unofficial mirror of emacs-devel@gnu.org 
 help / color / mirror / code / Atom feed
blob cf705ae5dc1472c89444ae0dc6bd4273496059cb 158501 bytes (raw)
name: lisp/gnus/gnus-agent.el 	 # note: path name is non-authoritative(*)

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
 
;;; gnus-agent.el --- unplugged support for Gnus

;; Copyright (C) 1997-2020 Free Software Foundation, Inc.

;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
;; This file is part of GNU Emacs.

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

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

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

;;; Commentary:

;;; Code:

(require 'gnus)
(require 'gnus-cache)
(require 'nnmail)
(require 'nnvirtual)
(require 'gnus-sum)
(require 'gnus-score)
(require 'gnus-srvr)
(require 'gnus-util)
(require 'timer)
(eval-when-compile (require 'cl-lib))

(autoload 'gnus-server-update-server "gnus-srvr")
(autoload 'gnus-agent-customize-category "gnus-cus")

(defcustom gnus-agent-directory (nnheader-concat gnus-directory "agent/")
  "Where the Gnus agent will store its files."
  :group 'gnus-agent
  :type 'directory)

(defcustom gnus-agent-plugged-hook nil
  "Hook run when plugging into the network."
  :group 'gnus-agent
  :type 'hook)

(defcustom gnus-agent-unplugged-hook nil
  "Hook run when unplugging from the network."
  :group 'gnus-agent
  :type 'hook)

(defcustom gnus-agent-fetched-hook nil
  "Hook run when finished fetching articles."
  :version "22.1"
  :group 'gnus-agent
  :type 'hook)

(defcustom gnus-agent-handle-level gnus-level-subscribed
  "Groups on levels higher than this variable will be ignored by the Agent."
  :group 'gnus-agent
  :type 'integer)

(defcustom gnus-agent-expire-days 7
  "Read articles older than this will be expired.
If you wish to disable Agent expiring, see `gnus-agent-enable-expiration'."
  :group 'gnus-agent
  :type '(number :tag "days"))

(defcustom gnus-agent-expire-all nil
  "If non-nil, also expire unread, ticked and dormant articles.
If nil, only read articles will be expired."
  :group 'gnus-agent
  :type 'boolean)

(defcustom gnus-agent-group-mode-hook nil
  "Hook run in Agent group minor modes."
  :group 'gnus-agent
  :type 'hook)

(defcustom gnus-agent-summary-mode-hook nil
  "Hook run in Agent summary minor modes."
  :group 'gnus-agent
  :type 'hook)

(defcustom gnus-agent-server-mode-hook nil
  "Hook run in Agent summary minor modes."
  :group 'gnus-agent
  :type 'hook)

(defcustom gnus-agent-confirmation-function 'y-or-n-p
  "Function to confirm when error happens."
  :version "21.1"
  :group 'gnus-agent
  :type 'function)

(defcustom gnus-agent-synchronize-flags nil
  "Indicate if flags are synchronized when you plug in.
If this is `ask' the hook will query the user."
  ;; If the default switches to something else than nil, then the function
  ;; should be fixed not be exceedingly slow.  See 2005-09-20 ChangeLog entry.
  :version "21.1"
  :type '(choice (const :tag "Always" t)
		 (const :tag "Never" nil)
		 (const :tag "Ask" ask))
  :group 'gnus-agent)

(defcustom gnus-agent-go-online 'ask
  "Indicate if offline servers go online when you plug in.
If this is `ask' the hook will query the user."
  :version "21.3"
  :type '(choice (const :tag "Always" t)
		 (const :tag "Never" nil)
		 (const :tag "Ask" ask))
  :group 'gnus-agent)

(defcustom gnus-agent-mark-unread-after-downloaded t
  "Indicate whether to mark articles unread after downloaded."
  :version "21.1"
  :type 'boolean
  :group 'gnus-agent)

(defcustom gnus-agent-download-marks '(download)
  "Marks for downloading."
  :version "21.1"
  :type '(repeat (symbol :tag "Mark"))
  :group 'gnus-agent)

(defcustom gnus-agent-consider-all-articles nil
  "When non-nil, the agent will let the agent predicate decide
whether articles need to be downloaded or not, for all articles.  When
nil, the default, the agent will only let the predicate decide
whether unread articles are downloaded or not.  If you enable this,
groups with large active ranges may open slower and you may also want
to look into the agent expiry settings to block the expiration of
read articles as they would just be downloaded again."
  :version "22.1"
  :type 'boolean
  :group 'gnus-agent)

(defcustom gnus-agent-max-fetch-size 10000000 ;; 10 Mb
  "Chunk size for `gnus-agent-fetch-session'.
The function will split its article fetches into chunks smaller than
this limit."
  :version "22.1"
  :group 'gnus-agent
  :type 'integer)

(defcustom gnus-agent-enable-expiration 'ENABLE
  "The default expiration state for each group.
When set to ENABLE, the default, `gnus-agent-expire' will expire old
contents from a group's local storage.  This value may be overridden
to disable expiration in specific categories, topics, and groups.  Of
course, you could change gnus-agent-enable-expiration to DISABLE then
enable expiration per categories, topics, and groups."
  :version "22.1"
  :group 'gnus-agent
  :type '(radio (const :format "Enable " ENABLE)
                (const :format "Disable " DISABLE)))

(defcustom gnus-agent-expire-unagentized-dirs t
  "Whether expiration should expire in unagentized directories.
Have gnus-agent-expire scan the directories under
\(gnus-agent-directory) for groups that are no longer agentized.
When found, offer to remove them."
  :version "22.1"
  :type 'boolean
  :group 'gnus-agent)

(defcustom gnus-agent-auto-agentize-methods nil
  "Initially, all servers from these methods are agentized.
The user may remove or add servers using the Server buffer.
See Info node `(gnus)Server Buffer' and Info node `(gnus)Agent Variables'."
  :version "22.1"
  :type '(repeat symbol)
  :group 'gnus-agent)

(defcustom gnus-agent-queue-mail t
  "Whether and when outgoing mail should be queued by the agent.
When `always', always queue outgoing mail.  When nil, never
queue.  Otherwise, queue if and only if unplugged."
  :version "22.1"
  :group 'gnus-agent
  :type '(radio (const :format "Always" always)
		(const :format "Never" nil)
		(const :format "When unplugged" t)))

(defcustom gnus-agent-prompt-send-queue nil
  "If non-nil, `gnus-group-send-queue' will prompt if called when unplugged."
  :version "22.1"
  :group 'gnus-agent
  :type 'boolean)

(defcustom gnus-agent-article-alist-save-format 1
  "Indicates whether to use compression(2), versus no
compression(1), when writing agentview files.  The compressed
files do save space but load times are 6-7 times higher.  A group
must be opened then closed for the agentview to be updated using
the new format."
  ;; Wouldn't symbols instead numbers be nicer?  --rsteib
  :version "22.1"
  :group 'gnus-agent
  :type '(radio (const :format "Compressed" 2)
		(const :format "Uncompressed" 1)))

;;; Internal variables

(defvar gnus-agent-history-buffers nil)
(defvar gnus-agent-buffer-alist nil)
(defvar gnus-agent-article-alist nil
  "An assoc list identifying the articles whose headers have been fetched.
If successfully fetched, these headers will be stored in the group's overview
file.  The key of each assoc pair is the article ID, the value of each assoc
pair is a flag indicating whether the identified article has been downloaded
\(gnus-agent-fetch-articles sets the value to the day of the download).
NOTES:
1) The last element of this list can not be expired as some
   routines (for example, get-agent-fetch-headers) use the last
   value to track which articles have had their headers retrieved.
2) The function `gnus-agent-regenerate' may destructively modify the value.")
(defvar gnus-agent-group-alist nil)
(defvar gnus-category-alist nil)
(defvar gnus-agent-current-history nil)
(defvar gnus-agent-overview-buffer nil)
(defvar gnus-category-predicate-cache nil)
(defvar gnus-category-group-cache nil)
(defvar gnus-agent-spam-hashtb nil
  "Cache of message subjects for spam messages.
Actually a hash table holding subjects mapped to t.")
(defvar gnus-agent-file-name nil)
(defvar gnus-agent-file-coding-system 'utf-8-emacs)
(defvar gnus-agent-file-loading-cache nil)
(defvar gnus-agent-total-fetched-hashtb nil)
(defvar gnus-agent-inhibit-update-total-fetched-for nil)
(defvar gnus-agent-need-update-total-fetched-for nil)

;; Dynamic variables
(defvar gnus-headers)
(defvar gnus-score)

;;;
;;; Setup
;;;

(defun gnus-open-agent ()
  (setq gnus-agent t)
  (gnus-agent-read-servers)
  (gnus-category-read)
  (gnus-agent-create-buffer)
  (add-hook 'gnus-group-mode-hook 'gnus-agent-mode)
  (add-hook 'gnus-summary-mode-hook 'gnus-agent-mode)
  (add-hook 'gnus-server-mode-hook 'gnus-agent-mode))

(defun gnus-agent-create-buffer ()
  (if (gnus-buffer-live-p gnus-agent-overview-buffer)
      t
    (setq gnus-agent-overview-buffer
	  (gnus-get-buffer-create " *Gnus agent overview*"))
    (with-current-buffer gnus-agent-overview-buffer
      (mm-enable-multibyte))
    nil))

(gnus-add-shutdown 'gnus-close-agent 'gnus)

(defun gnus-close-agent ()
  (setq gnus-category-predicate-cache nil
	gnus-category-group-cache nil
	gnus-agent-spam-hashtb nil)
  (gnus-kill-buffer gnus-agent-overview-buffer))

;;;
;;; Utility functions
;;;

(defmacro gnus-agent-with-refreshed-group (group &rest body)
  "Performs the body then updates the group's line in the group
buffer.  Automatically blocks multiple updates due to recursion."
  `(prog1 (let ((gnus-agent-inhibit-update-total-fetched-for t)) ,@body)
     (when (and gnus-agent-need-update-total-fetched-for
		(not gnus-agent-inhibit-update-total-fetched-for))
	(with-current-buffer gnus-group-buffer
	  (setq gnus-agent-need-update-total-fetched-for nil)
	  (gnus-group-update-group ,group t)))))

(defun gnus-agent-read-file (file)
  "Load FILE and do a `read' there."
  (with-temp-buffer
    (ignore-errors
      (nnheader-insert-file-contents file)
      (goto-char (point-min))
      (read (current-buffer)))))

(defsubst gnus-agent-method ()
  (concat (symbol-name (car gnus-command-method)) "/"
	  (if (equal (cadr gnus-command-method) "")
	      "unnamed"
	    (cadr gnus-command-method))))

(defsubst gnus-agent-directory ()
  "The name of the Gnus agent directory."
  (nnheader-concat gnus-agent-directory
		   (nnheader-translate-file-chars (gnus-agent-method)) "/"))

(defun gnus-agent-lib-file (file)
  "The full name of the Gnus agent library FILE."
  (expand-file-name file
		    (file-name-as-directory
		     (expand-file-name "agent.lib" (gnus-agent-directory)))))

(defun gnus-agent-cat-set-property (category property value)
  (if value
      (setcdr (or (assq property category)
                  (let ((cell (cons property nil)))
                    (setcdr category (cons cell (cdr category)))
                    cell))
              value)
    (let ((category category))
      (while (cond ((eq property (caadr category))
                    (setcdr category (cddr category))
                    nil)
                   (t
                    (setq category (cdr category)))))))
  category)

(eval-when-compile
  (defmacro gnus-agent-cat-defaccessor (name prop-name)
    "Define accessor and setter methods for manipulating a list of the form
\(NAME (PROPERTY1 VALUE1) ... (PROPERTY_N VALUE_N)).
Given the call (gnus-agent-cat-defaccessor func PROPERTY1), the list may be
manipulated as follows:
  (func LIST): Returns VALUE1
  (setf (func LIST) NEW_VALUE1): Replaces VALUE1 with NEW_VALUE1."
    `(progn (defmacro ,name (category)
              (list 'cdr (list 'assq '',prop-name category)))

	    (gv-define-setter ,name (value category)
	      (list 'gnus-agent-cat-set-property
		    category '',prop-name value))))
  )

(defmacro gnus-agent-cat-name (category)
  `(car ,category))

(gnus-agent-cat-defaccessor
 gnus-agent-cat-days-until-old             agent-days-until-old)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-enable-expiration          agent-enable-expiration)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-groups                     agent-groups)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-high-score                 agent-high-score)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-length-when-long           agent-long-article)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-length-when-short          agent-short-article)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-low-score                  agent-low-score)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-predicate                  agent-predicate)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-score-file                 agent-score)
(gnus-agent-cat-defaccessor
 gnus-agent-cat-enable-undownloaded-faces  agent-enable-undownloaded-faces)

(gv-define-simple-setter gnus-agent-cat-groups gnus-agent-set-cat-groups)

(defun gnus-agent-set-cat-groups (category groups)
  (unless (eq groups 'ignore)
    (let ((new-g groups)
          (old-g (gnus-agent-cat-groups category)))
      (cond ((eq new-g old-g)
             ;; gnus-agent-add-group is fiddling with the group
             ;; list. Still, Im done.
             nil
             )
            ((eq new-g (cdr old-g))
             ;; gnus-agent-add-group is fiddling with the group list
             (setcdr (or (assq 'agent-groups category)
                         (let ((cell (cons 'agent-groups nil)))
                           (setcdr category (cons cell (cdr category)))
                           cell))
                     new-g))
            (t
             (let ((groups groups))
               (while groups
                 (let* ((group        (pop groups))
                        (old-category (gnus-group-category group)))
                   (if (eq category old-category)
                       nil
                     (setf (gnus-agent-cat-groups old-category)
                           (delete group (gnus-agent-cat-groups
                                          old-category))))))
               ;; Purge cache as preceding loop invalidated it.
               (setq gnus-category-group-cache nil))

             (setcdr (or (assq 'agent-groups category)
                         (let ((cell (cons 'agent-groups nil)))
                           (setcdr category (cons cell (cdr category)))
                           cell))
                     groups))))))

(defsubst gnus-agent-cat-make (name &optional default-agent-predicate)
  (list name `(agent-predicate . ,(or default-agent-predicate 'false))))

(defun gnus-agent-read-group ()
  "Read a group name in the minibuffer, with completion."
  (let ((def (or (gnus-group-group-name) gnus-newsgroup-name)))
    (gnus-group-completing-read nil nil t nil nil def)))

;;; Fetching setup functions.

(defun gnus-agent-start-fetch ()
  "Initialize data structures for efficient fetching."
  (gnus-agent-create-buffer))

(defun gnus-agent-stop-fetch ()
  "Save all data structures and clean up."
  (setq gnus-agent-spam-hashtb nil)
  (with-current-buffer nntp-server-buffer
    (widen)))

(defmacro gnus-agent-with-fetch (&rest forms)
  "Do FORMS safely."
  `(unwind-protect
       (let ((gnus-agent-fetching t))
	 (gnus-agent-start-fetch)
	 ,@forms)
     (gnus-agent-stop-fetch)))

(put 'gnus-agent-with-fetch 'lisp-indent-function 0)
(put 'gnus-agent-with-fetch 'edebug-form-spec '(body))

(defmacro gnus-agent-append-to-list (tail value)
  `(setq ,tail (setcdr ,tail (cons ,value nil))))

(defmacro gnus-agent-message (level &rest args)
  `(if (<= ,level gnus-verbose)
       (message ,@args)))

;;;
;;; Mode infestation
;;;

(defvar gnus-agent-mode-hook nil
  "Hook run when installing agent mode.")

(defvar gnus-agent-mode nil)
(defvar gnus-agent-mode-status '(gnus-agent-mode " Plugged"))

(defun gnus-agent-mode ()
  "Minor mode for providing agent support in Gnus buffers."
  (let* ((buffer (progn (string-match "^gnus-\\(.*\\)-mode$"
				      (symbol-name major-mode))
			(match-string 1 (symbol-name major-mode))))
	 (mode (intern (format "gnus-agent-%s-mode" buffer))))
    (set (make-local-variable 'gnus-agent-mode) t)
    (set mode nil)
    (set (make-local-variable mode) t)
    ;; Set up the menu.
    (when (gnus-visual-p 'agent-menu 'menu)
      (funcall (intern (format "gnus-agent-%s-make-menu-bar" buffer))))
    (unless (assq mode minor-mode-alist)
      (push (cons mode (cdr gnus-agent-mode-status)) minor-mode-alist))
    (unless (assq mode minor-mode-map-alist)
      (push (cons mode (symbol-value (intern (format "gnus-agent-%s-mode-map"
						     buffer))))
	    minor-mode-map-alist))
    (when (derived-mode-p 'gnus-group-mode)
      (let ((init-plugged gnus-plugged)
            (gnus-agent-go-online nil))
        ;; g-a-t-p does nothing when gnus-plugged isn't changed.
        ;; Therefore, make certain that the current value does not
        ;; match the desired initial value.
        (setq gnus-plugged :unknown)
        (gnus-agent-toggle-plugged init-plugged)))
    (gnus-run-hooks 'gnus-agent-mode-hook
		    (intern (format "gnus-agent-%s-mode-hook" buffer)))))

(defvar gnus-agent-group-mode-map (make-sparse-keymap))
(gnus-define-keys gnus-agent-group-mode-map
  "Ju" gnus-agent-fetch-groups
  "Jc" gnus-enter-category-buffer
  "Jj" gnus-agent-toggle-plugged
  "Js" gnus-agent-fetch-session
  "JY" gnus-agent-synchronize-flags
  "JS" gnus-group-send-queue
  "Ja" gnus-agent-add-group
  "Jr" gnus-agent-remove-group
  "Jo" gnus-agent-toggle-group-plugged)

(defun gnus-agent-group-make-menu-bar ()
  (unless (boundp 'gnus-agent-group-menu)
    (easy-menu-define
     gnus-agent-group-menu gnus-agent-group-mode-map ""
     '("Agent"
       ["Toggle plugged" gnus-agent-toggle-plugged t]
       ["Toggle group plugged" gnus-agent-toggle-group-plugged t]
       ["List categories" gnus-enter-category-buffer t]
       ["Add (current) group to category" gnus-agent-add-group t]
       ["Remove (current) group from category" gnus-agent-remove-group t]
       ["Send queue" gnus-group-send-queue gnus-plugged]
       ("Fetch"
	["All" gnus-agent-fetch-session gnus-plugged]
	["Group" gnus-agent-fetch-group gnus-plugged])
       ["Synchronize flags" gnus-agent-synchronize-flags t]
       ))))

(defvar gnus-agent-summary-mode-map (make-sparse-keymap))
(gnus-define-keys gnus-agent-summary-mode-map
  "Jj" gnus-agent-toggle-plugged
  "Ju" gnus-agent-summary-fetch-group
  "JS" gnus-agent-fetch-group
  "Js" gnus-agent-summary-fetch-series
  "J#" gnus-agent-mark-article
  "J\M-#" gnus-agent-unmark-article
  "@" gnus-agent-toggle-mark
  "Jc" gnus-agent-catchup)

(defun gnus-agent-summary-make-menu-bar ()
  (unless (boundp 'gnus-agent-summary-menu)
    (easy-menu-define
     gnus-agent-summary-menu gnus-agent-summary-mode-map ""
     '("Agent"
       ["Toggle plugged" gnus-agent-toggle-plugged t]
       ["Mark as downloadable" gnus-agent-mark-article t]
       ["Unmark as downloadable" gnus-agent-unmark-article t]
       ["Toggle mark" gnus-agent-toggle-mark t]
       ["Fetch downloadable" gnus-agent-summary-fetch-group t]
       ["Catchup undownloaded" gnus-agent-catchup t]))))

(defvar gnus-agent-server-mode-map (make-sparse-keymap))
(gnus-define-keys gnus-agent-server-mode-map
  "Jj" gnus-agent-toggle-plugged
  "Ja" gnus-agent-add-server
  "Jr" gnus-agent-remove-server)

(defun gnus-agent-server-make-menu-bar ()
  (unless (boundp 'gnus-agent-server-menu)
    (easy-menu-define
     gnus-agent-server-menu gnus-agent-server-mode-map ""
     '("Agent"
       ["Toggle plugged" gnus-agent-toggle-plugged t]
       ["Add" gnus-agent-add-server t]
       ["Remove" gnus-agent-remove-server t]))))

(defun gnus-agent-make-mode-line-string (string mouse-button mouse-func)
  (propertize string 'local-map
	      (make-mode-line-mouse-map mouse-button mouse-func)
	      'mouse-face 'mode-line-highlight))

(defun gnus-agent-toggle-plugged (set-to)
  "Toggle whether Gnus is unplugged or not."
  (interactive (list (not gnus-plugged)))
  (cond ((eq set-to gnus-plugged)
         nil)
        (set-to
         (setq gnus-plugged set-to)
         (gnus-run-hooks 'gnus-agent-plugged-hook)
         (setcar (cdr gnus-agent-mode-status)
                 (gnus-agent-make-mode-line-string " Plugged"
                                                   'mouse-2
                                                   'gnus-agent-toggle-plugged))
         (gnus-agent-go-online gnus-agent-go-online))
        (t
         (gnus-agent-close-connections)
         (setq gnus-plugged set-to)
         (gnus-run-hooks 'gnus-agent-unplugged-hook)
         (setcar (cdr gnus-agent-mode-status)
                 (gnus-agent-make-mode-line-string " Unplugged"
                                                   'mouse-2
                                                   'gnus-agent-toggle-plugged))))
  (set-buffer-modified-p t))

(defmacro gnus-agent-while-plugged (&rest body)
  `(let ((original-gnus-plugged gnus-plugged))
    (unwind-protect
        (progn (gnus-agent-toggle-plugged t)
               ,@body)
      (gnus-agent-toggle-plugged original-gnus-plugged))))

(put 'gnus-agent-while-plugged 'lisp-indent-function 0)
(put 'gnus-agent-while-plugged 'edebug-form-spec '(body))

(defun gnus-agent-close-connections ()
  "Close all methods covered by the Gnus agent."
  (let ((methods (gnus-agent-covered-methods)))
    (while methods
      (gnus-close-server (pop methods)))))

;;;###autoload
(defun gnus-unplugged ()
  "Start Gnus unplugged."
  (interactive)
  (setq gnus-plugged nil)
  (gnus))

;;;###autoload
(defun gnus-plugged ()
  "Start Gnus plugged."
  (interactive)
  (setq gnus-plugged t)
  (gnus))

;;;###autoload
(defun gnus-slave-unplugged (&optional arg)
  "Read news as a slave unplugged."
  (interactive "P")
  (setq gnus-plugged nil)
  (gnus arg nil 'slave))

;;;###autoload
(defun gnus-agentize ()
  "Allow Gnus to be an offline newsreader.

The gnus-agentize function is now called internally by gnus when
gnus-agent is set.  If you wish to avoid calling gnus-agentize,
customize gnus-agent to nil.

This will modify the `gnus-setup-news-hook', and
`message-send-mail-real-function' variables, and install the Gnus agent
minor mode in all Gnus buffers."
  (interactive)
  (gnus-open-agent)
  (setq message-send-mail-real-function 'gnus-agent-send-mail)

  ;; If the servers file doesn't exist, auto-agentize some servers and
  ;; save the servers file so this auto-agentizing isn't invoked
  ;; again.
  (when (and (not (file-exists-p (nnheader-concat
				  gnus-agent-directory "lib/servers")))
	     gnus-agent-auto-agentize-methods)
    (gnus-message 3 "First time agent user, agentizing remote groups...")
    (mapc
     (lambda (server-or-method)
       (let ((method (gnus-server-to-method server-or-method)))
	 (when (memq (car method)
		     gnus-agent-auto-agentize-methods)
	   (push (gnus-method-to-server method)
		 gnus-agent-covered-methods)
	   (setq gnus-agent-method-p-cache nil))))
     (cons gnus-select-method gnus-secondary-select-methods))
    (gnus-agent-write-servers)))

(defun gnus-agent-queue-setup (&optional group-name)
  "Make sure the queue group exists.
Optional arg GROUP-NAME allows another group to be specified."
  (unless (gethash (format "nndraft:%s" (or group-name "queue"))
		   gnus-newsrc-hashtb)
    (gnus-request-create-group (or group-name "queue") '(nndraft ""))
    (let ((gnus-level-default-subscribed 1))
      (gnus-subscribe-group (format "nndraft:%s" (or group-name "queue"))
			    nil '(nndraft "")))
    (gnus-group-set-parameter
     (format "nndraft:%s" (or group-name "queue"))
     'gnus-dummy '((gnus-draft-mode)))))

(defun gnus-agent-send-mail ()
  (if (or (not gnus-agent-queue-mail)
	  (and gnus-plugged (not (eq gnus-agent-queue-mail 'always))))
      (message-multi-smtp-send-mail)
    (goto-char (point-min))
    (re-search-forward
     (concat "^" (regexp-quote mail-header-separator) "\n"))
    (replace-match "\n")
    (gnus-agent-insert-meta-information 'mail)
    (gnus-request-accept-article "nndraft:queue" nil t t)
    (gnus-group-refresh-group "nndraft:queue")))

(defun gnus-agent-insert-meta-information (type &optional method)
  "Insert meta-information into the message that says how it's to be posted.
TYPE can be either `mail' or `news'.  If the latter, then METHOD can
be a select method."
  (save-excursion
    (message-remove-header gnus-agent-meta-information-header)
    (goto-char (point-min))
    (insert gnus-agent-meta-information-header ": "
	    (symbol-name type) " " (format "%S" method)
	    "\n")
    (forward-char -1)
    (while (search-backward "\n" nil t)
      (replace-match "\\n" t t))))

(defun gnus-agent-restore-gcc ()
  "Restore GCC field from saved header."
  (save-excursion
    (goto-char (point-min))
    (while (re-search-forward
	    (concat "^" (regexp-quote gnus-agent-gcc-header) ":") nil t)
      (replace-match "Gcc:" 'fixedcase))))

(defun gnus-agent-any-covered-gcc ()
  (save-restriction
    (message-narrow-to-headers)
    (let* ((gcc (mail-fetch-field "gcc" nil t))
	   (methods (and gcc
			 (mapcar 'gnus-inews-group-method
				 (message-unquote-tokens
				  (message-tokenize-header
				   gcc " ,")))))
	   covered)
      (while (and (not covered) methods)
	(setq covered (gnus-agent-method-p (car methods))
	      methods (cdr methods)))
      covered)))

;;;###autoload
(defun gnus-agent-possibly-save-gcc ()
  "Save GCC if Gnus is unplugged."
  (when (and (not gnus-plugged) (gnus-agent-any-covered-gcc))
    (save-excursion
      (goto-char (point-min))
      (let ((case-fold-search t))
	(while (re-search-forward "^gcc:" nil t)
	  (replace-match (concat gnus-agent-gcc-header ":") 'fixedcase))))))

(defun gnus-agent-possibly-do-gcc ()
  "Do GCC if Gnus is plugged."
  (when (or gnus-plugged (not (gnus-agent-any-covered-gcc)))
    (gnus-inews-do-gcc)))

;;;
;;; Group mode commands
;;;

(defun gnus-agent-fetch-groups (n)
  "Put all new articles in the current groups into the Agent."
  (interactive "P")
  (unless gnus-plugged
    (error "Groups can't be fetched when Gnus is unplugged"))
  (gnus-group-iterate n 'gnus-agent-fetch-group))

(defun gnus-agent-fetch-group (&optional group)
  "Put all new articles in GROUP into the Agent."
  (interactive (list (gnus-group-group-name)))
  (setq group (or group gnus-newsgroup-name))
  (unless group
    (error "No group on the current line"))
  (if (not (gnus-agent-group-covered-p group))
      (message "%s isn't covered by the agent" group)
    (gnus-agent-while-plugged
      (let ((gnus-command-method (gnus-find-method-for-group group)))
	(gnus-agent-with-fetch
	  (gnus-agent-fetch-group-1 group gnus-command-method)
	  (gnus-message 5 "Fetching %s...done" group))))))

(defun gnus-agent-add-group (category arg)
  "Add the current group to an agent category."
  (interactive
   (list
    (intern
     (gnus-completing-read
      "Add to category"
      (mapcar (lambda (cat) (symbol-name (car cat)))
	      gnus-category-alist)
      t))
    current-prefix-arg))
  (let ((cat (assq category gnus-category-alist))
	c groups)
    (gnus-group-iterate arg
      (lambda (group)
	(when (gnus-agent-cat-groups (setq c (gnus-group-category group)))
	  (setf (gnus-agent-cat-groups c)
                (delete group (gnus-agent-cat-groups c))))
	(push group groups)))
    (setf (gnus-agent-cat-groups cat)
          (nconc (gnus-agent-cat-groups cat) groups))
    (gnus-category-write)))

(defun gnus-agent-remove-group (arg)
  "Remove the current group from its agent category, if any."
  (interactive "P")
  (let (c)
    (gnus-group-iterate arg
      (lambda (group)
	(when (gnus-agent-cat-groups (setq c (gnus-group-category group)))
	  (setf (gnus-agent-cat-groups c)
                (delete group (gnus-agent-cat-groups c))))))
    (gnus-category-write)))

(defun gnus-agent-synchronize-flags ()
  "Synchronize unplugged flags with servers."
  (interactive)
  (save-excursion
    (dolist (gnus-command-method (gnus-agent-covered-methods))
      (when (file-exists-p (gnus-agent-lib-file "flags"))
	(gnus-agent-synchronize-flags-server gnus-command-method)))))

(defun gnus-agent-possibly-synchronize-flags ()
  "Synchronize flags according to `gnus-agent-synchronize-flags'."
  (interactive)
  (save-excursion
    (dolist (gnus-command-method (gnus-agent-covered-methods))
      (when (eq (gnus-server-status gnus-command-method) 'ok)
	(gnus-agent-possibly-synchronize-flags-server gnus-command-method)))))

(defun gnus-agent-synchronize-flags-server (method)
  "Synchronize flags set when unplugged for server."
  (let ((gnus-command-method method)
	(gnus-agent nil))
    (when (file-exists-p (gnus-agent-lib-file "flags"))
      (set-buffer (get-buffer-create " *Gnus Agent flag synchronize*"))
      (erase-buffer)
      (nnheader-insert-file-contents (gnus-agent-lib-file "flags"))
      (cond ((null gnus-plugged)
	     (gnus-message
	      1 "You must be plugged to synchronize flags with server %s"
	      (nth 1 gnus-command-method)))
	    ((null (gnus-check-server gnus-command-method))
	     (gnus-message
	      1 "Couldn't open server %s" (nth 1 gnus-command-method)))
	    (t
	     (condition-case err
		 (while t
		   (let ((bgn (point)))
		     (eval (read (current-buffer)))
		     (delete-region bgn (point))))
	       (end-of-file
		(delete-file (gnus-agent-lib-file "flags")))
	       (error
		(let ((file (gnus-agent-lib-file "flags")))
		  (write-region (point-min) (point-max)
				(gnus-agent-lib-file "flags") nil 'silent)
		  (error "Couldn't set flags from file %s due to %s"
			 file (error-message-string err)))))))
      (kill-buffer nil))))

(defun gnus-agent-possibly-synchronize-flags-server (method)
  "Synchronize flags for server according to `gnus-agent-synchronize-flags'."
  (when (and (file-exists-p (gnus-agent-lib-file "flags"))
	     (or (and gnus-agent-synchronize-flags
		      (not (eq gnus-agent-synchronize-flags 'ask)))
		 (and (eq gnus-agent-synchronize-flags 'ask)
		      (gnus-y-or-n-p
		       (format-message
			"Synchronize flags on server `%s'? "
			(cadr method))))))
    (gnus-agent-synchronize-flags-server method)))

;;;###autoload
(defun gnus-agent-rename-group (old-group new-group)
  "Rename fully-qualified OLD-GROUP as NEW-GROUP.
Always updates the agent, even when disabled, as the old agent
files would corrupt gnus when the agent was next enabled.
Depends upon the caller to determine whether group renaming is
supported."
  (let* ((old-command-method (gnus-find-method-for-group old-group))
	 (old-path           (directory-file-name
			      (let ((gnus-command-method old-command-method))
				(gnus-agent-group-pathname old-group))))
	 (new-command-method (gnus-find-method-for-group new-group))
	 (new-path           (directory-file-name
			      (let ((gnus-command-method new-command-method))
				(gnus-agent-group-pathname new-group))))
	 (file-name-coding-system nnmail-pathname-coding-system))
    (gnus-rename-file old-path new-path t)

    (let* ((old-real-group (gnus-group-real-name old-group))
	   (new-real-group (gnus-group-real-name new-group))
	   (old-active (gnus-agent-get-group-info old-command-method old-real-group)))
      (gnus-agent-save-group-info old-command-method old-real-group nil)
      (gnus-agent-save-group-info new-command-method new-real-group old-active)

      (let ((old-local (gnus-agent-get-local old-group
					     old-real-group old-command-method)))
	(gnus-agent-set-local old-group
			      nil nil
			      old-real-group old-command-method)
	(gnus-agent-set-local new-group
			      (car old-local) (cdr old-local)
			      new-real-group new-command-method)))))

;;;###autoload
(defun gnus-agent-delete-group (group)
  "Delete fully-qualified GROUP.
Always updates the agent, even when disabled, as the old agent
files would corrupt gnus when the agent was next enabled.
Depends upon the caller to determine whether group deletion is
supported."
  (let* ((command-method (gnus-find-method-for-group group))
	 (path           (directory-file-name
			  (let ((gnus-command-method command-method))
			    (gnus-agent-group-pathname group))))
	 (file-name-coding-system nnmail-pathname-coding-system))
    (gnus-delete-directory path)

    (let* ((real-group (gnus-group-real-name group)))
      (gnus-agent-save-group-info command-method real-group nil)
      ;; FIXME: Does gnus-agent-get-local have any useful side-effect?
      (gnus-agent-get-local group real-group command-method)
      (gnus-agent-set-local group
                            nil nil
                            real-group command-method))))

;;;
;;; Server mode commands
;;;

(defun gnus-agent-add-server ()
  "Enroll SERVER in the agent program."
  (interactive)
  (let* ((server       (gnus-server-server-name))
         (named-server (gnus-server-named-server))
         (method       (and server
                            (gnus-server-get-method nil server))))
    (unless server
      (error "No server on the current line"))

    (when (gnus-agent-method-p method)
      (error "Server already in the agent program"))

    (push named-server gnus-agent-covered-methods)

    (setq gnus-agent-method-p-cache nil)
    (gnus-server-update-server server)
    (gnus-agent-write-servers)
    (gnus-message 1 "Entered %s into the Agent" server)))

(defun gnus-agent-remove-server ()
  "Remove SERVER from the agent program."
  (interactive)
  (let* ((server       (gnus-server-server-name))
         (named-server (gnus-server-named-server)))
    (unless server
      (error "No server on the current line"))

    (unless (member named-server gnus-agent-covered-methods)
      (error "Server not in the agent program"))

    (setq gnus-agent-covered-methods
          (delete named-server gnus-agent-covered-methods)
          gnus-agent-method-p-cache nil)

    (gnus-server-update-server server)
    (gnus-agent-write-servers)
    (gnus-message 1 "Removed %s from the agent" server)))

(defun gnus-agent-read-servers ()
  "Read the alist of covered servers."
  (setq gnus-agent-covered-methods
        (gnus-agent-read-file
         (nnheader-concat gnus-agent-directory "lib/servers"))
        gnus-agent-method-p-cache nil)

  ;; I am called so early in start-up that I can not validate server
  ;; names.  When that is the case, I skip the validation.  That is
  ;; alright as the gnus startup code calls the validate methods
  ;; directly.
  (if gnus-server-alist
      (gnus-agent-read-servers-validate)))

(defun gnus-agent-read-servers-validate ()
  (mapcar (lambda (server-or-method)
            (let* ((server (if (stringp server-or-method)
                               server-or-method
                             (gnus-method-to-server server-or-method)))
                   (method (gnus-server-to-method server)))
              (if method
                  (unless (member server gnus-agent-covered-methods)
                    (push server gnus-agent-covered-methods)
                    (setq gnus-agent-method-p-cache nil))
                (gnus-message 8 "Ignoring disappeared server `%s'" server))))
          (prog1 gnus-agent-covered-methods
            (setq gnus-agent-covered-methods nil))))

(defun gnus-agent-read-servers-validate-native (native-method)
  (setq gnus-agent-covered-methods
        (mapcar (lambda (method)
                  (if (or (not method)
                          (equal method native-method))
                      "native"
                    method)) gnus-agent-covered-methods)))

(defun gnus-agent-write-servers ()
  "Write the alist of covered servers."
  (gnus-make-directory (nnheader-concat gnus-agent-directory "lib"))
  (let ((coding-system-for-write nnheader-file-coding-system)
	(file-name-coding-system nnmail-pathname-coding-system))
    (with-temp-file (nnheader-concat gnus-agent-directory "lib/servers")
      (prin1 gnus-agent-covered-methods
	     (current-buffer)))))

;;;
;;; Summary commands
;;;

(defun gnus-agent-mark-article (n &optional unmark)
  "Mark the next N articles as downloadable.
If N is negative, mark backward instead.  If UNMARK is non-nil, remove
the mark instead.  The difference between N and the actual number of
articles marked is returned."
  (interactive "p")
  (let ((backward (< n 0))
	(n (abs n)))
    (while (and
	    (> n 0)
	    (progn
	      (gnus-summary-set-agent-mark
	       (gnus-summary-article-number) unmark)
	      (zerop (gnus-summary-next-subject (if backward -1 1) nil t))))
      (setq n (1- n)))
    (when (/= 0 n)
      (gnus-message 7 "No more articles"))
    (gnus-summary-recenter)
    (gnus-summary-position-point)
    n))

(defun gnus-agent-unmark-article (n)
  "Remove the downloadable mark from the next N articles.
If N is negative, unmark backward instead.  The difference between N and
the actual number of articles unmarked is returned."
  (interactive "p")
  (gnus-agent-mark-article n t))

(defun gnus-agent-toggle-mark (n)
  "Toggle the downloadable mark from the next N articles.
If N is negative, toggle backward instead.  The difference between N and
the actual number of articles toggled is returned."
  (interactive "p")
  (gnus-agent-mark-article n 'toggle))

(defun gnus-summary-set-agent-mark (article &optional unmark)
  "Mark ARTICLE as downloadable.  If UNMARK is nil, article is marked.
When UNMARK is t, the article is unmarked.  For any other value, the
article's mark is toggled."
  (let ((unmark (cond ((eq nil unmark)
		       nil)
		      ((eq t unmark)
		       t)
		      (t
		       (memq article gnus-newsgroup-downloadable)))))
    (when (gnus-summary-goto-subject article nil t)
      (gnus-summary-update-mark
       (if unmark
           (progn
             (setq gnus-newsgroup-downloadable
                   (delq article gnus-newsgroup-downloadable))
             (gnus-article-mark article))
	 (setq gnus-newsgroup-downloadable
	       (gnus-add-to-sorted-list gnus-newsgroup-downloadable article))
	 gnus-downloadable-mark)
       'unread))))

;;;###autoload
(defun gnus-agent-get-undownloaded-list ()
  "Construct list of articles that have not been downloaded."
  (let ((gnus-command-method (gnus-find-method-for-group gnus-newsgroup-name)))
    (when (set (make-local-variable 'gnus-newsgroup-agentized)
               (gnus-agent-method-p gnus-command-method))
      (let* ((alist (gnus-agent-load-alist gnus-newsgroup-name))
             (headers (sort (mapcar (lambda (h)
                                      (mail-header-number h))
                                    gnus-newsgroup-headers) '<))
             (cached (and gnus-use-cache gnus-newsgroup-cached))
             (undownloaded (list nil))
             (tail-undownloaded undownloaded)
             (unfetched (list nil))
             (tail-unfetched unfetched))
	(while (and alist headers)
	  (let ((a (caar alist))
		(h (car headers)))
	    (cond ((< a h)
		   ;; Ignore IDs in the alist that are not being
		   ;; displayed in the summary.
		   (setq alist (cdr alist)))
		  ((> a h)
                   ;; Headers that are not in the alist should be
                   ;; fictitious (see nnagent-retrieve-headers); they
                   ;; imply that this article isn't in the agent.
		   (gnus-agent-append-to-list tail-undownloaded h)
		   (gnus-agent-append-to-list tail-unfetched    h)
                   (setq headers (cdr headers)))
		  ((cdar alist)
		   (setq alist (cdr alist))
		   (setq headers (cdr headers))
		   nil                  ; ignore already downloaded
		   )
		  (t
		   (setq alist (cdr alist))
		   (setq headers (cdr headers))

                   ;; This article isn't in the agent.  Check to see
                   ;; if it is in the cache.  If it is, it's been
                   ;; downloaded.
                   (while (and cached (< (car cached) a))
                     (setq cached (cdr cached)))
                   (unless (equal a (car cached))
                     (gnus-agent-append-to-list tail-undownloaded a))))))

	(while headers
          (let ((num (pop headers)))
            (gnus-agent-append-to-list tail-undownloaded num)
            (gnus-agent-append-to-list tail-unfetched    num)))

	(setq gnus-newsgroup-undownloaded (cdr undownloaded)
              gnus-newsgroup-unfetched    (cdr unfetched))))))

(defun gnus-agent-catchup ()
  "Mark as read all unhandled articles.
An article is unhandled if it is neither cached, nor downloaded, nor
downloadable."
  (interactive)
  (save-excursion
    (let ((articles gnus-newsgroup-undownloaded))
      (when (or gnus-newsgroup-downloadable
                gnus-newsgroup-cached)
        (setq articles (gnus-sorted-ndifference
			(gnus-sorted-ndifference
			 (copy-tree articles)
			 gnus-newsgroup-downloadable)
			gnus-newsgroup-cached)))

      (while articles
        (gnus-summary-mark-article
         (pop articles) gnus-catchup-mark)))
    (gnus-summary-position-point)))

(defun gnus-agent-summary-fetch-series ()
  "Fetch the process-marked articles into the Agent."
  (interactive)
  (when gnus-newsgroup-processable
    (setq gnus-newsgroup-downloadable
          (let* ((dl gnus-newsgroup-downloadable)
		 (processable (sort (copy-tree gnus-newsgroup-processable) '<))
                 (gnus-newsgroup-downloadable processable))
	    (gnus-agent-summary-fetch-group)

            ;; For each article that I processed that is no longer
            ;; undownloaded, remove its processable mark.

	    (mapc #'gnus-summary-remove-process-mark
		  (gnus-sorted-ndifference gnus-newsgroup-processable gnus-newsgroup-undownloaded))

            ;; The preceding call to (gnus-agent-summary-fetch-group)
            ;; updated the temporary gnus-newsgroup-downloadable to
            ;; remove each article successfully fetched.  Now, I
            ;; update the real gnus-newsgroup-downloadable to only
            ;; include undownloaded articles.
	    (gnus-sorted-ndifference dl (gnus-sorted-ndifference processable gnus-newsgroup-undownloaded))))))

(defun gnus-agent-summary-fetch-group (&optional all)
  "Fetch the downloadable articles in the group.
Optional arg ALL, if non-nil, means to fetch all articles."
  (interactive "P")
  (let ((articles
	 (if all gnus-newsgroup-articles
	   gnus-newsgroup-downloadable))
	(gnus-command-method (gnus-find-method-for-group gnus-newsgroup-name))
        fetched-articles)
    (gnus-agent-while-plugged
      (unless articles
        (error "No articles to download"))
      (gnus-agent-with-fetch
        (setq gnus-newsgroup-undownloaded
              (gnus-sorted-ndifference
               gnus-newsgroup-undownloaded
               (setq fetched-articles
                     (gnus-agent-fetch-articles
                      gnus-newsgroup-name articles)))))
      (save-excursion
        (dolist (article articles)
          (let ((was-marked-downloadable
                 (memq article gnus-newsgroup-downloadable)))
            (cond (gnus-agent-mark-unread-after-downloaded
                   (setq gnus-newsgroup-downloadable
                         (delq article gnus-newsgroup-downloadable))
		   (when (and (not (member article gnus-newsgroup-dormant))
			      (not (member article gnus-newsgroup-marked)))
		     (gnus-summary-mark-article article gnus-unread-mark)))
                  (was-marked-downloadable
                   (gnus-summary-set-agent-mark article t)))
            (when (gnus-summary-goto-subject article nil t)
              (gnus-summary-update-download-mark article))))))
    fetched-articles))

(defun gnus-agent-fetch-selected-article ()
  "Fetch the current article as it is selected.
This can be added to `gnus-select-article-hook' or
`gnus-mark-article-hook'."
  (let ((gnus-command-method gnus-current-select-method))
    (when (and gnus-plugged (gnus-agent-method-p gnus-command-method))
      (when (gnus-agent-fetch-articles
             gnus-newsgroup-name
	     (list gnus-current-article))
	(setq gnus-newsgroup-undownloaded
	      (delq gnus-current-article gnus-newsgroup-undownloaded))
        (gnus-summary-update-download-mark gnus-current-article)))))

;;;
;;; Internal functions
;;;

(defun gnus-agent-synchronize-group-flags (group actions server)
  "Update a plugged group by performing the indicated actions."
  (let* ((gnus-command-method (gnus-server-to-method server))
	 (info
	  ;; This initializer is required as gnus-request-set-mark
	  ;; calls gnus-group-real-name to strip off the host name
	  ;; before calling the backend.  Now that the backend is
	  ;; trying to call gnus-request-set-mark, I have to
	  ;; reconstruct the original group name.
	  (or (gnus-get-info group)
	      (gnus-get-info
	       (setq group (gnus-group-full-name
			    group gnus-command-method))))))
    (gnus-request-set-mark group actions)

    (when info
      (dolist (action actions)
	(let ((range (nth 0 action))
	      (what  (nth 1 action))
	      (marks (nth 2 action)))
	  (dolist (mark marks)
	    (cond ((eq mark 'read)
		   (setf (gnus-info-read info)
			 (funcall (if (eq what 'add)
				      #'gnus-range-add
				    #'gnus-remove-from-range)
				  (gnus-info-read info)
				  range))
		   (gnus-get-unread-articles-in-group
		    info
		    (gnus-active (gnus-info-group info))))
		  ((memq mark '(tick))
		   (let ((info-marks (assoc mark (gnus-info-marks info))))
		     (unless info-marks
                       (push (setq info-marks (list mark))
                             (gnus-info-marks info)))
                     (setcdr info-marks
                             (funcall (if (eq what 'add)
                                          #'gnus-range-add
                                        #'gnus-remove-from-range)
                                      (cdr info-marks)
                                      range))))))))

      ;; Marks can be synchronized at any time by simply toggling from
      ;; unplugged to plugged.  If that is what is happening right now,
      ;; make sure that the group buffer is up to date.
      (when (gnus-buffer-live-p gnus-group-buffer)
        (gnus-group-update-group group t)))
    nil))

(defun gnus-agent-save-active (method &optional groups-p)
  "Sync the agent's active file with the current buffer.
Pass non-nil for GROUPS-P if the buffer starts out in groups format.
Regardless, both the file and the buffer end up in active format
if METHOD is agentized; otherwise the function is a no-op."
  (when (gnus-agent-method-p method)
    (let* ((gnus-command-method method)
	   (new (gnus-make-hashtable (count-lines (point-min) (point-max))))
	   (file (gnus-agent-lib-file "active")))
      (if groups-p
	  (gnus-groups-to-gnus-format nil new)
	(gnus-active-to-gnus-format nil new))
      (gnus-agent-write-active file new)
      (erase-buffer)
      (let ((nnheader-file-coding-system gnus-agent-file-coding-system))
	(nnheader-insert-file-contents file)))))

(defun gnus-agent-write-active (file new)
    (gnus-make-directory (file-name-directory file))
    (let ((nnmail-active-file-coding-system gnus-agent-file-coding-system))
      ;; The hashtable contains real names of groups.  However, do NOT
      ;; add the foreign server prefix as gnus-active-to-gnus-format
      ;; will add it while reading the file.
      (gnus-write-active-file file new nil)))

;;;###autoload
(defun gnus-agent-possibly-alter-active (group active &optional info)
  "Possibly expand a group's active range to include articles
downloaded into the agent."
  (let* ((gnus-command-method (or gnus-command-method
                                  (gnus-find-method-for-group group))))
    (when (gnus-agent-method-p gnus-command-method)
      (let* ((local (gnus-agent-get-local group))
             (active-min (or (car active) 0))
             (active-max (or (cdr active) 0))
             (agent-min (or (car local) active-min))
             (agent-max (or (cdr local) active-max)))

        (when (< agent-min active-min)
          (setcar active agent-min))

        (when (> agent-max active-max)
          (setcdr active agent-max))

        (when (and info (< agent-max (- active-min 100)))
          ;; I'm expanding the active range by such a large amount
          ;; that there is a gap of more than 100 articles between the
          ;; last article known to the agent and the first article
          ;; currently available on the server.  This gap contains
          ;; articles that have been lost, mark them as read so that
          ;; gnus doesn't waste resources trying to fetch them.

          ;; NOTE: I don't do this for smaller gaps (< 100) as I don't
          ;; want to modify the local file everytime someone restarts
          ;; gnus.  The small gap will cause a tiny performance hit
          ;; when gnus tries, and fails, to retrieve the articles.
          ;; Still that should be smaller than opening a buffer,
          ;; printing this list to the buffer, and then writing it to a
          ;; file.

          (let ((read (gnus-info-read info)))
            (setf (gnus-info-read info)
                  (gnus-range-add
                   read
                   (list (cons (1+ agent-max)
                               (1- active-min))))))

          ;; Lie about the agent's local range for this group to
          ;; disable the set read each time this server is opened.
          ;; NOTE: Opening this group will restore the valid local
          ;; range but it will also expand the local range to
          ;; encompass the new active range.
          (gnus-agent-set-local group agent-min (1- active-min)))))))

(defun gnus-agent-save-group-info (method group active)
  "Update a single group's active range in the agent's copy of the server's active file."
  (when (gnus-agent-method-p method)
    (let* ((gnus-command-method (or method gnus-command-method))
	   (coding-system-for-write nnheader-file-coding-system)
	   (file-name-coding-system nnmail-pathname-coding-system)
	   (file (gnus-agent-lib-file "active"))
	   oactive-min oactive-max)
      (gnus-make-directory (file-name-directory file))
      (with-temp-file file
	;; Emacs got problem to match non-ASCII group in multibyte buffer.

	;; FIXME: Is this still an issue now that group names are
	;; always strings?
	;(mm-disable-multibyte)
	(when (file-exists-p file)
	  (nnheader-insert-file-contents file)

          (goto-char (point-min))
          (when (re-search-forward
                 (concat "^" (regexp-quote group) " ") nil t)
            (save-excursion
              (setq oactive-max (read (current-buffer))	  ;; max
                    oactive-min (read (current-buffer)))) ;; min
            (gnus-delete-line)))
	(when active
	  (insert (format "%s %d %d y\n" group
			  (max (or oactive-max (cdr active)) (cdr active))
			  (min (or oactive-min (car active)) (car active))))
	  (goto-char (point-max))
	  (while (search-backward "\\." nil t)
	    (delete-char 1)))))))

(defun gnus-agent-get-group-info (method group)
  "Get a single group's active range in the agent's copy of the server's active file."
  (when (gnus-agent-method-p method)
    (let* ((gnus-command-method (or method gnus-command-method))
	   (coding-system-for-write nnheader-file-coding-system)
	   (file-name-coding-system nnmail-pathname-coding-system)
	   (file (gnus-agent-lib-file "active"))
	   oactive-min oactive-max)
      (gnus-make-directory (file-name-directory file))
      (with-temp-buffer
	;; Emacs got problem to match non-ASCII group in multibyte buffer.
	;(mm-disable-multibyte)
	(when (file-exists-p file)
	  (nnheader-insert-file-contents file)

          (goto-char (point-min))
          (when (re-search-forward
                 (concat "^" (regexp-quote group) " ") nil t)
            (save-excursion
              (setq oactive-max (read (current-buffer))	;; max
                    oactive-min (read (current-buffer))) ;; min
	      (cons oactive-min oactive-max))))))))

(defun gnus-agent-group-path (group)
  "Translate GROUP into a file name."

  ;; NOTE: This is what nnmail-group-pathname does as of Apr 2003.
  ;; The two methods must be kept synchronized, which is why
  ;; gnus-agent-group-pathname was added.

  (setq group
        (nnheader-translate-file-chars
         (nnheader-replace-duplicate-chars-in-string
          (nnheader-replace-chars-in-string
           (gnus-group-real-name group)
           ?/ ?_)
          ?. ?_)))
  (if (or nnmail-use-long-file-names
          (file-directory-p (expand-file-name group (gnus-agent-directory))))
      group
    (nnheader-replace-chars-in-string group ?. ?/)))

(defun gnus-agent-group-pathname (group)
  "Translate GROUP into a file name."
  ;; nnagent uses nnmail-group-pathname to read articles while
  ;; unplugged.  The agent must, therefore, use the same directory
  ;; while plugged.
  (nnmail-group-pathname
   (gnus-group-real-name group)
   (if gnus-command-method
       (gnus-agent-directory)
     (let ((gnus-command-method (gnus-find-method-for-group group)))
       (gnus-agent-directory)))))

(defun gnus-agent-get-function (method)
  (if (gnus-online method)
      (car method)
    (require 'nnagent)
    'nnagent))

(defun gnus-agent-covered-methods ()
  "Return the subset of methods that are covered by the agent."
  (delq nil (mapcar #'gnus-server-to-method gnus-agent-covered-methods)))

;;; History functions

(defun gnus-agent-history-buffer ()
  (cdr (assoc (gnus-agent-method) gnus-agent-history-buffers)))

(defun gnus-agent-open-history ()
  (save-excursion
    (push (cons (gnus-agent-method)
		(set-buffer (gnus-get-buffer-create
			     (format " *Gnus agent %s history*"
				     (gnus-agent-method)))))
	  gnus-agent-history-buffers)
    ;(mm-disable-multibyte) ;; everything is binary
    (erase-buffer)
    (insert "\n")
    (let ((file (gnus-agent-lib-file "history")))
      (when (file-exists-p file)
	(nnheader-insert-file-contents file))
      (set (make-local-variable 'gnus-agent-file-name) file))))

(defun gnus-agent-close-history ()
  (when (gnus-buffer-live-p gnus-agent-current-history)
    (kill-buffer gnus-agent-current-history)
    (setq gnus-agent-history-buffers
	  (delq (assoc (gnus-agent-method) gnus-agent-history-buffers)
		gnus-agent-history-buffers))))

;;;
;;; Fetching
;;;

(defun gnus-agent-fetch-articles (group articles)
  "Fetch ARTICLES from GROUP and put them into the Agent."
  (when (and articles
	     (gnus-online (gnus-group-method group)))
    (gnus-agent-load-alist group)
    (let* ((alist gnus-agent-article-alist)
           (headers (if (< (length articles) 2) nil gnus-newsgroup-headers))
           (selected-sets (list nil))
           (current-set-size 0)
           article
           header-number)
      ;; Check each article
      (while (setq article (pop articles))
        ;; Skip alist entries preceding this article
        (while (> article (or (caar alist) (1+ article)))
          (setq alist (cdr alist)))

        ;; Prune off articles that we have already fetched.
        (unless (and (eq article (caar alist))
                     (cdar alist))
          ;; Skip headers preceding this article
          (while (> article
                    (setq header-number
                          (let* ((header (car headers)))
                            (if header
                                (mail-header-number header)
                              (1+ article)))))
            (setq headers (cdr headers)))

          ;; Add this article to the current set
          (setcar selected-sets (cons article (car selected-sets)))

          ;; Update the set size, when the set is too large start a
          ;; new one.  I do this after adding the article as I want at
          ;; least one article in each set.
          (when (< gnus-agent-max-fetch-size
                   (setq current-set-size
			 (+ current-set-size
			    (if (= header-number article)
                                (let ((char-size (mail-header-chars
                                                  (car headers))))
                                  (if (<= char-size 0)
                                      ;; The char size was missing/invalid,
                                      ;; assume a worst-case situation of
                                      ;; 65 char/line.  If the line count
                                      ;; is missing, arbitrarily assume a
                                      ;; size of 1000 characters.
				      (max (* 65 (mail-header-lines
						  (car headers)))
					   1000)
                                    char-size))
			      0))))
            (setcar selected-sets (nreverse (car selected-sets)))
            (setq selected-sets (cons nil selected-sets)
                  current-set-size 0))))

      (when (or (cdr selected-sets) (car selected-sets))
        (let* ((fetched-articles (list nil))
               (tail-fetched-articles fetched-articles)
               (dir (gnus-agent-group-pathname group))
               (date (time-to-days nil))
               (case-fold-search t)
               pos crosses
	       (file-name-coding-system nnmail-pathname-coding-system))

          (setcar selected-sets (nreverse (car selected-sets)))
          (setq selected-sets (nreverse selected-sets))

          (gnus-make-directory dir)
	  (gnus-message 7 "Fetching articles for %s..." group)

          (unwind-protect
              (while (setq articles (pop selected-sets))
                ;; Fetch the articles from the backend.
                (if (gnus-check-backend-function 'retrieve-articles group)
                    (setq pos (gnus-retrieve-articles articles group))
                  (with-temp-buffer
                    (let (article)
                      (while (setq article (pop articles))
                        (gnus-message 10 "Fetching article %s for %s..."
				      article group)
                        (when (or
                               (gnus-backlog-request-article group article
                                                             nntp-server-buffer)
                               (gnus-request-article article group))
                          (goto-char (point-max))
                          (push (cons article (point)) pos)
                          (insert-buffer-substring nntp-server-buffer)))
                      (copy-to-buffer
		       nntp-server-buffer (point-min) (point-max))
                      (setq pos (nreverse pos)))))
                ;; Then save these articles into the Agent.
                (with-current-buffer nntp-server-buffer
                  (while pos
                    (narrow-to-region (cdar pos) (or (cdadr pos) (point-max)))
                    (goto-char (point-min))
                    (unless (eobp) ;; Don't save empty articles.
                      (when (search-forward "\n\n" nil t)
                        (when (search-backward "\nXrefs: " nil t)
                          ;; Handle cross posting.
                          (goto-char (match-end 0)) ; move to end of header name
                          (skip-chars-forward "^ ") ; skip server name
                          (skip-chars-forward " ")
                          (setq crosses nil)
                          (while (looking-at "\\([^: \n]+\\):\\([0-9]+\\) *")
                            (push (cons (match-string 1)
                                        (string-to-number (match-string 2)))
                                  crosses)
                            (goto-char (match-end 0)))
                          (gnus-agent-crosspost crosses (caar pos) date)))
                      (goto-char (point-min))
                      (let ((coding-system-for-write
                             gnus-agent-file-coding-system))
                        (write-region (point-min) (point-max)
                                      (concat dir (number-to-string (caar pos)))
                                      nil 'silent))

                      (gnus-agent-append-to-list
		       tail-fetched-articles (caar pos)))
                    (widen)
                    (setq pos (cdr pos)))))

            (gnus-agent-save-alist group (cdr fetched-articles) date)
	    (gnus-agent-update-files-total-fetched-for group (cdr fetched-articles))

            (gnus-message 7 ""))
          (cdr fetched-articles))))))

(defun gnus-agent-unfetch-articles (group articles)
  "Delete ARTICLES that were fetched from GROUP into the agent."
  (when articles
    (gnus-agent-with-refreshed-group
     group
     (gnus-agent-load-alist group)
     (let* ((alist (cons nil gnus-agent-article-alist))
	    (articles (sort articles #'<))
	    (next-possibility alist)
	    (delete-this (pop articles)))
       (while (and (cdr next-possibility) delete-this)
	 (let ((have-this (caar (cdr next-possibility))))
	   (cond
	    ((< delete-this have-this)
	     (setq delete-this (pop articles)))
	    ((= delete-this have-this)
	     (let ((timestamp (cdar (cdr next-possibility))))
	       (when timestamp
		 (let* ((file-name (concat (gnus-agent-group-pathname group)
					   (number-to-string have-this)))
			(size-file
			 (float (or (and gnus-agent-total-fetched-hashtb
					 (file-attribute-size
					  (file-attributes file-name)))
				    0)))
			(file-name-coding-system
			 nnmail-pathname-coding-system))
		   (delete-file file-name)
		   (gnus-agent-update-files-total-fetched-for
		    group (- size-file)))))

	     (setcdr next-possibility (cddr next-possibility)))
	    (t
	     (setq next-possibility (cdr next-possibility))))))
       (setq gnus-agent-article-alist (cdr alist))
       (gnus-agent-save-alist group)))))

(defun gnus-agent-crosspost (crosses article &optional date)
  (setq date (or date t))

  (let (gnus-agent-article-alist group alist beg end)
    (with-current-buffer gnus-agent-overview-buffer
      (when (nnheader-find-nov-line article)
	(forward-word 1)
	(setq beg (point))
	(setq end (progn (forward-line 1) (point)))))
    (while crosses
      (setq group (caar crosses))
      (unless (setq alist (assoc group gnus-agent-group-alist))
	(push (setq alist (list group (gnus-agent-load-alist (caar crosses))))
	      gnus-agent-group-alist))
      (setcdr alist (cons (cons (cdar crosses) date) (cdr alist)))
      (with-current-buffer (gnus-get-buffer-create
			    (format " *Gnus agent overview %s*"group))
	(when (= (point-max) (point-min))
	  (push (cons group (current-buffer)) gnus-agent-buffer-alist)
	  (ignore-errors
	   (let ((file-name-coding-system nnmail-pathname-coding-system))
	     (nnheader-insert-file-contents
	      (gnus-agent-article-name ".overview" group)))))
	(nnheader-find-nov-line (string-to-number (cdar crosses)))
	(insert (string-to-number (cdar crosses)))
	(insert-buffer-substring gnus-agent-overview-buffer beg end)
        (gnus-agent-check-overview-buffer))
      (setq crosses (cdr crosses)))))

(defun gnus-agent-backup-overview-buffer ()
  (when gnus-newsgroup-name
    (let ((root (gnus-agent-article-name ".overview" gnus-newsgroup-name))
          (cnt 0)
          name
	  (file-name-coding-system nnmail-pathname-coding-system))
      (while (file-exists-p
	      (setq name (concat root "~"
				 (int-to-string (setq cnt (1+ cnt))) "~"))))
      (write-region (point-min) (point-max) name nil 'no-msg)
      (gnus-message 1 "Created backup copy of overview in %s." name)))
  t)

(defun gnus-agent-check-overview-buffer (&optional buffer)
  "Check the overview file given for sanity.
In particular, checks that the file is sorted by article number
and that there are no duplicates."
  (let ((prev-num -1)
        (backed-up nil))
    (save-excursion
      (when buffer
	(set-buffer buffer))
      (save-restriction
	(widen)
	(goto-char (point-min))

	(while (< (point) (point-max))
	  (let ((p (point))
		(cur (condition-case nil
			 (read (current-buffer))
		       (error nil))))
	    (cond
	     ((or (not (integerp cur))
		  (not (eq (char-after) ?\t)))
              (or backed-up
                  (setq backed-up (gnus-agent-backup-overview-buffer)))
	      (gnus-message 1
			    "Overview buffer contains garbage `%s'."
			    (buffer-substring
			     p (point-at-eol))))
	     ((= cur prev-num)
	      (or backed-up
                  (setq backed-up (gnus-agent-backup-overview-buffer)))
              (gnus-message 1
			    "Duplicate overview line for %d" cur)
	      (delete-region p (progn (forward-line 1) (point))))
	     ((< cur prev-num)
	      (or backed-up
                  (setq backed-up (gnus-agent-backup-overview-buffer)))
              (gnus-message 1 "Overview buffer not sorted!")
	      (sort-numeric-fields 1 (point-min) (point-max))
	      (goto-char (point-min))
	      (setq prev-num -1))
	     (t
	      (setq prev-num cur)))
	    (forward-line 1)))))))

(defun gnus-agent-flush-server (&optional server-or-method)
  "Flush all agent index files for every subscribed group within
  the given SERVER-OR-METHOD.  When called with nil, the current
  value of gnus-command-method identifies the server."
  (let* ((gnus-command-method (if server-or-method
				  (gnus-server-to-method server-or-method)
				gnus-command-method))
	 (alist gnus-newsrc-alist))
    (while alist
      (let ((entry (pop alist)))
	(when (gnus-methods-equal-p gnus-command-method (gnus-info-method entry))
	  (gnus-agent-flush-group (gnus-info-group entry)))))))

(defun gnus-agent-flush-group (group)
  "Flush the agent's index files such that the GROUP no longer
appears to have any local content.  The actual content, the
article files, may then be deleted using gnus-agent-expire-group.
If flushing was a mistake, the gnus-agent-regenerate-group method
provides an undo mechanism by reconstructing the index files from
the article files."
  (interactive (list (gnus-agent-read-group)))

  (let* ((gnus-command-method (or gnus-command-method
				  (gnus-find-method-for-group group)))
	 (overview (gnus-agent-article-name ".overview" group))
	 (agentview (gnus-agent-article-name ".agentview" group))
	 (file-name-coding-system nnmail-pathname-coding-system))

    (if (file-exists-p overview)
	(delete-file overview))
    (if (file-exists-p agentview)
	(delete-file agentview))

    (gnus-agent-update-view-total-fetched-for group nil gnus-command-method)
    (gnus-agent-update-view-total-fetched-for group t   gnus-command-method)

    ;(gnus-agent-set-local group nil nil)
    ;(gnus-agent-save-local t)
    (gnus-agent-save-group-info nil group nil)))

(defun gnus-agent-flush-cache ()
  "Flush the agent's index files such that the group no longer
appears to have any local content.  The actual content, the
article files, is then deleted using gnus-agent-expire-group.
The gnus-agent-regenerate-group method provides an undo mechanism
by reconstructing the index files from the article files."
  (interactive)
  (save-excursion
    (let ((file-name-coding-system nnmail-pathname-coding-system))
      (while gnus-agent-buffer-alist
	(set-buffer (cdar gnus-agent-buffer-alist))
	(let ((coding-system-for-write gnus-agent-file-coding-system))
	  (write-region (point-min) (point-max)
			(gnus-agent-article-name ".overview"
						 (caar gnus-agent-buffer-alist))
			nil 'silent))
	(setq gnus-agent-buffer-alist (cdr gnus-agent-buffer-alist)))
      (while gnus-agent-group-alist
	(with-temp-file (gnus-agent-article-name
			 ".agentview" (caar gnus-agent-group-alist))
	  (princ (cdar gnus-agent-group-alist))
	  (insert "\n")
	  (princ 1 (current-buffer))
	  (insert "\n"))
	(setq gnus-agent-group-alist (cdr gnus-agent-group-alist))))))

;;;###autoload
(defun gnus-agent-find-parameter (group symbol)
  "Search for GROUPs SYMBOL in the group's parameters, the group's
topic parameters, the group's category, or the customizable
variables.  Returns the first non-nil value found."
  (or (gnus-group-find-parameter group symbol t)
      (gnus-group-parameter-value (cdr (gnus-group-category group)) symbol t)
      (symbol-value
       (cdr
        (assq symbol
              '((agent-short-article . gnus-agent-short-article)
                (agent-long-article . gnus-agent-long-article)
                (agent-low-score . gnus-agent-low-score)
                (agent-high-score . gnus-agent-high-score)
                (agent-days-until-old . gnus-agent-expire-days)
                (agent-enable-expiration
                 . gnus-agent-enable-expiration)
                (agent-predicate . gnus-agent-predicate)))))))

(defun gnus-agent-fetch-headers (group)
  "Fetch interesting headers into the agent.  The group's overview
file will be updated to include the headers while a list of available
article numbers will be returned."
  (let* ((fetch-all (and gnus-agent-consider-all-articles
                         ;; Do not fetch all headers if the predicate
                         ;; implies that we only consider unread articles.
                         (not (gnus-predicate-implies-unread
                               (gnus-agent-find-parameter group
                                                          'agent-predicate)))))
         (articles (if fetch-all
		       (if gnus-newsgroup-maximum-articles
			   (let ((active (gnus-active group)))
			     (gnus-uncompress-range
			      (cons (max (car active)
					 (- (cdr active)
					    gnus-newsgroup-maximum-articles
					    -1))
				    (cdr active))))
			 (gnus-uncompress-range (gnus-active group)))
                     (gnus-list-of-unread-articles group)))
         (gnus-decode-encoded-word-function 'identity)
	 (gnus-decode-encoded-address-function 'identity)
         (file (gnus-agent-article-name ".overview" group))
	 (file-name-coding-system nnmail-pathname-coding-system))

    (unless fetch-all
      ;; Add articles with marks to the list of article headers we want to
      ;; fetch.  Don't fetch articles solely on the basis of a recent or seen
      ;; mark, but do fetch recent or seen articles if they have other, more
      ;; interesting marks.  (We have to fetch articles with boring marks
      ;; because otherwise the agent will remove their marks.)
      (dolist (arts (gnus-info-marks (gnus-get-info group)))
        (unless (memq (car arts) '(seen recent killed cache))
          (setq articles (gnus-range-add articles (cdr arts)))))
      (setq articles (sort (gnus-uncompress-sequence articles) '<)))

    ;; At this point, I have the list of articles to consider for
    ;; fetching.  This is the list that I'll return to my caller. Some
    ;; of these articles may have already been fetched.  That's OK as
    ;; the fetch article code will filter those out.  Internally, I'll
    ;; filter this list to just those articles whose headers need to
    ;; be fetched.
    (let ((articles articles))
      ;; Remove known articles.
      (when (and (or gnus-agent-cache
                     (not gnus-plugged))
                 (gnus-agent-load-alist group))
        ;; Remove articles marked as downloaded.
        (if fetch-all
            ;; I want to fetch all headers in the active range.
            ;; Therefore, exclude only those headers that are in the
            ;; article alist.
            ;; NOTE: This is probably NOT what I want to do after
            ;; agent expiration in this group.
            (setq articles (gnus-agent-uncached-articles articles group))

          ;; I want to only fetch those headers that have never been
          ;; fetched.  Therefore, exclude all headers that are, or
          ;; WERE, in the article alist.
          (let ((low (1+ (caar (last gnus-agent-article-alist))))
                (high (cdr (gnus-active group))))
            ;; Low can be greater than High when the same group is
            ;; fetched twice in the same session {The first fetch will
            ;; fill the article alist such that (last
            ;; gnus-agent-article-alist) equals (cdr (gnus-active
            ;; group))}.  The addition of one(the 1+ above) then
            ;; forces Low to be greater than High.  When this happens,
            ;; gnus-list-range-intersection returns nil which
            ;; indicates that no headers need to be fetched. -- Kevin
            (setq articles (gnus-list-range-intersection
                            articles (list (cons low high)))))))

      (when articles
	(gnus-message
	 10 "gnus-agent-fetch-headers: undownloaded articles are `%s'"
	 (gnus-compress-sequence articles t)))

      (with-current-buffer nntp-server-buffer
        (if articles
            (progn
	      (gnus-message 8 "Fetching headers for %s..." group)

              ;; Fetch them.
              (gnus-make-directory (nnheader-translate-file-chars
                                    (file-name-directory file) t))

              (unless (eq 'nov (gnus-retrieve-headers articles group))
                (nnvirtual-convert-headers))
              (gnus-agent-check-overview-buffer)
              ;; Move these headers to the overview buffer so that
              ;; gnus-agent-braid-nov can merge them with the contents
              ;; of FILE.
              (copy-to-buffer
	       gnus-agent-overview-buffer (point-min) (point-max))
	      ;; NOTE: Call g-a-brand-nov even when the file does not
	      ;; exist.  As a minimum, it will validate the article
	      ;; numbers already in the buffer.
	      (gnus-agent-braid-nov articles file)
              (let ((coding-system-for-write
                     gnus-agent-file-coding-system))
                (gnus-agent-check-overview-buffer)
                (write-region (point-min) (point-max) file nil 'silent))
	      (gnus-agent-update-view-total-fetched-for group t)
              (gnus-agent-save-alist group articles nil)
              articles)
          (ignore-errors
            (erase-buffer)
            (nnheader-insert-file-contents file)))))
    articles))

(defsubst gnus-agent-read-article-number ()
  "Reads the article number at point.  Returns nil when a valid article number can not be read."

  (when (looking-at "[0-9]+\t")
    (read (current-buffer))))

(defsubst gnus-agent-copy-nov-line (article)
  "Copy the indicated ARTICLE from the overview buffer to the nntp server buffer."
  (let (art b e)
    (set-buffer gnus-agent-overview-buffer)
    (while (and (not (eobp))
		(or (not (setq art (gnus-agent-read-article-number)))
		    (< art article)))
      (forward-line 1))
    (beginning-of-line)
    (if (or (eobp)
	    (not (eq article art)))
	(set-buffer nntp-server-buffer)
      (setq b (point))
      (setq e (progn (forward-line 1) (point)))
      (set-buffer nntp-server-buffer)
      (insert-buffer-substring gnus-agent-overview-buffer b e))))

(defun gnus-agent-braid-nov (articles file)
  "Merge agent overview data with given file.
Takes unvalidated headers for ARTICLES from
`gnus-agent-overview-buffer' and validated headers from the given
FILE and places the combined valid headers into
`nntp-server-buffer'.  This function can be used, when file
doesn't exist, to valid the overview buffer."
  (let (start last)
    (set-buffer gnus-agent-overview-buffer)
    (goto-char (point-min))
    (set-buffer nntp-server-buffer)
    (erase-buffer)
    (when (file-exists-p file)
      (nnheader-insert-file-contents file))
    (goto-char (point-max))
    (forward-line -1)

    (unless (or (= (point-min) (point-max))
		(< (setq last (read (current-buffer))) (car articles)))
      ;; Old and new overlap -- We do it the hard way.
      (when (nnheader-find-nov-line (car articles))
        ;; Replacing existing NOV entry
        (delete-region (point) (progn (forward-line 1) (point))))
      (gnus-agent-copy-nov-line (pop articles))

      (ignore-errors
	(while articles
	  (while (let ((art (read (current-buffer))))
		   (cond ((< art (car articles))
			  (forward-line 1)
			  t)
			 ((= art (car articles))
			  (beginning-of-line)
			  (delete-region
			   (point) (progn (forward-line 1) (point)))
			  nil)
			 (t
			  (beginning-of-line)
			  nil))))

	  (gnus-agent-copy-nov-line (pop articles)))))

    (goto-char (point-max))

    ;; Append the remaining lines
    (when articles
      (when last
	(set-buffer gnus-agent-overview-buffer)
	(setq start (point))
	(set-buffer nntp-server-buffer))

      (let ((p (point)))
	(insert-buffer-substring gnus-agent-overview-buffer start)
	(goto-char p))

      (setq last (or last -134217728))
      (while (catch 'problems
	       (let (sort art)
		 (while (not (eobp))
		   (setq art (gnus-agent-read-article-number))
		   (cond ((not art)
			  ;; Bad art num - delete this line
			  (beginning-of-line)
			  (delete-region (point) (progn (forward-line 1) (point))))
			 ((< art last)
			  ;; Art num out of order - enable sort
			  (setq sort t)
			  (forward-line 1))
			 ((= art last)
			  ;; Bad repeat of art number - delete this line
			  (beginning-of-line)
			  (delete-region (point) (progn (forward-line 1) (point))))
			 (t
			  ;; Good art num
			  (setq last art)
			  (forward-line 1))))
		 (when sort
		   ;; something is seriously wrong as we simply shouldn't see out-of-order data.
		   ;; First, we'll fix the sort.
		   (sort-numeric-fields 1 (point-min) (point-max))

		   ;; but now we have to consider that we may have duplicate rows...
		   ;; so reset to beginning of file
		   (goto-char (point-min))
		   (setq last -134217728)

		   ;; and throw a code that restarts this scan
		   (throw 'problems t))
		 nil))))))

;; Keeps the compiler from warning about the free variable in
;; gnus-agent-read-agentview.
(defvar gnus-agent-read-agentview)

(defun gnus-agent-load-alist (group)
  "Load the article-state alist for GROUP."
  ;; Bind free variable that's used in `gnus-agent-read-agentview'.
  (let* ((gnus-agent-read-agentview group)
	 (file-name-coding-system nnmail-pathname-coding-system)
	 (agentview (gnus-agent-article-name ".agentview" group)))
    (setq gnus-agent-article-alist
	  (and (file-exists-p agentview)
	       (gnus-cache-file-contents
		agentview
		'gnus-agent-file-loading-cache
		'gnus-agent-read-agentview)))))

(defun gnus-agent-read-agentview (file)
  "Load FILE and do a `read' there."
  (with-temp-buffer
    (condition-case nil
	(progn
	  (nnheader-insert-file-contents file)
	  (goto-char (point-min))
	  (let ((alist (read (current-buffer)))
		(version (condition-case nil (read (current-buffer))
			   (end-of-file 0)))
		changed-version)

	    (cond
	     ((= version 0)
	      (let ((inhibit-quit t)
		    entry)
		(gnus-agent-open-history)
		(set-buffer (gnus-agent-history-buffer))
		(goto-char (point-min))
		(while (not (eobp))
		  (if (and (looking-at
			    "[^\t\n]+\t\\([0-9]+\\)\t\\([^ \n]+\\) \\([0-9]+\\)")
			   (string= (match-string 2)
				    gnus-agent-read-agentview)
			   (setq entry (assoc (string-to-number (match-string 3)) alist)))
		      (setcdr entry (string-to-number (match-string 1))))
		  (forward-line 1))
		(gnus-agent-close-history)
		(setq changed-version t)))
	     ((= version 1)
	      (setq changed-version (not (= 1 gnus-agent-article-alist-save-format))))
	     ((= version 2)
	      (let (state sequence uncomp)
		(while alist
		  (setq state (caar alist)
			sequence (inline (gnus-uncompress-range (cdar alist)))
			alist (cdr alist))
		  (while sequence
		    (push (cons (pop sequence) state) uncomp)))
		(setq alist (sort uncomp 'car-less-than-car)))
	      (setq changed-version (not (= 2 gnus-agent-article-alist-save-format)))))
	    (when changed-version
	      (let ((gnus-agent-article-alist alist))
		(gnus-agent-save-alist gnus-agent-read-agentview)))
	    alist))
      ((end-of-file file-error)
       ;; The agentview file is missing.
       (condition-case nil
	   ;; If the agent directory exists, attempt to perform a brute-force
	   ;; reconstruction of its contents.
	   (let* (alist
		  (file-name-coding-system nnmail-pathname-coding-system)
		  (file-attributes (directory-files-and-attributes
				    (gnus-agent-article-name
				     "" gnus-agent-read-agentview)
				    nil "\\`[0-9]+\\'" t)))
	     (while file-attributes
	       (let ((fa (pop file-attributes)))
		 (unless (file-attribute-type (cdr fa))
		   (push (cons (string-to-number (car fa))
			       (time-to-days
				(file-attribute-access-time (cdr fa))))
			 alist))))
	     alist)
	 (file-error nil))))))

(defun gnus-agent-save-alist (group &optional articles state)
  "Save the article-state alist for GROUP."
  (let* ((file-name-coding-system nnmail-pathname-coding-system)
	 (prev (cons nil gnus-agent-article-alist))
	 (all prev)
	 print-level print-length article)
    (while (setq article (pop articles))
      (while (and (cdr prev)
                  (< (caadr prev) article))
	(setq prev (cdr prev)))
      (cond
       ((not (cdr prev))
	(setcdr prev (list (cons article state))))
       ((> (caadr prev) article)
	(setcdr prev (cons (cons article state) (cdr prev))))
       ((= (caadr prev) article)
	(setcdr (cadr prev) state)))
      (setq prev (cdr prev)))
    (setq gnus-agent-article-alist (cdr all))

    (gnus-agent-set-local group
                          (caar gnus-agent-article-alist)
                          (caar (last gnus-agent-article-alist)))

    (gnus-make-directory (gnus-agent-article-name "" group))
    (with-temp-file (gnus-agent-article-name ".agentview" group)
      (cond ((eq gnus-agent-article-alist-save-format 1)
             (princ gnus-agent-article-alist (current-buffer)))
            ((eq gnus-agent-article-alist-save-format 2)
             (let ((alist gnus-agent-article-alist)
		   article-id day-of-download comp-list compressed)
	       (while alist
		 (setq article-id (caar alist)
		       day-of-download (cdar alist)
		       comp-list (assq day-of-download compressed)
		       alist (cdr alist))
		 (if comp-list
		     (setcdr comp-list (cons article-id (cdr comp-list)))
		   (push (list day-of-download article-id) compressed)))
	       (setq alist compressed)
	       (while alist
		 (setq comp-list (pop alist))
		 (setcdr comp-list
			 (gnus-compress-sequence (nreverse (cdr comp-list)))))
               (princ compressed (current-buffer)))))
      (insert "\n")
      (princ gnus-agent-article-alist-save-format (current-buffer))
      (insert "\n"))

    (gnus-agent-update-view-total-fetched-for group nil)))

;; FIXME: Why would this be a hash table?  Wouldn't a simple alist or
;; something suffice?
(defvar gnus-agent-article-local nil
  "Hashtable holding information about a group.")
(defvar gnus-agent-article-local-times nil)
(defvar gnus-agent-file-loading-local nil)

(defun gnus-agent-load-local (&optional method)
  "Load the METHOD'S local file.  The local file contains min/max
article counts for each of the method's subscribed groups."
  (let ((gnus-command-method (or method gnus-command-method)))
    (when (or (null gnus-agent-article-local-times)
	      (zerop gnus-agent-article-local-times)
	      (not (gnus-methods-equal-p
		    gnus-command-method
		    (gethash "+method" gnus-agent-article-local))))
      (setq gnus-agent-article-local
	    (gnus-cache-file-contents
	     (gnus-agent-lib-file "local")
	     'gnus-agent-file-loading-local
	     #'gnus-agent-read-and-cache-local))
      (when gnus-agent-article-local-times
	(cl-incf gnus-agent-article-local-times)))
    gnus-agent-article-local))

(defun gnus-agent-read-and-cache-local (file)
  "Load and read FILE then bind its contents to
gnus-agent-article-local.  If that variable had `dirty' (also known as
modified) original contents, they are first saved to their own file."
  (if (and gnus-agent-article-local
           (gethash "+dirty" gnus-agent-article-local))
      (gnus-agent-save-local))
  (gnus-agent-read-local file))

(defun gnus-agent-read-local (file)
  "Load FILE and do a `read' there."
  (let ((hashtb (gnus-make-hashtable
		 (count-lines (point-min)
			      (point-max))))
        (line 1))
    (with-temp-buffer
      (condition-case nil
	  (let ((nnheader-file-coding-system gnus-agent-file-coding-system))
	    (nnheader-insert-file-contents file))
        (file-error))

      (goto-char (point-min))
      ;; Skip any comments at the beginning of the file (the only
      ;; place where they may appear)
      (while (= (following-char) ?\;)
        (forward-line 1)
        (setq line (1+ line)))

      (while (not (eobp))
        (condition-case err
            (let (group
                  min
                  max
                  (cur (current-buffer)))
              (setq group (read cur)
                    min (read cur)
                    max (read cur))

              (unless (stringp group)
                (setq group (symbol-name group)))

              ;; NOTE: The '+ 0' ensure that min and max are both numerics.
              (puthash group (cons (+ 0 min) (+ 0 max)) hashtb))
          (error
           (gnus-message 3 "Warning - invalid agent local: %s on line %d: %s"
                         file line (error-message-string err))))
        (forward-line 1)
        (setq line (1+ line))))

    (puthash "+dirty" nil hashtb)
    (puthash "+method" gnus-command-method hashtb)
    hashtb))

(defun gnus-agent-save-local (&optional force)
  "Save gnus-agent-article-local under it method's agent.lib directory."
  (let ((hashtb gnus-agent-article-local))
    (when (and hashtb
               (or force (gethash "+dirty" hashtb)))
      (let* ((gnus-command-method (gethash "+method" hashtb))
             ;; NOTE: gnus-command-method is used within gnus-agent-lib-file.
             (dest (gnus-agent-lib-file "local")))
        (gnus-make-directory (gnus-agent-lib-file ""))

	(let ((coding-system-for-write gnus-agent-file-coding-system)
	      (file-name-coding-system nnmail-pathname-coding-system))
	  (with-temp-file dest
	    ;; FIXME: Why are we letting this again?
	    (let ((gnus-command-method (gethash "+method" hashtb))
		  print-level print-length
		  (standard-output (current-buffer)))
	      (maphash (lambda (group active)
			 (cond ((null active)
				nil)
			       ((member group '("+dirty" "+method"))
				nil)
			       (t
				(when active
				  (prin1 group)
				  (princ " ")
				  (princ (car active))
				  (princ " ")
				  (princ (cdr active))
				  (princ "\n")))))
		       hashtb))))))))

(defun gnus-agent-get-local (group &optional gmane method)
  (let* ((gmane (or gmane (gnus-group-real-name group)))
         (gnus-command-method (or method (gnus-find-method-for-group group)))
         (local (gnus-agent-load-local))
         (minmax (gethash gmane local)))
    (unless minmax
      ;; Bind these so that gnus-agent-load-alist doesn't change the
      ;; current alist (i.e. gnus-agent-article-alist)
      (let* ((gnus-agent-article-alist gnus-agent-article-alist)
             (gnus-agent-file-loading-cache gnus-agent-file-loading-cache)
             (alist (gnus-agent-load-alist group)))
        (when alist
          (setq minmax
                (cons (caar alist)
                      (caar (last alist))))
          (gnus-agent-set-local group (car minmax) (cdr minmax)
                                gmane gnus-command-method local))))
    minmax))

(defun gnus-agent-set-local (group min max &optional gmane method local)
  (let* ((gmane (or gmane (gnus-group-real-name group)))
         (gnus-command-method (or method (gnus-find-method-for-group group)))
         (local (or local (gnus-agent-load-local)))
         (minmax (gethash gmane local)))
    (if (cond ((and minmax
                    (or (not (eq min (car minmax)))
                        (not (eq max (cdr minmax))))
		    min
		    max)
               (setcar (gethash gmane local) min)
               (setcdr (gethash gmane local) max)
               t)
              (minmax
               nil)
              ((and min max)
               (puthash gmane (cons min max) local)
               t)
	      (t
	       (remhash gmane local)))
        (puthash "+dirty" t local))))

(defun gnus-agent-article-name (article group)
  (expand-file-name article
		    (file-name-as-directory
                     (gnus-agent-group-pathname group))))

(defun gnus-agent-batch-confirmation (msg)
  "Show error message and return t."
  (gnus-message 1 "%s" msg)
  t)

;;;###autoload
(defun gnus-agent-batch-fetch ()
  "Start Gnus and fetch session."
  (interactive)
  (gnus)
  (let ((gnus-agent-confirmation-function 'gnus-agent-batch-confirmation))
    (gnus-agent-fetch-session))
  (gnus-group-exit))

(defun gnus-agent-fetch-session ()
  "Fetch all articles and headers that are eligible for fetching."
  (interactive)
  (unless gnus-agent-covered-methods
    (error "No servers are covered by the Gnus agent"))
  (unless gnus-plugged
    (error "Can't fetch articles while Gnus is unplugged"))
  (let ((methods (gnus-agent-covered-methods))
	groups group gnus-command-method)
    (save-excursion
      (while methods
	(setq gnus-command-method (car methods))
	(when (and (or (gnus-server-opened gnus-command-method)
		       (gnus-open-server gnus-command-method))
		   (gnus-online gnus-command-method))
	  (setq groups (gnus-groups-from-server (car methods)))
	  (gnus-agent-with-fetch
	    (while (setq group (pop groups))
	      (when (<= (gnus-group-level group)
			gnus-agent-handle-level)
		(if (or debug-on-error debug-on-quit)
		    (gnus-agent-fetch-group-1
		     group gnus-command-method)
		  (condition-case err
		      (gnus-agent-fetch-group-1
		       group gnus-command-method)
		    (error
		     (unless (funcall gnus-agent-confirmation-function
				      (format "Error %s while fetching session.  Should gnus continue? "
					      (error-message-string err)))
		       (error "Cannot fetch articles into the Gnus agent")))
		    (quit
		     (gnus-agent-regenerate-group group)
		     (unless (funcall gnus-agent-confirmation-function
				      (format
				       "%s while fetching session.  Should gnus continue? "
				       (error-message-string err)))
		       (signal 'quit
			       "Cannot fetch articles into the Gnus agent")))))))))
	(setq methods (cdr methods)))
      (gnus-run-hooks 'gnus-agent-fetched-hook)
      (gnus-message 6 "Finished fetching articles into the Gnus agent"))))

(defvar gnus-agent-short-article 500
  "Articles that have fewer lines than this are short.")

(defvar gnus-agent-long-article 1000
  "Articles that have more lines than this are long.")

(defvar gnus-agent-low-score 0
  "Articles that have a score lower than this have a low score.")

(defvar gnus-agent-high-score 0
  "Articles that have a score higher than this have a high score.")

(defun gnus-agent-fetch-group-1 (group method)
  "Fetch GROUP."
  (let ((gnus-command-method method)
	(gnus-newsgroup-name group)
	(gnus-newsgroup-dependencies gnus-newsgroup-dependencies)
        (gnus-newsgroup-headers gnus-newsgroup-headers)
	(gnus-newsgroup-scored gnus-newsgroup-scored)
	(gnus-use-cache gnus-use-cache)
	(gnus-summary-expunge-below gnus-summary-expunge-below)
	(gnus-summary-mark-below gnus-summary-mark-below)
	(gnus-orphan-score gnus-orphan-score)
	;; Maybe some other gnus-summary local variables should also
	;; be put here.

        gnus-headers
        gnus-score
        articles
        predicate info marks
	)
    (unless (gnus-check-group group)
      (error "Can't open server for %s" group))

    ;; Fetch headers.
    (when (or gnus-newsgroup-active
              (gnus-active group)
              (gnus-activate-group group))
      (let ((marked-articles gnus-newsgroup-downloadable))
        ;; Identify the articles marked for download
        (unless gnus-newsgroup-active
	  ;; The variable gnus-newsgroup-active was selected as I need
	  ;; a gnus-summary local variable that is NOT bound to any
	  ;; value (its global value should default to nil).
          (dolist (mark gnus-agent-download-marks)
            (let ((arts (cdr (assq mark (gnus-info-marks
                                         (setq info (gnus-get-info group)))))))
              (when arts
                (setq marked-articles (nconc (gnus-uncompress-range arts)
                                             marked-articles))
                ))))
        (setq marked-articles (sort marked-articles '<))

        ;; Fetch any new articles from the server
        (setq articles (gnus-agent-fetch-headers group))

        ;; Merge new articles with marked
        (setq articles (sort (append marked-articles articles) '<))

        (when articles
          ;; Parse them and see which articles we want to fetch.
          (setq gnus-newsgroup-dependencies
                (or gnus-newsgroup-dependencies
                    (gnus-make-hashtable (length articles))))
          (setq gnus-newsgroup-headers
                (or gnus-newsgroup-headers
                    (gnus-get-newsgroup-headers-xover articles nil nil
                                                      group)))
          ;; `gnus-agent-overview-buffer' may be killed for
          ;; timeout reason.  If so, recreate it.
          (gnus-agent-create-buffer)

          (setq predicate
                (gnus-get-predicate
                 (gnus-agent-find-parameter group 'agent-predicate)))

          ;; If the selection predicate requires scoring, score each header
          (unless (memq predicate '(gnus-agent-true gnus-agent-false))
            (let ((score-param
                   (gnus-agent-find-parameter group 'agent-score-file)))
              ;; Translate score-param into real one
              (cond
               ((not score-param))
               ((eq score-param 'file)
                (setq score-param (gnus-all-score-files group)))
               ((stringp (car score-param)))
               (t
                (setq score-param (list (list score-param)))))
              (when score-param
                (gnus-score-headers score-param))))

          (unless (and (eq predicate 'gnus-agent-false)
                       (not marked-articles))
            (let ((arts (list nil)))
              (let ((arts-tail arts)
                    (alist (gnus-agent-load-alist group))
                    (marked-articles marked-articles)
                    (gnus-newsgroup-headers gnus-newsgroup-headers))
                (while (setq gnus-headers (pop gnus-newsgroup-headers))
                  (let ((num (mail-header-number gnus-headers)))
                    ;; Determine if this article is already in the cache
                    (while (and alist
                                (> num (caar alist)))
                      (setq alist (cdr alist)))

                    (unless (and (eq num (caar alist))
                                 (cdar alist))

                      ;; Determine if this article was marked for download.
                      (while (and marked-articles
                                  (> num (car marked-articles)))
                        (setq marked-articles
                              (cdr marked-articles)))

                      ;; When this article is marked, or selected by the
                      ;; predicate, add it to the download list
                      (when (or (eq num (car marked-articles))
                                (let ((gnus-score
                                       (or (cdr
					    (assq num gnus-newsgroup-scored))
                                           gnus-summary-default-score))
                                      (gnus-agent-long-article
                                       (gnus-agent-find-parameter
                                        group 'agent-long-article))
                                      (gnus-agent-short-article
                                       (gnus-agent-find-parameter
                                        group 'agent-short-article))
                                      (gnus-agent-low-score
                                       (gnus-agent-find-parameter
                                        group 'agent-low-score))
                                      (gnus-agent-high-score
                                       (gnus-agent-find-parameter
                                        group 'agent-high-score))
                                      (gnus-agent-expire-days
                                       (gnus-agent-find-parameter
                                        group 'agent-days-until-old)))
                                  (funcall predicate)))
                        (gnus-agent-append-to-list arts-tail num))))))

              (let (fetched-articles)
                ;; Fetch all selected articles
                (setq gnus-newsgroup-undownloaded
                      (gnus-sorted-ndifference
		       gnus-newsgroup-undownloaded
		       (setq fetched-articles
			     (if (cdr arts)
				 (gnus-agent-fetch-articles group (cdr arts))
			       nil))))

                (let ((unfetched-articles
		       (gnus-sorted-ndifference (cdr arts) fetched-articles)))
                  (if gnus-newsgroup-active
                      ;; Update the summary buffer
                      (progn
                        (dolist (article marked-articles)
                          (gnus-summary-set-agent-mark article t))
                        (dolist (article fetched-articles)
                          (when gnus-agent-mark-unread-after-downloaded
			    (setq gnus-newsgroup-downloadable
				  (delq article gnus-newsgroup-downloadable))
			    (gnus-summary-mark-article
			     article gnus-unread-mark))
                          (when (gnus-summary-goto-subject article nil t)
                            (gnus-summary-update-download-mark article)))
                        (dolist (article unfetched-articles)
                          (gnus-summary-mark-article
			   article gnus-canceled-mark)))

                    ;; Update the group buffer.

                    ;; When some, or all, of the marked articles came
                    ;; from the download mark.  Remove that mark.  I
                    ;; didn't do this earlier as I only want to remove
                    ;; the marks after the fetch is completed.

                    (dolist (mark gnus-agent-download-marks)
                      (when (eq mark 'download)
                        (let ((marked-arts
			       (assq mark (gnus-info-marks
					   (setq info (gnus-get-info group))))))
                          (when (cdr marked-arts)
                            ;; FIXME: Use `cl-callf'?
                            (setq marks
				  (delq marked-arts (gnus-info-marks info)))
                            (setf (gnus-info-marks info) marks)))))
                    (let ((read (gnus-info-read
				 (or info (setq info (gnus-get-info group))))))
                      (setf (gnus-info-read info)
                            (gnus-add-to-range read unfetched-articles)))

                    (gnus-group-update-group group t)
                    (sit-for 0)

                    (gnus-dribble-enter
                     (concat "(gnus-group-set-info '"
                             (gnus-prin1-to-string info)
                             ")")
		     (concat "^(gnus-group-set-info '(\""
			     (regexp-quote group) "\""))))))))))))

;;;
;;; Agent Category Mode
;;;

(defvar gnus-category-line-format "     %(%20c%): %g\n"
  "Format of category lines.

Valid specifiers include:
%c  Topic name (string)
%g  The number of groups in the topic (integer)

General format specifiers can also be used.  See Info node
`(gnus)Formatting Variables'.")

(defvar gnus-category-mode-line-format "Gnus: %%b"
  "The format specification for the category mode line.")

(defvar gnus-agent-predicate 'false
  "The selection predicate used when no other source is available.")


;;; Internal variables.

(defvar gnus-category-buffer "*Agent Category*")

(defvar gnus-tmp-name)
(defvar gnus-tmp-groups)

(defvar gnus-category-line-format-alist
  '((?c gnus-tmp-name ?s)
    (?g gnus-tmp-groups ?d)))

(defvar gnus-category-mode-line-format-alist
  '((?u user-defined ?s)))

(defvar gnus-category-line-format-spec nil)
(defvar gnus-category-mode-line-format-spec nil)

(defvar gnus-category-mode-map nil)

(unless gnus-category-mode-map
  (setq gnus-category-mode-map (make-sparse-keymap))
  (suppress-keymap gnus-category-mode-map)

  (gnus-define-keys gnus-category-mode-map
    "q" gnus-category-exit
    "k" gnus-category-kill
    "c" gnus-category-copy
    "a" gnus-category-add
    "e" gnus-agent-customize-category
    "p" gnus-category-edit-predicate
    "g" gnus-category-edit-groups
    "s" gnus-category-edit-score
    "l" gnus-category-list

    "\C-c\C-i" gnus-info-find-node
    "\C-c\C-b" gnus-bug))

(defcustom gnus-category-menu-hook nil
  "Hook run after the creation of the menu."
  :group 'gnus-agent
  :type 'hook)

(defun gnus-category-make-menu-bar ()
  (gnus-turn-off-edit-menu 'category)
  (unless (boundp 'gnus-category-menu)
    (easy-menu-define
     gnus-category-menu gnus-category-mode-map ""
     '("Categories"
       ["Add" gnus-category-add t]
       ["Kill" gnus-category-kill t]
       ["Copy" gnus-category-copy t]
       ["Edit category" gnus-agent-customize-category t]
       ["Edit predicate" gnus-category-edit-predicate t]
       ["Edit score" gnus-category-edit-score t]
       ["Edit groups" gnus-category-edit-groups t]
       ["Exit" gnus-category-exit t]))

    (gnus-run-hooks 'gnus-category-menu-hook)))

(define-derived-mode gnus-category-mode gnus-mode "Category"
  "Major mode for listing and editing agent categories.
All normal editing commands are switched off.
\\<gnus-category-mode-map>
For more in-depth information on this mode, read the manual
\(`\\[gnus-info-find-node]').

The following commands are available:

\\{gnus-category-mode-map}"
  (when (gnus-visual-p 'category-menu 'menu)
    (gnus-category-make-menu-bar))
  (gnus-simplify-mode-line)
  (gnus-set-default-directory)
  (setq mode-line-process nil)
  (buffer-disable-undo)
  (setq truncate-lines t))

(defalias 'gnus-category-position-point 'gnus-goto-colon)

(defun gnus-category-insert-line (category)
  (let* ((gnus-tmp-name (format "%s" (car category)))
	 (gnus-tmp-groups (length (gnus-agent-cat-groups category))))
    (beginning-of-line)
    (add-text-properties
     (point)
     (prog1 (1+ (point))
       ;; Insert the text.
       (eval gnus-category-line-format-spec))
     (list 'gnus-category gnus-tmp-name))))

(defun gnus-enter-category-buffer ()
  "Go to the Category buffer."
  (interactive)
  (gnus-category-setup-buffer)
  (gnus-configure-windows 'category)
  (gnus-category-prepare))

(defun gnus-category-setup-buffer ()
  (unless (get-buffer gnus-category-buffer)
    (with-current-buffer (gnus-get-buffer-create gnus-category-buffer)
      (gnus-category-mode))))

(defun gnus-category-prepare ()
  (gnus-set-format 'category-mode)
  (gnus-set-format 'category t)
  (let ((alist gnus-category-alist)
	(buffer-read-only nil))
    (erase-buffer)
    (while alist
      (gnus-category-insert-line (pop alist)))
    (goto-char (point-min))
    (gnus-category-position-point)))

(defun gnus-category-name ()
  (or (intern (get-text-property (point-at-bol) 'gnus-category))
      (error "No category on the current line")))

(defun gnus-category-read ()
  "Read the category alist."
  (setq gnus-category-alist
        (or
	 (let ((list
		(with-temp-buffer
		  (ignore-errors
		    (nnheader-insert-file-contents (nnheader-concat gnus-agent-directory "lib/categories"))
		    (goto-char (point-min))
		    ;; This code isn't temp, it will be needed so long as
		    ;; anyone may be migrating from an older version.

		    ;; Once we're certain that people will not revert to an
		    ;; earlier version, we can take out the old-list code in
		    ;; gnus-category-write.
		    (let* ((old-list (read (current-buffer)))
			   (new-list (ignore-errors (read (current-buffer)))))
		      (if new-list
			  new-list
			;; Convert from a positional list to an alist.
			(mapcar
			 (lambda (c)
			   (setcdr c
				   (delq nil
					 (gnus-mapcar
					  (lambda (valu symb)
					    (if valu
						(cons symb valu)))
					  (cdr c)
					  '(agent-predicate agent-score-file agent-groups))))
			   c)
			 old-list)))))))
	   ;; Possibly decode group names.
	   (dolist (cat list)
	     (setf (alist-get 'agent-groups cat)
		   (mapcar (lambda (g)
			     (if (string-match-p "[^[:ascii:]]" g)
				 (decode-coding-string g 'utf-8-emacs)
			       g))
			   (alist-get 'agent-groups cat))))
	   list)
         (list (gnus-agent-cat-make 'default 'short)))))

(defun gnus-category-write ()
  "Write the category alist."
  (setq gnus-category-predicate-cache nil
	gnus-category-group-cache nil)
  ;; Temporarily encode non-ascii group names when saving to file,
  ;; pending an upgrade of Gnus' file formats.
  (let ((gnus-category-alist
	 (mapcar (lambda (cat)
		   (setf (alist-get 'agent-groups cat)
			 (mapcar (lambda (g)
				   (if (multibyte-string-p g)
				       (encode-coding-string g 'utf-8-emacs)
				     g))
				 (alist-get 'agent-groups cat)))
		   cat)
		 (copy-tree gnus-category-alist))))
   (gnus-make-directory (nnheader-concat gnus-agent-directory "lib"))
   (with-temp-file (nnheader-concat gnus-agent-directory "lib/categories")
     ;; This prin1 is temporary.  It exists so that people can revert
     ;; to an earlier version of gnus-agent.
     (prin1 (mapcar (lambda (c)
		      (list (car c)
			    (cdr (assoc 'agent-predicate c))
			    (cdr (assoc 'agent-score-file c))
			    (cdr (assoc 'agent-groups c))))
                    gnus-category-alist)
            (current-buffer))
     (newline)
     (prin1 gnus-category-alist (current-buffer)))))

(defun gnus-category-edit-predicate (category)
  "Edit the predicate for CATEGORY."
  (interactive (list (gnus-category-name)))
  (let ((info (assq category gnus-category-alist)))
    (gnus-edit-form
     (gnus-agent-cat-predicate info)
     (format "Editing the select predicate for category %s" category)
     `(lambda (predicate)
        ;; Avoid run-time execution of setf form
        ;; (setf (gnus-agent-cat-predicate (assq ',category gnus-category-alist))
        ;;       predicate)
        ;; use its expansion instead:
        (gnus-agent-cat-set-property (assq ',category gnus-category-alist)
                                     'agent-predicate predicate)

	(gnus-category-write)
	(gnus-category-list)))))

(defun gnus-category-edit-score (category)
  "Edit the score expression for CATEGORY."
  (interactive (list (gnus-category-name)))
  (let ((info (assq category gnus-category-alist)))
    (gnus-edit-form
     (gnus-agent-cat-score-file info)
     (format "Editing the score expression for category %s" category)
     `(lambda (score-file)
        ;; Avoid run-time execution of setf form
        ;; (setf (gnus-agent-cat-score-file (assq ',category gnus-category-alist))
        ;;       score-file)
        ;; use its expansion instead:
        (gnus-agent-cat-set-property (assq ',category gnus-category-alist)
                                     'agent-score-file score-file)

	(gnus-category-write)
	(gnus-category-list)))))

(defun gnus-category-edit-groups (category)
  "Edit the group list for CATEGORY."
  (interactive (list (gnus-category-name)))
  (let ((info (assq category gnus-category-alist)))
    (gnus-edit-form
     (gnus-agent-cat-groups info)
     (format "Editing the group list for category %s" category)
     `(lambda (groups)
        ;; Avoid run-time execution of setf form
        ;; (setf (gnus-agent-cat-groups (assq ',category gnus-category-alist))
        ;;       groups)
        ;; use its expansion instead:
        (gnus-agent-set-cat-groups (assq ',category gnus-category-alist)
                                   groups)

	(gnus-category-write)
	(gnus-category-list)))))

(defun gnus-category-kill (category)
  "Kill the current category."
  (interactive (list (gnus-category-name)))
  (let ((info (assq category gnus-category-alist))
	(buffer-read-only nil))
    (gnus-delete-line)
    (setq gnus-category-alist (delq info gnus-category-alist))
    (gnus-category-write)))

(defun gnus-category-copy (category to)
  "Copy the current category."
  (interactive (list (gnus-category-name) (intern (read-string "New name: "))))
  (let ((info (assq category gnus-category-alist)))
    (push (let ((newcat (copy-tree info)))
            (setf (gnus-agent-cat-name newcat) to)
            (setf (gnus-agent-cat-groups newcat) nil)
            newcat)
	  gnus-category-alist)
    (gnus-category-write)
    (gnus-category-list)))

(defun gnus-category-add (category)
  "Create a new category."
  (interactive "SCategory name: ")
  (when (assq category gnus-category-alist)
    (error "Category %s already exists" category))
  (push (gnus-agent-cat-make category)
	gnus-category-alist)
  (gnus-category-write)
  (gnus-category-list))

(defun gnus-category-list ()
  "List all categories."
  (interactive)
  (gnus-category-prepare))

(defun gnus-category-exit ()
  "Return to the group buffer."
  (interactive)
  (kill-buffer (current-buffer))
  (gnus-configure-windows 'group t))

;; To avoid having 8-bit characters in the source file.
(defvar gnus-category-not (list '! 'not (intern (format "%c" 172))))

(defvar gnus-category-predicate-alist
  '((spam . gnus-agent-spam-p)
    (short . gnus-agent-short-p)
    (long . gnus-agent-long-p)
    (low . gnus-agent-low-scored-p)
    (high . gnus-agent-high-scored-p)
    (read . gnus-agent-read-p)
    (true . gnus-agent-true)
    (false . gnus-agent-false))
  "Mapping from short score predicate symbols to predicate functions.")

(defun gnus-agent-spam-p ()
  "Say whether an article is spam or not."
  (unless gnus-agent-spam-hashtb
    (setq gnus-agent-spam-hashtb (gnus-make-hashtable 1000)))
  (if (not (equal (mail-header-references gnus-headers) ""))
      nil
    (let ((string (gnus-simplify-subject (mail-header-subject gnus-headers))))
      (prog1
	  (gethash string gnus-agent-spam-hashtb)
	(puthash string t gnus-agent-spam-hashtb)))))

(defun gnus-agent-short-p ()
  "Say whether an article is short or not."
  (< (mail-header-lines gnus-headers) gnus-agent-short-article))

(defun gnus-agent-long-p ()
  "Say whether an article is long or not."
  (> (mail-header-lines gnus-headers) gnus-agent-long-article))

(defun gnus-agent-low-scored-p ()
  "Say whether an article has a low score or not."
  (< gnus-score gnus-agent-low-score))

(defun gnus-agent-high-scored-p ()
  "Say whether an article has a high score or not."
  (> gnus-score gnus-agent-high-score))

(defun gnus-agent-read-p ()
  "Say whether an article is read or not."
  (gnus-member-of-range (mail-header-number gnus-headers)
			(gnus-info-read (gnus-get-info gnus-newsgroup-name))))

(defun gnus-category-make-function (predicate)
  "Make a function from PREDICATE."
  (let ((func (gnus-category-make-function-1 predicate)))
    (if (and (= (length func) 1)
	     (symbolp (car func)))
	(car func)
      (gnus-byte-compile `(lambda () ,func)))))

(defun gnus-agent-true ()
  "Return t."
  t)

(defun gnus-agent-false ()
  "Return nil."
  nil)

(defun gnus-category-make-function-1 (predicate)
  "Make a function from PREDICATE."
  (cond
   ;; Functions are just returned as is.
   ((or (symbolp predicate)
	(functionp predicate))
    `(,(or (cdr (assq predicate gnus-category-predicate-alist))
	   predicate)))
   ;; More complex predicate.
   ((consp predicate)
    `(,(cond
	((memq (car predicate) '(& and))
	 'and)
	((memq (car predicate) '(| or))
	 'or)
	((memq (car predicate) gnus-category-not)
	 'not))
      ,@(mapcar #'gnus-category-make-function-1 (cdr predicate))))
   (t
    (error "Unknown predicate type: %s" predicate))))

(defun gnus-get-predicate (predicate)
  "Return the function implementing PREDICATE."
  (or (cdr (assoc predicate gnus-category-predicate-cache))
      (let ((func (gnus-category-make-function predicate)))
	(push (cons predicate func) gnus-category-predicate-cache)
	func)))

(defun gnus-predicate-implies-unread (predicate)
  "Say whether PREDICATE implies unread articles only.
It is okay to miss some cases, but there must be no false positives.
That is, if this predicate returns true, then indeed the predicate must
return only unread articles."
  (eq t (gnus-function-implies-unread-1
         (gnus-category-make-function-1 predicate))))

(defun gnus-function-implies-unread-1 (function)
  "Recursively evaluate a predicate function to determine whether it can select
any read articles.  Returns t if the function is known to never
return read articles, nil when it is known to always return read
articles, and t_nil when the function may return both read and unread
articles."
  (let ((func (car function))
        (args (mapcar #'gnus-function-implies-unread-1 (cdr function))))
    (cond ((eq func 'and)
           (cond ((memq t args) ; if any argument returns only unread articles
                  ;; then that argument constrains the result to only unread articles.
                  t)
                 ((memq 't_nil args) ; if any argument is indeterminate
                  ;; then the result is indeterminate
                  't_nil)))
          ((eq func 'or)
           (cond ((memq nil args) ; if any argument returns read articles
                  ;; then that argument ensures that the results includes read articles.
                  nil)
                 ((memq 't_nil args) ; if any argument is indeterminate
                  ;; then that argument ensures that the results are indeterminate
                  't_nil)
                 (t ; if all arguments return only unread articles
                  ;; then the result returns only unread articles
                  t)))
          ((eq func 'not)
           (cond ((eq (car args) 't_nil) ; if the argument is indeterminate
                  ; then the result is indeterminate
                  (car args))
                 (t ; otherwise
                  ; toggle the result to be the opposite of the argument
                  (not (car args)))))
          ((eq func 'gnus-agent-read-p)
           nil) ; The read predicate NEVER returns unread articles
          ((eq func 'gnus-agent-false)
           t) ; The false predicate returns t as the empty set excludes all read articles
          ((eq func 'gnus-agent-true)
           nil) ; The true predicate ALWAYS returns read articles
          ((catch 'found-match
             (let ((alist gnus-category-predicate-alist))
               (while alist
                 (if (eq func (cdar alist))
                     (throw 'found-match t)
                   (setq alist (cdr alist))))))
           't_nil) ; All other predicates return read and unread articles
          (t
           (error "Unknown predicate function: %s" function)))))

(defun gnus-group-category (group)
  "Return the category GROUP belongs to."
  (unless gnus-category-group-cache
    (setq gnus-category-group-cache (gnus-make-hashtable 1000))
    (let ((cs gnus-category-alist)
	  groups)
      (dolist (cat cs)
	(setq groups (gnus-agent-cat-groups cat))
	(dolist (g groups)
	  (puthash g cat gnus-category-group-cache)))))
  (gethash group gnus-category-group-cache
	   (assq 'default gnus-category-alist)))

(defvar gnus-agent-expire-current-dirs)
(defvar gnus-agent-expire-stats)

(defun gnus-agent-expire-group (group &optional articles force)
  "Expire all old articles in GROUP.
If you want to force expiring of certain articles, this function can
take ARTICLES, and FORCE parameters as well.

The articles on which the expiration process runs are selected as follows:
  if ARTICLES is null, all read and unmarked articles.
  if ARTICLES is t, all articles.
  if ARTICLES is a list, just those articles.
FORCE is equivalent to setting the expiration predicates to true."
  (interactive (list (gnus-agent-read-group)))

  (if (not group)
      (gnus-agent-expire articles group force)
    (let (;; Bind gnus-agent-expire-stats to enable tracking of
	  ;; expiration statistics of this single group
          (gnus-agent-expire-stats (list 0 0 0.0)))
      (if (or (not (eq articles t))
              (yes-or-no-p
               (concat "Are you sure that you want to "
                       "expire all articles in " group "? ")))
          (let ((gnus-command-method (gnus-find-method-for-group group))
                (overview (gnus-get-buffer-create " *expire overview*"))
                orig)
            (unwind-protect
                (let ((active-file (gnus-agent-lib-file "active")))
                  (when (file-exists-p active-file)
                    (with-temp-buffer
                      (nnheader-insert-file-contents active-file)
                      (gnus-active-to-gnus-format
                       gnus-command-method
                       (setq orig (gnus-make-hashtable
                                   (count-lines (point-min) (point-max))))))
                    (save-excursion
                      (gnus-agent-expire-group-1
                       group overview (gethash group orig)
                       articles force))))
              (kill-buffer overview))))
      (gnus-message 4 "%s" (gnus-agent-expire-done-message)))))

(defun gnus-agent-expire-group-1 (group overview active articles force)
  ;; Internal function - requires caller to have set
  ;; gnus-command-method, initialized overview buffer, and to have
  ;; provided a non-nil active

  (let ((dir (gnus-agent-group-pathname group))
	(file-name-coding-system nnmail-pathname-coding-system))
    (gnus-agent-with-refreshed-group
     group
     (when (boundp 'gnus-agent-expire-current-dirs)
       (push dir gnus-agent-expire-current-dirs))

     (if (and (not force)
	      (eq 'DISABLE (gnus-agent-find-parameter group
						      'agent-enable-expiration)))
	 (gnus-message 5 "Expiry skipping over %s" group)
       (gnus-message 5 "Expiring articles in %s" group)
       (gnus-agent-load-alist group)
       (let* ((bytes-freed 0)
	      (size-files-deleted 0.0)
	      (files-deleted 0)
	      (nov-entries-deleted 0)
	      (info (gnus-get-info group))
	      (alist gnus-agent-article-alist)
	      (day (- (time-to-days nil)
		      (gnus-agent-find-parameter group 'agent-days-until-old)))
	      (specials (if (and alist
				 (not force))
			    ;; This could be a bit of a problem.  I need to
			    ;; keep the last article to avoid refetching
			    ;; headers when using nntp in the backend.  At
			    ;; the same time, if someone uses a backend
			    ;; that supports article moving then I may have
			    ;; to remove the last article to complete the
			    ;; move.  Right now, I'm going to assume that
			    ;; FORCE overrides specials.
			    (list (caar (last alist)))))
	      (unreads ;; Articles that are excluded from the
	       ;; expiration process
	       (cond (gnus-agent-expire-all
		      ;; All articles are marked read by global decree
		      nil)
		     ((eq articles t)
		      ;; All articles are marked read by function
		      ;; parameter
		      nil)
		     ((not articles)
		      ;; Unread articles are marked protected from
		      ;; expiration Don't call
		      ;; gnus-list-of-unread-articles as it returns
		      ;; articles that have not been fetched into the
		      ;; agent.
		      (ignore-errors
			(gnus-agent-unread-articles group)))
		     (t
		      ;; All articles EXCEPT those named by the caller
		      ;; are protected from expiration
		      (gnus-sorted-difference
		       (gnus-uncompress-range
			(cons (caar alist)
			      (caar (last alist))))
		       (sort articles '<)))))
	      (marked ;; More articles that are excluded from the
	       ;; expiration process
	       (cond (gnus-agent-expire-all
		      ;; All articles are unmarked by global decree
		      nil)
		     ((eq articles t)
		      ;; All articles are unmarked by function
		      ;; parameter
		      nil)
		     (articles
		      ;; All articles may as well be unmarked as the
		      ;; unreads list already names the articles we are
		      ;; going to keep
		      nil)
		     (t
		      ;; Ticked and/or dormant articles are excluded
		      ;; from expiration
		      (nconc
		       (gnus-uncompress-range
			(cdr (assq 'tick (gnus-info-marks info))))
		       (gnus-uncompress-range
			(cdr (assq 'dormant
				   (gnus-info-marks info))))))))
	      (nov-file (concat dir ".overview"))
	      (cnt 0)
	      (completed -1)
	      type

              ;; The normal article alist contains elements that look like
              ;; (article# .  fetch_date) I need to combine other
              ;; information with this list.  For example, a flag indicating
              ;; that a particular article MUST BE KEPT.  To do this, I'm
              ;; going to transform the elements to look like (article#
              ;; fetch_date keep_flag NOV_entry_position) Later, I'll reverse
              ;; the process to generate the expired article alist.
	      (dlist
               (nconc
                ;; Convert the alist elements to (article# fetch_date nil nil).
                (mapcar (lambda (e)
                          (list (car e) (cdr e) nil nil))
                        alist)

                ;; Convert the keep lists to elements that look like (article#
                ;; nil keep_flag nil) then append it to the expanded dlist
                ;; These statements are sorted by ascending precedence of the
                ;; keep_flag.
                (mapcar (lambda (e)
                          (list e nil 'unread  nil))
                        unreads)

                (mapcar (lambda (e)
                          (list e nil 'marked  nil))
                        marked)

                (mapcar (lambda (e)
                          (list e nil 'special nil))
                        specials))))

	 (set-buffer overview)
	 (erase-buffer)
	 (buffer-disable-undo)
	 (when (file-exists-p nov-file)
	   (gnus-message 7 "gnus-agent-expire: Loading overview...")
	   (nnheader-insert-file-contents nov-file)
	   (goto-char (point-min))

	   (let (p)
	     (while (< (setq p (point)) (point-max))
	       (condition-case nil
		   ;; If I successfully read an integer (the plus zero
		   ;; ensures a numeric type), append the position
		   ;; to the list
		   (push (list (+ 0 (read (current-buffer))) nil nil
			       p)
			 dlist)
		 (error
		  (gnus-message 1 "gnus-agent-expire: read error \
occurred when reading expression at %s in %s.  Skipping to next \
line." (point) nov-file)))
	       ;; Whether I succeeded, or failed, it doesn't matter.
	       ;; Move to the next line then try again.
	       (forward-line 1)))

	   (gnus-message
	    7 "gnus-agent-expire: Loading overview... Done"))
	 (set-buffer-modified-p nil)

	 ;; At this point, all of the information is in dlist.  The
	 ;; only problem is that much of it is spread across multiple
	 ;; entries.  Sort then MERGE!!
	 (gnus-message 7 "gnus-agent-expire: Sorting entries... ")
         (setq dlist
               (sort dlist
                     (lambda (a b)
                       (cond ((< (nth 0 a) (nth 0 b))
                              t)
                             ((> (nth 0 a) (nth 0 b))
                              nil)
                             (t
                              ;; If two entries have the same article-number
                              ;; then sort by ascending keep_flag.
                              (let* ((kf-score '((special . 0)
                                                 (marked . 1)
                                                 (unread . 2)))
                                     (a (or (cdr (assq (nth 2 a) kf-score))
                                            3))
                                     (b (or (cdr (assq (nth 2 b) kf-score))
                                            3)))
                                (<= a b)))))))
	 (gnus-message 7 "gnus-agent-expire: Sorting entries... Done")
	 (gnus-message 7 "gnus-agent-expire: Merging entries... ")
	 (let ((dlist dlist))
	   (while (cdr dlist)		; I'm not at the end-of-list
	     (if (eq (caar dlist) (caadr dlist))
		 (let ((first (cdr (car dlist)))
		       (secnd (cdr (cadr dlist))))
		   (setcar first (or (car first)
				     (car secnd))) ; fetch_date
		   (setq first (cdr first)
			 secnd (cdr secnd))
		   (setcar first (or (car first)
				     (car secnd))) ; Keep_flag
		   (setq first (cdr first)
			 secnd (cdr secnd))
		   (setcar first (or (car first)
				     (car secnd))) ; NOV_entry_position

		   (setcdr dlist (cddr dlist)))
	       (setq dlist (cdr dlist)))))

	 ;; Check the order of the entry positions.  They should be in
	 ;; ascending order.  If they aren't, the positions must be
	 ;; converted to markers.
	 (when (catch 'sort-results
		 (let ((dlist dlist)
		       (prev-pos -1)
		       pos)
		   (while dlist
		     (if (setq pos (nth 3 (pop dlist)))
			 (if (< pos prev-pos)
			     (throw 'sort-results 'unsorted)
			   (setq prev-pos pos))))))
	   (gnus-message 7 "gnus-agent-expire: Unsorted overview; inserting markers to compensate.")
	   (mapc (lambda (entry)
		     (let ((pos (nth 3 entry)))
		       (if pos
			   (setf (nth 3 entry)
				 (set-marker (make-marker)
					     pos)))))
		   dlist))

	 (gnus-message 7 "gnus-agent-expire: Merging entries... Done")

	 (let* ((len (float (length dlist)))
		(alist (list nil))
		(tail-alist alist)
		(position-offset 0)
		)

	   (while dlist
	     (let ((new-completed (truncate (* 100.0
					       (/ (setq cnt (1+ cnt))
						  len))))
		   message-log-max)
	       (when (> new-completed completed)
		 (setq completed new-completed)
		 (gnus-message 7 "%3d%% completed..."  completed)))
	     (let* ((entry          (car dlist))
		    (article-number (nth 0 entry))
		    (fetch-date     (nth 1 entry))
		    (keep           (nth 2 entry))
		    (marker         (nth 3 entry)))

	       (cond
		;; Kept articles are unread, marked, or special.
		(keep
		 (gnus-agent-message 10
				     "gnus-agent-expire: %s:%d: Kept %s article%s."
				     group article-number keep (if fetch-date " and file" ""))
		 (when fetch-date
		   (unless (file-exists-p
			    (concat dir (number-to-string
					 article-number)))
		     (setf (nth 1 entry) nil)
		     (gnus-agent-message 3 "gnus-agent-expire cleared \
download flag on %s:%d as the cached article file is missing."
					 group (caar dlist)))
		   (unless marker
		     (gnus-message 1 "gnus-agent-expire detected a \
missing NOV entry.  Run gnus-agent-regenerate-group to restore it.")))
		 (gnus-agent-append-to-list
		  tail-alist
		  (cons article-number fetch-date)))

		;; The following articles are READ, UNMARKED, and
		;; ORDINARY.  See if they can be EXPIRED!!!
		((setq type
		       (cond
			((not (integerp fetch-date))
			 'read)	;; never fetched article (may expire
			;; right now)
			((not (file-exists-p
			       (concat dir (number-to-string
					    article-number))))
			 (setf (nth 1 entry) nil)
			 'externally-expired) ;; Can't find the cached
			;; article.  Handle case
			;; as though this article
			;; was never fetched.

			;; We now have the arrival day, so we see
			;; whether it's old enough to be expired.
			((< fetch-date day)
			 'expired)
			(force
			 'forced)))

		 ;; I found some reason to expire this entry.

		 (let ((actions nil))
		   (when (memq type '(forced expired))
		     (ignore-errors	; Just being paranoid.
		       (let* ((file-name (nnheader-concat dir (number-to-string
							       article-number)))
			      (size (float (file-attribute-size
					    (file-attributes file-name)))))
			 (cl-incf bytes-freed size)
			 (cl-incf size-files-deleted size)
			 (cl-incf files-deleted)
			 (delete-file file-name))
		       (push "expired cached article" actions))
		     (setf (nth 1 entry) nil)
		     )

		   (when marker
		     (push "NOV entry removed" actions)

		     (goto-char (if (markerp marker)
				    marker
				  (- marker position-offset)))

		     (cl-incf nov-entries-deleted)

		     (let* ((from (point-at-bol))
			    (to (progn (forward-line 1) (point)))
			    (freed (- to from)))
		       (cl-incf bytes-freed freed)
		       (cl-incf position-offset freed)
		       (delete-region from to)))

		   ;; If considering all articles is set, I can only
		   ;; expire article IDs that are no longer in the
		   ;; active range (That is, articles that precede the
		   ;; first article in the new alist).
		   (if (and gnus-agent-consider-all-articles
			    (>= article-number (car active)))
		       ;; I have to keep this ID in the alist
		       (gnus-agent-append-to-list
			tail-alist (cons article-number fetch-date))
		     (push (format "Removed %s article number from \
article alist" type) actions))

		   (when actions
		     (gnus-agent-message 8 "gnus-agent-expire: %s:%d: %s"
					 group article-number
					 (mapconcat #'identity actions ", ")))))
		(t
		 (gnus-agent-message
		  10 "gnus-agent-expire: %s:%d: Article kept as \
expiration tests failed." group article-number)
		 (gnus-agent-append-to-list
		  tail-alist (cons article-number fetch-date)))
		)

	       ;; Remove markers as I intend to reuse this buffer again.
	       (when (and marker
			  (markerp marker))
		 (set-marker marker nil))

	       (setq dlist (cdr dlist))))

	   (setq alist (cdr alist))

	   (let ((inhibit-quit t))
	     (unless (equal alist gnus-agent-article-alist)
	       (setq gnus-agent-article-alist alist)
	       (gnus-agent-save-alist group))

	     (when (buffer-modified-p)
	       (let ((coding-system-for-write
		      gnus-agent-file-coding-system))
		 (gnus-make-directory dir)
		 (write-region (point-min) (point-max) nov-file nil
			       'silent)
		 ;; clear the modified flag as that I'm not confused by
		 ;; its status on the next pass through this routine.
		 (set-buffer-modified-p nil)
		 (gnus-agent-update-view-total-fetched-for group t)))

	     (when (eq articles t)
	       (gnus-summary-update-info))))

	 (when (boundp 'gnus-agent-expire-stats)
	   (let ((stats gnus-agent-expire-stats))
	     (cl-incf (nth 2 stats) bytes-freed)
	     (cl-incf (nth 1 stats) files-deleted)
	     (cl-incf (nth 0 stats) nov-entries-deleted)))

	 (gnus-agent-update-files-total-fetched-for group (- size-files-deleted)))))))

(defun gnus-agent-expire (&optional articles group force)
  "Expire all old articles.
If you want to force expiring of certain articles, this function can
take ARTICLES, GROUP and FORCE parameters as well.

The articles on which the expiration process runs are selected as follows:
  if ARTICLES is null, all read and unmarked articles.
  if ARTICLES is t, all articles.
  if ARTICLES is a list, just those articles.
Setting GROUP will limit expiration to that group.
FORCE is equivalent to setting the expiration predicates to true."
  (interactive)

  (if group
      (gnus-agent-expire-group group articles force)
    (if (or (not (eq articles t))
            (yes-or-no-p "Are you sure that you want to expire all \
articles in every agentized group? "))
        (let ((methods (gnus-agent-covered-methods))
              ;; Bind gnus-agent-expire-current-dirs to enable tracking
              ;; of agent directories.
              (gnus-agent-expire-current-dirs nil)
              ;; Bind gnus-agent-expire-stats to enable tracking of
              ;; expiration statistics across all groups
              (gnus-agent-expire-stats (list 0 0 0.0))
              gnus-command-method overview orig)
          (setq overview (gnus-get-buffer-create " *expire overview*"))
          (unwind-protect
              (while (setq gnus-command-method (pop methods))
                (let ((active-file (gnus-agent-lib-file "active")))
                  (when (file-exists-p active-file)
                    (with-temp-buffer
                      (nnheader-insert-file-contents active-file)
                      (gnus-active-to-gnus-format
                       gnus-command-method
                       (setq orig (gnus-make-hashtable
                                   (count-lines (point-min) (point-max))))))
                    (dolist (expiring-group (gnus-groups-from-server
                                             gnus-command-method))
                      (let ((active (gethash expiring-group orig)))
                        (when active
                          (save-excursion
                            (gnus-agent-expire-group-1
                             expiring-group overview active articles force))))))))
            (kill-buffer overview))
          (gnus-agent-expire-unagentized-dirs)
          (gnus-message 4 "%s" (gnus-agent-expire-done-message))))))

(defun gnus-agent-expire-done-message ()
  (if (and (> gnus-verbose 4)
           (boundp 'gnus-agent-expire-stats))
      (let* ((stats gnus-agent-expire-stats)
             (size (nth 2 stats))
            (units '(B KB MB GB)))
        (while (and (> size 1024.0)
                    (cdr units))
          (setq size (/ size 1024.0)
                units (cdr units)))

        (format "Expiry recovered %d NOV entries, deleted %d files,\
 and freed %.f %s."
                (nth 0 stats)
                (nth 1 stats)
                size (car units)))
    "Expiry...done"))

(defun gnus-agent-expire-unagentized-dirs ()
  (when (and gnus-agent-expire-unagentized-dirs
             (boundp 'gnus-agent-expire-current-dirs))
    (let ((file-name-coding-system nnmail-pathname-coding-system)
	  ;; Another hash table that could just be a list.
	  (keep (gnus-make-hashtable 20))
	  to-remove)
      (puthash gnus-agent-directory t keep)
      (dolist (dir gnus-agent-expire-current-dirs)
	(when (and (stringp dir)
		   (file-directory-p dir))
	  (while (not (gethash dir keep))
	    (puthash dir t keep)
	    (setq dir (file-name-directory (directory-file-name dir))))))

      (cl-labels ((checker
		   (d)
		   ;; Given a directory, check it and its subdirectories
		   ;; for membership in the keep list.  If it isn't found,
		   ;; add it to to-remove.
		   (let ((files (directory-files d))
			 file)
		     (while (setq file (pop files))
		       (cond ((equal file ".") ; Ignore self
			      nil)
			     ((equal file "..") ; Ignore parent
			      nil)
			     ((equal file ".overview")
			      ;; Directory must contain .overview to be
			      ;; agent's cache of a group.
			      (let ((d (file-name-as-directory d))
				    r)
				;; Search ancestors for last directory NOT
				;; found in keep.
				(while (not (gethash (setq d (file-name-directory d)) keep))
				  (setq r d
					d (directory-file-name d)))
				;; if ANY ancestor was NOT in keep hash and
				;; it's not already in to-remove, add it to
				;; to-remove.
				(if (and r
					 (not (member r to-remove)))
				    (push r to-remove))))
			     ((file-directory-p (setq file (nnheader-concat d file)))
			      (checker file)))))))
        (checker (expand-file-name gnus-agent-directory)))

      (when (and to-remove
                 (or gnus-expert-user
                     (gnus-y-or-n-p
                      "gnus-agent-expire has identified local directories that are\
 not currently required by any agentized group.  Do you wish to consider\
 deleting them?")))
        (while to-remove
          (let ((dir (pop to-remove)))
            (if (or gnus-expert-user
		    (gnus-y-or-n-p (format "Delete %s? " dir)))
                (let* (delete-recursive
		       files f
                       (delete-recursive
                        (function
                         (lambda (f-or-d)
                           (ignore-errors
                             (if (file-directory-p f-or-d)
                                 (condition-case nil
                                     (delete-directory f-or-d)
                                   (file-error
				    (setq files (directory-files f-or-d))
				    (while files
				      (setq f (pop files))
				      (or (member f '("." ".."))
					  (funcall delete-recursive
						   (nnheader-concat
						    f-or-d f))))
                                    (delete-directory f-or-d)))
                               (delete-file f-or-d)))))))
                  (funcall delete-recursive dir)))))))))

;;;###autoload
(defun gnus-agent-batch ()
  "Start Gnus, send queue and fetch session."
  (interactive)
  (let ((init-file-user "")
	(gnus-always-read-dribble-file t))
    (gnus))
  (let ((gnus-agent-confirmation-function 'gnus-agent-batch-confirmation))
    (gnus-group-send-queue)
    (gnus-agent-fetch-session)))

(defun gnus-agent-unread-articles (group)
  (let* ((read (gnus-info-read (gnus-get-info group)))
	 (known (gnus-agent-load-alist group))
	 (unread (list nil))
	 (tail-unread unread))
    (while (and known read)
      (let ((candidate (car (pop known))))
	(while (let* ((range (car read))
		      (min   (if (numberp range) range (car range)))
		      (max   (if (numberp range) range (cdr range))))
		 (cond ((or (not min)
			    (< candidate min))
			(gnus-agent-append-to-list tail-unread candidate)
			nil)
		       ((> candidate max)
			(setq read (cdr read))
                        ;; return t so that I always loop one more
                        ;; time.  If I just iterated off the end of
                        ;; read, min will become nil and the current
                        ;; candidate will be added to the unread list.
                        t))))))
    (while known
      (gnus-agent-append-to-list tail-unread (car (pop known))))
    (cdr unread)))

(defun gnus-agent-uncached-articles (articles group &optional cached-header)
  "Restrict ARTICLES to numbers already fetched.
Returns a sublist of ARTICLES that excludes those article ids in GROUP
that have already been fetched.
If CACHED-HEADER is nil, articles are only excluded if the article itself
has been fetched."

  ;; Logically equivalent to: (gnus-sorted-difference articles (mapcar
  ;; #'car gnus-agent-article-alist))

  ;; Functionally, I don't need to construct a temp list using mapcar.

  (if (and (or gnus-agent-cache (not gnus-plugged))
           (gnus-agent-load-alist group))
    (let* ((ref gnus-agent-article-alist)
           (arts articles)
           (uncached (list nil))
           (tail-uncached uncached))
      (while (and ref arts)
        (let ((v1 (car arts))
              (v2 (caar ref)))
          (cond ((< v1 v2) ; v1 does not appear in the reference list
		 (gnus-agent-append-to-list tail-uncached v1)
                 (setq arts (cdr arts)))
                ((= v1 v2)
                 (unless (or cached-header (cdar ref)) ; v1 is already cached
		   (gnus-agent-append-to-list tail-uncached v1))
                 (setq arts (cdr arts))
                 (setq ref (cdr ref)))
                (t ; reference article (v2) precedes the list being filtered
                 (setq ref (cdr ref))))))
      (while arts
	(gnus-agent-append-to-list tail-uncached (pop arts)))
      (cdr uncached))
    ;; if gnus-agent-load-alist fails, no articles are cached.
    articles))

(defun gnus-agent-retrieve-headers (articles group &optional fetch-old)
  (save-excursion
    (gnus-agent-create-buffer)
    (let ((gnus-decode-encoded-word-function 'identity)
	  (gnus-decode-encoded-address-function 'identity)
	  (file (gnus-agent-article-name ".overview" group))
          uncached-articles
	  (file-name-coding-system nnmail-pathname-coding-system))
      (gnus-make-directory (nnheader-translate-file-chars
			    (file-name-directory file) t))

      (when fetch-old
	(setq articles (gnus-uncompress-range
			(cons (if (numberp fetch-old)
				  (max 1 (- (car articles) fetch-old))
				1)
			      (car (last articles))))))

      ;; Populate temp buffer with known headers
      (when (file-exists-p file)
	(with-current-buffer gnus-agent-overview-buffer
	  (erase-buffer)
	  (let ((nnheader-file-coding-system
		 gnus-agent-file-coding-system))
	    (nnheader-insert-nov-file file (car articles)))))

      (if (setq uncached-articles (gnus-agent-uncached-articles articles group
                                                                t))
	  (progn
            ;; Populate nntp-server-buffer with uncached headers
	    (set-buffer nntp-server-buffer)
	    (erase-buffer)
            (cond ((not (eq 'nov (let (gnus-agent) ; Turn off agent
                                   (gnus-retrieve-headers
                                    uncached-articles group))))
                   (nnvirtual-convert-headers))
                  ((eq 'nntp (car gnus-current-select-method))
                   ;; The author of gnus-get-newsgroup-headers-xover
                   ;; reports that the XOVER command is commonly
                   ;; unreliable. The problem is that recently
                   ;; posted articles may not be entered into the
                   ;; NOV database in time to respond to my XOVER
                   ;; query.
                   ;;
                   ;; I'm going to use his assumption that the NOV
                   ;; database is updated in order of ascending
                   ;; article ID.  Therefore, a response containing
                   ;; article ID N implies that all articles from 1
                   ;; to N-1 are up-to-date.  Therefore, missing
                   ;; articles in that range have expired.

                   (set-buffer nntp-server-buffer)
                   (let* ((fetched-articles (list nil))
                          (tail-fetched-articles fetched-articles)
                          (min (car articles))
                          (max (car (last articles))))

                     ;; Get the list of articles that were fetched
                     (goto-char (point-min))
                     (let ((pm (point-max))
			   art)
                       (while (< (point) pm)
			 (when (setq art (gnus-agent-read-article-number))
                           (gnus-agent-append-to-list tail-fetched-articles art))
                         (forward-line 1)))

                     ;; Clip this list to the headers that will
                     ;; actually be returned
                     (setq fetched-articles (gnus-list-range-intersection
                                             (cdr fetched-articles)
                                             (cons min max)))

                     ;; Clip the uncached articles list to exclude
                     ;; IDs after the last FETCHED header.  The
                     ;; excluded IDs may be fetchable using HEAD.
                     (if (car tail-fetched-articles)
                         (setq uncached-articles
                               (gnus-list-range-intersection
                                uncached-articles
                                (cons (car uncached-articles)
                                      (car tail-fetched-articles)))))

                     ;; Create the list of articles that were
                     ;; "successfully" fetched.  Success, in this
                     ;; case, means that the ID should not be
                     ;; fetched again.  In the case of an expired
                     ;; article, the header will not be fetched.
                     (setq uncached-articles
                           (gnus-sorted-nunion fetched-articles
                                               uncached-articles))
                     )))

            ;; Erase the temp buffer
	    (set-buffer gnus-agent-overview-buffer)
	    (erase-buffer)

            ;; Copy the nntp-server-buffer to the temp buffer
	    (set-buffer nntp-server-buffer)
	    (copy-to-buffer gnus-agent-overview-buffer (point-min) (point-max))

	    ;; Merge the temp buffer with the known headers (found on
	    ;; disk in FILE) into the nntp-server-buffer
	    (when uncached-articles
	      (gnus-agent-braid-nov uncached-articles file))

	    ;; Save the new set of known headers to FILE
	    (set-buffer nntp-server-buffer)
	    (let ((coding-system-for-write
		   gnus-agent-file-coding-system))
	      (gnus-agent-check-overview-buffer)
	      (write-region (point-min) (point-max) file nil 'silent))

	    (gnus-agent-update-view-total-fetched-for group t)

            ;; Update the group's article alist to include the newly
            ;; fetched articles.
	    (gnus-agent-load-alist group)
	    (gnus-agent-save-alist group uncached-articles nil)
            )

        ;; Copy the temp buffer to the nntp-server-buffer
        (set-buffer nntp-server-buffer)
	(erase-buffer)
	(insert-buffer-substring gnus-agent-overview-buffer)))

    (if (and fetch-old
	     (not (numberp fetch-old)))
	t				; Don't remove anything.
      (nnheader-nov-delete-outside-range
       (car articles)
       (car (last articles)))
      t)

    'nov))

(defun gnus-agent-request-article (article group)
  "Retrieve ARTICLE in GROUP from the agent cache."
  (when (and gnus-agent
             (or gnus-agent-cache
                 (not gnus-plugged))
             (numberp article))
    (let* ((gnus-command-method (gnus-find-method-for-group group))
           (file (gnus-agent-article-name (number-to-string article) group))
           (buffer-read-only nil)
	   (file-name-coding-system nnmail-pathname-coding-system))
      (when (and (file-exists-p file)
                 (> (file-attribute-size (file-attributes file)) 0))
        (erase-buffer)
        (gnus-kill-all-overlays)
        (let ((coding-system-for-read gnus-cache-coding-system))
          (insert-file-contents file))
        t))))

(defun gnus-agent-store-article (article group)
  (let* ((gnus-command-method (gnus-find-method-for-group group))
	 (file (gnus-agent-article-name (number-to-string article) group))
	 (file-name-coding-system nnmail-pathname-coding-system)
	 (coding-system-for-write gnus-cache-coding-system))
    (when (not (file-exists-p file))
      (gnus-make-directory (file-name-directory file))
      (write-region (point-min) (point-max) file nil 'silent)
      ;; Tell the Agent when the article was fetched, so that it can
      ;; be expired later.
      (gnus-agent-load-alist group)
      (gnus-agent-save-alist group (list article)
			     (time-to-days nil)))))

(defun gnus-agent-regenerate-group (group &optional reread)
  "Regenerate GROUP.
If REREAD is t, all articles in the .overview are marked as unread.
If REREAD is a list, the specified articles will be marked as unread.
In addition, their NOV entries in .overview will be refreshed using
the articles' current headers.
If REREAD is not nil, downloaded articles are marked as unread."
  (interactive
   (list (gnus-agent-read-group)
         (catch 'mark
           (while (let (c
                        (cursor-in-echo-area t)
                        (echo-keystrokes 0))
                    (message "Mark as unread: (n)one / (a)ll / all (d)ownloaded articles? (n) ")
                    (setq c (read-char-exclusive))

                    (cond ((or (eq c ?\r) (eq c ?n) (eq c ?N))
                           (throw 'mark nil))
                          ((or (eq c ?a) (eq c ?A))
                           (throw 'mark t))
                          ((or (eq c ?d) (eq c ?D))
                           (throw 'mark 'some)))
                    (gnus-message 3 "Ignoring unexpected input")
                    (sit-for 1)
                    t)))))
  (when group
    (gnus-message 5 "Regenerating in %s" group)
    (let* ((gnus-command-method (or gnus-command-method
				    (gnus-find-method-for-group group)))
	   (file (gnus-agent-article-name ".overview" group))
	   (dir (file-name-directory file))
	   (file-name-coding-system nnmail-pathname-coding-system)
	   (downloaded (if (file-exists-p dir)
			   (sort (delq nil (mapcar (lambda (name)
						     (and (not (file-directory-p (nnheader-concat dir name)))
							  (string-to-number name)))
						   (directory-files
                                                    dir nil "\\`[0-9]+\\'" t)))
				 '>)
			 (progn (gnus-make-directory dir) nil)))
           nov-arts
	   alist header
	   regenerated)

      (mm-with-unibyte-buffer
	(if (file-exists-p file)
	    (let ((nnheader-file-coding-system
		   gnus-agent-file-coding-system))
	      (nnheader-insert-file-contents file)))
	(set-buffer-modified-p nil)

	;; Load the article IDs found in the overview file.  As a
	;; side-effect, validate the file contents.
	(let ((load t))
	  (while load
	    (setq load nil)
	    (goto-char (point-min))
	    (while (< (point) (point-max))
	      (cond ((and (looking-at "[0-9]+\t")
			  (<= (- (match-end 0) (match-beginning 0)) 9))
		     (push (read (current-buffer)) nov-arts)
		     (forward-line 1)
		     (let ((l1 (car nov-arts))
			   (l2 (cadr nov-arts)))
		       (cond ((and (listp reread) (memq l1 reread))
			      (gnus-delete-line)
			      (setq nov-arts (cdr nov-arts))
			      (gnus-message 4 "gnus-agent-regenerate-group: NOV\
 entry of article %s deleted." l1))
			     ((not l2)
			      nil)
			     ((< l1 l2)
			      (gnus-message 3 "gnus-agent-regenerate-group: NOV\
 entries are NOT in ascending order.")
			      ;; Don't sort now as I haven't verified
			      ;; that every line begins with a number
			      (setq load t))
			     ((= l1 l2)
			      (forward-line -1)
			      (gnus-message 4 "gnus-agent-regenerate-group: NOV\
 entries contained duplicate of article %s.	 Duplicate deleted." l1)
			      (gnus-delete-line)
			      (setq nov-arts (cdr nov-arts))))))
		    (t
		     (gnus-message 1 "gnus-agent-regenerate-group: NOV\
 entries contained line that did not begin with an article number.  Deleted\
 line.")
		     (gnus-delete-line))))
	    (when load
	      (gnus-message 5 "gnus-agent-regenerate-group: Sorting NOV\
 entries into ascending order.")
	      (sort-numeric-fields 1 (point-min) (point-max))
	      (setq nov-arts nil))))
	(gnus-agent-check-overview-buffer)

	;; Construct a new article alist whose nodes match every header
	;; in the .overview file.  As a side-effect, missing headers are
	;; reconstructed from the downloaded article file.
	(while (or downloaded nov-arts)
	  (cond ((and downloaded
		      (or (not nov-arts)
			  (> (car downloaded) (car nov-arts))))
		 ;; This entry is missing from the overview file
		 (gnus-message 3 "Regenerating NOV %s %d..."
			       group (car downloaded))
		 (let ((file (concat dir (number-to-string (car downloaded)))))
		   (mm-with-unibyte-buffer
		     (nnheader-insert-file-contents file)
		     (nnheader-remove-body)
		     (setq header (nnheader-parse-naked-head)))
		   (setf (mail-header-number header) (car downloaded))
		   (if nov-arts
		       (let ((key (concat "^" (int-to-string (car nov-arts))
					  "\t")))
			 (or (re-search-backward key nil t)
			     (re-search-forward key))
			 (forward-line 1))
		     (goto-char (point-min)))
		   (nnheader-insert-nov header))
		 (setq nov-arts (cons (car downloaded) nov-arts)))
		((eq (car downloaded) (car nov-arts))
		 ;; This entry in the overview has been downloaded
		 (push (cons (car downloaded)
			     (time-to-days
			      (file-attribute-modification-time
			       (file-attributes
				(concat dir (number-to-string
					     (car downloaded)))))))
		       alist)
		 (setq downloaded (cdr downloaded))
		 (setq nov-arts (cdr nov-arts)))
		(t
		 ;; This entry in the overview has not been downloaded
		 (push (cons (car nov-arts) nil) alist)
		 (setq nov-arts (cdr nov-arts)))))

	;; When gnus-agent-consider-all-articles is set,
	;; gnus-agent-regenerate-group should NOT remove article IDs from
	;; the alist.  Those IDs serve as markers to indicate that an
	;; attempt has been made to fetch that article's header.

	;; When gnus-agent-consider-all-articles is NOT set,
	;; gnus-agent-regenerate-group can remove the article ID of every
	;; article (with the exception of the last ID in the list - it's
	;; special) that no longer appears in the overview.  In this
	;; situation, the last article ID in the list implies that it,
	;; and every article ID preceding it, have been fetched from the
	;; server.

	(if gnus-agent-consider-all-articles
	    ;; Restore all article IDs that were not found in the overview file.
	    (let* ((n (cons nil alist))
		   (merged n)
		   (o (gnus-agent-load-alist group)))
	      (while o
		(let ((nID (caadr n))
		      (oID (caar o)))
		  (cond ((not nID)
			 (setq n (setcdr n (list (list oID))))
			 (setq o (cdr o)))
			((< oID nID)
			 (setcdr n (cons (list oID) (cdr n)))
			 (setq o (cdr o)))
			((= oID nID)
			 (setq o (cdr o))
			 (setq n (cdr n)))
			(t
			 (setq n (cdr n))))))
	      (setq alist (cdr merged)))
	  ;; Restore the last article ID if it is not already in the new alist
	  (let ((n (last alist))
		(o (last (gnus-agent-load-alist group))))
	    (cond ((not o)
		   nil)
		  ((not n)
		   (push (cons (caar o) nil) alist))
		  ((< (caar n) (caar o))
		   (setcdr n (list (car o)))))))

	(let ((inhibit-quit t))
	  (if (setq regenerated (buffer-modified-p))
	      (let ((coding-system-for-write gnus-agent-file-coding-system))
		(write-region (point-min) (point-max) file nil 'silent)))

	  (setq regenerated (or regenerated
				(and reread gnus-agent-article-alist)
				(not (equal alist gnus-agent-article-alist))))

	  (setq gnus-agent-article-alist alist)

	  (when regenerated
	    (gnus-agent-save-alist group)

	    ;; I have to alter the group's active range NOW as
	    ;; gnus-make-ascending-articles-unread will use it to
	    ;; recalculate the number of unread articles in the group

	    (let ((group (gnus-group-real-name group))
		  (group-active (or (gnus-active group)
				    (gnus-activate-group group))))
	      (gnus-agent-possibly-alter-active group group-active)))))

      (when (and reread gnus-agent-article-alist)
	(gnus-agent-synchronize-group-flags
	 group
	 (list (list
		(if (listp reread)
		    reread
		  (delq nil (mapcar (function (lambda (c)
						(cond ((eq reread t)
						       (car c))
						      ((cdr c)
						       (car c)))))
				    gnus-agent-article-alist)))
		'del '(read)))
	 gnus-command-method)

	(when regenerated
	  (gnus-agent-update-files-total-fetched-for group nil)))

      (gnus-message 5 "")
      regenerated)))

;;;###autoload
(defun gnus-agent-regenerate (&optional _clean reread)
  "Regenerate all agent covered files.
CLEAN is obsolete and ignored."
  (interactive)
  (let (regenerated)
    (gnus-message 4 "Regenerating Gnus agent files...")
    (dolist (gnus-command-method (gnus-agent-covered-methods))
      (dolist (group (gnus-groups-from-server gnus-command-method))
        (setq regenerated (or (gnus-agent-regenerate-group group reread)
                              regenerated))))
    (gnus-message 4 "Regenerating Gnus agent files...done")

    regenerated))

(defun gnus-agent-go-online (&optional force)
  "Switch servers into online status."
  (interactive (list t))
  (dolist (server gnus-opened-servers)
    (when (eq (nth 1 server) 'offline)
      (if (if (eq force 'ask)
	      (gnus-y-or-n-p
	       (format "Switch %s:%s into online status? "
		       (caar server) (cadar server)))
	    force)
	  (setcar (nthcdr 1 server) 'close)))))

(defun gnus-agent-toggle-group-plugged (group)
  "Toggle the status of the server of the current group."
  (interactive (list (gnus-group-group-name)))
  (let* ((method (gnus-find-method-for-group group))
	 (status (cadr (assoc method gnus-opened-servers))))
    (if (eq status 'offline)
	(gnus-server-set-status method 'closed)
      (gnus-close-server method)
      (gnus-server-set-status method 'offline))
    (message "Turn %s:%s from %s to %s." (car method) (cadr method)
	     (if (eq status 'offline) 'offline 'online)
	     (if (eq status 'offline) 'online 'offline))))

(defun gnus-agent-group-covered-p (group)
  (gnus-agent-method-p (gnus-group-method group)))

(defun gnus-agent-update-files-total-fetched-for (group delta
							&optional method path)
  "Update, or set, the total disk space used by the articles that the
agent has fetched."
  (when gnus-agent-total-fetched-hashtb
    (gnus-agent-with-refreshed-group
     group
     ;; if null, gnus-agent-group-pathname will calc method.
     (let* ((gnus-command-method method)
	    (path (or path (gnus-agent-group-pathname group)))
	    (entry (or (gethash path gnus-agent-total-fetched-hashtb)
		       (puthash path (make-list 3 0)
				     gnus-agent-total-fetched-hashtb)))
	    (file-name-coding-system nnmail-pathname-coding-system))
       (when (file-exists-p path)
	 (when (listp delta)
	   (if delta
	       (let ((sum 0.0)
		     file)
		 (while (setq file (pop delta))
		   (cl-incf sum (float (or (file-attribute-size
					    (file-attributes
					     (nnheader-concat
					      path
					      (if (numberp file)
						  (number-to-string file)
						file))))
					   0))))
		 (setq delta sum))
	     (let ((sum (- (nth 2 entry)))
		   (info (directory-files-and-attributes
			  path nil "\\`-?[0-9]+\\'" t))
		   file)
	       (while (setq file (pop info))
		 (cl-incf sum (float (or (file-attribute-size (cdr file)) 0))))
	       (setq delta sum))))

	 (setq gnus-agent-need-update-total-fetched-for t)
	 (cl-incf (nth 2 entry) delta))))))

(defun gnus-agent-update-view-total-fetched-for
    (group agent-over &optional method path)
  "Update, or set, the total disk space used by the .agentview and
.overview files.  These files are calculated separately as they can be
modified."
  (when gnus-agent-total-fetched-hashtb
    (gnus-agent-with-refreshed-group
     group
     ;; if null, gnus-agent-group-pathname will calc method.
     (let* ((gnus-command-method method)
	    (path (or path (gnus-agent-group-pathname group)))
	    (entry (or (gethash path gnus-agent-total-fetched-hashtb)
		       (puthash path (make-list 3 0)
				gnus-agent-total-fetched-hashtb)))
	    (file-name-coding-system nnmail-pathname-coding-system)
	    (size (or (file-attribute-size (file-attributes
					    (nnheader-concat
					     path (if agent-over
						      ".overview"
						    ".agentview"))))
		      0)))
       (setq gnus-agent-need-update-total-fetched-for t)
       (setf (nth (if agent-over 1 0) entry) size)))))

(defun gnus-agent-total-fetched-for (group &optional method no-inhibit)
  "Get the total disk space used by the specified GROUP."
  (unless (equal group "dummy.group")
    (unless gnus-agent-total-fetched-hashtb
      (setq gnus-agent-total-fetched-hashtb
	    (gnus-make-hashtable 1000)))

    ;; if null, gnus-agent-group-pathname will calc method.
    (let* ((gnus-command-method method)
	   (path (gnus-agent-group-pathname group))
	   (entry (gethash path gnus-agent-total-fetched-hashtb)))
      (if entry
	  (apply '+ entry)
	(let ((gnus-agent-inhibit-update-total-fetched-for (not no-inhibit)))
	  (+
	   (gnus-agent-update-view-total-fetched-for  group nil method path)
	   (gnus-agent-update-view-total-fetched-for  group t   method path)
	   (gnus-agent-update-files-total-fetched-for group nil method path)))))))

(provide 'gnus-agent)

;;; gnus-agent.el ends here

debug log:

solving cf705ae5dc ...
found cf705ae5dc in https://git.savannah.gnu.org/cgit/emacs.git

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

Code repositories for project(s) associated with this public inbox

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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).