylinders);
  xprintf("Nr AF  Hd Sec  Cyl  Hd Sec  Cyl      Start       Size ID\n");

  for (i = 0; i < num_parts; i++) {
    pe = &partitions[i];
    p = pe->part;
    if (p) {
      if (ext && (i >= 4)) p = pe->part + 1;
      if(ext && i < 4 && !IS_EXTENDED(p->sys_ind)) continue;

      xprintf("%2u %02x%4u%4u%5u%4u%4u%5u%11u%11u %02x\n",
          i+1, p->boot_ind, p->head,
          sector(p->sector), cylinder(p->sector, p->cyl),
          p->end_head,           
          sector(p->end_sector), cylinder(p->end_sector, p->end_cyl),
          swap_le32toh(p->start4),
          swap_le32toh(p->size4),
          p->sys_ind);
      if (p->sys_ind) consistency_check(p, i);
    }
  }
}

//fix the partition table order to ascending
static void fix_order(void)
{
  sector_t first[num_parts], min;
  int i, j, oj, ojj, sj, sjj;
  struct part_entry *pe;
  struct partition *px, *py, temp, *pj, *pjj, tmp;

  for (i = 0; i < num_parts; i++) {
    pe = &partitions[i];
    px = pe->part;
    if (is_partition_clear(px)) first[i] = 0xffffffff;
    else first[i] = swap_le32toh(px->start4) + pe->start_offset;
  }
  
  if (!check_order()) {
    xprintf("Ordering is already correct\n\n");
    return;
  }
  for (i = 0; i < 4; i++) {
    for (j = 0; j < 3; j++) {
      if (first[j] > first[j+1]) {
        py = partitions[j+1].part;
        px = partitions[j].part;
        memcpy(&temp, py, sizeof(struct partition));
        memcpy(py, px, sizeof(struct partition));
        memcpy(px, &temp, sizeof(struct partition));
        min = first[j+1];
        first[j+1] = first[j];
        first[j] = min;
        partitions[j].modified = 1;
      }
    }
  }
  for (i = 5; i < num_parts; i++) {
    for (j = 5; j < num_parts - 1; j++) {
      oj = partitions[j].start_offset;
      ojj = partitions[j+1].start_offset;
      if (oj > ojj) {
        partitions[j].start_offset = ojj;
        partitions[j+1].start_offset = oj;
        pj = partitions[j].part;
        set_levalue(pj->start4, swap_le32toh(pj->start4)+oj-ojj);
        pjj = partitions[j+1].part;
        set_levalue(pjj->start4, swap_le32toh(pjj->start4)+ojj-oj);
        set_levalue((partitions[j-1].part+1)->start4, ojj-extended_offset);
        set_levalue((partitions[j].part+1)->start4, oj-extended_offset);
      }
    }
  }
  for (i = 4; i < num_parts; i++) {
    for (j = 4; j < num_parts - 1; j++) {
      pj = partitions[j].part;
      pjj = partitions[j+1].part;
      sj = swap_le32toh(pj->start4);
      sjj = swap_le32toh(pjj->start4);
      oj = partitions[j].start_offset;
      ojj = partitions[j+1].start_offset;
      if (oj+sj > ojj+sjj) {
        tmp = *pj;
        *pj = *pjj;
        *pjj = tmp;
        set_levalue(pj->start4, ojj+sjj-oj);
        set_levalue(pjj->start4, oj+sj-ojj);
      }  
    }    
  }
  // If anything changed 
  for (j = 4; j < num_parts; j++) partitions[j].modified = 1;
  xprintf("Done!\n");
}

static void print_menu(void)
{
  xprintf("a\ttoggle a bootable flag\n"
  "b\tedit bsd disklabel\n"
  "c\ttoggle the dos compatibility flag\n"
  "d\tdelete a partition\n"
  "l\tlist known partition types\n"
  "n\tadd a new partition\n"
  "o\tcreate a new empty DOS partition table\n"
  "p\tprint the partition table\n"
  "q\tquit without saving changes\n"
  "s\tcreate a new empty Sun disklabel\n"
  "t\tchange a partition's system id\n"
  "u\tchange display/entry units\n"
  "v\tverify the partition table\n"
  "w\twrite table to disk and exit\n"
  "x\textra functionality (experts only)\n");
}

static void print_xmenu(void)
{
  xprintf("b\tmove beginning of data in a partition\n"
  "c\tchange number of cylinders\n"
  "d\tprint the raw data in the partition table\n"
  "e\tlist extended partitions\n"
  "f\tfix partition order\n"  
  "h\tchange number of heads\n"
  "p\tprint the partition table\n"
  "q\tquit without saving changes\n"
  "r\treturn to main menu\n"
  "s\tchange number of sectors/track\n"
  "v\tverify the partition table\n"
  "w\twrite table to disk and exit\n");
}

static void expert_menu(void)
{
  int choice, idx;
  sector_t value;
  char mesg[256];

  while (1) {
    xputc('\n');
    char *msg = "Expert Command ('m' for help): ";
    choice = 0x20 | read_input(msg, NULL);
    switch (choice) {
      case 'b': //move data begining in partition
        idx = ask_partition(num_parts);
        move_begning(idx - 1);
        break;
      case 'c': //change cylinders
          sprintf(mesg, "Number of cylinders (1 - 1048576, default %lu): ", g_cylinders);
          value = ask_value(mesg, 1, 1048576, g_cylinders);
          g_cylinders = TT.cylinders = value;
          toys.optflags |= FLAG_C;
          if(g_cylinders > ONE_K)
            xprintf("\nThe number of cylinders for this disk is set to %lu.\n"
                "There is nothing wrong with that, but this is larger than 1024,\n"
                "and could in certain setups cause problems.\n", g_cylinders);
        break;
      case 'd': //print raw data in part tables
        print_raw_sectors();
        break;
      case 'e': //list extended partitions
        print_partitions_list(1);
        break;
      case 'f': //fix part order
        fix_order();
        break;
      case 'h': //change number of heads
          sprintf(mesg, "Number of heads (1 - 256, default %lu): ", g_heads);
          value = ask_value(mesg, 1, 256, g_heads);
          g_heads = TT.heads = value;
          toys.optflags |= FLAG_H;
        break;
      case 'p': //print partition table
        print_partitions_list(0);
        break;
      case 'q':
        free_bufs();
        close(dev_fd);
        xputc('\n');
        exit(0);
        break;
      case 'r':
        return;
        break;
      case 's': //change sector/track
          sprintf(mesg, "Number of sectors (1 - 63, default %lu): ", g_sectors);
          value = ask_value(mesg, 1, 63, g_sectors);
          g_sectors = TT.sectors = value;
          toys.optflags |= FLAG_H;
        break;
      case 'v':
        verify_table();
        break;
      case 'w':
        write_table();
        toys.exitval = 0;
        exit(0);
        break;
      case 'm':
        print_xmenu();
        break;
      default:
        xprintf("Unknown command '%c'\n",choice);
        print_xmenu();
        break;
    }
  } //while(1)
}

static int disk_proper(const char *device)
{
  unsigned length;
  int fd = open(device, O_RDONLY);

  if (fd != -1) {
    struct hd_geometry dev_geo;
    dev_geo.heads = 0;
    dev_geo.sectors = 0;
    int err = ioctl(fd, HDIO_GETGEO, &dev_geo);
    close(fd);
    if (!err) return (dev_geo.start == 0);
  }
  length = strlen(device);
  if (length != 0 && isdigit(device[length - 1])) return 0;
  return 1;
}

static void reset_entries()
{
  int i;

  memset(MBRbuf, 0, sizeof(MBRbuf));
  for (i = 4; i < num_parts; i++)
    memset(&partitions[i], 0, sizeof(struct part_entry));
}

//this will keep dev_fd = 3 always alive
static void move_fd()
{
  int fd = xopen("/dev/null", O_RDONLY);
  if(fd != dev_fd) {
    if(dup2(fd, dev_fd) != dev_fd) perror_exit("Can't dup2");
    close(fd);
  }
}

/* Read proc/partitions and then print the details
 * for partitions on each device
 */
static void read_and_print_parts()
{
  unsigned int ma, mi, sz;
  char *name = toybuf, *buffer = toybuf + ONE_K, *device = toybuf + 2048;
  FILE* fp = xfopen("/proc/partitions", "r");

  while (fgets(buffer, ONE_K, fp)) {
    reset_entries();
    num_parts = 4;
    memset(name, 0, sizeof(name));
    if (sscanf(buffer, " %u %u %u %[^\n ]", &ma, &mi, &sz, name) != 4)
      continue;
      
    sprintf(device,"/dev/%s",name);
    if (disk_proper(device)) {
      if (read_mbr(device, 0)) continue;
      print_mbr(1);
      move_fd();
    }
  }
  fclose(fp);
}

void fdisk_main(void)
{
  int choice, p;

  init_members();
  move_fd();
  if (TT.heads >= 256) TT.heads = 0;
  if (TT.sectors >= 64) TT.sectors = 0;
  if (toys.optflags & FLAG_u) disp_unit_cyl = 0;
  if (toys.optflags & FLAG_l) {
    if (!toys.optc) read_and_print_parts();
    else {
      while(*toys.optargs){
        if (read_mbr(*toys.optargs, 0)) {
          toys.optargs++;
          continue;
        }
        print_mbr(1);
        move_fd();
        toys.optargs++;
      }
    }
    toys.exitval = 0;
    return;
  } else {
    if (toys.optc != 1) help_exit(0);
    if (read_mbr(toys.optargs[0], 1)) return;
    while (1) {
      xputc('\n');
      char *msg = "Command ('m' for help): ";
      choice = 0x20 | read_input(msg, NULL);
      switch (choice) {
        case 'a':
          p = ask_partition(num_parts);
          toggle_active_flag(p - 1); //partition table index start from 0.
          break;
        case 'b':
          break;
        case 'c':
          dos_flag = !dos_flag;
          xprintf("Dos compatible flag is %s\n", dos_flag?"Set" : "Not set");
          break;
        case 'd':
          p = get_non_free_partition(num_parts); //4 was here
          if(p >= 0) delete_partition(p);
          break;
        case 'l':
          list_types();
          break;
        case 'n': //add new partition
          add_new_partition();
          break;
        case 'o':
          create_empty_doslabel();
          break;
        case 'p':
          print_mbr(0);
          break;
        case 'q':
          free_bufs();
          close(dev_fd);
          xputc('\n');
          exit(0);
          break;
        case 's':
          break;
        case 't':
          change_systype();
          break;
        case 'u':
          disp_unit_cyl = !disp_unit_cyl;
          xprintf("Changing Display/Entry units to %s\n",disp_unit_cyl?"cylinders" : "sectors");
          break;
        case 'v':
          verify_table();
          break;
        case 'w':
          write_table();
          toys.exitval = 0;
          return;
          break;
        case 'x':
          expert_menu();
          break;
        case 'm':
          print_menu();
          break;
        default:
          xprintf("%c: Unknown command\n",choice);
          break;
      }
    } //while(1)
  }
}