all messages for Emacs-related lists mirrored at yhetil.org
 help / color / mirror / code / Atom feed
blob 7f7d7359ffc21e36307b16cac31ea84cd4557971 72330 bytes (raw)
name: src/textprop.c 	 # note: path name is non-authoritative(*)

   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
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
 
/* Interface code for dealing with text properties.
   Copyright (C) 1993-1995, 1997, 1999-2018 Free Software Foundation,
   Inc.

This file is part of GNU Emacs.

GNU Emacs is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at
your option) any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include "lisp.h"
#include "intervals.h"
#include "buffer.h"
#include "window.h"

/* Test for membership, allowing for t (actually any non-cons) to mean the
   universal set.  */

#define TMEM(sym, set) (CONSP (set) ? ! NILP (Fmemq (sym, set)) : ! NILP (set))
\f

/* NOTES:  previous- and next- property change will have to skip
  zero-length intervals if they are implemented.  This could be done
  inside next_interval and previous_interval.

  set_properties needs to deal with the interval property cache.

  It is assumed that for any interval plist, a property appears
  only once on the list.  Although some code i.e., remove_properties,
  handles the more general case, the uniqueness of properties is
  necessary for the system to remain consistent.  This requirement
  is enforced by the subrs installing properties onto the intervals.  */

\f

enum property_set_type
{
  TEXT_PROPERTY_REPLACE,
  TEXT_PROPERTY_PREPEND,
  TEXT_PROPERTY_APPEND
};

/* If o1 is a cons whose cdr is a cons, return true and set o2 to
   the o1's cdr.  Otherwise, return false.  This is handy for
   traversing plists.  */
#define PLIST_ELT_P(o1, o2) (CONSP (o1) && ((o2)=XCDR (o1), CONSP (o2)))

/* verify_interval_modification saves insertion hooks here
   to be run later by report_interval_modification.  */
static Lisp_Object interval_insert_behind_hooks;
static Lisp_Object interval_insert_in_front_hooks;


/* Signal a `text-read-only' error.  This function makes it easier
   to capture that error in GDB by putting a breakpoint on it.  */

static _Noreturn void
text_read_only (Lisp_Object propval)
{
  if (STRINGP (propval))
    xsignal1 (Qtext_read_only, propval);

  xsignal0 (Qtext_read_only);
}

/* Prepare to modify the text properties of BUFFER from START to END.  */

static void
modify_text_properties (Lisp_Object buffer, Lisp_Object start, Lisp_Object end)
{
  ptrdiff_t b = XINT (start), e = XINT (end);
  struct buffer *buf = XBUFFER (buffer), *old = current_buffer;

  set_buffer_internal (buf);

  prepare_to_modify_buffer_1 (b, e, NULL);

  BUF_COMPUTE_UNCHANGED (buf, b - 1, e);
  if (MODIFF <= SAVE_MODIFF)
    record_first_change ();
  MODIFF++;

  bset_point_before_scroll (current_buffer, Qnil);

  set_buffer_internal (old);
}

/* Complain if object is not string or buffer type.  */

static void
CHECK_STRING_OR_BUFFER (Lisp_Object x)
{
  CHECK_TYPE (STRINGP (x) || BUFFERP (x), Qbuffer_or_string_p, x);
}

/* Extract the interval at the position pointed to by BEGIN from
   OBJECT, a string or buffer.  Additionally, check that the positions
   pointed to by BEGIN and END are within the bounds of OBJECT, and
   reverse them if *BEGIN is greater than *END.  The objects pointed
   to by BEGIN and END may be integers or markers; if the latter, they
   are coerced to integers.

   When OBJECT is a string, we increment *BEGIN and *END
   to make them origin-one.

   Note that buffer points don't correspond to interval indices.
   For example, point-max is 1 greater than the index of the last
   character.  This difference is handled in the caller, which uses
   the validated points to determine a length, and operates on that.
   Exceptions are Ftext_properties_at, Fnext_property_change, and
   Fprevious_property_change which call this function with BEGIN == END.
   Handle this case specially.

   If FORCE is soft (false), it's OK to return NULL.  Otherwise,
   create an interval tree for OBJECT if one doesn't exist, provided
   the object actually contains text.  In the current design, if there
   is no text, there can be no text properties.  */

enum { soft = false, hard = true };

INTERVAL
validate_interval_range (Lisp_Object object, Lisp_Object *begin,
			 Lisp_Object *end, bool force)
{
  INTERVAL i;
  ptrdiff_t searchpos;

  CHECK_STRING_OR_BUFFER (object);
  CHECK_NUMBER_COERCE_MARKER (*begin);
  CHECK_NUMBER_COERCE_MARKER (*end);

  /* If we are asked for a point, but from a subr which operates
     on a range, then return nothing.  */
  if (EQ (*begin, *end) && begin != end)
    return NULL;

  if (XINT (*begin) > XINT (*end))
    {
      Lisp_Object n;
      n = *begin;
      *begin = *end;
      *end = n;
    }

  if (BUFFERP (object))
    {
      register struct buffer *b = XBUFFER (object);

      if (!(BUF_BEGV (b) <= XINT (*begin) && XINT (*begin) <= XINT (*end)
	    && XINT (*end) <= BUF_ZV (b)))
	args_out_of_range (*begin, *end);
      i = buffer_intervals (b);

      /* If there's no text, there are no properties.  */
      if (BUF_BEGV (b) == BUF_ZV (b))
	return NULL;

      searchpos = XINT (*begin);
    }
  else
    {
      ptrdiff_t len = SCHARS (object);

      if (! (0 <= XINT (*begin) && XINT (*begin) <= XINT (*end)
	     && XINT (*end) <= len))
	args_out_of_range (*begin, *end);
      XSETFASTINT (*begin, XFASTINT (*begin));
      if (begin != end)
	XSETFASTINT (*end, XFASTINT (*end));
      i = string_intervals (object);

      if (len == 0)
	return NULL;

      searchpos = XINT (*begin);
    }

  if (!i)
    return (force ? create_root_interval (object) : i);

  return find_interval (i, searchpos);
}

/* Validate LIST as a property list.  If LIST is not a list, then
   make one consisting of (LIST nil).  Otherwise, verify that LIST
   is even numbered and thus suitable as a plist.  */

static Lisp_Object
validate_plist (Lisp_Object list)
{
  if (NILP (list))
    return Qnil;

  if (CONSP (list))
    {
      Lisp_Object tail = list;
      do
	{
	  tail = XCDR (tail);
	  if (! CONSP (tail))
	    error ("Odd length text property list");
	  tail = XCDR (tail);
	  maybe_quit ();
	}
      while (CONSP (tail));

      return list;
    }

  return list2 (list, Qnil);
}

/* Return true if interval I has all the properties,
   with the same values, of list PLIST.  */

static bool
interval_has_all_properties (Lisp_Object plist, INTERVAL i)
{
  Lisp_Object tail1, tail2;

  /* Go through each element of PLIST.  */
  for (tail1 = plist; CONSP (tail1); tail1 = Fcdr (XCDR (tail1)))
    {
      Lisp_Object sym1 = XCAR (tail1);
      bool found = false;

      /* Go through I's plist, looking for sym1 */
      for (tail2 = i->plist; CONSP (tail2); tail2 = Fcdr (XCDR (tail2)))
	if (EQ (sym1, XCAR (tail2)))
	  {
	    /* Found the same property on both lists.  If the
	       values are unequal, return false.  */
	    if (! EQ (Fcar (XCDR (tail1)), Fcar (XCDR (tail2))))
	      return false;

	    /* Property has same value on both lists; go to next one.  */
	    found = true;
	    break;
	  }

      if (! found)
	return false;
    }

  return true;
}

/* Return true if the plist of interval I has any of the
   properties of PLIST, regardless of their values.  */

static bool
interval_has_some_properties (Lisp_Object plist, INTERVAL i)
{
  Lisp_Object tail1, tail2, sym;

  /* Go through each element of PLIST.  */
  for (tail1 = plist; CONSP (tail1); tail1 = Fcdr (XCDR (tail1)))
    {
      sym = XCAR (tail1);

      /* Go through i's plist, looking for tail1 */
      for (tail2 = i->plist; CONSP (tail2); tail2 = Fcdr (XCDR (tail2)))
	if (EQ (sym, XCAR (tail2)))
	  return true;
    }

  return false;
}

/* Return true if the plist of interval I has any of the
   property names in LIST, regardless of their values.  */

static bool
interval_has_some_properties_list (Lisp_Object list, INTERVAL i)
{
  Lisp_Object tail1, tail2, sym;

  /* Go through each element of LIST.  */
  for (tail1 = list; CONSP (tail1); tail1 = XCDR (tail1))
    {
      sym = XCAR (tail1);

      /* Go through i's plist, looking for tail1 */
      for (tail2 = i->plist; CONSP (tail2); tail2 = XCDR (XCDR (tail2)))
	if (EQ (sym, XCAR (tail2)))
	  return true;
    }

  return false;
}
\f
/* Changing the plists of individual intervals.  */

/* Return the value of PROP in property-list PLIST, or Qunbound if it
   has none.  */
static Lisp_Object
property_value (Lisp_Object plist, Lisp_Object prop)
{
  Lisp_Object value;

  while (PLIST_ELT_P (plist, value))
    if (EQ (XCAR (plist), prop))
      return XCAR (value);
    else
      plist = XCDR (value);

  return Qunbound;
}

/* Set the properties of INTERVAL to PROPERTIES,
   and record undo info for the previous values.
   OBJECT is the string or buffer that INTERVAL belongs to.  */

static void
set_properties (Lisp_Object properties, INTERVAL interval, Lisp_Object object)
{
  Lisp_Object sym, value;

  if (BUFFERP (object))
    {
      /* For each property in the old plist which is missing from PROPERTIES,
	 or has a different value in PROPERTIES, make an undo record.  */
      for (sym = interval->plist;
	   PLIST_ELT_P (sym, value);
	   sym = XCDR (value))
	if (! EQ (property_value (properties, XCAR (sym)),
		  XCAR (value)))
	  {
	    record_property_change (interval->position, LENGTH (interval),
				    XCAR (sym), XCAR (value),
				    object);
	  }

      /* For each new property that has no value at all in the old plist,
	 make an undo record binding it to nil, so it will be removed.  */
      for (sym = properties;
	   PLIST_ELT_P (sym, value);
	   sym = XCDR (value))
	if (EQ (property_value (interval->plist, XCAR (sym)), Qunbound))
	  {
	    record_property_change (interval->position, LENGTH (interval),
				    XCAR (sym), Qnil,
				    object);
	  }
    }

  /* Store new properties.  */
  set_interval_plist (interval, Fcopy_sequence (properties));
}

/* Add the properties of PLIST to the interval I, or set
   the value of I's property to the value of the property on PLIST
   if they are different.

   OBJECT should be the string or buffer the interval is in.

   Return true if this changes I (i.e., if any members of PLIST
   are actually added to I's plist) */

static bool
add_properties (Lisp_Object plist, INTERVAL i, Lisp_Object object,
		enum property_set_type set_type)
{
  Lisp_Object tail1, tail2, sym1, val1;
  bool changed = false;

  tail1 = plist;
  sym1 = Qnil;
  val1 = Qnil;

  /* Go through each element of PLIST.  */
  for (tail1 = plist; CONSP (tail1); tail1 = Fcdr (XCDR (tail1)))
    {
      bool found = false;
      sym1 = XCAR (tail1);
      val1 = Fcar (XCDR (tail1));

      /* Go through I's plist, looking for sym1 */
      for (tail2 = i->plist; CONSP (tail2); tail2 = Fcdr (XCDR (tail2)))
	if (EQ (sym1, XCAR (tail2)))
	  {
	    Lisp_Object this_cdr;

	    this_cdr = XCDR (tail2);
	    /* Found the property.  Now check its value.  */
	    found = true;

	    /* The properties have the same value on both lists.
	       Continue to the next property.  */
	    if (EQ (val1, Fcar (this_cdr)))
	      break;

	    /* Record this change in the buffer, for undo purposes.  */
	    if (BUFFERP (object))
	      {
		record_property_change (i->position, LENGTH (i),
					sym1, Fcar (this_cdr), object);
	      }

	    /* I's property has a different value -- change it */
	    if (set_type == TEXT_PROPERTY_REPLACE)
	      Fsetcar (this_cdr, val1);
	    else {
	      if (CONSP (Fcar (this_cdr)) &&
		  /* Special-case anonymous face properties. */
		  (! EQ (sym1, Qface) ||
		   NILP (Fkeywordp (Fcar (Fcar (this_cdr))))))
		/* The previous value is a list, so prepend (or
		   append) the new value to this list. */
		if (set_type == TEXT_PROPERTY_PREPEND)
		  Fsetcar (this_cdr, Fcons (val1, Fcar (this_cdr)));
		else
		  nconc2 (Fcar (this_cdr), list1 (val1));
	      else {
		/* The previous value is a single value, so make it
		   into a list. */
		if (set_type == TEXT_PROPERTY_PREPEND)
		  Fsetcar (this_cdr, list2 (val1, Fcar (this_cdr)));
		else
		  Fsetcar (this_cdr, list2 (Fcar (this_cdr), val1));
	      }
	    }
	    changed = true;
	    break;
	  }

      if (! found)
	{
	  /* Record this change in the buffer, for undo purposes.  */
	  if (BUFFERP (object))
	    {
	      record_property_change (i->position, LENGTH (i),
				      sym1, Qnil, object);
	    }
	  set_interval_plist (i, Fcons (sym1, Fcons (val1, i->plist)));
	  changed = true;
	}
    }

  return changed;
}

/* For any members of PLIST, or LIST,
   which are properties of I, remove them from I's plist.
   (If PLIST is non-nil, use that, otherwise use LIST.)
   OBJECT is the string or buffer containing I.  */

static bool
remove_properties (Lisp_Object plist, Lisp_Object list, INTERVAL i, Lisp_Object object)
{
  bool changed = false;

  /* True means tail1 is a plist, otherwise it is a list.  */
  bool use_plist = ! NILP (plist);
  Lisp_Object tail1 = use_plist ? plist : list;

  Lisp_Object current_plist = i->plist;

  /* Go through each element of LIST or PLIST.  */
  while (CONSP (tail1))
    {
      Lisp_Object sym = XCAR (tail1);

      /* First, remove the symbol if it's at the head of the list */
      while (CONSP (current_plist) && EQ (sym, XCAR (current_plist)))
	{
	  if (BUFFERP (object))
	    record_property_change (i->position, LENGTH (i),
				    sym, XCAR (XCDR (current_plist)),
				    object);

	  current_plist = XCDR (XCDR (current_plist));
	  changed = true;
	}

      /* Go through I's plist, looking for SYM.  */
      Lisp_Object tail2 = current_plist;
      while (! NILP (tail2))
	{
	  Lisp_Object this = XCDR (XCDR (tail2));
	  if (CONSP (this) && EQ (sym, XCAR (this)))
	    {
	      if (BUFFERP (object))
		record_property_change (i->position, LENGTH (i),
					sym, XCAR (XCDR (this)), object);

	      Fsetcdr (XCDR (tail2), XCDR (XCDR (this)));
	      changed = true;
	    }
	  tail2 = this;
	}

      /* Advance thru TAIL1 one way or the other.  */
      tail1 = XCDR (tail1);
      if (use_plist && CONSP (tail1))
	tail1 = XCDR (tail1);
    }

  if (changed)
    set_interval_plist (i, current_plist);
  return changed;
}
\f
/* Returns the interval of POSITION in OBJECT.
   POSITION is BEG-based.  */

INTERVAL
interval_of (ptrdiff_t position, Lisp_Object object)
{
  register INTERVAL i;
  ptrdiff_t beg, end;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);
  else if (EQ (object, Qt))
    return NULL;

  CHECK_STRING_OR_BUFFER (object);

  if (BUFFERP (object))
    {
      register struct buffer *b = XBUFFER (object);

      beg = BUF_BEGV (b);
      end = BUF_ZV (b);
      i = buffer_intervals (b);
    }
  else
    {
      beg = 0;
      end = SCHARS (object);
      i = string_intervals (object);
    }

  if (!(beg <= position && position <= end))
    args_out_of_range (make_number (position), make_number (position));
  if (beg == end || !i)
    return NULL;

  return find_interval (i, position);
}
\f
DEFUN ("text-properties-at", Ftext_properties_at,
       Stext_properties_at, 1, 2, 0,
       doc: /* Return the list of properties of the character at POSITION in OBJECT.
If the optional second argument OBJECT is a buffer (or nil, which means
the current buffer), POSITION is a buffer position (integer or marker).
If OBJECT is a string, POSITION is a 0-based index into it.
If POSITION is at the end of OBJECT, the value is nil.  */)
  (Lisp_Object position, Lisp_Object object)
{
  register INTERVAL i;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  i = validate_interval_range (object, &position, &position, soft);
  if (!i)
    return Qnil;
  /* If POSITION is at the end of the interval,
     it means it's the end of OBJECT.
     There are no properties at the very end,
     since no character follows.  */
  if (XINT (position) == LENGTH (i) + i->position)
    return Qnil;

  return i->plist;
}

DEFUN ("get-text-property", Fget_text_property, Sget_text_property, 2, 3, 0,
       doc: /* Return the value of POSITION's property PROP, in OBJECT.
OBJECT should be a buffer or a string; if omitted or nil, it defaults
to the current buffer.
If POSITION is at the end of OBJECT, the value is nil.  */)
  (Lisp_Object position, Lisp_Object prop, Lisp_Object object)
{
  return textget (Ftext_properties_at (position, object), prop);
}

/* Return the value of char's property PROP, in OBJECT at POSITION.
   OBJECT is optional and defaults to the current buffer.
   If OVERLAY is non-0, then in the case that the returned property is from
   an overlay, the overlay found is returned in *OVERLAY, otherwise nil is
   returned in *OVERLAY.
   If POSITION is at the end of OBJECT, the value is nil.
   If OBJECT is a buffer, then overlay properties are considered as well as
   text properties.
   If OBJECT is a window, then that window's buffer is used, but
   window-specific overlays are considered only if they are associated
   with OBJECT. */
Lisp_Object
get_char_property_and_overlay (Lisp_Object position, register Lisp_Object prop, Lisp_Object object, Lisp_Object *overlay)
{
  struct window *w = 0;

  CHECK_NUMBER_COERCE_MARKER (position);

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  if (WINDOWP (object))
    {
      CHECK_LIVE_WINDOW (object);
      w = XWINDOW (object);
      object = w->contents;
    }
  if (BUFFERP (object))
    {
      ptrdiff_t noverlays;
      Lisp_Object *overlay_vec;
      struct buffer *obuf = current_buffer;

      if (XINT (position) < BUF_BEGV (XBUFFER (object))
	  || XINT (position) > BUF_ZV (XBUFFER (object)))
	xsignal1 (Qargs_out_of_range, position);

      set_buffer_temp (XBUFFER (object));

      USE_SAFE_ALLOCA;
      GET_OVERLAYS_AT (XINT (position), overlay_vec, noverlays, NULL, false);
      noverlays = sort_overlays (overlay_vec, noverlays, w);

      set_buffer_temp (obuf);

      /* Now check the overlays in order of decreasing priority.  */
      while (--noverlays >= 0)
	{
	  Lisp_Object tem = Foverlay_get (overlay_vec[noverlays], prop);
	  if (!NILP (tem))
	    {
	      if (overlay)
		/* Return the overlay we got the property from.  */
		*overlay = overlay_vec[noverlays];
	      SAFE_FREE ();
	      return tem;
	    }
	}
      SAFE_FREE ();
    }

  if (overlay)
    /* Indicate that the return value is not from an overlay.  */
    *overlay = Qnil;

  /* Not a buffer, or no appropriate overlay, so fall through to the
     simpler case.  */
  return Fget_text_property (position, prop, object);
}

DEFUN ("get-char-property", Fget_char_property, Sget_char_property, 2, 3, 0,
       doc: /* Return the value of POSITION's property PROP, in OBJECT.
Both overlay properties and text properties are checked.
OBJECT is optional and defaults to the current buffer.
If POSITION is at the end of OBJECT, the value is nil.
If OBJECT is a buffer, then overlay properties are considered as well as
text properties.
If OBJECT is a window, then that window's buffer is used, but window-specific
overlays are considered only if they are associated with OBJECT.  */)
  (Lisp_Object position, Lisp_Object prop, Lisp_Object object)
{
  return get_char_property_and_overlay (position, prop, object, 0);
}

DEFUN ("get-char-property-and-overlay", Fget_char_property_and_overlay,
       Sget_char_property_and_overlay, 2, 3, 0,
       doc: /* Like `get-char-property', but with extra overlay information.
The value is a cons cell.  Its car is the return value of `get-char-property'
with the same arguments--that is, the value of POSITION's property
PROP in OBJECT.  Its cdr is the overlay in which the property was
found, or nil, if it was found as a text property or not found at all.

OBJECT is optional and defaults to the current buffer.  OBJECT may be
a string, a buffer or a window.  For strings, the cdr of the return
value is always nil, since strings do not have overlays.  If OBJECT is
a window, then that window's buffer is used, but window-specific
overlays are considered only if they are associated with OBJECT.  If
POSITION is at the end of OBJECT, both car and cdr are nil.  */)
  (Lisp_Object position, Lisp_Object prop, Lisp_Object object)
{
  Lisp_Object overlay;
  Lisp_Object val
    = get_char_property_and_overlay (position, prop, object, &overlay);
  return Fcons (val, overlay);
}

\f
DEFUN ("next-char-property-change", Fnext_char_property_change,
       Snext_char_property_change, 1, 2, 0,
       doc: /* Return the position of next text property or overlay change.
This scans characters forward in the current buffer from POSITION till
it finds a change in some text property, or the beginning or end of an
overlay, and returns the position of that.
If none is found, and LIMIT is nil or omitted, the function
returns (point-max).

If the optional second argument LIMIT is non-nil, the function doesn't
search past position LIMIT, and returns LIMIT if nothing is found
before LIMIT.  LIMIT is a no-op if it is greater than (point-max).  */)
  (Lisp_Object position, Lisp_Object limit)
{
  Lisp_Object temp;

  temp = Fnext_overlay_change (position);
  if (! NILP (limit))
    {
      CHECK_NUMBER_COERCE_MARKER (limit);
      if (XINT (limit) < XINT (temp))
	temp = limit;
    }
  return Fnext_property_change (position, Qnil, temp);
}

DEFUN ("previous-char-property-change", Fprevious_char_property_change,
       Sprevious_char_property_change, 1, 2, 0,
       doc: /* Return the position of previous text property or overlay change.
Scans characters backward in the current buffer from POSITION till it
finds a change in some text property, or the beginning or end of an
overlay, and returns the position of that.
If none is found, and LIMIT is nil or omitted, the function
returns (point-min).

If the optional second argument LIMIT is non-nil, the function doesn't
search before position LIMIT, and returns LIMIT if nothing is found
before LIMIT.  LIMIT is a no-op if it is less than (point-min).  */)
  (Lisp_Object position, Lisp_Object limit)
{
  Lisp_Object temp;

  temp = Fprevious_overlay_change (position);
  if (! NILP (limit))
    {
      CHECK_NUMBER_COERCE_MARKER (limit);
      if (XINT (limit) > XINT (temp))
	temp = limit;
    }
  return Fprevious_property_change (position, Qnil, temp);
}


DEFUN ("next-single-char-property-change", Fnext_single_char_property_change,
       Snext_single_char_property_change, 2, 4, 0,
       doc: /* Return the position of next text property or overlay change for a specific property.
Scans characters forward from POSITION till it finds
a change in the PROP property, then returns the position of the change.
If the optional third argument OBJECT is a buffer (or nil, which means
the current buffer), POSITION is a buffer position (integer or marker).
If OBJECT is a string, POSITION is a 0-based index into it.

In a string, scan runs to the end of the string, unless LIMIT is non-nil.
In a buffer, if LIMIT is nil or omitted, it runs to (point-max), and the
value cannot exceed that.
If the optional fourth argument LIMIT is non-nil, don't search
past position LIMIT; return LIMIT if nothing is found before LIMIT.

The property values are compared with `eq'.
If the property is constant all the way to the end of OBJECT, return the
last valid position in OBJECT.  */)
  (Lisp_Object position, Lisp_Object prop, Lisp_Object object, Lisp_Object limit)
{
  if (STRINGP (object))
    {
      position = Fnext_single_property_change (position, prop, object, limit);
      if (NILP (position))
	{
	  if (NILP (limit))
	    position = make_number (SCHARS (object));
	  else
	    {
	      CHECK_NUMBER (limit);
	      position = limit;
	    }
	}
    }
  else
    {
      Lisp_Object initial_value, value;
      ptrdiff_t count = SPECPDL_INDEX ();

      if (! NILP (object))
	CHECK_BUFFER (object);

      if (BUFFERP (object) && current_buffer != XBUFFER (object))
	{
	  record_unwind_current_buffer ();
	  Fset_buffer (object);
	}

      CHECK_NUMBER_COERCE_MARKER (position);

      initial_value = Fget_char_property (position, prop, object);

      if (NILP (limit))
	XSETFASTINT (limit, ZV);
      else
	CHECK_NUMBER_COERCE_MARKER (limit);

      if (XFASTINT (position) >= XFASTINT (limit))
	{
	  position = limit;
	  if (XFASTINT (position) > ZV)
	    XSETFASTINT (position, ZV);
	}
      else
	while (true)
	  {
	    position = Fnext_char_property_change (position, limit);
	    if (XFASTINT (position) >= XFASTINT (limit))
	      {
		position = limit;
		break;
	      }

	    value = Fget_char_property (position, prop, object);
	    if (!EQ (value, initial_value))
	      break;
	  }

      unbind_to (count, Qnil);
    }

  return position;
}

DEFUN ("previous-single-char-property-change",
       Fprevious_single_char_property_change,
       Sprevious_single_char_property_change, 2, 4, 0,
       doc: /* Return the position of previous text property or overlay change for a specific property.
Scans characters backward from POSITION till it finds
a change in the PROP property, then returns the position of the change.
If the optional third argument OBJECT is a buffer (or nil, which means
the current buffer), POSITION is a buffer position (integer or marker).
If OBJECT is a string, POSITION is a 0-based index into it.

In a string, scan runs to the start of the string, unless LIMIT is non-nil.
In a buffer, if LIMIT is nil or omitted, it runs to (point-min), and the
value cannot be less than that.
If the optional fourth argument LIMIT is non-nil, don't search back past
position LIMIT; return LIMIT if nothing is found before reaching LIMIT.

The property values are compared with `eq'.
If the property is constant all the way to the start of OBJECT, return the
first valid position in OBJECT.  */)
  (Lisp_Object position, Lisp_Object prop, Lisp_Object object, Lisp_Object limit)
{
  if (STRINGP (object))
    {
      position = Fprevious_single_property_change (position, prop, object, limit);
      if (NILP (position))
	{
	  if (NILP (limit))
	    position = make_number (0);
	  else
	    {
	      CHECK_NUMBER (limit);
	      position = limit;
	    }
	}
    }
  else
    {
      ptrdiff_t count = SPECPDL_INDEX ();

      if (! NILP (object))
	CHECK_BUFFER (object);

      if (BUFFERP (object) && current_buffer != XBUFFER (object))
	{
	  record_unwind_current_buffer ();
	  Fset_buffer (object);
	}

      CHECK_NUMBER_COERCE_MARKER (position);

      if (NILP (limit))
	XSETFASTINT (limit, BEGV);
      else
	CHECK_NUMBER_COERCE_MARKER (limit);

      if (XFASTINT (position) <= XFASTINT (limit))
	{
	  position = limit;
	  if (XFASTINT (position) < BEGV)
	    XSETFASTINT (position, BEGV);
	}
      else
	{
	  Lisp_Object initial_value
	    = Fget_char_property (make_number (XFASTINT (position) - 1),
				  prop, object);

	  while (true)
	    {
	      position = Fprevious_char_property_change (position, limit);

	      if (XFASTINT (position) <= XFASTINT (limit))
		{
		  position = limit;
		  break;
		}
	      else
		{
		  Lisp_Object value
		    = Fget_char_property (make_number (XFASTINT (position) - 1),
					  prop, object);

		  if (!EQ (value, initial_value))
		    break;
		}
	    }
	}

      unbind_to (count, Qnil);
    }

  return position;
}
\f
DEFUN ("next-property-change", Fnext_property_change,
       Snext_property_change, 1, 3, 0,
       doc: /* Return the position of next property change.
Scans characters forward from POSITION in OBJECT till it finds
a change in some text property, then returns the position of the change.
If the optional second argument OBJECT is a buffer (or nil, which means
the current buffer), POSITION is a buffer position (integer or marker).
If OBJECT is a string, POSITION is a 0-based index into it.
Return nil if LIMIT is nil or omitted, and the property is constant all
the way to the end of OBJECT; if the value is non-nil, it is a position
greater than POSITION, never equal.

If the optional third argument LIMIT is non-nil, don't search
past position LIMIT; return LIMIT if nothing is found before LIMIT.  */)
  (Lisp_Object position, Lisp_Object object, Lisp_Object limit)
{
  register INTERVAL i, next;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  if (!NILP (limit) && !EQ (limit, Qt))
    CHECK_NUMBER_COERCE_MARKER (limit);

  i = validate_interval_range (object, &position, &position, soft);

  /* If LIMIT is t, return start of next interval--don't
     bother checking further intervals.  */
  if (EQ (limit, Qt))
    {
      if (!i)
	next = i;
      else
	next = next_interval (i);

      if (!next)
	XSETFASTINT (position, (STRINGP (object)
				? SCHARS (object)
				: BUF_ZV (XBUFFER (object))));
      else
	XSETFASTINT (position, next->position);
      return position;
    }

  if (!i)
    return limit;

  next = next_interval (i);

  while (next && intervals_equal (i, next)
	 && (NILP (limit) || next->position < XFASTINT (limit)))
    next = next_interval (next);

  if (!next
      || (next->position
	  >= (INTEGERP (limit)
	      ? XFASTINT (limit)
	      : (STRINGP (object)
		 ? SCHARS (object)
		 : BUF_ZV (XBUFFER (object))))))
    return limit;
  else
    return make_number (next->position);
}

DEFUN ("next-single-property-change", Fnext_single_property_change,
       Snext_single_property_change, 2, 4, 0,
       doc: /* Return the position of next property change for a specific property.
Scans characters forward from POSITION till it finds
a change in the PROP property, then returns the position of the change.
If the optional third argument OBJECT is a buffer (or nil, which means
the current buffer), POSITION is a buffer position (integer or marker).
If OBJECT is a string, POSITION is a 0-based index into it.
The property values are compared with `eq'.
Return nil if LIMIT is nil or omitted, and the property is constant all
the way to the end of OBJECT; if the value is non-nil, it is a position
greater than POSITION, never equal.

If the optional fourth argument LIMIT is non-nil, don't search
past position LIMIT; return LIMIT if nothing is found before LIMIT.  */)
  (Lisp_Object position, Lisp_Object prop, Lisp_Object object, Lisp_Object limit)
{
  register INTERVAL i, next;
  register Lisp_Object here_val;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  if (!NILP (limit))
    CHECK_NUMBER_COERCE_MARKER (limit);

  i = validate_interval_range (object, &position, &position, soft);
  if (!i)
    return limit;

  here_val = textget (i->plist, prop);
  next = next_interval (i);
  while (next
	 && EQ (here_val, textget (next->plist, prop))
	 && (NILP (limit) || next->position < XFASTINT (limit)))
    next = next_interval (next);

  if (!next
      || (next->position
	  >= (INTEGERP (limit)
	      ? XFASTINT (limit)
	      : (STRINGP (object)
		 ? SCHARS (object)
		 : BUF_ZV (XBUFFER (object))))))
    return limit;
  else
    return make_number (next->position);
}

DEFUN ("previous-property-change", Fprevious_property_change,
       Sprevious_property_change, 1, 3, 0,
       doc: /* Return the position of previous property change.
Scans characters backwards from POSITION in OBJECT till it finds
a change in some text property, then returns the position of the change.
If the optional second argument OBJECT is a buffer (or nil, which means
the current buffer), POSITION is a buffer position (integer or marker).
If OBJECT is a string, POSITION is a 0-based index into it.
Return nil if LIMIT is nil or omitted, and the property is constant all
the way to the start of OBJECT; if the value is non-nil, it is a position
less than POSITION, never equal.

If the optional third argument LIMIT is non-nil, don't search
back past position LIMIT; return LIMIT if nothing is found until LIMIT.  */)
  (Lisp_Object position, Lisp_Object object, Lisp_Object limit)
{
  register INTERVAL i, previous;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  if (!NILP (limit))
    CHECK_NUMBER_COERCE_MARKER (limit);

  i = validate_interval_range (object, &position, &position, soft);
  if (!i)
    return limit;

  /* Start with the interval containing the char before point.  */
  if (i->position == XFASTINT (position))
    i = previous_interval (i);

  previous = previous_interval (i);
  while (previous && intervals_equal (previous, i)
	 && (NILP (limit)
	     || (previous->position + LENGTH (previous) > XFASTINT (limit))))
    previous = previous_interval (previous);

  if (!previous
      || (previous->position + LENGTH (previous)
	  <= (INTEGERP (limit)
	      ? XFASTINT (limit)
	      : (STRINGP (object) ? 0 : BUF_BEGV (XBUFFER (object))))))
    return limit;
  else
    return make_number (previous->position + LENGTH (previous));
}

DEFUN ("previous-single-property-change", Fprevious_single_property_change,
       Sprevious_single_property_change, 2, 4, 0,
       doc: /* Return the position of previous property change for a specific property.
Scans characters backward from POSITION till it finds
a change in the PROP property, then returns the position of the change.
If the optional third argument OBJECT is a buffer (or nil, which means
the current buffer), POSITION is a buffer position (integer or marker).
If OBJECT is a string, POSITION is a 0-based index into it.
The property values are compared with `eq'.
Return nil if LIMIT is nil or omitted, and the property is constant all
the way to the start of OBJECT; if the value is non-nil, it is a position
less than POSITION, never equal.

If the optional fourth argument LIMIT is non-nil, don't search
back past position LIMIT; return LIMIT if nothing is found until LIMIT.  */)
  (Lisp_Object position, Lisp_Object prop, Lisp_Object object, Lisp_Object limit)
{
  register INTERVAL i, previous;
  register Lisp_Object here_val;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  if (!NILP (limit))
    CHECK_NUMBER_COERCE_MARKER (limit);

  i = validate_interval_range (object, &position, &position, soft);

  /* Start with the interval containing the char before point.  */
  if (i && i->position == XFASTINT (position))
    i = previous_interval (i);

  if (!i)
    return limit;

  here_val = textget (i->plist, prop);
  previous = previous_interval (i);
  while (previous
	 && EQ (here_val, textget (previous->plist, prop))
	 && (NILP (limit)
	     || (previous->position + LENGTH (previous) > XFASTINT (limit))))
    previous = previous_interval (previous);

  if (!previous
      || (previous->position + LENGTH (previous)
	  <= (INTEGERP (limit)
	      ? XFASTINT (limit)
	      : (STRINGP (object) ? 0 : BUF_BEGV (XBUFFER (object))))))
    return limit;
  else
    return make_number (previous->position + LENGTH (previous));
}
\f
/* Used by add-text-properties and add-face-text-property. */

static Lisp_Object
add_text_properties_1 (Lisp_Object start, Lisp_Object end,
		       Lisp_Object properties, Lisp_Object object,
		       enum property_set_type set_type) {
  INTERVAL i, unchanged;
  ptrdiff_t s, len;
  bool modified = false;
  bool first_time = true;

  properties = validate_plist (properties);
  if (NILP (properties))
    return Qnil;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

 retry:
  i = validate_interval_range (object, &start, &end, hard);
  if (!i)
    return Qnil;

  s = XINT (start);
  len = XINT (end) - s;

  /* If this interval already has the properties, we can skip it.  */
  if (interval_has_all_properties (properties, i))
    {
      ptrdiff_t got = LENGTH (i) - (s - i->position);

      do
	{
	  if (got >= len)
	    return Qnil;
	  len -= got;
	  i = next_interval (i);
	  got = LENGTH (i);
	}
      while (interval_has_all_properties (properties, i));
    }
  else if (i->position != s)
    {
      /* If we're not starting on an interval boundary, we have to
	 split this interval.  */
      unchanged = i;
      i = split_interval_right (unchanged, s - unchanged->position);
      copy_properties (unchanged, i);
    }

  if (BUFFERP (object) && first_time)
    {
      ptrdiff_t prev_total_length = TOTAL_LENGTH (i);
      ptrdiff_t prev_pos = i->position;

      modify_text_properties (object, start, end);
      /* If someone called us recursively as a side effect of
	 modify_text_properties, and changed the intervals behind our back
	 (could happen if lock_file, called by prepare_to_modify_buffer,
	 triggers redisplay, and that calls add-text-properties again
	 in the same buffer), we cannot continue with I, because its
	 data changed.  So we restart the interval analysis anew.  */
      if (TOTAL_LENGTH (i) != prev_total_length
	  || i->position != prev_pos)
	{
	  first_time = false;
	  goto retry;
	}
    }

  /* We are at the beginning of interval I, with LEN chars to scan.  */
  for (;;)
    {
      eassert (i != 0);

      if (LENGTH (i) >= len)
	{
	  if (interval_has_all_properties (properties, i))
	    {
	      if (BUFFERP (object))
		signal_after_change (XINT (start), XINT (end) - XINT (start),
				     XINT (end) - XINT (start));

	      eassert (modified);
	      return Qt;
	    }

	  if (LENGTH (i) == len)
	    {
	      add_properties (properties, i, object, set_type);
	      if (BUFFERP (object))
		signal_after_change (XINT (start), XINT (end) - XINT (start),
				     XINT (end) - XINT (start));
	      return Qt;
	    }

	  /* i doesn't have the properties, and goes past the change limit */
	  unchanged = i;
	  i = split_interval_left (unchanged, len);
	  copy_properties (unchanged, i);
	  add_properties (properties, i, object, set_type);
	  if (BUFFERP (object))
	    signal_after_change (XINT (start), XINT (end) - XINT (start),
				 XINT (end) - XINT (start));
	  return Qt;
	}

      len -= LENGTH (i);
      modified |= add_properties (properties, i, object, set_type);
      i = next_interval (i);
    }
}

/* Callers note, this can GC when OBJECT is a buffer (or nil).  */

DEFUN ("add-text-properties", Fadd_text_properties,
       Sadd_text_properties, 3, 4, 0,
       doc: /* Add properties to the text from START to END.
The third argument PROPERTIES is a property list
specifying the property values to add.  If the optional fourth argument
OBJECT is a buffer (or nil, which means the current buffer),
START and END are buffer positions (integers or markers).
If OBJECT is a string, START and END are 0-based indices into it.
Return t if any property value actually changed, nil otherwise.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object properties,
   Lisp_Object object)
{
  return add_text_properties_1 (start, end, properties, object,
				TEXT_PROPERTY_REPLACE);
}

/* Callers note, this can GC when OBJECT is a buffer (or nil).  */

DEFUN ("put-text-property", Fput_text_property,
       Sput_text_property, 4, 5, 0,
       doc: /* Set one property of the text from START to END.
The third and fourth arguments PROPERTY and VALUE
specify the property to add.
If the optional fifth argument OBJECT is a buffer (or nil, which means
the current buffer), START and END are buffer positions (integers or
markers).  If OBJECT is a string, START and END are 0-based indices into it.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object property,
   Lisp_Object value, Lisp_Object object)
{
  AUTO_LIST2 (properties, property, value);
  Fadd_text_properties (start, end, properties, object);
  return Qnil;
}

DEFUN ("set-text-properties", Fset_text_properties,
       Sset_text_properties, 3, 4, 0,
       doc: /* Completely replace properties of text from START to END.
The third argument PROPERTIES is the new property list.
If the optional fourth argument OBJECT is a buffer (or nil, which means
the current buffer), START and END are buffer positions (integers or
markers).  If OBJECT is a string, START and END are 0-based indices into it.
If PROPERTIES is nil, the effect is to remove all properties from
the designated part of OBJECT.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object properties, Lisp_Object object)
{
  return set_text_properties (start, end, properties, object, Qt);
}


DEFUN ("add-face-text-property", Fadd_face_text_property,
       Sadd_face_text_property, 3, 5, 0,
       doc: /* Add the face property to the text from START to END.
FACE specifies the face to add.  It should be a valid value of the
`face' property (typically a face name or a plist of face attributes
and values).

If any text in the region already has a non-nil `face' property, those
face(s) are retained.  This is done by setting the `face' property to
a list of faces, with FACE as the first element (by default) and the
pre-existing faces as the remaining elements.

If optional fourth argument APPEND is non-nil, append FACE to the end
of the face list instead.

If optional fifth argument OBJECT is a buffer (or nil, which means the
current buffer), START and END are buffer positions (integers or
markers).  If OBJECT is a string, START and END are 0-based indices
into it.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object face,
   Lisp_Object append, Lisp_Object object)
{
  AUTO_LIST2 (properties, Qface, face);
  add_text_properties_1 (start, end, properties, object,
			 (NILP (append)
			  ? TEXT_PROPERTY_PREPEND
			  : TEXT_PROPERTY_APPEND));
  return Qnil;
}

/* Replace properties of text from START to END with new list of
   properties PROPERTIES.  OBJECT is the buffer or string containing
   the text.  OBJECT nil means use the current buffer.
   COHERENT_CHANGE_P nil means this is being called as an internal
   subroutine, rather than as a change primitive with checking of
   read-only, invoking change hooks, etc..  Value is nil if the
   function _detected_ that it did not replace any properties, non-nil
   otherwise.  */

Lisp_Object
set_text_properties (Lisp_Object start, Lisp_Object end, Lisp_Object properties,
		     Lisp_Object object, Lisp_Object coherent_change_p)
{
  register INTERVAL i;
  Lisp_Object ostart, oend;

  ostart = start;
  oend = end;

  properties = validate_plist (properties);

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  /* If we want no properties for a whole string,
     get rid of its intervals.  */
  if (NILP (properties) && STRINGP (object)
      && XFASTINT (start) == 0
      && XFASTINT (end) == SCHARS (object))
    {
      if (!string_intervals (object))
	return Qnil;

      set_string_intervals (object, NULL);
      return Qt;
    }

  i = validate_interval_range (object, &start, &end, soft);

  if (!i)
    {
      /* If buffer has no properties, and we want none, return now.  */
      if (NILP (properties))
	return Qnil;

      /* Restore the original START and END values
	 because validate_interval_range increments them for strings.  */
      start = ostart;
      end = oend;

      i = validate_interval_range (object, &start, &end, hard);
      /* This can return if start == end.  */
      if (!i)
	return Qnil;
    }

  if (BUFFERP (object) && !NILP (coherent_change_p))
    modify_text_properties (object, start, end);

  set_text_properties_1 (start, end, properties, object, i);

  if (BUFFERP (object) && !NILP (coherent_change_p))
    signal_after_change (XINT (start), XINT (end) - XINT (start),
			 XINT (end) - XINT (start));
  return Qt;
}

/* Replace properties of text from START to END with new list of
   properties PROPERTIES.  OBJECT is the buffer or string containing
   the text.  This does not obey any hooks.
   You should provide the interval that START is located in as I.
   START and END can be in any order.  */

void
set_text_properties_1 (Lisp_Object start, Lisp_Object end, Lisp_Object properties, Lisp_Object object, INTERVAL i)
{
  register INTERVAL prev_changed = NULL;
  register ptrdiff_t s, len;
  INTERVAL unchanged;

  if (XINT (start) < XINT (end))
    {
      s = XINT (start);
      len = XINT (end) - s;
    }
  else if (XINT (end) < XINT (start))
    {
      s = XINT (end);
      len = XINT (start) - s;
    }
  else
    return;

  eassert (i);

  if (i->position != s)
    {
      unchanged = i;
      i = split_interval_right (unchanged, s - unchanged->position);

      if (LENGTH (i) > len)
	{
	  copy_properties (unchanged, i);
	  i = split_interval_left (i, len);
	  set_properties (properties, i, object);
	  return;
	}

      set_properties (properties, i, object);

      if (LENGTH (i) == len)
	return;

      prev_changed = i;
      len -= LENGTH (i);
      i = next_interval (i);
    }

  /* We are starting at the beginning of an interval I.  LEN is positive.  */
  do
    {
      eassert (i != 0);

      if (LENGTH (i) >= len)
	{
	  if (LENGTH (i) > len)
	    i = split_interval_left (i, len);

	  /* We have to call set_properties even if we are going to
	     merge the intervals, so as to make the undo records
	     and cause redisplay to happen.  */
	  set_properties (properties, i, object);
	  if (prev_changed)
	    merge_interval_left (i);
	  return;
	}

      len -= LENGTH (i);

      /* We have to call set_properties even if we are going to
	 merge the intervals, so as to make the undo records
	 and cause redisplay to happen.  */
      set_properties (properties, i, object);
      if (!prev_changed)
	prev_changed = i;
      else
	prev_changed = i = merge_interval_left (i);

      i = next_interval (i);
    }
  while (len > 0);
}

DEFUN ("remove-text-properties", Fremove_text_properties,
       Sremove_text_properties, 3, 4, 0,
       doc: /* Remove some properties from text from START to END.
The third argument PROPERTIES is a property list
whose property names specify the properties to remove.
\(The values stored in PROPERTIES are ignored.)
If the optional fourth argument OBJECT is a buffer (or nil, which means
the current buffer), START and END are buffer positions (integers or
markers).  If OBJECT is a string, START and END are 0-based indices into it.
Return t if any property was actually removed, nil otherwise.

Use `set-text-properties' if you want to remove all text properties.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object properties, Lisp_Object object)
{
  INTERVAL i, unchanged;
  ptrdiff_t s, len;
  bool modified = false;
  bool first_time = true;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

 retry:
  i = validate_interval_range (object, &start, &end, soft);
  if (!i)
    return Qnil;

  s = XINT (start);
  len = XINT (end) - s;

  /* If there are no properties on this entire interval, return.  */
  if (! interval_has_some_properties (properties, i))
    {
      ptrdiff_t got = LENGTH (i) - (s - i->position);

      do
	{
	  if (got >= len)
	    return Qnil;
	  len -= got;
	  i = next_interval (i);
	  got = LENGTH (i);
	}
      while (! interval_has_some_properties (properties, i));
    }
  /* Split away the beginning of this interval; what we don't
     want to modify.  */
  else if (i->position != s)
    {
      unchanged = i;
      i = split_interval_right (unchanged, s - unchanged->position);
      copy_properties (unchanged, i);
    }

  if (BUFFERP (object) && first_time)
    {
      ptrdiff_t prev_total_length = TOTAL_LENGTH (i);
      ptrdiff_t prev_pos = i->position;

      modify_text_properties (object, start, end);
      /* If someone called us recursively as a side effect of
	 modify_text_properties, and changed the intervals behind our back
	 (could happen if lock_file, called by prepare_to_modify_buffer,
	 triggers redisplay, and that calls add-text-properties again
	 in the same buffer), we cannot continue with I, because its
	 data changed.  So we restart the interval analysis anew.  */
      if (TOTAL_LENGTH (i) != prev_total_length
	  || i->position != prev_pos)
	{
	  first_time = false;
	  goto retry;
	}
    }

  /* We are at the beginning of an interval, with len to scan */
  for (;;)
    {
      eassert (i != 0);

      if (LENGTH (i) >= len)
	{
	  if (! interval_has_some_properties (properties, i))
	    {
	      eassert (modified);
	      if (BUFFERP (object))
		signal_after_change (XINT (start), XINT (end) - XINT (start),
				     XINT (end) - XINT (start));
	      return Qt;
	    }

	  if (LENGTH (i) == len)
	    {
	      remove_properties (properties, Qnil, i, object);
	      if (BUFFERP (object))
		signal_after_change (XINT (start), XINT (end) - XINT (start),
				     XINT (end) - XINT (start));
	      return Qt;
	    }

	  /* i has the properties, and goes past the change limit */
	  unchanged = i;
	  i = split_interval_left (i, len);
	  copy_properties (unchanged, i);
	  remove_properties (properties, Qnil, i, object);
	  if (BUFFERP (object))
	    signal_after_change (XINT (start), XINT (end) - XINT (start),
				 XINT (end) - XINT (start));
	  return Qt;
	}

      len -= LENGTH (i);
      modified |= remove_properties (properties, Qnil, i, object);
      i = next_interval (i);
    }
}

DEFUN ("remove-list-of-text-properties", Fremove_list_of_text_properties,
       Sremove_list_of_text_properties, 3, 4, 0,
       doc: /* Remove some properties from text from START to END.
The third argument LIST-OF-PROPERTIES is a list of property names to remove.
If the optional fourth argument OBJECT is a buffer (or nil, which means
the current buffer), START and END are buffer positions (integers or
markers).  If OBJECT is a string, START and END are 0-based indices into it.
Return t if any property was actually removed, nil otherwise.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object list_of_properties, Lisp_Object object)
{
  INTERVAL i, unchanged;
  ptrdiff_t s, len;
  bool modified = false;
  Lisp_Object properties;
  properties = list_of_properties;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

  i = validate_interval_range (object, &start, &end, soft);
  if (!i)
    return Qnil;

  s = XINT (start);
  len = XINT (end) - s;

  /* If there are no properties on the interval, return.  */
  if (! interval_has_some_properties_list (properties, i))
    {
      ptrdiff_t got = LENGTH (i) - (s - i->position);

      do
	{
	  if (got >= len)
	    return Qnil;
	  len -= got;
	  i = next_interval (i);
	  got = LENGTH (i);
	}
      while (! interval_has_some_properties_list (properties, i));
    }
  /* Split away the beginning of this interval; what we don't
     want to modify.  */
  else if (i->position != s)
    {
      unchanged = i;
      i = split_interval_right (unchanged, s - unchanged->position);
      copy_properties (unchanged, i);
    }

  /* We are at the beginning of an interval, with len to scan.
     The flag MODIFIED records if changes have been made.
     When object is a buffer, we must call modify_text_properties
     before changes are made and signal_after_change when we are done.
     Call modify_text_properties before calling remove_properties if !MODIFIED,
     and call signal_after_change before returning if MODIFIED. */
  for (;;)
    {
      eassert (i != 0);

      if (LENGTH (i) >= len)
	{
	  if (! interval_has_some_properties_list (properties, i))
	    {
	      if (modified)
		{
		  if (BUFFERP (object))
		    signal_after_change (XINT (start),
					 XINT (end) - XINT (start),
					 XINT (end) - XINT (start));
		  return Qt;
		}
	      else
		return Qnil;
	    }
	  else if (LENGTH (i) == len)
	    {
	      if (!modified && BUFFERP (object))
		modify_text_properties (object, start, end);
	      remove_properties (Qnil, properties, i, object);
	      if (BUFFERP (object))
		signal_after_change (XINT (start), XINT (end) - XINT (start),
				     XINT (end) - XINT (start));
	      return Qt;
	    }
	  else
	    { /* i has the properties, and goes past the change limit.  */
	      unchanged = i;
	      i = split_interval_left (i, len);
	      copy_properties (unchanged, i);
	      if (!modified && BUFFERP (object))
		modify_text_properties (object, start, end);
	      remove_properties (Qnil, properties, i, object);
	      if (BUFFERP (object))
		signal_after_change (XINT (start), XINT (end) - XINT (start),
				     XINT (end) - XINT (start));
	      return Qt;
	    }
	}
      if (interval_has_some_properties_list (properties, i))
	{
	  if (!modified && BUFFERP (object))
	    modify_text_properties (object, start, end);
	  remove_properties (Qnil, properties, i, object);
	  modified = true;
	}
      len -= LENGTH (i);
      i = next_interval (i);
      if (!i)
        {
          if (modified)
            {
              if (BUFFERP (object))
                signal_after_change (XINT (start),
                                     XINT (end) - XINT (start),
                                     XINT (end) - XINT (start));
              return Qt;
            }
          else
            return Qnil;
        }
    }
}
\f
DEFUN ("text-property-any", Ftext_property_any,
       Stext_property_any, 4, 5, 0,
       doc: /* Check text from START to END for property PROPERTY equaling VALUE.
If so, return the position of the first character whose property PROPERTY
is `eq' to VALUE.  Otherwise return nil.
If the optional fifth argument OBJECT is a buffer (or nil, which means
the current buffer), START and END are buffer positions (integers or
markers).  If OBJECT is a string, START and END are 0-based indices into it.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object property, Lisp_Object value, Lisp_Object object)
{
  register INTERVAL i;
  register ptrdiff_t e, pos;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);
  i = validate_interval_range (object, &start, &end, soft);
  if (!i)
    return (!NILP (value) || EQ (start, end) ? Qnil : start);
  e = XINT (end);

  while (i)
    {
      if (i->position >= e)
	break;
      if (EQ (textget (i->plist, property), value))
	{
	  pos = i->position;
	  if (pos < XINT (start))
	    pos = XINT (start);
	  return make_number (pos);
	}
      i = next_interval (i);
    }
  return Qnil;
}

DEFUN ("text-property-not-all", Ftext_property_not_all,
       Stext_property_not_all, 4, 5, 0,
       doc: /* Check text from START to END for property PROPERTY not equaling VALUE.
If so, return the position of the first character whose property PROPERTY
is not `eq' to VALUE.  Otherwise, return nil.
If the optional fifth argument OBJECT is a buffer (or nil, which means
the current buffer), START and END are buffer positions (integers or
markers).  If OBJECT is a string, START and END are 0-based indices into it.  */)
  (Lisp_Object start, Lisp_Object end, Lisp_Object property, Lisp_Object value, Lisp_Object object)
{
  register INTERVAL i;
  register ptrdiff_t s, e;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);
  i = validate_interval_range (object, &start, &end, soft);
  if (!i)
    return (NILP (value) || EQ (start, end)) ? Qnil : start;
  s = XINT (start);
  e = XINT (end);

  while (i)
    {
      if (i->position >= e)
	break;
      if (! EQ (textget (i->plist, property), value))
	{
	  if (i->position > s)
	    s = i->position;
	  return make_number (s);
	}
      i = next_interval (i);
    }
  return Qnil;
}

\f
/* Return the direction from which the text-property PROP would be
   inherited by any new text inserted at POS: 1 if it would be
   inherited from the char after POS, -1 if it would be inherited from
   the char before POS, and 0 if from neither.
   BUFFER can be either a buffer or nil (meaning current buffer).  */

int
text_property_stickiness (Lisp_Object prop, Lisp_Object pos, Lisp_Object buffer)
{
  bool ignore_previous_character;
  Lisp_Object prev_pos = make_number (XINT (pos) - 1);
  Lisp_Object front_sticky;
  bool is_rear_sticky = true, is_front_sticky = false; /* defaults */
  Lisp_Object defalt = Fassq (prop, Vtext_property_default_nonsticky);

  if (NILP (buffer))
    XSETBUFFER (buffer, current_buffer);

  ignore_previous_character = XINT (pos) <= BUF_BEGV (XBUFFER (buffer));

  if (ignore_previous_character || (CONSP (defalt) && !NILP (XCDR (defalt))))
    is_rear_sticky = false;
  else
    {
      Lisp_Object rear_non_sticky
	= Fget_text_property (prev_pos, Qrear_nonsticky, buffer);

      if (!NILP (CONSP (rear_non_sticky)
		 ? Fmemq (prop, rear_non_sticky)
		 : rear_non_sticky))
	/* PROP is rear-non-sticky.  */
	is_rear_sticky = false;
    }

  /* Consider following character.  */
  /* This signals an arg-out-of-range error if pos is outside the
     buffer's accessible range.  */
  front_sticky = Fget_text_property (pos, Qfront_sticky, buffer);

  if (EQ (front_sticky, Qt)
      || (CONSP (front_sticky)
	  && !NILP (Fmemq (prop, front_sticky))))
    /* PROP is inherited from after.  */
    is_front_sticky = true;

  /* Simple cases, where the properties are consistent.  */
  if (is_rear_sticky && !is_front_sticky)
    return -1;
  else if (!is_rear_sticky && is_front_sticky)
    return 1;
  else if (!is_rear_sticky && !is_front_sticky)
    return 0;

  /* The stickiness properties are inconsistent, so we have to
     disambiguate.  Basically, rear-sticky wins, _except_ if the
     property that would be inherited has a value of nil, in which case
     front-sticky wins.  */
  if (ignore_previous_character
      || NILP (Fget_text_property (prev_pos, prop, buffer)))
    return 1;
  else
    return -1;
}

\f
/* Copying properties between objects. */

/* Add properties from START to END of SRC, starting at POS in DEST.
   SRC and DEST may each refer to strings or buffers.
   Optional sixth argument PROP causes only that property to be copied.
   Properties are copied to DEST as if by `add-text-properties'.
   Return t if any property value actually changed, nil otherwise.  */

/* Note this can GC when DEST is a buffer.  */

Lisp_Object
copy_text_properties (Lisp_Object start, Lisp_Object end, Lisp_Object src,
		      Lisp_Object pos, Lisp_Object dest, Lisp_Object prop)
{
  INTERVAL i;
  Lisp_Object res;
  Lisp_Object stuff;
  Lisp_Object plist;
  ptrdiff_t s, e, e2, p, len;
  bool modified = false;

  i = validate_interval_range (src, &start, &end, soft);
  if (!i)
    return Qnil;

  CHECK_NUMBER_COERCE_MARKER (pos);
  {
    Lisp_Object dest_start, dest_end;

    e = XINT (pos) + (XINT (end) - XINT (start));
    if (MOST_POSITIVE_FIXNUM < e)
      args_out_of_range (pos, end);
    dest_start = pos;
    XSETFASTINT (dest_end, e);
    /* Apply this to a copy of pos; it will try to increment its arguments,
       which we don't want.  */
    validate_interval_range (dest, &dest_start, &dest_end, soft);
  }

  s = XINT (start);
  e = XINT (end);
  p = XINT (pos);

  stuff = Qnil;

  while (s < e)
    {
      e2 = i->position + LENGTH (i);
      if (e2 > e)
	e2 = e;
      len = e2 - s;

      plist = i->plist;
      if (! NILP (prop))
	while (! NILP (plist))
	  {
	    if (EQ (Fcar (plist), prop))
	      {
		plist = list2 (prop, Fcar (Fcdr (plist)));
		break;
	      }
	    plist = Fcdr (Fcdr (plist));
	  }
      if (! NILP (plist))
	/* Must defer modifications to the interval tree in case
	   src and dest refer to the same string or buffer.  */
	stuff = Fcons (list3 (make_number (p), make_number (p + len), plist),
		       stuff);

      i = next_interval (i);
      if (!i)
	break;

      p += len;
      s = i->position;
    }

  while (! NILP (stuff))
    {
      res = Fcar (stuff);
      res = Fadd_text_properties (Fcar (res), Fcar (Fcdr (res)),
				  Fcar (Fcdr (Fcdr (res))), dest);
      if (! NILP (res))
	modified = true;
      stuff = Fcdr (stuff);
    }

  return modified ? Qt : Qnil;
}


/* Return a list representing the text properties of OBJECT between
   START and END.  if PROP is non-nil, report only on that property.
   Each result list element has the form (S E PLIST), where S and E
   are positions in OBJECT and PLIST is a property list containing the
   text properties of OBJECT between S and E.  Value is nil if OBJECT
   doesn't contain text properties between START and END.  */

Lisp_Object
text_property_list (Lisp_Object object, Lisp_Object start, Lisp_Object end, Lisp_Object prop)
{
  struct interval *i;
  Lisp_Object result;

  result = Qnil;

  i = validate_interval_range (object, &start, &end, soft);
  if (i)
    {
      ptrdiff_t s = XINT (start);
      ptrdiff_t e = XINT (end);

      while (s < e)
	{
	  ptrdiff_t interval_end, len;
	  Lisp_Object plist;

	  interval_end = i->position + LENGTH (i);
	  if (interval_end > e)
	    interval_end = e;
	  len = interval_end - s;

	  plist = i->plist;

	  if (!NILP (prop))
	    for (; CONSP (plist); plist = Fcdr (XCDR (plist)))
	      if (EQ (XCAR (plist), prop))
		{
		  plist = list2 (prop, Fcar (XCDR (plist)));
		  break;
		}

	  if (!NILP (plist))
	    result = Fcons (list3 (make_number (s), make_number (s + len),
				   plist),
			    result);

	  i = next_interval (i);
	  if (!i)
	    break;
	  s = i->position;
	}
    }

  return result;
}


/* Add text properties to OBJECT from LIST.  LIST is a list of triples
   (START END PLIST), where START and END are positions and PLIST is a
   property list containing the text properties to add.  Adjust START
   and END positions by DELTA before adding properties.  */

void
add_text_properties_from_list (Lisp_Object object, Lisp_Object list, Lisp_Object delta)
{
  for (; CONSP (list); list = XCDR (list))
    {
      Lisp_Object item, start, end, plist;

      item = XCAR (list);
      start = make_number (XINT (XCAR (item)) + XINT (delta));
      end = make_number (XINT (XCAR (XCDR (item))) + XINT (delta));
      plist = XCAR (XCDR (XCDR (item)));

      Fadd_text_properties (start, end, plist, object);
    }
}



/* Modify end-points of ranges in LIST destructively, and return the
   new list.  LIST is a list as returned from text_property_list.
   Discard properties that begin at or after NEW_END, and limit
   end-points to NEW_END.  */

Lisp_Object
extend_property_ranges (Lisp_Object list, Lisp_Object old_end, Lisp_Object new_end)
{
  Lisp_Object prev = Qnil, head = list;
  ptrdiff_t max = XINT (new_end);

  for (; CONSP (list); prev = list, list = XCDR (list))
    {
      Lisp_Object item, beg;
      ptrdiff_t end;

      item = XCAR (list);
      beg = XCAR (item);
      end = XINT (XCAR (XCDR (item)));

      if (XINT (beg) >= max)
	{
	  /* The start-point is past the end of the new string.
	     Discard this property.  */
	  if (EQ (head, list))
	    head = XCDR (list);
	  else
	    XSETCDR (prev, XCDR (list));
	}
      else if ((end == XINT (old_end) && end != max)
	       || end > max)
	{
	  /* Either the end-point is past the end of the new string,
	     and we need to discard the properties past the new end,
	     or the caller is extending the property range, and we
	     should update all end-points that are on the old end of
	     the range to reflect that.  */
	  XSETCAR (XCDR (item), new_end);
	}
    }

  return head;
}


\f
/* Call the modification hook functions in LIST, each with START and END.  */

static void
call_mod_hooks (Lisp_Object list, Lisp_Object start, Lisp_Object end)
{
  while (!NILP (list))
    {
      call2 (Fcar (list), start, end);
      list = Fcdr (list);
    }
}

/* Check for read-only intervals between character positions START ... END,
   in BUF, and signal an error if we find one.

   Then check for any modification hooks in the range.
   Create a list of all these hooks in lexicographic order,
   eliminating consecutive extra copies of the same hook.  Then call
   those hooks in order, with START and END - 1 as arguments.  */

void
verify_interval_modification (struct buffer *buf,
			      ptrdiff_t start, ptrdiff_t end)
{
  INTERVAL intervals = buffer_intervals (buf);
  INTERVAL i;
  Lisp_Object hooks;
  Lisp_Object prev_mod_hooks;
  Lisp_Object mod_hooks;

  hooks = Qnil;
  prev_mod_hooks = Qnil;
  mod_hooks = Qnil;

  interval_insert_behind_hooks = Qnil;
  interval_insert_in_front_hooks = Qnil;

  if (!intervals)
    return;

  if (start > end)
    {
      ptrdiff_t temp = start;
      start = end;
      end = temp;
    }

  /* For an insert operation, check the two chars around the position.  */
  if (start == end)
    {
      INTERVAL prev = NULL;
      Lisp_Object before, after;

      /* Set I to the interval containing the char after START,
	 and PREV to the interval containing the char before START.
	 Either one may be null.  They may be equal.  */
      i = find_interval (intervals, start);

      if (start == BUF_BEGV (buf))
	prev = 0;
      else if (i->position == start)
	prev = previous_interval (i);
      else if (i->position < start)
	prev = i;
      if (start == BUF_ZV (buf))
	i = 0;

      /* If Vinhibit_read_only is set and is not a list, we can
	 skip the read_only checks.  */
      if (NILP (Vinhibit_read_only) || CONSP (Vinhibit_read_only))
	{
	  /* If I and PREV differ we need to check for the read-only
	     property together with its stickiness.  If either I or
	     PREV are 0, this check is all we need.
	     We have to take special care, since read-only may be
	     indirectly defined via the category property.  */
	  if (i != prev)
	    {
	      if (i)
		{
		  after = textget (i->plist, Qread_only);

		  /* If interval I is read-only and read-only is
		     front-sticky, inhibit insertion.
		     Check for read-only as well as category.  */
		  if (! NILP (after)
		      && NILP (Fmemq (after, Vinhibit_read_only)))
		    {
		      Lisp_Object tem;

		      tem = textget (i->plist, Qfront_sticky);
		      if (TMEM (Qread_only, tem)
			  || (NILP (Fplist_get (i->plist, Qread_only))
			      && TMEM (Qcategory, tem)))
			text_read_only (after);
		    }
		}

	      if (prev)
		{
		  before = textget (prev->plist, Qread_only);

		  /* If interval PREV is read-only and read-only isn't
		     rear-nonsticky, inhibit insertion.
		     Check for read-only as well as category.  */
		  if (! NILP (before)
		      && NILP (Fmemq (before, Vinhibit_read_only)))
		    {
		      Lisp_Object tem;

		      tem = textget (prev->plist, Qrear_nonsticky);
		      if (! TMEM (Qread_only, tem)
			  && (! NILP (Fplist_get (prev->plist,Qread_only))
			      || ! TMEM (Qcategory, tem)))
			text_read_only (before);
		    }
		}
	    }
	  else if (i)
	    {
	      after = textget (i->plist, Qread_only);

	      /* If interval I is read-only and read-only is
		 front-sticky, inhibit insertion.
		 Check for read-only as well as category.  */
	      if (! NILP (after) && NILP (Fmemq (after, Vinhibit_read_only)))
		{
		  Lisp_Object tem;

		  tem = textget (i->plist, Qfront_sticky);
		  if (TMEM (Qread_only, tem)
		      || (NILP (Fplist_get (i->plist, Qread_only))
			  && TMEM (Qcategory, tem)))
		    text_read_only (after);

		  tem = textget (prev->plist, Qrear_nonsticky);
		  if (! TMEM (Qread_only, tem)
		      && (! NILP (Fplist_get (prev->plist, Qread_only))
			  || ! TMEM (Qcategory, tem)))
		    text_read_only (after);
		}
	    }
	}

      /* Run both insert hooks (just once if they're the same).  */
      if (prev)
	interval_insert_behind_hooks
	  = textget (prev->plist, Qinsert_behind_hooks);
      if (i)
	interval_insert_in_front_hooks
	  = textget (i->plist, Qinsert_in_front_hooks);
    }
  else
    {
      /* Loop over intervals on or next to START...END,
	 collecting their hooks.  */

      i = find_interval (intervals, start);
      do
	{
	  if (! INTERVAL_WRITABLE_P (i))
	    text_read_only (textget (i->plist, Qread_only));

	  if (!inhibit_modification_hooks)
	    {
	      mod_hooks = textget (i->plist, Qmodification_hooks);
	      if (! NILP (mod_hooks) && ! EQ (mod_hooks, prev_mod_hooks))
		{
		  hooks = Fcons (mod_hooks, hooks);
		  prev_mod_hooks = mod_hooks;
		}
	    }

	  if (i->position + LENGTH (i) < end
	      && (!NILP (BVAR (current_buffer, read_only))
		  && NILP (Vinhibit_read_only)))
	    xsignal1 (Qbuffer_read_only, Fcurrent_buffer ());

	  i = next_interval (i);
	}
      /* Keep going thru the interval containing the char before END.  */
      while (i && i->position < end);

      if (!inhibit_modification_hooks)
	{
	  hooks = Fnreverse (hooks);
	  while (! EQ (hooks, Qnil))
	    {
	      call_mod_hooks (Fcar (hooks), make_number (start),
			      make_number (end));
	      hooks = Fcdr (hooks);
	    }
	}
    }
}

/* Run the interval hooks for an insertion on character range START ... END.
   verify_interval_modification chose which hooks to run;
   this function is called after the insertion happens
   so it can indicate the range of inserted text.  */

void
report_interval_modification (Lisp_Object start, Lisp_Object end)
{
  if (! NILP (interval_insert_behind_hooks))
    call_mod_hooks (interval_insert_behind_hooks, start, end);
  if (! NILP (interval_insert_in_front_hooks)
      && ! EQ (interval_insert_in_front_hooks,
	       interval_insert_behind_hooks))
    call_mod_hooks (interval_insert_in_front_hooks, start, end);
}
\f
void
syms_of_textprop (void)
{
  DEFVAR_LISP ("default-text-properties", Vdefault_text_properties,
	       doc: /* Property-list used as default values.
The value of a property in this list is seen as the value for every
character that does not have its own value for that property.  */);
  Vdefault_text_properties = Qnil;

  DEFVAR_LISP ("char-property-alias-alist", Vchar_property_alias_alist,
	       doc: /* Alist of alternative properties for properties without a value.
Each element should look like (PROPERTY ALTERNATIVE1 ALTERNATIVE2...).
If a piece of text has no direct value for a particular property, then
this alist is consulted.  If that property appears in the alist, then
the first non-nil value from the associated alternative properties is
returned. */);
  Vchar_property_alias_alist = Qnil;

  DEFVAR_LISP ("inhibit-point-motion-hooks", Vinhibit_point_motion_hooks,
	       doc: /* If non-nil, don't run `point-left' and `point-entered' text properties.
This also inhibits the use of the `intangible' text property.

This variable is obsolete since Emacs-25.1.  Use `cursor-intangible-mode'
or `cursor-sensor-mode' instead.  */);
  /* FIXME: We should make-obsolete-variable, but that signals too many
     warnings in code which does (let ((inhibit-point-motion-hooks t)) ...)
     Ideally, make-obsolete-variable should let us specify that only the nil
     value is obsolete, but that requires too many changes in bytecomp.el,
     so for now we'll keep it "obsolete via the docstring".  */
  Vinhibit_point_motion_hooks = Qt;

  DEFVAR_LISP ("text-property-default-nonsticky",
	       Vtext_property_default_nonsticky,
	       doc: /* Alist of properties vs the corresponding non-stickiness.
Each element has the form (PROPERTY . NONSTICKINESS).

If a character in a buffer has PROPERTY, new text inserted adjacent to
the character doesn't inherit PROPERTY if NONSTICKINESS is non-nil,
inherits it if NONSTICKINESS is nil.  The `front-sticky' and
`rear-nonsticky' properties of the character override NONSTICKINESS.  */);
  /* Text properties `syntax-table'and `display' should be nonsticky
     by default.  */
  Vtext_property_default_nonsticky
    = list2 (Fcons (Qsyntax_table, Qt), Fcons (Qdisplay, Qt));

  staticpro (&interval_insert_behind_hooks, Qnil);
  staticpro (&interval_insert_in_front_hooks, Qnil);


  /* Common attributes one might give text.  */

  DEFSYM (Qfont, "font");
  DEFSYM (Qface, "face");
  DEFSYM (Qread_only, "read-only");
  DEFSYM (Qinvisible, "invisible");
  DEFSYM (Qintangible, "intangible");
  DEFSYM (Qcategory, "category");
  DEFSYM (Qlocal_map, "local-map");
  DEFSYM (Qfront_sticky, "front-sticky");
  DEFSYM (Qrear_nonsticky, "rear-nonsticky");
  DEFSYM (Qmouse_face, "mouse-face");
  DEFSYM (Qminibuffer_prompt, "minibuffer-prompt");

  /* Properties that text might use to specify certain actions.  */

  DEFSYM (Qpoint_left, "point-left");
  DEFSYM (Qpoint_entered, "point-entered");

  defsubr (&Stext_properties_at);
  defsubr (&Sget_text_property);
  defsubr (&Sget_char_property);
  defsubr (&Sget_char_property_and_overlay);
  defsubr (&Snext_char_property_change);
  defsubr (&Sprevious_char_property_change);
  defsubr (&Snext_single_char_property_change);
  defsubr (&Sprevious_single_char_property_change);
  defsubr (&Snext_property_change);
  defsubr (&Snext_single_property_change);
  defsubr (&Sprevious_property_change);
  defsubr (&Sprevious_single_property_change);
  defsubr (&Sadd_text_properties);
  defsubr (&Sput_text_property);
  defsubr (&Sset_text_properties);
  defsubr (&Sadd_face_text_property);
  defsubr (&Sremove_text_properties);
  defsubr (&Sremove_list_of_text_properties);
  defsubr (&Stext_property_any);
  defsubr (&Stext_property_not_all);
}

debug log:

solving 7f7d7359ffc ...
found 7f7d7359ffc in https://yhetil.org/emacs/CAOqdjBe72ZftDH4TMHB9D2uKXXoqaPW-dVXwLs3+2nzwXqqUrA@mail.gmail.com/
found 984f2e66406 in https://git.savannah.gnu.org/cgit/emacs.git
preparing index
index prepared:
100644 984f2e664061dfd526d3c1765eb60c905c329dff	src/textprop.c

applying [1/1] https://yhetil.org/emacs/CAOqdjBe72ZftDH4TMHB9D2uKXXoqaPW-dVXwLs3+2nzwXqqUrA@mail.gmail.com/
diff --git a/src/textprop.c b/src/textprop.c
index 984f2e66406..7f7d7359ffc 100644

Checking patch src/textprop.c...
Applied patch src/textprop.c cleanly.

index at:
100644 7f7d7359ffc21e36307b16cac31ea84cd4557971	src/textprop.c

(*) Git path names are given by the tree(s) the blob belongs to.
    Blobs themselves have no identifier aside from the hash of its contents.^

Code repositories for project(s) associated with this external index

	https://git.savannah.gnu.org/cgit/emacs.git
	https://git.savannah.gnu.org/cgit/emacs/org-mode.git

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.