aboutsummaryrefslogtreecommitdiff
path: root/gdb/procfs.c
blob: b5bda4dfb858f7e07e9c91d117872cf4999d2755 (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
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
/* Machine independent support for Solaris /proc (process file system) for GDB.

   Copyright (C) 1999-2024 Free Software Foundation, Inc.

   Written by Michael Snyder at Cygnus Solutions.
   Based on work by Fred Fish, Stu Grossman, Geoff Noer, and others.

   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 "extract-store-integer.h"
#include "inferior.h"
#include "infrun.h"
#include "target.h"
#include "gdbcore.h"
#include "elf-bfd.h"
#include "cli/cli-cmds.h"
#include "gdbthread.h"
#include "regcache.h"
#include "inf-child.h"
#include "nat/fork-inferior.h"
#include "gdbarch.h"

#include <sys/procfs.h>
#include <sys/fault.h>
#include <sys/syscall.h>
#include "gdbsupport/gdb_wait.h"
#include <signal.h>
#include <ctype.h>
#include "gdb_bfd.h"
#include "auxv.h"
#include "procfs.h"
#include "observable.h"
#include "gdbsupport/scoped_fd.h"
#include "gdbsupport/pathstuff.h"
#include "gdbsupport/buildargv.h"
#include "cli/cli-style.h"

/* This module provides the interface between GDB and the
   /proc file system, which is used on many versions of Unix
   as a means for debuggers to control other processes.

   /proc works by imitating a file system: you open a simulated file
   that represents the process you wish to interact with, and perform
   operations on that "file" in order to examine or change the state
   of the other process.

   The most important thing to know about /proc and this module is
   that there are two very different interfaces to /proc:

     One that uses the ioctl system call, and another that uses read
     and write system calls.

   This module supports only the Solaris version of the read/write
   interface.  */

#include <sys/types.h>
#include <dirent.h>

#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>

/* Note: procfs-utils.h must be included after the above system header
   files, because it redefines various system calls using macros.
   This may be incompatible with the prototype declarations.  */

#include "proc-utils.h"

/* Prototypes for supply_gregset etc.  */
#include "gregset.h"

/* =================== TARGET_OPS "MODULE" =================== */

/* This module defines the GDB target vector and its methods.  */


static enum target_xfer_status procfs_xfer_memory (gdb_byte *,
						   const gdb_byte *,
						   ULONGEST, ULONGEST,
						   ULONGEST *);

class procfs_target final : public inf_child_target
{
public:
  void create_inferior (const char *, const std::string &,
			char **, int) override;

  void kill () override;

  void mourn_inferior () override;

  void attach (const char *, int) override;
  void detach (inferior *inf, int) override;

  void resume (ptid_t, int, enum gdb_signal) override;
  ptid_t wait (ptid_t, struct target_waitstatus *, target_wait_flags) override;

  void fetch_registers (struct regcache *, int) override;
  void store_registers (struct regcache *, int) override;

  enum target_xfer_status xfer_partial (enum target_object object,
					const char *annex,
					gdb_byte *readbuf,
					const gdb_byte *writebuf,
					ULONGEST offset, ULONGEST len,
					ULONGEST *xfered_len) override;

  void pass_signals (gdb::array_view<const unsigned char>) override;

  void files_info () override;

  void update_thread_list () override;

  bool thread_alive (ptid_t ptid) override;

  std::string pid_to_str (ptid_t) override;

  const char *pid_to_exec_file (int pid) override;

  thread_control_capabilities get_thread_control_capabilities () override
  { return tc_schedlock; }

  /* find_memory_regions support method for gcore */
  int find_memory_regions (find_memory_region_ftype func, void *data)
    override;

  gdb::unique_xmalloc_ptr<char> make_corefile_notes (bfd *, int *) override;

  bool info_proc (const char *, enum info_proc_what) override;

#if PR_MODEL_NATIVE == PR_MODEL_LP64
  int auxv_parse (const gdb_byte **readptr,
		  const gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp)
    override;
#endif

  bool stopped_by_watchpoint () override;

  int insert_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
			 struct expression *) override;

  int remove_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
			 struct expression *) override;

  int region_ok_for_hw_watchpoint (CORE_ADDR, int) override;

  int can_use_hw_breakpoint (enum bptype, int, int) override;
  bool stopped_data_address (CORE_ADDR *) override;

  void procfs_init_inferior (int pid);
};

static procfs_target the_procfs_target;

#if PR_MODEL_NATIVE == PR_MODEL_LP64
/* When GDB is built as 64-bit application on Solaris, the auxv data
   is presented in 64-bit format.  We need to provide a custom parser
   to handle that.  */
int
procfs_target::auxv_parse (const gdb_byte **readptr,
			   const gdb_byte *endptr, CORE_ADDR *typep,
			   CORE_ADDR *valp)
{
  bfd_endian byte_order = gdbarch_byte_order (current_inferior ()->arch ());
  const gdb_byte *ptr = *readptr;

  if (endptr == ptr)
    return 0;

  if (endptr - ptr < 8 * 2)
    return -1;

  *typep = extract_unsigned_integer (ptr, 4, byte_order);
  ptr += 8;
  /* The size of data is always 64-bit.  If the application is 32-bit,
     it will be zero extended, as expected.  */
  *valp = extract_unsigned_integer (ptr, 8, byte_order);
  ptr += 8;

  *readptr = ptr;
  return 1;
}
#endif

/* =================== END, TARGET_OPS "MODULE" =================== */

/* =================== STRUCT PROCINFO "MODULE" =================== */

     /* FIXME: this comment will soon be out of date W.R.T. threads.  */

/* The procinfo struct is a wrapper to hold all the state information
   concerning a /proc process.  There should be exactly one procinfo
   for each process, and since GDB currently can debug only one
   process at a time, that means there should be only one procinfo.
   All of the LWP's of a process can be accessed indirectly thru the
   single process procinfo.

   However, against the day when GDB may debug more than one process,
   this data structure is kept in a list (which for now will hold no
   more than one member), and many functions will have a pointer to a
   procinfo as an argument.

   There will be a separate procinfo structure for use by the (not yet
   implemented) "info proc" command, so that we can print useful
   information about any random process without interfering with the
   inferior's procinfo information.  */

/* format strings for /proc paths */
#define CTL_PROC_NAME_FMT    "/proc/%d/ctl"
#define AS_PROC_NAME_FMT     "/proc/%d/as"
#define MAP_PROC_NAME_FMT    "/proc/%d/map"
#define STATUS_PROC_NAME_FMT "/proc/%d/status"
#define MAX_PROC_NAME_SIZE sizeof("/proc/999999/lwp/0123456789/lwpstatus")

typedef struct procinfo {
  struct procinfo *next;
  int pid;			/* Process ID    */
  int tid;			/* Thread/LWP id */

  /* process state */
  int was_stopped;
  int ignore_next_sigstop;

  int ctl_fd;			/* File descriptor for /proc control file */
  int status_fd;		/* File descriptor for /proc status file */
  int as_fd;			/* File descriptor for /proc as file */

  char pathname[MAX_PROC_NAME_SIZE];	/* Pathname to /proc entry */

  fltset_t saved_fltset;	/* Saved traced hardware fault set */
  sigset_t saved_sigset;	/* Saved traced signal set */
  sigset_t saved_sighold;	/* Saved held signal set */
  sysset_t *saved_exitset;	/* Saved traced system call exit set */
  sysset_t *saved_entryset;	/* Saved traced system call entry set */

  pstatus_t prstatus;		/* Current process status info */

  struct procinfo *thread_list;

  int status_valid : 1;
  int gregs_valid  : 1;
  int fpregs_valid : 1;
  int threads_valid: 1;
} procinfo;

/* Function prototypes for procinfo module: */

static procinfo *find_procinfo_or_die (int pid, int tid);
static procinfo *find_procinfo (int pid, int tid);
static procinfo *create_procinfo (int pid, int tid);
static void destroy_procinfo (procinfo *p);
static void dead_procinfo (procinfo *p, const char *msg, int killp);
static int open_procinfo_files (procinfo *p, int which);
static void close_procinfo_files (procinfo *p);

static int iterate_over_mappings
  (procinfo *pi, find_memory_region_ftype child_func, void *data,
   int (*func) (struct prmap *map, find_memory_region_ftype child_func,
		void *data));

/* The head of the procinfo list: */
static procinfo *procinfo_list;

/* Search the procinfo list.  Return a pointer to procinfo, or NULL if
   not found.  */

static procinfo *
find_procinfo (int pid, int tid)
{
  procinfo *pi;

  for (pi = procinfo_list; pi; pi = pi->next)
    if (pi->pid == pid)
      break;

  if (pi)
    if (tid)
      {
	/* Don't check threads_valid.  If we're updating the
	   thread_list, we want to find whatever threads are already
	   here.  This means that in general it is the caller's
	   responsibility to check threads_valid and update before
	   calling find_procinfo, if the caller wants to find a new
	   thread.  */

	for (pi = pi->thread_list; pi; pi = pi->next)
	  if (pi->tid == tid)
	    break;
      }

  return pi;
}

/* Calls find_procinfo, but errors on failure.  */

static procinfo *
find_procinfo_or_die (int pid, int tid)
{
  procinfo *pi = find_procinfo (pid, tid);

  if (pi == NULL)
    {
      if (tid)
	error (_("procfs: couldn't find pid %d "
		 "(kernel thread %d) in procinfo list."),
	       pid, tid);
      else
	error (_("procfs: couldn't find pid %d in procinfo list."), pid);
    }
  return pi;
}

/* Wrapper for `open'.  The appropriate open call is attempted; if
   unsuccessful, it will be retried as many times as needed for the
   EAGAIN and EINTR conditions.

   For other conditions, retry the open a limited number of times.  In
   addition, a short sleep is imposed prior to retrying the open.  The
   reason for this sleep is to give the kernel a chance to catch up
   and create the file in question in the event that GDB "wins" the
   race to open a file before the kernel has created it.  */

static int
open_with_retry (const char *pathname, int flags)
{
  int retries_remaining, status;

  retries_remaining = 2;

  while (1)
    {
      status = open (pathname, flags);

      if (status >= 0 || retries_remaining == 0)
	break;
      else if (errno != EINTR && errno != EAGAIN)
	{
	  retries_remaining--;
	  sleep (1);
	}
    }

  return status;
}

/* Open the file descriptor for the process or LWP.  We only open the
   control file descriptor; the others are opened lazily as needed.
   Returns the file descriptor, or zero for failure.  */

enum { FD_CTL, FD_STATUS, FD_AS };

static int
open_procinfo_files (procinfo *pi, int which)
{
  char tmp[MAX_PROC_NAME_SIZE];
  int  fd;

  /* This function is getting ALMOST long enough to break up into
     several.  Here is some rationale:

     There are several file descriptors that may need to be open
     for any given process or LWP.  The ones we're interested in are:
	 - control	 (ctl)	  write-only	change the state
	 - status	 (status) read-only	query the state
	 - address space (as)	  read/write	access memory
	 - map		 (map)	  read-only	virtual addr map
     Most of these are opened lazily as they are needed.
     The pathnames for the 'files' for an LWP look slightly
     different from those of a first-class process:
	 Pathnames for a process (<proc-id>):
	   /proc/<proc-id>/ctl
	   /proc/<proc-id>/status
	   /proc/<proc-id>/as
	   /proc/<proc-id>/map
	 Pathnames for an LWP (lwp-id):
	   /proc/<proc-id>/lwp/<lwp-id>/lwpctl
	   /proc/<proc-id>/lwp/<lwp-id>/lwpstatus
     An LWP has no map or address space file descriptor, since
     the memory map and address space are shared by all LWPs.  */

  /* In this case, there are several different file descriptors that
     we might be asked to open.  The control file descriptor will be
     opened early, but the others will be opened lazily as they are
     needed.  */

  strcpy (tmp, pi->pathname);
  switch (which) {	/* Which file descriptor to open?  */
  case FD_CTL:
    if (pi->tid)
      strcat (tmp, "/lwpctl");
    else
      strcat (tmp, "/ctl");
    fd = open_with_retry (tmp, O_WRONLY);
    if (fd < 0)
      return 0;		/* fail */
    pi->ctl_fd = fd;
    break;
  case FD_AS:
    if (pi->tid)
      return 0;		/* There is no 'as' file descriptor for an lwp.  */
    strcat (tmp, "/as");
    fd = open_with_retry (tmp, O_RDWR);
    if (fd < 0)
      return 0;		/* fail */
    pi->as_fd = fd;
    break;
  case FD_STATUS:
    if (pi->tid)
      strcat (tmp, "/lwpstatus");
    else
      strcat (tmp, "/status");
    fd = open_with_retry (tmp, O_RDONLY);
    if (fd < 0)
      return 0;		/* fail */
    pi->status_fd = fd;
    break;
  default:
    return 0;		/* unknown file descriptor */
  }

  return 1;		/* success */
}

/* Allocate a data structure and link it into the procinfo list.
   First tries to find a pre-existing one (FIXME: why?).  Returns the
   pointer to new procinfo struct.  */

static procinfo *
create_procinfo (int pid, int tid)
{
  procinfo *pi, *parent = NULL;

  pi = find_procinfo (pid, tid);
  if (pi != NULL)
    return pi;			/* Already exists, nothing to do.  */

  /* Find parent before doing malloc, to save having to cleanup.  */
  if (tid != 0)
    parent = find_procinfo_or_die (pid, 0);	/* FIXME: should I
						   create it if it
						   doesn't exist yet?  */

  pi = XNEW (procinfo);
  memset (pi, 0, sizeof (procinfo));
  pi->pid = pid;
  pi->tid = tid;

  pi->saved_entryset = XNEW (sysset_t);
  pi->saved_exitset = XNEW (sysset_t);

  /* Chain into list.  */
  if (tid == 0)
    {
      xsnprintf (pi->pathname, sizeof (pi->pathname), "/proc/%d", pid);
      pi->next = procinfo_list;
      procinfo_list = pi;
    }
  else
    {
      xsnprintf (pi->pathname, sizeof (pi->pathname), "/proc/%d/lwp/%d",
		 pid, tid);
      pi->next = parent->thread_list;
      parent->thread_list = pi;
    }
  return pi;
}

/* Close all file descriptors associated with the procinfo.  */

static void
close_procinfo_files (procinfo *pi)
{
  if (pi->ctl_fd > 0)
    close (pi->ctl_fd);
  if (pi->as_fd > 0)
    close (pi->as_fd);
  if (pi->status_fd > 0)
    close (pi->status_fd);
  pi->ctl_fd = pi->as_fd = pi->status_fd = 0;
}

/* Destructor function.  Close, unlink and deallocate the object.  */

static void
destroy_one_procinfo (procinfo **list, procinfo *pi)
{
  procinfo *ptr;

  /* Step one: unlink the procinfo from its list.  */
  if (pi == *list)
    *list = pi->next;
  else
    for (ptr = *list; ptr; ptr = ptr->next)
      if (ptr->next == pi)
	{
	  ptr->next =  pi->next;
	  break;
	}

  /* Step two: close any open file descriptors.  */
  close_procinfo_files (pi);

  /* Step three: free the memory.  */
  xfree (pi->saved_entryset);
  xfree (pi->saved_exitset);
  xfree (pi);
}

static void
destroy_procinfo (procinfo *pi)
{
  procinfo *tmp;

  if (pi->tid != 0)	/* Destroy a thread procinfo.  */
    {
      tmp = find_procinfo (pi->pid, 0);	/* Find the parent process.  */
      destroy_one_procinfo (&tmp->thread_list, pi);
    }
  else			/* Destroy a process procinfo and all its threads.  */
    {
      /* First destroy the children, if any; */
      while (pi->thread_list != NULL)
	destroy_one_procinfo (&pi->thread_list, pi->thread_list);
      /* Then destroy the parent.  Genocide!!!  */
      destroy_one_procinfo (&procinfo_list, pi);
    }
}

/* A deleter that calls destroy_procinfo.  */
struct procinfo_deleter
{
  void operator() (procinfo *pi) const
  {
    destroy_procinfo (pi);
  }
};

typedef std::unique_ptr<procinfo, procinfo_deleter> procinfo_up;

enum { NOKILL, KILL };

/* To be called on a non_recoverable error for a procinfo.  Prints
   error messages, optionally sends a SIGKILL to the process, then
   destroys the data structure.  */

static void
dead_procinfo (procinfo *pi, const char *msg, int kill_p)
{
  warning_filename_and_errno (pi->pathname, errno);
  if (kill_p == KILL)
    kill (pi->pid, SIGKILL);

  destroy_procinfo (pi);
  error ("%s", msg);
}

/* =================== END, STRUCT PROCINFO "MODULE" =================== */

/* ===================  /proc "MODULE" =================== */

/* This "module" is the interface layer between the /proc system API
   and the gdb target vector functions.  This layer consists of access
   functions that encapsulate each of the basic operations that we
   need to use from the /proc API.

   The main motivation for this layer is to hide the fact that there
   were two very different implementations of the /proc API.  */

static long proc_flags (procinfo *pi);
static int proc_why (procinfo *pi);
static int proc_what (procinfo *pi);
static int proc_set_current_signal (procinfo *pi, int signo);
static int proc_get_current_thread (procinfo *pi);
static int proc_iterate_over_threads
  (procinfo *pi,
   int (*func) (procinfo *, procinfo *, void *),
   void *ptr);
static void proc_resume (procinfo *pi, ptid_t scope_ptid,
			 int step, enum gdb_signal signo);

static void
proc_warn (procinfo *pi, const char *func, int line)
{
  int saved_errno = errno;
  warning ("procfs: %s line %d, %ps: %s",
	   func, line, styled_string (file_name_style.style (),
				      pi->pathname),
	   safe_strerror (saved_errno));
}

static void
proc_error (procinfo *pi, const char *func, int line)
{
  int saved_errno = errno;
  error ("procfs: %s line %d, %s: %s",
	 func, line, pi->pathname, safe_strerror (saved_errno));
}

/* Updates the status struct in the procinfo.  There is a 'valid'
   flag, to let other functions know when this function needs to be
   called (so the status is only read when it is needed).  The status
   file descriptor is also only opened when it is needed.  Returns
   non-zero for success, zero for failure.  */

static int
proc_get_status (procinfo *pi)
{
  /* Status file descriptor is opened "lazily".  */
  if (pi->status_fd == 0 && open_procinfo_files (pi, FD_STATUS) == 0)
    {
      pi->status_valid = 0;
      return 0;
    }

  if (lseek (pi->status_fd, 0, SEEK_SET) < 0)
    pi->status_valid = 0;			/* fail */
  else
    {
      /* Sigh... I have to read a different data structure,
	 depending on whether this is a main process or an LWP.  */
      if (pi->tid)
	pi->status_valid = (read (pi->status_fd,
				  (char *) &pi->prstatus.pr_lwp,
				  sizeof (lwpstatus_t))
			    == sizeof (lwpstatus_t));
      else
	{
	  pi->status_valid = (read (pi->status_fd,
				    (char *) &pi->prstatus,
				    sizeof (pstatus_t))
			      == sizeof (pstatus_t));
	}
    }

  if (pi->status_valid)
    {
      PROC_PRETTYFPRINT_STATUS (proc_flags (pi),
				proc_why (pi),
				proc_what (pi),
				proc_get_current_thread (pi));
    }

  /* The status struct includes general regs, so mark them valid too.  */
  pi->gregs_valid  = pi->status_valid;
  /* In the read/write multiple-fd model, the status struct includes
     the fp regs too, so mark them valid too.  */
  pi->fpregs_valid = pi->status_valid;
  return pi->status_valid;	/* True if success, false if failure.  */
}

/* Returns the process flags (pr_flags field).  */

static long
proc_flags (procinfo *pi)
{
  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;	/* FIXME: not a good failure value (but what is?)  */

  return pi->prstatus.pr_lwp.pr_flags;
}

/* Returns the pr_why field (why the process stopped).  */

static int
proc_why (procinfo *pi)
{
  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;	/* FIXME: not a good failure value (but what is?)  */

  return pi->prstatus.pr_lwp.pr_why;
}

/* Returns the pr_what field (details of why the process stopped).  */

static int
proc_what (procinfo *pi)
{
  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;	/* FIXME: not a good failure value (but what is?)  */

  return pi->prstatus.pr_lwp.pr_what;
}

/* This function is only called when PI is stopped by a watchpoint.
   Assuming the OS supports it, write to *ADDR the data address which
   triggered it and return 1.  Return 0 if it is not possible to know
   the address.  */

static int
proc_watchpoint_address (procinfo *pi, CORE_ADDR *addr)
{
  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;

  gdbarch *arch = current_inferior ()->arch ();
  *addr = gdbarch_pointer_to_address
	    (arch, builtin_type (arch)->builtin_data_ptr,
	     (gdb_byte *) &pi->prstatus.pr_lwp.pr_info.si_addr);
  return 1;
}

/* Returns the pr_nsysarg field (number of args to the current
   syscall).  */

static int
proc_nsysarg (procinfo *pi)
{
  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;

  return pi->prstatus.pr_lwp.pr_nsysarg;
}

/* Returns the pr_sysarg field (pointer to the arguments of current
   syscall).  */

static long *
proc_sysargs (procinfo *pi)
{
  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return NULL;

  return (long *) &pi->prstatus.pr_lwp.pr_sysarg;
}

/* Set or reset any of the following process flags:
      PR_FORK	-- forked child will inherit trace flags
      PR_RLC	-- traced process runs when last /proc file closed.
      PR_KLC    -- traced process is killed when last /proc file closed.
      PR_ASYNC	-- LWP's get to run/stop independently.

   This function is done using read/write [PCSET/PCRESET/PCUNSET].

   Arguments:
      pi   -- the procinfo
      flag -- one of PR_FORK, PR_RLC, or PR_ASYNC
      mode -- 1 for set, 0 for reset.

   Returns non-zero for success, zero for failure.  */

enum { FLAG_RESET, FLAG_SET };

static int
proc_modify_flag (procinfo *pi, long flag, long mode)
{
  long win = 0;		/* default to fail */

  /* These operations affect the process as a whole, and applying them
     to an individual LWP has the same meaning as applying them to the
     main process.  Therefore, if we're ever called with a pointer to
     an LWP's procinfo, let's substitute the process's procinfo and
     avoid opening the LWP's file descriptor unnecessarily.  */

  if (pi->pid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  procfs_ctl_t arg[2];

  if (mode == FLAG_SET)	/* Set the flag (RLC, FORK, or ASYNC).  */
    arg[0] = PCSET;
  else			/* Reset the flag.  */
    arg[0] = PCUNSET;

  arg[1] = flag;
  win = (write (pi->ctl_fd, (void *) &arg, sizeof (arg)) == sizeof (arg));

  /* The above operation renders the procinfo's cached pstatus
     obsolete.  */
  pi->status_valid = 0;

  if (!win)
    warning (_("procfs: modify_flag failed to turn %s %s"),
	     flag == PR_FORK  ? "PR_FORK"  :
	     flag == PR_RLC   ? "PR_RLC"   :
	     flag == PR_ASYNC ? "PR_ASYNC" :
	     flag == PR_KLC   ? "PR_KLC"   :
	     "<unknown flag>",
	     mode == FLAG_RESET ? "off" : "on");

  return win;
}

/* Set the run_on_last_close flag.  Process with all threads will
   become runnable when debugger closes all /proc fds.  Returns
   non-zero for success, zero for failure.  */

static int
proc_set_run_on_last_close (procinfo *pi)
{
  return proc_modify_flag (pi, PR_RLC, FLAG_SET);
}

/* Reset the run_on_last_close flag.  The process will NOT become
   runnable when debugger closes its file handles.  Returns non-zero
   for success, zero for failure.  */

static int
proc_unset_run_on_last_close (procinfo *pi)
{
  return proc_modify_flag (pi, PR_RLC, FLAG_RESET);
}

/* Reset inherit_on_fork flag.  If the process forks a child while we
   are registered for events in the parent, then we will NOT receive
   events from the child.  Returns non-zero for success, zero for
   failure.  */

static int
proc_unset_inherit_on_fork (procinfo *pi)
{
  return proc_modify_flag (pi, PR_FORK, FLAG_RESET);
}

/* Set PR_ASYNC flag.  If one LWP stops because of a debug event
   (signal etc.), the remaining LWPs will continue to run.  Returns
   non-zero for success, zero for failure.  */

static int
proc_set_async (procinfo *pi)
{
  return proc_modify_flag (pi, PR_ASYNC, FLAG_SET);
}

/* Reset PR_ASYNC flag.  If one LWP stops because of a debug event
   (signal etc.), then all other LWPs will stop as well.  Returns
   non-zero for success, zero for failure.  */

static int
proc_unset_async (procinfo *pi)
{
  return proc_modify_flag (pi, PR_ASYNC, FLAG_RESET);
}

/* Request the process/LWP to stop.  Does not wait.  Returns non-zero
   for success, zero for failure.  */

static int
proc_stop_process (procinfo *pi)
{
  int win;

  /* We might conceivably apply this operation to an LWP, and the
     LWP's ctl file descriptor might not be open.  */

  if (pi->ctl_fd == 0 && open_procinfo_files (pi, FD_CTL) == 0)
    return 0;
  else
    {
      procfs_ctl_t cmd = PCSTOP;

      win = (write (pi->ctl_fd, (char *) &cmd, sizeof (cmd)) == sizeof (cmd));
    }

  return win;
}

/* Wait for the process or LWP to stop (block until it does).  Returns
   non-zero for success, zero for failure.  */

static int
proc_wait_for_stop (procinfo *pi)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  procfs_ctl_t cmd = PCWSTOP;

  set_sigint_trap ();

  win = (write (pi->ctl_fd, (char *) &cmd, sizeof (cmd)) == sizeof (cmd));

  clear_sigint_trap ();

  /* We been runnin' and we stopped -- need to update status.  */
  pi->status_valid = 0;

  return win;
}

/* Make the process or LWP runnable.

   Options (not all are implemented):
     - single-step
     - clear current fault
     - clear current signal
     - abort the current system call
     - stop as soon as finished with system call

   Always clears the current fault.  PI is the process or LWP to
   operate on.  If STEP is true, set the process or LWP to trap after
   one instruction.  If SIGNO is zero, clear the current signal if
   any; if non-zero, set the current signal to this one.  Returns
   non-zero for success, zero for failure.  */

static int
proc_run_process (procinfo *pi, int step, int signo)
{
  int win;
  int runflags;

  /* We will probably have to apply this operation to individual
     threads, so make sure the control file descriptor is open.  */

  if (pi->ctl_fd == 0 && open_procinfo_files (pi, FD_CTL) == 0)
    return 0;

  runflags    = PRCFAULT;	/* Always clear current fault.  */
  if (step)
    runflags |= PRSTEP;
  if (signo == 0)
    runflags |= PRCSIG;
  else if (signo != -1)		/* -1 means do nothing W.R.T. signals.  */
    proc_set_current_signal (pi, signo);

  procfs_ctl_t cmd[2];

  cmd[0]  = PCRUN;
  cmd[1]  = runflags;
  win = (write (pi->ctl_fd, (char *) &cmd, sizeof (cmd)) == sizeof (cmd));

  return win;
}

/* Register to trace signals in the process or LWP.  Returns non-zero
   for success, zero for failure.  */

static int
proc_set_traced_signals (procinfo *pi, sigset_t *sigset)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  struct {
    procfs_ctl_t cmd;
    /* Use char array to avoid alignment issues.  */
    char sigset[sizeof (sigset_t)];
  } arg;

  arg.cmd = PCSTRACE;
  memcpy (&arg.sigset, sigset, sizeof (sigset_t));

  win = (write (pi->ctl_fd, (char *) &arg, sizeof (arg)) == sizeof (arg));

  /* The above operation renders the procinfo's cached pstatus obsolete.  */
  pi->status_valid = 0;

  if (!win)
    warning (_("procfs: set_traced_signals failed"));
  return win;
}

/* Register to trace hardware faults in the process or LWP.  Returns
   non-zero for success, zero for failure.  */

static int
proc_set_traced_faults (procinfo *pi, fltset_t *fltset)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  struct {
    procfs_ctl_t cmd;
    /* Use char array to avoid alignment issues.  */
    char fltset[sizeof (fltset_t)];
  } arg;

  arg.cmd = PCSFAULT;
  memcpy (&arg.fltset, fltset, sizeof (fltset_t));

  win = (write (pi->ctl_fd, (char *) &arg, sizeof (arg)) == sizeof (arg));

  /* The above operation renders the procinfo's cached pstatus obsolete.  */
  pi->status_valid = 0;

  return win;
}

/* Register to trace entry to system calls in the process or LWP.
   Returns non-zero for success, zero for failure.  */

static int
proc_set_traced_sysentry (procinfo *pi, sysset_t *sysset)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  struct {
    procfs_ctl_t cmd;
    /* Use char array to avoid alignment issues.  */
    char sysset[sizeof (sysset_t)];
  } arg;

  arg.cmd = PCSENTRY;
  memcpy (&arg.sysset, sysset, sizeof (sysset_t));

  win = (write (pi->ctl_fd, (char *) &arg, sizeof (arg)) == sizeof (arg));

  /* The above operation renders the procinfo's cached pstatus
     obsolete.  */
  pi->status_valid = 0;

  return win;
}

/* Register to trace exit from system calls in the process or LWP.
   Returns non-zero for success, zero for failure.  */

static int
proc_set_traced_sysexit (procinfo *pi, sysset_t *sysset)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  struct gdb_proc_ctl_pcsexit {
    procfs_ctl_t cmd;
    /* Use char array to avoid alignment issues.  */
    char sysset[sizeof (sysset_t)];
  } arg;

  arg.cmd = PCSEXIT;
  memcpy (&arg.sysset, sysset, sizeof (sysset_t));

  win = (write (pi->ctl_fd, (char *) &arg, sizeof (arg)) == sizeof (arg));

  /* The above operation renders the procinfo's cached pstatus
     obsolete.  */
  pi->status_valid = 0;

  return win;
}

/* Specify the set of blocked / held signals in the process or LWP.
   Returns non-zero for success, zero for failure.  */

static int
proc_set_held_signals (procinfo *pi, sigset_t *sighold)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  struct {
    procfs_ctl_t cmd;
    /* Use char array to avoid alignment issues.  */
    char hold[sizeof (sigset_t)];
  } arg;

  arg.cmd  = PCSHOLD;
  memcpy (&arg.hold, sighold, sizeof (sigset_t));
  win = (write (pi->ctl_fd, (void *) &arg, sizeof (arg)) == sizeof (arg));

  /* The above operation renders the procinfo's cached pstatus
     obsolete.  */
  pi->status_valid = 0;

  return win;
}

/* Returns the set of signals that are held / blocked.  Will also copy
   the sigset if SAVE is non-zero.  */

static sigset_t *
proc_get_held_signals (procinfo *pi, sigset_t *save)
{
  sigset_t *ret = NULL;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return NULL;

  ret = &pi->prstatus.pr_lwp.pr_lwphold;
  if (save && ret)
    memcpy (save, ret, sizeof (sigset_t));

  return ret;
}

/* Returns the set of signals that are traced / debugged.  Will also
   copy the sigset if SAVE is non-zero.  */

static sigset_t *
proc_get_traced_signals (procinfo *pi, sigset_t *save)
{
  sigset_t *ret = NULL;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return NULL;

  ret = &pi->prstatus.pr_sigtrace;
  if (save && ret)
    memcpy (save, ret, sizeof (sigset_t));

  return ret;
}

/* Returns the set of hardware faults that are traced /debugged.  Will
   also copy the faultset if SAVE is non-zero.  */

static fltset_t *
proc_get_traced_faults (procinfo *pi, fltset_t *save)
{
  fltset_t *ret = NULL;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return NULL;

  ret = &pi->prstatus.pr_flttrace;
  if (save && ret)
    memcpy (save, ret, sizeof (fltset_t));

  return ret;
}

/* Returns the set of syscalls that are traced /debugged on entry.
   Will also copy the syscall set if SAVE is non-zero.  */

static sysset_t *
proc_get_traced_sysentry (procinfo *pi, sysset_t *save)
{
  sysset_t *ret = NULL;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return NULL;

  ret = &pi->prstatus.pr_sysentry;
  if (save && ret)
    memcpy (save, ret, sizeof (sysset_t));

  return ret;
}

/* Returns the set of syscalls that are traced /debugged on exit.
   Will also copy the syscall set if SAVE is non-zero.  */

static sysset_t *
proc_get_traced_sysexit (procinfo *pi, sysset_t *save)
{
  sysset_t *ret = NULL;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return NULL;

  ret = &pi->prstatus.pr_sysexit;
  if (save && ret)
    memcpy (save, ret, sizeof (sysset_t));

  return ret;
}

/* The current fault (if any) is cleared; the associated signal will
   not be sent to the process or LWP when it resumes.  Returns
   non-zero for success, zero for failure.  */

static int
proc_clear_current_fault (procinfo *pi)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  procfs_ctl_t cmd = PCCFAULT;

  win = (write (pi->ctl_fd, (void *) &cmd, sizeof (cmd)) == sizeof (cmd));

  return win;
}

/* Set the "current signal" that will be delivered next to the
   process.  NOTE: semantics are different from those of KILL.  This
   signal will be delivered to the process or LWP immediately when it
   is resumed (even if the signal is held/blocked); it will NOT
   immediately cause another event of interest, and will NOT first
   trap back to the debugger.  Returns non-zero for success, zero for
   failure.  */

static int
proc_set_current_signal (procinfo *pi, int signo)
{
  int win;
  struct {
    procfs_ctl_t cmd;
    /* Use char array to avoid alignment issues.  */
    char sinfo[sizeof (siginfo_t)];
  } arg;
  siginfo_t mysinfo;
  process_stratum_target *wait_target;
  ptid_t wait_ptid;
  struct target_waitstatus wait_status;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  /* The pointer is just a type alias.  */
  get_last_target_status (&wait_target, &wait_ptid, &wait_status);
  if (wait_target == &the_procfs_target
      && wait_ptid == inferior_ptid
      && wait_status.kind () == TARGET_WAITKIND_STOPPED
      && wait_status.sig () == gdb_signal_from_host (signo)
      && proc_get_status (pi)
      && pi->prstatus.pr_lwp.pr_info.si_signo == signo
      )
    /* Use the siginfo associated with the signal being
       redelivered.  */
    memcpy (arg.sinfo, &pi->prstatus.pr_lwp.pr_info, sizeof (siginfo_t));
  else
    {
      mysinfo.si_signo = signo;
      mysinfo.si_code  = 0;
      mysinfo.si_pid   = getpid ();       /* ?why? */
      mysinfo.si_uid   = getuid ();       /* ?why? */
      memcpy (arg.sinfo, &mysinfo, sizeof (siginfo_t));
    }

  arg.cmd = PCSSIG;
  win = (write (pi->ctl_fd, (void *) &arg, sizeof (arg))  == sizeof (arg));

  return win;
}

/* The current signal (if any) is cleared, and is not sent to the
   process or LWP when it resumes.  Returns non-zero for success, zero
   for failure.  */

static int
proc_clear_current_signal (procinfo *pi)
{
  int win;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  struct {
    procfs_ctl_t cmd;
    /* Use char array to avoid alignment issues.  */
    char sinfo[sizeof (siginfo_t)];
  } arg;
  siginfo_t mysinfo;

  arg.cmd = PCSSIG;
  /* The pointer is just a type alias.  */
  mysinfo.si_signo = 0;
  mysinfo.si_code  = 0;
  mysinfo.si_errno = 0;
  mysinfo.si_pid   = getpid ();       /* ?why? */
  mysinfo.si_uid   = getuid ();       /* ?why? */
  memcpy (arg.sinfo, &mysinfo, sizeof (siginfo_t));

  win = (write (pi->ctl_fd, (void *) &arg, sizeof (arg)) == sizeof (arg));

  return win;
}

/* Return the general-purpose registers for the process or LWP
   corresponding to PI.  Upon failure, return NULL.  */

static gdb_gregset_t *
proc_get_gregs (procinfo *pi)
{
  if (!pi->status_valid || !pi->gregs_valid)
    if (!proc_get_status (pi))
      return NULL;

  return &pi->prstatus.pr_lwp.pr_reg;
}

/* Return the general-purpose registers for the process or LWP
   corresponding to PI.  Upon failure, return NULL.  */

static gdb_fpregset_t *
proc_get_fpregs (procinfo *pi)
{
  if (!pi->status_valid || !pi->fpregs_valid)
    if (!proc_get_status (pi))
      return NULL;

  return &pi->prstatus.pr_lwp.pr_fpreg;
}

/* Write the general-purpose registers back to the process or LWP
   corresponding to PI.  Return non-zero for success, zero for
   failure.  */

static int
proc_set_gregs (procinfo *pi)
{
  gdb_gregset_t *gregs;
  int win;

  gregs = proc_get_gregs (pi);
  if (gregs == NULL)
    return 0;			/* proc_get_regs has already warned.  */

  if (pi->ctl_fd == 0 && open_procinfo_files (pi, FD_CTL) == 0)
    return 0;
  else
    {
      struct {
	procfs_ctl_t cmd;
	/* Use char array to avoid alignment issues.  */
	char gregs[sizeof (gdb_gregset_t)];
      } arg;

      arg.cmd = PCSREG;
      memcpy (&arg.gregs, gregs, sizeof (arg.gregs));
      win = (write (pi->ctl_fd, (void *) &arg, sizeof (arg)) == sizeof (arg));
    }

  /* Policy: writing the registers invalidates our cache.  */
  pi->gregs_valid = 0;
  return win;
}

/* Write the floating-pointer registers back to the process or LWP
   corresponding to PI.  Return non-zero for success, zero for
   failure.  */

static int
proc_set_fpregs (procinfo *pi)
{
  gdb_fpregset_t *fpregs;
  int win;

  fpregs = proc_get_fpregs (pi);
  if (fpregs == NULL)
    return 0;			/* proc_get_fpregs has already warned.  */

  if (pi->ctl_fd == 0 && open_procinfo_files (pi, FD_CTL) == 0)
    return 0;
  else
    {
      struct {
	procfs_ctl_t cmd;
	/* Use char array to avoid alignment issues.  */
	char fpregs[sizeof (gdb_fpregset_t)];
      } arg;

      arg.cmd = PCSFPREG;
      memcpy (&arg.fpregs, fpregs, sizeof (arg.fpregs));
      win = (write (pi->ctl_fd, (void *) &arg, sizeof (arg)) == sizeof (arg));
    }

  /* Policy: writing the registers invalidates our cache.  */
  pi->fpregs_valid = 0;
  return win;
}

/* Send a signal to the proc or lwp with the semantics of "kill()".
   Returns non-zero for success, zero for failure.  */

static int
proc_kill (procinfo *pi, int signo)
{
  int win;

  /* We might conceivably apply this operation to an LWP, and the
     LWP's ctl file descriptor might not be open.  */

  if (pi->ctl_fd == 0 && open_procinfo_files (pi, FD_CTL) == 0)
    return 0;
  else
    {
      procfs_ctl_t cmd[2];

      cmd[0] = PCKILL;
      cmd[1] = signo;
      win = (write (pi->ctl_fd, (char *) &cmd, sizeof (cmd)) == sizeof (cmd));
  }

  return win;
}

/* Find the pid of the process that started this one.  Returns the
   parent process pid, or zero.  */

static int
proc_parent_pid (procinfo *pi)
{
  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;

  return pi->prstatus.pr_ppid;
}

/* Convert a target address (a.k.a. CORE_ADDR) into a host address
   (a.k.a void pointer)!  */

static void *
procfs_address_to_host_pointer (CORE_ADDR addr)
{
  gdbarch *arch = current_inferior ()->arch ();
  type *ptr_type = builtin_type (arch)->builtin_data_ptr;
  void *ptr;

  gdb_assert (sizeof (ptr) == ptr_type->length ());
  gdbarch_address_to_pointer (arch, ptr_type, (gdb_byte *) &ptr, addr);
  return ptr;
}

static int
proc_set_watchpoint (procinfo *pi, CORE_ADDR addr, int len, int wflags)
{
  struct {
    procfs_ctl_t cmd;
    char watch[sizeof (prwatch_t)];
  } arg;
  prwatch_t pwatch;

  /* NOTE: cagney/2003-02-01: Even more horrible hack.  Need to
     convert a target address into something that can be stored in a
     native data structure.  */
  pwatch.pr_vaddr  = (uintptr_t) procfs_address_to_host_pointer (addr);
  pwatch.pr_size   = len;
  pwatch.pr_wflags = wflags;
  arg.cmd = PCWATCH;
  memcpy (arg.watch, &pwatch, sizeof (prwatch_t));
  return (write (pi->ctl_fd, &arg, sizeof (arg)) == sizeof (arg));
}

/* =============== END, non-thread part of /proc  "MODULE" =============== */

/* =================== Thread "MODULE" =================== */

/* Returns the number of threads for the process.  */

static int
proc_get_nthreads (procinfo *pi)
{
  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;

  /* Only works for the process procinfo, because the LWP procinfos do not
     get prstatus filled in.  */
  if (pi->tid != 0)	/* Find the parent process procinfo.  */
    pi = find_procinfo_or_die (pi->pid, 0);
  return pi->prstatus.pr_nlwp;
}

/* Return the ID of the thread that had an event of interest.
   (ie. the one that hit a breakpoint or other traced event).  All
   other things being equal, this should be the ID of a thread that is
   currently executing.  */

static int
proc_get_current_thread (procinfo *pi)
{
  /* Note: this should be applied to the root procinfo for the
     process, not to the procinfo for an LWP.  If applied to the
     procinfo for an LWP, it will simply return that LWP's ID.  In
     that case, find the parent process procinfo.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  if (!pi->status_valid)
    if (!proc_get_status (pi))
      return 0;

  return pi->prstatus.pr_lwp.pr_lwpid;
}

/* Discover the IDs of all the threads within the process, and create
   a procinfo for each of them (chained to the parent).  Returns
   non-zero for success, zero for failure.  */

static int
proc_delete_dead_threads (procinfo *parent, procinfo *thread, void *ignore)
{
  if (thread && parent)	/* sanity */
    {
      thread->status_valid = 0;
      if (!proc_get_status (thread))
	destroy_one_procinfo (&parent->thread_list, thread);
    }
  return 0;	/* keep iterating */
}

static int
proc_update_threads (procinfo *pi)
{
  char pathname[MAX_PROC_NAME_SIZE + 16];
  struct dirent *direntry;
  procinfo *thread;
  gdb_dir_up dirp;
  int lwpid;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  proc_iterate_over_threads (pi, proc_delete_dead_threads, NULL);

  /* Note: this brute-force method was originally devised for Unixware
     (support removed since), and will also work on Solaris 2.6 and
     2.7.  The original comment mentioned the existence of a much
     simpler and more elegant way to do this on Solaris, but didn't
     point out what that was.  */

  strcpy (pathname, pi->pathname);
  strcat (pathname, "/lwp");
  dirp.reset (opendir (pathname));
  if (dirp == NULL)
    proc_error (pi, "update_threads, opendir", __LINE__);

  while ((direntry = readdir (dirp.get ())) != NULL)
    if (direntry->d_name[0] != '.')		/* skip '.' and '..' */
      {
	lwpid = atoi (&direntry->d_name[0]);
	thread = create_procinfo (pi->pid, lwpid);
	if (thread == NULL)
	  proc_error (pi, "update_threads, create_procinfo", __LINE__);
      }
  pi->threads_valid = 1;
  return 1;
}

/* Given a pointer to a function, call that function once for each lwp
   in the procinfo list, until the function returns non-zero, in which
   event return the value returned by the function.

   Note: this function does NOT call update_threads.  If you want to
   discover new threads first, you must call that function explicitly.
   This function just makes a quick pass over the currently-known
   procinfos.

   PI is the parent process procinfo.  FUNC is the per-thread
   function.  PTR is an opaque parameter for function.  Returns the
   first non-zero return value from the callee, or zero.  */

static int
proc_iterate_over_threads (procinfo *pi,
			   int (*func) (procinfo *, procinfo *, void *),
			   void *ptr)
{
  procinfo *thread, *next;
  int retval = 0;

  /* We should never have to apply this operation to any procinfo
     except the one for the main process.  If that ever changes for
     any reason, then take out the following clause and replace it
     with one that makes sure the ctl_fd is open.  */

  if (pi->tid != 0)
    pi = find_procinfo_or_die (pi->pid, 0);

  for (thread = pi->thread_list; thread != NULL; thread = next)
    {
      next = thread->next;	/* In case thread is destroyed.  */
      retval = (*func) (pi, thread, ptr);
      if (retval != 0)
	break;
    }

  return retval;
}

/* =================== END, Thread "MODULE" =================== */

/* =================== END, /proc  "MODULE" =================== */

/* ===================  GDB  "MODULE" =================== */

/* Here are all of the gdb target vector functions and their
   friends.  */

static void do_attach (ptid_t ptid);
static void do_detach ();
static void proc_trace_syscalls_1 (procinfo *pi, int syscallnum,
				   int entry_or_exit, int mode, int from_tty);

/* Sets up the inferior to be debugged.  Registers to trace signals,
   hardware faults, and syscalls.  Note: does not set RLC flag: caller
   may want to customize that.  Returns zero for success (note!
   unlike most functions in this module); on failure, returns the LINE
   NUMBER where it failed!  */

static int
procfs_debug_inferior (procinfo *pi)
{
  fltset_t traced_faults;
  sigset_t traced_signals;
  sysset_t *traced_syscall_entries;
  sysset_t *traced_syscall_exits;
  int status;

  /* Register to trace hardware faults in the child.  */
  prfillset (&traced_faults);		/* trace all faults...  */
  prdelset  (&traced_faults, FLTPAGE);	/* except page fault.  */
  if (!proc_set_traced_faults  (pi, &traced_faults))
    return __LINE__;

  /* Initially, register to trace all signals in the child.  */
  prfillset (&traced_signals);
  if (!proc_set_traced_signals (pi, &traced_signals))
    return __LINE__;


  /* Register to trace the 'exit' system call (on entry).  */
  traced_syscall_entries = XNEW (sysset_t);
  premptyset (traced_syscall_entries);
  praddset (traced_syscall_entries, SYS_exit);
  praddset (traced_syscall_entries, SYS_lwp_exit);

  status = proc_set_traced_sysentry (pi, traced_syscall_entries);
  xfree (traced_syscall_entries);
  if (!status)
    return __LINE__;

  /* Method for tracing exec syscalls.  */
  traced_syscall_exits = XNEW (sysset_t);
  premptyset (traced_syscall_exits);
  praddset (traced_syscall_exits, SYS_execve);
  praddset (traced_syscall_exits, SYS_lwp_create);
  praddset (traced_syscall_exits, SYS_lwp_exit);

  status = proc_set_traced_sysexit (pi, traced_syscall_exits);
  xfree (traced_syscall_exits);
  if (!status)
    return __LINE__;

  return 0;
}

void
procfs_target::attach (const char *args, int from_tty)
{
  int   pid;

  pid = parse_pid_to_attach (args);

  if (pid == getpid ())
    error (_("Attaching GDB to itself is not a good idea..."));

  /* Push the target if needed, ensure it gets un-pushed it if attach fails.  */
  inferior *inf = current_inferior ();
  target_unpush_up unpusher;
  if (!inf->target_is_pushed (this))
    {
      inf->push_target (this);
      unpusher.reset (this);
    }

  target_announce_attach (from_tty, pid);

  do_attach (ptid_t (pid));

  /* Everything went fine, keep the target pushed.  */
  unpusher.release ();
}

void
procfs_target::detach (inferior *inf, int from_tty)
{
  target_announce_detach (from_tty);

  do_detach ();

  switch_to_no_thread ();
  detach_inferior (inf);
  maybe_unpush_target ();
}

static void
do_attach (ptid_t ptid)
{
  procinfo *pi;
  struct inferior *inf;
  int fail;
  int lwpid;

  pi = create_procinfo (ptid.pid (), 0);
  if (pi == NULL)
    perror (_("procfs: out of memory in 'attach'"));

  if (!open_procinfo_files (pi, FD_CTL))
    {
      int saved_errno = errno;
      std::string errmsg
	= string_printf ("procfs:%d -- do_attach: couldn't open /proc "
			 "file for process %d", __LINE__, ptid.pid ());
      errno = saved_errno;
      dead_procinfo (pi, errmsg.c_str (), NOKILL);
    }

  /* Stop the process (if it isn't already stopped).  */
  if (proc_flags (pi) & (PR_STOPPED | PR_ISTOP))
    {
      pi->was_stopped = 1;
      proc_prettyprint_why (proc_why (pi), proc_what (pi), 1);
    }
  else
    {
      pi->was_stopped = 0;
      /* Set the process to run again when we close it.  */
      if (!proc_set_run_on_last_close (pi))
	dead_procinfo (pi, "do_attach: couldn't set RLC.", NOKILL);

      /* Now stop the process.  */
      if (!proc_stop_process (pi))
	dead_procinfo (pi, "do_attach: couldn't stop the process.", NOKILL);
      pi->ignore_next_sigstop = 1;
    }
  /* Save some of the /proc state to be restored if we detach.  */
  if (!proc_get_traced_faults   (pi, &pi->saved_fltset))
    dead_procinfo (pi, "do_attach: couldn't save traced faults.", NOKILL);
  if (!proc_get_traced_signals  (pi, &pi->saved_sigset))
    dead_procinfo (pi, "do_attach: couldn't save traced signals.", NOKILL);
  if (!proc_get_traced_sysentry (pi, pi->saved_entryset))
    dead_procinfo (pi, "do_attach: couldn't save traced syscall entries.",
		   NOKILL);
  if (!proc_get_traced_sysexit  (pi, pi->saved_exitset))
    dead_procinfo (pi, "do_attach: couldn't save traced syscall exits.",
		   NOKILL);
  if (!proc_get_held_signals    (pi, &pi->saved_sighold))
    dead_procinfo (pi, "do_attach: couldn't save held signals.", NOKILL);

  fail = procfs_debug_inferior (pi);
  if (fail != 0)
    dead_procinfo (pi, "do_attach: failed in procfs_debug_inferior", NOKILL);

  inf = current_inferior ();
  inferior_appeared (inf, pi->pid);
  /* Let GDB know that the inferior was attached.  */
  inf->attach_flag = true;

  /* Create a procinfo for the current lwp.  */
  lwpid = proc_get_current_thread (pi);
  create_procinfo (pi->pid, lwpid);

  /* Add it to gdb's thread list.  */
  ptid = ptid_t (pi->pid, lwpid, 0);
  thread_info *thr = add_thread (&the_procfs_target, ptid);
  switch_to_thread (thr);
}

static void
do_detach ()
{
  procinfo *pi;

  /* Find procinfo for the main process.  */
  pi = find_procinfo_or_die (inferior_ptid.pid (),
			     0); /* FIXME: threads */

  if (!proc_set_traced_signals (pi, &pi->saved_sigset))
    proc_warn (pi, "do_detach, set_traced_signal", __LINE__);

  if (!proc_set_traced_faults (pi, &pi->saved_fltset))
    proc_warn (pi, "do_detach, set_traced_faults", __LINE__);

  if (!proc_set_traced_sysentry (pi, pi->saved_entryset))
    proc_warn (pi, "do_detach, set_traced_sysentry", __LINE__);

  if (!proc_set_traced_sysexit (pi, pi->saved_exitset))
    proc_warn (pi, "do_detach, set_traced_sysexit", __LINE__);

  if (!proc_set_held_signals (pi, &pi->saved_sighold))
    proc_warn (pi, "do_detach, set_held_signals", __LINE__);

  if (proc_flags (pi) & (PR_STOPPED | PR_ISTOP))
    if (!(pi->was_stopped)
	|| query (_("Was stopped when attached, make it runnable again? ")))
      {
	/* Clear any pending signal.  */
	if (!proc_clear_current_fault (pi))
	  proc_warn (pi, "do_detach, clear_current_fault", __LINE__);

	if (!proc_clear_current_signal (pi))
	  proc_warn (pi, "do_detach, clear_current_signal", __LINE__);

	if (!proc_set_run_on_last_close (pi))
	  proc_warn (pi, "do_detach, set_rlc", __LINE__);
      }

  destroy_procinfo (pi);
}

/* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
   for all registers.

   NOTE: Since the /proc interface cannot give us individual
   registers, we pay no attention to REGNUM, and just fetch them all.
   This results in the possibility that we will do unnecessarily many
   fetches, since we may be called repeatedly for individual
   registers.  So we cache the results, and mark the cache invalid
   when the process is resumed.  */

void
procfs_target::fetch_registers (struct regcache *regcache, int regnum)
{
  gdb_gregset_t *gregs;
  procinfo *pi;
  ptid_t ptid = regcache->ptid ();
  int pid = ptid.pid ();
  int tid = ptid.lwp ();
  struct gdbarch *gdbarch = regcache->arch ();

  pi = find_procinfo_or_die (pid, tid);

  if (pi == NULL)
    error (_("procfs: fetch_registers failed to find procinfo for %s"),
	   target_pid_to_str (ptid).c_str ());

  gregs = proc_get_gregs (pi);
  if (gregs == NULL)
    proc_error (pi, "fetch_registers, get_gregs", __LINE__);

  supply_gregset (regcache, (const gdb_gregset_t *) gregs);

  if (gdbarch_fp0_regnum (gdbarch) >= 0) /* Do we have an FPU?  */
    {
      gdb_fpregset_t *fpregs;

      if ((regnum >= 0 && regnum < gdbarch_fp0_regnum (gdbarch))
	  || regnum == gdbarch_pc_regnum (gdbarch)
	  || regnum == gdbarch_sp_regnum (gdbarch))
	return;			/* Not a floating point register.  */

      fpregs = proc_get_fpregs (pi);
      if (fpregs == NULL)
	proc_error (pi, "fetch_registers, get_fpregs", __LINE__);

      supply_fpregset (regcache, (const gdb_fpregset_t *) fpregs);
    }
}

/* Store register REGNUM back into the inferior.  If REGNUM is -1, do
   this for all registers.

   NOTE: Since the /proc interface will not read individual registers,
   we will cache these requests until the process is resumed, and only
   then write them back to the inferior process.

   FIXME: is that a really bad idea?  Have to think about cases where
   writing one register might affect the value of others, etc.  */

void
procfs_target::store_registers (struct regcache *regcache, int regnum)
{
  gdb_gregset_t *gregs;
  procinfo *pi;
  ptid_t ptid = regcache->ptid ();
  int pid = ptid.pid ();
  int tid = ptid.lwp ();
  struct gdbarch *gdbarch = regcache->arch ();

  pi = find_procinfo_or_die (pid, tid);

  if (pi == NULL)
    error (_("procfs: store_registers: failed to find procinfo for %s"),
	   target_pid_to_str (ptid).c_str ());

  gregs = proc_get_gregs (pi);
  if (gregs == NULL)
    proc_error (pi, "store_registers, get_gregs", __LINE__);

  fill_gregset (regcache, gregs, regnum);
  if (!proc_set_gregs (pi))
    proc_error (pi, "store_registers, set_gregs", __LINE__);

  if (gdbarch_fp0_regnum (gdbarch) >= 0) /* Do we have an FPU?  */
    {
      gdb_fpregset_t *fpregs;

      if ((regnum >= 0 && regnum < gdbarch_fp0_regnum (gdbarch))
	  || regnum == gdbarch_pc_regnum (gdbarch)
	  || regnum == gdbarch_sp_regnum (gdbarch))
	return;			/* Not a floating point register.  */

      fpregs = proc_get_fpregs (pi);
      if (fpregs == NULL)
	proc_error (pi, "store_registers, get_fpregs", __LINE__);

      fill_fpregset (regcache, fpregs, regnum);
      if (!proc_set_fpregs (pi))
	proc_error (pi, "store_registers, set_fpregs", __LINE__);
    }
}

/* Retrieve the next stop event from the child process.  If child has
   not stopped yet, wait for it to stop.  Translate /proc eventcodes
   (or possibly wait eventcodes) into gdb internal event codes.
   Returns the id of process (and possibly thread) that incurred the
   event.  Event codes are returned through a pointer parameter.  */

ptid_t
procfs_target::wait (ptid_t ptid, struct target_waitstatus *status,
		     target_wait_flags options)
{
  /* First cut: loosely based on original version 2.1.  */
  procinfo *pi;
  int       wstat;
  int       temp_tid;
  ptid_t    retval, temp_ptid;
  int       why, what, flags;
  int       retry = 0;

wait_again:

  retry++;
  wstat    = 0;
  retval   = ptid_t (-1);

  /* Find procinfo for main process.  */

  /* procfs_target currently only supports one inferior.  */
  inferior *inf = current_inferior ();

  pi = find_procinfo_or_die (inf->pid, 0);
  if (pi)
    {
      /* We must assume that the status is stale now...  */
      pi->status_valid = 0;
      pi->gregs_valid  = 0;
      pi->fpregs_valid = 0;

#if 0	/* just try this out...  */
      flags = proc_flags (pi);
      why   = proc_why (pi);
      if ((flags & PR_STOPPED) && (why == PR_REQUESTED))
	pi->status_valid = 0;	/* re-read again, IMMEDIATELY...  */
#endif
      /* If child is not stopped, wait for it to stop.  */
      if (!(proc_flags (pi) & (PR_STOPPED | PR_ISTOP))
	  && !proc_wait_for_stop (pi))
	{
	  /* wait_for_stop failed: has the child terminated?  */
	  if (errno == ENOENT)
	    {
	      int wait_retval;

	      /* /proc file not found; presumably child has terminated.  */
	      wait_retval = ::wait (&wstat); /* "wait" for the child's exit.  */

	      /* Wrong child?  */
	      if (wait_retval != inf->pid)
		error (_("procfs: couldn't stop "
			 "process %d: wait returned %d."),
		       inf->pid, wait_retval);
	      /* FIXME: might I not just use waitpid?
		 Or try find_procinfo to see if I know about this child?  */
	      retval = ptid_t (wait_retval);
	    }
	  else if (errno == EINTR)
	    goto wait_again;
	  else
	    {
	      /* Unknown error from wait_for_stop.  */
	      proc_error (pi, "target_wait (wait_for_stop)", __LINE__);
	    }
	}
      else
	{
	  /* This long block is reached if either:
	     a) the child was already stopped, or
	     b) we successfully waited for the child with wait_for_stop.
	     This block will analyze the /proc status, and translate it
	     into a waitstatus for GDB.

	     If we actually had to call wait because the /proc file
	     is gone (child terminated), then we skip this block,
	     because we already have a waitstatus.  */

	  flags = proc_flags (pi);
	  why   = proc_why (pi);
	  what  = proc_what (pi);

	  if (flags & (PR_STOPPED | PR_ISTOP))
	    {
	      /* If it's running async (for single_thread control),
		 set it back to normal again.  */
	      if (flags & PR_ASYNC)
		if (!proc_unset_async (pi))
		  proc_error (pi, "target_wait, unset_async", __LINE__);

	      if (info_verbose)
		proc_prettyprint_why (why, what, 1);

	      /* The 'pid' we will return to GDB is composed of
		 the process ID plus the lwp ID.  */
	      retval = ptid_t (pi->pid, proc_get_current_thread (pi), 0);

	      switch (why) {
	      case PR_SIGNALLED:
		wstat = (what << 8) | 0177;
		break;
	      case PR_SYSENTRY:
		if (what == SYS_lwp_exit)
		  {
		    delete_thread (this->find_thread (retval));
		    proc_resume (pi, ptid, 0, GDB_SIGNAL_0);
		    goto wait_again;
		  }
		else if (what == SYS_exit)
		  {
		    /* Handle SYS_exit call only.  */
		    /* Stopped at entry to SYS_exit.
		       Make it runnable, resume it, then use
		       the wait system call to get its exit code.
		       Proc_run_process always clears the current
		       fault and signal.
		       Then return its exit status.  */
		    pi->status_valid = 0;
		    wstat = 0;
		    /* FIXME: what we should do is return
		       TARGET_WAITKIND_SPURIOUS.  */
		    if (!proc_run_process (pi, 0, 0))
		      proc_error (pi, "target_wait, run_process", __LINE__);

		    if (inf->attach_flag)
		      {
			/* Don't call wait: simulate waiting for exit,
			   return a "success" exit code.  Bogus: what if
			   it returns something else?  */
			wstat = 0;
			retval = ptid_t (inf->pid);  /* ? ? ? */
		      }
		    else
		      {
			int temp = ::wait (&wstat);

			/* FIXME: shouldn't I make sure I get the right
			   event from the right process?  If (for
			   instance) I have killed an earlier inferior
			   process but failed to clean up after it
			   somehow, I could get its termination event
			   here.  */

			/* If wait returns -1, that's what we return
			   to GDB.  */
			if (temp < 0)
			  retval = ptid_t (temp);
		      }
		  }
		else
		  {
		    gdb_printf (_("procfs: trapped on entry to "));
		    proc_prettyprint_syscall (proc_what (pi), 0);
		    gdb_printf ("\n");

		    long i, nsysargs, *sysargs;

		    nsysargs = proc_nsysarg (pi);
		    sysargs  = proc_sysargs (pi);

		    if (nsysargs > 0 && sysargs != NULL)
		      {
			gdb_printf (_("%ld syscall arguments:\n"),
				    nsysargs);
			for (i = 0; i < nsysargs; i++)
			  gdb_printf ("#%ld: 0x%08lx\n",
				      i, sysargs[i]);
		      }

		    proc_resume (pi, ptid, 0, GDB_SIGNAL_0);
		    goto wait_again;
		  }
		break;
	      case PR_SYSEXIT:
		if (what == SYS_execve)
		  {
		    /* Hopefully this is our own "fork-child" execing
		       the real child.  Hoax this event into a trap, and
		       GDB will see the child about to execute its start
		       address.  */
		    wstat = (SIGTRAP << 8) | 0177;
		  }
		else if (what == SYS_lwp_create)
		  {
		    /* This syscall is somewhat like fork/exec.  We
		       will get the event twice: once for the parent
		       LWP, and once for the child.  We should already
		       know about the parent LWP, but the child will
		       be new to us.  So, whenever we get this event,
		       if it represents a new thread, simply add the
		       thread to the list.  */

		    /* If not in procinfo list, add it.  */
		    temp_tid = proc_get_current_thread (pi);
		    if (!find_procinfo (pi->pid, temp_tid))
		      create_procinfo  (pi->pid, temp_tid);

		    temp_ptid = ptid_t (pi->pid, temp_tid, 0);
		    /* If not in GDB's thread list, add it.  */
		    if (!in_thread_list (this, temp_ptid))
		      add_thread (this, temp_ptid);

		    proc_resume (pi, ptid, 0, GDB_SIGNAL_0);
		    goto wait_again;
		  }
		else if (what == SYS_lwp_exit)
		  {
		    delete_thread (this->find_thread (retval));
		    status->set_spurious ();
		    return retval;
		  }
		else
		  {
		    gdb_printf (_("procfs: trapped on exit from "));
		    proc_prettyprint_syscall (proc_what (pi), 0);
		    gdb_printf ("\n");

		    long i, nsysargs, *sysargs;

		    nsysargs = proc_nsysarg (pi);
		    sysargs = proc_sysargs (pi);

		    if (nsysargs > 0 && sysargs != NULL)
		      {
			gdb_printf (_("%ld syscall arguments:\n"),
				    nsysargs);
			for (i = 0; i < nsysargs; i++)
			  gdb_printf ("#%ld: 0x%08lx\n",
				      i, sysargs[i]);
		      }

		    proc_resume (pi, ptid, 0, GDB_SIGNAL_0);
		    goto wait_again;
		  }
		break;
	      case PR_REQUESTED:
#if 0	/* FIXME */
		wstat = (SIGSTOP << 8) | 0177;
		break;
#else
		if (retry < 5)
		  {
		    gdb_printf (_("Retry #%d:\n"), retry);
		    pi->status_valid = 0;
		    goto wait_again;
		  }
		else
		  {
		    /* If not in procinfo list, add it.  */
		    temp_tid = proc_get_current_thread (pi);
		    if (!find_procinfo (pi->pid, temp_tid))
		      create_procinfo  (pi->pid, temp_tid);

		    /* If not in GDB's thread list, add it.  */
		    temp_ptid = ptid_t (pi->pid, temp_tid, 0);
		    if (!in_thread_list (this, temp_ptid))
		      add_thread (this, temp_ptid);

		    status->set_stopped (GDB_SIGNAL_0);
		    return retval;
		  }
#endif
	      case PR_JOBCONTROL:
		wstat = (what << 8) | 0177;
		break;
	      case PR_FAULTED:
		{
		  int signo = pi->prstatus.pr_lwp.pr_info.si_signo;
		  if (signo != 0)
		    wstat = (signo << 8) | 0177;
		}
		break;
	      default:	/* switch (why) unmatched */
		gdb_printf ("procfs:%d -- ", __LINE__);
		gdb_printf (_("child stopped for unknown reason:\n"));
		proc_prettyprint_why (why, what, 1);
		error (_("... giving up..."));
		break;
	      }
	      /* Got this far without error: If retval isn't in the
		 threads database, add it.  */
	      if (retval.pid () > 0
		  && !in_thread_list (this, retval))
		{
		  /* We have a new thread.  We need to add it both to
		     GDB's list and to our own.  If we don't create a
		     procinfo, resume may be unhappy later.  */
		  add_thread (this, retval);
		  if (find_procinfo (retval.pid (),
				     retval.lwp ()) == NULL)
		    create_procinfo (retval.pid (),
				     retval.lwp ());
		}
	    }
	  else	/* Flags do not indicate STOPPED.  */
	    {
	      /* surely this can't happen...  */
	      gdb_printf ("procfs:%d -- process not stopped.\n",
			  __LINE__);
	      proc_prettyprint_flags (flags, 1);
	      error (_("procfs: ...giving up..."));
	    }
	}

      if (status)
	*status = host_status_to_waitstatus (wstat);
    }

  return retval;
}

/* Perform a partial transfer to/from the specified object.  For
   memory transfers, fall back to the old memory xfer functions.  */

enum target_xfer_status
procfs_target::xfer_partial (enum target_object object,
			     const char *annex, gdb_byte *readbuf,
			     const gdb_byte *writebuf, ULONGEST offset,
			     ULONGEST len, ULONGEST *xfered_len)
{
  switch (object)
    {
    case TARGET_OBJECT_MEMORY:
      return procfs_xfer_memory (readbuf, writebuf, offset, len, xfered_len);

    case TARGET_OBJECT_AUXV:
      return memory_xfer_auxv (this, object, annex, readbuf, writebuf,
			       offset, len, xfered_len);

    default:
      return this->beneath ()->xfer_partial (object, annex,
					     readbuf, writebuf, offset, len,
					     xfered_len);
    }
}

/* Helper for procfs_xfer_partial that handles memory transfers.
   Arguments are like target_xfer_partial.  */

static enum target_xfer_status
procfs_xfer_memory (gdb_byte *readbuf, const gdb_byte *writebuf,
		    ULONGEST memaddr, ULONGEST len, ULONGEST *xfered_len)
{
  procinfo *pi;
  int nbytes;

  /* Find procinfo for main process.  */
  pi = find_procinfo_or_die (inferior_ptid.pid (), 0);
  if (pi->as_fd == 0 && open_procinfo_files (pi, FD_AS) == 0)
    {
      proc_warn (pi, "xfer_memory, open_proc_files", __LINE__);
      return TARGET_XFER_E_IO;
    }

  if (lseek (pi->as_fd, (off_t) memaddr, SEEK_SET) != (off_t) memaddr)
    return TARGET_XFER_E_IO;

  if (writebuf != NULL)
    {
      PROCFS_NOTE ("write memory:\n");
      nbytes = write (pi->as_fd, writebuf, len);
    }
  else
    {
      PROCFS_NOTE ("read  memory:\n");
      nbytes = read (pi->as_fd, readbuf, len);
    }
  if (nbytes <= 0)
    return TARGET_XFER_E_IO;
  *xfered_len = nbytes;
  return TARGET_XFER_OK;
}

/* Called by target_resume before making child runnable.  Mark cached
   registers and status's invalid.  If there are "dirty" caches that
   need to be written back to the child process, do that.

   File descriptors are also cached.  As they are a limited resource,
   we cannot hold onto them indefinitely.  However, as they are
   expensive to open, we don't want to throw them away
   indiscriminately either.  As a compromise, we will keep the file
   descriptors for the parent process, but discard any file
   descriptors we may have accumulated for the threads.

   As this function is called by iterate_over_threads, it always
   returns zero (so that iterate_over_threads will keep
   iterating).  */

static int
invalidate_cache (procinfo *parent, procinfo *pi, void *ptr)
{
  /* About to run the child; invalidate caches and do any other
     cleanup.  */

  if (parent != NULL)
    {
      /* The presence of a parent indicates that this is an LWP.
	 Close any file descriptors that it might have open.
	 We don't do this to the master (parent) procinfo.  */

      close_procinfo_files (pi);
    }
  pi->gregs_valid   = 0;
  pi->fpregs_valid  = 0;
  pi->status_valid  = 0;
  pi->threads_valid = 0;

  return 0;
}

/* Make child process PI runnable.

   If STEP is true, then arrange for the child to stop again after
   executing a single instruction.  SCOPE_PTID, STEP and SIGNO are
   like in the target_resume interface.  */

static void
proc_resume (procinfo *pi, ptid_t scope_ptid, int step, enum gdb_signal signo)
{
  procinfo *thread;
  int native_signo;

  /* FIXME: Check/reword.  */

  /* prrun.prflags |= PRCFAULT;    clear current fault.
     PRCFAULT may be replaced by a PCCFAULT call (proc_clear_current_fault)
     This basically leaves PRSTEP and PRCSIG.
     PRCSIG is like PCSSIG (proc_clear_current_signal).
     So basically PR_STEP is the sole argument that must be passed
     to proc_run_process.  */

  errno = 0;

  /* Convert signal to host numbering.  */
  if (signo == 0 || (signo == GDB_SIGNAL_STOP && pi->ignore_next_sigstop))
    native_signo = 0;
  else
    native_signo = gdb_signal_to_host (signo);

  pi->ignore_next_sigstop = 0;

  /* Running the process voids all cached registers and status.  */
  /* Void the threads' caches first.  */
  proc_iterate_over_threads (pi, invalidate_cache, NULL);
  /* Void the process procinfo's caches.  */
  invalidate_cache (NULL, pi, NULL);

  if (scope_ptid.pid () != -1)
    {
      /* Resume a specific thread, presumably suppressing the
	 others.  */
      thread = find_procinfo (scope_ptid.pid (), scope_ptid.lwp ());
      if (thread != NULL)
	{
	  if (thread->tid != 0)
	    {
	      /* We're to resume a specific thread, and not the
		 others.  Set the child process's PR_ASYNC flag.  */
	      if (!proc_set_async (pi))
		proc_error (pi, "target_resume, set_async", __LINE__);
	      pi = thread;	/* Substitute the thread's procinfo
				   for run.  */
	    }
	}
    }

  if (!proc_run_process (pi, step, native_signo))
    {
      if (errno == EBUSY)
	warning (_("resume: target already running.  "
		   "Pretend to resume, and hope for the best!"));
      else
	proc_error (pi, "target_resume", __LINE__);
    }
}

/* Implementation of target_ops::resume.  */

void
procfs_target::resume (ptid_t scope_ptid, int step, enum gdb_signal signo)
{
  /* Find procinfo for main process.  */
  procinfo *pi = find_procinfo_or_die (inferior_ptid.pid (), 0);

  proc_resume (pi, scope_ptid, step, signo);
}

/* Set up to trace signals in the child process.  */

void
procfs_target::pass_signals (gdb::array_view<const unsigned char> pass_signals)
{
  sigset_t signals;
  procinfo *pi = find_procinfo_or_die (inferior_ptid.pid (), 0);
  int signo;

  prfillset (&signals);

  for (signo = 0; signo < NSIG; signo++)
    {
      int target_signo = gdb_signal_from_host (signo);
      if (target_signo < pass_signals.size () && pass_signals[target_signo])
	prdelset (&signals, signo);
    }

  if (!proc_set_traced_signals (pi, &signals))
    proc_error (pi, "pass_signals", __LINE__);
}

/* Print status information about the child process.  */

void
procfs_target::files_info ()
{
  struct inferior *inf = current_inferior ();

  gdb_printf (_("\tUsing the running image of %s %s via /proc.\n"),
	      inf->attach_flag? "attached": "child",
	      target_pid_to_str (ptid_t (inf->pid)).c_str ());
}

/* Make it die.  Wait for it to die.  Clean up after it.  Note: this
   should only be applied to the real process, not to an LWP, because
   of the check for parent-process.  If we need this to work for an
   LWP, it needs some more logic.  */

static void
unconditionally_kill_inferior (procinfo *pi)
{
  int parent_pid;

  parent_pid = proc_parent_pid (pi);
  if (!proc_kill (pi, SIGKILL))
    proc_error (pi, "unconditionally_kill, proc_kill", __LINE__);
  destroy_procinfo (pi);

  /* If pi is GDB's child, wait for it to die.  */
  if (parent_pid == getpid ())
    /* FIXME: should we use waitpid to make sure we get the right event?
       Should we check the returned event?  */
    {
#if 0
      int status, ret;

      ret = waitpid (pi->pid, &status, 0);
#else
      wait (NULL);
#endif
    }
}

/* We're done debugging it, and we want it to go away.  Then we want
   GDB to forget all about it.  */

void
procfs_target::kill ()
{
  if (inferior_ptid != null_ptid) /* ? */
    {
      /* Find procinfo for main process.  */
      procinfo *pi = find_procinfo (inferior_ptid.pid (), 0);

      if (pi)
	unconditionally_kill_inferior (pi);
      target_mourn_inferior (inferior_ptid);
    }
}

/* Forget we ever debugged this thing!  */

void
procfs_target::mourn_inferior ()
{
  procinfo *pi;

  if (inferior_ptid != null_ptid)
    {
      /* Find procinfo for main process.  */
      pi = find_procinfo (inferior_ptid.pid (), 0);
      if (pi)
	destroy_procinfo (pi);
    }

  generic_mourn_inferior ();

  maybe_unpush_target ();
}

/* When GDB forks to create a runnable inferior process, this function
   is called on the parent side of the fork.  It's job is to do
   whatever is necessary to make the child ready to be debugged, and
   then wait for the child to synchronize.  */

void
procfs_target::procfs_init_inferior (int pid)
{
  procinfo *pi;
  int fail;
  int lwpid;

  pi = create_procinfo (pid, 0);
  if (pi == NULL)
    perror (_("procfs: out of memory in 'init_inferior'"));

  if (!open_procinfo_files (pi, FD_CTL))
    proc_error (pi, "init_inferior, open_proc_files", __LINE__);

  /*
    xmalloc			// done
    open_procinfo_files		// done
    link list			// done
    prfillset (trace)
    procfs_notice_signals
    prfillset (fault)
    prdelset (FLTPAGE)
    */

  /* If not stopped yet, wait for it to stop.  */
  if (!(proc_flags (pi) & PR_STOPPED) && !(proc_wait_for_stop (pi)))
    dead_procinfo (pi, "init_inferior: wait_for_stop failed", KILL);

  /* Save some of the /proc state to be restored if we detach.  */
  /* FIXME: Why?  In case another debugger was debugging it?
     We're it's parent, for Ghu's sake!  */
  if (!proc_get_traced_signals  (pi, &pi->saved_sigset))
    proc_error (pi, "init_inferior, get_traced_signals", __LINE__);
  if (!proc_get_held_signals    (pi, &pi->saved_sighold))
    proc_error (pi, "init_inferior, get_held_signals", __LINE__);
  if (!proc_get_traced_faults   (pi, &pi->saved_fltset))
    proc_error (pi, "init_inferior, get_traced_faults", __LINE__);
  if (!proc_get_traced_sysentry (pi, pi->saved_entryset))
    proc_error (pi, "init_inferior, get_traced_sysentry", __LINE__);
  if (!proc_get_traced_sysexit  (pi, pi->saved_exitset))
    proc_error (pi, "init_inferior, get_traced_sysexit", __LINE__);

  fail = procfs_debug_inferior (pi);
  if (fail != 0)
    proc_error (pi, "init_inferior (procfs_debug_inferior)", fail);

  /* FIXME: logically, we should really be turning OFF run-on-last-close,
     and possibly even turning ON kill-on-last-close at this point.  But
     I can't make that change without careful testing which I don't have
     time to do right now...  */
  /* Turn on run-on-last-close flag so that the child
     will die if GDB goes away for some reason.  */
  if (!proc_set_run_on_last_close (pi))
    proc_error (pi, "init_inferior, set_RLC", __LINE__);

  /* We now have have access to the lwpid of the main thread/lwp.  */
  lwpid = proc_get_current_thread (pi);

  /* Create a procinfo for the main lwp.  */
  create_procinfo (pid, lwpid);

  /* We already have a main thread registered in the thread table at
     this point, but it didn't have any lwp info yet.  Notify the core
     about it.  This changes inferior_ptid as well.  */
  thread_change_ptid (this, ptid_t (pid), ptid_t (pid, lwpid, 0));

  gdb_startup_inferior (pid, START_INFERIOR_TRAPS_EXPECTED);
}

/* When GDB forks to create a new process, this function is called on
   the child side of the fork before GDB exec's the user program.  Its
   job is to make the child minimally debuggable, so that the parent
   GDB process can connect to the child and take over.  This function
   should do only the minimum to make that possible, and to
   synchronize with the parent process.  The parent process should
   take care of the details.  */

static void
procfs_set_exec_trap (void)
{
  /* This routine called on the child side (inferior side)
     after GDB forks the inferior.  It must use only local variables,
     because it may be sharing data space with its parent.  */

  procinfo *pi;
  sysset_t *exitset;

  pi = create_procinfo (getpid (), 0);
  if (pi == NULL)
    perror_with_name (_("procfs: create_procinfo failed in child"));

  if (open_procinfo_files (pi, FD_CTL) == 0)
    {
      proc_warn (pi, "set_exec_trap, open_proc_files", __LINE__);
      gdb_flush (gdb_stderr);
      /* No need to call "dead_procinfo", because we're going to
	 exit.  */
      _exit (127);
    }

  exitset = XNEW (sysset_t);
  premptyset (exitset);
  praddset (exitset, SYS_execve);

  if (!proc_set_traced_sysexit (pi, exitset))
    {
      proc_warn (pi, "set_exec_trap, set_traced_sysexit", __LINE__);
      gdb_flush (gdb_stderr);
      _exit (127);
    }

  /* FIXME: should this be done in the parent instead?  */
  /* Turn off inherit on fork flag so that all grand-children
     of gdb start with tracing flags cleared.  */
  if (!proc_unset_inherit_on_fork (pi))
    proc_warn (pi, "set_exec_trap, unset_inherit", __LINE__);

  /* Turn off run on last close flag, so that the child process
     cannot run away just because we close our handle on it.
     We want it to wait for the parent to attach.  */
  if (!proc_unset_run_on_last_close (pi))
    proc_warn (pi, "set_exec_trap, unset_RLC", __LINE__);

  /* FIXME: No need to destroy the procinfo --
     we have our own address space, and we're about to do an exec!  */
  /*destroy_procinfo (pi);*/
}

/* Dummy function to be sure fork_inferior uses fork(2) and not vfork(2).
   This avoids a possible deadlock gdb and its vfork'ed child.  */
static void
procfs_pre_trace (void)
{
}

/* This function is called BEFORE gdb forks the inferior process.  Its
   only real responsibility is to set things up for the fork, and tell
   GDB which two functions to call after the fork (one for the parent,
   and one for the child).

   This function does a complicated search for a unix shell program,
   which it then uses to parse arguments and environment variables to
   be sent to the child.  I wonder whether this code could not be
   abstracted out and shared with other unix targets such as
   inf-ptrace?  */

void
procfs_target::create_inferior (const char *exec_file,
				const std::string &allargs,
				char **env, int from_tty)
{
  const char *shell_file = get_shell ();
  char *tryname;
  int pid;

  if (strchr (shell_file, '/') == NULL)
    {

      /* We will be looking down the PATH to find shell_file.  If we
	 just do this the normal way (via execlp, which operates by
	 attempting an exec for each element of the PATH until it
	 finds one which succeeds), then there will be an exec for
	 each failed attempt, each of which will cause a PR_SYSEXIT
	 stop, and we won't know how to distinguish the PR_SYSEXIT's
	 for these failed execs with the ones for successful execs
	 (whether the exec has succeeded is stored at that time in the
	 carry bit or some such architecture-specific and
	 non-ABI-specified place).

	 So I can't think of anything better than to search the PATH
	 now.  This has several disadvantages: (1) There is a race
	 condition; if we find a file now and it is deleted before we
	 exec it, we lose, even if the deletion leaves a valid file
	 further down in the PATH, (2) there is no way to know exactly
	 what an executable (in the sense of "capable of being
	 exec'd") file is.  Using access() loses because it may lose
	 if the caller is the superuser; failing to use it loses if
	 there are ACLs or some such.  */

      const char *p;
      const char *p1;
      /* FIXME-maybe: might want "set path" command so user can change what
	 path is used from within GDB.  */
      const char *path = getenv ("PATH");
      int len;
      struct stat statbuf;

      if (path == NULL)
	path = "/bin:/usr/bin";

      tryname = (char *) alloca (strlen (path) + strlen (shell_file) + 2);
      for (p = path; p != NULL; p = p1 ? p1 + 1: NULL)
	{
	  p1 = strchr (p, ':');
	  if (p1 != NULL)
	    len = p1 - p;
	  else
	    len = strlen (p);
	  memcpy (tryname, p, len);
	  tryname[len] = '\0';
	  strcat (tryname, "/");
	  strcat (tryname, shell_file);
	  if (access (tryname, X_OK) < 0)
	    continue;
	  if (stat (tryname, &statbuf) < 0)
	    continue;
	  if (!S_ISREG (statbuf.st_mode))
	    /* We certainly need to reject directories.  I'm not quite
	       as sure about FIFOs, sockets, etc., but I kind of doubt
	       that people want to exec() these things.  */
	    continue;
	  break;
	}
      if (p == NULL)
	/* Not found.  This must be an error rather than merely passing
	   the file to execlp(), because execlp() would try all the
	   exec()s, causing GDB to get confused.  */
	error (_("procfs:%d -- Can't find shell %s in PATH"),
	       __LINE__, shell_file);

      shell_file = tryname;
    }

  inferior *inf = current_inferior ();
  if (!inf->target_is_pushed (this))
    inf->push_target (this);

  pid = fork_inferior (exec_file, allargs, env, procfs_set_exec_trap,
		       NULL, procfs_pre_trace, shell_file, NULL);

  /* We have something that executes now.  We'll be running through
     the shell at this point (if startup-with-shell is true), but the
     pid shouldn't change.  */
  thread_info *thr = add_thread_silent (this, ptid_t (pid));
  switch_to_thread (thr);

  procfs_init_inferior (pid);
}

/* Callback for update_thread_list.  Calls "add_thread".  */

static int
procfs_notice_thread (procinfo *pi, procinfo *thread, void *ptr)
{
  ptid_t gdb_threadid = ptid_t (pi->pid, thread->tid, 0);

  thread_info *thr = the_procfs_target.find_thread (gdb_threadid);
  if (thr == NULL || thr->state == THREAD_EXITED)
    add_thread (&the_procfs_target, gdb_threadid);

  return 0;
}

/* Query all the threads that the target knows about, and give them
   back to GDB to add to its list.  */

void
procfs_target::update_thread_list ()
{
  procinfo *pi;

  prune_threads ();

  /* Find procinfo for main process.  */
  pi = find_procinfo_or_die (inferior_ptid.pid (), 0);
  proc_update_threads (pi);
  proc_iterate_over_threads (pi, procfs_notice_thread, NULL);
}

/* Return true if the thread is still 'alive'.  This guy doesn't
   really seem to be doing his job.  Got to investigate how to tell
   when a thread is really gone.  */

bool
procfs_target::thread_alive (ptid_t ptid)
{
  int proc, thread;
  procinfo *pi;

  proc    = ptid.pid ();
  thread  = ptid.lwp ();
  /* If I don't know it, it ain't alive!  */
  pi = find_procinfo (proc, thread);
  if (pi == NULL)
    return false;

  /* If I can't get its status, it ain't alive!
     What's more, I need to forget about it!  */
  if (!proc_get_status (pi))
    {
      destroy_procinfo (pi);
      return false;
    }
  /* I couldn't have got its status if it weren't alive, so it's
     alive.  */
  return true;
}

/* Convert PTID to a string.  */

std::string
procfs_target::pid_to_str (ptid_t ptid)
{
  if (ptid.lwp () == 0)
    return string_printf ("process %d", ptid.pid ());
  else
    return string_printf ("LWP %ld", ptid.lwp ());
}

/* Accepts an integer PID; Returns a string representing a file that
   can be opened to get the symbols for the child process.  */

const char *
procfs_target::pid_to_exec_file (int pid)
{
  static char buf[PATH_MAX];
  char name[PATH_MAX];

  /* Solaris 11 introduced /proc/<proc-id>/execname.  */
  xsnprintf (name, sizeof (name), "/proc/%d/execname", pid);
  scoped_fd fd (gdb_open_cloexec (name, O_RDONLY, 0));
  if (fd.get () < 0 || read (fd.get (), buf, PATH_MAX - 1) < 0)
    {
      /* If that fails, fall back to /proc/<proc-id>/path/a.out introduced in
	 Solaris 10.  */
      ssize_t len;

      xsnprintf (name, sizeof (name), "/proc/%d/path/a.out", pid);
      len = readlink (name, buf, PATH_MAX - 1);
      if (len <= 0)
	strcpy (buf, name);
      else
	buf[len] = '\0';
    }

  return buf;
}

/* Insert a watchpoint.  */

static int
procfs_set_watchpoint (ptid_t ptid, CORE_ADDR addr, int len, int rwflag,
		       int after)
{
  int       pflags = 0;
  procinfo *pi;

  pi = find_procinfo_or_die (ptid.pid () == -1 ?
			     inferior_ptid.pid () : ptid.pid (),
			     0);

  /* Translate from GDB's flags to /proc's.  */
  if (len > 0)	/* len == 0 means delete watchpoint.  */
    {
      switch (rwflag) {		/* FIXME: need an enum!  */
      case hw_write:		/* default watchpoint (write) */
	pflags = WA_WRITE;
	break;
      case hw_read:		/* read watchpoint */
	pflags = WA_READ;
	break;
      case hw_access:		/* access watchpoint */
	pflags = WA_READ | WA_WRITE;
	break;
      case hw_execute:		/* execution HW breakpoint */
	pflags = WA_EXEC;
	break;
      default:			/* Something weird.  Return error.  */
	return -1;
      }
      if (after)		/* Stop after r/w access is completed.  */
	pflags |= WA_TRAPAFTER;
    }

  if (!proc_set_watchpoint (pi, addr, len, pflags))
    {
      if (errno == E2BIG)	/* Typical error for no resources.  */
	return -1;		/* fail */
      /* GDB may try to remove the same watchpoint twice.
	 If a remove request returns no match, don't error.  */
      if (errno == ESRCH && len == 0)
	return 0;		/* ignore */
      proc_error (pi, "set_watchpoint", __LINE__);
    }
  return 0;
}

/* Return non-zero if we can set a hardware watchpoint of type TYPE.  TYPE
   is one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint,
   or bp_hardware_watchpoint.  CNT is the number of watchpoints used so
   far.  */

int
procfs_target::can_use_hw_breakpoint (enum bptype type, int cnt, int othertype)
{
  /* Due to the way that proc_set_watchpoint() is implemented, host
     and target pointers must be of the same size.  If they are not,
     we can't use hardware watchpoints.  This limitation is due to the
     fact that proc_set_watchpoint() calls
     procfs_address_to_host_pointer(); a close inspection of
     procfs_address_to_host_pointer will reveal that an internal error
     will be generated when the host and target pointer sizes are
     different.  */
  struct type *ptr_type
    = builtin_type (current_inferior ()->arch ())->builtin_data_ptr;

  if (sizeof (void *) != ptr_type->length ())
    return 0;

  /* Other tests here???  */

  return 1;
}

/* Returns non-zero if process is stopped on a hardware watchpoint
   fault, else returns zero.  */

bool
procfs_target::stopped_by_watchpoint ()
{
  procinfo *pi;

  pi = find_procinfo_or_die (inferior_ptid.pid (), 0);

  if (proc_flags (pi) & (PR_STOPPED | PR_ISTOP))
    if (proc_why (pi) == PR_FAULTED)
      if (proc_what (pi) == FLTWATCH)
	return true;
  return false;
}

/* Returns 1 if the OS knows the position of the triggered watchpoint,
   and sets *ADDR to that address.  Returns 0 if OS cannot report that
   address.  This function is only called if
   procfs_stopped_by_watchpoint returned 1, thus no further checks are
   done.  The function also assumes that ADDR is not NULL.  */

bool
procfs_target::stopped_data_address (CORE_ADDR *addr)
{
  procinfo *pi;

  pi = find_procinfo_or_die (inferior_ptid.pid (), 0);
  return proc_watchpoint_address (pi, addr);
}

int
procfs_target::insert_watchpoint (CORE_ADDR addr, int len,
				  enum target_hw_bp_type type,
				  struct expression *cond)
{
  if (!target_have_steppable_watchpoint ()
      && !gdbarch_have_nonsteppable_watchpoint (current_inferior ()->arch ()))
    /* When a hardware watchpoint fires off the PC will be left at
       the instruction following the one which caused the
       watchpoint.  It will *NOT* be necessary for GDB to step over
       the watchpoint.  */
    return procfs_set_watchpoint (inferior_ptid, addr, len, type, 1);
  else
    /* When a hardware watchpoint fires off the PC will be left at
       the instruction which caused the watchpoint.  It will be
       necessary for GDB to step over the watchpoint.  */
    return procfs_set_watchpoint (inferior_ptid, addr, len, type, 0);
}

int
procfs_target::remove_watchpoint (CORE_ADDR addr, int len,
				  enum target_hw_bp_type type,
				  struct expression *cond)
{
  return procfs_set_watchpoint (inferior_ptid, addr, 0, 0, 0);
}

int
procfs_target::region_ok_for_hw_watchpoint (CORE_ADDR addr, int len)
{
  /* The man page for proc(4) on Solaris 2.6 and up says that the
     system can support "thousands" of hardware watchpoints, but gives
     no method for finding out how many; It doesn't say anything about
     the allowed size for the watched area either.  So we just tell
     GDB 'yes'.  */
  return 1;
}

/* Memory Mappings Functions: */

/* Call a callback function once for each mapping, passing it the
   mapping, an optional secondary callback function, and some optional
   opaque data.  Quit and return the first non-zero value returned
   from the callback.

   PI is the procinfo struct for the process to be mapped.  FUNC is
   the callback function to be called by this iterator.  DATA is the
   optional opaque data to be passed to the callback function.
   CHILD_FUNC is the optional secondary function pointer to be passed
   to the child function.  Returns the first non-zero return value
   from the callback function, or zero.  */

static int
iterate_over_mappings (procinfo *pi, find_memory_region_ftype child_func,
		       void *data,
		       int (*func) (struct prmap *map,
				    find_memory_region_ftype child_func,
				    void *data))
{
  char pathname[MAX_PROC_NAME_SIZE];
  struct prmap *prmaps;
  struct prmap *prmap;
  int funcstat;
  int nmap;
  struct stat sbuf;

  /* Get the number of mappings, allocate space,
     and read the mappings into prmaps.  */
  /* Open map fd.  */
  xsnprintf (pathname, sizeof (pathname), "/proc/%d/map", pi->pid);

  scoped_fd map_fd (open (pathname, O_RDONLY));
  if (map_fd.get () < 0)
    proc_error (pi, "iterate_over_mappings (open)", __LINE__);

  /* Use stat to determine the file size, and compute
     the number of prmap_t objects it contains.  */
  if (fstat (map_fd.get (), &sbuf) != 0)
    proc_error (pi, "iterate_over_mappings (fstat)", __LINE__);

  nmap = sbuf.st_size / sizeof (prmap_t);
  prmaps = (struct prmap *) alloca ((nmap + 1) * sizeof (*prmaps));
  if (read (map_fd.get (), (char *) prmaps, nmap * sizeof (*prmaps))
      != (nmap * sizeof (*prmaps)))
    proc_error (pi, "iterate_over_mappings (read)", __LINE__);

  for (prmap = prmaps; nmap > 0; prmap++, nmap--)
    {
      funcstat = (*func) (prmap, child_func, data);
      if (funcstat != 0)
	return funcstat;
    }

  return 0;
}

/* Implements the to_find_memory_regions method.  Calls an external
   function for each memory region.
   Returns the integer value returned by the callback.  */

static int
find_memory_regions_callback (struct prmap *map,
			      find_memory_region_ftype func, void *data)
{
  return (*func) ((CORE_ADDR) map->pr_vaddr,
		  map->pr_size,
		  (map->pr_mflags & MA_READ) != 0,
		  (map->pr_mflags & MA_WRITE) != 0,
		  (map->pr_mflags & MA_EXEC) != 0,
		  1, /* MODIFIED is unknown, pass it as true.  */
		  false,
		  data);
}

/* External interface.  Calls a callback function once for each
   mapped memory region in the child process, passing as arguments:

	CORE_ADDR virtual_address,
	unsigned long size,
	int read,	TRUE if region is readable by the child
	int write,	TRUE if region is writable by the child
	int execute	TRUE if region is executable by the child.

   Stops iterating and returns the first non-zero value returned by
   the callback.  */

int
procfs_target::find_memory_regions (find_memory_region_ftype func, void *data)
{
  procinfo *pi = find_procinfo_or_die (inferior_ptid.pid (), 0);

  return iterate_over_mappings (pi, func, data,
				find_memory_regions_callback);
}

/* Returns an ascii representation of a memory mapping's flags.  */

static char *
mappingflags (long flags)
{
  static char asciiflags[8];

  strcpy (asciiflags, "-------");
  if (flags & MA_STACK)
    asciiflags[1] = 's';
  if (flags & MA_BREAK)
    asciiflags[2] = 'b';
  if (flags & MA_SHARED)
    asciiflags[3] = 's';
  if (flags & MA_READ)
    asciiflags[4] = 'r';
  if (flags & MA_WRITE)
    asciiflags[5] = 'w';
  if (flags & MA_EXEC)
    asciiflags[6] = 'x';
  return (asciiflags);
}

/* Callback function, does the actual work for 'info proc
   mappings'.  */

static int
info_mappings_callback (struct prmap *map, find_memory_region_ftype ignore,
			void *unused)
{
  unsigned int pr_off;

  pr_off = (unsigned int) map->pr_offset;

  if (gdbarch_addr_bit (current_inferior ()->arch ()) == 32)
    gdb_printf ("\t%#10lx %#10lx %#10lx %#10x %7s\n",
		(unsigned long) map->pr_vaddr,
		(unsigned long) map->pr_vaddr + map->pr_size - 1,
		(unsigned long) map->pr_size,
		pr_off,
		mappingflags (map->pr_mflags));
  else
    gdb_printf ("  %#18lx %#18lx %#10lx %#10x %7s\n",
		(unsigned long) map->pr_vaddr,
		(unsigned long) map->pr_vaddr + map->pr_size - 1,
		(unsigned long) map->pr_size,
		pr_off,
		mappingflags (map->pr_mflags));

  return 0;
}

/* Implement the "info proc mappings" subcommand.  */

static void
info_proc_mappings (procinfo *pi, int summary)
{
  if (summary)
    return;	/* No output for summary mode.  */

  gdb_printf (_("Mapped address spaces:\n\n"));
  if (gdbarch_ptr_bit (current_inferior ()->arch ()) == 32)
    gdb_printf ("\t%10s %10s %10s %10s %7s\n",
		"Start Addr",
		"  End Addr",
		"      Size",
		"    Offset",
		"Flags");
  else
    gdb_printf ("  %18s %18s %10s %10s %7s\n",
		"Start Addr",
		"  End Addr",
		"      Size",
		"    Offset",
		"Flags");

  iterate_over_mappings (pi, NULL, NULL, info_mappings_callback);
  gdb_printf ("\n");
}

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

bool
procfs_target::info_proc (const char *args, enum info_proc_what what)
{
  procinfo *process  = NULL;
  procinfo *thread   = NULL;
  char     *tmp      = NULL;
  int       pid      = 0;
  int       tid      = 0;
  int       mappings = 0;

  switch (what)
    {
    case IP_MINIMAL:
      break;

    case IP_MAPPINGS:
    case IP_ALL:
      mappings = 1;
      break;

    default:
      error (_("Not supported on this target."));
    }

  gdb_argv built_argv (args);
  for (char *arg : built_argv)
    {
      if (isdigit (arg[0]))
	{
	  pid = strtoul (arg, &tmp, 10);
	  if (*tmp == '/')
	    tid = strtoul (++tmp, NULL, 10);
	}
      else if (arg[0] == '/')
	{
	  tid = strtoul (arg + 1, NULL, 10);
	}
    }

  procinfo_up temporary_procinfo;
  if (pid == 0)
    pid = inferior_ptid.pid ();
  if (pid == 0)
    error (_("No current process: you must name one."));
  else
    {
      /* Have pid, will travel.
	 First see if it's a process we're already debugging.  */
      process = find_procinfo (pid, 0);
       if (process == NULL)
	 {
	   /* No.  So open a procinfo for it, but
	      remember to close it again when finished.  */
	   process = create_procinfo (pid, 0);
	   temporary_procinfo.reset (process);
	   if (!open_procinfo_files (process, FD_CTL))
	     proc_error (process, "info proc, open_procinfo_files", __LINE__);
	 }
    }
  if (tid != 0)
    thread = create_procinfo (pid, tid);

  if (process)
    {
      gdb_printf (_("process %d flags:\n"), process->pid);
      proc_prettyprint_flags (proc_flags (process), 1);
      if (proc_flags (process) & (PR_STOPPED | PR_ISTOP))
	proc_prettyprint_why (proc_why (process), proc_what (process), 1);
      if (proc_get_nthreads (process) > 1)
	gdb_printf ("Process has %d threads.\n",
		    proc_get_nthreads (process));
    }
  if (thread)
    {
      gdb_printf (_("thread %d flags:\n"), thread->tid);
      proc_prettyprint_flags (proc_flags (thread), 1);
      if (proc_flags (thread) & (PR_STOPPED | PR_ISTOP))
	proc_prettyprint_why (proc_why (thread), proc_what (thread), 1);
    }

  if (mappings)
    info_proc_mappings (process, 0);

  return true;
}

/* Modify the status of the system call identified by SYSCALLNUM in
   the set of syscalls that are currently traced/debugged.

   If ENTRY_OR_EXIT is set to PR_SYSENTRY, then the entry syscalls set
   will be updated.  Otherwise, the exit syscalls set will be updated.

   If MODE is FLAG_SET, then traces will be enabled.  Otherwise, they
   will be disabled.  */

static void
proc_trace_syscalls_1 (procinfo *pi, int syscallnum, int entry_or_exit,
		       int mode, int from_tty)
{
  sysset_t *sysset;

  if (entry_or_exit == PR_SYSENTRY)
    sysset = proc_get_traced_sysentry (pi, NULL);
  else
    sysset = proc_get_traced_sysexit (pi, NULL);

  if (sysset == NULL)
    proc_error (pi, "proc-trace, get_traced_sysset", __LINE__);

  if (mode == FLAG_SET)
    praddset (sysset, syscallnum);
  else
    prdelset (sysset, syscallnum);

  if (entry_or_exit == PR_SYSENTRY)
    {
      if (!proc_set_traced_sysentry (pi, sysset))
	proc_error (pi, "proc-trace, set_traced_sysentry", __LINE__);
    }
  else
    {
      if (!proc_set_traced_sysexit (pi, sysset))
	proc_error (pi, "proc-trace, set_traced_sysexit", __LINE__);
    }
}

static void
proc_trace_syscalls (const char *args, int from_tty, int entry_or_exit, int mode)
{
  procinfo *pi;

  if (inferior_ptid.pid () <= 0)
    error (_("you must be debugging a process to use this command."));

  if (args == NULL || args[0] == 0)
    error_no_arg (_("system call to trace"));

  pi = find_procinfo_or_die (inferior_ptid.pid (), 0);
  if (isdigit (args[0]))
    {
      const int syscallnum = atoi (args);

      proc_trace_syscalls_1 (pi, syscallnum, entry_or_exit, mode, from_tty);
    }
}

static void
proc_trace_sysentry_cmd (const char *args, int from_tty)
{
  proc_trace_syscalls (args, from_tty, PR_SYSENTRY, FLAG_SET);
}

static void
proc_trace_sysexit_cmd (const char *args, int from_tty)
{
  proc_trace_syscalls (args, from_tty, PR_SYSEXIT, FLAG_SET);
}

static void
proc_untrace_sysentry_cmd (const char *args, int from_tty)
{
  proc_trace_syscalls (args, from_tty, PR_SYSENTRY, FLAG_RESET);
}

static void
proc_untrace_sysexit_cmd (const char *args, int from_tty)
{
  proc_trace_syscalls (args, from_tty, PR_SYSEXIT, FLAG_RESET);
}

void _initialize_procfs ();
void
_initialize_procfs ()
{
  add_com ("proc-trace-entry", no_class, proc_trace_sysentry_cmd,
	   _("Give a trace of entries into the syscall."));
  add_com ("proc-trace-exit", no_class, proc_trace_sysexit_cmd,
	   _("Give a trace of exits from the syscall."));
  add_com ("proc-untrace-entry", no_class, proc_untrace_sysentry_cmd,
	   _("Cancel a trace of entries into the syscall."));
  add_com ("proc-untrace-exit", no_class, proc_untrace_sysexit_cmd,
	   _("Cancel a trace of exits from the syscall."));

  add_inf_child_target (&the_procfs_target);
}

/* =================== END, GDB  "MODULE" =================== */



/* miscellaneous stubs: */

/* The following satisfy a few random symbols mostly created by the
   solaris threads implementation, which I will chase down later.  */

/* Return a pid for which we guarantee we will be able to find a
   'live' procinfo.  */

ptid_t
procfs_first_available (void)
{
  return ptid_t (procinfo_list ? procinfo_list->pid : -1);
}

/* ===================  GCORE .NOTE "MODULE" =================== */

static void
procfs_do_thread_registers (bfd *obfd, ptid_t ptid,
			    gdb::unique_xmalloc_ptr<char> &note_data,
			    int *note_size, enum gdb_signal stop_signal)
{
  struct regcache *regcache = get_thread_regcache (&the_procfs_target, ptid);
  gdb_gregset_t gregs;
  gdb_fpregset_t fpregs;
  unsigned long merged_pid;

  merged_pid = ptid.lwp () << 16 | ptid.pid ();

  /* This part is the old method for fetching registers.
     It should be replaced by the newer one using regsets
     once it is implemented in this platform:
     gdbarch_iterate_over_regset_sections().  */

  target_fetch_registers (regcache, -1);

  fill_gregset (regcache, &gregs, -1);
  note_data.reset (elfcore_write_lwpstatus (obfd,
					    note_data.release (),
					    note_size,
					    merged_pid,
					    stop_signal,
					    &gregs));
  fill_fpregset (regcache, &fpregs, -1);
  note_data.reset (elfcore_write_prfpreg (obfd,
					  note_data.release (),
					  note_size,
					  &fpregs,
					  sizeof (fpregs)));
}

struct procfs_corefile_thread_data
{
  procfs_corefile_thread_data (bfd *obfd,
			       gdb::unique_xmalloc_ptr<char> &note_data,
			       int *note_size, gdb_signal stop_signal)
    : obfd (obfd), note_data (note_data), note_size (note_size),
      stop_signal (stop_signal)
  {}

  bfd *obfd;
  gdb::unique_xmalloc_ptr<char> &note_data;
  int *note_size;
  enum gdb_signal stop_signal;
};

static int
procfs_corefile_thread_callback (procinfo *pi, procinfo *thread, void *data)
{
  struct procfs_corefile_thread_data *args
    = (struct procfs_corefile_thread_data *) data;

  if (pi != NULL)
    {
      ptid_t ptid = ptid_t (pi->pid, thread->tid, 0);

      procfs_do_thread_registers (args->obfd, ptid,
				  args->note_data,
				  args->note_size,
				  args->stop_signal);
    }
  return 0;
}

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

  return 0;
}

static enum gdb_signal
find_stop_signal (void)
{
  struct thread_info *info =
    iterate_over_threads (find_signalled_thread, NULL);

  if (info)
    return info->stop_signal ();
  else
    return GDB_SIGNAL_0;
}

gdb::unique_xmalloc_ptr<char>
procfs_target::make_corefile_notes (bfd *obfd, int *note_size)
{
  gdb_gregset_t gregs;
  char fname[16] = {'\0'};
  char psargs[80] = {'\0'};
  procinfo *pi = find_procinfo_or_die (inferior_ptid.pid (), 0);
  gdb::unique_xmalloc_ptr<char> note_data;
  enum gdb_signal stop_signal;

  if (get_exec_file (0))
    {
      strncpy (fname, lbasename (get_exec_file (0)), sizeof (fname));
      fname[sizeof (fname) - 1] = 0;
      strncpy (psargs, get_exec_file (0), sizeof (psargs));
      psargs[sizeof (psargs) - 1] = 0;

      const std::string &inf_args = current_inferior ()->args ();
      if (!inf_args.empty () &&
	  inf_args.length () < ((int) sizeof (psargs) - (int) strlen (psargs)))
	{
	  strncat (psargs, " ",
		   sizeof (psargs) - strlen (psargs));
	  strncat (psargs, inf_args.c_str (),
		   sizeof (psargs) - strlen (psargs));
	}
    }

  note_data.reset (elfcore_write_prpsinfo (obfd,
					   note_data.release (),
					   note_size,
					   fname,
					   psargs));

  stop_signal = find_stop_signal ();

  fill_gregset (get_thread_regcache (inferior_thread ()), &gregs, -1);
  note_data.reset (elfcore_write_pstatus (obfd, note_data.release (), note_size,
					  inferior_ptid.pid (),
					  stop_signal, &gregs));

  procfs_corefile_thread_data thread_args (obfd, note_data, note_size,
					   stop_signal);
  proc_iterate_over_threads (pi, procfs_corefile_thread_callback,
			     &thread_args);

  std::optional<gdb::byte_vector> auxv =
    target_read_alloc (current_inferior ()->top_target (),
		       TARGET_OBJECT_AUXV, NULL);
  if (auxv && !auxv->empty ())
    note_data.reset (elfcore_write_note (obfd, note_data.release (), note_size,
					 "CORE", NT_AUXV, auxv->data (),
					 auxv->size ()));

  return note_data;
}
/* ===================  END GCORE .NOTE "MODULE" =================== */