aboutsummaryrefslogtreecommitdiff
path: root/gdb/linux-tdep.c
blob: 459386f2596e960997bb7ad8e1886ab98e3bb7d6 (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
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
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
/* Target-dependent code for GNU/Linux, architecture independent.

   Copyright (C) 2009-2017 Free Software Foundation, Inc.

   This file is part of GDB.

   This program 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.

   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "gdbtypes.h"
#include "linux-tdep.h"
#include "auxv.h"
#include "target.h"
#include "gdbthread.h"
#include "gdbcore.h"
#include "regcache.h"
#include "regset.h"
#include "elf/common.h"
#include "elf-bfd.h"            /* for elfcore_write_* */
#include "inferior.h"
#include "cli/cli-utils.h"
#include "arch-utils.h"
#include "gdb_obstack.h"
#include "observer.h"
#include "objfiles.h"
#include "infcall.h"
#include "gdbcmd.h"
#include "gdb_regex.h"
#include "common/enum-flags.h"
#include "common/gdb_optional.h"

#include <ctype.h>

/* This enum represents the values that the user can choose when
   informing the Linux kernel about which memory mappings will be
   dumped in a corefile.  They are described in the file
   Documentation/filesystems/proc.txt, inside the Linux kernel
   tree.  */

enum filter_flag
  {
    COREFILTER_ANON_PRIVATE = 1 << 0,
    COREFILTER_ANON_SHARED = 1 << 1,
    COREFILTER_MAPPED_PRIVATE = 1 << 2,
    COREFILTER_MAPPED_SHARED = 1 << 3,
    COREFILTER_ELF_HEADERS = 1 << 4,
    COREFILTER_HUGETLB_PRIVATE = 1 << 5,
    COREFILTER_HUGETLB_SHARED = 1 << 6,
  };
DEF_ENUM_FLAGS_TYPE (enum filter_flag, filter_flags);

/* This struct is used to map flags found in the "VmFlags:" field (in
   the /proc/<PID>/smaps file).  */

struct smaps_vmflags
  {
    /* Zero if this structure has not been initialized yet.  It
       probably means that the Linux kernel being used does not emit
       the "VmFlags:" field on "/proc/PID/smaps".  */

    unsigned int initialized_p : 1;

    /* Memory mapped I/O area (VM_IO, "io").  */

    unsigned int io_page : 1;

    /* Area uses huge TLB pages (VM_HUGETLB, "ht").  */

    unsigned int uses_huge_tlb : 1;

    /* Do not include this memory region on the coredump (VM_DONTDUMP, "dd").  */

    unsigned int exclude_coredump : 1;

    /* Is this a MAP_SHARED mapping (VM_SHARED, "sh").  */

    unsigned int shared_mapping : 1;
  };

/* Whether to take the /proc/PID/coredump_filter into account when
   generating a corefile.  */

static int use_coredump_filter = 1;

/* This enum represents the signals' numbers on a generic architecture
   running the Linux kernel.  The definition of "generic" comes from
   the file <include/uapi/asm-generic/signal.h>, from the Linux kernel
   tree, which is the "de facto" implementation of signal numbers to
   be used by new architecture ports.

   For those architectures which have differences between the generic
   standard (e.g., Alpha), we define the different signals (and *only*
   those) in the specific target-dependent file (e.g.,
   alpha-linux-tdep.c, for Alpha).  Please refer to the architecture's
   tdep file for more information.

   ARM deserves a special mention here.  On the file
   <arch/arm/include/uapi/asm/signal.h>, it defines only one different
   (and ARM-only) signal, which is SIGSWI, with the same number as
   SIGRTMIN.  This signal is used only for a very specific target,
   called ArthurOS (from RISCOS).  Therefore, we do not handle it on
   the ARM-tdep file, and we can safely use the generic signal handler
   here for ARM targets.

   As stated above, this enum is derived from
   <include/uapi/asm-generic/signal.h>, from the Linux kernel
   tree.  */

enum
  {
    LINUX_SIGHUP = 1,
    LINUX_SIGINT = 2,
    LINUX_SIGQUIT = 3,
    LINUX_SIGILL = 4,
    LINUX_SIGTRAP = 5,
    LINUX_SIGABRT = 6,
    LINUX_SIGIOT = 6,
    LINUX_SIGBUS = 7,
    LINUX_SIGFPE = 8,
    LINUX_SIGKILL = 9,
    LINUX_SIGUSR1 = 10,
    LINUX_SIGSEGV = 11,
    LINUX_SIGUSR2 = 12,
    LINUX_SIGPIPE = 13,
    LINUX_SIGALRM = 14,
    LINUX_SIGTERM = 15,
    LINUX_SIGSTKFLT = 16,
    LINUX_SIGCHLD = 17,
    LINUX_SIGCONT = 18,
    LINUX_SIGSTOP = 19,
    LINUX_SIGTSTP = 20,
    LINUX_SIGTTIN = 21,
    LINUX_SIGTTOU = 22,
    LINUX_SIGURG = 23,
    LINUX_SIGXCPU = 24,
    LINUX_SIGXFSZ = 25,
    LINUX_SIGVTALRM = 26,
    LINUX_SIGPROF = 27,
    LINUX_SIGWINCH = 28,
    LINUX_SIGIO = 29,
    LINUX_SIGPOLL = LINUX_SIGIO,
    LINUX_SIGPWR = 30,
    LINUX_SIGSYS = 31,
    LINUX_SIGUNUSED = 31,

    LINUX_SIGRTMIN = 32,
    LINUX_SIGRTMAX = 64,
  };

static struct gdbarch_data *linux_gdbarch_data_handle;

struct linux_gdbarch_data
  {
    struct type *siginfo_type;
  };

static void *
init_linux_gdbarch_data (struct gdbarch *gdbarch)
{
  return GDBARCH_OBSTACK_ZALLOC (gdbarch, struct linux_gdbarch_data);
}

static struct linux_gdbarch_data *
get_linux_gdbarch_data (struct gdbarch *gdbarch)
{
  return ((struct linux_gdbarch_data *)
	  gdbarch_data (gdbarch, linux_gdbarch_data_handle));
}

/* Per-inferior data key.  */
static const struct inferior_data *linux_inferior_data;

/* Linux-specific cached data.  This is used by GDB for caching
   purposes for each inferior.  This helps reduce the overhead of
   transfering data from a remote target to the local host.  */
struct linux_info
{
  /* Cache of the inferior's vsyscall/vDSO mapping range.  Only valid
     if VSYSCALL_RANGE_P is positive.  This is cached because getting
     at this info requires an auxv lookup (which is itself cached),
     and looking through the inferior's mappings (which change
     throughout execution and therefore cannot be cached).  */
  struct mem_range vsyscall_range;

  /* Zero if we haven't tried looking up the vsyscall's range before
     yet.  Positive if we tried looking it up, and found it.  Negative
     if we tried looking it up but failed.  */
  int vsyscall_range_p;
};

/* Frees whatever allocated space there is to be freed and sets INF's
   linux cache data pointer to NULL.  */

static void
invalidate_linux_cache_inf (struct inferior *inf)
{
  struct linux_info *info;

  info = (struct linux_info *) inferior_data (inf, linux_inferior_data);
  if (info != NULL)
    {
      xfree (info);
      set_inferior_data (inf, linux_inferior_data, NULL);
    }
}

/* Handles the cleanup of the linux cache for inferior INF.  ARG is
   ignored.  Callback for the inferior_appeared and inferior_exit
   events.  */

static void
linux_inferior_data_cleanup (struct inferior *inf, void *arg)
{
  invalidate_linux_cache_inf (inf);
}

/* Fetch the linux cache info for INF.  This function always returns a
   valid INFO pointer.  */

static struct linux_info *
get_linux_inferior_data (void)
{
  struct linux_info *info;
  struct inferior *inf = current_inferior ();

  info = (struct linux_info *) inferior_data (inf, linux_inferior_data);
  if (info == NULL)
    {
      info = XCNEW (struct linux_info);
      set_inferior_data (inf, linux_inferior_data, info);
    }

  return info;
}

/* See linux-tdep.h.  */

struct type *
linux_get_siginfo_type_with_fields (struct gdbarch *gdbarch,
				    linux_siginfo_extra_fields extra_fields)
{
  struct linux_gdbarch_data *linux_gdbarch_data;
  struct type *int_type, *uint_type, *long_type, *void_ptr_type, *short_type;
  struct type *uid_type, *pid_type;
  struct type *sigval_type, *clock_type;
  struct type *siginfo_type, *sifields_type;
  struct type *type;

  linux_gdbarch_data = get_linux_gdbarch_data (gdbarch);
  if (linux_gdbarch_data->siginfo_type != NULL)
    return linux_gdbarch_data->siginfo_type;

  int_type = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch),
			 	0, "int");
  uint_type = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch),
				 1, "unsigned int");
  long_type = arch_integer_type (gdbarch, gdbarch_long_bit (gdbarch),
				 0, "long");
  short_type = arch_integer_type (gdbarch, gdbarch_long_bit (gdbarch),
				 0, "short");
  void_ptr_type = lookup_pointer_type (builtin_type (gdbarch)->builtin_void);

  /* sival_t */
  sigval_type = arch_composite_type (gdbarch, NULL, TYPE_CODE_UNION);
  TYPE_NAME (sigval_type) = xstrdup ("sigval_t");
  append_composite_type_field (sigval_type, "sival_int", int_type);
  append_composite_type_field (sigval_type, "sival_ptr", void_ptr_type);

  /* __pid_t */
  pid_type = arch_type (gdbarch, TYPE_CODE_TYPEDEF,
			TYPE_LENGTH (int_type) * TARGET_CHAR_BIT, "__pid_t");
  TYPE_TARGET_TYPE (pid_type) = int_type;
  TYPE_TARGET_STUB (pid_type) = 1;

  /* __uid_t */
  uid_type = arch_type (gdbarch, TYPE_CODE_TYPEDEF,
			TYPE_LENGTH (uint_type) * TARGET_CHAR_BIT, "__uid_t");
  TYPE_TARGET_TYPE (uid_type) = uint_type;
  TYPE_TARGET_STUB (uid_type) = 1;

  /* __clock_t */
  clock_type = arch_type (gdbarch, TYPE_CODE_TYPEDEF,
			  TYPE_LENGTH (long_type) * TARGET_CHAR_BIT,
			  "__clock_t");
  TYPE_TARGET_TYPE (clock_type) = long_type;
  TYPE_TARGET_STUB (clock_type) = 1;

  /* _sifields */
  sifields_type = arch_composite_type (gdbarch, NULL, TYPE_CODE_UNION);

  {
    const int si_max_size = 128;
    int si_pad_size;
    int size_of_int = gdbarch_int_bit (gdbarch) / HOST_CHAR_BIT;

    /* _pad */
    if (gdbarch_ptr_bit (gdbarch) == 64)
      si_pad_size = (si_max_size / size_of_int) - 4;
    else
      si_pad_size = (si_max_size / size_of_int) - 3;
    append_composite_type_field (sifields_type, "_pad",
				 init_vector_type (int_type, si_pad_size));
  }

  /* _kill */
  type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
  append_composite_type_field (type, "si_pid", pid_type);
  append_composite_type_field (type, "si_uid", uid_type);
  append_composite_type_field (sifields_type, "_kill", type);

  /* _timer */
  type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
  append_composite_type_field (type, "si_tid", int_type);
  append_composite_type_field (type, "si_overrun", int_type);
  append_composite_type_field (type, "si_sigval", sigval_type);
  append_composite_type_field (sifields_type, "_timer", type);

  /* _rt */
  type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
  append_composite_type_field (type, "si_pid", pid_type);
  append_composite_type_field (type, "si_uid", uid_type);
  append_composite_type_field (type, "si_sigval", sigval_type);
  append_composite_type_field (sifields_type, "_rt", type);

  /* _sigchld */
  type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
  append_composite_type_field (type, "si_pid", pid_type);
  append_composite_type_field (type, "si_uid", uid_type);
  append_composite_type_field (type, "si_status", int_type);
  append_composite_type_field (type, "si_utime", clock_type);
  append_composite_type_field (type, "si_stime", clock_type);
  append_composite_type_field (sifields_type, "_sigchld", type);

  /* _sigfault */
  type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
  append_composite_type_field (type, "si_addr", void_ptr_type);

  /* Additional bound fields for _sigfault in case they were requested.  */
  if ((extra_fields & LINUX_SIGINFO_FIELD_ADDR_BND) != 0)
    {
      struct type *sigfault_bnd_fields;

      append_composite_type_field (type, "_addr_lsb", short_type);
      sigfault_bnd_fields = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
      append_composite_type_field (sigfault_bnd_fields, "_lower", void_ptr_type);
      append_composite_type_field (sigfault_bnd_fields, "_upper", void_ptr_type);
      append_composite_type_field (type, "_addr_bnd", sigfault_bnd_fields);
    }
  append_composite_type_field (sifields_type, "_sigfault", type);

  /* _sigpoll */
  type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
  append_composite_type_field (type, "si_band", long_type);
  append_composite_type_field (type, "si_fd", int_type);
  append_composite_type_field (sifields_type, "_sigpoll", type);

  /* struct siginfo */
  siginfo_type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT);
  TYPE_NAME (siginfo_type) = xstrdup ("siginfo");
  append_composite_type_field (siginfo_type, "si_signo", int_type);
  append_composite_type_field (siginfo_type, "si_errno", int_type);
  append_composite_type_field (siginfo_type, "si_code", int_type);
  append_composite_type_field_aligned (siginfo_type,
				       "_sifields", sifields_type,
				       TYPE_LENGTH (long_type));

  linux_gdbarch_data->siginfo_type = siginfo_type;

  return siginfo_type;
}

/* This function is suitable for architectures that don't
   extend/override the standard siginfo structure.  */

static struct type *
linux_get_siginfo_type (struct gdbarch *gdbarch)
{
  return linux_get_siginfo_type_with_fields (gdbarch, 0);
}

/* Return true if the target is running on uClinux instead of normal
   Linux kernel.  */

int
linux_is_uclinux (void)
{
  CORE_ADDR dummy;

  return (target_auxv_search (&current_target, AT_NULL, &dummy) > 0
	  && target_auxv_search (&current_target, AT_PAGESZ, &dummy) == 0);
}

static int
linux_has_shared_address_space (struct gdbarch *gdbarch)
{
  return linux_is_uclinux ();
}

/* This is how we want PTIDs from core files to be printed.  */

static const char *
linux_core_pid_to_str (struct gdbarch *gdbarch, ptid_t ptid)
{
  static char buf[80];

  if (ptid_get_lwp (ptid) != 0)
    {
      snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid));
      return buf;
    }

  return normal_pid_to_str (ptid);
}

/* Service function for corefiles and info proc.  */

static void
read_mapping (const char *line,
	      ULONGEST *addr, ULONGEST *endaddr,
	      const char **permissions, size_t *permissions_len,
	      ULONGEST *offset,
              const char **device, size_t *device_len,
	      ULONGEST *inode,
	      const char **filename)
{
  const char *p = line;

  *addr = strtoulst (p, &p, 16);
  if (*p == '-')
    p++;
  *endaddr = strtoulst (p, &p, 16);

  p = skip_spaces (p);
  *permissions = p;
  while (*p && !isspace (*p))
    p++;
  *permissions_len = p - *permissions;

  *offset = strtoulst (p, &p, 16);

  p = skip_spaces (p);
  *device = p;
  while (*p && !isspace (*p))
    p++;
  *device_len = p - *device;

  *inode = strtoulst (p, &p, 10);

  p = skip_spaces (p);
  *filename = p;
}

/* Helper function to decode the "VmFlags" field in /proc/PID/smaps.

   This function was based on the documentation found on
   <Documentation/filesystems/proc.txt>, on the Linux kernel.

   Linux kernels before commit
   834f82e2aa9a8ede94b17b656329f850c1471514 (3.10) do not have this
   field on smaps.  */

static void
decode_vmflags (char *p, struct smaps_vmflags *v)
{
  char *saveptr = NULL;
  const char *s;

  v->initialized_p = 1;
  p = skip_to_space (p);
  p = skip_spaces (p);

  for (s = strtok_r (p, " ", &saveptr);
       s != NULL;
       s = strtok_r (NULL, " ", &saveptr))
    {
      if (strcmp (s, "io") == 0)
	v->io_page = 1;
      else if (strcmp (s, "ht") == 0)
	v->uses_huge_tlb = 1;
      else if (strcmp (s, "dd") == 0)
	v->exclude_coredump = 1;
      else if (strcmp (s, "sh") == 0)
	v->shared_mapping = 1;
    }
}

/* Regexes used by mapping_is_anonymous_p.  Put in a structure because
   they're initialized lazily.  */

struct mapping_regexes
{
  /* Matches "/dev/zero" filenames (with or without the "(deleted)"
     string in the end).  We know for sure, based on the Linux kernel
     code, that memory mappings whose associated filename is
     "/dev/zero" are guaranteed to be MAP_ANONYMOUS.  */
  compiled_regex dev_zero
    {"^/dev/zero\\( (deleted)\\)\\?$", REG_NOSUB,
     _("Could not compile regex to match /dev/zero filename")};

  /* Matches "/SYSV%08x" filenames (with or without the "(deleted)"
     string in the end).  These filenames refer to shared memory
     (shmem), and memory mappings associated with them are
     MAP_ANONYMOUS as well.  */
  compiled_regex shmem_file
    {"^/\\?SYSV[0-9a-fA-F]\\{8\\}\\( (deleted)\\)\\?$", REG_NOSUB,
     _("Could not compile regex to match shmem filenames")};

  /* A heuristic we use to try to mimic the Linux kernel's 'n_link ==
     0' code, which is responsible to decide if it is dealing with a
     'MAP_SHARED | MAP_ANONYMOUS' mapping.  In other words, if
     FILE_DELETED matches, it does not necessarily mean that we are
     dealing with an anonymous shared mapping.  However, there is no
     easy way to detect this currently, so this is the best
     approximation we have.

     As a result, GDB will dump readonly pages of deleted executables
     when using the default value of coredump_filter (0x33), while the
     Linux kernel will not dump those pages.  But we can live with
     that.  */
  compiled_regex file_deleted
    {" (deleted)$", REG_NOSUB,
     _("Could not compile regex to match '<file> (deleted)'")};
};

/* Return 1 if the memory mapping is anonymous, 0 otherwise.

   FILENAME is the name of the file present in the first line of the
   memory mapping, in the "/proc/PID/smaps" output.  For example, if
   the first line is:

   7fd0ca877000-7fd0d0da0000 r--p 00000000 fd:02 2100770   /path/to/file

   Then FILENAME will be "/path/to/file".  */

static int
mapping_is_anonymous_p (const char *filename)
{
  static gdb::optional<mapping_regexes> regexes;
  static int init_regex_p = 0;

  if (!init_regex_p)
    {
      /* Let's be pessimistic and assume there will be an error while
	 compiling the regex'es.  */
      init_regex_p = -1;

      regexes.emplace ();

      /* If we reached this point, then everything succeeded.  */
      init_regex_p = 1;
    }

  if (init_regex_p == -1)
    {
      const char deleted[] = " (deleted)";
      size_t del_len = sizeof (deleted) - 1;
      size_t filename_len = strlen (filename);

      /* There was an error while compiling the regex'es above.  In
	 order to try to give some reliable information to the caller,
	 we just try to find the string " (deleted)" in the filename.
	 If we managed to find it, then we assume the mapping is
	 anonymous.  */
      return (filename_len >= del_len
	      && strcmp (filename + filename_len - del_len, deleted) == 0);
    }

  if (*filename == '\0'
      || regexes->dev_zero.exec (filename, 0, NULL, 0) == 0
      || regexes->shmem_file.exec (filename, 0, NULL, 0) == 0
      || regexes->file_deleted.exec (filename, 0, NULL, 0) == 0)
    return 1;

  return 0;
}

/* Return 0 if the memory mapping (which is related to FILTERFLAGS, V,
   MAYBE_PRIVATE_P, and MAPPING_ANONYMOUS_P) should not be dumped, or
   greater than 0 if it should.

   In a nutshell, this is the logic that we follow in order to decide
   if a mapping should be dumped or not.

   - If the mapping is associated to a file whose name ends with
     " (deleted)", or if the file is "/dev/zero", or if it is
     "/SYSV%08x" (shared memory), or if there is no file associated
     with it, or if the AnonHugePages: or the Anonymous: fields in the
     /proc/PID/smaps have contents, then GDB considers this mapping to
     be anonymous.  Otherwise, GDB considers this mapping to be a
     file-backed mapping (because there will be a file associated with
     it).
 
     It is worth mentioning that, from all those checks described
     above, the most fragile is the one to see if the file name ends
     with " (deleted)".  This does not necessarily mean that the
     mapping is anonymous, because the deleted file associated with
     the mapping may have been a hard link to another file, for
     example.  The Linux kernel checks to see if "i_nlink == 0", but
     GDB cannot easily (and normally) do this check (iff running as
     root, it could find the mapping in /proc/PID/map_files/ and
     determine whether there still are other hard links to the
     inode/file).  Therefore, we made a compromise here, and we assume
     that if the file name ends with " (deleted)", then the mapping is
     indeed anonymous.  FWIW, this is something the Linux kernel could
     do better: expose this information in a more direct way.
 
   - If we see the flag "sh" in the "VmFlags:" field (in
     /proc/PID/smaps), then certainly the memory mapping is shared
     (VM_SHARED).  If we have access to the VmFlags, and we don't see
     the "sh" there, then certainly the mapping is private.  However,
     Linux kernels before commit
     834f82e2aa9a8ede94b17b656329f850c1471514 (3.10) do not have the
     "VmFlags:" field; in that case, we use another heuristic: if we
     see 'p' in the permission flags, then we assume that the mapping
     is private, even though the presence of the 's' flag there would
     mean VM_MAYSHARE, which means the mapping could still be private.
     This should work OK enough, however.  */

static int
dump_mapping_p (filter_flags filterflags, const struct smaps_vmflags *v,
		int maybe_private_p, int mapping_anon_p, int mapping_file_p,
		const char *filename)
{
  /* Initially, we trust in what we received from our caller.  This
     value may not be very precise (i.e., it was probably gathered
     from the permission line in the /proc/PID/smaps list, which
     actually refers to VM_MAYSHARE, and not VM_SHARED), but it is
     what we have until we take a look at the "VmFlags:" field
     (assuming that the version of the Linux kernel being used
     supports it, of course).  */
  int private_p = maybe_private_p;

  /* We always dump vDSO and vsyscall mappings, because it's likely that
     there'll be no file to read the contents from at core load time.
     The kernel does the same.  */
  if (strcmp ("[vdso]", filename) == 0
      || strcmp ("[vsyscall]", filename) == 0)
    return 1;

  if (v->initialized_p)
    {
      /* We never dump I/O mappings.  */
      if (v->io_page)
	return 0;

      /* Check if we should exclude this mapping.  */
      if (v->exclude_coredump)
	return 0;

      /* Update our notion of whether this mapping is shared or
	 private based on a trustworthy value.  */
      private_p = !v->shared_mapping;

      /* HugeTLB checking.  */
      if (v->uses_huge_tlb)
	{
	  if ((private_p && (filterflags & COREFILTER_HUGETLB_PRIVATE))
	      || (!private_p && (filterflags & COREFILTER_HUGETLB_SHARED)))
	    return 1;

	  return 0;
	}
    }

  if (private_p)
    {
      if (mapping_anon_p && mapping_file_p)
	{
	  /* This is a special situation.  It can happen when we see a
	     mapping that is file-backed, but that contains anonymous
	     pages.  */
	  return ((filterflags & COREFILTER_ANON_PRIVATE) != 0
		  || (filterflags & COREFILTER_MAPPED_PRIVATE) != 0);
	}
      else if (mapping_anon_p)
	return (filterflags & COREFILTER_ANON_PRIVATE) != 0;
      else
	return (filterflags & COREFILTER_MAPPED_PRIVATE) != 0;
    }
  else
    {
      if (mapping_anon_p && mapping_file_p)
	{
	  /* This is a special situation.  It can happen when we see a
	     mapping that is file-backed, but that contains anonymous
	     pages.  */
	  return ((filterflags & COREFILTER_ANON_SHARED) != 0
		  || (filterflags & COREFILTER_MAPPED_SHARED) != 0);
	}
      else if (mapping_anon_p)
	return (filterflags & COREFILTER_ANON_SHARED) != 0;
      else
	return (filterflags & COREFILTER_MAPPED_SHARED) != 0;
    }
}

/* Implement the "info proc" command.  */

static void
linux_info_proc (struct gdbarch *gdbarch, const char *args,
		 enum info_proc_what what)
{
  /* A long is used for pid instead of an int to avoid a loss of precision
     compiler warning from the output of strtoul.  */
  long pid;
  int cmdline_f = (what == IP_MINIMAL || what == IP_CMDLINE || what == IP_ALL);
  int cwd_f = (what == IP_MINIMAL || what == IP_CWD || what == IP_ALL);
  int exe_f = (what == IP_MINIMAL || what == IP_EXE || what == IP_ALL);
  int mappings_f = (what == IP_MAPPINGS || what == IP_ALL);
  int status_f = (what == IP_STATUS || what == IP_ALL);
  int stat_f = (what == IP_STAT || what == IP_ALL);
  char filename[100];
  char *data;
  int target_errno;

  if (args && isdigit (args[0]))
    {
      char *tem;

      pid = strtoul (args, &tem, 10);
      args = tem;
    }
  else
    {
      if (!target_has_execution)
	error (_("No current process: you must name one."));
      if (current_inferior ()->fake_pid_p)
	error (_("Can't determine the current process's PID: you must name one."));

      pid = current_inferior ()->pid;
    }

  args = skip_spaces (args);
  if (args && args[0])
    error (_("Too many parameters: %s"), args);

  printf_filtered (_("process %ld\n"), pid);
  if (cmdline_f)
    {
      xsnprintf (filename, sizeof filename, "/proc/%ld/cmdline", pid);
      gdb::unique_xmalloc_ptr<char> cmdline
	= target_fileio_read_stralloc (NULL, filename);
      if (cmdline)
	printf_filtered ("cmdline = '%s'\n", cmdline.get ());
      else
	warning (_("unable to open /proc file '%s'"), filename);
    }
  if (cwd_f)
    {
      xsnprintf (filename, sizeof filename, "/proc/%ld/cwd", pid);
      data = target_fileio_readlink (NULL, filename, &target_errno);
      if (data)
	{
	  struct cleanup *cleanup = make_cleanup (xfree, data);
          printf_filtered ("cwd = '%s'\n", data);
	  do_cleanups (cleanup);
	}
      else
	warning (_("unable to read link '%s'"), filename);
    }
  if (exe_f)
    {
      xsnprintf (filename, sizeof filename, "/proc/%ld/exe", pid);
      data = target_fileio_readlink (NULL, filename, &target_errno);
      if (data)
	{
	  struct cleanup *cleanup = make_cleanup (xfree, data);
          printf_filtered ("exe = '%s'\n", data);
	  do_cleanups (cleanup);
	}
      else
	warning (_("unable to read link '%s'"), filename);
    }
  if (mappings_f)
    {
      xsnprintf (filename, sizeof filename, "/proc/%ld/maps", pid);
      gdb::unique_xmalloc_ptr<char> map
	= target_fileio_read_stralloc (NULL, filename);
      if (map != NULL)
	{
	  char *line;

	  printf_filtered (_("Mapped address spaces:\n\n"));
	  if (gdbarch_addr_bit (gdbarch) == 32)
	    {
	      printf_filtered ("\t%10s %10s %10s %10s %s\n",
			   "Start Addr",
			   "  End Addr",
			   "      Size", "    Offset", "objfile");
            }
	  else
            {
	      printf_filtered ("  %18s %18s %10s %10s %s\n",
			   "Start Addr",
			   "  End Addr",
			   "      Size", "    Offset", "objfile");
	    }

	  for (line = strtok (map.get (), "\n");
	       line;
	       line = strtok (NULL, "\n"))
	    {
	      ULONGEST addr, endaddr, offset, inode;
	      const char *permissions, *device, *filename;
	      size_t permissions_len, device_len;

	      read_mapping (line, &addr, &endaddr,
			    &permissions, &permissions_len,
			    &offset, &device, &device_len,
			    &inode, &filename);

	      if (gdbarch_addr_bit (gdbarch) == 32)
	        {
	          printf_filtered ("\t%10s %10s %10s %10s %s\n",
				   paddress (gdbarch, addr),
				   paddress (gdbarch, endaddr),
				   hex_string (endaddr - addr),
				   hex_string (offset),
				   *filename? filename : "");
		}
	      else
	        {
	          printf_filtered ("  %18s %18s %10s %10s %s\n",
				   paddress (gdbarch, addr),
				   paddress (gdbarch, endaddr),
				   hex_string (endaddr - addr),
				   hex_string (offset),
				   *filename? filename : "");
	        }
	    }
	}
      else
	warning (_("unable to open /proc file '%s'"), filename);
    }
  if (status_f)
    {
      xsnprintf (filename, sizeof filename, "/proc/%ld/status", pid);
      gdb::unique_xmalloc_ptr<char> status
	= target_fileio_read_stralloc (NULL, filename);
      if (status)
	puts_filtered (status.get ());
      else
	warning (_("unable to open /proc file '%s'"), filename);
    }
  if (stat_f)
    {
      xsnprintf (filename, sizeof filename, "/proc/%ld/stat", pid);
      gdb::unique_xmalloc_ptr<char> statstr
	= target_fileio_read_stralloc (NULL, filename);
      if (statstr)
	{
	  const char *p = statstr.get ();

	  printf_filtered (_("Process: %s\n"),
			   pulongest (strtoulst (p, &p, 10)));

	  p = skip_spaces (p);
	  if (*p == '(')
	    {
	      /* ps command also relies on no trailing fields
		 ever contain ')'.  */
	      const char *ep = strrchr (p, ')');
	      if (ep != NULL)
		{
		  printf_filtered ("Exec file: %.*s\n",
				   (int) (ep - p - 1), p + 1);
		  p = ep + 1;
		}
	    }

	  p = skip_spaces (p);
	  if (*p)
	    printf_filtered (_("State: %c\n"), *p++);

	  if (*p)
	    printf_filtered (_("Parent process: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Process group: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Session id: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("TTY: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("TTY owner process group: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));

	  if (*p)
	    printf_filtered (_("Flags: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Minor faults (no memory page): %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Minor faults, children: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Major faults (memory page faults): %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Major faults, children: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("utime: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("stime: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("utime, children: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("stime, children: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("jiffies remaining in current "
			       "time slice: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("'nice' value: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("jiffies until next timeout: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("jiffies until next SIGALRM: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("start time (jiffies since "
			       "system boot): %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Virtual memory size: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Resident set size: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("rlim: %s\n"),
			     pulongest (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Start of text: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("End of text: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Start of stack: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
#if 0	/* Don't know how architecture-dependent the rest is...
	   Anyway the signal bitmap info is available from "status".  */
	  if (*p)
	    printf_filtered (_("Kernel stack pointer: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Kernel instr pointer: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Pending signals bitmap: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Blocked signals bitmap: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Ignored signals bitmap: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("Catched signals bitmap: %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
	  if (*p)
	    printf_filtered (_("wchan (system call): %s\n"),
			     hex_string (strtoulst (p, &p, 10)));
#endif
	}
      else
	warning (_("unable to open /proc file '%s'"), filename);
    }
}

/* Implement "info proc mappings" for a corefile.  */

static void
linux_core_info_proc_mappings (struct gdbarch *gdbarch, const char *args)
{
  asection *section;
  ULONGEST count, page_size;
  unsigned char *descdata, *filenames, *descend, *contents;
  size_t note_size;
  unsigned int addr_size_bits, addr_size;
  struct cleanup *cleanup;
  struct gdbarch *core_gdbarch = gdbarch_from_bfd (core_bfd);
  /* We assume this for reading 64-bit core files.  */
  gdb_static_assert (sizeof (ULONGEST) >= 8);

  section = bfd_get_section_by_name (core_bfd, ".note.linuxcore.file");
  if (section == NULL)
    {
      warning (_("unable to find mappings in core file"));
      return;
    }

  addr_size_bits = gdbarch_addr_bit (core_gdbarch);
  addr_size = addr_size_bits / 8;
  note_size = bfd_get_section_size (section);

  if (note_size < 2 * addr_size)
    error (_("malformed core note - too short for header"));

  contents = (unsigned char *) xmalloc (note_size);
  cleanup = make_cleanup (xfree, contents);
  if (!bfd_get_section_contents (core_bfd, section, contents, 0, note_size))
    error (_("could not get core note contents"));

  descdata = contents;
  descend = descdata + note_size;

  if (descdata[note_size - 1] != '\0')
    error (_("malformed note - does not end with \\0"));

  count = bfd_get (addr_size_bits, core_bfd, descdata);
  descdata += addr_size;

  page_size = bfd_get (addr_size_bits, core_bfd, descdata);
  descdata += addr_size;

  if (note_size < 2 * addr_size + count * 3 * addr_size)
    error (_("malformed note - too short for supplied file count"));

  printf_filtered (_("Mapped address spaces:\n\n"));
  if (gdbarch_addr_bit (gdbarch) == 32)
    {
      printf_filtered ("\t%10s %10s %10s %10s %s\n",
		       "Start Addr",
		       "  End Addr",
		       "      Size", "    Offset", "objfile");
    }
  else
    {
      printf_filtered ("  %18s %18s %10s %10s %s\n",
		       "Start Addr",
		       "  End Addr",
		       "      Size", "    Offset", "objfile");
    }

  filenames = descdata + count * 3 * addr_size;
  while (--count > 0)
    {
      ULONGEST start, end, file_ofs;

      if (filenames == descend)
	error (_("malformed note - filenames end too early"));

      start = bfd_get (addr_size_bits, core_bfd, descdata);
      descdata += addr_size;
      end = bfd_get (addr_size_bits, core_bfd, descdata);
      descdata += addr_size;
      file_ofs = bfd_get (addr_size_bits, core_bfd, descdata);
      descdata += addr_size;

      file_ofs *= page_size;

      if (gdbarch_addr_bit (gdbarch) == 32)
	printf_filtered ("\t%10s %10s %10s %10s %s\n",
			 paddress (gdbarch, start),
			 paddress (gdbarch, end),
			 hex_string (end - start),
			 hex_string (file_ofs),
			 filenames);
      else
	printf_filtered ("  %18s %18s %10s %10s %s\n",
			 paddress (gdbarch, start),
			 paddress (gdbarch, end),
			 hex_string (end - start),
			 hex_string (file_ofs),
			 filenames);

      filenames += 1 + strlen ((char *) filenames);
    }

  do_cleanups (cleanup);
}

/* Implement "info proc" for a corefile.  */

static void
linux_core_info_proc (struct gdbarch *gdbarch, const char *args,
		      enum info_proc_what what)
{
  int exe_f = (what == IP_MINIMAL || what == IP_EXE || what == IP_ALL);
  int mappings_f = (what == IP_MAPPINGS || what == IP_ALL);

  if (exe_f)
    {
      const char *exe;

      exe = bfd_core_file_failing_command (core_bfd);
      if (exe != NULL)
	printf_filtered ("exe = '%s'\n", exe);
      else
	warning (_("unable to find command name in core file"));
    }

  if (mappings_f)
    linux_core_info_proc_mappings (gdbarch, args);

  if (!exe_f && !mappings_f)
    error (_("unable to handle request"));
}

/* Read siginfo data from the core, if possible.  Returns -1 on
   failure.  Otherwise, returns the number of bytes read.  READBUF,
   OFFSET, and LEN are all as specified by the to_xfer_partial
   interface.  */

static LONGEST
linux_core_xfer_siginfo (struct gdbarch *gdbarch, gdb_byte *readbuf,
			 ULONGEST offset, ULONGEST len)
{
  thread_section_name section_name (".note.linuxcore.siginfo", inferior_ptid);
  asection *section = bfd_get_section_by_name (core_bfd, section_name.c_str ());
  if (section == NULL)
    return -1;

  if (!bfd_get_section_contents (core_bfd, section, readbuf, offset, len))
    return -1;

  return len;
}

typedef int linux_find_memory_region_ftype (ULONGEST vaddr, ULONGEST size,
					    ULONGEST offset, ULONGEST inode,
					    int read, int write,
					    int exec, int modified,
					    const char *filename,
					    void *data);

/* List memory regions in the inferior for a corefile.  */

static int
linux_find_memory_regions_full (struct gdbarch *gdbarch,
				linux_find_memory_region_ftype *func,
				void *obfd)
{
  char mapsfilename[100];
  char coredumpfilter_name[100];
  pid_t pid;
  /* Default dump behavior of coredump_filter (0x33), according to
     Documentation/filesystems/proc.txt from the Linux kernel
     tree.  */
  filter_flags filterflags = (COREFILTER_ANON_PRIVATE
			      | COREFILTER_ANON_SHARED
			      | COREFILTER_ELF_HEADERS
			      | COREFILTER_HUGETLB_PRIVATE);

  /* We need to know the real target PID to access /proc.  */
  if (current_inferior ()->fake_pid_p)
    return 1;

  pid = current_inferior ()->pid;

  if (use_coredump_filter)
    {
      xsnprintf (coredumpfilter_name, sizeof (coredumpfilter_name),
		 "/proc/%d/coredump_filter", pid);
      gdb::unique_xmalloc_ptr<char> coredumpfilterdata
	= target_fileio_read_stralloc (NULL, coredumpfilter_name);
      if (coredumpfilterdata != NULL)
	{
	  unsigned int flags;

	  sscanf (coredumpfilterdata.get (), "%x", &flags);
	  filterflags = (enum filter_flag) flags;
	}
    }

  xsnprintf (mapsfilename, sizeof mapsfilename, "/proc/%d/smaps", pid);
  gdb::unique_xmalloc_ptr<char> data
    = target_fileio_read_stralloc (NULL, mapsfilename);
  if (data == NULL)
    {
      /* Older Linux kernels did not support /proc/PID/smaps.  */
      xsnprintf (mapsfilename, sizeof mapsfilename, "/proc/%d/maps", pid);
      data = target_fileio_read_stralloc (NULL, mapsfilename);
    }

  if (data != NULL)
    {
      char *line, *t;

      line = strtok_r (data.get (), "\n", &t);
      while (line != NULL)
	{
	  ULONGEST addr, endaddr, offset, inode;
	  const char *permissions, *device, *filename;
	  struct smaps_vmflags v;
	  size_t permissions_len, device_len;
	  int read, write, exec, priv;
	  int has_anonymous = 0;
	  int should_dump_p = 0;
	  int mapping_anon_p;
	  int mapping_file_p;

	  memset (&v, 0, sizeof (v));
	  read_mapping (line, &addr, &endaddr, &permissions, &permissions_len,
			&offset, &device, &device_len, &inode, &filename);
	  mapping_anon_p = mapping_is_anonymous_p (filename);
	  /* If the mapping is not anonymous, then we can consider it
	     to be file-backed.  These two states (anonymous or
	     file-backed) seem to be exclusive, but they can actually
	     coexist.  For example, if a file-backed mapping has
	     "Anonymous:" pages (see more below), then the Linux
	     kernel will dump this mapping when the user specified
	     that she only wants anonymous mappings in the corefile
	     (*even* when she explicitly disabled the dumping of
	     file-backed mappings).  */
	  mapping_file_p = !mapping_anon_p;

	  /* Decode permissions.  */
	  read = (memchr (permissions, 'r', permissions_len) != 0);
	  write = (memchr (permissions, 'w', permissions_len) != 0);
	  exec = (memchr (permissions, 'x', permissions_len) != 0);
	  /* 'private' here actually means VM_MAYSHARE, and not
	     VM_SHARED.  In order to know if a mapping is really
	     private or not, we must check the flag "sh" in the
	     VmFlags field.  This is done by decode_vmflags.  However,
	     if we are using a Linux kernel released before the commit
	     834f82e2aa9a8ede94b17b656329f850c1471514 (3.10), we will
	     not have the VmFlags there.  In this case, there is
	     really no way to know if we are dealing with VM_SHARED,
	     so we just assume that VM_MAYSHARE is enough.  */
	  priv = memchr (permissions, 'p', permissions_len) != 0;

	  /* Try to detect if region should be dumped by parsing smaps
	     counters.  */
	  for (line = strtok_r (NULL, "\n", &t);
	       line != NULL && line[0] >= 'A' && line[0] <= 'Z';
	       line = strtok_r (NULL, "\n", &t))
	    {
	      char keyword[64 + 1];

	      if (sscanf (line, "%64s", keyword) != 1)
		{
		  warning (_("Error parsing {s,}maps file '%s'"), mapsfilename);
		  break;
		}

	      if (strcmp (keyword, "Anonymous:") == 0)
		{
		  /* Older Linux kernels did not support the
		     "Anonymous:" counter.  Check it here.  */
		  has_anonymous = 1;
		}
	      else if (strcmp (keyword, "VmFlags:") == 0)
		decode_vmflags (line, &v);

	      if (strcmp (keyword, "AnonHugePages:") == 0
		  || strcmp (keyword, "Anonymous:") == 0)
		{
		  unsigned long number;

		  if (sscanf (line, "%*s%lu", &number) != 1)
		    {
		      warning (_("Error parsing {s,}maps file '%s' number"),
			       mapsfilename);
		      break;
		    }
		  if (number > 0)
		    {
		      /* Even if we are dealing with a file-backed
			 mapping, if it contains anonymous pages we
			 consider it to be *also* an anonymous
			 mapping, because this is what the Linux
			 kernel does:

			 // Dump segments that have been written to.
			 if (vma->anon_vma && FILTER(ANON_PRIVATE))
			 	goto whole;

			 Note that if the mapping is already marked as
			 file-backed (i.e., mapping_file_p is
			 non-zero), then this is a special case, and
			 this mapping will be dumped either when the
			 user wants to dump file-backed *or* anonymous
			 mappings.  */
		      mapping_anon_p = 1;
		    }
		}
	    }

	  if (has_anonymous)
	    should_dump_p = dump_mapping_p (filterflags, &v, priv,
					    mapping_anon_p, mapping_file_p,
					    filename);
	  else
	    {
	      /* Older Linux kernels did not support the "Anonymous:" counter.
		 If it is missing, we can't be sure - dump all the pages.  */
	      should_dump_p = 1;
	    }

	  /* Invoke the callback function to create the corefile segment.  */
	  if (should_dump_p)
	    func (addr, endaddr - addr, offset, inode,
		  read, write, exec, 1, /* MODIFIED is true because we
					   want to dump the mapping.  */
		  filename, obfd);
	}

      return 0;
    }

  return 1;
}

/* A structure for passing information through
   linux_find_memory_regions_full.  */

struct linux_find_memory_regions_data
{
  /* The original callback.  */

  find_memory_region_ftype func;

  /* The original datum.  */

  void *obfd;
};

/* A callback for linux_find_memory_regions that converts between the
   "full"-style callback and find_memory_region_ftype.  */

static int
linux_find_memory_regions_thunk (ULONGEST vaddr, ULONGEST size,
				 ULONGEST offset, ULONGEST inode,
				 int read, int write, int exec, int modified,
				 const char *filename, void *arg)
{
  struct linux_find_memory_regions_data *data
    = (struct linux_find_memory_regions_data *) arg;

  return data->func (vaddr, size, read, write, exec, modified, data->obfd);
}

/* A variant of linux_find_memory_regions_full that is suitable as the
   gdbarch find_memory_regions method.  */

static int
linux_find_memory_regions (struct gdbarch *gdbarch,
			   find_memory_region_ftype func, void *obfd)
{
  struct linux_find_memory_regions_data data;

  data.func = func;
  data.obfd = obfd;

  return linux_find_memory_regions_full (gdbarch,
					 linux_find_memory_regions_thunk,
					 &data);
}

/* Determine which signal stopped execution.  */

static int
find_signalled_thread (struct thread_info *info, void *data)
{
  if (info->suspend.stop_signal != GDB_SIGNAL_0
      && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid))
    return 1;

  return 0;
}

/* Generate corefile notes for SPU contexts.  */

static char *
linux_spu_make_corefile_notes (bfd *obfd, char *note_data, int *note_size)
{
  static const char *spu_files[] =
    {
      "object-id",
      "mem",
      "regs",
      "fpcr",
      "lslr",
      "decr",
      "decr_status",
      "signal1",
      "signal1_type",
      "signal2",
      "signal2_type",
      "event_mask",
      "event_status",
      "mbox_info",
      "ibox_info",
      "wbox_info",
      "dma_info",
      "proxydma_info",
   };

  enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
  gdb_byte *spu_ids;
  LONGEST i, j, size;

  /* Determine list of SPU ids.  */
  size = target_read_alloc (&current_target, TARGET_OBJECT_SPU,
			    NULL, &spu_ids);

  /* Generate corefile notes for each SPU file.  */
  for (i = 0; i < size; i += 4)
    {
      int fd = extract_unsigned_integer (spu_ids + i, 4, byte_order);

      for (j = 0; j < sizeof (spu_files) / sizeof (spu_files[0]); j++)
	{
	  char annex[32], note_name[32];
	  gdb_byte *spu_data;
	  LONGEST spu_len;

	  xsnprintf (annex, sizeof annex, "%d/%s", fd, spu_files[j]);
	  spu_len = target_read_alloc (&current_target, TARGET_OBJECT_SPU,
				       annex, &spu_data);
	  if (spu_len > 0)
	    {
	      xsnprintf (note_name, sizeof note_name, "SPU/%s", annex);
	      note_data = elfcore_write_note (obfd, note_data, note_size,
					      note_name, NT_SPU,
					      spu_data, spu_len);
	      xfree (spu_data);

	      if (!note_data)
		{
		  xfree (spu_ids);
		  return NULL;
		}
	    }
	}
    }

  if (size > 0)
    xfree (spu_ids);

  return note_data;
}

/* This is used to pass information from
   linux_make_mappings_corefile_notes through
   linux_find_memory_regions_full.  */

struct linux_make_mappings_data
{
  /* Number of files mapped.  */
  ULONGEST file_count;

  /* The obstack for the main part of the data.  */
  struct obstack *data_obstack;

  /* The filename obstack.  */
  struct obstack *filename_obstack;

  /* The architecture's "long" type.  */
  struct type *long_type;
};

static linux_find_memory_region_ftype linux_make_mappings_callback;

/* A callback for linux_find_memory_regions_full that updates the
   mappings data for linux_make_mappings_corefile_notes.  */

static int
linux_make_mappings_callback (ULONGEST vaddr, ULONGEST size,
			      ULONGEST offset, ULONGEST inode,
			      int read, int write, int exec, int modified,
			      const char *filename, void *data)
{
  struct linux_make_mappings_data *map_data
    = (struct linux_make_mappings_data *) data;
  gdb_byte buf[sizeof (ULONGEST)];

  if (*filename == '\0' || inode == 0)
    return 0;

  ++map_data->file_count;

  pack_long (buf, map_data->long_type, vaddr);
  obstack_grow (map_data->data_obstack, buf, TYPE_LENGTH (map_data->long_type));
  pack_long (buf, map_data->long_type, vaddr + size);
  obstack_grow (map_data->data_obstack, buf, TYPE_LENGTH (map_data->long_type));
  pack_long (buf, map_data->long_type, offset);
  obstack_grow (map_data->data_obstack, buf, TYPE_LENGTH (map_data->long_type));

  obstack_grow_str0 (map_data->filename_obstack, filename);

  return 0;
}

/* Write the file mapping data to the core file, if possible.  OBFD is
   the output BFD.  NOTE_DATA is the current note data, and NOTE_SIZE
   is a pointer to the note size.  Returns the new NOTE_DATA and
   updates NOTE_SIZE.  */

static char *
linux_make_mappings_corefile_notes (struct gdbarch *gdbarch, bfd *obfd,
				    char *note_data, int *note_size)
{
  struct cleanup *cleanup;
  struct linux_make_mappings_data mapping_data;
  struct type *long_type
    = arch_integer_type (gdbarch, gdbarch_long_bit (gdbarch), 0, "long");
  gdb_byte buf[sizeof (ULONGEST)];

  auto_obstack data_obstack, filename_obstack;

  mapping_data.file_count = 0;
  mapping_data.data_obstack = &data_obstack;
  mapping_data.filename_obstack = &filename_obstack;
  mapping_data.long_type = long_type;

  /* Reserve space for the count.  */
  obstack_blank (&data_obstack, TYPE_LENGTH (long_type));
  /* We always write the page size as 1 since we have no good way to
     determine the correct value.  */
  pack_long (buf, long_type, 1);
  obstack_grow (&data_obstack, buf, TYPE_LENGTH (long_type));

  linux_find_memory_regions_full (gdbarch, linux_make_mappings_callback,
				  &mapping_data);

  if (mapping_data.file_count != 0)
    {
      /* Write the count to the obstack.  */
      pack_long ((gdb_byte *) obstack_base (&data_obstack),
		 long_type, mapping_data.file_count);

      /* Copy the filenames to the data obstack.  */
      obstack_grow (&data_obstack, obstack_base (&filename_obstack),
		    obstack_object_size (&filename_obstack));

      note_data = elfcore_write_note (obfd, note_data, note_size,
				      "CORE", NT_FILE,
				      obstack_base (&data_obstack),
				      obstack_object_size (&data_obstack));
    }

  return note_data;
}

/* Structure for passing information from
   linux_collect_thread_registers via an iterator to
   linux_collect_regset_section_cb. */

struct linux_collect_regset_section_cb_data
{
  struct gdbarch *gdbarch;
  const struct regcache *regcache;
  bfd *obfd;
  char *note_data;
  int *note_size;
  unsigned long lwp;
  enum gdb_signal stop_signal;
  int abort_iteration;
};

/* Callback for iterate_over_regset_sections that records a single
   regset in the corefile note section.  */

static void
linux_collect_regset_section_cb (const char *sect_name, int size,
				 const struct regset *regset,
				 const char *human_name, void *cb_data)
{
  char *buf;
  struct linux_collect_regset_section_cb_data *data
    = (struct linux_collect_regset_section_cb_data *) cb_data;

  if (data->abort_iteration)
    return;

  gdb_assert (regset && regset->collect_regset);

  buf = (char *) xmalloc (size);
  regset->collect_regset (regset, data->regcache, -1, buf, size);

  /* PRSTATUS still needs to be treated specially.  */
  if (strcmp (sect_name, ".reg") == 0)
    data->note_data = (char *) elfcore_write_prstatus
      (data->obfd, data->note_data, data->note_size, data->lwp,
       gdb_signal_to_host (data->stop_signal), buf);
  else
    data->note_data = (char *) elfcore_write_register_note
      (data->obfd, data->note_data, data->note_size,
       sect_name, buf, size);
  xfree (buf);

  if (data->note_data == NULL)
    data->abort_iteration = 1;
}

/* Records the thread's register state for the corefile note
   section.  */

static char *
linux_collect_thread_registers (const struct regcache *regcache,
				ptid_t ptid, bfd *obfd,
				char *note_data, int *note_size,
				enum gdb_signal stop_signal)
{
  struct gdbarch *gdbarch = get_regcache_arch (regcache);
  struct linux_collect_regset_section_cb_data data;

  data.gdbarch = gdbarch;
  data.regcache = regcache;
  data.obfd = obfd;
  data.note_data = note_data;
  data.note_size = note_size;
  data.stop_signal = stop_signal;
  data.abort_iteration = 0;

  /* For remote targets the LWP may not be available, so use the TID.  */
  data.lwp = ptid_get_lwp (ptid);
  if (!data.lwp)
    data.lwp = ptid_get_tid (ptid);

  gdbarch_iterate_over_regset_sections (gdbarch,
					linux_collect_regset_section_cb,
					&data, regcache);
  return data.note_data;
}

/* Fetch the siginfo data for the specified thread, if it exists.  If
   there is no data, or we could not read it, return NULL.  Otherwise,
   return a newly malloc'd buffer holding the data and fill in *SIZE
   with the size of the data.  The caller is responsible for freeing
   the data.  */

static gdb_byte *
linux_get_siginfo_data (thread_info *thread, struct gdbarch *gdbarch,
			LONGEST *size)
{
  struct type *siginfo_type;
  gdb_byte *buf;
  LONGEST bytes_read;
  struct cleanup *cleanups;

  if (!gdbarch_get_siginfo_type_p (gdbarch))
    return NULL;
  
  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
  inferior_ptid = thread->ptid;

  siginfo_type = gdbarch_get_siginfo_type (gdbarch);

  buf = (gdb_byte *) xmalloc (TYPE_LENGTH (siginfo_type));
  cleanups = make_cleanup (xfree, buf);

  bytes_read = target_read (&current_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
			    buf, 0, TYPE_LENGTH (siginfo_type));
  if (bytes_read == TYPE_LENGTH (siginfo_type))
    {
      discard_cleanups (cleanups);
      *size = bytes_read;
    }
  else
    {
      do_cleanups (cleanups);
      buf = NULL;
    }

  return buf;
}

struct linux_corefile_thread_data
{
  struct gdbarch *gdbarch;
  bfd *obfd;
  char *note_data;
  int *note_size;
  enum gdb_signal stop_signal;
};

/* Records the thread's register state for the corefile note
   section.  */

static void
linux_corefile_thread (struct thread_info *info,
		       struct linux_corefile_thread_data *args)
{
  struct cleanup *old_chain;
  struct regcache *regcache;
  gdb_byte *siginfo_data;
  LONGEST siginfo_size = 0;

  regcache = get_thread_arch_regcache (info->ptid, args->gdbarch);

  target_fetch_registers (regcache, -1);
  siginfo_data = linux_get_siginfo_data (info, args->gdbarch, &siginfo_size);

  old_chain = make_cleanup (xfree, siginfo_data);

  args->note_data = linux_collect_thread_registers
    (regcache, info->ptid, args->obfd, args->note_data,
     args->note_size, args->stop_signal);

  /* Don't return anything if we got no register information above,
     such a core file is useless.  */
  if (args->note_data != NULL)
    if (siginfo_data != NULL)
      args->note_data = elfcore_write_note (args->obfd,
					    args->note_data,
					    args->note_size,
					    "CORE", NT_SIGINFO,
					    siginfo_data, siginfo_size);

  do_cleanups (old_chain);
}

/* Fill the PRPSINFO structure with information about the process being
   debugged.  Returns 1 in case of success, 0 for failures.  Please note that
   even if the structure cannot be entirely filled (e.g., GDB was unable to
   gather information about the process UID/GID), this function will still
   return 1 since some information was already recorded.  It will only return
   0 iff nothing can be gathered.  */

static int
linux_fill_prpsinfo (struct elf_internal_linux_prpsinfo *p)
{
  /* The filename which we will use to obtain some info about the process.
     We will basically use this to store the `/proc/PID/FILENAME' file.  */
  char filename[100];
  /* The basename of the executable.  */
  const char *basename;
  char *infargs;
  /* Temporary buffer.  */
  char *tmpstr;
  /* The valid states of a process, according to the Linux kernel.  */
  const char valid_states[] = "RSDTZW";
  /* The program state.  */
  const char *prog_state;
  /* The state of the process.  */
  char pr_sname;
  /* The PID of the program which generated the corefile.  */
  pid_t pid;
  /* Process flags.  */
  unsigned int pr_flag;
  /* Process nice value.  */
  long pr_nice;
  /* The number of fields read by `sscanf'.  */
  int n_fields = 0;

  gdb_assert (p != NULL);

  /* Obtaining PID and filename.  */
  pid = ptid_get_pid (inferior_ptid);
  xsnprintf (filename, sizeof (filename), "/proc/%d/cmdline", (int) pid);
  /* The full name of the program which generated the corefile.  */
  gdb::unique_xmalloc_ptr<char> fname
    = target_fileio_read_stralloc (NULL, filename);

  if (fname == NULL || fname.get ()[0] == '\0')
    {
      /* No program name was read, so we won't be able to retrieve more
	 information about the process.  */
      return 0;
    }

  memset (p, 0, sizeof (*p));

  /* Defining the PID.  */
  p->pr_pid = pid;

  /* Copying the program name.  Only the basename matters.  */
  basename = lbasename (fname.get ());
  strncpy (p->pr_fname, basename, sizeof (p->pr_fname));
  p->pr_fname[sizeof (p->pr_fname) - 1] = '\0';

  infargs = get_inferior_args ();

  /* The arguments of the program.  */
  std::string psargs = fname.get ();
  if (infargs != NULL)
    psargs = psargs + " " + infargs;

  strncpy (p->pr_psargs, psargs.c_str (), sizeof (p->pr_psargs));
  p->pr_psargs[sizeof (p->pr_psargs) - 1] = '\0';

  xsnprintf (filename, sizeof (filename), "/proc/%d/stat", (int) pid);
  /* The contents of `/proc/PID/stat'.  */
  gdb::unique_xmalloc_ptr<char> proc_stat_contents
    = target_fileio_read_stralloc (NULL, filename);
  char *proc_stat = proc_stat_contents.get ();

  if (proc_stat == NULL || *proc_stat == '\0')
    {
      /* Despite being unable to read more information about the
	 process, we return 1 here because at least we have its
	 command line, PID and arguments.  */
      return 1;
    }

  /* Ok, we have the stats.  It's time to do a little parsing of the
     contents of the buffer, so that we end up reading what we want.

     The following parsing mechanism is strongly based on the
     information generated by the `fs/proc/array.c' file, present in
     the Linux kernel tree.  More details about how the information is
     displayed can be obtained by seeing the manpage of proc(5),
     specifically under the entry of `/proc/[pid]/stat'.  */

  /* Getting rid of the PID, since we already have it.  */
  while (isdigit (*proc_stat))
    ++proc_stat;

  proc_stat = skip_spaces (proc_stat);

  /* ps command also relies on no trailing fields ever contain ')'.  */
  proc_stat = strrchr (proc_stat, ')');
  if (proc_stat == NULL)
    return 1;
  proc_stat++;

  proc_stat = skip_spaces (proc_stat);

  n_fields = sscanf (proc_stat,
		     "%c"		/* Process state.  */
		     "%d%d%d"		/* Parent PID, group ID, session ID.  */
		     "%*d%*d"		/* tty_nr, tpgid (not used).  */
		     "%u"		/* Flags.  */
		     "%*s%*s%*s%*s"	/* minflt, cminflt, majflt,
					   cmajflt (not used).  */
		     "%*s%*s%*s%*s"	/* utime, stime, cutime,
					   cstime (not used).  */
		     "%*s"		/* Priority (not used).  */
		     "%ld",		/* Nice.  */
		     &pr_sname,
		     &p->pr_ppid, &p->pr_pgrp, &p->pr_sid,
		     &pr_flag,
		     &pr_nice);

  if (n_fields != 6)
    {
      /* Again, we couldn't read the complementary information about
	 the process state.  However, we already have minimal
	 information, so we just return 1 here.  */
      return 1;
    }

  /* Filling the structure fields.  */
  prog_state = strchr (valid_states, pr_sname);
  if (prog_state != NULL)
    p->pr_state = prog_state - valid_states;
  else
    {
      /* Zero means "Running".  */
      p->pr_state = 0;
    }

  p->pr_sname = p->pr_state > 5 ? '.' : pr_sname;
  p->pr_zomb = p->pr_sname == 'Z';
  p->pr_nice = pr_nice;
  p->pr_flag = pr_flag;

  /* Finally, obtaining the UID and GID.  For that, we read and parse the
     contents of the `/proc/PID/status' file.  */
  xsnprintf (filename, sizeof (filename), "/proc/%d/status", (int) pid);
  /* The contents of `/proc/PID/status'.  */
  gdb::unique_xmalloc_ptr<char> proc_status_contents
    = target_fileio_read_stralloc (NULL, filename);
  char *proc_status = proc_status_contents.get ();

  if (proc_status == NULL || *proc_status == '\0')
    {
      /* Returning 1 since we already have a bunch of information.  */
      return 1;
    }

  /* Extracting the UID.  */
  tmpstr = strstr (proc_status, "Uid:");
  if (tmpstr != NULL)
    {
      /* Advancing the pointer to the beginning of the UID.  */
      tmpstr += sizeof ("Uid:");
      while (*tmpstr != '\0' && !isdigit (*tmpstr))
	++tmpstr;

      if (isdigit (*tmpstr))
	p->pr_uid = strtol (tmpstr, &tmpstr, 10);
    }

  /* Extracting the GID.  */
  tmpstr = strstr (proc_status, "Gid:");
  if (tmpstr != NULL)
    {
      /* Advancing the pointer to the beginning of the GID.  */
      tmpstr += sizeof ("Gid:");
      while (*tmpstr != '\0' && !isdigit (*tmpstr))
	++tmpstr;

      if (isdigit (*tmpstr))
	p->pr_gid = strtol (tmpstr, &tmpstr, 10);
    }

  return 1;
}

/* Build the note section for a corefile, and return it in a malloc
   buffer.  */

static char *
linux_make_corefile_notes (struct gdbarch *gdbarch, bfd *obfd, int *note_size)
{
  struct linux_corefile_thread_data thread_args;
  struct elf_internal_linux_prpsinfo prpsinfo;
  char *note_data = NULL;
  gdb_byte *auxv;
  int auxv_len;
  struct thread_info *curr_thr, *signalled_thr, *thr;

  if (! gdbarch_iterate_over_regset_sections_p (gdbarch))
    return NULL;

  if (linux_fill_prpsinfo (&prpsinfo))
    {
      if (gdbarch_ptr_bit (gdbarch) == 64)
	note_data = elfcore_write_linux_prpsinfo64 (obfd,
						    note_data, note_size,
						    &prpsinfo);
      else
	note_data = elfcore_write_linux_prpsinfo32 (obfd,
						    note_data, note_size,
						    &prpsinfo);
    }

  /* Thread register information.  */
  TRY
    {
      update_thread_list ();
    }
  CATCH (e, RETURN_MASK_ERROR)
    {
      exception_print (gdb_stderr, e);
    }
  END_CATCH

  /* Like the kernel, prefer dumping the signalled thread first.
     "First thread" is what tools use to infer the signalled thread.
     In case there's more than one signalled thread, prefer the
     current thread, if it is signalled.  */
  curr_thr = inferior_thread ();
  if (curr_thr->suspend.stop_signal != GDB_SIGNAL_0)
    signalled_thr = curr_thr;
  else
    {
      signalled_thr = iterate_over_threads (find_signalled_thread, NULL);
      if (signalled_thr == NULL)
	signalled_thr = curr_thr;
    }

  thread_args.gdbarch = gdbarch;
  thread_args.obfd = obfd;
  thread_args.note_data = note_data;
  thread_args.note_size = note_size;
  thread_args.stop_signal = signalled_thr->suspend.stop_signal;

  linux_corefile_thread (signalled_thr, &thread_args);
  ALL_NON_EXITED_THREADS (thr)
    {
      if (thr == signalled_thr)
	continue;
      if (ptid_get_pid (thr->ptid) != ptid_get_pid (inferior_ptid))
	continue;

      linux_corefile_thread (thr, &thread_args);
    }

  note_data = thread_args.note_data;
  if (!note_data)
    return NULL;

  /* Auxillary vector.  */
  auxv_len = target_read_alloc (&current_target, TARGET_OBJECT_AUXV,
				NULL, &auxv);
  if (auxv_len > 0)
    {
      note_data = elfcore_write_note (obfd, note_data, note_size,
				      "CORE", NT_AUXV, auxv, auxv_len);
      xfree (auxv);

      if (!note_data)
	return NULL;
    }

  /* SPU information.  */
  note_data = linux_spu_make_corefile_notes (obfd, note_data, note_size);
  if (!note_data)
    return NULL;

  /* File mappings.  */
  note_data = linux_make_mappings_corefile_notes (gdbarch, obfd,
						  note_data, note_size);

  return note_data;
}

/* Implementation of `gdbarch_gdb_signal_from_target', as defined in
   gdbarch.h.  This function is not static because it is exported to
   other -tdep files.  */

enum gdb_signal
linux_gdb_signal_from_target (struct gdbarch *gdbarch, int signal)
{
  switch (signal)
    {
    case 0:
      return GDB_SIGNAL_0;

    case LINUX_SIGHUP:
      return GDB_SIGNAL_HUP;

    case LINUX_SIGINT:
      return GDB_SIGNAL_INT;

    case LINUX_SIGQUIT:
      return GDB_SIGNAL_QUIT;

    case LINUX_SIGILL:
      return GDB_SIGNAL_ILL;

    case LINUX_SIGTRAP:
      return GDB_SIGNAL_TRAP;

    case LINUX_SIGABRT:
      return GDB_SIGNAL_ABRT;

    case LINUX_SIGBUS:
      return GDB_SIGNAL_BUS;

    case LINUX_SIGFPE:
      return GDB_SIGNAL_FPE;

    case LINUX_SIGKILL:
      return GDB_SIGNAL_KILL;

    case LINUX_SIGUSR1:
      return GDB_SIGNAL_USR1;

    case LINUX_SIGSEGV:
      return GDB_SIGNAL_SEGV;

    case LINUX_SIGUSR2:
      return GDB_SIGNAL_USR2;

    case LINUX_SIGPIPE:
      return GDB_SIGNAL_PIPE;

    case LINUX_SIGALRM:
      return GDB_SIGNAL_ALRM;

    case LINUX_SIGTERM:
      return GDB_SIGNAL_TERM;

    case LINUX_SIGCHLD:
      return GDB_SIGNAL_CHLD;

    case LINUX_SIGCONT:
      return GDB_SIGNAL_CONT;

    case LINUX_SIGSTOP:
      return GDB_SIGNAL_STOP;

    case LINUX_SIGTSTP:
      return GDB_SIGNAL_TSTP;

    case LINUX_SIGTTIN:
      return GDB_SIGNAL_TTIN;

    case LINUX_SIGTTOU:
      return GDB_SIGNAL_TTOU;

    case LINUX_SIGURG:
      return GDB_SIGNAL_URG;

    case LINUX_SIGXCPU:
      return GDB_SIGNAL_XCPU;

    case LINUX_SIGXFSZ:
      return GDB_SIGNAL_XFSZ;

    case LINUX_SIGVTALRM:
      return GDB_SIGNAL_VTALRM;

    case LINUX_SIGPROF:
      return GDB_SIGNAL_PROF;

    case LINUX_SIGWINCH:
      return GDB_SIGNAL_WINCH;

    /* No way to differentiate between SIGIO and SIGPOLL.
       Therefore, we just handle the first one.  */
    case LINUX_SIGIO:
      return GDB_SIGNAL_IO;

    case LINUX_SIGPWR:
      return GDB_SIGNAL_PWR;

    case LINUX_SIGSYS:
      return GDB_SIGNAL_SYS;

    /* SIGRTMIN and SIGRTMAX are not continuous in <gdb/signals.def>,
       therefore we have to handle them here.  */
    case LINUX_SIGRTMIN:
      return GDB_SIGNAL_REALTIME_32;

    case LINUX_SIGRTMAX:
      return GDB_SIGNAL_REALTIME_64;
    }

  if (signal >= LINUX_SIGRTMIN + 1 && signal <= LINUX_SIGRTMAX - 1)
    {
      int offset = signal - LINUX_SIGRTMIN + 1;

      return (enum gdb_signal) ((int) GDB_SIGNAL_REALTIME_33 + offset);
    }

  return GDB_SIGNAL_UNKNOWN;
}

/* Implementation of `gdbarch_gdb_signal_to_target', as defined in
   gdbarch.h.  This function is not static because it is exported to
   other -tdep files.  */

int
linux_gdb_signal_to_target (struct gdbarch *gdbarch,
			    enum gdb_signal signal)
{
  switch (signal)
    {
    case GDB_SIGNAL_0:
      return 0;

    case GDB_SIGNAL_HUP:
      return LINUX_SIGHUP;

    case GDB_SIGNAL_INT:
      return LINUX_SIGINT;

    case GDB_SIGNAL_QUIT:
      return LINUX_SIGQUIT;

    case GDB_SIGNAL_ILL:
      return LINUX_SIGILL;

    case GDB_SIGNAL_TRAP:
      return LINUX_SIGTRAP;

    case GDB_SIGNAL_ABRT:
      return LINUX_SIGABRT;

    case GDB_SIGNAL_FPE:
      return LINUX_SIGFPE;

    case GDB_SIGNAL_KILL:
      return LINUX_SIGKILL;

    case GDB_SIGNAL_BUS:
      return LINUX_SIGBUS;

    case GDB_SIGNAL_SEGV:
      return LINUX_SIGSEGV;

    case GDB_SIGNAL_SYS:
      return LINUX_SIGSYS;

    case GDB_SIGNAL_PIPE:
      return LINUX_SIGPIPE;

    case GDB_SIGNAL_ALRM:
      return LINUX_SIGALRM;

    case GDB_SIGNAL_TERM:
      return LINUX_SIGTERM;

    case GDB_SIGNAL_URG:
      return LINUX_SIGURG;

    case GDB_SIGNAL_STOP:
      return LINUX_SIGSTOP;

    case GDB_SIGNAL_TSTP:
      return LINUX_SIGTSTP;

    case GDB_SIGNAL_CONT:
      return LINUX_SIGCONT;

    case GDB_SIGNAL_CHLD:
      return LINUX_SIGCHLD;

    case GDB_SIGNAL_TTIN:
      return LINUX_SIGTTIN;

    case GDB_SIGNAL_TTOU:
      return LINUX_SIGTTOU;

    case GDB_SIGNAL_IO:
      return LINUX_SIGIO;

    case GDB_SIGNAL_XCPU:
      return LINUX_SIGXCPU;

    case GDB_SIGNAL_XFSZ:
      return LINUX_SIGXFSZ;

    case GDB_SIGNAL_VTALRM:
      return LINUX_SIGVTALRM;

    case GDB_SIGNAL_PROF:
      return LINUX_SIGPROF;

    case GDB_SIGNAL_WINCH:
      return LINUX_SIGWINCH;

    case GDB_SIGNAL_USR1:
      return LINUX_SIGUSR1;

    case GDB_SIGNAL_USR2:
      return LINUX_SIGUSR2;

    case GDB_SIGNAL_PWR:
      return LINUX_SIGPWR;

    case GDB_SIGNAL_POLL:
      return LINUX_SIGPOLL;

    /* GDB_SIGNAL_REALTIME_32 is not continuous in <gdb/signals.def>,
       therefore we have to handle it here.  */
    case GDB_SIGNAL_REALTIME_32:
      return LINUX_SIGRTMIN;

    /* Same comment applies to _64.  */
    case GDB_SIGNAL_REALTIME_64:
      return LINUX_SIGRTMAX;
    }

  /* GDB_SIGNAL_REALTIME_33 to _64 are continuous.  */
  if (signal >= GDB_SIGNAL_REALTIME_33
      && signal <= GDB_SIGNAL_REALTIME_63)
    {
      int offset = signal - GDB_SIGNAL_REALTIME_33;

      return LINUX_SIGRTMIN + 1 + offset;
    }

  return -1;
}

/* Helper for linux_vsyscall_range that does the real work of finding
   the vsyscall's address range.  */

static int
linux_vsyscall_range_raw (struct gdbarch *gdbarch, struct mem_range *range)
{
  char filename[100];
  long pid;

  if (target_auxv_search (&current_target, AT_SYSINFO_EHDR, &range->start) <= 0)
    return 0;

  /* It doesn't make sense to access the host's /proc when debugging a
     core file.  Instead, look for the PT_LOAD segment that matches
     the vDSO.  */
  if (!target_has_execution)
    {
      Elf_Internal_Phdr *phdrs;
      long phdrs_size;
      int num_phdrs, i;

      phdrs_size = bfd_get_elf_phdr_upper_bound (core_bfd);
      if (phdrs_size == -1)
	return 0;

      phdrs = (Elf_Internal_Phdr *) alloca (phdrs_size);
      num_phdrs = bfd_get_elf_phdrs (core_bfd, phdrs);
      if (num_phdrs == -1)
	return 0;

      for (i = 0; i < num_phdrs; i++)
	if (phdrs[i].p_type == PT_LOAD
	    && phdrs[i].p_vaddr == range->start)
	  {
	    range->length = phdrs[i].p_memsz;
	    return 1;
	  }

      return 0;
    }

  /* We need to know the real target PID to access /proc.  */
  if (current_inferior ()->fake_pid_p)
    return 0;

  pid = current_inferior ()->pid;

  /* Note that reading /proc/PID/task/PID/maps (1) is much faster than
     reading /proc/PID/maps (2).  The later identifies thread stacks
     in the output, which requires scanning every thread in the thread
     group to check whether a VMA is actually a thread's stack.  With
     Linux 4.4 on an Intel i7-4810MQ @ 2.80GHz, with an inferior with
     a few thousand threads, (1) takes a few miliseconds, while (2)
     takes several seconds.  Also note that "smaps", what we read for
     determining core dump mappings, is even slower than "maps".  */
  xsnprintf (filename, sizeof filename, "/proc/%ld/task/%ld/maps", pid, pid);
  gdb::unique_xmalloc_ptr<char> data
    = target_fileio_read_stralloc (NULL, filename);
  if (data != NULL)
    {
      char *line;
      char *saveptr = NULL;

      for (line = strtok_r (data.get (), "\n", &saveptr);
	   line != NULL;
	   line = strtok_r (NULL, "\n", &saveptr))
	{
	  ULONGEST addr, endaddr;
	  const char *p = line;

	  addr = strtoulst (p, &p, 16);
	  if (addr == range->start)
	    {
	      if (*p == '-')
		p++;
	      endaddr = strtoulst (p, &p, 16);
	      range->length = endaddr - addr;
	      return 1;
	    }
	}
    }
  else
    warning (_("unable to open /proc file '%s'"), filename);

  return 0;
}

/* Implementation of the "vsyscall_range" gdbarch hook.  Handles
   caching, and defers the real work to linux_vsyscall_range_raw.  */

static int
linux_vsyscall_range (struct gdbarch *gdbarch, struct mem_range *range)
{
  struct linux_info *info = get_linux_inferior_data ();

  if (info->vsyscall_range_p == 0)
    {
      if (linux_vsyscall_range_raw (gdbarch, &info->vsyscall_range))
	info->vsyscall_range_p = 1;
      else
	info->vsyscall_range_p = -1;
    }

  if (info->vsyscall_range_p < 0)
    return 0;

  *range = info->vsyscall_range;
  return 1;
}

/* Symbols for linux_infcall_mmap's ARG_FLAGS; their Linux MAP_* system
   definitions would be dependent on compilation host.  */
#define GDB_MMAP_MAP_PRIVATE	0x02		/* Changes are private.  */
#define GDB_MMAP_MAP_ANONYMOUS	0x20		/* Don't use a file.  */

/* See gdbarch.sh 'infcall_mmap'.  */

static CORE_ADDR
linux_infcall_mmap (CORE_ADDR size, unsigned prot)
{
  struct objfile *objf;
  /* Do there still exist any Linux systems without "mmap64"?
     "mmap" uses 64-bit off_t on x86_64 and 32-bit off_t on i386 and x32.  */
  struct value *mmap_val = find_function_in_inferior ("mmap64", &objf);
  struct value *addr_val;
  struct gdbarch *gdbarch = get_objfile_arch (objf);
  CORE_ADDR retval;
  enum
    {
      ARG_ADDR, ARG_LENGTH, ARG_PROT, ARG_FLAGS, ARG_FD, ARG_OFFSET, ARG_LAST
    };
  struct value *arg[ARG_LAST];

  arg[ARG_ADDR] = value_from_pointer (builtin_type (gdbarch)->builtin_data_ptr,
				      0);
  /* Assuming sizeof (unsigned long) == sizeof (size_t).  */
  arg[ARG_LENGTH] = value_from_ulongest
		    (builtin_type (gdbarch)->builtin_unsigned_long, size);
  gdb_assert ((prot & ~(GDB_MMAP_PROT_READ | GDB_MMAP_PROT_WRITE
			| GDB_MMAP_PROT_EXEC))
	      == 0);
  arg[ARG_PROT] = value_from_longest (builtin_type (gdbarch)->builtin_int, prot);
  arg[ARG_FLAGS] = value_from_longest (builtin_type (gdbarch)->builtin_int,
				       GDB_MMAP_MAP_PRIVATE
				       | GDB_MMAP_MAP_ANONYMOUS);
  arg[ARG_FD] = value_from_longest (builtin_type (gdbarch)->builtin_int, -1);
  arg[ARG_OFFSET] = value_from_longest (builtin_type (gdbarch)->builtin_int64,
					0);
  addr_val = call_function_by_hand (mmap_val, NULL, ARG_LAST, arg);
  retval = value_as_address (addr_val);
  if (retval == (CORE_ADDR) -1)
    error (_("Failed inferior mmap call for %s bytes, errno is changed."),
	   pulongest (size));
  return retval;
}

/* See gdbarch.sh 'infcall_munmap'.  */

static void
linux_infcall_munmap (CORE_ADDR addr, CORE_ADDR size)
{
  struct objfile *objf;
  struct value *munmap_val = find_function_in_inferior ("munmap", &objf);
  struct value *retval_val;
  struct gdbarch *gdbarch = get_objfile_arch (objf);
  LONGEST retval;
  enum
    {
      ARG_ADDR, ARG_LENGTH, ARG_LAST
    };
  struct value *arg[ARG_LAST];

  arg[ARG_ADDR] = value_from_pointer (builtin_type (gdbarch)->builtin_data_ptr,
				      addr);
  /* Assuming sizeof (unsigned long) == sizeof (size_t).  */
  arg[ARG_LENGTH] = value_from_ulongest
		    (builtin_type (gdbarch)->builtin_unsigned_long, size);
  retval_val = call_function_by_hand (munmap_val, NULL, ARG_LAST, arg);
  retval = value_as_long (retval_val);
  if (retval != 0)
    warning (_("Failed inferior munmap call at %s for %s bytes, "
	       "errno is changed."),
	     hex_string (addr), pulongest (size));
}

/* See linux-tdep.h.  */

CORE_ADDR
linux_displaced_step_location (struct gdbarch *gdbarch)
{
  CORE_ADDR addr;
  int bp_len;

  /* Determine entry point from target auxiliary vector.  This avoids
     the need for symbols.  Also, when debugging a stand-alone SPU
     executable, entry_point_address () will point to an SPU
     local-store address and is thus not usable as displaced stepping
     location.  The auxiliary vector gets us the PowerPC-side entry
     point address instead.  */
  if (target_auxv_search (&current_target, AT_ENTRY, &addr) <= 0)
    throw_error (NOT_SUPPORTED_ERROR,
		 _("Cannot find AT_ENTRY auxiliary vector entry."));

  /* Make certain that the address points at real code, and not a
     function descriptor.  */
  addr = gdbarch_convert_from_func_ptr_addr (gdbarch, addr,
					     &current_target);

  /* Inferior calls also use the entry point as a breakpoint location.
     We don't want displaced stepping to interfere with those
     breakpoints, so leave space.  */
  gdbarch_breakpoint_from_pc (gdbarch, &addr, &bp_len);
  addr += bp_len * 2;

  return addr;
}

/* Display whether the gcore command is using the
   /proc/PID/coredump_filter file.  */

static void
show_use_coredump_filter (struct ui_file *file, int from_tty,
			  struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file, _("Use of /proc/PID/coredump_filter file to generate"
			    " corefiles is %s.\n"), value);
}

/* To be called from the various GDB_OSABI_LINUX handlers for the
   various GNU/Linux architectures and machine types.  */

void
linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  set_gdbarch_core_pid_to_str (gdbarch, linux_core_pid_to_str);
  set_gdbarch_info_proc (gdbarch, linux_info_proc);
  set_gdbarch_core_info_proc (gdbarch, linux_core_info_proc);
  set_gdbarch_core_xfer_siginfo (gdbarch, linux_core_xfer_siginfo);
  set_gdbarch_find_memory_regions (gdbarch, linux_find_memory_regions);
  set_gdbarch_make_corefile_notes (gdbarch, linux_make_corefile_notes);
  set_gdbarch_has_shared_address_space (gdbarch,
					linux_has_shared_address_space);
  set_gdbarch_gdb_signal_from_target (gdbarch,
				      linux_gdb_signal_from_target);
  set_gdbarch_gdb_signal_to_target (gdbarch,
				    linux_gdb_signal_to_target);
  set_gdbarch_vsyscall_range (gdbarch, linux_vsyscall_range);
  set_gdbarch_infcall_mmap (gdbarch, linux_infcall_mmap);
  set_gdbarch_infcall_munmap (gdbarch, linux_infcall_munmap);
  set_gdbarch_get_siginfo_type (gdbarch, linux_get_siginfo_type);
}

void
_initialize_linux_tdep (void)
{
  linux_gdbarch_data_handle =
    gdbarch_data_register_post_init (init_linux_gdbarch_data);

  /* Set a cache per-inferior.  */
  linux_inferior_data
    = register_inferior_data_with_cleanup (NULL, linux_inferior_data_cleanup);
  /* Observers used to invalidate the cache when needed.  */
  observer_attach_inferior_exit (invalidate_linux_cache_inf);
  observer_attach_inferior_appeared (invalidate_linux_cache_inf);

  add_setshow_boolean_cmd ("use-coredump-filter", class_files,
			   &use_coredump_filter, _("\
Set whether gcore should consider /proc/PID/coredump_filter."),
			   _("\
Show whether gcore should consider /proc/PID/coredump_filter."),
			   _("\
Use this command to set whether gcore should consider the contents\n\
of /proc/PID/coredump_filter when generating the corefile.  For more information\n\
about this file, refer to the manpage of core(5)."),
			   NULL, show_use_coredump_filter,
			   &setlist, &showlist);
}