summaryrefslogtreecommitdiffstats
path: root/usr.sbin/freebsd-update/freebsd-update.sh
blob: 7250f6e07211622a7cb67b7f419311e243919564 (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
#!/bin/sh

#-
# Copyright 2004-2007 Colin Percival
# All rights reserved
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted providing that the following conditions 
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

# $FreeBSD$

#### Usage function -- called from command-line handling code.

# Usage instructions.  Options not listed:
# --debug	-- don't filter output from utilities
# --no-stats	-- don't show progress statistics while fetching files
usage () {
	cat <<EOF
usage: `basename $0` [options] command ... [path]

Options:
  -b basedir   -- Operate on a system mounted at basedir
                  (default: /)
  -d workdir   -- Store working files in workdir
                  (default: /var/db/freebsd-update/)
  -f conffile  -- Read configuration options from conffile
                  (default: /etc/freebsd-update.conf)
  -k KEY       -- Trust an RSA key with SHA256 hash of KEY
  -r release   -- Target for upgrade (e.g., 6.2-RELEASE)
  -s server    -- Server from which to fetch updates
                  (default: update.FreeBSD.org)
  -t address   -- Mail output of cron command, if any, to address
                  (default: root)
Commands:
  fetch        -- Fetch updates from server
  cron         -- Sleep rand(3600) seconds, fetch updates, and send an
                  email if updates were found
  upgrade      -- Fetch upgrades to FreeBSD version specified via -r option
  install      -- Install downloaded updates or upgrades
  rollback     -- Uninstall most recently installed updates
  IDS          -- Compare the system against an index of "known good" files.
EOF
	exit 0
}

#### Configuration processing functions

#-
# Configuration options are set in the following order of priority:
# 1. Command line options
# 2. Configuration file options
# 3. Default options
# In addition, certain options (e.g., IgnorePaths) can be specified multiple
# times and (as long as these are all in the same place, e.g., inside the
# configuration file) they will accumulate.  Finally, because the path to the
# configuration file can be specified at the command line, the entire command
# line must be processed before we start reading the configuration file.
#
# Sound like a mess?  It is.  Here's how we handle this:
# 1. Initialize CONFFILE and all the options to "".
# 2. Process the command line.  Throw an error if a non-accumulating option
#    is specified twice.
# 3. If CONFFILE is "", set CONFFILE to /etc/freebsd-update.conf .
# 4. For all the configuration options X, set X_saved to X.
# 5. Initialize all the options to "".
# 6. Read CONFFILE line by line, parsing options.
# 7. For each configuration option X, set X to X_saved iff X_saved is not "".
# 8. Repeat steps 4-7, except setting options to their default values at (6).

CONFIGOPTIONS="KEYPRINT WORKDIR SERVERNAME MAILTO ALLOWADD ALLOWDELETE
    KEEPMODIFIEDMETADATA COMPONENTS IGNOREPATHS UPDATEIFUNMODIFIED
    BASEDIR VERBOSELEVEL TARGETRELEASE STRICTCOMPONENTS MERGECHANGES
    IDSIGNOREPATHS BACKUPKERNEL BACKUPKERNELDIR BACKUPKERNELSYMBOLFILES"

# Set all the configuration options to "".
nullconfig () {
	for X in ${CONFIGOPTIONS}; do
		eval ${X}=""
	done
}

# For each configuration option X, set X_saved to X.
saveconfig () {
	for X in ${CONFIGOPTIONS}; do
		eval ${X}_saved=\$${X}
	done
}

# For each configuration option X, set X to X_saved if X_saved is not "".
mergeconfig () {
	for X in ${CONFIGOPTIONS}; do
		eval _=\$${X}_saved
		if ! [ -z "${_}" ]; then
			eval ${X}=\$${X}_saved
		fi
	done
}

# Set the trusted keyprint.
config_KeyPrint () {
	if [ -z ${KEYPRINT} ]; then
		KEYPRINT=$1
	else
		return 1
	fi
}

# Set the working directory.
config_WorkDir () {
	if [ -z ${WORKDIR} ]; then
		WORKDIR=$1
	else
		return 1
	fi
}

# Set the name of the server (pool) from which to fetch updates
config_ServerName () {
	if [ -z ${SERVERNAME} ]; then
		SERVERNAME=$1
	else
		return 1
	fi
}

# Set the address to which 'cron' output will be mailed.
config_MailTo () {
	if [ -z ${MAILTO} ]; then
		MAILTO=$1
	else
		return 1
	fi
}

# Set whether FreeBSD Update is allowed to add files (or directories, or
# symlinks) which did not previously exist.
config_AllowAdd () {
	if [ -z ${ALLOWADD} ]; then
		case $1 in
		[Yy][Ee][Ss])
			ALLOWADD=yes
			;;
		[Nn][Oo])
			ALLOWADD=no
			;;
		*)
			return 1
			;;
		esac
	else
		return 1
	fi
}

# Set whether FreeBSD Update is allowed to remove files/directories/symlinks.
config_AllowDelete () {
	if [ -z ${ALLOWDELETE} ]; then
		case $1 in
		[Yy][Ee][Ss])
			ALLOWDELETE=yes
			;;
		[Nn][Oo])
			ALLOWDELETE=no
			;;
		*)
			return 1
			;;
		esac
	else
		return 1
	fi
}

# Set whether FreeBSD Update should keep existing inode ownership,
# permissions, and flags, in the event that they have been modified locally
# after the release.
config_KeepModifiedMetadata () {
	if [ -z ${KEEPMODIFIEDMETADATA} ]; then
		case $1 in
		[Yy][Ee][Ss])
			KEEPMODIFIEDMETADATA=yes
			;;
		[Nn][Oo])
			KEEPMODIFIEDMETADATA=no
			;;
		*)
			return 1
			;;
		esac
	else
		return 1
	fi
}

# Add to the list of components which should be kept updated.
config_Components () {
	for C in $@; do
		COMPONENTS="${COMPONENTS} ${C}"
	done
}

# Add to the list of paths under which updates will be ignored.
config_IgnorePaths () {
	for C in $@; do
		IGNOREPATHS="${IGNOREPATHS} ${C}"
	done
}

# Add to the list of paths which IDS should ignore.
config_IDSIgnorePaths () {
	for C in $@; do
		IDSIGNOREPATHS="${IDSIGNOREPATHS} ${C}"
	done
}

# Add to the list of paths within which updates will be performed only if the
# file on disk has not been modified locally.
config_UpdateIfUnmodified () {
	for C in $@; do
		UPDATEIFUNMODIFIED="${UPDATEIFUNMODIFIED} ${C}"
	done
}

# Add to the list of paths within which updates to text files will be merged
# instead of overwritten.
config_MergeChanges () {
	for C in $@; do
		MERGECHANGES="${MERGECHANGES} ${C}"
	done
}

# Work on a FreeBSD installation mounted under $1
config_BaseDir () {
	if [ -z ${BASEDIR} ]; then
		BASEDIR=$1
	else
		return 1
	fi
}

# When fetching upgrades, should we assume the user wants exactly the
# components listed in COMPONENTS, rather than trying to guess based on
# what's currently installed?
config_StrictComponents () {
	if [ -z ${STRICTCOMPONENTS} ]; then
		case $1 in
		[Yy][Ee][Ss])
			STRICTCOMPONENTS=yes
			;;
		[Nn][Oo])
			STRICTCOMPONENTS=no
			;;
		*)
			return 1
			;;
		esac
	else
		return 1
	fi
}

# Upgrade to FreeBSD $1
config_TargetRelease () {
	if [ -z ${TARGETRELEASE} ]; then
		TARGETRELEASE=$1
	else
		return 1
	fi
	if echo ${TARGETRELEASE} | grep -qE '^[0-9.]+$'; then
		TARGETRELEASE="${TARGETRELEASE}-RELEASE"
	fi
}

# Define what happens to output of utilities
config_VerboseLevel () {
	if [ -z ${VERBOSELEVEL} ]; then
		case $1 in
		[Dd][Ee][Bb][Uu][Gg])
			VERBOSELEVEL=debug
			;;
		[Nn][Oo][Ss][Tt][Aa][Tt][Ss])
			VERBOSELEVEL=nostats
			;;
		[Ss][Tt][Aa][Tt][Ss])
			VERBOSELEVEL=stats
			;;
		*)
			return 1
			;;
		esac
	else
		return 1
	fi
}

config_BackupKernel () {
	if [ -z ${BACKUPKERNEL} ]; then
		case $1 in
		[Yy][Ee][Ss])
			BACKUPKERNEL=yes
			;;
		[Nn][Oo])
			BACKUPKERNEL=no
			;;
		*)
			return 1
			;;
		esac
	else
		return 1
	fi
}

config_BackupKernelDir () {
	if [ -z ${BACKUPKERNELDIR} ]; then
		if [ -z "$1" ]; then
			echo "BackupKernelDir set to empty dir"
			return 1
		fi

		# We check for some paths which would be extremely odd
		# to use, but which could cause a lot of problems if
		# used.
		case $1 in
		/|/bin|/boot|/etc|/lib|/libexec|/sbin|/usr|/var)
			echo "BackupKernelDir set to invalid path $1"
			return 1
			;;
		/*)
			BACKUPKERNELDIR=$1
			;;
		*)
			echo "BackupKernelDir ($1) is not an absolute path"
			return 1
			;;
		esac
	else
		return 1
	fi
}

config_BackupKernelSymbolFiles () {
	if [ -z ${BACKUPKERNELSYMBOLFILES} ]; then
		case $1 in
		[Yy][Ee][Ss])
			BACKUPKERNELSYMBOLFILES=yes
			;;
		[Nn][Oo])
			BACKUPKERNELSYMBOLFILES=no
			;;
		*)
			return 1
			;;
		esac
	else
		return 1
	fi
}

# Handle one line of configuration
configline () {
	if [ $# -eq 0 ]; then
		return
	fi

	OPT=$1
	shift
	config_${OPT} $@
}

#### Parameter handling functions.

# Initialize parameters to null, just in case they're
# set in the environment.
init_params () {
	# Configration settings
	nullconfig

	# No configuration file set yet
	CONFFILE=""

	# No commands specified yet
	COMMANDS=""
}

# Parse the command line
parse_cmdline () {
	while [ $# -gt 0 ]; do
		case "$1" in
		# Location of configuration file
		-f)
			if [ $# -eq 1 ]; then usage; fi
			if [ ! -z "${CONFFILE}" ]; then usage; fi
			shift; CONFFILE="$1"
			;;

		# Configuration file equivalents
		-b)
			if [ $# -eq 1 ]; then usage; fi; shift
			config_BaseDir $1 || usage
			;;
		-d)
			if [ $# -eq 1 ]; then usage; fi; shift
			config_WorkDir $1 || usage
			;;
		-k)
			if [ $# -eq 1 ]; then usage; fi; shift
			config_KeyPrint $1 || usage
			;;
		-s)
			if [ $# -eq 1 ]; then usage; fi; shift
			config_ServerName $1 || usage
			;;
		-r)
			if [ $# -eq 1 ]; then usage; fi; shift
			config_TargetRelease $1 || usage
			;;
		-t)
			if [ $# -eq 1 ]; then usage; fi; shift
			config_MailTo $1 || usage
			;;
		-v)
			if [ $# -eq 1 ]; then usage; fi; shift
			config_VerboseLevel $1 || usage
			;;

		# Aliases for "-v debug" and "-v nostats"
		--debug)
			config_VerboseLevel debug || usage
			;;
		--no-stats)
			config_VerboseLevel nostats || usage
			;;

		# Commands
		cron | fetch | upgrade | install | rollback | IDS)
			COMMANDS="${COMMANDS} $1"
			;;

		# Anything else is an error
		*)
			usage
			;;
		esac
		shift
	done

	# Make sure we have at least one command
	if [ -z "${COMMANDS}" ]; then
		usage
	fi
}

# Parse the configuration file
parse_conffile () {
	# If a configuration file was specified on the command line, check
	# that it exists and is readable.
	if [ ! -z "${CONFFILE}" ] && [ ! -r "${CONFFILE}" ]; then
		echo -n "File does not exist "
		echo -n "or is not readable: "
		echo ${CONFFILE}
		exit 1
	fi

	# If a configuration file was not specified on the command line,
	# use the default configuration file path.  If that default does
	# not exist, give up looking for any configuration.
	if [ -z "${CONFFILE}" ]; then
		CONFFILE="/etc/freebsd-update.conf"
		if [ ! -r "${CONFFILE}" ]; then
			return
		fi
	fi

	# Save the configuration options specified on the command line, and
	# clear all the options in preparation for reading the config file.
	saveconfig
	nullconfig

	# Read the configuration file.  Anything after the first '#' is
	# ignored, and any blank lines are ignored.
	L=0
	while read LINE; do
		L=$(($L + 1))
		LINEX=`echo "${LINE}" | cut -f 1 -d '#'`
		if ! configline ${LINEX}; then
			echo "Error processing configuration file, line $L:"
			echo "==> ${LINE}"
			exit 1
		fi
	done < ${CONFFILE}

	# Merge the settings read from the configuration file with those
	# provided at the command line.
	mergeconfig
}

# Provide some default parameters
default_params () {
	# Save any parameters already configured, and clear the slate
	saveconfig
	nullconfig

	# Default configurations
	config_WorkDir /var/db/freebsd-update
	config_MailTo root
	config_AllowAdd yes
	config_AllowDelete yes
	config_KeepModifiedMetadata yes
	config_BaseDir /
	config_VerboseLevel stats
	config_StrictComponents no
	config_BackupKernel yes
	config_BackupKernelDir /boot/kernel.old
	config_BackupKernelSymbolFiles no

	# Merge these defaults into the earlier-configured settings
	mergeconfig
}

# Set utility output filtering options, based on ${VERBOSELEVEL}
fetch_setup_verboselevel () {
	case ${VERBOSELEVEL} in
	debug)
		QUIETREDIR="/dev/stderr"
		QUIETFLAG=" "
		STATSREDIR="/dev/stderr"
		DDSTATS=".."
		XARGST="-t"
		NDEBUG=" "
		;;
	nostats)
		QUIETREDIR=""
		QUIETFLAG=""
		STATSREDIR="/dev/null"
		DDSTATS=".."
		XARGST=""
		NDEBUG=""
		;;
	stats)
		QUIETREDIR="/dev/null"
		QUIETFLAG="-q"
		STATSREDIR="/dev/stdout"
		DDSTATS=""
		XARGST=""
		NDEBUG="-n"
		;;
	esac
}

# Perform sanity checks and set some final parameters
# in preparation for fetching files.  Figure out which
# set of updates should be downloaded: If the user is
# running *-p[0-9]+, strip off the last part; if the
# user is running -SECURITY, call it -RELEASE.  Chdir
# into the working directory.
fetchupgrade_check_params () {
	export HTTP_USER_AGENT="freebsd-update (${COMMAND}, `uname -r`)"

	_SERVERNAME_z=\
"SERVERNAME must be given via command line or configuration file."
	_KEYPRINT_z="Key must be given via -k option or configuration file."
	_KEYPRINT_bad="Invalid key fingerprint: "
	_WORKDIR_bad="Directory does not exist or is not writable: "

	if [ -z "${SERVERNAME}" ]; then
		echo -n "`basename $0`: "
		echo "${_SERVERNAME_z}"
		exit 1
	fi
	if [ -z "${KEYPRINT}" ]; then
		echo -n "`basename $0`: "
		echo "${_KEYPRINT_z}"
		exit 1
	fi
	if ! echo "${KEYPRINT}" | grep -qE "^[0-9a-f]{64}$"; then
		echo -n "`basename $0`: "
		echo -n "${_KEYPRINT_bad}"
		echo ${KEYPRINT}
		exit 1
	fi
	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
		echo -n "`basename $0`: "
		echo -n "${_WORKDIR_bad}"
		echo ${WORKDIR}
		exit 1
	fi
	chmod 700 ${WORKDIR}
	cd ${WORKDIR} || exit 1

	# Generate release number.  The s/SECURITY/RELEASE/ bit exists
	# to provide an upgrade path for FreeBSD Update 1.x users, since
	# the kernels provided by FreeBSD Update 1.x are always labelled
	# as X.Y-SECURITY.
	RELNUM=`uname -r |
	    sed -E 's,-p[0-9]+,,' |
	    sed -E 's,-SECURITY,-RELEASE,'`
	ARCH=`uname -m`
	FETCHDIR=${RELNUM}/${ARCH}
	PATCHDIR=${RELNUM}/${ARCH}/bp

	# Figure out what directory contains the running kernel
	BOOTFILE=`sysctl -n kern.bootfile`
	KERNELDIR=${BOOTFILE%/kernel}
	if ! [ -d ${KERNELDIR} ]; then
		echo "Cannot identify running kernel"
		exit 1
	fi

	# Figure out what kernel configuration is running.  We start with
	# the output of `uname -i`, and then make the following adjustments:
	# 1. Replace "SMP-GENERIC" with "SMP".  Why the SMP kernel config
	# file says "ident SMP-GENERIC", I don't know...
	# 2. If the kernel claims to be GENERIC _and_ ${ARCH} is "amd64"
	# _and_ `sysctl kern.version` contains a line which ends "/SMP", then
	# we're running an SMP kernel.  This mis-identification is a bug
	# which was fixed in 6.2-STABLE.
	KERNCONF=`uname -i`
	if [ ${KERNCONF} = "SMP-GENERIC" ]; then
		KERNCONF=SMP
	fi
	if [ ${KERNCONF} = "GENERIC" ] && [ ${ARCH} = "amd64" ]; then
		if sysctl kern.version | grep -qE '/SMP$'; then
			KERNCONF=SMP
		fi
	fi

	# Define some paths
	BSPATCH=/usr/bin/bspatch
	SHA256=/sbin/sha256
	PHTTPGET=/usr/libexec/phttpget

	# Set up variables relating to VERBOSELEVEL
	fetch_setup_verboselevel

	# Construct a unique name from ${BASEDIR}
	BDHASH=`echo ${BASEDIR} | sha256 -q`
}

# Perform sanity checks etc. before fetching updates.
fetch_check_params () {
	fetchupgrade_check_params

	if ! [ -z "${TARGETRELEASE}" ]; then
		echo -n "`basename $0`: "
		echo -n "-r option is meaningless with 'fetch' command.  "
		echo "(Did you mean 'upgrade' instead?)"
		exit 1
	fi
}

# Perform sanity checks etc. before fetching upgrades.
upgrade_check_params () {
	fetchupgrade_check_params

	# Unless set otherwise, we're upgrading to the same kernel config.
	NKERNCONF=${KERNCONF}

	# We need TARGETRELEASE set
	_TARGETRELEASE_z="Release target must be specified via -r option."
	if [ -z "${TARGETRELEASE}" ]; then
		echo -n "`basename $0`: "
		echo "${_TARGETRELEASE_z}"
		exit 1
	fi

	# The target release should be != the current release.
	if [ "${TARGETRELEASE}" = "${RELNUM}" ]; then
		echo -n "`basename $0`: "
		echo "Cannot upgrade from ${RELNUM} to itself"
		exit 1
	fi

	# Turning off AllowAdd or AllowDelete is a bad idea for upgrades.
	if [ "${ALLOWADD}" = "no" ]; then
		echo -n "`basename $0`: "
		echo -n "WARNING: \"AllowAdd no\" is a bad idea "
		echo "when upgrading between releases."
		echo
	fi
	if [ "${ALLOWDELETE}" = "no" ]; then
		echo -n "`basename $0`: "
		echo -n "WARNING: \"AllowDelete no\" is a bad idea "
		echo "when upgrading between releases."
		echo
	fi

	# Set EDITOR to /usr/bin/vi if it isn't already set
	: ${EDITOR:='/usr/bin/vi'}
}

# Perform sanity checks and set some final parameters in
# preparation for installing updates.
install_check_params () {
	# Check that we are root.  All sorts of things won't work otherwise.
	if [ `id -u` != 0 ]; then
		echo "You must be root to run this."
		exit 1
	fi

	# Check that securelevel <= 0.  Otherwise we can't update schg files.
	if [ `sysctl -n kern.securelevel` -gt 0 ]; then
		echo "Updates cannot be installed when the system securelevel"
		echo "is greater than zero."
		exit 1
	fi

	# Check that we have a working directory
	_WORKDIR_bad="Directory does not exist or is not writable: "
	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
		echo -n "`basename $0`: "
		echo -n "${_WORKDIR_bad}"
		echo ${WORKDIR}
		exit 1
	fi
	cd ${WORKDIR} || exit 1

	# Construct a unique name from ${BASEDIR}
	BDHASH=`echo ${BASEDIR} | sha256 -q`

	# Check that we have updates ready to install
	if ! [ -L ${BDHASH}-install ]; then
		echo "No updates are available to install."
		echo "Run '$0 fetch' first."
		exit 1
	fi
	if ! [ -f ${BDHASH}-install/INDEX-OLD ] ||
	    ! [ -f ${BDHASH}-install/INDEX-NEW ]; then
		echo "Update manifest is corrupt -- this should never happen."
		echo "Re-run '$0 fetch'."
		exit 1
	fi

	# Figure out what directory contains the running kernel
	BOOTFILE=`sysctl -n kern.bootfile`
	KERNELDIR=${BOOTFILE%/kernel}
	if ! [ -d ${KERNELDIR} ]; then
		echo "Cannot identify running kernel"
		exit 1
	fi
}

# Perform sanity checks and set some final parameters in
# preparation for UNinstalling updates.
rollback_check_params () {
	# Check that we are root.  All sorts of things won't work otherwise.
	if [ `id -u` != 0 ]; then
		echo "You must be root to run this."
		exit 1
	fi

	# Check that we have a working directory
	_WORKDIR_bad="Directory does not exist or is not writable: "
	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
		echo -n "`basename $0`: "
		echo -n "${_WORKDIR_bad}"
		echo ${WORKDIR}
		exit 1
	fi
	cd ${WORKDIR} || exit 1

	# Construct a unique name from ${BASEDIR}
	BDHASH=`echo ${BASEDIR} | sha256 -q`

	# Check that we have updates ready to rollback
	if ! [ -L ${BDHASH}-rollback ]; then
		echo "No rollback directory found."
		exit 1
	fi
	if ! [ -f ${BDHASH}-rollback/INDEX-OLD ] ||
	    ! [ -f ${BDHASH}-rollback/INDEX-NEW ]; then
		echo "Update manifest is corrupt -- this should never happen."
		exit 1
	fi
}

# Perform sanity checks and set some final parameters
# in preparation for comparing the system against the
# published index.  Figure out which index we should
# compare against: If the user is running *-p[0-9]+,
# strip off the last part; if the user is running
# -SECURITY, call it -RELEASE.  Chdir into the working
# directory.
IDS_check_params () {
	export HTTP_USER_AGENT="freebsd-update (${COMMAND}, `uname -r`)"

	_SERVERNAME_z=\
"SERVERNAME must be given via command line or configuration file."
	_KEYPRINT_z="Key must be given via -k option or configuration file."
	_KEYPRINT_bad="Invalid key fingerprint: "
	_WORKDIR_bad="Directory does not exist or is not writable: "

	if [ -z "${SERVERNAME}" ]; then
		echo -n "`basename $0`: "
		echo "${_SERVERNAME_z}"
		exit 1
	fi
	if [ -z "${KEYPRINT}" ]; then
		echo -n "`basename $0`: "
		echo "${_KEYPRINT_z}"
		exit 1
	fi
	if ! echo "${KEYPRINT}" | grep -qE "^[0-9a-f]{64}$"; then
		echo -n "`basename $0`: "
		echo -n "${_KEYPRINT_bad}"
		echo ${KEYPRINT}
		exit 1
	fi
	if ! [ -d "${WORKDIR}" -a -w "${WORKDIR}" ]; then
		echo -n "`basename $0`: "
		echo -n "${_WORKDIR_bad}"
		echo ${WORKDIR}
		exit 1
	fi
	cd ${WORKDIR} || exit 1

	# Generate release number.  The s/SECURITY/RELEASE/ bit exists
	# to provide an upgrade path for FreeBSD Update 1.x users, since
	# the kernels provided by FreeBSD Update 1.x are always labelled
	# as X.Y-SECURITY.
	RELNUM=`uname -r |
	    sed -E 's,-p[0-9]+,,' |
	    sed -E 's,-SECURITY,-RELEASE,'`
	ARCH=`uname -m`
	FETCHDIR=${RELNUM}/${ARCH}
	PATCHDIR=${RELNUM}/${ARCH}/bp

	# Figure out what directory contains the running kernel
	BOOTFILE=`sysctl -n kern.bootfile`
	KERNELDIR=${BOOTFILE%/kernel}
	if ! [ -d ${KERNELDIR} ]; then
		echo "Cannot identify running kernel"
		exit 1
	fi

	# Figure out what kernel configuration is running.  We start with
	# the output of `uname -i`, and then make the following adjustments:
	# 1. Replace "SMP-GENERIC" with "SMP".  Why the SMP kernel config
	# file says "ident SMP-GENERIC", I don't know...
	# 2. If the kernel claims to be GENERIC _and_ ${ARCH} is "amd64"
	# _and_ `sysctl kern.version` contains a line which ends "/SMP", then
	# we're running an SMP kernel.  This mis-identification is a bug
	# which was fixed in 6.2-STABLE.
	KERNCONF=`uname -i`
	if [ ${KERNCONF} = "SMP-GENERIC" ]; then
		KERNCONF=SMP
	fi
	if [ ${KERNCONF} = "GENERIC" ] && [ ${ARCH} = "amd64" ]; then
		if sysctl kern.version | grep -qE '/SMP$'; then
			KERNCONF=SMP
		fi
	fi

	# Define some paths
	SHA256=/sbin/sha256
	PHTTPGET=/usr/libexec/phttpget

	# Set up variables relating to VERBOSELEVEL
	fetch_setup_verboselevel
}

#### Core functionality -- the actual work gets done here

# Use an SRV query to pick a server.  If the SRV query doesn't provide
# a useful answer, use the server name specified by the user.
# Put another way... look up _http._tcp.${SERVERNAME} and pick a server
# from that; or if no servers are returned, use ${SERVERNAME}.
# This allows a user to specify "portsnap.freebsd.org" (in which case
# portsnap will select one of the mirrors) or "portsnap5.tld.freebsd.org"
# (in which case portsnap will use that particular server, since there
# won't be an SRV entry for that name).
#
# We ignore the Port field, since we are always going to use port 80.

# Fetch the mirror list, but do not pick a mirror yet.  Returns 1 if
# no mirrors are available for any reason.
fetch_pick_server_init () {
	: > serverlist_tried

# Check that host(1) exists (i.e., that the system wasn't built with the
# WITHOUT_BIND set) and don't try to find a mirror if it doesn't exist.
	if ! which -s host; then
		: > serverlist_full
		return 1
	fi

	echo -n "Looking up ${SERVERNAME} mirrors... "

# Issue the SRV query and pull out the Priority, Weight, and Target fields.
# BIND 9 prints "$name has SRV record ..." while BIND 8 prints
# "$name server selection ..."; we allow either format.
	MLIST="_http._tcp.${SERVERNAME}"
	host -t srv "${MLIST}" |
	    sed -nE "s/${MLIST} (has SRV record|server selection) //p" |
	    cut -f 1,2,4 -d ' ' |
	    sed -e 's/\.$//' |
	    sort > serverlist_full

# If no records, give up -- we'll just use the server name we were given.
	if [ `wc -l < serverlist_full` -eq 0 ]; then
		echo "none found."
		return 1
	fi

# Report how many mirrors we found.
	echo `wc -l < serverlist_full` "mirrors found."

# Generate a random seed for use in picking mirrors.  If HTTP_PROXY
# is set, this will be used to generate the seed; otherwise, the seed
# will be random.
	if [ -n "${HTTP_PROXY}${http_proxy}" ]; then
		RANDVALUE=`sha256 -qs "${HTTP_PROXY}${http_proxy}" |
		    tr -d 'a-f' |
		    cut -c 1-9`
	else
		RANDVALUE=`jot -r 1 0 999999999`
	fi
}

# Pick a mirror.  Returns 1 if we have run out of mirrors to try.
fetch_pick_server () {
# Generate a list of not-yet-tried mirrors
	sort serverlist_tried |
	    comm -23 serverlist_full - > serverlist

# Have we run out of mirrors?
	if [ `wc -l < serverlist` -eq 0 ]; then
		echo "No mirrors remaining, giving up."
		return 1
	fi

# Find the highest priority level (lowest numeric value).
	SRV_PRIORITY=`cut -f 1 -d ' ' serverlist | sort -n | head -1`

# Add up the weights of the response lines at that priority level.
	SRV_WSUM=0;
	while read X; do
		case "$X" in
		${SRV_PRIORITY}\ *)
			SRV_W=`echo $X | cut -f 2 -d ' '`
			SRV_WSUM=$(($SRV_WSUM + $SRV_W))
			;;
		esac
	done < serverlist

# If all the weights are 0, pretend that they are all 1 instead.
	if [ ${SRV_WSUM} -eq 0 ]; then
		SRV_WSUM=`grep -E "^${SRV_PRIORITY} " serverlist | wc -l`
		SRV_W_ADD=1
	else
		SRV_W_ADD=0
	fi

# Pick a value between 0 and the sum of the weights - 1
	SRV_RND=`expr ${RANDVALUE} % ${SRV_WSUM}`

# Read through the list of mirrors and set SERVERNAME.  Write the line
# corresponding to the mirror we selected into serverlist_tried so that
# we won't try it again.
	while read X; do
		case "$X" in
		${SRV_PRIORITY}\ *)
			SRV_W=`echo $X | cut -f 2 -d ' '`
			SRV_W=$(($SRV_W + $SRV_W_ADD))
			if [ $SRV_RND -lt $SRV_W ]; then
				SERVERNAME=`echo $X | cut -f 3 -d ' '`
				echo "$X" >> serverlist_tried
				break
			else
				SRV_RND=$(($SRV_RND - $SRV_W))
			fi
			;;
		esac
	done < serverlist
}

# Take a list of ${oldhash}|${newhash} and output a list of needed patches,
# i.e., those for which we have ${oldhash} and don't have ${newhash}.
fetch_make_patchlist () {
	grep -vE "^([0-9a-f]{64})\|\1$" |
	    tr '|' ' ' |
		while read X Y; do
			if [ -f "files/${Y}.gz" ] ||
			    [ ! -f "files/${X}.gz" ]; then
				continue
			fi
			echo "${X}|${Y}"
		done | uniq
}

# Print user-friendly progress statistics
fetch_progress () {
	LNC=0
	while read x; do
		LNC=$(($LNC + 1))
		if [ $(($LNC % 10)) = 0 ]; then
			echo -n $LNC
		elif [ $(($LNC % 2)) = 0 ]; then
			echo -n .
		fi
	done
	echo -n " "
}

# Function for asking the user if everything is ok
continuep () {
	while read -p "Does this look reasonable (y/n)? " CONTINUE; do
		case "${CONTINUE}" in
		y*)
			return 0
			;;
		n*)
			return 1
			;;
		esac
	done
}

# Initialize the working directory
workdir_init () {
	mkdir -p files
	touch tINDEX.present
}

# Check that we have a public key with an appropriate hash, or
# fetch the key if it doesn't exist.  Returns 1 if the key has
# not yet been fetched.
fetch_key () {
	if [ -r pub.ssl ] && [ `${SHA256} -q pub.ssl` = ${KEYPRINT} ]; then
		return 0
	fi

	echo -n "Fetching public key from ${SERVERNAME}... "
	rm -f pub.ssl
	fetch ${QUIETFLAG} http://${SERVERNAME}/${FETCHDIR}/pub.ssl \
	    2>${QUIETREDIR} || true
	if ! [ -r pub.ssl ]; then
		echo "failed."
		return 1
	fi
	if ! [ `${SHA256} -q pub.ssl` = ${KEYPRINT} ]; then
		echo "key has incorrect hash."
		rm -f pub.ssl
		return 1
	fi
	echo "done."
}

# Fetch metadata signature, aka "tag".
fetch_tag () {
	echo -n "Fetching metadata signature "
	echo ${NDEBUG} "for ${RELNUM} from ${SERVERNAME}... "
	rm -f latest.ssl
	fetch ${QUIETFLAG} http://${SERVERNAME}/${FETCHDIR}/latest.ssl	\
	    2>${QUIETREDIR} || true
	if ! [ -r latest.ssl ]; then
		echo "failed."
		return 1
	fi

	openssl rsautl -pubin -inkey pub.ssl -verify		\
	    < latest.ssl > tag.new 2>${QUIETREDIR} || true
	rm latest.ssl

	if ! [ `wc -l < tag.new` = 1 ] ||
	    ! grep -qE	\
    "^freebsd-update\|${ARCH}\|${RELNUM}\|[0-9]+\|[0-9a-f]{64}\|[0-9]{10}" \
		tag.new; then
		echo "invalid signature."
		return 1
	fi

	echo "done."

	RELPATCHNUM=`cut -f 4 -d '|' < tag.new`
	TINDEXHASH=`cut -f 5 -d '|' < tag.new`
	EOLTIME=`cut -f 6 -d '|' < tag.new`
}

# Sanity-check the patch number in a tag, to make sure that we're not
# going to "update" backwards and to prevent replay attacks.
fetch_tagsanity () {
	# Check that we're not going to move from -pX to -pY with Y < X.
	RELPX=`uname -r | sed -E 's,.*-,,'`
	if echo ${RELPX} | grep -qE '^p[0-9]+$'; then
		RELPX=`echo ${RELPX} | cut -c 2-`
	else
		RELPX=0
	fi
	if [ "${RELPATCHNUM}" -lt "${RELPX}" ]; then
		echo
		echo -n "Files on mirror (${RELNUM}-p${RELPATCHNUM})"
		echo " appear older than what"
		echo "we are currently running (`uname -r`)!"
		echo "Cowardly refusing to proceed any further."
		return 1
	fi

	# If "tag" exists and corresponds to ${RELNUM}, make sure that
	# it contains a patch number <= RELPATCHNUM, in order to protect
	# against rollback (replay) attacks.
	if [ -f tag ] &&
	    grep -qE	\
    "^freebsd-update\|${ARCH}\|${RELNUM}\|[0-9]+\|[0-9a-f]{64}\|[0-9]{10}" \
		tag; then
		LASTRELPATCHNUM=`cut -f 4 -d '|' < tag`

		if [ "${RELPATCHNUM}" -lt "${LASTRELPATCHNUM}" ]; then
			echo
			echo -n "Files on mirror (${RELNUM}-p${RELPATCHNUM})"
			echo " are older than the"
			echo -n "most recently seen updates"
			echo " (${RELNUM}-p${LASTRELPATCHNUM})."
			echo "Cowardly refusing to proceed any further."
			return 1
		fi
	fi
}

# Fetch metadata index file
fetch_metadata_index () {
	echo ${NDEBUG} "Fetching metadata index... "
	rm -f ${TINDEXHASH}
	fetch ${QUIETFLAG} http://${SERVERNAME}/${FETCHDIR}/t/${TINDEXHASH}
	    2>${QUIETREDIR}
	if ! [ -f ${TINDEXHASH} ]; then
		echo "failed."
		return 1
	fi
	if [ `${SHA256} -q ${TINDEXHASH}` != ${TINDEXHASH} ]; then
		echo "update metadata index corrupt."
		return 1
	fi
	echo "done."
}

# Print an error message about signed metadata being bogus.
fetch_metadata_bogus () {
	echo
	echo "The update metadata$1 is correctly signed, but"
	echo "failed an integrity check."
	echo "Cowardly refusing to proceed any further."
	return 1
}

# Construct tINDEX.new by merging the lines named in $1 from ${TINDEXHASH}
# with the lines not named in $@ from tINDEX.present (if that file exists).
fetch_metadata_index_merge () {
	for METAFILE in $@; do
		if [ `grep -E "^${METAFILE}\|" ${TINDEXHASH} | wc -l`	\
		    -ne 1 ]; then
			fetch_metadata_bogus " index"
			return 1
		fi

		grep -E "${METAFILE}\|" ${TINDEXHASH}
	done |
	    sort > tINDEX.wanted

	if [ -f tINDEX.present ]; then
		join -t '|' -v 2 tINDEX.wanted tINDEX.present |
		    sort -m - tINDEX.wanted > tINDEX.new
		rm tINDEX.wanted
	else
		mv tINDEX.wanted tINDEX.new
	fi
}

# Sanity check all the lines of tINDEX.new.  Even if more metadata lines
# are added by future versions of the server, this won't cause problems,
# since the only lines which appear in tINDEX.new are the ones which we
# specifically grepped out of ${TINDEXHASH}.
fetch_metadata_index_sanity () {
	if grep -qvE '^[0-9A-Z.-]+\|[0-9a-f]{64}$' tINDEX.new; then
		fetch_metadata_bogus " index"
		return 1
	fi
}

# Sanity check the metadata file $1.
fetch_metadata_sanity () {
	# Some aliases to save space later: ${P} is a character which can
	# appear in a path; ${M} is the four numeric metadata fields; and
	# ${H} is a sha256 hash.
	P="[-+./:=%@_[~[:alnum:]]"
	M="[0-9]+\|[0-9]+\|[0-9]+\|[0-9]+"
	H="[0-9a-f]{64}"

	# Check that the first four fields make sense.
	if gunzip -c < files/$1.gz |
	    grep -qvE "^[a-z]+\|[0-9a-z]+\|${P}+\|[fdL-]\|"; then
		fetch_metadata_bogus ""
		return 1
	fi

	# Remove the first three fields.
	gunzip -c < files/$1.gz |
	    cut -f 4- -d '|' > sanitycheck.tmp

	# Sanity check entries with type 'f'
	if grep -E '^f' sanitycheck.tmp |
	    grep -qvE "^f\|${M}\|${H}\|${P}*\$"; then
		fetch_metadata_bogus ""
		return 1
	fi

	# Sanity check entries with type 'd'
	if grep -E '^d' sanitycheck.tmp |
	    grep -qvE "^d\|${M}\|\|\$"; then
		fetch_metadata_bogus ""
		return 1
	fi

	# Sanity check entries with type 'L'
	if grep -E '^L' sanitycheck.tmp |
	    grep -qvE "^L\|${M}\|${P}*\|\$"; then
		fetch_metadata_bogus ""
		return 1
	fi

	# Sanity check entries with type '-'
	if grep -E '^-' sanitycheck.tmp |
	    grep -qvE "^-\|\|\|\|\|\|"; then
		fetch_metadata_bogus ""
		return 1
	fi

	# Clean up
	rm sanitycheck.tmp
}

# Fetch the metadata index and metadata files listed in $@,
# taking advantage of metadata patches where possible.
fetch_metadata () {
	fetch_metadata_index || return 1
	fetch_metadata_index_merge $@ || return 1
	fetch_metadata_index_sanity || return 1

	# Generate a list of wanted metadata patches
	join -t '|' -o 1.2,2.2 tINDEX.present tINDEX.new |
	    fetch_make_patchlist > patchlist

	if [ -s patchlist ]; then
		# Attempt to fetch metadata patches
		echo -n "Fetching `wc -l < patchlist | tr -d ' '` "
		echo ${NDEBUG} "metadata patches.${DDSTATS}"
		tr '|' '-' < patchlist |
		    lam -s "${FETCHDIR}/tp/" - -s ".gz" |
		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
			2>${STATSREDIR} | fetch_progress
		echo "done."

		# Attempt to apply metadata patches
		echo -n "Applying metadata patches... "
		tr '|' ' ' < patchlist |
		    while read X Y; do
			if [ ! -f "${X}-${Y}.gz" ]; then continue; fi
			gunzip -c < ${X}-${Y}.gz > diff
			gunzip -c < files/${X}.gz > diff-OLD

			# Figure out which lines are being added and removed
			grep -E '^-' diff |
			    cut -c 2- |
			    while read PREFIX; do
				look "${PREFIX}" diff-OLD
			    done |
			    sort > diff-rm
			grep -E '^\+' diff |
			    cut -c 2- > diff-add

			# Generate the new file
			comm -23 diff-OLD diff-rm |
			    sort - diff-add > diff-NEW

			if [ `${SHA256} -q diff-NEW` = ${Y} ]; then
				mv diff-NEW files/${Y}
				gzip -n files/${Y}
			else
				mv diff-NEW ${Y}.bad
			fi
			rm -f ${X}-${Y}.gz diff
			rm -f diff-OLD diff-NEW diff-add diff-rm
		done 2>${QUIETREDIR}
		echo "done."
	fi

	# Update metadata without patches
	cut -f 2 -d '|' < tINDEX.new |
	    while read Y; do
		if [ ! -f "files/${Y}.gz" ]; then
			echo ${Y};
		fi
	    done |
	    sort -u > filelist

	if [ -s filelist ]; then
		echo -n "Fetching `wc -l < filelist | tr -d ' '` "
		echo ${NDEBUG} "metadata files... "
		lam -s "${FETCHDIR}/m/" - -s ".gz" < filelist |
		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
		    2>${QUIETREDIR}

		while read Y; do
			if ! [ -f ${Y}.gz ]; then
				echo "failed."
				return 1
			fi
			if [ `gunzip -c < ${Y}.gz |
			    ${SHA256} -q` = ${Y} ]; then
				mv ${Y}.gz files/${Y}.gz
			else
				echo "metadata is corrupt."
				return 1
			fi
		done < filelist
		echo "done."
	fi

# Sanity-check the metadata files.
	cut -f 2 -d '|' tINDEX.new > filelist
	while read X; do
		fetch_metadata_sanity ${X} || return 1
	done < filelist

# Remove files which are no longer needed
	cut -f 2 -d '|' tINDEX.present |
	    sort > oldfiles
	cut -f 2 -d '|' tINDEX.new |
	    sort |
	    comm -13 - oldfiles |
	    lam -s "files/" - -s ".gz" |
	    xargs rm -f
	rm patchlist filelist oldfiles
	rm ${TINDEXHASH}

# We're done!
	mv tINDEX.new tINDEX.present
	mv tag.new tag

	return 0
}

# Extract a subset of a downloaded metadata file containing only the parts
# which are listed in COMPONENTS.
fetch_filter_metadata_components () {
	METAHASH=`look "$1|" tINDEX.present | cut -f 2 -d '|'`
	gunzip -c < files/${METAHASH}.gz > $1.all

	# Fish out the lines belonging to components we care about.
	for C in ${COMPONENTS}; do
		look "`echo ${C} | tr '/' '|'`|" $1.all
	done > $1

	# Remove temporary file.
	rm $1.all
}

# Generate a filtered version of the metadata file $1 from the downloaded
# file, by fishing out the lines corresponding to components we're trying
# to keep updated, and then removing lines corresponding to paths we want
# to ignore.
fetch_filter_metadata () {
	# Fish out the lines belonging to components we care about.
	fetch_filter_metadata_components $1

	# Canonicalize directory names by removing any trailing / in
	# order to avoid listing directories multiple times if they
	# belong to multiple components.  Turning "/" into "" doesn't
	# matter, since we add a leading "/" when we use paths later.
	cut -f 3- -d '|' $1 |
	    sed -e 's,/|d|,|d|,' |
	    sed -e 's,/|-|,|-|,' |
	    sort -u > $1.tmp

	# Figure out which lines to ignore and remove them.
	for X in ${IGNOREPATHS}; do
		grep -E "^${X}" $1.tmp
	done |
	    sort -u |
	    comm -13 - $1.tmp > $1

	# Remove temporary files.
	rm $1.tmp
}

# Filter the metadata file $1 by adding lines with "/boot/$2"
# replaced by ${KERNELDIR} (which is `sysctl -n kern.bootfile` minus the
# trailing "/kernel"); and if "/boot/$2" does not exist, remove
# the original lines which start with that.
# Put another way: Deal with the fact that the FOO kernel is sometimes
# installed in /boot/FOO/ and is sometimes installed elsewhere.
fetch_filter_kernel_names () {
	grep ^/boot/$2 $1 |
	    sed -e "s,/boot/$2,${KERNELDIR},g" |
	    sort - $1 > $1.tmp
	mv $1.tmp $1

	if ! [ -d /boot/$2 ]; then
		grep -v ^/boot/$2 $1 > $1.tmp
		mv $1.tmp $1
	fi
}

# For all paths appearing in $1 or $3, inspect the system
# and generate $2 describing what is currently installed.
fetch_inspect_system () {
	# No errors yet...
	rm -f .err

	# Tell the user why his disk is suddenly making lots of noise
	echo -n "Inspecting system... "

	# Generate list of files to inspect
	cat $1 $3 |
	    cut -f 1 -d '|' |
	    sort -u > filelist

	# Examine each file and output lines of the form
	# /path/to/file|type|device-inum|user|group|perm|flags|value
	# sorted by device and inode number.
	while read F; do
		# If the symlink/file/directory does not exist, record this.
		if ! [ -e ${BASEDIR}/${F} ]; then
			echo "${F}|-||||||"
			continue
		fi
		if ! [ -r ${BASEDIR}/${F} ]; then
			echo "Cannot read file: ${BASEDIR}/${F}"	\
			    >/dev/stderr
			touch .err
			return 1
		fi

		# Otherwise, output an index line.
		if [ -L ${BASEDIR}/${F} ]; then
			echo -n "${F}|L|"
			stat -n -f '%d-%i|%u|%g|%Mp%Lp|%Of|' ${BASEDIR}/${F};
			readlink ${BASEDIR}/${F};
		elif [ -f ${BASEDIR}/${F} ]; then
			echo -n "${F}|f|"
			stat -n -f '%d-%i|%u|%g|%Mp%Lp|%Of|' ${BASEDIR}/${F};
			sha256 -q ${BASEDIR}/${F};
		elif [ -d ${BASEDIR}/${F} ]; then
			echo -n "${F}|d|"
			stat -f '%d-%i|%u|%g|%Mp%Lp|%Of|' ${BASEDIR}/${F};
		else
			echo "Unknown file type: ${BASEDIR}/${F}"	\
			    >/dev/stderr
			touch .err
			return 1
		fi
	done < filelist |
	    sort -k 3,3 -t '|' > $2.tmp
	rm filelist

	# Check if an error occurred during system inspection
	if [ -f .err ]; then
		return 1
	fi

	# Convert to the form
	# /path/to/file|type|user|group|perm|flags|value|hlink
	# by resolving identical device and inode numbers into hard links.
	cut -f 1,3 -d '|' $2.tmp |
	    sort -k 1,1 -t '|' |
	    sort -s -u -k 2,2 -t '|' |
	    join -1 2 -2 3 -t '|' - $2.tmp |
	    awk -F \| -v OFS=\|		\
		'{
		    if (($2 == $3) || ($4 == "-"))
			print $3,$4,$5,$6,$7,$8,$9,""
		    else
			print $3,$4,$5,$6,$7,$8,$9,$2
		}' |
	    sort > $2
	rm $2.tmp

	# We're finished looking around
	echo "done."
}

# For any paths matching ${MERGECHANGES}, compare $1 and $2 and find any
# files which differ; generate $3 containing these paths and the old hashes.
fetch_filter_mergechanges () {
	# Pull out the paths and hashes of the files matching ${MERGECHANGES}.
	for F in $1 $2; do
		for X in ${MERGECHANGES}; do
			grep -E "^${X}" ${F}
		done |
		    cut -f 1,2,7 -d '|' |
		    sort > ${F}-values
	done

	# Any line in $2-values which doesn't appear in $1-values and is a
	# file means that we should list the path in $3.
	comm -13 $1-values $2-values |
	    fgrep '|f|' |
	    cut -f 1 -d '|' > $2-paths

	# For each path, pull out one (and only one!) entry from $1-values.
	# Note that we cannot distinguish which "old" version the user made
	# changes to; but hopefully any changes which occur due to security
	# updates will exist in both the "new" version and the version which
	# the user has installed, so the merging will still work.
	while read X; do
		look "${X}|" $1-values |
		    head -1
	done < $2-paths > $3

	# Clean up
	rm $1-values $2-values $2-paths
}

# For any paths matching ${UPDATEIFUNMODIFIED}, remove lines from $[123]
# which correspond to lines in $2 with hashes not matching $1 or $3, unless
# the paths are listed in $4.  For entries in $2 marked "not present"
# (aka. type -), remove lines from $[123] unless there is a corresponding
# entry in $1.
fetch_filter_unmodified_notpresent () {
	# Figure out which lines of $1 and $3 correspond to bits which
	# should only be updated if they haven't changed, and fish out
	# the (path, type, value) tuples.
	# NOTE: We don't consider a file to be "modified" if it matches
	# the hash from $3.
	for X in ${UPDATEIFUNMODIFIED}; do
		grep -E "^${X}" $1
		grep -E "^${X}" $3
	done |
	    cut -f 1,2,7 -d '|' |
	    sort > $1-values

	# Do the same for $2.
	for X in ${UPDATEIFUNMODIFIED}; do
		grep -E "^${X}" $2
	done |
	    cut -f 1,2,7 -d '|' |
	    sort > $2-values

	# Any entry in $2-values which is not in $1-values corresponds to
	# a path which we need to remove from $1, $2, and $3, unless it
	# that path appears in $4.
	comm -13 $1-values $2-values |
	    sort -t '|' -k 1,1 > mlines.tmp
	cut -f 1 -d '|' $4 |
	    sort |
	    join -v 2 -t '|' - mlines.tmp |
	    sort > mlines
	rm $1-values $2-values mlines.tmp

	# Any lines in $2 which are not in $1 AND are "not present" lines
	# also belong in mlines.
	comm -13 $1 $2 |
	    cut -f 1,2,7 -d '|' |
	    fgrep '|-|' >> mlines

	# Remove lines from $1, $2, and $3
	for X in $1 $2 $3; do
		sort -t '|' -k 1,1 ${X} > ${X}.tmp
		cut -f 1 -d '|' < mlines |
		    sort |
		    join -v 2 -t '|' - ${X}.tmp |
		    sort > ${X}
		rm ${X}.tmp
	done

	# Store a list of the modified files, for future reference
	fgrep -v '|-|' mlines |
	    cut -f 1 -d '|' > modifiedfiles
	rm mlines
}

# For each entry in $1 of type -, remove any corresponding
# entry from $2 if ${ALLOWADD} != "yes".  Remove all entries
# of type - from $1.
fetch_filter_allowadd () {
	cut -f 1,2 -d '|' < $1 |
	    fgrep '|-' |
	    cut -f 1 -d '|' > filesnotpresent

	if [ ${ALLOWADD} != "yes" ]; then
		sort < $2 |
		    join -v 1 -t '|' - filesnotpresent |
		    sort > $2.tmp
		mv $2.tmp $2
	fi

	sort < $1 |
	    join -v 1 -t '|' - filesnotpresent |
	    sort > $1.tmp
	mv $1.tmp $1
	rm filesnotpresent
}

# If ${ALLOWDELETE} != "yes", then remove any entries from $1
# which don't correspond to entries in $2.
fetch_filter_allowdelete () {
	# Produce a lists ${PATH}|${TYPE}
	for X in $1 $2; do
		cut -f 1-2 -d '|' < ${X} |
		    sort -u > ${X}.nodes
	done

	# Figure out which lines need to be removed from $1.
	if [ ${ALLOWDELETE} != "yes" ]; then
		comm -23 $1.nodes $2.nodes > $1.badnodes
	else
		: > $1.badnodes
	fi

	# Remove the relevant lines from $1
	while read X; do
		look "${X}|" $1
	done < $1.badnodes |
	    comm -13 - $1 > $1.tmp
	mv $1.tmp $1

	rm $1.badnodes $1.nodes $2.nodes
}

# If ${KEEPMODIFIEDMETADATA} == "yes", then for each entry in $2
# with metadata not matching any entry in $1, replace the corresponding
# line of $3 with one having the same metadata as the entry in $2.
fetch_filter_modified_metadata () {
	# Fish out the metadata from $1 and $2
	for X in $1 $2; do
		cut -f 1-6 -d '|' < ${X} > ${X}.metadata
	done

	# Find the metadata we need to keep
	if [ ${KEEPMODIFIEDMETADATA} = "yes" ]; then
		comm -13 $1.metadata $2.metadata > keepmeta
	else
		: > keepmeta
	fi

	# Extract the lines which we need to remove from $3, and
	# construct the lines which we need to add to $3.
	: > $3.remove
	: > $3.add
	while read LINE; do
		NODE=`echo "${LINE}" | cut -f 1-2 -d '|'`
		look "${NODE}|" $3 >> $3.remove
		look "${NODE}|" $3 |
		    cut -f 7- -d '|' |
		    lam -s "${LINE}|" - >> $3.add
	done < keepmeta

	# Remove the specified lines and add the new lines.
	sort $3.remove |
	    comm -13 - $3 |
	    sort -u - $3.add > $3.tmp
	mv $3.tmp $3

	rm keepmeta $1.metadata $2.metadata $3.add $3.remove
}

# Remove lines from $1 and $2 which are identical;
# no need to update a file if it isn't changing.
fetch_filter_uptodate () {
	comm -23 $1 $2 > $1.tmp
	comm -13 $1 $2 > $2.tmp

	mv $1.tmp $1
	mv $2.tmp $2
}

# Fetch any "clean" old versions of files we need for merging changes.
fetch_files_premerge () {
	# We only need to do anything if $1 is non-empty.
	if [ -s $1 ]; then
		# Tell the user what we're doing
		echo -n "Fetching files from ${OLDRELNUM} for merging... "

		# List of files wanted
		fgrep '|f|' < $1 |
		    cut -f 3 -d '|' |
		    sort -u > files.wanted

		# Only fetch the files we don't already have
		while read Y; do
			if [ ! -f "files/${Y}.gz" ]; then
				echo ${Y};
			fi
		done < files.wanted > filelist

		# Actually fetch them
		lam -s "${OLDFETCHDIR}/f/" - -s ".gz" < filelist |
		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
		    2>${QUIETREDIR}

		# Make sure we got them all, and move them into /files/
		while read Y; do
			if ! [ -f ${Y}.gz ]; then
				echo "failed."
				return 1
			fi
			if [ `gunzip -c < ${Y}.gz |
			    ${SHA256} -q` = ${Y} ]; then
				mv ${Y}.gz files/${Y}.gz
			else
				echo "${Y} has incorrect hash."
				return 1
			fi
		done < filelist
		echo "done."

		# Clean up
		rm filelist files.wanted
	fi
}

# Prepare to fetch files: Generate a list of the files we need,
# copy the unmodified files we have into /files/, and generate
# a list of patches to download.
fetch_files_prepare () {
	# Tell the user why his disk is suddenly making lots of noise
	echo -n "Preparing to download files... "

	# Reduce indices to ${PATH}|${HASH} pairs
	for X in $1 $2 $3; do
		cut -f 1,2,7 -d '|' < ${X} |
		    fgrep '|f|' |
		    cut -f 1,3 -d '|' |
		    sort > ${X}.hashes
	done

	# List of files wanted
	cut -f 2 -d '|' < $3.hashes |
	    sort -u |
	    while read HASH; do
		if ! [ -f files/${HASH}.gz ]; then
			echo ${HASH}
		fi
	done > files.wanted

	# Generate a list of unmodified files
	comm -12 $1.hashes $2.hashes |
	    sort -k 1,1 -t '|' > unmodified.files

	# Copy all files into /files/.  We only need the unmodified files
	# for use in patching; but we'll want all of them if the user asks
	# to rollback the updates later.
	while read LINE; do
		F=`echo "${LINE}" | cut -f 1 -d '|'`
		HASH=`echo "${LINE}" | cut -f 2 -d '|'`

		# Skip files we already have.
		if [ -f files/${HASH}.gz ]; then
			continue
		fi

		# Make sure the file hasn't changed.
		cp "${BASEDIR}/${F}" tmpfile
		if [ `sha256 -q tmpfile` != ${HASH} ]; then
			echo
			echo "File changed while FreeBSD Update running: ${F}"
			return 1
		fi

		# Place the file into storage.
		gzip -c < tmpfile > files/${HASH}.gz
		rm tmpfile
	done < $2.hashes

	# Produce a list of patches to download
	sort -k 1,1 -t '|' $3.hashes |
	    join -t '|' -o 2.2,1.2 - unmodified.files |
	    fetch_make_patchlist > patchlist

	# Garbage collect
	rm unmodified.files $1.hashes $2.hashes $3.hashes

	# We don't need the list of possible old files any more.
	rm $1

	# We're finished making noise
	echo "done."
}

# Fetch files.
fetch_files () {
	# Attempt to fetch patches
	if [ -s patchlist ]; then
		echo -n "Fetching `wc -l < patchlist | tr -d ' '` "
		echo ${NDEBUG} "patches.${DDSTATS}"
		tr '|' '-' < patchlist |
		    lam -s "${PATCHDIR}/" - |
		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
			2>${STATSREDIR} | fetch_progress
		echo "done."

		# Attempt to apply patches
		echo -n "Applying patches... "
		tr '|' ' ' < patchlist |
		    while read X Y; do
			if [ ! -f "${X}-${Y}" ]; then continue; fi
			gunzip -c < files/${X}.gz > OLD

			bspatch OLD NEW ${X}-${Y}

			if [ `${SHA256} -q NEW` = ${Y} ]; then
				mv NEW files/${Y}
				gzip -n files/${Y}
			fi
			rm -f diff OLD NEW ${X}-${Y}
		done 2>${QUIETREDIR}
		echo "done."
	fi

	# Download files which couldn't be generate via patching
	while read Y; do
		if [ ! -f "files/${Y}.gz" ]; then
			echo ${Y};
		fi
	done < files.wanted > filelist

	if [ -s filelist ]; then
		echo -n "Fetching `wc -l < filelist | tr -d ' '` "
		echo ${NDEBUG} "files... "
		lam -s "${FETCHDIR}/f/" - -s ".gz" < filelist |
		    xargs ${XARGST} ${PHTTPGET} ${SERVERNAME}	\
		    2>${QUIETREDIR}

		while read Y; do
			if ! [ -f ${Y}.gz ]; then
				echo "failed."
				return 1
			fi
			if [ `gunzip -c < ${Y}.gz |
			    ${SHA256} -q` = ${Y} ]; then
				mv ${Y}.gz files/${Y}.gz
			else
				echo "${Y} has incorrect hash."
				return 1
			fi
		done < filelist
		echo "done."
	fi

	# Clean up
	rm files.wanted filelist patchlist
}

# Create and populate install manifest directory; and report what updates
# are available.
fetch_create_manifest () {
	# If we have an existing install manifest, nuke it.
	if [ -L "${BDHASH}-install" ]; then
		rm -r ${BDHASH}-install/
		rm ${BDHASH}-install
	fi

	# Report to the user if any updates were avoided due to local changes
	if [ -s modifiedfiles ]; then
		echo
		echo -n "The following files are affected by updates, "
		echo "but no changes have"
		echo -n "been downloaded because the files have been "
		echo "modified locally:"
		cat modifiedfiles
	fi | $PAGER
	rm modifiedfiles

	# If no files will be updated, tell the user and exit
	if ! [ -s INDEX-PRESENT ] &&
	    ! [ -s INDEX-NEW ]; then
		rm INDEX-PRESENT INDEX-NEW
		echo
		echo -n "No updates needed to update system to "
		echo "${RELNUM}-p${RELPATCHNUM}."
		return
	fi

	# Divide files into (a) removed files, (b) added files, and
	# (c) updated files.
	cut -f 1 -d '|' < INDEX-PRESENT |
	    sort > INDEX-PRESENT.flist
	cut -f 1 -d '|' < INDEX-NEW |
	    sort > INDEX-NEW.flist
	comm -23 INDEX-PRESENT.flist INDEX-NEW.flist > files.removed
	comm -13 INDEX-PRESENT.flist INDEX-NEW.flist > files.added
	comm -12 INDEX-PRESENT.flist INDEX-NEW.flist > files.updated
	rm INDEX-PRESENT.flist INDEX-NEW.flist

	# Report removed files, if any
	if [ -s files.removed ]; then
		echo
		echo -n "The following files will be removed "
		echo "as part of updating to ${RELNUM}-p${RELPATCHNUM}:"
		cat files.removed
	fi | $PAGER
	rm files.removed

	# Report added files, if any
	if [ -s files.added ]; then
		echo
		echo -n "The following files will be added "
		echo "as part of updating to ${RELNUM}-p${RELPATCHNUM}:"
		cat files.added
	fi | $PAGER
	rm files.added

	# Report updated files, if any
	if [ -s files.updated ]; then
		echo
		echo -n "The following files will be updated "
		echo "as part of updating to ${RELNUM}-p${RELPATCHNUM}:"

		cat files.updated
	fi | $PAGER
	rm files.updated

	# Create a directory for the install manifest.
	MDIR=`mktemp -d install.XXXXXX` || return 1

	# Populate it
	mv INDEX-PRESENT ${MDIR}/INDEX-OLD
	mv INDEX-NEW ${MDIR}/INDEX-NEW

	# Link it into place
	ln -s ${MDIR} ${BDHASH}-install
}

# Warn about any upcoming EoL
fetch_warn_eol () {
	# What's the current time?
	NOWTIME=`date "+%s"`

	# When did we last warn about the EoL date?
	if [ -f lasteolwarn ]; then
		LASTWARN=`cat lasteolwarn`
	else
		LASTWARN=`expr ${NOWTIME} - 63072000`
	fi

	# If the EoL time is past, warn.
	if [ ${EOLTIME} -lt ${NOWTIME} ]; then
		echo
		cat <<-EOF
		WARNING: `uname -sr` HAS PASSED ITS END-OF-LIFE DATE.
		Any security issues discovered after `date -r ${EOLTIME}`
		will not have been corrected.
		EOF
		return 1
	fi

	# Figure out how long it has been since we last warned about the
	# upcoming EoL, and how much longer we have left.
	SINCEWARN=`expr ${NOWTIME} - ${LASTWARN}`
	TIMELEFT=`expr ${EOLTIME} - ${NOWTIME}`

	# Don't warn if the EoL is more than 3 months away
	if [ ${TIMELEFT} -gt 7884000 ]; then
		return 0
	fi

	# Don't warn if the time remaining is more than 3 times the time
	# since the last warning.
	if [ ${TIMELEFT} -gt `expr ${SINCEWARN} \* 3` ]; then
		return 0
	fi

	# Figure out what time units to use.
	if [ ${TIMELEFT} -lt 604800 ]; then
		UNIT="day"
		SIZE=86400
	elif [ ${TIMELEFT} -lt 2678400 ]; then
		UNIT="week"
		SIZE=604800
	else
		UNIT="month"
		SIZE=2678400
	fi

	# Compute the right number of units
	NUM=`expr ${TIMELEFT} / ${SIZE}`
	if [ ${NUM} != 1 ]; then
		UNIT="${UNIT}s"
	fi

	# Print the warning
	echo
	cat <<-EOF
		WARNING: `uname -sr` is approaching its End-of-Life date.
		It is strongly recommended that you upgrade to a newer
		release within the next ${NUM} ${UNIT}.
	EOF

	# Update the stored time of last warning
	echo ${NOWTIME} > lasteolwarn
}

# Do the actual work involved in "fetch" / "cron".
fetch_run () {
	workdir_init || return 1

	# Prepare the mirror list.
	fetch_pick_server_init && fetch_pick_server

	# Try to fetch the public key until we run out of servers.
	while ! fetch_key; do
		fetch_pick_server || return 1
	done

	# Try to fetch the metadata index signature ("tag") until we run
	# out of available servers; and sanity check the downloaded tag.
	while ! fetch_tag; do
		fetch_pick_server || return 1
	done
	fetch_tagsanity || return 1

	# Fetch the latest INDEX-NEW and INDEX-OLD files.
	fetch_metadata INDEX-NEW INDEX-OLD || return 1

	# Generate filtered INDEX-NEW and INDEX-OLD files containing only
	# the lines which (a) belong to components we care about, and (b)
	# don't correspond to paths we're explicitly ignoring.
	fetch_filter_metadata INDEX-NEW || return 1
	fetch_filter_metadata INDEX-OLD || return 1

	# Translate /boot/${KERNCONF} into ${KERNELDIR}
	fetch_filter_kernel_names INDEX-NEW ${KERNCONF}
	fetch_filter_kernel_names INDEX-OLD ${KERNCONF}

	# For all paths appearing in INDEX-OLD or INDEX-NEW, inspect the
	# system and generate an INDEX-PRESENT file.
	fetch_inspect_system INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1

	# Based on ${UPDATEIFUNMODIFIED}, remove lines from INDEX-* which
	# correspond to lines in INDEX-PRESENT with hashes not appearing
	# in INDEX-OLD or INDEX-NEW.  Also remove lines where the entry in
	# INDEX-PRESENT has type - and there isn't a corresponding entry in
	# INDEX-OLD with type -.
	fetch_filter_unmodified_notpresent	\
	    INDEX-OLD INDEX-PRESENT INDEX-NEW /dev/null

	# For each entry in INDEX-PRESENT of type -, remove any corresponding
	# entry from INDEX-NEW if ${ALLOWADD} != "yes".  Remove all entries
	# of type - from INDEX-PRESENT.
	fetch_filter_allowadd INDEX-PRESENT INDEX-NEW

	# If ${ALLOWDELETE} != "yes", then remove any entries from
	# INDEX-PRESENT which don't correspond to entries in INDEX-NEW.
	fetch_filter_allowdelete INDEX-PRESENT INDEX-NEW

	# If ${KEEPMODIFIEDMETADATA} == "yes", then for each entry in
	# INDEX-PRESENT with metadata not matching any entry in INDEX-OLD,
	# replace the corresponding line of INDEX-NEW with one having the
	# same metadata as the entry in INDEX-PRESENT.
	fetch_filter_modified_metadata INDEX-OLD INDEX-PRESENT INDEX-NEW

	# Remove lines from INDEX-PRESENT and INDEX-NEW which are identical;
	# no need to update a file if it isn't changing.
	fetch_filter_uptodate INDEX-PRESENT INDEX-NEW

	# Prepare to fetch files: Generate a list of the files we need,
	# copy the unmodified files we have into /files/, and generate
	# a list of patches to download.
	fetch_files_prepare INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1

	# Fetch files.
	fetch_files || return 1

	# Create and populate install manifest directory; and report what
	# updates are available.
	fetch_create_manifest || return 1

	# Warn about any upcoming EoL
	fetch_warn_eol || return 1
}

# If StrictComponents is not "yes", generate a new components list
# with only the components which appear to be installed.
upgrade_guess_components () {
	if [ "${STRICTCOMPONENTS}" = "no" ]; then
		# Generate filtered INDEX-ALL with only the components listed
		# in COMPONENTS.
		fetch_filter_metadata_components $1 || return 1

		# Tell the user why his disk is suddenly making lots of noise
		echo -n "Inspecting system... "

		# Look at the files on disk, and assume that a component is
		# supposed to be present if it is more than half-present.
		cut -f 1-3 -d '|' < INDEX-ALL |
		    tr '|' ' ' |
		    while read C S F; do
			if [ -e ${BASEDIR}/${F} ]; then
				echo "+ ${C}|${S}"
			fi
			echo "= ${C}|${S}"
		    done |
		    sort |
		    uniq -c |
		    sed -E 's,^ +,,' > compfreq
		grep ' = ' compfreq |
		    cut -f 1,3 -d ' ' |
		    sort -k 2,2 -t ' ' > compfreq.total
		grep ' + ' compfreq |
		    cut -f 1,3 -d ' ' |
		    sort -k 2,2 -t ' ' > compfreq.present
		join -t ' ' -1 2 -2 2 compfreq.present compfreq.total |
		    while read S P T; do
			if [ ${P} -gt `expr ${T} / 2` ]; then
				echo ${S}
			fi
		    done > comp.present
		cut -f 2 -d ' ' < compfreq.total > comp.total
		rm INDEX-ALL compfreq compfreq.total compfreq.present

		# We're done making noise.
		echo "done."

		# Sometimes the kernel isn't installed where INDEX-ALL
		# thinks that it should be: In particular, it is often in
		# /boot/kernel instead of /boot/GENERIC or /boot/SMP.  To
		# deal with this, if "kernel|X" is listed in comp.total
		# (i.e., is a component which would be upgraded if it is
		# found to be present) we will add it to comp.present.
		# If "kernel|<anything>" is in comp.total but "kernel|X" is
		# not, we print a warning -- the user is running a kernel
		# which isn't part of the release.
		KCOMP=`echo ${KERNCONF} | tr 'A-Z' 'a-z'`
		grep -E "^kernel\|${KCOMP}\$" comp.total >> comp.present

		if grep -qE "^kernel\|" comp.total &&
		    ! grep -qE "^kernel\|${KCOMP}\$" comp.total; then
			cat <<-EOF

WARNING: This system is running a "${KCOMP}" kernel, which is not a
kernel configuration distributed as part of FreeBSD ${RELNUM}.
This kernel will not be updated: you MUST update the kernel manually
before running "$0 install".
			EOF
		fi

		# Re-sort the list of installed components and generate
		# the list of non-installed components.
		sort -u < comp.present > comp.present.tmp
		mv comp.present.tmp comp.present
		comm -13 comp.present comp.total > comp.absent

		# Ask the user to confirm that what we have is correct.  To
		# reduce user confusion, translate "X|Y" back to "X/Y" (as
		# subcomponents must be listed in the configuration file).
		echo
		echo -n "The following components of FreeBSD "
		echo "seem to be installed:"
		tr '|' '/' < comp.present |
		    fmt -72
		echo
		echo -n "The following components of FreeBSD "
		echo "do not seem to be installed:"
		tr '|' '/' < comp.absent |
		    fmt -72
		echo
		continuep || return 1
		echo

		# Suck the generated list of components into ${COMPONENTS}.
		# Note that comp.present.tmp is used due to issues with
		# pipelines and setting variables.
		COMPONENTS=""
		tr '|' '/' < comp.present > comp.present.tmp
		while read C; do
			COMPONENTS="${COMPONENTS} ${C}"
		done < comp.present.tmp

		# Delete temporary files
		rm comp.present comp.present.tmp comp.absent comp.total
	fi
}

# If StrictComponents is not "yes", COMPONENTS contains an entry
# corresponding to the currently running kernel, and said kernel
# does not exist in the new release, add "kernel/generic" to the
# list of components.
upgrade_guess_new_kernel () {
	if [ "${STRICTCOMPONENTS}" = "no" ]; then
		# Grab the unfiltered metadata file.
		METAHASH=`look "$1|" tINDEX.present | cut -f 2 -d '|'`
		gunzip -c < files/${METAHASH}.gz > $1.all

		# If "kernel/${KCOMP}" is in ${COMPONENTS} and that component
		# isn't in $1.all, we need to add kernel/generic.
		for C in ${COMPONENTS}; do
			if [ ${C} = "kernel/${KCOMP}" ] &&
			    ! grep -qE "^kernel\|${KCOMP}\|" $1.all; then
				COMPONENTS="${COMPONENTS} kernel/generic"
				NKERNCONF="GENERIC"
				cat <<-EOF

WARNING: This system is running a "${KCOMP}" kernel, which is not a
kernel configuration distributed as part of FreeBSD ${RELNUM}.
As part of upgrading to FreeBSD ${RELNUM}, this kernel will be
replaced with a "generic" kernel.
				EOF
				continuep || return 1
			fi
		done

		# Don't need this any more...
		rm $1.all
	fi
}

# Convert INDEX-OLD (last release) and INDEX-ALL (new release) into
# INDEX-OLD and INDEX-NEW files (in the sense of normal upgrades).
upgrade_oldall_to_oldnew () {
	# For each ${F}|... which appears in INDEX-ALL but does not appear
	# in INDEX-OLD, add ${F}|-|||||| to INDEX-OLD.
	cut -f 1 -d '|' < $1 |
	    sort -u > $1.paths
	cut -f 1 -d '|' < $2 |
	    sort -u |
	    comm -13 $1.paths - |
	    lam - -s "|-||||||" |
	    sort - $1 > $1.tmp
	mv $1.tmp $1

	# Remove lines from INDEX-OLD which also appear in INDEX-ALL
	comm -23 $1 $2 > $1.tmp
	mv $1.tmp $1

	# Remove lines from INDEX-ALL which have a file name not appearing
	# anywhere in INDEX-OLD (since these must be files which haven't
	# changed -- if they were new, there would be an entry of type "-").
	cut -f 1 -d '|' < $1 |
	    sort -u > $1.paths
	sort -k 1,1 -t '|' < $2 |
	    join -t '|' - $1.paths |
	    sort > $2.tmp
	rm $1.paths
	mv $2.tmp $2

	# Rename INDEX-ALL to INDEX-NEW.
	mv $2 $3
}

# Helper for upgrade_merge: Return zero true iff the two files differ only
# in the contents of their $FreeBSD$ tags.
samef () {
	X=`sed -E 's/\\$FreeBSD.*\\$/\$FreeBSD\$/' < $1 | ${SHA256}`
	Y=`sed -E 's/\\$FreeBSD.*\\$/\$FreeBSD\$/' < $2 | ${SHA256}`

	if [ $X = $Y ]; then
		return 0;
	else
		return 1;
	fi
}

# From the list of "old" files in $1, merge changes in $2 with those in $3,
# and update $3 to reflect the hashes of merged files.
upgrade_merge () {
	# We only need to do anything if $1 is non-empty.
	if [ -s $1 ]; then
		cut -f 1 -d '|' $1 |
		    sort > $1-paths

		# Create staging area for merging files
		rm -rf merge/
		while read F; do
			D=`dirname ${F}`
			mkdir -p merge/old/${D}
			mkdir -p merge/${OLDRELNUM}/${D}
			mkdir -p merge/${RELNUM}/${D}
			mkdir -p merge/new/${D}
		done < $1-paths

		# Copy in files
		while read F; do
			# Currently installed file
			V=`look "${F}|" $2 | cut -f 7 -d '|'`
			gunzip < files/${V}.gz > merge/old/${F}

			# Old release
			if look "${F}|" $1 | fgrep -q "|f|"; then
				V=`look "${F}|" $1 | cut -f 3 -d '|'`
				gunzip < files/${V}.gz		\
				    > merge/${OLDRELNUM}/${F}
			fi

			# New release
			if look "${F}|" $3 | cut -f 1,2,7 -d '|' |
			    fgrep -q "|f|"; then
				V=`look "${F}|" $3 | cut -f 7 -d '|'`
				gunzip < files/${V}.gz		\
				    > merge/${RELNUM}/${F}
			fi
		done < $1-paths

		# Attempt to automatically merge changes
		echo -n "Attempting to automatically merge "
		echo -n "changes in files..."
		: > failed.merges
		while read F; do
			# If the file doesn't exist in the new release,
			# the result of "merging changes" is having the file
			# not exist.
			if ! [ -f merge/${RELNUM}/${F} ]; then
				continue
			fi

			# If the file didn't exist in the old release, we're
			# going to throw away the existing file and hope that
			# the version from the new release is what we want.
			if ! [ -f merge/${OLDRELNUM}/${F} ]; then
				cp merge/${RELNUM}/${F} merge/new/${F}
				continue
			fi

			# Some files need special treatment.
			case ${F} in
			/etc/spwd.db | /etc/pwd.db | /etc/login.conf.db)
				# Don't merge these -- we're rebuild them
				# after updates are installed.
				cp merge/old/${F} merge/new/${F}
				;;
			*)
				if ! merge -p -L "current version"	\
				    -L "${OLDRELNUM}" -L "${RELNUM}"	\
				    merge/old/${F}			\
				    merge/${OLDRELNUM}/${F}		\
				    merge/${RELNUM}/${F}		\
				    > merge/new/${F} 2>/dev/null; then
					echo ${F} >> failed.merges
				fi
				;;
			esac
		done < $1-paths
		echo " done."

		# Ask the user to handle any files which didn't merge.
		while read F; do
			# If the installed file differs from the version in
			# the old release only due to $FreeBSD$ tag expansion
			# then just use the version in the new release.
			if samef merge/old/${F} merge/${OLDRELNUM}/${F}; then
				cp merge/${RELNUM}/${F} merge/new/${F}
				continue
			fi

			cat <<-EOF

The following file could not be merged automatically: ${F}
Press Enter to edit this file in ${EDITOR} and resolve the conflicts
manually...
			EOF
			read dummy </dev/tty
			${EDITOR} `pwd`/merge/new/${F} < /dev/tty
		done < failed.merges
		rm failed.merges

		# Ask the user to confirm that he likes how the result
		# of merging files.
		while read F; do
			# Skip files which haven't changed except possibly
			# in their $FreeBSD$ tags.
			if [ -f merge/old/${F} ] && [ -f merge/new/${F} ] &&
			    samef merge/old/${F} merge/new/${F}; then
				continue
			fi

			# Skip files where the installed file differs from
			# the old file only due to $FreeBSD$ tags.
			if [ -f merge/old/${F} ] &&
			    [ -f merge/${OLDRELNUM}/${F} ] &&
			    samef merge/old/${F} merge/${OLDRELNUM}/${F}; then
				continue
			fi

			# Warn about files which are ceasing to exist.
			if ! [ -f merge/new/${F} ]; then
				cat <<-EOF

The following file will be removed, as it no longer exists in
FreeBSD ${RELNUM}: ${F}
				EOF
				continuep < /dev/tty || return 1
				continue
			fi

			# Print changes for the user's approval.
			cat <<-EOF

The following changes, which occurred between FreeBSD ${OLDRELNUM} and
FreeBSD ${RELNUM} have been merged into ${F}:
EOF
			diff -U 5 -L "current version" -L "new version"	\
			    merge/old/${F} merge/new/${F} || true
			continuep < /dev/tty || return 1
		done < $1-paths

		# Store merged files.
		while read F; do
			if [ -f merge/new/${F} ]; then
				V=`${SHA256} -q merge/new/${F}`

				gzip -c < merge/new/${F} > files/${V}.gz
				echo "${F}|${V}"
			fi
		done < $1-paths > newhashes

		# Pull lines out from $3 which need to be updated to
		# reflect merged files.
		while read F; do
			look "${F}|" $3
		done < $1-paths > $3-oldlines

		# Update lines to reflect merged files
		join -t '|' -o 1.1,1.2,1.3,1.4,1.5,1.6,2.2,1.8		\
		    $3-oldlines newhashes > $3-newlines

		# Remove old lines from $3 and add new lines.
		sort $3-oldlines |
		    comm -13 - $3 |
		    sort - $3-newlines > $3.tmp
		mv $3.tmp $3

		# Clean up
		rm $1-paths newhashes $3-oldlines $3-newlines
		rm -rf merge/
	fi

	# We're done with merging files.
	rm $1
}

# Do the work involved in fetching upgrades to a new release
upgrade_run () {
	workdir_init || return 1

	# Prepare the mirror list.
	fetch_pick_server_init && fetch_pick_server

	# Try to fetch the public key until we run out of servers.
	while ! fetch_key; do
		fetch_pick_server || return 1
	done
 
	# Try to fetch the metadata index signature ("tag") until we run
	# out of available servers; and sanity check the downloaded tag.
	while ! fetch_tag; do
		fetch_pick_server || return 1
	done
	fetch_tagsanity || return 1

	# Fetch the INDEX-OLD and INDEX-ALL.
	fetch_metadata INDEX-OLD INDEX-ALL || return 1

	# If StrictComponents is not "yes", generate a new components list
	# with only the components which appear to be installed.
	upgrade_guess_components INDEX-ALL || return 1

	# Generate filtered INDEX-OLD and INDEX-ALL files containing only
	# the components we want and without anything marked as "Ignore".
	fetch_filter_metadata INDEX-OLD || return 1
	fetch_filter_metadata INDEX-ALL || return 1

	# Merge the INDEX-OLD and INDEX-ALL files into INDEX-OLD.
	sort INDEX-OLD INDEX-ALL > INDEX-OLD.tmp
	mv INDEX-OLD.tmp INDEX-OLD
	rm INDEX-ALL

	# Adjust variables for fetching files from the new release.
	OLDRELNUM=${RELNUM}
	RELNUM=${TARGETRELEASE}
	OLDFETCHDIR=${FETCHDIR}
	FETCHDIR=${RELNUM}/${ARCH}

	# Try to fetch the NEW metadata index signature ("tag") until we run
	# out of available servers; and sanity check the downloaded tag.
	while ! fetch_tag; do
		fetch_pick_server || return 1
	done

	# Fetch the new INDEX-ALL.
	fetch_metadata INDEX-ALL || return 1

	# If StrictComponents is not "yes", COMPONENTS contains an entry
	# corresponding to the currently running kernel, and said kernel
	# does not exist in the new release, add "kernel/generic" to the
	# list of components.
	upgrade_guess_new_kernel INDEX-ALL || return 1

	# Filter INDEX-ALL to contain only the components we want and without
	# anything marked as "Ignore".
	fetch_filter_metadata INDEX-ALL || return 1

	# Convert INDEX-OLD (last release) and INDEX-ALL (new release) into
	# INDEX-OLD and INDEX-NEW files (in the sense of normal upgrades).
	upgrade_oldall_to_oldnew INDEX-OLD INDEX-ALL INDEX-NEW

	# Translate /boot/${KERNCONF} or /boot/${NKERNCONF} into ${KERNELDIR}
	fetch_filter_kernel_names INDEX-NEW ${NKERNCONF}
	fetch_filter_kernel_names INDEX-OLD ${KERNCONF}

	# For all paths appearing in INDEX-OLD or INDEX-NEW, inspect the
	# system and generate an INDEX-PRESENT file.
	fetch_inspect_system INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1

	# Based on ${MERGECHANGES}, generate a file tomerge-old with the
	# paths and hashes of old versions of files to merge.
	fetch_filter_mergechanges INDEX-OLD INDEX-PRESENT tomerge-old

	# Based on ${UPDATEIFUNMODIFIED}, remove lines from INDEX-* which
	# correspond to lines in INDEX-PRESENT with hashes not appearing
	# in INDEX-OLD or INDEX-NEW.  Also remove lines where the entry in
	# INDEX-PRESENT has type - and there isn't a corresponding entry in
	# INDEX-OLD with type -.
	fetch_filter_unmodified_notpresent	\
	    INDEX-OLD INDEX-PRESENT INDEX-NEW tomerge-old

	# For each entry in INDEX-PRESENT of type -, remove any corresponding
	# entry from INDEX-NEW if ${ALLOWADD} != "yes".  Remove all entries
	# of type - from INDEX-PRESENT.
	fetch_filter_allowadd INDEX-PRESENT INDEX-NEW

	# If ${ALLOWDELETE} != "yes", then remove any entries from
	# INDEX-PRESENT which don't correspond to entries in INDEX-NEW.
	fetch_filter_allowdelete INDEX-PRESENT INDEX-NEW

	# If ${KEEPMODIFIEDMETADATA} == "yes", then for each entry in
	# INDEX-PRESENT with metadata not matching any entry in INDEX-OLD,
	# replace the corresponding line of INDEX-NEW with one having the
	# same metadata as the entry in INDEX-PRESENT.
	fetch_filter_modified_metadata INDEX-OLD INDEX-PRESENT INDEX-NEW

	# Remove lines from INDEX-PRESENT and INDEX-NEW which are identical;
	# no need to update a file if it isn't changing.
	fetch_filter_uptodate INDEX-PRESENT INDEX-NEW

	# Fetch "clean" files from the old release for merging changes.
	fetch_files_premerge tomerge-old

	# Prepare to fetch files: Generate a list of the files we need,
	# copy the unmodified files we have into /files/, and generate
	# a list of patches to download.
	fetch_files_prepare INDEX-OLD INDEX-PRESENT INDEX-NEW || return 1

	# Fetch patches from to-${RELNUM}/${ARCH}/bp/
	PATCHDIR=to-${RELNUM}/${ARCH}/bp
	fetch_files || return 1

	# Merge configuration file changes.
	upgrade_merge tomerge-old INDEX-PRESENT INDEX-NEW || return 1

	# Create and populate install manifest directory; and report what
	# updates are available.
	fetch_create_manifest || return 1

	# Leave a note behind to tell the "install" command that the kernel
	# needs to be installed before the world.
	touch ${BDHASH}-install/kernelfirst

	# Remind the user that they need to run "freebsd-update install"
	# to install the downloaded bits, in case they didn't RTFM.
	echo "To install the downloaded upgrades, run \"$0 install\"."
}

# Make sure that all the file hashes mentioned in $@ have corresponding
# gzipped files stored in /files/.
install_verify () {
	# Generate a list of hashes
	cat $@ |
	    cut -f 2,7 -d '|' |
	    grep -E '^f' |
	    cut -f 2 -d '|' |
	    sort -u > filelist

	# Make sure all the hashes exist
	while read HASH; do
		if ! [ -f files/${HASH}.gz ]; then
			echo -n "Update files missing -- "
			echo "this should never happen."
			echo "Re-run '$0 fetch'."
			return 1
		fi
	done < filelist

	# Clean up
	rm filelist
}

# Remove the system immutable flag from files
install_unschg () {
	# Generate file list
	cat $@ |
	    cut -f 1 -d '|' > filelist

	# Remove flags
	while read F; do
		if ! [ -e ${BASEDIR}/${F} ]; then
			continue
		fi

		chflags noschg ${BASEDIR}/${F} || return 1
	done < filelist

	# Clean up
	rm filelist
}

# Decide which directory name to use for kernel backups.
backup_kernel_finddir () {
	CNT=0
	while true ; do
		# Pathname does not exist, so it is OK use that name
		# for backup directory.
		if [ ! -e $BASEDIR/$BACKUPKERNELDIR ]; then
			return 0
		fi

		# If directory do exist, we only use if it has our
		# marker file.
		if [ -d $BASEDIR/$BACKUPKERNELDIR -a \
			-e $BASEDIR/$BACKUPKERNELDIR/.freebsd-update ]; then
			return 0
		fi

		# We could not use current directory name, so add counter to
		# the end and try again.
		CNT=$((CNT + 1))
		if [ $CNT -gt 9 ]; then
			echo "Could not find valid backup dir ($BASEDIR/$BACKUPKERNELDIR)"
			exit 1
		fi
		BACKUPKERNELDIR="`echo $BACKUPKERNELDIR | sed -Ee 's/[0-9]\$//'`"
		BACKUPKERNELDIR="${BACKUPKERNELDIR}${CNT}"
	done
}

# Backup the current kernel using hardlinks, if not disabled by user.
# Since we delete all files in the directory used for previous backups
# we create a marker file called ".freebsd-update" in the directory so
# we can determine on the next run that the directory was created by
# freebsd-update and we then do not accidentally remove user files in
# the unlikely case that the user has created a directory with a
# conflicting name.
backup_kernel () {
	# Only make kernel backup is so configured.
	if [ $BACKUPKERNEL != yes ]; then
		return 0
	fi

	# Decide which directory name to use for kernel backups.
	backup_kernel_finddir

	# Remove old kernel backup files.  If $BACKUPKERNELDIR was
	# "not ours", backup_kernel_finddir would have exited, so
	# deleting the directory content is as safe as we can make it.
	if [ -d $BASEDIR/$BACKUPKERNELDIR ]; then
		rm -fr $BASEDIR/$BACKUPKERNELDIR
	fi

	# Create directories for backup.
	mkdir -p $BASEDIR/$BACKUPKERNELDIR
	mtree -cdn -p "${BASEDIR}/${KERNELDIR}" | \
	    mtree -Ue -p "${BASEDIR}/${BACKUPKERNELDIR}" > /dev/null

	# Mark the directory as having been created by freebsd-update.
	touch $BASEDIR/$BACKUPKERNELDIR/.freebsd-update
	if [ $? -ne 0 ]; then
		echo "Could not create kernel backup directory"
		exit 1
	fi

	# Disable pathname expansion to be sure *.symbols is not
	# expanded.
	set -f

	# Use find to ignore symbol files, unless disabled by user.
	if [ $BACKUPKERNELSYMBOLFILES = yes ]; then
		FINDFILTER=""
	else
		FINDFILTER=-"a ! -name *.symbols"
	fi

	# Backup all the kernel files using hardlinks.
	(cd ${BASEDIR}/${KERNELDIR} && find . -type f $FINDFILTER -exec \
	    cp -pl '{}' ${BASEDIR}/${BACKUPKERNELDIR}/'{}' \;)

	# Re-enable patchname expansion.
	set +f
}

# Install new files
install_from_index () {
	# First pass: Do everything apart from setting file flags.  We
	# can't set flags yet, because schg inhibits hard linking.
	sort -k 1,1 -t '|' $1 |
	    tr '|' ' ' |
	    while read FPATH TYPE OWNER GROUP PERM FLAGS HASH LINK; do
		case ${TYPE} in
		d)
			# Create a directory
			install -d -o ${OWNER} -g ${GROUP}		\
			    -m ${PERM} ${BASEDIR}/${FPATH}
			;;
		f)
			if [ -z "${LINK}" ]; then
				# Create a file, without setting flags.
				gunzip < files/${HASH}.gz > ${HASH}
				install -S -o ${OWNER} -g ${GROUP}	\
				    -m ${PERM} ${HASH} ${BASEDIR}/${FPATH}
				rm ${HASH}
			else
				# Create a hard link.
				ln -f ${BASEDIR}/${LINK} ${BASEDIR}/${FPATH}
			fi
			;;
		L)
			# Create a symlink
			ln -sfh ${HASH} ${BASEDIR}/${FPATH}
			;;
		esac
	    done

	# Perform a second pass, adding file flags.
	tr '|' ' ' < $1 |
	    while read FPATH TYPE OWNER GROUP PERM FLAGS HASH LINK; do
		if [ ${TYPE} = "f" ] &&
		    ! [ ${FLAGS} = "0" ]; then
			chflags ${FLAGS} ${BASEDIR}/${FPATH}
		fi
	    done
}

# Remove files which we want to delete
install_delete () {
	# Generate list of new files
	cut -f 1 -d '|' < $2 |
	    sort > newfiles

	# Generate subindex of old files we want to nuke
	sort -k 1,1 -t '|' $1 |
	    join -t '|' -v 1 - newfiles |
	    sort -r -k 1,1 -t '|' |
	    cut -f 1,2 -d '|' |
	    tr '|' ' ' > killfiles

	# Remove the offending bits
	while read FPATH TYPE; do
		case ${TYPE} in
		d)
			rmdir ${BASEDIR}/${FPATH}
			;;
		f)
			rm ${BASEDIR}/${FPATH}
			;;
		L)
			rm ${BASEDIR}/${FPATH}
			;;
		esac
	done < killfiles

	# Clean up
	rm newfiles killfiles
}

# Install new files, delete old files, and update linker.hints
install_files () {
	# If we haven't already dealt with the kernel, deal with it.
	if ! [ -f $1/kerneldone ]; then
		grep -E '^/boot/' $1/INDEX-OLD > INDEX-OLD
		grep -E '^/boot/' $1/INDEX-NEW > INDEX-NEW

		# Backup current kernel before installing a new one
		backup_kernel || return 1

		# Install new files
		install_from_index INDEX-NEW || return 1

		# Remove files which need to be deleted
		install_delete INDEX-OLD INDEX-NEW || return 1

		# Update linker.hints if necessary
		if [ -s INDEX-OLD -o -s INDEX-NEW ]; then
			kldxref -R ${BASEDIR}/boot/ 2>/dev/null
		fi

		# We've finished updating the kernel.
		touch $1/kerneldone

		# Do we need to ask for a reboot now?
		if [ -f $1/kernelfirst ] &&
		    [ -s INDEX-OLD -o -s INDEX-NEW ]; then
			cat <<-EOF

Kernel updates have been installed.  Please reboot and run
"$0 install" again to finish installing updates.
			EOF
			exit 0
		fi
	fi

	# If we haven't already dealt with the world, deal with it.
	if ! [ -f $1/worlddone ]; then
		# Create any necessary directories first
		grep -vE '^/boot/' $1/INDEX-NEW |
		    grep -E '^[^|]+\|d\|' > INDEX-NEW
		install_from_index INDEX-NEW || return 1

		# Install new runtime linker
		grep -vE '^/boot/' $1/INDEX-NEW |
		    grep -vE '^[^|]+\|d\|' |
		    grep -E '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' > INDEX-NEW
		install_from_index INDEX-NEW || return 1

		# Install new shared libraries next
		grep -vE '^/boot/' $1/INDEX-NEW |
		    grep -vE '^[^|]+\|d\|' |
		    grep -vE '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' |
		    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-NEW
		install_from_index INDEX-NEW || return 1

		# Deal with everything else
		grep -vE '^/boot/' $1/INDEX-OLD |
		    grep -vE '^[^|]+\|d\|' |
		    grep -vE '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' |
		    grep -vE '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-OLD
		grep -vE '^/boot/' $1/INDEX-NEW |
		    grep -vE '^[^|]+\|d\|' |
		    grep -vE '^/libexec/ld-elf[^|]*\.so\.[0-9]+\|' |
		    grep -vE '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-NEW
		install_from_index INDEX-NEW || return 1
		install_delete INDEX-OLD INDEX-NEW || return 1

		# Rebuild /etc/spwd.db and /etc/pwd.db if necessary.
		if [ ${BASEDIR}/etc/master.passwd -nt ${BASEDIR}/etc/spwd.db ] ||
		    [ ${BASEDIR}/etc/master.passwd -nt ${BASEDIR}/etc/pwd.db ]; then
			pwd_mkdb -d ${BASEDIR}/etc ${BASEDIR}/etc/master.passwd
		fi

		# Rebuild /etc/login.conf.db if necessary.
		if [ ${BASEDIR}/etc/login.conf -nt ${BASEDIR}/etc/login.conf.db ]; then
			cap_mkdb ${BASEDIR}/etc/login.conf
		fi

		# We've finished installing the world and deleting old files
		# which are not shared libraries.
		touch $1/worlddone

		# Do we need to ask the user to portupgrade now?
		grep -vE '^/boot/' $1/INDEX-NEW |
		    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' |
		    cut -f 1 -d '|' |
		    sort > newfiles
		if grep -vE '^/boot/' $1/INDEX-OLD |
		    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' |
		    cut -f 1 -d '|' |
		    sort |
		    join -v 1 - newfiles |
		    grep -q .; then
			cat <<-EOF

Completing this upgrade requires removing old shared object files.
Please rebuild all installed 3rd party software (e.g., programs
installed from the ports tree) and then run "$0 install"
again to finish installing updates.
			EOF
			rm newfiles
			exit 0
		fi
		rm newfiles
	fi

	# Remove old shared libraries
	grep -vE '^/boot/' $1/INDEX-NEW |
	    grep -vE '^[^|]+\|d\|' |
	    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-NEW
	grep -vE '^/boot/' $1/INDEX-OLD |
	    grep -vE '^[^|]+\|d\|' |
	    grep -E '^[^|]*/lib/[^|]*\.so\.[0-9]+\|' > INDEX-OLD
	install_delete INDEX-OLD INDEX-NEW || return 1

	# Remove old directories
	grep -vE '^/boot/' $1/INDEX-NEW |
	    grep -E '^[^|]+\|d\|' > INDEX-NEW
	grep -vE '^/boot/' $1/INDEX-OLD |
	    grep -E '^[^|]+\|d\|' > INDEX-OLD
	install_delete INDEX-OLD INDEX-NEW || return 1

	# Remove temporary files
	rm INDEX-OLD INDEX-NEW
}

# Rearrange bits to allow the installed updates to be rolled back
install_setup_rollback () {
	# Remove the "reboot after installing kernel", "kernel updated", and
	# "finished installing the world" flags if present -- they are
	# irrelevant when rolling back updates.
	if [ -f ${BDHASH}-install/kernelfirst ]; then
		rm ${BDHASH}-install/kernelfirst
		rm ${BDHASH}-install/kerneldone
	fi
	if [ -f ${BDHASH}-install/worlddone ]; then
		rm ${BDHASH}-install/worlddone
	fi

	if [ -L ${BDHASH}-rollback ]; then
		mv ${BDHASH}-rollback ${BDHASH}-install/rollback
	fi

	mv ${BDHASH}-install ${BDHASH}-rollback
}

# Actually install updates
install_run () {
	echo -n "Installing updates..."

	# Make sure we have all the files we should have
	install_verify ${BDHASH}-install/INDEX-OLD	\
	    ${BDHASH}-install/INDEX-NEW || return 1

	# Remove system immutable flag from files
	install_unschg ${BDHASH}-install/INDEX-OLD	\
	    ${BDHASH}-install/INDEX-NEW || return 1

	# Install new files, delete old files, and update linker.hints
	install_files ${BDHASH}-install || return 1

	# Rearrange bits to allow the installed updates to be rolled back
	install_setup_rollback

	echo " done."
}

# Rearrange bits to allow the previous set of updates to be rolled back next.
rollback_setup_rollback () {
	if [ -L ${BDHASH}-rollback/rollback ]; then
		mv ${BDHASH}-rollback/rollback rollback-tmp
		rm -r ${BDHASH}-rollback/
		rm ${BDHASH}-rollback
		mv rollback-tmp ${BDHASH}-rollback
	else
		rm -r ${BDHASH}-rollback/
		rm ${BDHASH}-rollback
	fi
}

# Install old files, delete new files, and update linker.hints
rollback_files () {
	# Install old shared library files which don't have the same path as
	# a new shared library file.
	grep -vE '^/boot/' $1/INDEX-NEW |
	    grep -E '/lib/.*\.so\.[0-9]+\|' |
	    cut -f 1 -d '|' |
	    sort > INDEX-NEW.libs.flist
	grep -vE '^/boot/' $1/INDEX-OLD |
	    grep -E '/lib/.*\.so\.[0-9]+\|' |
	    sort -k 1,1 -t '|' - |
	    join -t '|' -v 1 - INDEX-NEW.libs.flist > INDEX-OLD
	install_from_index INDEX-OLD || return 1

	# Deal with files which are neither kernel nor shared library
	grep -vE '^/boot/' $1/INDEX-OLD |
	    grep -vE '/lib/.*\.so\.[0-9]+\|' > INDEX-OLD
	grep -vE '^/boot/' $1/INDEX-NEW |
	    grep -vE '/lib/.*\.so\.[0-9]+\|' > INDEX-NEW
	install_from_index INDEX-OLD || return 1
	install_delete INDEX-NEW INDEX-OLD || return 1

	# Install any old shared library files which we didn't install above.
	grep -vE '^/boot/' $1/INDEX-OLD |
	    grep -E '/lib/.*\.so\.[0-9]+\|' |
	    sort -k 1,1 -t '|' - |
	    join -t '|' - INDEX-NEW.libs.flist > INDEX-OLD
	install_from_index INDEX-OLD || return 1

	# Delete unneeded shared library files
	grep -vE '^/boot/' $1/INDEX-OLD |
	    grep -E '/lib/.*\.so\.[0-9]+\|' > INDEX-OLD
	grep -vE '^/boot/' $1/INDEX-NEW |
	    grep -E '/lib/.*\.so\.[0-9]+\|' > INDEX-NEW
	install_delete INDEX-NEW INDEX-OLD || return 1

	# Deal with kernel files
	grep -E '^/boot/' $1/INDEX-OLD > INDEX-OLD
	grep -E '^/boot/' $1/INDEX-NEW > INDEX-NEW
	install_from_index INDEX-OLD || return 1
	install_delete INDEX-NEW INDEX-OLD || return 1
	if [ -s INDEX-OLD -o -s INDEX-NEW ]; then
		kldxref -R /boot/ 2>/dev/null
	fi

	# Remove temporary files
	rm INDEX-OLD INDEX-NEW INDEX-NEW.libs.flist
}

# Actually rollback updates
rollback_run () {
	echo -n "Uninstalling updates..."

	# If there are updates waiting to be installed, remove them; we
	# want the user to re-run 'fetch' after rolling back updates.
	if [ -L ${BDHASH}-install ]; then
		rm -r ${BDHASH}-install/
		rm ${BDHASH}-install
	fi

	# Make sure we have all the files we should have
	install_verify ${BDHASH}-rollback/INDEX-NEW	\
	    ${BDHASH}-rollback/INDEX-OLD || return 1

	# Remove system immutable flag from files
	install_unschg ${BDHASH}-rollback/INDEX-NEW	\
	    ${BDHASH}-rollback/INDEX-OLD || return 1

	# Install old files, delete new files, and update linker.hints
	rollback_files ${BDHASH}-rollback || return 1

	# Remove the rollback directory and the symlink pointing to it; and
	# rearrange bits to allow the previous set of updates to be rolled
	# back next.
	rollback_setup_rollback

	echo " done."
}

# Compare INDEX-ALL and INDEX-PRESENT and print warnings about differences.
IDS_compare () {
	# Get all the lines which mismatch in something other than file
	# flags.  We ignore file flags because sysinstall doesn't seem to
	# set them when it installs FreeBSD; warning about these adds a
	# very large amount of noise.
	cut -f 1-5,7-8 -d '|' $1 > $1.noflags
	sort -k 1,1 -t '|' $1.noflags > $1.sorted
	cut -f 1-5,7-8 -d '|' $2 |
	    comm -13 $1.noflags - |
	    fgrep -v '|-|||||' |
	    sort -k 1,1 -t '|' |
	    join -t '|' $1.sorted - > INDEX-NOTMATCHING

	# Ignore files which match IDSIGNOREPATHS.
	for X in ${IDSIGNOREPATHS}; do
		grep -E "^${X}" INDEX-NOTMATCHING
	done |
	    sort -u |
	    comm -13 - INDEX-NOTMATCHING > INDEX-NOTMATCHING.tmp
	mv INDEX-NOTMATCHING.tmp INDEX-NOTMATCHING

	# Go through the lines and print warnings.
	while read LINE; do
		FPATH=`echo "${LINE}" | cut -f 1 -d '|'`
		TYPE=`echo "${LINE}" | cut -f 2 -d '|'`
		OWNER=`echo "${LINE}" | cut -f 3 -d '|'`
		GROUP=`echo "${LINE}" | cut -f 4 -d '|'`
		PERM=`echo "${LINE}" | cut -f 5 -d '|'`
		HASH=`echo "${LINE}" | cut -f 6 -d '|'`
		LINK=`echo "${LINE}" | cut -f 7 -d '|'`
		P_TYPE=`echo "${LINE}" | cut -f 8 -d '|'`
		P_OWNER=`echo "${LINE}" | cut -f 9 -d '|'`
		P_GROUP=`echo "${LINE}" | cut -f 10 -d '|'`
		P_PERM=`echo "${LINE}" | cut -f 11 -d '|'`
		P_HASH=`echo "${LINE}" | cut -f 12 -d '|'`
		P_LINK=`echo "${LINE}" | cut -f 13 -d '|'`

		# Warn about different object types.
		if ! [ "${TYPE}" = "${P_TYPE}" ]; then
			echo -n "${FPATH} is a "
			case "${P_TYPE}" in
			f)	echo -n "regular file, "
				;;
			d)	echo -n "directory, "
				;;
			L)	echo -n "symlink, "
				;;
			esac
			echo -n "but should be a "
			case "${TYPE}" in
			f)	echo -n "regular file."
				;;
			d)	echo -n "directory."
				;;
			L)	echo -n "symlink."
				;;
			esac
			echo

			# Skip other tests, since they don't make sense if
			# we're comparing different object types.
			continue
		fi

		# Warn about different owners.
		if ! [ "${OWNER}" = "${P_OWNER}" ]; then
			echo -n "${FPATH} is owned by user id ${P_OWNER}, "
			echo "but should be owned by user id ${OWNER}."
		fi

		# Warn about different groups.
		if ! [ "${GROUP}" = "${P_GROUP}" ]; then
			echo -n "${FPATH} is owned by group id ${P_GROUP}, "
			echo "but should be owned by group id ${GROUP}."
		fi

		# Warn about different permissions.  We do not warn about
		# different permissions on symlinks, since some archivers
		# don't extract symlink permissions correctly and they are
		# ignored anyway.
		if ! [ "${PERM}" = "${P_PERM}" ] &&
		    ! [ "${TYPE}" = "L" ]; then
			echo -n "${FPATH} has ${P_PERM} permissions, "
			echo "but should have ${PERM} permissions."
		fi

		# Warn about different file hashes / symlink destinations.
		if ! [ "${HASH}" = "${P_HASH}" ]; then
			if [ "${TYPE}" = "L" ]; then
				echo -n "${FPATH} is a symlink to ${P_HASH}, "
				echo "but should be a symlink to ${HASH}."
			fi
			if [ "${TYPE}" = "f" ]; then
				echo -n "${FPATH} has SHA256 hash ${P_HASH}, "
				echo "but should have SHA256 hash ${HASH}."
			fi
		fi

		# We don't warn about different hard links, since some
		# some archivers break hard links, and as long as the
		# underlying data is correct they really don't matter.
	done < INDEX-NOTMATCHING

	# Clean up
	rm $1 $1.noflags $1.sorted $2 INDEX-NOTMATCHING
}

# Do the work involved in comparing the system to a "known good" index
IDS_run () {
	workdir_init || return 1

	# Prepare the mirror list.
	fetch_pick_server_init && fetch_pick_server

	# Try to fetch the public key until we run out of servers.
	while ! fetch_key; do
		fetch_pick_server || return 1
	done
 
	# Try to fetch the metadata index signature ("tag") until we run
	# out of available servers; and sanity check the downloaded tag.
	while ! fetch_tag; do
		fetch_pick_server || return 1
	done
	fetch_tagsanity || return 1

	# Fetch INDEX-OLD and INDEX-ALL.
	fetch_metadata INDEX-OLD INDEX-ALL || return 1

	# Generate filtered INDEX-OLD and INDEX-ALL files containing only
	# the components we want and without anything marked as "Ignore".
	fetch_filter_metadata INDEX-OLD || return 1
	fetch_filter_metadata INDEX-ALL || return 1

	# Merge the INDEX-OLD and INDEX-ALL files into INDEX-ALL.
	sort INDEX-OLD INDEX-ALL > INDEX-ALL.tmp
	mv INDEX-ALL.tmp INDEX-ALL
	rm INDEX-OLD

	# Translate /boot/${KERNCONF} to ${KERNELDIR}
	fetch_filter_kernel_names INDEX-ALL ${KERNCONF}

	# Inspect the system and generate an INDEX-PRESENT file.
	fetch_inspect_system INDEX-ALL INDEX-PRESENT /dev/null || return 1

	# Compare INDEX-ALL and INDEX-PRESENT and print warnings about any
	# differences.
	IDS_compare INDEX-ALL INDEX-PRESENT
}

#### Main functions -- call parameter-handling and core functions

# Using the command line, configuration file, and defaults,
# set all the parameters which are needed later.
get_params () {
	init_params
	parse_cmdline $@
	parse_conffile
	default_params
}

# Fetch command.  Make sure that we're being called
# interactively, then run fetch_check_params and fetch_run
cmd_fetch () {
	if [ ! -t 0 ]; then
		echo -n "`basename $0` fetch should not "
		echo "be run non-interactively."
		echo "Run `basename $0` cron instead."
		exit 1
	fi
	fetch_check_params
	fetch_run || exit 1
}

# Cron command.  Make sure the parameters are sensible; wait
# rand(3600) seconds; then fetch updates.  While fetching updates,
# send output to a temporary file; only print that file if the
# fetching failed.
cmd_cron () {
	fetch_check_params
	sleep `jot -r 1 0 3600`

	TMPFILE=`mktemp /tmp/freebsd-update.XXXXXX` || exit 1
	if ! fetch_run >> ${TMPFILE} ||
	    ! grep -q "No updates needed" ${TMPFILE} ||
	    [ ${VERBOSELEVEL} = "debug" ]; then
		mail -s "`hostname` security updates" ${MAILTO} < ${TMPFILE}
	fi

	rm ${TMPFILE}
}

# Fetch files for upgrading to a new release.
cmd_upgrade () {
	upgrade_check_params
	upgrade_run || exit 1
}

# Install downloaded updates.
cmd_install () {
	install_check_params
	install_run || exit 1
}

# Rollback most recently installed updates.
cmd_rollback () {
	rollback_check_params
	rollback_run || exit 1
}

# Compare system against a "known good" index.
cmd_IDS () {
	IDS_check_params
	IDS_run || exit 1
}

#### Entry point

# Make sure we find utilities from the base system
export PATH=/sbin:/bin:/usr/sbin:/usr/bin:${PATH}

# Set a pager if the user doesn't
if [ -z "$PAGER" ]; then
	PAGER=/usr/bin/more
fi

# Set LC_ALL in order to avoid problems with character ranges like [A-Z].
export LC_ALL=C

get_params $@
for COMMAND in ${COMMANDS}; do
	cmd_${COMMAND}
done
OpenPOWER on IntegriCloud