aboutsummaryrefslogtreecommitdiff
path: root/hex.c
blob: fded810ac9b15bf41a6461224aafd531b3d659f0 (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
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
/*
 * hex -- hex viewer
 *
 * Copyright (c) 2016 - 2017, Přemysl Janouch <p.janouch@gmail.com>
 * All rights reserved.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

#include "config.h"

// We "need" to have an enum for attributes before including liberty.
// Avoiding colours in the defaults here in order to support dumb terminals.
#define ATTRIBUTE_TABLE(XX)                                    \
	XX( FOOTER,     "footer",     -1,  -1, 0                  ) \
	XX( FOOTER_HL,  "footer_hl",  -1,  -1, A_BOLD             ) \
	/* Bar                                                   */ \
	XX( BAR,        "bar",        -1,  -1, A_REVERSE          ) \
	XX( BAR_HL,     "bar_hl",     -1,  -1, A_REVERSE | A_BOLD ) \
	/* View                                                  */ \
	XX( EVEN,       "even",       -1,  -1, 0                  ) \
	XX( ODD,        "odd",        -1,  -1, 0                  ) \
	XX( SELECTION,  "selection",  -1,  -1, A_REVERSE          ) \
	/* Field highlights                                      */ \
	XX( C1,         "c1",         22, 194, 0                  ) \
	XX( C2,         "c2",         88, 224, 0                  ) \
	XX( C3,         "c3",         58, 229, 0                  ) \
	XX( C4,         "c4",         20, 189, 0                  ) \
	/* These are for debugging only                          */ \
	XX( WARNING,    "warning",     3,  -1, 0                  ) \
	XX( ERROR,      "error",       1,  -1, 0                  )

enum
{
#define XX(name, config, fg_, bg_, attrs_) ATTRIBUTE_ ## name,
	ATTRIBUTE_TABLE (XX)
#undef XX
	ATTRIBUTE_COUNT
};

// User data for logger functions to enable formatted logging
#define print_fatal_data    ((void *) ATTRIBUTE_ERROR)
#define print_error_data    ((void *) ATTRIBUTE_ERROR)
#define print_warning_data  ((void *) ATTRIBUTE_WARNING)

#define LIBERTY_WANT_POLLER
#define LIBERTY_WANT_ASYNC
#define LIBERTY_WANT_PROTO_HTTP
#include "liberty/liberty.c"

#include <locale.h>
#include <termios.h>
#ifndef TIOCGWINSZ
#include <sys/ioctl.h>
#endif  // ! TIOCGWINSZ

#include "tui.c"
#include "termo.h"

#ifdef HAVE_LUA
#include <lua.h>
#include <lualib.h>
#include <lauxlib.h>

#include <dirent.h>
#endif // HAVE_LUA

#define APP_TITLE  PROGRAM_NAME         ///< Left top corner

// --- Utilities ---------------------------------------------------------------

// The standard endwin/refresh sequence makes the terminal flicker
static void
update_curses_terminal_size (void)
{
#if defined (HAVE_RESIZETERM) && defined (TIOCGWINSZ)
	struct winsize size;
	if (!ioctl (STDOUT_FILENO, TIOCGWINSZ, (char *) &size))
	{
		char *row = getenv ("LINES");
		char *col = getenv ("COLUMNS");
		unsigned long tmp;
		resizeterm (
			(row && xstrtoul (&tmp, row, 10)) ? tmp : size.ws_row,
			(col && xstrtoul (&tmp, col, 10)) ? tmp : size.ws_col);
	}
#else  // HAVE_RESIZETERM && TIOCGWINSZ
	endwin ();
	refresh ();
#endif  // HAVE_RESIZETERM && TIOCGWINSZ
}

// --- Simple array support ----------------------------------------------------

// Primitives for arrays

#define ARRAY(type, name) type *name; size_t name ## _len, name ## _size;
#define ARRAY_INIT(a)                                                          \
	BLOCK_START                                                                \
		a = xcalloc (sizeof *a, (a ## _size = 16));                            \
		a ## _len = 0;                                                         \
	BLOCK_END
#define ARRAY_RESERVE(a, n)                                                    \
	array_reserve ((void **) &a, sizeof *a, a ## _len + n, &a ## _size)

static void
array_reserve (void **array, size_t element_size, size_t len, size_t *size)
{
	while (len > *size)
		*array = xreallocarray (*array, element_size, *size <<= 1);
}

// --- Application -------------------------------------------------------------

enum
{
	ROW_SIZE = 16,                      ///< How many bytes on a row
};

enum endianity
{
	ENDIANITY_LE,                       ///< Little endian
	ENDIANITY_BE                        ///< Big endian
};

struct mark
{
	int64_t offset;                     ///< Offset of the mark
	int64_t len;                        ///< Length of the mark
	size_t description;                 ///< Textual description string offset
};

// XXX: can we avoid constructing the marks_by_offset lookup array?
//   How much memory is it even going to consume in reality?

/// This is the final result suitable for display, including unmarked areas.
/// We might infer `color` from the index of this entry but then unmarked areas
/// would skip a color, which is undesired.
struct marks_by_offset
{
	int64_t offset;                     ///< Offset in the file
	struct mark **marks;                ///< Sentinelled array of mark pointers
	int color;                          ///< Color of the area until next offset
};

static struct app_context
{
	// Event loop:

	struct poller poller;               ///< Poller
	bool quitting;                      ///< Quit signal for the event loop
	bool polling;                       ///< The event loop is running

	struct poller_fd tty_event;         ///< Terminal input event
	struct poller_fd signal_event;      ///< Signal FD event

#ifdef HAVE_LUA
	lua_State *L;                       ///< Lua state
	int ref_format;                     ///< Reference to "string.format"
	struct str_map coders;              ///< Map of coders by name
#endif // HAVE_LUA

	// Data:

	char *message;                      ///< Last logged message
	int message_attr;                   ///< Attributes for the logged message

	struct config config;               ///< Program configuration
	char *filename;                     ///< Target filename

	uint8_t *data;                      ///< Target data
	int64_t data_len;                   ///< Length of the data
	int64_t data_offset;                ///< Offset of the data within the file

	// Field marking:

	ARRAY (struct mark, marks)          ///< Marks
	struct str mark_strings;            ///< Storage for mark descriptions

	ARRAY (struct marks_by_offset, marks_by_offset)

	// View:

	int64_t view_top;                   ///< Offset of the top of the screen
	int64_t view_cursor;                ///< Offset of the cursor
	bool view_skip_nibble;              ///< Half-byte offset

	enum endianity endianity;           ///< Endianity

	// Emulated widgets:

	struct poller_idle refresh_event;   ///< Refresh the screen

	// Terminal:

	termo_t *tk;                        ///< termo handle
	struct poller_timer tk_timer;       ///< termo timeout timer
	bool locale_is_utf8;                ///< The locale is Unicode

	struct attrs attrs[ATTRIBUTE_COUNT];
}
g_ctx;

/// Shortcut to retrieve named terminal attributes
#define APP_ATTR(name) g_ctx.attrs[ATTRIBUTE_ ## name].attrs

// --- Configuration -----------------------------------------------------------

static struct config_schema g_config_colors[] =
{
#define XX(name_, config, fg_, bg_, attrs_) \
	{ .name = config, .type = CONFIG_ITEM_STRING },
	ATTRIBUTE_TABLE (XX)
#undef XX
	{}
};

static const char *
get_config_string (struct config_item *root, const char *key)
{
	struct config_item *item = config_item_get (root, key, NULL);
	hard_assert (item);
	if (item->type == CONFIG_ITEM_NULL)
		return NULL;
	hard_assert (config_item_type_is_string (item->type));
	return item->value.string.str;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static void
load_config_colors (struct config_item *subtree, void *user_data)
{
	config_schema_apply_to_object (g_config_colors,   subtree, user_data);

	// The attributes cannot be changed dynamically right now, so it doesn't
	// make much sense to make use of "on_change" callbacks either.
	// For simplicity, we should reload the entire table on each change anyway.
	const char *value;
#define XX(name, config, fg_, bg_, attrs_) \
	if ((value = get_config_string (subtree, config))) \
		g_ctx.attrs[ATTRIBUTE_ ## name] = attrs_decode (value);
	ATTRIBUTE_TABLE (XX)
#undef XX
}

static void
app_load_configuration (void)
{
	struct config *config = &g_ctx.config;
	config_register_module (config, "colors", load_config_colors, NULL);

	// Bootstrap configuration, so that we can access schema items at all
	config_load (config, config_item_object ());

	char *filename = resolve_filename
		(PROGRAM_NAME ".conf", resolve_relative_config_filename);
	if (!filename)
		return;

	struct error *e = NULL;
	struct config_item *root = config_read_from_file (filename, &e);
	free (filename);

	if (e)
	{
		print_error ("error loading configuration: %s", e->message);
		error_free (e);
		exit (EXIT_FAILURE);
	}
	if (root)
	{
		config_load (&g_ctx.config, root);
		config_schema_call_changed (g_ctx.config.root);
	}
}

// --- Application -------------------------------------------------------------

static void
app_init_attributes (void)
{
#define XX(name, config, fg_, bg_, attrs_)          \
	g_ctx.attrs[ATTRIBUTE_ ## name].fg    = fg_;    \
	g_ctx.attrs[ATTRIBUTE_ ## name].bg    = bg_;    \
	g_ctx.attrs[ATTRIBUTE_ ## name].attrs = attrs_;
	ATTRIBUTE_TABLE (XX)
#undef XX
}

static void
app_init_context (void)
{
	poller_init (&g_ctx.poller);
	config_init (&g_ctx.config);

	ARRAY_INIT (g_ctx.marks);
	str_init (&g_ctx.mark_strings);
	ARRAY_INIT (g_ctx.marks_by_offset);

	// This is also approximately what libunistring does internally,
	// since the locale name is canonicalized by locale_charset().
	// Note that non-Unicode locales are handled pretty inefficiently.
	g_ctx.locale_is_utf8 = !strcasecmp_ascii (locale_charset (), "UTF-8");

	app_init_attributes ();
}

static void
app_init_terminal (void)
{
	TERMO_CHECK_VERSION;
	if (!(g_ctx.tk = termo_new (STDIN_FILENO, NULL, 0)))
		abort ();
	if (!initscr () || nonl () == ERR)
		abort ();

	// By default we don't use any colors so they're not required...
	if (start_color () == ERR
	 || use_default_colors () == ERR
	 || COLOR_PAIRS <= ATTRIBUTE_COUNT)
		return;

	for (int a = 0; a < ATTRIBUTE_COUNT; a++)
	{
		// ...thus we can reset back to defaults even after initializing some
		if (g_ctx.attrs[a].fg >= COLORS || g_ctx.attrs[a].fg < -1
		 || g_ctx.attrs[a].bg >= COLORS || g_ctx.attrs[a].bg < -1)
		{
			// FIXME: we need a 256color default palette that fails gracefully
			//   to something like underlined fields
			app_init_attributes ();
			return;
		}

		init_pair (a + 1, g_ctx.attrs[a].fg, g_ctx.attrs[a].bg);
		g_ctx.attrs[a].attrs |= COLOR_PAIR (a + 1);
	}
}

static void
app_free_context (void)
{
	config_free (&g_ctx.config);
	poller_free (&g_ctx.poller);

	free (g_ctx.marks);
	str_free (&g_ctx.mark_strings);

	for (size_t i = 0; i < g_ctx.marks_by_offset_len; i++)
		free (g_ctx.marks_by_offset[i].marks);
	free (g_ctx.marks_by_offset);

	free (g_ctx.message);

	free (g_ctx.filename);
	free (g_ctx.data);

	if (g_ctx.tk)
		termo_destroy (g_ctx.tk);
}

static void
app_quit (void)
{
	g_ctx.quitting = true;
	g_ctx.polling = false;
}

static bool
app_is_character_in_locale (ucs4_t ch)
{
	// Avoid the overhead joined with calling iconv() for all characters.
	if (g_ctx.locale_is_utf8)
		return true;

	// The library really creates a new conversion object every single time
	// and doesn't provide any smarter APIs.  Luckily, most users use UTF-8.
	size_t len;
	char *tmp = u32_conv_to_encoding (locale_charset (), iconveh_error,
		&ch, 1, NULL, NULL, &len);
	if (!tmp)
		return false;
	free (tmp);
	return true;
}

// --- Field marking -----------------------------------------------------------

/// Find the "marks_by_offset" object covering the offset (if any)
static ssize_t
app_find_marks (int64_t offset)
{
	ssize_t min = 0, end = g_ctx.marks_by_offset_len;
	while (min < end)
	{
		ssize_t mid = min + (end - min) / 2;
		if (offset >= g_ctx.marks_by_offset[mid].offset)
			min = mid + 1;
		else
			end = mid;
	}
	return min - 1;
}

static struct marks_by_offset *
app_marks_at_offset (int64_t offset)
{
	ssize_t i = app_find_marks (offset);
	if (i < 0 || (size_t) i >= g_ctx.marks_by_offset_len)
		return NULL;

	struct marks_by_offset *marks = &g_ctx.marks_by_offset[i];
	if (marks->offset > offset)
		return NULL;
	return marks;
}

static int
app_mark_cmp (const void *first, const void *second)
{
	const struct mark *a = first, *b = second;
	// This ordering is pretty much arbitrary, seemed to make sense
	if (a->offset < b->offset) return -1;
	if (a->offset > b->offset) return  1;
	if (a->len    < b->len)    return  1;
	if (a->len    > b->len)    return -1;
	return 0;
}

static void
app_flatten_marks (void)
{
	qsort (g_ctx.marks, g_ctx.marks_len, sizeof *g_ctx.marks, app_mark_cmp);
	if (!g_ctx.marks_len)
		return;

	ARRAY (struct mark *, current)
	ARRAY_INIT (current);
	int current_color = 0;

	struct mark *next = g_ctx.marks;
	struct mark *end = next + g_ctx.marks_len;
	while (current_len || next < end)
	{
		// Find the closest offset at which marks change
		int64_t closest = g_ctx.data_offset + g_ctx.data_len;
		if (next < end)
			closest = next->offset;
		for (size_t i = 0; i < current_len; i++)
			closest = MIN (closest, current[i]->offset + current[i]->len);

		// Remove from "current" marks that have ended
		for (size_t i = 0; i < current_len; i++)
		{
			if (closest == current[i]->offset + current[i]->len)
				memmove (current + i, current + i + 1,
					(--current_len - i) * sizeof *current);
		}

		// Add any new marks at "closest"
		while (next < end && next->offset == closest)
		{
			ARRAY_RESERVE (current, 1);
			current[current_len++] = next++;
		}

		// Save marks at that offset to be used by rendering
		struct mark **marks = NULL;
		int color = -1;

		if (current_len)
		{
			marks = memcpy (xcalloc (sizeof *marks, current_len + 1),
				current, sizeof *marks * current_len);

			color = ATTRIBUTE_C1 + current_color++;
			current_color %= 4;
		}

		ARRAY_RESERVE (g_ctx.marks_by_offset, 1);
		g_ctx.marks_by_offset[g_ctx.marks_by_offset_len++] =
			(struct marks_by_offset) { closest, marks, color };
	}
	free (current);
}

// --- Rendering ---------------------------------------------------------------

static void
app_invalidate (void)
{
	poller_idle_set (&g_ctx.refresh_event);
}

static void
app_flush_buffer (struct row_buffer *buf, int width, chtype attrs)
{
	row_buffer_align (buf, width, attrs);
	row_buffer_flush (buf);
	row_buffer_free (buf);
}

/// Write the given UTF-8 string padded with spaces.
/// @param[in] attrs  Text attributes for the text, including padding.
static void
app_write_line (const char *str, chtype attrs)
{
	struct row_buffer buf;
	row_buffer_init (&buf);
	row_buffer_append (&buf, str, attrs);
	app_flush_buffer (&buf, COLS, attrs);
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static int
app_visible_rows (void)
{
	return MAX (0, LINES - 1 /* bar */ - 3 /* decoder */ - !!g_ctx.message);
}

static void
app_make_row (struct row_buffer *buf, int64_t addr, int attrs)
{
	char *row_addr_str = xstrdup_printf ("%08" PRIx64, addr);
	row_buffer_append (buf, row_addr_str, attrs);
	free (row_addr_str);

	struct str ascii;
	str_init (&ascii);
	str_append (&ascii, "  ");

	int64_t end_addr = g_ctx.data_offset + g_ctx.data_len;
	for (int x = 0; x < ROW_SIZE; x++)
	{
		if (x % 8 == 0) row_buffer_append (buf, " ", attrs);
		if (x % 2 == 0) row_buffer_append (buf, " ", attrs);

		int64_t cell_addr = addr + x;
		if (cell_addr < g_ctx.data_offset
		 || cell_addr >= end_addr)
		{
			row_buffer_append (buf, "  ", attrs);
			str_append_c (&ascii, ' ');
		}
		else
		{
			int cell_attrs = attrs;
			struct marks_by_offset *marks = app_marks_at_offset (cell_addr);
			if (marks && marks->color >= 0)
				cell_attrs = g_ctx.attrs[marks->color].attrs;

			if (cell_addr >= g_ctx.view_cursor
			 && cell_addr <  g_ctx.view_cursor + 8)
				cell_attrs |= A_UNDERLINE;

			uint8_t cell = g_ctx.data[cell_addr - g_ctx.data_offset];
			char *hex = xstrdup_printf ("%02x", cell);
			row_buffer_append (buf, hex, cell_attrs);
			free (hex);

			str_append_c (&ascii, (cell >= 32 && cell < 127) ? cell : '.');
		}
	}
	row_buffer_append (buf, ascii.str, attrs);
	str_free (&ascii);
}

static void
app_draw_view (void)
{
	move (0, 0);

	int64_t end_addr = g_ctx.data_offset + g_ctx.data_len;
	for (int y = 0; y < app_visible_rows (); y++)
	{
		int64_t addr = g_ctx.view_top + y * ROW_SIZE;
		if (addr >= end_addr)
			break;

		int attrs = (addr / ROW_SIZE & 1) ? APP_ATTR (ODD) : APP_ATTR (EVEN);

		struct row_buffer buf;
		row_buffer_init (&buf);
		app_make_row (&buf, addr, attrs);
		app_flush_buffer (&buf, COLS, attrs);
	}
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static void
app_draw_info (void)
{
	const struct marks_by_offset *marks;
	if (!(marks = app_marks_at_offset (g_ctx.view_cursor)))
		return;

	int x_offset = 70;
	struct mark **iter = marks->marks;
	for (int y = 0; y < app_visible_rows (); y++)
	{
		struct mark *mark;
		if (!iter || !(mark = *iter++))
			break;

		struct row_buffer buf;
		row_buffer_init (&buf);
		row_buffer_append (&buf,
			g_ctx.mark_strings.str + mark->description, 0);

		move (y, x_offset);
		app_flush_buffer (&buf, COLS - x_offset, 0);
	}
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static uint64_t
app_decode (const uint8_t *p, size_t len, enum endianity endianity)
{
	uint64_t val = 0;
	if (endianity == ENDIANITY_BE)
		for (size_t i = 0; i < len; i++)
			val = val << 8 | (uint64_t) p[i];
	else
		while (len--)
			val = val << 8 | (uint64_t) p[len];
	return val;
}

static void
app_write_footer (struct row_buffer *b, char id, int len, const char *fmt, ...)
	ATTRIBUTE_PRINTF (4, 5);

static void
app_footer_field (struct row_buffer *b, char id, int len, const char *fmt, ...)
{
	const char *coding;
	if (len <= 1)
		coding = "";
	else if (g_ctx.endianity == ENDIANITY_LE)
		coding = "le";
	else if (g_ctx.endianity == ENDIANITY_BE)
		coding = "be";

	char *key = xstrdup_printf ("%c%d%s", id, len * 8, coding);
	row_buffer_append (b, key, APP_ATTR (FOOTER_HL));
	free (key);

	struct str value;
	str_init (&value);

	va_list ap;
	va_start (ap, fmt);
	str_append_vprintf (&value, fmt, ap);
	va_end (ap);

	row_buffer_append (b, value.str, APP_ATTR (FOOTER));
	str_free (&value);
}

static void
app_draw_footer (void)
{
	move (app_visible_rows (), 0);

	struct row_buffer buf;
	row_buffer_init (&buf);
	row_buffer_append (&buf, APP_TITLE, APP_ATTR (BAR));

	if (g_ctx.filename)
	{
		row_buffer_append (&buf, "  ", APP_ATTR (BAR));
		char *filename = (char *) u8_strconv_from_locale (g_ctx.filename);
		row_buffer_append (&buf, filename, APP_ATTR (BAR_HL));
		free (filename);
	}

	struct str right;
	str_init (&right);
	str_append_printf (&right, "  %08" PRIx64, g_ctx.view_cursor);
	str_append (&right, g_ctx.endianity == ENDIANITY_LE ? "  LE  " : "  BE  ");

	int64_t top = g_ctx.view_top;
	int64_t bot = g_ctx.view_top + app_visible_rows () * ROW_SIZE;
	if (top <= g_ctx.data_offset
	 && bot >= g_ctx.data_offset + g_ctx.data_len)
		str_append (&right, "All");
	else if (top <= g_ctx.data_offset)
		str_append (&right, "Top");
	else if (bot >= g_ctx.data_offset + g_ctx.data_len)
		str_append (&right, "Bot");
	else
	{
		int64_t end_addr = g_ctx.data_offset + g_ctx.data_len;
		int64_t cur = g_ctx.view_top / ROW_SIZE;
		int64_t max = (end_addr - 1) / ROW_SIZE - app_visible_rows () + 1;

		cur -= g_ctx.data_offset / ROW_SIZE;
		max -= g_ctx.data_offset / ROW_SIZE;
		str_append_printf (&right, "%2d%%", (int) (100 * cur / max));
	}

	row_buffer_align (&buf, COLS - right.len, APP_ATTR (BAR));
	row_buffer_append (&buf, right.str, APP_ATTR (BAR));
	app_flush_buffer (&buf, COLS, APP_ATTR (BAR));

	int64_t end_addr = g_ctx.data_offset + g_ctx.data_len;
	if (g_ctx.view_cursor < g_ctx.data_offset
	 || g_ctx.view_cursor >= end_addr)
		return;

	int64_t len = end_addr - g_ctx.view_cursor;
	uint8_t *p = g_ctx.data + (g_ctx.view_cursor - g_ctx.data_offset);

	struct row_buffer x; row_buffer_init (&x);
	struct row_buffer u; row_buffer_init (&u);
	struct row_buffer s; row_buffer_init (&s);

	if (len >= 1)
	{
		app_footer_field (&x, 'x', 1, "   %02x  ", p[0]);
		app_footer_field (&u, 'u', 1, " %4u  ", p[0]);
		app_footer_field (&s, 's', 1, " %4d  ", (int8_t) p[0]);
	}
	if (len >= 2)
	{
		uint16_t val = app_decode (p, 2, g_ctx.endianity);
		app_footer_field (&x, 'x', 2, "   %04x  ", val);
		app_footer_field (&u, 'u', 2, " %6u  ", val);
		app_footer_field (&s, 's', 2, " %6d  ", (int16_t) val);
	}
	if (len >= 4)
	{
		uint32_t val = app_decode (p, 4, g_ctx.endianity);
		app_footer_field (&x, 'x', 4, "    %08x  ", val);
		app_footer_field (&u, 'u', 4, " %11u  ", val);
		app_footer_field (&s, 's', 4, " %11d  ", (int32_t) val);
	}
	if (len >= 8)
	{
		uint64_t val = app_decode (p, 8, g_ctx.endianity);
		app_footer_field (&x, 'x', 8, "     %016" PRIx64, val);
		app_footer_field (&u, 'u', 8, " %20" PRIu64, val);
		app_footer_field (&s, 's', 8, " %20" PRId64, (int64_t) val);
	}

	app_flush_buffer (&x, COLS, APP_ATTR (FOOTER));
	app_flush_buffer (&u, COLS, APP_ATTR (FOOTER));
	app_flush_buffer (&s, COLS, APP_ATTR (FOOTER));

	if (g_ctx.message)
		app_write_line (g_ctx.message, g_ctx.attrs[g_ctx.message_attr].attrs);
}

static void
app_on_refresh (void *user_data)
{
	(void) user_data;
	poller_idle_reset (&g_ctx.refresh_event);

	erase ();
	app_draw_view ();
	app_draw_info ();
	app_draw_footer ();

	int64_t diff = g_ctx.view_cursor - g_ctx.view_top;
	int64_t y = diff / ROW_SIZE;
	int64_t x = diff % ROW_SIZE;
	if (y >= 0 && y < app_visible_rows ())
	{
		curs_set (1);
		move (y, 10 + x*2 + g_ctx.view_skip_nibble + x/8 + x/2);
	}
	else
		curs_set (0);

	refresh ();
}

// --- Lua ---------------------------------------------------------------------

#ifdef HAVE_LUA

static void *
app_lua_alloc (void *ud, void *ptr, size_t o_size, size_t n_size)
{
	(void) ud;
	(void) o_size;

	if (n_size)
		return realloc (ptr, n_size);

	free (ptr);
	return NULL;
}

static int
app_lua_panic (lua_State *L)
{
	// XXX: we might be able to do something better
	print_fatal ("Lua panicked: %s", lua_tostring (L, -1));
	lua_close (L);
	exit (EXIT_FAILURE);
	return 0;
}

static bool
app_lua_getfield (lua_State *L, int idx, const char *name,
	int expected, bool optional)
{
	int found = lua_getfield (L, idx, name);
	if (found == expected)
		return true;
	if (optional && found == LUA_TNIL)
		return false;

	const char *message = optional
		? "invalid field \"%s\" (found: %s, expected: %s or nil)"
		: "invalid or missing field \"%s\" (found: %s, expected: %s)";
	return luaL_error (L, message, name,
		lua_typename (L, found), lua_typename (L, expected));
}

static int
app_lua_error_handler (lua_State *L)
{
	luaL_traceback (L, L, luaL_checkstring (L, 1), 1);
	return 1;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

struct app_lua_coder
{
	int ref_detect;                     ///< Reference to the "detect" method
	int ref_decode;                     ///< Reference to the "decode" method
};

static void
app_lua_coder_free (void *coder)
{
	struct app_lua_coder *self = coder;
	luaL_unref (g_ctx.L, LUA_REGISTRYINDEX, self->ref_decode);
	luaL_unref (g_ctx.L, LUA_REGISTRYINDEX, self->ref_detect);
}

static int
app_lua_register (lua_State *L)
{
	luaL_checktype (L, 1, LUA_TTABLE);

	(void) app_lua_getfield (L, 1, "type",   LUA_TSTRING,   false);
	const char *type = lua_tostring (L, -1);
	if (str_map_find (&g_ctx.coders, type))
		luaL_error (L, "a coder has already been registered for `%s'", type);

	(void) app_lua_getfield (L, 1, "detect", LUA_TFUNCTION, true);
	(void) app_lua_getfield (L, 1, "decode", LUA_TFUNCTION, false);

	struct app_lua_coder *coder = xcalloc (1, sizeof *coder);
	coder->ref_decode = luaL_ref (L, LUA_REGISTRYINDEX);
	coder->ref_detect = luaL_ref (L, LUA_REGISTRYINDEX);
	str_map_set (&g_ctx.coders, type, coder);
	return 0;
}

static luaL_Reg app_lua_library[] =
{
	{ "register", app_lua_register },
	{ NULL,       NULL             }
};

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

#define XLUA_CHUNK_METATABLE "chunk"

struct app_lua_chunk
{
	int64_t offset;                     ///< Offset from start of file
	int64_t len;                        ///< Length of the sequence

	int64_t position;                   ///< Read position in the sequence
	enum endianity endianity;           ///< Read endianity
};

static struct app_lua_chunk *
app_lua_chunk_new (lua_State *L)
{
	struct app_lua_chunk *chunk = lua_newuserdata (L, sizeof *chunk);
	luaL_setmetatable (L, XLUA_CHUNK_METATABLE);
	memset (chunk, 0, sizeof *chunk);
	return chunk;
}

static int
app_lua_chunk_len (lua_State *L)
{
	struct app_lua_chunk *self = luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	lua_pushinteger (L, self->len);
	return 0;
}

/// Create a new subchunk following Lua's string.sub() semantics.
/// An implication is that it is not possible to go extend a chunk's bounds.
static int
app_lua_chunk_call (lua_State *L)
{
	struct app_lua_chunk *self = luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	lua_Integer start = luaL_optinteger (L, 2,  1);
	lua_Integer end   = luaL_optinteger (L, 3, -1);

	if (start < 0) start += self->len + 1;
	if (end   < 0) end   += self->len + 1;

	start = MAX (start, 1);
	end = MIN (end, self->len);

	struct app_lua_chunk *clone = app_lua_chunk_new (L);
	clone->position = 0;
	clone->endianity = self->endianity;
	if (start > end)
	{
		// "start" can be too high and "end" can be too low;
		// the length is zero, so the offset doesn't matter much anyway
		clone->offset = self->offset;
		clone->len = 0;
	}
	else
	{
		clone->offset = self->offset + start - 1;
		clone->len = end - start + 1;
	}
	return 1;
}

static int
app_lua_chunk_index (lua_State *L)
{
	struct app_lua_chunk *self = luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	const char *key = luaL_checkstring (L, 2);
	if (luaL_getmetafield (L, 1, key))
		return 1;

	if (!strcmp (key, "offset"))
		lua_pushinteger (L, self->offset);
	else if (!strcmp (key, "endianity"))
		lua_pushstring (L, self->endianity == ENDIANITY_LE ? "le" : "be");
	else if (!strcmp (key, "position"))
		lua_pushinteger (L, self->position + 1);
	else if (!strcmp (key, "eof"))
		lua_pushboolean (L, self->position >= self->len);
	else
		return luaL_argerror (L, 2, "not a readable property");
	return 1;
}

static int
app_lua_chunk_newindex (lua_State *L)
{
	struct app_lua_chunk *self = luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	const char *key = luaL_checkstring (L, 2);
	if (!strcmp (key, "endianity"))
	{
		// Needs to be in the enum order
		const char *options[] = { "le", "be" };
		self->endianity = luaL_checkoption (L, 3, options[0], options);
	}
	else if (!strcmp (key, "position"))
	{
		lua_Integer position = luaL_checkinteger (L, 3) - 1;
		if (position < 1 || position > self->len + 1)
			return luaL_error (L, "position out of range: %" PRId64, position);
		self->position = position - 1;
	}
	else
		return luaL_argerror (L, 2, "not a writable property");
	return 0;
}

static void
app_lua_mark (int64_t offset, int64_t len, const char *desc)
{
	ARRAY_RESERVE (g_ctx.marks, 1);
	g_ctx.marks[g_ctx.marks_len++] =
		(struct mark) { offset, len, g_ctx.mark_strings.len };

	str_append (&g_ctx.mark_strings, desc);
	str_append_c (&g_ctx.mark_strings, 0);
}

static int
app_lua_chunk_mark (lua_State *L)
{
	struct app_lua_chunk *self = luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	app_lua_mark (self->offset, self->len, luaL_checkstring (L, 2));
	return 0;
}

/// Try to detect any registered type in the data and return its name
static int
app_lua_chunk_identify (lua_State *L)
{
	(void) luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);

	struct str_map_iter iter;
	str_map_iter_init (&iter, &g_ctx.coders);
	struct app_lua_coder *coder;
	while ((coder = str_map_iter_next (&iter)))
	{
		lua_rawgeti (L, LUA_REGISTRYINDEX, coder->ref_detect);

		// Clone the chunk first to reset its read position
		lua_pushcfunction (L, app_lua_chunk_call);
		lua_pushvalue (L, 1);
		lua_call (L, 1, 1);

		lua_call (L, 1, 1);
		if (lua_toboolean (L, -1))
		{
			lua_pushstring (L, iter.link->key);
			return 1;
		}
		lua_pop (L, 1);
	}
	return 0;
}

static int
app_lua_chunk_decode (lua_State *L)
{
	(void) luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	const char *type = luaL_optstring (L, 2, NULL);
	// TODO: further arguments should be passed to the decoding function

	if (!type)
	{
		lua_pushcfunction (L, app_lua_chunk_identify);
		lua_pushvalue (L, 1);
		lua_call (L, 1, 1);
		type = lua_tostring (L, -1);
	}
	// Can't identify -> can't decode, nothing to do here
	if (!type)
		return 0;

	// While we could call "detect" here, just to be sure, some kinds may not
	// even be detectable and it's better to leave it up to the plugin

	struct app_lua_coder *coder = str_map_find (&g_ctx.coders, type);
	if (!coder)
		return luaL_error (L, "unknown type: %s", type);

	lua_rawgeti (L, LUA_REGISTRYINDEX, coder->ref_decode);
	lua_pushvalue (L, 1);
	// TODO: the chunk could remember the name of the coder and prepend it
	//   to all marks set from the callback; then reset it back to NULL
	lua_call (L, 1, 0);
	return 0;
}

static int
app_lua_chunk_read (lua_State *L)
{
	struct app_lua_chunk *self = luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	lua_Integer len = luaL_checkinteger (L, 2);
	if (len < 0)
		return luaL_argerror (L, 2, "invalid read length");

	int64_t start = self->offset + self->position;
	// XXX: or just return a shorter string in this case?
	if (start + len > g_ctx.data_offset + g_ctx.data_len)
		return luaL_argerror (L, 2, "chunk is too short");

	lua_pushlstring (L, (char *) g_ctx.data + (start - g_ctx.data_offset), len);
	self->position += len;
	return 1;
}

/// Mark a field that has just been read from the chunk and advance position:
///  - the second argument, if present, is a simple format string for marking;
///  - the third argument, if present, is a filtering function.
///
/// I am aware of how ugly the implicit "string.format" is.  Convenience wins.
static void
app_lua_chunk_finish_read
	(lua_State *L, struct app_lua_chunk *self, int64_t len)
{
	int n_args = lua_gettop (L) - 1;
	if (n_args < 2)
		return;

	// Prepare <string.format>, <format>, <value>
	lua_rawgeti (L, LUA_REGISTRYINDEX, g_ctx.ref_format);
	lua_pushvalue (L, 2);

	int pre_filter_top = lua_gettop (L);
	lua_pushvalue (L, -3);

	// Transform the value if a filtering function is provided
	if (n_args >= 3)
	{
		lua_pushvalue (L, 3);
		lua_insert (L, -2);
		lua_call (L, 1, LUA_MULTRET);
		int n_ret = lua_gettop (L) - pre_filter_top;

		// When no value has been returned, keep the old one
		if (n_ret < 1)
			lua_pushvalue (L, pre_filter_top - 2);

		// Forward multiple return values to "string.format"
		if (n_ret > 1)
		{
			lua_pushvalue (L, pre_filter_top - 1);
			lua_insert (L, -n_ret - 1);
			lua_call (L, n_ret, 1);
		}
	}

	lua_call (L, 2, 1);
	app_lua_mark (self->offset + self->position, len, lua_tostring (L, -1));
	self->position += len;
	lua_pop (L, 1);
}

static int
app_lua_chunk_cstring (lua_State *L)
{
	struct app_lua_chunk *self = luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);
	void *s = g_ctx.data + (self->offset - g_ctx.data_offset) + self->position;

	void *nil;
	if (!(nil = memchr (s, '\0', self->len - self->position)))
		return luaL_error (L, "unexpected EOF");

	lua_pushlstring (L, s, nil - s);
	app_lua_chunk_finish_read (L, self, nil - s + 1);
	return 1;
}

/// Decode "len" bytes as a number starting at the current position in "self"
static uint64_t
app_lua_chunk_decode_int (lua_State *L, struct app_lua_chunk *self, size_t len)
{
	if (self->position + (int64_t) len > self->len)
		return luaL_error (L, "unexpected EOF");

	void *s = g_ctx.data + (self->offset - g_ctx.data_offset) + self->position;
	return app_decode (s, len, self->endianity);
}

#define APP_LUA_CHUNK_INT(name, type)                                          \
	static int                                                                 \
	app_lua_chunk_ ## name (lua_State *L)                                      \
	{                                                                          \
		struct app_lua_chunk *self =                                           \
			luaL_checkudata (L, 1, XLUA_CHUNK_METATABLE);                      \
		type v = app_lua_chunk_decode_int (L, self, sizeof v);                 \
		lua_pushinteger (L, v);                                                \
		app_lua_chunk_finish_read (L, self, sizeof v);                         \
		return 1;                                                              \
	}

APP_LUA_CHUNK_INT (u8,  uint8_t)  APP_LUA_CHUNK_INT (s8,  int8_t)
APP_LUA_CHUNK_INT (u16, uint16_t) APP_LUA_CHUNK_INT (s16, int16_t)
APP_LUA_CHUNK_INT (u32, uint32_t) APP_LUA_CHUNK_INT (s32, int32_t)
APP_LUA_CHUNK_INT (u64, uint64_t) APP_LUA_CHUNK_INT (s64, int64_t)

static luaL_Reg app_lua_chunk_table[] =
{
	{ "__len",      app_lua_chunk_len      },
	{ "__call",     app_lua_chunk_call     },
	{ "__index",    app_lua_chunk_index    },
	{ "__newindex", app_lua_chunk_newindex },
	{ "mark",       app_lua_chunk_mark     },
	{ "identify",   app_lua_chunk_identify },
	{ "decode",     app_lua_chunk_decode   },

	{ "read",       app_lua_chunk_read     },
	{ "cstring",    app_lua_chunk_cstring  },
	{ "u8",         app_lua_chunk_u8       },
	{ "s8",         app_lua_chunk_s8       },
	{ "u16",        app_lua_chunk_u16      },
	{ "s16",        app_lua_chunk_s16      },
	{ "u32",        app_lua_chunk_u32      },
	{ "s32",        app_lua_chunk_s32      },
	{ "u64",        app_lua_chunk_u64      },
	{ "s64",        app_lua_chunk_s64      },
	{ NULL,         NULL                   }
};

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static void
app_lua_load_plugins (const char *plugin_dir)
{
	DIR *dir;
	if (!(dir = opendir (plugin_dir)))
	{
		if (errno != ENOENT)
			print_error ("cannot open directory `%s': %s",
				plugin_dir, strerror (errno));
		return;
	}

	struct dirent *iter;
	while ((errno = 0, iter = readdir (dir)))
	{
		const char *dot = strrchr (iter->d_name, '.');
		if (!dot || strcmp (dot, ".lua"))
			continue;

		char *path = xstrdup_printf ("%s/%s", plugin_dir, iter->d_name);
		lua_pushcfunction (g_ctx.L, app_lua_error_handler);
		if (luaL_loadfile (g_ctx.L, path)
		 || lua_pcall (g_ctx.L, 0, 0, -2))
			exit_fatal ("Lua: %s", lua_tostring (g_ctx.L, -1));
		lua_pop (g_ctx.L, 1);
		free (path);
	}
	if (errno)
		exit_fatal ("readdir: %s", strerror (errno));
	closedir (dir);
}

static void
app_lua_init (void)
{
	if (!(g_ctx.L = lua_newstate (app_lua_alloc, NULL)))
		exit_fatal ("Lua initialization failed");

	str_map_init (&g_ctx.coders);
	g_ctx.coders.free = app_lua_coder_free;

	lua_atpanic (g_ctx.L, app_lua_panic);
	luaL_openlibs (g_ctx.L);
	luaL_checkversion (g_ctx.L);

	// I don't want to reimplement this and the C function is not exported
	hard_assert (lua_getglobal (g_ctx.L, LUA_STRLIBNAME));
	hard_assert (lua_getfield (g_ctx.L, -1, "format"));
	g_ctx.ref_format = luaL_ref (g_ctx.L, LUA_REGISTRYINDEX);

	luaL_newlib (g_ctx.L, app_lua_library);
	lua_setglobal (g_ctx.L, PROGRAM_NAME);

	luaL_newmetatable (g_ctx.L, XLUA_CHUNK_METATABLE);
	luaL_setfuncs (g_ctx.L, app_lua_chunk_table, 0);
	lua_pop (g_ctx.L, 1);

	struct str_vector v;
	str_vector_init (&v);
	get_xdg_data_dirs (&v);
	for (size_t i = 0; i < v.len; i++)
	{
		char *path = xstrdup_printf
			("%s/%s", v.vector[i], PROGRAM_NAME "/plugins");
		app_lua_load_plugins (path);
		free (path);
	}
	str_vector_free (&v);
}

#endif // HAVE_LUA

// --- Actions -----------------------------------------------------------------

/// Checks what items are visible and returns if fixes were needed
static bool
app_fix_view_range (void)
{
	int64_t data_view_start = g_ctx.data_offset / ROW_SIZE * ROW_SIZE;
	if (g_ctx.view_top < data_view_start)
	{
		g_ctx.view_top = data_view_start;
		app_invalidate ();
		return false;
	}

	// If the contents are at least as long as the screen, always fill it
	int64_t last_byte = g_ctx.data_offset + g_ctx.data_len - 1;
	int64_t max_view_top =
		(last_byte / ROW_SIZE - app_visible_rows () + 1) * ROW_SIZE;
	// But don't let that suggest a negative offset
	max_view_top = MAX (max_view_top, 0);

	if (g_ctx.view_top > max_view_top)
	{
		g_ctx.view_top = max_view_top;
		app_invalidate ();
		return false;
	}
	return true;
}

/// Scroll down (positive) or up (negative) @a n items
static bool
app_scroll (int n)
{
	g_ctx.view_top += n * ROW_SIZE;
	app_invalidate ();
	return app_fix_view_range ();
}

static void
app_ensure_selection_visible (void)
{
	int too_high = g_ctx.view_top / ROW_SIZE - g_ctx.view_cursor / ROW_SIZE;
	if (too_high > 0)
		app_scroll (-too_high);

	int too_low = g_ctx.view_cursor / ROW_SIZE - g_ctx.view_top / ROW_SIZE
		- app_visible_rows () + 1;
	if (too_low > 0)
		app_scroll (too_low);
}

static bool
app_move_cursor_by_rows (int diff)
{
	// TODO: disallow partial up/down movement
	int64_t fixed = g_ctx.view_cursor += diff * ROW_SIZE;
	fixed = MAX (fixed, g_ctx.data_offset);
	fixed = MIN (fixed, g_ctx.data_offset + g_ctx.data_len - 1);

	bool result = g_ctx.view_cursor == fixed;
	g_ctx.view_cursor = fixed;
	app_invalidate ();

	app_ensure_selection_visible ();
	return result;
}

// --- User input handling -----------------------------------------------------

enum action
{
	ACTION_NONE, ACTION_QUIT, ACTION_REDRAW, ACTION_TOGGLE_ENDIANITY,

	ACTION_SCROLL_UP,   ACTION_GOTO_TOP,    ACTION_GOTO_PAGE_PREVIOUS,
	ACTION_SCROLL_DOWN, ACTION_GOTO_BOTTOM, ACTION_GOTO_PAGE_NEXT,

	ACTION_UP, ACTION_DOWN, ACTION_LEFT, ACTION_RIGHT,

	ACTION_COUNT
};

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static bool
app_process_action (enum action action)
{
	switch (action)
	{
		// XXX: these should rather be parametrized
	case ACTION_SCROLL_UP:   app_scroll (-1); break;
	case ACTION_SCROLL_DOWN: app_scroll  (1); break;

	case ACTION_GOTO_TOP:
		g_ctx.view_cursor = g_ctx.data_offset;
		g_ctx.view_skip_nibble = false;
		app_ensure_selection_visible ();
		app_invalidate ();
		break;
	case ACTION_GOTO_BOTTOM:
		if (!g_ctx.data_len)
			return false;

		g_ctx.view_cursor = g_ctx.data_offset + g_ctx.data_len - 1;
		g_ctx.view_skip_nibble = false;
		app_ensure_selection_visible ();
		app_invalidate ();
		break;

	case ACTION_GOTO_PAGE_PREVIOUS:
		app_scroll (-app_visible_rows ());
		app_move_cursor_by_rows (-app_visible_rows ());
		break;
	case ACTION_GOTO_PAGE_NEXT:
		app_scroll (app_visible_rows ());
		app_move_cursor_by_rows (app_visible_rows ());
		break;

	case ACTION_UP:   app_move_cursor_by_rows (-1); break;
	case ACTION_DOWN: app_move_cursor_by_rows  (1); break;

	case ACTION_LEFT:
		if (g_ctx.view_skip_nibble)
			g_ctx.view_skip_nibble = false;
		else
		{
			if (g_ctx.view_cursor <= g_ctx.data_offset)
				return false;

			g_ctx.view_skip_nibble = true;
			g_ctx.view_cursor--;
			app_ensure_selection_visible ();
		}
		app_invalidate ();
		break;
	case ACTION_RIGHT:
		if (!g_ctx.view_skip_nibble)
			g_ctx.view_skip_nibble = true;
		else
		{
			if (g_ctx.view_cursor >= g_ctx.data_offset + g_ctx.data_len - 1)
				return false;

			g_ctx.view_skip_nibble = false;
			g_ctx.view_cursor++;
			app_ensure_selection_visible ();
		}
		app_invalidate ();
		break;

	case ACTION_QUIT:
		app_quit ();
	case ACTION_NONE:
		break;
	case ACTION_REDRAW:
		clear ();
		app_invalidate ();
		break;

	case ACTION_TOGGLE_ENDIANITY:
		g_ctx.endianity = (g_ctx.endianity == ENDIANITY_LE)
			? ENDIANITY_BE : ENDIANITY_LE;
		app_invalidate ();
		break;
	default:
		return false;
	}
	return true;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static bool
app_process_left_mouse_click (int line, int column)
{
	if (line < 0)
		return false;

	if (line == app_visible_rows ())
	{
		if (column <  COLS - 7
		 || column >= COLS - 5)
			return false;
		return app_process_action (ACTION_TOGGLE_ENDIANITY);
	}
	else if (line < app_visible_rows ())
	{
		// TODO: employ strict checking here before the autofix
		int offset;
		if (column >= 10 && column < 50)
		{
			offset = column - 10;
			offset -= offset/5 + offset/21;
			g_ctx.view_skip_nibble = offset % 2;
			offset /= 2;
		}
		else if (column >= 52 && column < 68)
		{
			offset = column - 52;
			g_ctx.view_skip_nibble = false;
		}
		else
			return false;

		g_ctx.view_cursor = g_ctx.view_top + line * ROW_SIZE + offset;
		return app_move_cursor_by_rows (0);
	}
	return true;
}

static bool
app_process_mouse (termo_mouse_event_t type, int line, int column, int button)
{
	if (type != TERMO_MOUSE_PRESS)
		return true;

	if (button == 1)
		return app_process_left_mouse_click (line, column);
	else if (button == 4)
		return app_process_action (ACTION_SCROLL_UP);
	else if (button == 5)
		return app_process_action (ACTION_SCROLL_DOWN);
	return false;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

static struct binding
{
	const char *key;                    ///< Key definition
	enum action action;                 ///< Action to take
	termo_key_t decoded;                ///< Decoded key definition
}
g_default_bindings[] =
{
	{ "Escape",     ACTION_QUIT,               {}},
	{ "q",          ACTION_QUIT,               {}},
	{ "C-l",        ACTION_REDRAW,             {}},
	{ "Tab",        ACTION_TOGGLE_ENDIANITY,   {}},

	{ "Home",       ACTION_GOTO_TOP,           {}},
	{ "End",        ACTION_GOTO_BOTTOM,        {}},
	{ "M-<",        ACTION_GOTO_TOP,           {}},
	{ "M->",        ACTION_GOTO_BOTTOM,        {}},
	{ "g",          ACTION_GOTO_TOP,           {}},
	{ "G",          ACTION_GOTO_BOTTOM,        {}},
	{ "PageUp",     ACTION_GOTO_PAGE_PREVIOUS, {}},
	{ "PageDown",   ACTION_GOTO_PAGE_NEXT,     {}},
	{ "C-b",        ACTION_GOTO_PAGE_PREVIOUS, {}},
	{ "C-f",        ACTION_GOTO_PAGE_NEXT,     {}},

	{ "Up",         ACTION_UP,                 {}},
	{ "Down",       ACTION_DOWN,               {}},
	{ "Left",       ACTION_LEFT,               {}},
	{ "Right",      ACTION_RIGHT,              {}},
	{ "k",          ACTION_UP,                 {}},
	{ "j",          ACTION_DOWN,               {}},
	{ "h",          ACTION_LEFT,               {}},
	{ "l",          ACTION_RIGHT,              {}},
	{ "C-p",        ACTION_UP,                 {}},
	{ "C-n",        ACTION_DOWN,               {}},

	{ "C-y",        ACTION_SCROLL_UP,          {}},
	{ "C-e",        ACTION_SCROLL_DOWN,        {}},
};

static int
app_binding_cmp (const void *a, const void *b)
{
	return termo_keycmp (g_ctx.tk,
		&((struct binding *) a)->decoded, &((struct binding *) b)->decoded);
}

static void
app_init_bindings (void)
{
	for (size_t i = 0; i < N_ELEMENTS (g_default_bindings); i++)
	{
		struct binding *binding = &g_default_bindings[i];
		hard_assert (!*termo_strpkey_utf8 (g_ctx.tk,
			binding->key, &binding->decoded, TERMO_FORMAT_ALTISMETA));
	}
	qsort (g_default_bindings, N_ELEMENTS (g_default_bindings),
		sizeof *g_default_bindings, app_binding_cmp);
}

static bool
app_process_termo_event (termo_key_t *event)
{
	struct binding dummy = { NULL, 0, *event }, *binding =
		bsearch (&dummy, g_default_bindings, N_ELEMENTS (g_default_bindings),
			sizeof *g_default_bindings, app_binding_cmp);
	if (binding)
		return app_process_action (binding->action);

	// TODO: once we become an editor, use 0-9 a-f to overwrite nibbles
	return false;
}

// --- Signals -----------------------------------------------------------------

static int g_signal_pipe[2];            ///< A pipe used to signal... signals

/// Program termination has been requested by a signal
static volatile sig_atomic_t g_termination_requested;
/// The window has changed in size
static volatile sig_atomic_t g_winch_received;

static void
signals_postpone_handling (char id)
{
	int original_errno = errno;
	if (write (g_signal_pipe[1], &id, 1) == -1)
		soft_assert (errno == EAGAIN);
	errno = original_errno;
}

static void
signals_superhandler (int signum)
{
	switch (signum)
	{
	case SIGWINCH:
		g_winch_received = true;
		signals_postpone_handling ('w');
		break;
	case SIGINT:
	case SIGTERM:
		g_termination_requested = true;
		signals_postpone_handling ('t');
		break;
	default:
		hard_assert (!"unhandled signal");
	}
}

static void
signals_setup_handlers (void)
{
	if (pipe (g_signal_pipe) == -1)
		exit_fatal ("%s: %s", "pipe", strerror (errno));

	set_cloexec (g_signal_pipe[0]);
	set_cloexec (g_signal_pipe[1]);

	// So that the pipe cannot overflow; it would make write() block within
	// the signal handler, which is something we really don't want to happen.
	// The same holds true for read().
	set_blocking (g_signal_pipe[0], false);
	set_blocking (g_signal_pipe[1], false);

	signal (SIGPIPE, SIG_IGN);

	struct sigaction sa;
	sa.sa_flags = SA_RESTART;
	sa.sa_handler = signals_superhandler;
	sigemptyset (&sa.sa_mask);

	if (sigaction (SIGWINCH, &sa, NULL) == -1
	 || sigaction (SIGINT,   &sa, NULL) == -1
	 || sigaction (SIGTERM,  &sa, NULL) == -1)
		exit_fatal ("sigaction: %s", strerror (errno));
}

// --- Initialisation, event handling ------------------------------------------

static void
app_on_tty_readable (const struct pollfd *fd, void *user_data)
{
	(void) user_data;
	if (fd->revents & ~(POLLIN | POLLHUP | POLLERR))
		print_debug ("fd %d: unexpected revents: %d", fd->fd, fd->revents);

	poller_timer_reset (&g_ctx.tk_timer);
	termo_advisereadable (g_ctx.tk);

	termo_key_t event;
	termo_result_t res;
	while ((res = termo_getkey (g_ctx.tk, &event)) == TERMO_RES_KEY)
	{
		int y, x, button;
		termo_mouse_event_t type;
		bool success;
		if (termo_interpret_mouse (g_ctx.tk, &event, &type, &button, &y, &x))
			success = app_process_mouse (type, y, x, button);
		else
			success = app_process_termo_event (&event);

		if (!success)
			beep ();
	}

	if (res == TERMO_RES_AGAIN)
		poller_timer_set (&g_ctx.tk_timer, termo_get_waittime (g_ctx.tk));
	else if (res == TERMO_RES_ERROR || res == TERMO_RES_EOF)
		app_quit ();
}

static void
app_on_key_timer (void *user_data)
{
	(void) user_data;

	termo_key_t event;
	if (termo_getkey_force (g_ctx.tk, &event) == TERMO_RES_KEY)
		if (!app_process_termo_event (&event))
			app_quit ();
}

static void
app_on_signal_pipe_readable (const struct pollfd *fd, void *user_data)
{
	(void) user_data;

	char id = 0;
	(void) read (fd->fd, &id, 1);

	if (g_termination_requested && !g_ctx.quitting)
		app_quit ();

	if (g_winch_received)
	{
		update_curses_terminal_size ();
		app_fix_view_range ();
		app_invalidate ();

		g_winch_received = false;
	}
}

static void
app_log_handler (void *user_data, const char *quote, const char *fmt,
	va_list ap)
{
	// We certainly don't want to end up in a possibly infinite recursion
	static bool in_processing;
	if (in_processing)
		return;

	in_processing = true;

	struct str message;
	str_init (&message);
	str_append (&message, quote);
	str_append_vprintf (&message, fmt, ap);

	// If the standard error output isn't redirected, try our best at showing
	// the message to the user
	if (!isatty (STDERR_FILENO))
		fprintf (stderr, "%s\n", message.str);
	else
	{
		free (g_ctx.message);
		g_ctx.message = xstrdup (message.str);
		g_ctx.message_attr = (intptr_t) user_data;
		app_invalidate ();
	}
	str_free (&message);

	in_processing = false;
}

static void
app_init_poller_events (void)
{
	poller_fd_init (&g_ctx.signal_event, &g_ctx.poller, g_signal_pipe[0]);
	g_ctx.signal_event.dispatcher = app_on_signal_pipe_readable;
	poller_fd_set (&g_ctx.signal_event, POLLIN);

	poller_fd_init (&g_ctx.tty_event, &g_ctx.poller, STDIN_FILENO);
	g_ctx.tty_event.dispatcher = app_on_tty_readable;
	poller_fd_set (&g_ctx.tty_event, POLLIN);

	poller_timer_init (&g_ctx.tk_timer, &g_ctx.poller);
	g_ctx.tk_timer.dispatcher = app_on_key_timer;

	poller_idle_init (&g_ctx.refresh_event, &g_ctx.poller);
	g_ctx.refresh_event.dispatcher = app_on_refresh;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

/// Decode size arguments according to similar rules to those that dd(1) uses;
/// we support octal and hexadecimal numbers but they clash with suffixes
static bool
decode_size (const char *s, int64_t *out)
{
	char *end;
	errno = 0;
	int64_t n = strtol (s, &end, 0);
	if (errno != 0 || end == s || n < 0)
		return false;

	int64_t f = 1;
	switch (*end)
	{
	case 'c': f = 1 <<  0;                               end++;   break;
	case 'w': f = 1 <<  1;                               end++;   break;
	case 'b': f = 1 <<  9;                               end++;   break;

	case 'K': f = 1 << 10; if (*++end == 'B') { f = 1e3; end++; } break;
	case 'M': f = 1 << 20; if (*++end == 'B') { f = 1e6; end++; } break;
	case 'G': f = 1 << 30; if (*++end == 'B') { f = 1e9; end++; } break;
	}
	if (*end || n > INT64_MAX / f)
		return false;

	*out = n * f;
	return true;
}

int
main (int argc, char *argv[])
{
	static const struct opt opts[] =
	{
		{ 'd', "debug", NULL, 0, "run in debug mode" },
		{ 'h', "help", NULL, 0, "display this help and exit" },
		{ 'V', "version", NULL, 0, "output version information and exit" },

		{ 'o', "offset", NULL, 0, "offset within the file" },
		{ 's', "size", NULL, 0, "size limit (1G by default)" },
#ifdef HAVE_LUA
		{ 't', "type", NULL, 0, "force interpretation as the given type" },
#endif // HAVE_LUA
		{ 0, NULL, NULL, 0, NULL }
	};

	struct opt_handler oh;
	opt_handler_init (&oh, argc, argv, opts, "[FILE]", "Hex viewer.");
	int64_t size_limit = 1 << 30;
	const char *forced_type = NULL;

	int c;
	while ((c = opt_handler_get (&oh)) != -1)
	switch (c)
	{
	case 'd':
		g_debug_mode = true;
		break;
	case 'h':
		opt_handler_usage (&oh, stdout);
		exit (EXIT_SUCCESS);
	case 'V':
		printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
		exit (EXIT_SUCCESS);

	case 'o':
		if (!decode_size (optarg, &g_ctx.data_offset))
			exit_fatal ("invalid offset specified");
		break;
	case 's':
		if (!decode_size (optarg, &size_limit))
			exit_fatal ("invalid size limit specified");
		break;
	case 't':
		forced_type = optarg;
		break;
	default:
		print_error ("wrong options");
		opt_handler_usage (&oh, stderr);
		exit (EXIT_FAILURE);
	}

	argc -= optind;
	argv += optind;

#ifdef HAVE_LUA
	// We do it at this questionable location to catch plugin failure before
	// we read potentially hundreds of megabytes of data in
	app_lua_init ();

	if (forced_type && !strcmp (forced_type, "list"))
	{
		struct str_map_iter iter;
		str_map_iter_init (&iter, &g_ctx.coders);
		while (str_map_iter_next (&iter))
			puts (iter.link->key);
		exit (EXIT_SUCCESS);
	}
#endif // HAVE_LUA

	// When no filename is given, read from stdin and replace it with the tty
	int input_fd;
	if (argc == 0)
	{
		if ((input_fd = dup (STDIN_FILENO)) < 0)
			exit_fatal ("cannot read input: %s", strerror (errno));
		close (STDIN_FILENO);
		if (open ("/dev/tty", O_RDWR))
			exit_fatal ("cannot open the terminal: %s", strerror (errno));
	}
	else if (argc == 1)
	{
		g_ctx.filename = xstrdup (argv[0]);
		if (!(input_fd = open (argv[0], O_RDONLY)))
			exit_fatal ("cannot open `%s': %s", argv[0], strerror (errno));
	}
	else
	{
		opt_handler_usage (&oh, stderr);
		exit (EXIT_FAILURE);
	}
	opt_handler_free (&oh);

	// Seek in the file or pipe however we can
	static char seek_buf[8192];
	if (lseek (input_fd, g_ctx.data_offset, SEEK_SET) == (off_t) -1)
		for (uint64_t remaining = g_ctx.data_offset; remaining; )
		{
			ssize_t n_read = read (input_fd,
				seek_buf, MIN (remaining, sizeof seek_buf));
			if (n_read <= 0)
				exit_fatal ("cannot seek: %s", strerror (errno));
			remaining -= n_read;
		}

	// Read up to "size_limit" bytes of data into a buffer
	struct str buf;
	str_init (&buf);

	while (buf.len < (size_t) size_limit)
	{
		str_ensure_space (&buf, 8192);
		ssize_t n_read = read (input_fd, buf.str + buf.len,
			MIN (size_limit - buf.len, buf.alloc - buf.len));
		if (!n_read)
			break;
		if (n_read == -1)
			exit_fatal ("cannot read input: %s", strerror (errno));
		buf.len += n_read;
	}

	g_ctx.data = (uint8_t *) buf.str;
	g_ctx.data_len = buf.len;

	g_ctx.view_top = g_ctx.data_offset / ROW_SIZE * ROW_SIZE;
	g_ctx.view_cursor = g_ctx.data_offset;

	// We only need to convert to and from the terminal encoding
	if (!setlocale (LC_CTYPE, ""))
		print_warning ("failed to set the locale");

	app_init_context ();
#ifdef HAVE_LUA
	// TODO: eventually we should do this in a separate thread after load
	//   as it may take a long time (-> responsivity) and once we allow the user
	//   to edit the file, each change will need a background rescan
	lua_pushcfunction (g_ctx.L, app_lua_error_handler);
	lua_pushcfunction (g_ctx.L, app_lua_chunk_decode);

	struct app_lua_chunk *chunk = app_lua_chunk_new (g_ctx.L);
	chunk->offset = g_ctx.data_offset;
	chunk->len = g_ctx.data_len;

	if (forced_type)
		lua_pushstring (g_ctx.L, forced_type);
	else
		lua_pushnil (g_ctx.L);
	if (lua_pcall (g_ctx.L, 2, 0, -4))
		exit_fatal ("Lua: decoding failed: %s", lua_tostring (g_ctx.L, -1));

	lua_pop (g_ctx.L, 1);
#endif // HAVE_LUA
	app_flatten_marks ();

	app_load_configuration ();
	app_init_terminal ();
	signals_setup_handlers ();
	app_init_poller_events ();
	app_invalidate ();
	app_init_bindings ();

	// Redirect all messages from liberty so that they don't disrupt display
	g_log_message_real = app_log_handler;

	g_ctx.polling = true;
	while (g_ctx.polling)
		poller_run (&g_ctx.poller);

	endwin ();
	g_log_message_real = log_message_stdio;
	app_free_context ();

#ifdef HAVE_LUA
	str_map_free (&g_ctx.coders);
#endif // HAVE_LUA

	return 0;
}