summaryrefslogtreecommitdiff
path: root/sequencer.c
blob: 3031e7364d74e995297a7b8a72e04655c2ea3421 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
#include "cache.h"
#include "config.h"
#include "lockfile.h"
#include "sequencer.h"
#include "dir.h"
#include "object.h"
#include "commit.h"
#include "tag.h"
#include "run-command.h"
#include "exec_cmd.h"
#include "utf8.h"
#include "cache-tree.h"
#include "diff.h"
#include "revision.h"
#include "rerere.h"
#include "merge-recursive.h"
#include "refs.h"
#include "argv-array.h"
#include "quote.h"
#include "trailer.h"
#include "log-tree.h"
#include "wt-status.h"
#include "hashmap.h"
 
#define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 
const char sign_off_header[] = "Signed-off-by: ";
static const char cherry_picked_prefix[] = "(cherry picked from commit ";
 
GIT_PATH_FUNC(git_path_seq_dir, "sequencer")
 
static GIT_PATH_FUNC(git_path_todo_file, "sequencer/todo")
static GIT_PATH_FUNC(git_path_opts_file, "sequencer/opts")
static GIT_PATH_FUNC(git_path_head_file, "sequencer/head")
static GIT_PATH_FUNC(git_path_abort_safety_file, "sequencer/abort-safety")
 
static GIT_PATH_FUNC(rebase_path, "rebase-merge")
/*
 * The file containing rebase commands, comments, and empty lines.
 * This file is created by "git rebase -i" then edited by the user. As
 * the lines are processed, they are removed from the front of this
 * file and written to the tail of 'done'.
 */
static GIT_PATH_FUNC(rebase_path_todo, "rebase-merge/git-rebase-todo")
/*
 * The rebase command lines that have already been processed. A line
 * is moved here when it is first handled, before any associated user
 * actions.
 */
static GIT_PATH_FUNC(rebase_path_done, "rebase-merge/done")
/*
 * The file to keep track of how many commands were already processed (e.g.
 * for the prompt).
 */
static GIT_PATH_FUNC(rebase_path_msgnum, "rebase-merge/msgnum");
/*
 * The file to keep track of how many commands are to be processed in total
 * (e.g. for the prompt).
 */
static GIT_PATH_FUNC(rebase_path_msgtotal, "rebase-merge/end");
/*
 * The commit message that is planned to be used for any changes that
 * need to be committed following a user interaction.
 */
static GIT_PATH_FUNC(rebase_path_message, "rebase-merge/message")
/*
 * The file into which is accumulated the suggested commit message for
 * squash/fixup commands. When the first of a series of squash/fixups
 * is seen, the file is created and the commit message from the
 * previous commit and from the first squash/fixup commit are written
 * to it. The commit message for each subsequent squash/fixup commit
 * is appended to the file as it is processed.
 *
 * The first line of the file is of the form
 *     # This is a combination of $count commits.
 * where $count is the number of commits whose messages have been
 * written to the file so far (including the initial "pick" commit).
 * Each time that a commit message is processed, this line is read and
 * updated. It is deleted just before the combined commit is made.
 */
static GIT_PATH_FUNC(rebase_path_squash_msg, "rebase-merge/message-squash")
/*
 * If the current series of squash/fixups has not yet included a squash
 * command, then this file exists and holds the commit message of the
 * original "pick" commit.  (If the series ends without a "squash"
 * command, then this can be used as the commit message of the combined
 * commit without opening the editor.)
 */
static GIT_PATH_FUNC(rebase_path_fixup_msg, "rebase-merge/message-fixup")
/*
 * A script to set the GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
 * GIT_AUTHOR_DATE that will be used for the commit that is currently
 * being rebased.
 */
static GIT_PATH_FUNC(rebase_path_author_script, "rebase-merge/author-script")
/*
 * When an "edit" rebase command is being processed, the SHA1 of the
 * commit to be edited is recorded in this file.  When "git rebase
 * --continue" is executed, if there are any staged changes then they
 * will be amended to the HEAD commit, but only provided the HEAD
 * commit is still the commit to be edited.  When any other rebase
 * command is processed, this file is deleted.
 */
static GIT_PATH_FUNC(rebase_path_amend, "rebase-merge/amend")
/*
 * When we stop at a given patch via the "edit" command, this file contains
 * the abbreviated commit name of the corresponding patch.
 */
static GIT_PATH_FUNC(rebase_path_stopped_sha, "rebase-merge/stopped-sha")
/*
 * For the post-rewrite hook, we make a list of rewritten commits and
 * their new sha1s.  The rewritten-pending list keeps the sha1s of
 * commits that have been processed, but not committed yet,
 * e.g. because they are waiting for a 'squash' command.
 */
static GIT_PATH_FUNC(rebase_path_rewritten_list, "rebase-merge/rewritten-list")
static GIT_PATH_FUNC(rebase_path_rewritten_pending,
	"rebase-merge/rewritten-pending")
/*
 * The following files are written by git-rebase just after parsing the
 * command-line (and are only consumed, not modified, by the sequencer).
 */
static GIT_PATH_FUNC(rebase_path_gpg_sign_opt, "rebase-merge/gpg_sign_opt")
static GIT_PATH_FUNC(rebase_path_orig_head, "rebase-merge/orig-head")
static GIT_PATH_FUNC(rebase_path_verbose, "rebase-merge/verbose")
static GIT_PATH_FUNC(rebase_path_head_name, "rebase-merge/head-name")
static GIT_PATH_FUNC(rebase_path_onto, "rebase-merge/onto")
static GIT_PATH_FUNC(rebase_path_autostash, "rebase-merge/autostash")
static GIT_PATH_FUNC(rebase_path_strategy, "rebase-merge/strategy")
static GIT_PATH_FUNC(rebase_path_strategy_opts, "rebase-merge/strategy_opts")
static GIT_PATH_FUNC(rebase_path_allow_rerere_autoupdate, "rebase-merge/allow_rerere_autoupdate")
 
static inline int is_rebase_i(const struct replay_opts *opts)
{
	return opts->action == REPLAY_INTERACTIVE_REBASE;
}
 
static const char *get_dir(const struct replay_opts *opts)
{
	if (is_rebase_i(opts))
		return rebase_path();
	return git_path_seq_dir();
}
 
static const char *get_todo_path(const struct replay_opts *opts)
{
	if (is_rebase_i(opts))
		return rebase_path_todo();
	return git_path_todo_file();
}
 
/*
 * Returns 0 for non-conforming footer
 * Returns 1 for conforming footer
 * Returns 2 when sob exists within conforming footer
 * Returns 3 when sob exists within conforming footer as last entry
 */
static int has_conforming_footer(struct strbuf *sb, struct strbuf *sob,
	int ignore_footer)
{
	struct trailer_info info;
	int i;
	int found_sob = 0, found_sob_last = 0;
 
	trailer_info_get(&info, sb->buf);
 
	if (info.trailer_start == info.trailer_end)
		return 0;
 
	for (i = 0; i < info.trailer_nr; i++)
		if (sob && !strncmp(info.trailers[i], sob->buf, sob->len)) {
			found_sob = 1;
			if (i == info.trailer_nr - 1)
				found_sob_last = 1;
		}
 
	trailer_info_release(&info);
 
	if (found_sob_last)
		return 3;
	if (found_sob)
		return 2;
	return 1;
}
 
static const char *gpg_sign_opt_quoted(struct replay_opts *opts)
{
	static struct strbuf buf = STRBUF_INIT;
 
	strbuf_reset(&buf);
	if (opts->gpg_sign)
		sq_quotef(&buf, "-S%s", opts->gpg_sign);
	return buf.buf;
}
 
int sequencer_remove_state(struct replay_opts *opts)
{
	struct strbuf dir = STRBUF_INIT;
	int i;
 
	free(opts->gpg_sign);
	free(opts->strategy);
	for (i = 0; i < opts->xopts_nr; i++)
		free(opts->xopts[i]);
	free(opts->xopts);
 
	strbuf_addstr(&dir, get_dir(opts));
	remove_dir_recursively(&dir, 0);
	strbuf_release(&dir);
 
	return 0;
}
 
static const char *action_name(const struct replay_opts *opts)
{
	switch (opts->action) {
	case REPLAY_REVERT:
		return N_("revert");
	case REPLAY_PICK:
		return N_("cherry-pick");
	case REPLAY_INTERACTIVE_REBASE:
		return N_("rebase -i");
	}
	die(_("Unknown action: %d"), opts->action);
}
 
struct commit_message {
	char *parent_label;
	char *label;
	char *subject;
	const char *message;
};
 
static const char *short_commit_name(struct commit *commit)
{
	return find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV);
}
 
static int get_message(struct commit *commit, struct commit_message *out)
{
	const char *abbrev, *subject;
	int subject_len;
 
	out->message = logmsg_reencode(commit, NULL, get_commit_output_encoding());
	abbrev = short_commit_name(commit);
 
	subject_len = find_commit_subject(out->message, &subject);
 
	out->subject = xmemdupz(subject, subject_len);
	out->label = xstrfmt("%s... %s", abbrev, out->subject);
	out->parent_label = xstrfmt("parent of %s", out->label);
 
	return 0;
}
 
static void free_message(struct commit *commit, struct commit_message *msg)
{
	free(msg->parent_label);
	free(msg->label);
	free(msg->subject);
	unuse_commit_buffer(commit, msg->message);
}
 
static void print_advice(int show_hint, struct replay_opts *opts)
{
	char *msg = getenv("GIT_CHERRY_PICK_HELP");
 
	if (msg) {
		fprintf(stderr, "%s\n", msg);
		/*
		 * A conflict has occurred but the porcelain
		 * (typically rebase --interactive) wants to take care
		 * of the commit itself so remove CHERRY_PICK_HEAD
		 */
		unlink(git_path_cherry_pick_head());
		return;
	}
 
	if (show_hint) {
		if (opts->no_commit)
			advise(_("after resolving the conflicts, mark the corrected paths\n"
				 "with 'git add <paths>' or 'git rm <paths>'"));
		else
			advise(_("after resolving the conflicts, mark the corrected paths\n"
				 "with 'git add <paths>' or 'git rm <paths>'\n"
				 "and commit the result with 'git commit'"));
	}
}
 
static int write_message(const void *buf, size_t len, const char *filename,
			 int append_eol)
{
	static struct lock_file msg_file;
 
	int msg_fd = hold_lock_file_for_update(&msg_file, filename, 0);
	if (msg_fd < 0)
		return error_errno(_("could not lock '%s'"), filename);
	if (write_in_full(msg_fd, buf, len) < 0) {
		rollback_lock_file(&msg_file);
		return error_errno(_("could not write to '%s'"), filename);
	}
	if (append_eol && write(msg_fd, "\n", 1) < 0) {
		rollback_lock_file(&msg_file);
		return error_errno(_("could not write eol to '%s'"), filename);
	}
	if (commit_lock_file(&msg_file) < 0) {
		rollback_lock_file(&msg_file);
		return error(_("failed to finalize '%s'."), filename);
	}
 
	return 0;
}
 
/*
 * Reads a file that was presumably written by a shell script, i.e. with an
 * end-of-line marker that needs to be stripped.
 *
 * Note that only the last end-of-line marker is stripped, consistent with the
 * behavior of "$(cat path)" in a shell script.
 *
 * Returns 1 if the file was read, 0 if it could not be read or does not exist.
 */
static int read_oneliner(struct strbuf *buf,
	const char *path, int skip_if_empty)
{
	int orig_len = buf->len;
 
	if (!file_exists(path))
		return 0;
 
	if (strbuf_read_file(buf, path, 0) < 0) {
		warning_errno(_("could not read '%s'"), path);
		return 0;
	}
 
	if (buf->len > orig_len && buf->buf[buf->len - 1] == '\n') {
		if (--buf->len > orig_len && buf->buf[buf->len - 1] == '\r')
			--buf->len;
		buf->buf[buf->len] = '\0';
	}
 
	if (skip_if_empty && buf->len == orig_len)
		return 0;
 
	return 1;
}
 
static struct tree *empty_tree(void)
{
	return lookup_tree(&empty_tree_oid);
}
 
static int error_dirty_index(struct replay_opts *opts)
{
	if (read_cache_unmerged())
		return error_resolve_conflict(_(action_name(opts)));
 
	error(_("your local changes would be overwritten by %s."),
		_(action_name(opts)));
 
	if (advice_commit_before_merge)
		advise(_("commit your changes or stash them to proceed."));
	return -1;
}
 
static void update_abort_safety_file(void)
{
	struct object_id head;
 
	/* Do nothing on a single-pick */
	if (!file_exists(git_path_seq_dir()))
		return;
 
	if (!get_oid("HEAD", &head))
		write_file(git_path_abort_safety_file(), "%s", oid_to_hex(&head));
	else
		write_file(git_path_abort_safety_file(), "%s", "");
}
 
static int fast_forward_to(const struct object_id *to, const struct object_id *from,
			int unborn, struct replay_opts *opts)
{
	struct ref_transaction *transaction;
	struct strbuf sb = STRBUF_INIT;
	struct strbuf err = STRBUF_INIT;
 
	read_cache();
	if (checkout_fast_forward(from, to, 1))
		return -1; /* the callee should have complained already */
 
	strbuf_addf(&sb, _("%s: fast-forward"), _(action_name(opts)));
 
	transaction = ref_transaction_begin(&err);
	if (!transaction ||
	    ref_transaction_update(transaction, "HEAD",
				   to, unborn ? &null_oid : from,
				   0, sb.buf, &err) ||
	    ref_transaction_commit(transaction, &err)) {
		ref_transaction_free(transaction);
		error("%s", err.buf);
		strbuf_release(&sb);
		strbuf_release(&err);
		return -1;
	}
 
	strbuf_release(&sb);
	strbuf_release(&err);
	ref_transaction_free(transaction);
	update_abort_safety_file();
	return 0;
}
 
void append_conflicts_hint(struct strbuf *msgbuf)
{
	int i;
 
	strbuf_addch(msgbuf, '\n');
	strbuf_commented_addf(msgbuf, "Conflicts:\n");
	for (i = 0; i < active_nr;) {
		const struct cache_entry *ce = active_cache[i++];
		if (ce_stage(ce)) {
			strbuf_commented_addf(msgbuf, "\t%s\n", ce->name);
			while (i < active_nr && !strcmp(ce->name,
							active_cache[i]->name))
				i++;
		}
	}
}
 
static int do_recursive_merge(struct commit *base, struct commit *next,
			      const char *base_label, const char *next_label,
			      struct object_id *head, struct strbuf *msgbuf,
			      struct replay_opts *opts)
{
	struct merge_options o;
	struct tree *result, *next_tree, *base_tree, *head_tree;
	int clean;
	char **xopt;
	static struct lock_file index_lock;
 
	hold_locked_index(&index_lock, LOCK_DIE_ON_ERROR);
 
	read_cache();
 
	init_merge_options(&o);
	o.ancestor = base ? base_label : "(empty tree)";
	o.branch1 = "HEAD";
	o.branch2 = next ? next_label : "(empty tree)";
	if (is_rebase_i(opts))
		o.buffer_output = 2;
 
	head_tree = parse_tree_indirect(head);
	next_tree = next ? next->tree : empty_tree();
	base_tree = base ? base->tree : empty_tree();
 
	for (xopt = opts->xopts; xopt != opts->xopts + opts->xopts_nr; xopt++)
		parse_merge_opt(&o, *xopt);
 
	clean = merge_trees(&o,
			    head_tree,
			    next_tree, base_tree, &result);
	if (is_rebase_i(opts) && clean <= 0)
		fputs(o.obuf.buf, stdout);
	strbuf_release(&o.obuf);
	if (clean < 0)
		return clean;
 
	if (active_cache_changed &&
	    write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
		/*
		 * TRANSLATORS: %s will be "revert", "cherry-pick" or
		 * "rebase -i".
		 */
		return error(_("%s: Unable to write new index file"),
			_(action_name(opts)));
	rollback_lock_file(&index_lock);
 
	if (opts->signoff)
		append_signoff(msgbuf, 0, 0);
 
	if (!clean)
		append_conflicts_hint(msgbuf);
 
	return !clean;
}
 
static int is_index_unchanged(void)
{
	struct object_id head_oid;
	struct commit *head_commit;
 
	if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, head_oid.hash, NULL))
		return error(_("could not resolve HEAD commit\n"));
 
	head_commit = lookup_commit(&head_oid);
 
	/*
	 * If head_commit is NULL, check_commit, called from
	 * lookup_commit, would have indicated that head_commit is not
	 * a commit object already.  parse_commit() will return failure
	 * without further complaints in such a case.  Otherwise, if
	 * the commit is invalid, parse_commit() will complain.  So
	 * there is nothing for us to say here.  Just return failure.
	 */
	if (parse_commit(head_commit))
		return -1;
 
	if (!active_cache_tree)
		active_cache_tree = cache_tree();
 
	if (!cache_tree_fully_valid(active_cache_tree))
		if (cache_tree_update(&the_index, 0))
			return error(_("unable to update cache tree\n"));
 
	return !oidcmp(&active_cache_tree->oid,
		       &head_commit->tree->object.oid);
}
 
static int write_author_script(const char *message)
{
	struct strbuf buf = STRBUF_INIT;
	const char *eol;
	int res;
 
	for (;;)
		if (!*message || starts_with(message, "\n")) {
missing_author:
			/* Missing 'author' line? */
			unlink(rebase_path_author_script());
			return 0;
		} else if (skip_prefix(message, "author ", &message))
			break;
		else if ((eol = strchr(message, '\n')))
			message = eol + 1;
		else
			goto missing_author;
 
	strbuf_addstr(&buf, "GIT_AUTHOR_NAME='");
	while (*message && *message != '\n' && *message != '\r')
		if (skip_prefix(message, " <", &message))
			break;
		else if (*message != '\'')
			strbuf_addch(&buf, *(message++));
		else
			strbuf_addf(&buf, "'\\\\%c'", *(message++));
	strbuf_addstr(&buf, "'\nGIT_AUTHOR_EMAIL='");
	while (*message && *message != '\n' && *message != '\r')
		if (skip_prefix(message, "> ", &message))
			break;
		else if (*message != '\'')
			strbuf_addch(&buf, *(message++));
		else
			strbuf_addf(&buf, "'\\\\%c'", *(message++));
	strbuf_addstr(&buf, "'\nGIT_AUTHOR_DATE='@");
	while (*message && *message != '\n' && *message != '\r')
		if (*message != '\'')
			strbuf_addch(&buf, *(message++));
		else
			strbuf_addf(&buf, "'\\\\%c'", *(message++));
	res = write_message(buf.buf, buf.len, rebase_path_author_script(), 1);
	strbuf_release(&buf);
	return res;
}
 
/*
 * Read a list of environment variable assignments (such as the author-script
 * file) into an environment block. Returns -1 on error, 0 otherwise.
 */
static int read_env_script(struct argv_array *env)
{
	struct strbuf script = STRBUF_INIT;
	int i, count = 0;
	char *p, *p2;
 
	if (strbuf_read_file(&script, rebase_path_author_script(), 256) <= 0)
		return -1;
 
	for (p = script.buf; *p; p++)
		if (skip_prefix(p, "'\\\\''", (const char **)&p2))
			strbuf_splice(&script, p - script.buf, p2 - p, "'", 1);
		else if (*p == '\'')
			strbuf_splice(&script, p-- - script.buf, 1, "", 0);
		else if (*p == '\n') {
			*p = '\0';
			count++;
		}
 
	for (i = 0, p = script.buf; i < count; i++) {
		argv_array_push(env, p);
		p += strlen(p) + 1;
	}
 
	return 0;
}
 
static const char staged_changes_advice[] =
N_("you have staged changes in your working tree\n"
"If these changes are meant to be squashed into the previous commit, run:\n"
"\n"
"  git commit --amend %s\n"
"\n"
"If they are meant to go into a new commit, run:\n"
"\n"
"  git commit %s\n"
"\n"
"In both cases, once you're done, continue with:\n"
"\n"
"  git rebase --continue\n");
 
#define ALLOW_EMPTY (1<<0)
#define EDIT_MSG    (1<<1)
#define AMEND_MSG   (1<<2)
#define CLEANUP_MSG (1<<3)
#define VERIFY_MSG  (1<<4)
 
/*
 * If we are cherry-pick, and if the merge did not result in
 * hand-editing, we will hit this commit and inherit the original
 * author date and name.
 *
 * If we are revert, or if our cherry-pick results in a hand merge,
 * we had better say that the current user is responsible for that.
 *
 * An exception is when run_git_commit() is called during an
 * interactive rebase: in that case, we will want to retain the
 * author metadata.
 */
static int run_git_commit(const char *defmsg, struct replay_opts *opts,
			  unsigned int flags)
{
	struct child_process cmd = CHILD_PROCESS_INIT;
	const char *value;
 
	cmd.git_cmd = 1;
 
	if (is_rebase_i(opts)) {
		if (!(flags & EDIT_MSG)) {
			cmd.stdout_to_stderr = 1;
			cmd.err = -1;
		}
 
		if (read_env_script(&cmd.env_array)) {
			const char *gpg_opt = gpg_sign_opt_quoted(opts);
 
			return error(_(staged_changes_advice),
				     gpg_opt, gpg_opt);
		}
	}
 
	argv_array_push(&cmd.args, "commit");
 
	if (!(flags & VERIFY_MSG))
		argv_array_push(&cmd.args, "-n");
	if ((flags & AMEND_MSG))
		argv_array_push(&cmd.args, "--amend");
	if (opts->gpg_sign)
		argv_array_pushf(&cmd.args, "-S%s", opts->gpg_sign);
	if (opts->signoff)
		argv_array_push(&cmd.args, "-s");
	if (defmsg)
		argv_array_pushl(&cmd.args, "-F", defmsg, NULL);
	if ((flags & CLEANUP_MSG))
		argv_array_push(&cmd.args, "--cleanup=strip");
	if ((flags & EDIT_MSG))
		argv_array_push(&cmd.args, "-e");
	else if (!(flags & CLEANUP_MSG) &&
		 !opts->signoff && !opts->record_origin &&
		 git_config_get_value("commit.cleanup", &value))
		argv_array_push(&cmd.args, "--cleanup=verbatim");
 
	if ((flags & ALLOW_EMPTY))
		argv_array_push(&cmd.args, "--allow-empty");
 
	if (opts->allow_empty_message)
		argv_array_push(&cmd.args, "--allow-empty-message");
 
	if (cmd.err == -1) {
		/* hide stderr on success */
		struct strbuf buf = STRBUF_INIT;
		int rc = pipe_command(&cmd,
				      NULL, 0,
				      /* stdout is already redirected */
				      NULL, 0,
				      &buf, 0);
		if (rc)
			fputs(buf.buf, stderr);
		strbuf_release(&buf);
		return rc;
	}
 
	return run_command(&cmd);
}
 
static int is_original_commit_empty(struct commit *commit)
{
	const struct object_id *ptree_oid;
 
	if (parse_commit(commit))
		return error(_("could not parse commit %s\n"),
			     oid_to_hex(&commit->object.oid));
	if (commit->parents) {
		struct commit *parent = commit->parents->item;
		if (parse_commit(parent))
			return error(_("could not parse parent commit %s\n"),
				oid_to_hex(&parent->object.oid));
		ptree_oid = &parent->tree->object.oid;
	} else {
		ptree_oid = &empty_tree_oid; /* commit is root */
	}
 
	return !oidcmp(ptree_oid, &commit->tree->object.oid);
}
 
/*
 * Do we run "git commit" with "--allow-empty"?
 */
static int allow_empty(struct replay_opts *opts, struct commit *commit)
{
	int index_unchanged, empty_commit;
 
	/*
	 * Three cases:
	 *
	 * (1) we do not allow empty at all and error out.
	 *
	 * (2) we allow ones that were initially empty, but
	 * forbid the ones that become empty;
	 *
	 * (3) we allow both.
	 */
	if (!opts->allow_empty)
		return 0; /* let "git commit" barf as necessary */
 
	index_unchanged = is_index_unchanged();
	if (index_unchanged < 0)
		return index_unchanged;
	if (!index_unchanged)
		return 0; /* we do not have to say --allow-empty */
 
	if (opts->keep_redundant_commits)
		return 1;
 
	empty_commit = is_original_commit_empty(commit);
	if (empty_commit < 0)
		return empty_commit;
	if (!empty_commit)
		return 0;
	else
		return 1;
}
 
/*
 * Note that ordering matters in this enum. Not only must it match the mapping
 * below, it is also divided into several sections that matter.  When adding
 * new commands, make sure you add it in the right section.
 */
enum todo_command {
	/* commands that handle commits */
	TODO_PICK = 0,
	TODO_REVERT,
	TODO_EDIT,
	TODO_REWORD,
	TODO_FIXUP,
	TODO_SQUASH,
	/* commands that do something else than handling a single commit */
	TODO_EXEC,
	/* commands that do nothing but are counted for reporting progress */
	TODO_NOOP,
	TODO_DROP,
	/* comments (not counted for reporting progress) */
	TODO_COMMENT
};
 
static struct {
	char c;
	const char *str;
} todo_command_info[] = {
	{ 'p', "pick" },
	{ 0,   "revert" },
	{ 'e', "edit" },
	{ 'r', "reword" },
	{ 'f', "fixup" },
	{ 's', "squash" },
	{ 'x', "exec" },
	{ 0,   "noop" },
	{ 'd', "drop" },
	{ 0,   NULL }
};
 
static const char *command_to_string(const enum todo_command command)
{
	if (command < TODO_COMMENT)
		return todo_command_info[command].str;
	die("Unknown command: %d", command);
}
 
static int is_noop(const enum todo_command command)
{
	return TODO_NOOP <= command;
}
 
static int is_fixup(enum todo_command command)
{
	return command == TODO_FIXUP || command == TODO_SQUASH;
}
 
static int update_squash_messages(enum todo_command command,
		struct commit *commit, struct replay_opts *opts)
{
	struct strbuf buf = STRBUF_INIT;
	int count, res;
	const char *message, *body;
 
	if (file_exists(rebase_path_squash_msg())) {
		struct strbuf header = STRBUF_INIT;
		char *eol, *p;
 
		if (strbuf_read_file(&buf, rebase_path_squash_msg(), 2048) <= 0)
			return error(_("could not read '%s'"),
				rebase_path_squash_msg());
 
		p = buf.buf + 1;
		eol = strchrnul(buf.buf, '\n');
		if (buf.buf[0] != comment_line_char ||
		    (p += strcspn(p, "0123456789\n")) == eol)
			return error(_("unexpected 1st line of squash message:"
				       "\n\n\t%.*s"),
				     (int)(eol - buf.buf), buf.buf);
		count = strtol(p, NULL, 10);
 
		if (count < 1)
			return error(_("invalid 1st line of squash message:\n"
				       "\n\t%.*s"),
				     (int)(eol - buf.buf), buf.buf);
 
		strbuf_addf(&header, "%c ", comment_line_char);
		strbuf_addf(&header,
			    _("This is a combination of %d commits."), ++count);
		strbuf_splice(&buf, 0, eol - buf.buf, header.buf, header.len);
		strbuf_release(&header);
	} else {
		struct object_id head;
		struct commit *head_commit;
		const char *head_message, *body;
 
		if (get_oid("HEAD", &head))
			return error(_("need a HEAD to fixup"));
		if (!(head_commit = lookup_commit_reference(&head)))
			return error(_("could not read HEAD"));
		if (!(head_message = get_commit_buffer(head_commit, NULL)))
			return error(_("could not read HEAD's commit message"));
 
		find_commit_subject(head_message, &body);
		if (write_message(body, strlen(body),
				  rebase_path_fixup_msg(), 0)) {
			unuse_commit_buffer(head_commit, head_message);
			return error(_("cannot write '%s'"),
				     rebase_path_fixup_msg());
		}
 
		count = 2;
		strbuf_addf(&buf, "%c ", comment_line_char);
		strbuf_addf(&buf, _("This is a combination of %d commits."),
			    count);
		strbuf_addf(&buf, "\n%c ", comment_line_char);
		strbuf_addstr(&buf, _("This is the 1st commit message:"));
		strbuf_addstr(&buf, "\n\n");
		strbuf_addstr(&buf, body);
 
		unuse_commit_buffer(head_commit, head_message);
	}
 
	if (!(message = get_commit_buffer(commit, NULL)))
		return error(_("could not read commit message of %s"),
			     oid_to_hex(&commit->object.oid));
	find_commit_subject(message, &body);
 
	if (command == TODO_SQUASH) {
		unlink(rebase_path_fixup_msg());
		strbuf_addf(&buf, "\n%c ", comment_line_char);
		strbuf_addf(&buf, _("This is the commit message #%d:"), count);
		strbuf_addstr(&buf, "\n\n");
		strbuf_addstr(&buf, body);
	} else if (command == TODO_FIXUP) {
		strbuf_addf(&buf, "\n%c ", comment_line_char);
		strbuf_addf(&buf, _("The commit message #%d will be skipped:"),
			    count);
		strbuf_addstr(&buf, "\n\n");
		strbuf_add_commented_lines(&buf, body, strlen(body));
	} else
		return error(_("unknown command: %d"), command);
	unuse_commit_buffer(commit, message);
 
	res = write_message(buf.buf, buf.len, rebase_path_squash_msg(), 0);
	strbuf_release(&buf);
	return res;
}
 
static void flush_rewritten_pending(void) {
	struct strbuf buf = STRBUF_INIT;
	struct object_id newoid;
	FILE *out;
 
	if (strbuf_read_file(&buf, rebase_path_rewritten_pending(), (GIT_MAX_HEXSZ + 1) * 2) > 0 &&
	    !get_oid("HEAD", &newoid) &&
	    (out = fopen_or_warn(rebase_path_rewritten_list(), "a"))) {
		char *bol = buf.buf, *eol;
 
		while (*bol) {
			eol = strchrnul(bol, '\n');
			fprintf(out, "%.*s %s\n", (int)(eol - bol),
					bol, oid_to_hex(&newoid));
			if (!*eol)
				break;
			bol = eol + 1;
		}
		fclose(out);
		unlink(rebase_path_rewritten_pending());
	}
	strbuf_release(&buf);
}
 
static void record_in_rewritten(struct object_id *oid,
		enum todo_command next_command) {
	FILE *out = fopen_or_warn(rebase_path_rewritten_pending(), "a");
 
	if (!out)
		return;
 
	fprintf(out, "%s\n", oid_to_hex(oid));
	fclose(out);
 
	if (!is_fixup(next_command))
		flush_rewritten_pending();
}
 
static int do_pick_commit(enum todo_command command, struct commit *commit,
		struct replay_opts *opts, int final_fixup)
{
	unsigned int flags = opts->edit ? EDIT_MSG : 0;
	const char *msg_file = opts->edit ? NULL : git_path_merge_msg();
	struct object_id head;
	struct commit *base, *next, *parent;
	const char *base_label, *next_label;
	struct commit_message msg = { NULL, NULL, NULL, NULL };
	struct strbuf msgbuf = STRBUF_INIT;
	int res, unborn = 0, allow;
 
	if (opts->no_commit) {
		/*
		 * We do not intend to commit immediately.  We just want to
		 * merge the differences in, so let's compute the tree
		 * that represents the "current" state for merge-recursive
		 * to work on.
		 */
		if (write_cache_as_tree(head.hash, 0, NULL))
			return error(_("your index file is unmerged."));
	} else {
		unborn = get_oid("HEAD", &head);
		if (unborn)
			oidcpy(&head, &empty_tree_oid);
		if (index_differs_from(unborn ? EMPTY_TREE_SHA1_HEX : "HEAD", 0, 0))
			return error_dirty_index(opts);
	}
	discard_cache();
 
	if (!commit->parents)
		parent = NULL;
	else if (commit->parents->next) {
		/* Reverting or cherry-picking a merge commit */
		int cnt;
		struct commit_list *p;
 
		if (!opts->mainline)
			return error(_("commit %s is a merge but no -m option was given."),
				oid_to_hex(&commit->object.oid));
 
		for (cnt = 1, p = commit->parents;
		     cnt != opts->mainline && p;
		     cnt++)
			p = p->next;
		if (cnt != opts->mainline || !p)
			return error(_("commit %s does not have parent %d"),
				oid_to_hex(&commit->object.oid), opts->mainline);
		parent = p->item;
	} else if (0 < opts->mainline)
		return error(_("mainline was specified but commit %s is not a merge."),
			oid_to_hex(&commit->object.oid));
	else
		parent = commit->parents->item;
 
	if (get_message(commit, &msg) != 0)
		return error(_("cannot get commit message for %s"),
			oid_to_hex(&commit->object.oid));
 
	if (opts->allow_ff && !is_fixup(command) &&
	    ((parent && !oidcmp(&parent->object.oid, &head)) ||
	     (!parent && unborn))) {
		if (is_rebase_i(opts))
			write_author_script(msg.message);
		res = fast_forward_to(&commit->object.oid, &head, unborn,
			opts);
		if (res || command != TODO_REWORD)
			goto leave;
		flags |= EDIT_MSG | AMEND_MSG;
		if (command == TODO_REWORD)
			flags |= VERIFY_MSG;
		msg_file = NULL;
		goto fast_forward_edit;
	}
	if (parent && parse_commit(parent) < 0)
		/* TRANSLATORS: The first %s will be a "todo" command like
		   "revert" or "pick", the second %s a SHA1. */
		return error(_("%s: cannot parse parent commit %s"),
			command_to_string(command),
			oid_to_hex(&parent->object.oid));
 
	/*
	 * "commit" is an existing commit.  We would want to apply
	 * the difference it introduces since its first parent "prev"
	 * on top of the current HEAD if we are cherry-pick.  Or the
	 * reverse of it if we are revert.
	 */
 
	if (command == TODO_REVERT) {
		base = commit;
		base_label = msg.label;
		next = parent;
		next_label = msg.parent_label;
		strbuf_addstr(&msgbuf, "Revert \"");
		strbuf_addstr(&msgbuf, msg.subject);
		strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
		strbuf_addstr(&msgbuf, oid_to_hex(&commit->object.oid));
 
		if (commit->parents && commit->parents->next) {
			strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
			strbuf_addstr(&msgbuf, oid_to_hex(&parent->object.oid));
		}
		strbuf_addstr(&msgbuf, ".\n");
	} else {
		const char *p;
 
		base = parent;
		base_label = msg.parent_label;
		next = commit;
		next_label = msg.label;
 
		/* Append the commit log message to msgbuf. */
		if (find_commit_subject(msg.message, &p))
			strbuf_addstr(&msgbuf, p);
 
		if (opts->record_origin) {
			strbuf_complete_line(&msgbuf);
			if (!has_conforming_footer(&msgbuf, NULL, 0))
				strbuf_addch(&msgbuf, '\n');
			strbuf_addstr(&msgbuf, cherry_picked_prefix);
			strbuf_addstr(&msgbuf, oid_to_hex(&commit->object.oid));
			strbuf_addstr(&msgbuf, ")\n");
		}
	}
 
	if (command == TODO_REWORD)
		flags |= EDIT_MSG | VERIFY_MSG;
	else if (is_fixup(command)) {
		if (update_squash_messages(command, commit, opts))
			return -1;
		flags |= AMEND_MSG;
		if (!final_fixup)
			msg_file = rebase_path_squash_msg();
		else if (file_exists(rebase_path_fixup_msg())) {
			flags |= CLEANUP_MSG;
			msg_file = rebase_path_fixup_msg();
		} else {
			const char *dest = git_path_squash_msg();
			unlink(dest);
			if (copy_file(dest, rebase_path_squash_msg(), 0666))
				return error(_("could not rename '%s' to '%s'"),
					     rebase_path_squash_msg(), dest);
			unlink(git_path_merge_msg());
			msg_file = dest;
			flags |= EDIT_MSG;
		}
	}
 
	if (is_rebase_i(opts) && write_author_script(msg.message) < 0)
		res = -1;
	else if (!opts->strategy || !strcmp(opts->strategy, "recursive") || command == TODO_REVERT) {
		res = do_recursive_merge(base, next, base_label, next_label,
					 &head, &msgbuf, opts);
		if (res < 0)
			return res;
		res |= write_message(msgbuf.buf, msgbuf.len,
				     git_path_merge_msg(), 0);
	} else {
		struct commit_list *common = NULL;
		struct commit_list *remotes = NULL;
 
		res = write_message(msgbuf.buf, msgbuf.len,
				    git_path_merge_msg(), 0);
 
		commit_list_insert(base, &common);
		commit_list_insert(next, &remotes);
		res |= try_merge_command(opts->strategy,
					 opts->xopts_nr, (const char **)opts->xopts,
					common, oid_to_hex(&head), remotes);
		free_commit_list(common);
		free_commit_list(remotes);
	}
	strbuf_release(&msgbuf);
 
	/*
	 * If the merge was clean or if it failed due to conflict, we write
	 * CHERRY_PICK_HEAD for the subsequent invocation of commit to use.
	 * However, if the merge did not even start, then we don't want to
	 * write it at all.
	 */
	if (command == TODO_PICK && !opts->no_commit && (res == 0 || res == 1) &&
	    update_ref(NULL, "CHERRY_PICK_HEAD", &commit->object.oid, NULL,
		       REF_NODEREF, UPDATE_REFS_MSG_ON_ERR))
		res = -1;
	if (command == TODO_REVERT && ((opts->no_commit && res == 0) || res == 1) &&
	    update_ref(NULL, "REVERT_HEAD", &commit->object.oid, NULL,
		       REF_NODEREF, UPDATE_REFS_MSG_ON_ERR))
		res = -1;
 
	if (res) {
		error(command == TODO_REVERT
		      ? _("could not revert %s... %s")
		      : _("could not apply %s... %s"),
		      short_commit_name(commit), msg.subject);
		print_advice(res == 1, opts);
		rerere(opts->allow_rerere_auto);
		goto leave;
	}
 
	allow = allow_empty(opts, commit);
	if (allow < 0) {
		res = allow;
		goto leave;
	} else if (allow)
		flags |= ALLOW_EMPTY;
	if (!opts->no_commit)
fast_forward_edit:
		res = run_git_commit(msg_file, opts, flags);
 
	if (!res && final_fixup) {
		unlink(rebase_path_fixup_msg());
		unlink(rebase_path_squash_msg());
	}
 
leave:
	free_message(commit, &msg);
	update_abort_safety_file();
 
	return res;
}
 
static int prepare_revs(struct replay_opts *opts)
{
	/*
	 * picking (but not reverting) ranges (but not individual revisions)
	 * should be done in reverse
	 */
	if (opts->action == REPLAY_PICK && !opts->revs->no_walk)
		opts->revs->reverse ^= 1;
 
	if (prepare_revision_walk(opts->revs))
		return error(_("revision walk setup failed"));
 
	if (!opts->revs->commits)
		return error(_("empty commit set passed"));
	return 0;
}
 
static int read_and_refresh_cache(struct replay_opts *opts)
{
	static struct lock_file index_lock;
	int index_fd = hold_locked_index(&index_lock, 0);
	if (read_index_preload(&the_index, NULL) < 0) {
		rollback_lock_file(&index_lock);
		return error(_("git %s: failed to read the index"),
			_(action_name(opts)));
	}
	refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
	if (the_index.cache_changed && index_fd >= 0) {
		if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK)) {
			rollback_lock_file(&index_lock);
			return error(_("git %s: failed to refresh the index"),
				_(action_name(opts)));
		}
	}
	rollback_lock_file(&index_lock);
	return 0;
}
 
struct todo_item {
	enum todo_command command;
	struct commit *commit;
	const char *arg;
	int arg_len;
	size_t offset_in_buf;
};
 
struct todo_list {
	struct strbuf buf;
	struct todo_item *items;
	int nr, alloc, current;
	int done_nr, total_nr;
	struct stat_data stat;
};
 
#define TODO_LIST_INIT { STRBUF_INIT }
 
static void todo_list_release(struct todo_list *todo_list)
{
	strbuf_release(&todo_list->buf);
	FREE_AND_NULL(todo_list->items);
	todo_list->nr = todo_list->alloc = 0;
}
 
static struct todo_item *append_new_todo(struct todo_list *todo_list)
{
	ALLOC_GROW(todo_list->items, todo_list->nr + 1, todo_list->alloc);
	return todo_list->items + todo_list->nr++;
}
 
static int parse_insn_line(struct todo_item *item, const char *bol, char *eol)
{
	struct object_id commit_oid;
	char *end_of_object_name;
	int i, saved, status, padding;
 
	/* left-trim */
	bol += strspn(bol, " \t");
 
	if (bol == eol || *bol == '\r' || *bol == comment_line_char) {
		item->command = TODO_COMMENT;
		item->commit = NULL;
		item->arg = bol;
		item->arg_len = eol - bol;
		return 0;
	}
 
	for (i = 0; i < TODO_COMMENT; i++)
		if (skip_prefix(bol, todo_command_info[i].str, &bol)) {
			item->command = i;
			break;
		} else if (bol[1] == ' ' && *bol == todo_command_info[i].c) {
			bol++;
			item->command = i;
			break;
		}
	if (i >= TODO_COMMENT)
		return -1;
 
	if (item->command == TODO_NOOP) {
		item->commit = NULL;
		item->arg = bol;
		item->arg_len = eol - bol;
		return 0;
	}
 
	/* Eat up extra spaces/ tabs before object name */
	padding = strspn(bol, " \t");
	if (!padding)
		return -1;
	bol += padding;
 
	if (item->command == TODO_EXEC) {
		item->arg = bol;
		item->arg_len = (int)(eol - bol);
		return 0;
	}
 
	end_of_object_name = (char *) bol + strcspn(bol, " \t\n");
	saved = *end_of_object_name;
	*end_of_object_name = '\0';
	status = get_oid(bol, &commit_oid);
	*end_of_object_name = saved;
 
	item->arg = end_of_object_name + strspn(end_of_object_name, " \t");
	item->arg_len = (int)(eol - item->arg);
 
	if (status < 0)
		return -1;
 
	item->commit = lookup_commit_reference(&commit_oid);
	return !item->commit;
}
 
static int parse_insn_buffer(char *buf, struct todo_list *todo_list)
{
	struct todo_item *item;
	char *p = buf, *next_p;
	int i, res = 0, fixup_okay = file_exists(rebase_path_done());
 
	for (i = 1; *p; i++, p = next_p) {
		char *eol = strchrnul(p, '\n');
 
		next_p = *eol ? eol + 1 /* skip LF */ : eol;
 
		if (p != eol && eol[-1] == '\r')
			eol--; /* strip Carriage Return */
 
		item = append_new_todo(todo_list);
		item->offset_in_buf = p - todo_list->buf.buf;
		if (parse_insn_line(item, p, eol)) {
			res = error(_("invalid line %d: %.*s"),
				i, (int)(eol - p), p);
			item->command = TODO_NOOP;
		}
 
		if (fixup_okay)
			; /* do nothing */
		else if (is_fixup(item->command))
			return error(_("cannot '%s' without a previous commit"),
				command_to_string(item->command));
		else if (!is_noop(item->command))
			fixup_okay = 1;
	}
 
	return res;
}
 
static int count_commands(struct todo_list *todo_list)
{
	int count = 0, i;
 
	for (i = 0; i < todo_list->nr; i++)
		if (todo_list->items[i].command != TODO_COMMENT)
			count++;
 
	return count;
}
 
static int read_populate_todo(struct todo_list *todo_list,
			struct replay_opts *opts)
{
	struct stat st;
	const char *todo_file = get_todo_path(opts);
	int fd, res;
 
	strbuf_reset(&todo_list->buf);
	fd = open(todo_file, O_RDONLY);
	if (fd < 0)
		return error_errno(_("could not open '%s'"), todo_file);
	if (strbuf_read(&todo_list->buf, fd, 0) < 0) {
		close(fd);
		return error(_("could not read '%s'."), todo_file);
	}
	close(fd);
 
	res = stat(todo_file, &st);
	if (res)
		return error(_("could not stat '%s'"), todo_file);
	fill_stat_data(&todo_list->stat, &st);
 
	res = parse_insn_buffer(todo_list->buf.buf, todo_list);
	if (res) {
		if (is_rebase_i(opts))
			return error(_("please fix this using "
				       "'git rebase --edit-todo'."));
		return error(_("unusable instruction sheet: '%s'"), todo_file);
	}
 
	if (!todo_list->nr &&
	    (!is_rebase_i(opts) || !file_exists(rebase_path_done())))
		return error(_("no commits parsed."));
 
	if (!is_rebase_i(opts)) {
		enum todo_command valid =
			opts->action == REPLAY_PICK ? TODO_PICK : TODO_REVERT;
		int i;
 
		for (i = 0; i < todo_list->nr; i++)
			if (valid == todo_list->items[i].command)
				continue;
			else if (valid == TODO_PICK)
				return error(_("cannot cherry-pick during a revert."));
			else
				return error(_("cannot revert during a cherry-pick."));
	}
 
	if (is_rebase_i(opts)) {
		struct todo_list done = TODO_LIST_INIT;
		FILE *f = fopen_or_warn(rebase_path_msgtotal(), "w");
 
		if (strbuf_read_file(&done.buf, rebase_path_done(), 0) > 0 &&
				!parse_insn_buffer(done.buf.buf, &done))
			todo_list->done_nr = count_commands(&done);
		else
			todo_list->done_nr = 0;
 
		todo_list->total_nr = todo_list->done_nr
			+ count_commands(todo_list);
		todo_list_release(&done);
 
		if (f) {
			fprintf(f, "%d\n", todo_list->total_nr);
			fclose(f);
		}
	}
 
	return 0;
}
 
static int git_config_string_dup(char **dest,
				 const char *var, const char *value)
{
	if (!value)
		return config_error_nonbool(var);
	free(*dest);
	*dest = xstrdup(value);
	return 0;
}
 
static int populate_opts_cb(const char *key, const char *value, void *data)
{
	struct replay_opts *opts = data;
	int error_flag = 1;
 
	if (!value)
		error_flag = 0;
	else if (!strcmp(key, "options.no-commit"))
		opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.edit"))
		opts->edit = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.signoff"))
		opts->signoff = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.record-origin"))
		opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.allow-ff"))
		opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.mainline"))
		opts->mainline = git_config_int(key, value);
	else if (!strcmp(key, "options.strategy"))
		git_config_string_dup(&opts->strategy, key, value);
	else if (!strcmp(key, "options.gpg-sign"))
		git_config_string_dup(&opts->gpg_sign, key, value);
	else if (!strcmp(key, "options.strategy-option")) {
		ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
		opts->xopts[opts->xopts_nr++] = xstrdup(value);
	} else if (!strcmp(key, "options.allow-rerere-auto"))
		opts->allow_rerere_auto =
			git_config_bool_or_int(key, value, &error_flag) ?
				RERERE_AUTOUPDATE : RERERE_NOAUTOUPDATE;
	else
		return error(_("invalid key: %s"), key);
 
	if (!error_flag)
		return error(_("invalid value for %s: %s"), key, value);
 
	return 0;
}
 
static void read_strategy_opts(struct replay_opts *opts, struct strbuf *buf)
{
	int i;
 
	strbuf_reset(buf);
	if (!read_oneliner(buf, rebase_path_strategy(), 0))
		return;
	opts->strategy = strbuf_detach(buf, NULL);
	if (!read_oneliner(buf, rebase_path_strategy_opts(), 0))
		return;
 
	opts->xopts_nr = split_cmdline(buf->buf, (const char ***)&opts->xopts);
	for (i = 0; i < opts->xopts_nr; i++) {
		const char *arg = opts->xopts[i];
 
		skip_prefix(arg, "--", &arg);
		opts->xopts[i] = xstrdup(arg);
	}
}
 
static int read_populate_opts(struct replay_opts *opts)
{
	if (is_rebase_i(opts)) {
		struct strbuf buf = STRBUF_INIT;
 
		if (read_oneliner(&buf, rebase_path_gpg_sign_opt(), 1)) {
			if (!starts_with(buf.buf, "-S"))
				strbuf_reset(&buf);
			else {
				free(opts->gpg_sign);
				opts->gpg_sign = xstrdup(buf.buf + 2);
			}
			strbuf_reset(&buf);
		}
 
		if (read_oneliner(&buf, rebase_path_allow_rerere_autoupdate(), 1)) {
			if (!strcmp(buf.buf, "--rerere-autoupdate"))
				opts->allow_rerere_auto = RERERE_AUTOUPDATE;
			else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
				opts->allow_rerere_auto = RERERE_NOAUTOUPDATE;
			strbuf_reset(&buf);
		}
 
		if (file_exists(rebase_path_verbose()))
			opts->verbose = 1;
 
		read_strategy_opts(opts, &buf);
		strbuf_release(&buf);
 
		return 0;
	}
 
	if (!file_exists(git_path_opts_file()))
		return 0;
	/*
	 * The function git_parse_source(), called from git_config_from_file(),
	 * may die() in case of a syntactically incorrect file. We do not care
	 * about this case, though, because we wrote that file ourselves, so we
	 * are pretty certain that it is syntactically correct.
	 */
	if (git_config_from_file(populate_opts_cb, git_path_opts_file(), opts) < 0)
		return error(_("malformed options sheet: '%s'"),
			git_path_opts_file());
	return 0;
}
 
static int walk_revs_populate_todo(struct todo_list *todo_list,
				struct replay_opts *opts)
{
	enum todo_command command = opts->action == REPLAY_PICK ?
		TODO_PICK : TODO_REVERT;
	const char *command_string = todo_command_info[command].str;
	struct commit *commit;
 
	if (prepare_revs(opts))
		return -1;
 
	while ((commit = get_revision(opts->revs))) {
		struct todo_item *item = append_new_todo(todo_list);
		const char *commit_buffer = get_commit_buffer(commit, NULL);
		const char *subject;
		int subject_len;
 
		item->command = command;
		item->commit = commit;
		item->arg = NULL;
		item->arg_len = 0;
		item->offset_in_buf = todo_list->buf.len;
		subject_len = find_commit_subject(commit_buffer, &subject);
		strbuf_addf(&todo_list->buf, "%s %s %.*s\n", command_string,
			short_commit_name(commit), subject_len, subject);
		unuse_commit_buffer(commit, commit_buffer);
	}
	return 0;
}
 
static int create_seq_dir(void)
{
	if (file_exists(git_path_seq_dir())) {
		error(_("a cherry-pick or revert is already in progress"));
		advise(_("try \"git cherry-pick (--continue | --quit | --abort)\""));
		return -1;
	} else if (mkdir(git_path_seq_dir(), 0777) < 0)
		return error_errno(_("could not create sequencer directory '%s'"),
				   git_path_seq_dir());
	return 0;
}
 
static int save_head(const char *head)
{
	static struct lock_file head_lock;
	struct strbuf buf = STRBUF_INIT;
	int fd;
	ssize_t written;
 
	fd = hold_lock_file_for_update(&head_lock, git_path_head_file(), 0);
	if (fd < 0) {
		rollback_lock_file(&head_lock);
		return error_errno(_("could not lock HEAD"));
	}
	strbuf_addf(&buf, "%s\n", head);
	written = write_in_full(fd, buf.buf, buf.len);
	strbuf_release(&buf);
	if (written < 0) {
		rollback_lock_file(&head_lock);
		return error_errno(_("could not write to '%s'"),
				   git_path_head_file());
	}
	if (commit_lock_file(&head_lock) < 0) {
		rollback_lock_file(&head_lock);
		return error(_("failed to finalize '%s'."), git_path_head_file());
	}
	return 0;
}
 
static int rollback_is_safe(void)
{
	struct strbuf sb = STRBUF_INIT;
	struct object_id expected_head, actual_head;
 
	if (strbuf_read_file(&sb, git_path_abort_safety_file(), 0) >= 0) {
		strbuf_trim(&sb);
		if (get_oid_hex(sb.buf, &expected_head)) {
			strbuf_release(&sb);
			die(_("could not parse %s"), git_path_abort_safety_file());
		}
		strbuf_release(&sb);
	}
	else if (errno == ENOENT)
		oidclr(&expected_head);
	else
		die_errno(_("could not read '%s'"), git_path_abort_safety_file());
 
	if (get_oid("HEAD", &actual_head))
		oidclr(&actual_head);
 
	return !oidcmp(&actual_head, &expected_head);
}
 
static int reset_for_rollback(const struct object_id *oid)
{
	const char *argv[4];	/* reset --merge <arg> + NULL */
 
	argv[0] = "reset";
	argv[1] = "--merge";
	argv[2] = oid_to_hex(oid);
	argv[3] = NULL;
	return run_command_v_opt(argv, RUN_GIT_CMD);
}
 
static int rollback_single_pick(void)
{
	struct object_id head_oid;
 
	if (!file_exists(git_path_cherry_pick_head()) &&
	    !file_exists(git_path_revert_head()))
		return error(_("no cherry-pick or revert in progress"));
	if (read_ref_full("HEAD", 0, &head_oid, NULL))
		return error(_("cannot resolve HEAD"));
	if (is_null_oid(&head_oid))
		return error(_("cannot abort from a branch yet to be born"));
	return reset_for_rollback(&head_oid);
}
 
int sequencer_rollback(struct replay_opts *opts)
{
	FILE *f;
	struct object_id oid;
	struct strbuf buf = STRBUF_INIT;
	const char *p;
 
	f = fopen(git_path_head_file(), "r");
	if (!f && errno == ENOENT) {
		/*
		 * There is no multiple-cherry-pick in progress.
		 * If CHERRY_PICK_HEAD or REVERT_HEAD indicates
		 * a single-cherry-pick in progress, abort that.
		 */
		return rollback_single_pick();
	}
	if (!f)
		return error_errno(_("cannot open '%s'"), git_path_head_file());
	if (strbuf_getline_lf(&buf, f)) {
		error(_("cannot read '%s': %s"), git_path_head_file(),
		      ferror(f) ?  strerror(errno) : _("unexpected end of file"));
		fclose(f);
		goto fail;
	}
	fclose(f);
	if (parse_oid_hex(buf.buf, &oid, &p) || *p != '\0') {
		error(_("stored pre-cherry-pick HEAD file '%s' is corrupt"),
			git_path_head_file());
		goto fail;
	}
	if (is_null_oid(&oid)) {
		error(_("cannot abort from a branch yet to be born"));
		goto fail;
	}
 
	if (!rollback_is_safe()) {
		/* Do not error, just do not rollback */
		warning(_("You seem to have moved HEAD. "
			  "Not rewinding, check your HEAD!"));
	} else
	if (reset_for_rollback(&oid))
		goto fail;
	strbuf_release(&buf);
	return sequencer_remove_state(opts);
fail:
	strbuf_release(&buf);
	return -1;
}
 
static int save_todo(struct todo_list *todo_list, struct replay_opts *opts)
{
	static struct lock_file todo_lock;
	const char *todo_path = get_todo_path(opts);
	int next = todo_list->current, offset, fd;
 
	/*
	 * rebase -i writes "git-rebase-todo" without the currently executing
	 * command, appending it to "done" instead.
	 */
	if (is_rebase_i(opts))
		next++;
 
	fd = hold_lock_file_for_update(&todo_lock, todo_path, 0);
	if (fd < 0)
		return error_errno(_("could not lock '%s'"), todo_path);
	offset = next < todo_list->nr ?
		todo_list->items[next].offset_in_buf : todo_list->buf.len;
	if (write_in_full(fd, todo_list->buf.buf + offset,
			todo_list->buf.len - offset) < 0)
		return error_errno(_("could not write to '%s'"), todo_path);
	if (commit_lock_file(&todo_lock) < 0)
		return error(_("failed to finalize '%s'."), todo_path);
 
	if (is_rebase_i(opts)) {
		const char *done_path = rebase_path_done();
		int fd = open(done_path, O_CREAT | O_WRONLY | O_APPEND, 0666);
		int prev_offset = !next ? 0 :
			todo_list->items[next - 1].offset_in_buf;
 
		if (fd >= 0 && offset > prev_offset &&
		    write_in_full(fd, todo_list->buf.buf + prev_offset,
				  offset - prev_offset) < 0) {
			close(fd);
			return error_errno(_("could not write to '%s'"),
					   done_path);
		}
		if (fd >= 0)
			close(fd);
	}
	return 0;
}
 
static int save_opts(struct replay_opts *opts)
{
	const char *opts_file = git_path_opts_file();
	int res = 0;
 
	if (opts->no_commit)
		res |= git_config_set_in_file_gently(opts_file, "options.no-commit", "true");
	if (opts->edit)
		res |= git_config_set_in_file_gently(opts_file, "options.edit", "true");
	if (opts->signoff)
		res |= git_config_set_in_file_gently(opts_file, "options.signoff", "true");
	if (opts->record_origin)
		res |= git_config_set_in_file_gently(opts_file, "options.record-origin", "true");
	if (opts->allow_ff)
		res |= git_config_set_in_file_gently(opts_file, "options.allow-ff", "true");
	if (opts->mainline) {
		struct strbuf buf = STRBUF_INIT;
		strbuf_addf(&buf, "%d", opts->mainline);
		res |= git_config_set_in_file_gently(opts_file, "options.mainline", buf.buf);
		strbuf_release(&buf);
	}
	if (opts->strategy)
		res |= git_config_set_in_file_gently(opts_file, "options.strategy", opts->strategy);
	if (opts->gpg_sign)
		res |= git_config_set_in_file_gently(opts_file, "options.gpg-sign", opts->gpg_sign);
	if (opts->xopts) {
		int i;
		for (i = 0; i < opts->xopts_nr; i++)
			res |= git_config_set_multivar_in_file_gently(opts_file,
							"options.strategy-option",
							opts->xopts[i], "^$", 0);
	}
	if (opts->allow_rerere_auto)
		res |= git_config_set_in_file_gently(opts_file, "options.allow-rerere-auto",
						     opts->allow_rerere_auto == RERERE_AUTOUPDATE ?
						     "true" : "false");
	return res;
}
 
static int make_patch(struct commit *commit, struct replay_opts *opts)
{
	struct strbuf buf = STRBUF_INIT;
	struct rev_info log_tree_opt;
	const char *subject, *p;
	int res = 0;
 
	p = short_commit_name(commit);
	if (write_message(p, strlen(p), rebase_path_stopped_sha(), 1) < 0)
		return -1;
 
	strbuf_addf(&buf, "%s/patch", get_dir(opts));
	memset(&log_tree_opt, 0, sizeof(log_tree_opt));
	init_revisions(&log_tree_opt, NULL);
	log_tree_opt.abbrev = 0;
	log_tree_opt.diff = 1;
	log_tree_opt.diffopt.output_format = DIFF_FORMAT_PATCH;
	log_tree_opt.disable_stdin = 1;
	log_tree_opt.no_commit_id = 1;
	log_tree_opt.diffopt.file = fopen(buf.buf, "w");
	log_tree_opt.diffopt.use_color = GIT_COLOR_NEVER;
	if (!log_tree_opt.diffopt.file)
		res |= error_errno(_("could not open '%s'"), buf.buf);
	else {
		res |= log_tree_commit(&log_tree_opt, commit);
		fclose(log_tree_opt.diffopt.file);
	}
	strbuf_reset(&buf);
 
	strbuf_addf(&buf, "%s/message", get_dir(opts));
	if (!file_exists(buf.buf)) {
		const char *commit_buffer = get_commit_buffer(commit, NULL);
		find_commit_subject(commit_buffer, &subject);
		res |= write_message(subject, strlen(subject), buf.buf, 1);
		unuse_commit_buffer(commit, commit_buffer);
	}
	strbuf_release(&buf);
 
	return res;
}
 
static int intend_to_amend(void)
{
	struct object_id head;
	char *p;
 
	if (get_oid("HEAD", &head))
		return error(_("cannot read HEAD"));
 
	p = oid_to_hex(&head);
	return write_message(p, strlen(p), rebase_path_amend(), 1);
}
 
static int error_with_patch(struct commit *commit,
	const char *subject, int subject_len,
	struct replay_opts *opts, int exit_code, int to_amend)
{
	if (make_patch(commit, opts))
		return -1;
 
	if (to_amend) {
		if (intend_to_amend())
			return -1;
 
		fprintf(stderr, "You can amend the commit now, with\n"
			"\n"
			"  git commit --amend %s\n"
			"\n"
			"Once you are satisfied with your changes, run\n"
			"\n"
			"  git rebase --continue\n", gpg_sign_opt_quoted(opts));
	} else if (exit_code)
		fprintf(stderr, "Could not apply %s... %.*s\n",
			short_commit_name(commit), subject_len, subject);
 
	return exit_code;
}
 
static int error_failed_squash(struct commit *commit,
	struct replay_opts *opts, int subject_len, const char *subject)
{
	if (rename(rebase_path_squash_msg(), rebase_path_message()))
		return error(_("could not rename '%s' to '%s'"),
			rebase_path_squash_msg(), rebase_path_message());
	unlink(rebase_path_fixup_msg());
	unlink(git_path_merge_msg());
	if (copy_file(git_path_merge_msg(), rebase_path_message(), 0666))
		return error(_("could not copy '%s' to '%s'"),
			     rebase_path_message(), git_path_merge_msg());
	return error_with_patch(commit, subject, subject_len, opts, 1, 0);
}
 
static int do_exec(const char *command_line)
{
	const char *child_argv[] = { NULL, NULL };
	int dirty, status;
 
	fprintf(stderr, "Executing: %s\n", command_line);
	child_argv[0] = command_line;
	status = run_command_v_opt(child_argv, RUN_USING_SHELL);
 
	/* force re-reading of the cache */
	if (discard_cache() < 0 || read_cache() < 0)
		return error(_("could not read index"));
 
	dirty = require_clean_work_tree("rebase", NULL, 1, 1);
 
	if (status) {
		warning(_("execution failed: %s\n%s"
			  "You can fix the problem, and then run\n"
			  "\n"
			  "  git rebase --continue\n"
			  "\n"),
			command_line,
			dirty ? N_("and made changes to the index and/or the "
				"working tree\n") : "");
		if (status == 127)
			/* command not found */
			status = 1;
	} else if (dirty) {
		warning(_("execution succeeded: %s\nbut "
			  "left changes to the index and/or the working tree\n"
			  "Commit or stash your changes, and then run\n"
			  "\n"
			  "  git rebase --continue\n"
			  "\n"), command_line);
		status = 1;
	}
 
	return status;
}
 
static int is_final_fixup(struct todo_list *todo_list)
{
	int i = todo_list->current;
 
	if (!is_fixup(todo_list->items[i].command))
		return 0;
 
	while (++i < todo_list->nr)
		if (is_fixup(todo_list->items[i].command))
			return 0;
		else if (!is_noop(todo_list->items[i].command))
			break;
	return 1;
}
 
static enum todo_command peek_command(struct todo_list *todo_list, int offset)
{
	int i;
 
	for (i = todo_list->current + offset; i < todo_list->nr; i++)
		if (!is_noop(todo_list->items[i].command))
			return todo_list->items[i].command;
 
	return -1;
}
 
static int apply_autostash(struct replay_opts *opts)
{
	struct strbuf stash_sha1 = STRBUF_INIT;
	struct child_process child = CHILD_PROCESS_INIT;
	int ret = 0;
 
	if (!read_oneliner(&stash_sha1, rebase_path_autostash(), 1)) {
		strbuf_release(&stash_sha1);
		return 0;
	}
	strbuf_trim(&stash_sha1);
 
	child.git_cmd = 1;
	child.no_stdout = 1;
	child.no_stderr = 1;
	argv_array_push(&child.args, "stash");
	argv_array_push(&child.args, "apply");
	argv_array_push(&child.args, stash_sha1.buf);
	if (!run_command(&child))
		fprintf(stderr, _("Applied autostash.\n"));
	else {
		struct child_process store = CHILD_PROCESS_INIT;
 
		store.git_cmd = 1;
		argv_array_push(&store.args, "stash");
		argv_array_push(&store.args, "store");
		argv_array_push(&store.args, "-m");
		argv_array_push(&store.args, "autostash");
		argv_array_push(&store.args, "-q");
		argv_array_push(&store.args, stash_sha1.buf);
		if (run_command(&store))
			ret = error(_("cannot store %s"), stash_sha1.buf);
		else
			fprintf(stderr,
				_("Applying autostash resulted in conflicts.\n"
				  "Your changes are safe in the stash.\n"
				  "You can run \"git stash pop\" or"
				  " \"git stash drop\" at any time.\n"));
	}
 
	strbuf_release(&stash_sha1);
	return ret;
}
 
static const char *reflog_message(struct replay_opts *opts,
	const char *sub_action, const char *fmt, ...)
{
	va_list ap;
	static struct strbuf buf = STRBUF_INIT;
 
	va_start(ap, fmt);
	strbuf_reset(&buf);
	strbuf_addstr(&buf, action_name(opts));
	if (sub_action)
		strbuf_addf(&buf, " (%s)", sub_action);
	if (fmt) {
		strbuf_addstr(&buf, ": ");
		strbuf_vaddf(&buf, fmt, ap);
	}
	va_end(ap);
 
	return buf.buf;
}
 
static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
{
	int res = 0;
 
	setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
	if (opts->allow_ff)
		assert(!(opts->signoff || opts->no_commit ||
				opts->record_origin || opts->edit));
	if (read_and_refresh_cache(opts))
		return -1;
 
	while (todo_list->current < todo_list->nr) {
		struct todo_item *item = todo_list->items + todo_list->current;
		if (save_todo(todo_list, opts))
			return -1;
		if (is_rebase_i(opts)) {
			if (item->command != TODO_COMMENT) {
				FILE *f = fopen(rebase_path_msgnum(), "w");
 
				todo_list->done_nr++;
 
				if (f) {
					fprintf(f, "%d\n", todo_list->done_nr);
					fclose(f);
				}
				fprintf(stderr, "Rebasing (%d/%d)%s",
					todo_list->done_nr,
					todo_list->total_nr,
					opts->verbose ? "\n" : "\r");
			}
			unlink(rebase_path_message());
			unlink(rebase_path_author_script());
			unlink(rebase_path_stopped_sha());
			unlink(rebase_path_amend());
		}
		if (item->command <= TODO_SQUASH) {
			if (is_rebase_i(opts))
				setenv("GIT_REFLOG_ACTION", reflog_message(opts,
					command_to_string(item->command), NULL),
					1);
			res = do_pick_commit(item->command, item->commit,
					opts, is_final_fixup(todo_list));
			if (is_rebase_i(opts) && res < 0) {
				/* Reschedule */
				todo_list->current--;
				if (save_todo(todo_list, opts))
					return -1;
			}
			if (item->command == TODO_EDIT) {
				struct commit *commit = item->commit;
				if (!res)
					fprintf(stderr,
						_("Stopped at %s...  %.*s\n"),
						short_commit_name(commit),
						item->arg_len, item->arg);
				return error_with_patch(commit,
					item->arg, item->arg_len, opts, res,
					!res);
			}
			if (is_rebase_i(opts) && !res)
				record_in_rewritten(&item->commit->object.oid,
					peek_command(todo_list, 1));
			if (res && is_fixup(item->command)) {
				if (res == 1)
					intend_to_amend();
				return error_failed_squash(item->commit, opts,
					item->arg_len, item->arg);
			} else if (res && is_rebase_i(opts))
				return res | error_with_patch(item->commit,
					item->arg, item->arg_len, opts, res,
					item->command == TODO_REWORD);
		} else if (item->command == TODO_EXEC) {
			char *end_of_arg = (char *)(item->arg + item->arg_len);
			int saved = *end_of_arg;
			struct stat st;
 
			*end_of_arg = '\0';
			res = do_exec(item->arg);
			*end_of_arg = saved;
 
			/* Reread the todo file if it has changed. */
			if (res)
				; /* fall through */
			else if (stat(get_todo_path(opts), &st))
				res = error_errno(_("could not stat '%s'"),
						  get_todo_path(opts));
			else if (match_stat_data(&todo_list->stat, &st)) {
				todo_list_release(todo_list);
				if (read_populate_todo(todo_list, opts))
					res = -1; /* message was printed */
				/* `current` will be incremented below */
				todo_list->current = -1;
			}
		} else if (!is_noop(item->command))
			return error(_("unknown command %d"), item->command);
 
		todo_list->current++;
		if (res)
			return res;
	}
 
	if (is_rebase_i(opts)) {
		struct strbuf head_ref = STRBUF_INIT, buf = STRBUF_INIT;
		struct stat st;
 
		/* Stopped in the middle, as planned? */
		if (todo_list->current < todo_list->nr)
			return 0;
 
		if (read_oneliner(&head_ref, rebase_path_head_name(), 0) &&
				starts_with(head_ref.buf, "refs/")) {
			const char *msg;
			struct object_id head, orig;
			int res;
 
			if (get_oid("HEAD", &head)) {
				res = error(_("cannot read HEAD"));
cleanup_head_ref:
				strbuf_release(&head_ref);
				strbuf_release(&buf);
				return res;
			}
			if (!read_oneliner(&buf, rebase_path_orig_head(), 0) ||
					get_oid_hex(buf.buf, &orig)) {
				res = error(_("could not read orig-head"));
				goto cleanup_head_ref;
			}
			strbuf_reset(&buf);
			if (!read_oneliner(&buf, rebase_path_onto(), 0)) {
				res = error(_("could not read 'onto'"));
				goto cleanup_head_ref;
			}
			msg = reflog_message(opts, "finish", "%s onto %s",
				head_ref.buf, buf.buf);
			if (update_ref(msg, head_ref.buf, &head, &orig,
				       REF_NODEREF, UPDATE_REFS_MSG_ON_ERR)) {
				res = error(_("could not update %s"),
					head_ref.buf);
				goto cleanup_head_ref;
			}
			msg = reflog_message(opts, "finish", "returning to %s",
				head_ref.buf);
			if (create_symref("HEAD", head_ref.buf, msg)) {
				res = error(_("could not update HEAD to %s"),
					head_ref.buf);
				goto cleanup_head_ref;
			}
			strbuf_reset(&buf);
		}
 
		if (opts->verbose) {
			struct rev_info log_tree_opt;
			struct object_id orig, head;
 
			memset(&log_tree_opt, 0, sizeof(log_tree_opt));
			init_revisions(&log_tree_opt, NULL);
			log_tree_opt.diff = 1;
			log_tree_opt.diffopt.output_format =
				DIFF_FORMAT_DIFFSTAT;
			log_tree_opt.disable_stdin = 1;
 
			if (read_oneliner(&buf, rebase_path_orig_head(), 0) &&
			    !get_oid(buf.buf, &orig) &&
			    !get_oid("HEAD", &head)) {
				diff_tree_oid(&orig, &head, "",
					      &log_tree_opt.diffopt);
				log_tree_diff_flush(&log_tree_opt);
			}
		}
		flush_rewritten_pending();
		if (!stat(rebase_path_rewritten_list(), &st) &&
				st.st_size > 0) {
			struct child_process child = CHILD_PROCESS_INIT;
			const char *post_rewrite_hook =
				find_hook("post-rewrite");
 
			child.in = open(rebase_path_rewritten_list(), O_RDONLY);
			child.git_cmd = 1;
			argv_array_push(&child.args, "notes");
			argv_array_push(&child.args, "copy");
			argv_array_push(&child.args, "--for-rewrite=rebase");
			/* we don't care if this copying failed */
			run_command(&child);
 
			if (post_rewrite_hook) {
				struct child_process hook = CHILD_PROCESS_INIT;
 
				hook.in = open(rebase_path_rewritten_list(),
					O_RDONLY);
				hook.stdout_to_stderr = 1;
				argv_array_push(&hook.args, post_rewrite_hook);
				argv_array_push(&hook.args, "rebase");
				/* we don't care if this hook failed */
				run_command(&hook);
			}
		}
		apply_autostash(opts);
 
		fprintf(stderr, "Successfully rebased and updated %s.\n",
			head_ref.buf);
 
		strbuf_release(&buf);
		strbuf_release(&head_ref);
	}
 
	/*
	 * Sequence of picks finished successfully; cleanup by
	 * removing the .git/sequencer directory
	 */
	return sequencer_remove_state(opts);
}
 
static int continue_single_pick(void)
{
	const char *argv[] = { "commit", NULL };
 
	if (!file_exists(git_path_cherry_pick_head()) &&
	    !file_exists(git_path_revert_head()))
		return error(_("no cherry-pick or revert in progress"));
	return run_command_v_opt(argv, RUN_GIT_CMD);
}
 
static int commit_staged_changes(struct replay_opts *opts)
{
	unsigned int flags = ALLOW_EMPTY | EDIT_MSG;
 
	if (has_unstaged_changes(1))
		return error(_("cannot rebase: You have unstaged changes."));
	if (!has_uncommitted_changes(0)) {
		const char *cherry_pick_head = git_path_cherry_pick_head();
 
		if (file_exists(cherry_pick_head) && unlink(cherry_pick_head))
			return error(_("could not remove CHERRY_PICK_HEAD"));
		return 0;
	}
 
	if (file_exists(rebase_path_amend())) {
		struct strbuf rev = STRBUF_INIT;
		struct object_id head, to_amend;
 
		if (get_oid("HEAD", &head))
			return error(_("cannot amend non-existing commit"));
		if (!read_oneliner(&rev, rebase_path_amend(), 0))
			return error(_("invalid file: '%s'"), rebase_path_amend());
		if (get_oid_hex(rev.buf, &to_amend))
			return error(_("invalid contents: '%s'"),
				rebase_path_amend());
		if (oidcmp(&head, &to_amend))
			return error(_("\nYou have uncommitted changes in your "
				       "working tree. Please, commit them\n"
				       "first and then run 'git rebase "
				       "--continue' again."));
 
		strbuf_release(&rev);
		flags |= AMEND_MSG;
	}
 
	if (run_git_commit(rebase_path_message(), opts, flags))
		return error(_("could not commit staged changes."));
	unlink(rebase_path_amend());
	return 0;
}
 
int sequencer_continue(struct replay_opts *opts)
{
	struct todo_list todo_list = TODO_LIST_INIT;
	int res;
 
	if (read_and_refresh_cache(opts))
		return -1;
 
	if (is_rebase_i(opts)) {
		if (commit_staged_changes(opts))
			return -1;
	} else if (!file_exists(get_todo_path(opts)))
		return continue_single_pick();
	if (read_populate_opts(opts))
		return -1;
	if ((res = read_populate_todo(&todo_list, opts)))
		goto release_todo_list;
 
	if (!is_rebase_i(opts)) {
		/* Verify that the conflict has been resolved */
		if (file_exists(git_path_cherry_pick_head()) ||
		    file_exists(git_path_revert_head())) {
			res = continue_single_pick();
			if (res)
				goto release_todo_list;
		}
		if (index_differs_from("HEAD", 0, 0)) {
			res = error_dirty_index(opts);
			goto release_todo_list;
		}
		todo_list.current++;
	} else if (file_exists(rebase_path_stopped_sha())) {
		struct strbuf buf = STRBUF_INIT;
		struct object_id oid;
 
		if (read_oneliner(&buf, rebase_path_stopped_sha(), 1) &&
		    !get_oid_committish(buf.buf, &oid))
			record_in_rewritten(&oid, peek_command(&todo_list, 0));
		strbuf_release(&buf);
	}
 
	res = pick_commits(&todo_list, opts);
release_todo_list:
	todo_list_release(&todo_list);
	return res;
}
 
static int single_pick(struct commit *cmit, struct replay_opts *opts)
{
	setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
	return do_pick_commit(opts->action == REPLAY_PICK ?
		TODO_PICK : TODO_REVERT, cmit, opts, 0);
}
 
int sequencer_pick_revisions(struct replay_opts *opts)
{
	struct todo_list todo_list = TODO_LIST_INIT;
	struct object_id oid;
	int i, res;
 
	assert(opts->revs);
	if (read_and_refresh_cache(opts))
		return -1;
 
	for (i = 0; i < opts->revs->pending.nr; i++) {
		struct object_id oid;
		const char *name = opts->revs->pending.objects[i].name;
 
		/* This happens when using --stdin. */
		if (!strlen(name))
			continue;
 
		if (!get_oid(name, &oid)) {
			if (!lookup_commit_reference_gently(&oid, 1)) {
				enum object_type type = sha1_object_info(oid.hash, NULL);
				return error(_("%s: can't cherry-pick a %s"),
					name, typename(type));
			}
		} else
			return error(_("%s: bad revision"), name);
	}
 
	/*
	 * If we were called as "git cherry-pick <commit>", just
	 * cherry-pick/revert it, set CHERRY_PICK_HEAD /
	 * REVERT_HEAD, and don't touch the sequencer state.
	 * This means it is possible to cherry-pick in the middle
	 * of a cherry-pick sequence.
	 */
	if (opts->revs->cmdline.nr == 1 &&
	    opts->revs->cmdline.rev->whence == REV_CMD_REV &&
	    opts->revs->no_walk &&
	    !opts->revs->cmdline.rev->flags) {
		struct commit *cmit;
		if (prepare_revision_walk(opts->revs))
			return error(_("revision walk setup failed"));
		cmit = get_revision(opts->revs);
		if (!cmit || get_revision(opts->revs))
			return error("BUG: expected exactly one commit from walk");
		return single_pick(cmit, opts);
	}
 
	/*
	 * Start a new cherry-pick/ revert sequence; but
	 * first, make sure that an existing one isn't in
	 * progress
	 */
 
	if (walk_revs_populate_todo(&todo_list, opts) ||
			create_seq_dir() < 0)
		return -1;
	if (get_oid("HEAD", &oid) && (opts->action == REPLAY_REVERT))
		return error(_("can't revert as initial commit"));
	if (save_head(oid_to_hex(&oid)))
		return -1;
	if (save_opts(opts))
		return -1;
	update_abort_safety_file();
	res = pick_commits(&todo_list, opts);
	todo_list_release(&todo_list);
	return res;
}
 
void append_signoff(struct strbuf *msgbuf, int ignore_footer, unsigned flag)
{
	unsigned no_dup_sob = flag & APPEND_SIGNOFF_DEDUP;
	struct strbuf sob = STRBUF_INIT;
	int has_footer;
 
	strbuf_addstr(&sob, sign_off_header);
	strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
				getenv("GIT_COMMITTER_EMAIL")));
	strbuf_addch(&sob, '\n');
 
	if (!ignore_footer)
		strbuf_complete_line(msgbuf);
 
	/*
	 * If the whole message buffer is equal to the sob, pretend that we
	 * found a conforming footer with a matching sob
	 */
	if (msgbuf->len - ignore_footer == sob.len &&
	    !strncmp(msgbuf->buf, sob.buf, sob.len))
		has_footer = 3;
	else
		has_footer = has_conforming_footer(msgbuf, &sob, ignore_footer);
 
	if (!has_footer) {
		const char *append_newlines = NULL;
		size_t len = msgbuf->len - ignore_footer;
 
		if (!len) {
			/*
			 * The buffer is completely empty.  Leave foom for
			 * the title and body to be filled in by the user.
			 */
			append_newlines = "\n\n";
		} else if (len == 1) {
			/*
			 * Buffer contains a single newline.  Add another
			 * so that we leave room for the title and body.
			 */
			append_newlines = "\n";
		} else if (msgbuf->buf[len - 2] != '\n') {
			/*
			 * Buffer ends with a single newline.  Add another
			 * so that there is an empty line between the message
			 * body and the sob.
			 */
			append_newlines = "\n";
		} /* else, the buffer already ends with two newlines. */
 
		if (append_newlines)
			strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
				append_newlines, strlen(append_newlines));
	}
 
	if (has_footer != 3 && (!no_dup_sob || has_footer != 2))
		strbuf_splice(msgbuf, msgbuf->len - ignore_footer, 0,
				sob.buf, sob.len);
 
	strbuf_release(&sob);
}
 
int sequencer_make_script(int keep_empty, FILE *out,
		int argc, const char **argv)
{
	char *format = NULL;
	struct pretty_print_context pp = {0};
	struct strbuf buf = STRBUF_INIT;
	struct rev_info revs;
	struct commit *commit;
 
	init_revisions(&revs, NULL);
	revs.verbose_header = 1;
	revs.max_parents = 1;
	revs.cherry_pick = 1;
	revs.limited = 1;
	revs.reverse = 1;
	revs.right_only = 1;
	revs.sort_order = REV_SORT_IN_GRAPH_ORDER;
	revs.topo_order = 1;
 
	revs.pretty_given = 1;
	git_config_get_string("rebase.instructionFormat", &format);
	if (!format || !*format) {
		free(format);
		format = xstrdup("%s");
	}
	get_commit_format(format, &revs);
	free(format);
	pp.fmt = revs.commit_format;
	pp.output_encoding = get_log_output_encoding();
 
	if (setup_revisions(argc, argv, &revs, NULL) > 1)
		return error(_("make_script: unhandled options"));
 
	if (prepare_revision_walk(&revs) < 0)
		return error(_("make_script: error preparing revisions"));
 
	while ((commit = get_revision(&revs))) {
		strbuf_reset(&buf);
		if (!keep_empty && is_original_commit_empty(commit))
			strbuf_addf(&buf, "%c ", comment_line_char);
		strbuf_addf(&buf, "pick %s ", oid_to_hex(&commit->object.oid));
		pretty_print_commit(&pp, commit, &buf);
		strbuf_addch(&buf, '\n');
		fputs(buf.buf, out);
	}
	strbuf_release(&buf);
	return 0;
}
 
 
int transform_todo_ids(int shorten_ids)
{
	const char *todo_file = rebase_path_todo();
	struct todo_list todo_list = TODO_LIST_INIT;
	int fd, res, i;
	FILE *out;
 
	strbuf_reset(&todo_list.buf);
	fd = open(todo_file, O_RDONLY);
	if (fd < 0)
		return error_errno(_("could not open '%s'"), todo_file);
	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
		close(fd);
		return error(_("could not read '%s'."), todo_file);
	}
	close(fd);
 
	res = parse_insn_buffer(todo_list.buf.buf, &todo_list);
	if (res) {
		todo_list_release(&todo_list);
		return error(_("unusable todo list: '%s'"), todo_file);
	}
 
	out = fopen(todo_file, "w");
	if (!out) {
		todo_list_release(&todo_list);
		return error(_("unable to open '%s' for writing"), todo_file);
	}
	for (i = 0; i < todo_list.nr; i++) {
		struct todo_item *item = todo_list.items + i;
		int bol = item->offset_in_buf;
		const char *p = todo_list.buf.buf + bol;
		int eol = i + 1 < todo_list.nr ?
			todo_list.items[i + 1].offset_in_buf :
			todo_list.buf.len;
 
		if (item->command >= TODO_EXEC && item->command != TODO_DROP)
			fwrite(p, eol - bol, 1, out);
		else {
			const char *id = shorten_ids ?
				short_commit_name(item->commit) :
				oid_to_hex(&item->commit->object.oid);
			int len;
 
			p += strspn(p, " \t"); /* left-trim command */
			len = strcspn(p, " \t"); /* length of command */
 
			fprintf(out, "%.*s %s %.*s\n",
				len, p, id, item->arg_len, item->arg);
		}
	}
	fclose(out);
	todo_list_release(&todo_list);
	return 0;
}
 
enum check_level {
	CHECK_IGNORE = 0, CHECK_WARN, CHECK_ERROR
};
 
static enum check_level get_missing_commit_check_level(void)
{
	const char *value;
 
	if (git_config_get_value("rebase.missingcommitscheck", &value) ||
			!strcasecmp("ignore", value))
		return CHECK_IGNORE;
	if (!strcasecmp("warn", value))
		return CHECK_WARN;
	if (!strcasecmp("error", value))
		return CHECK_ERROR;
	warning(_("unrecognized setting %s for option "
		  "rebase.missingCommitsCheck. Ignoring."), value);
	return CHECK_IGNORE;
}
 
/*
 * Check if the user dropped some commits by mistake
 * Behaviour determined by rebase.missingCommitsCheck.
 * Check if there is an unrecognized command or a
 * bad SHA-1 in a command.
 */
int check_todo_list(void)
{
	enum check_level check_level = get_missing_commit_check_level();
	struct strbuf todo_file = STRBUF_INIT;
	struct todo_list todo_list = TODO_LIST_INIT;
	struct strbuf missing = STRBUF_INIT;
	int advise_to_edit_todo = 0, res = 0, fd, i;
 
	strbuf_addstr(&todo_file, rebase_path_todo());
	fd = open(todo_file.buf, O_RDONLY);
	if (fd < 0) {
		res = error_errno(_("could not open '%s'"), todo_file.buf);
		goto leave_check;
	}
	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
		close(fd);
		res = error(_("could not read '%s'."), todo_file.buf);
		goto leave_check;
	}
	close(fd);
	advise_to_edit_todo = res =
		parse_insn_buffer(todo_list.buf.buf, &todo_list);
 
	if (res || check_level == CHECK_IGNORE)
		goto leave_check;
 
	/* Mark the commits in git-rebase-todo as seen */
	for (i = 0; i < todo_list.nr; i++) {
		struct commit *commit = todo_list.items[i].commit;
		if (commit)
			commit->util = (void *)1;
	}
 
	todo_list_release(&todo_list);
	strbuf_addstr(&todo_file, ".backup");
	fd = open(todo_file.buf, O_RDONLY);
	if (fd < 0) {
		res = error_errno(_("could not open '%s'"), todo_file.buf);
		goto leave_check;
	}
	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
		close(fd);
		res = error(_("could not read '%s'."), todo_file.buf);
		goto leave_check;
	}
	close(fd);
	strbuf_release(&todo_file);
	res = !!parse_insn_buffer(todo_list.buf.buf, &todo_list);
 
	/* Find commits in git-rebase-todo.backup yet unseen */
	for (i = todo_list.nr - 1; i >= 0; i--) {
		struct todo_item *item = todo_list.items + i;
		struct commit *commit = item->commit;
		if (commit && !commit->util) {
			strbuf_addf(&missing, " - %s %.*s\n",
				    short_commit_name(commit),
				    item->arg_len, item->arg);
			commit->util = (void *)1;
		}
	}
 
	/* Warn about missing commits */
	if (!missing.len)
		goto leave_check;
 
	if (check_level == CHECK_ERROR)
		advise_to_edit_todo = res = 1;
 
	fprintf(stderr,
		_("Warning: some commits may have been dropped accidentally.\n"
		"Dropped commits (newer to older):\n"));
 
	/* Make the list user-friendly and display */
	fputs(missing.buf, stderr);
	strbuf_release(&missing);
 
	fprintf(stderr, _("To avoid this message, use \"drop\" to "
		"explicitly remove a commit.\n\n"
		"Use 'git config rebase.missingCommitsCheck' to change "
		"the level of warnings.\n"
		"The possible behaviours are: ignore, warn, error.\n\n"));
 
leave_check:
	strbuf_release(&todo_file);
	todo_list_release(&todo_list);
 
	if (advise_to_edit_todo)
		fprintf(stderr,
			_("You can fix this with 'git rebase --edit-todo' "
			  "and then run 'git rebase --continue'.\n"
			  "Or you can abort the rebase with 'git rebase"
			  " --abort'.\n"));
 
	return res;
}
 
/* skip picking commits whose parents are unchanged */
int skip_unnecessary_picks(void)
{
	const char *todo_file = rebase_path_todo();
	struct strbuf buf = STRBUF_INIT;
	struct todo_list todo_list = TODO_LIST_INIT;
	struct object_id onto_oid, *oid = &onto_oid, *parent_oid;
	int fd, i;
 
	if (!read_oneliner(&buf, rebase_path_onto(), 0))
		return error(_("could not read 'onto'"));
	if (get_oid(buf.buf, &onto_oid)) {
		strbuf_release(&buf);
		return error(_("need a HEAD to fixup"));
	}
	strbuf_release(&buf);
 
	fd = open(todo_file, O_RDONLY);
	if (fd < 0) {
		return error_errno(_("could not open '%s'"), todo_file);
	}
	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
		close(fd);
		return error(_("could not read '%s'."), todo_file);
	}
	close(fd);
	if (parse_insn_buffer(todo_list.buf.buf, &todo_list) < 0) {
		todo_list_release(&todo_list);
		return -1;
	}
 
	for (i = 0; i < todo_list.nr; i++) {
		struct todo_item *item = todo_list.items + i;
 
		if (item->command >= TODO_NOOP)
			continue;
		if (item->command != TODO_PICK)
			break;
		if (parse_commit(item->commit)) {
			todo_list_release(&todo_list);
			return error(_("could not parse commit '%s'"),
				oid_to_hex(&item->commit->object.oid));
		}
		if (!item->commit->parents)
			break; /* root commit */
		if (item->commit->parents->next)
			break; /* merge commit */
		parent_oid = &item->commit->parents->item->object.oid;
		if (hashcmp(parent_oid->hash, oid->hash))
			break;
		oid = &item->commit->object.oid;
	}
	if (i > 0) {
		int offset = i < todo_list.nr ?
			todo_list.items[i].offset_in_buf : todo_list.buf.len;
		const char *done_path = rebase_path_done();
 
		fd = open(done_path, O_CREAT | O_WRONLY | O_APPEND, 0666);
		if (fd < 0) {
			error_errno(_("could not open '%s' for writing"),
				    done_path);
			todo_list_release(&todo_list);
			return -1;
		}
		if (write_in_full(fd, todo_list.buf.buf, offset) < 0) {
			error_errno(_("could not write to '%s'"), done_path);
			todo_list_release(&todo_list);
			close(fd);
			return -1;
		}
		close(fd);
 
		fd = open(rebase_path_todo(), O_WRONLY, 0666);
		if (fd < 0) {
			error_errno(_("could not open '%s' for writing"),
				    rebase_path_todo());
			todo_list_release(&todo_list);
			return -1;
		}
		if (write_in_full(fd, todo_list.buf.buf + offset,
				todo_list.buf.len - offset) < 0) {
			error_errno(_("could not write to '%s'"),
				    rebase_path_todo());
			close(fd);
			todo_list_release(&todo_list);
			return -1;
		}
		if (ftruncate(fd, todo_list.buf.len - offset) < 0) {
			error_errno(_("could not truncate '%s'"),
				    rebase_path_todo());
			todo_list_release(&todo_list);
			close(fd);
			return -1;
		}
		close(fd);
 
		todo_list.current = i;
		if (is_fixup(peek_command(&todo_list, 0)))
			record_in_rewritten(oid, peek_command(&todo_list, 0));
	}
 
	todo_list_release(&todo_list);
	printf("%s\n", oid_to_hex(oid));
 
	return 0;
}
 
struct subject2item_entry {
	struct hashmap_entry entry;
	int i;
	char subject[FLEX_ARRAY];
};
 
static int subject2item_cmp(const void *fndata,
			    const struct subject2item_entry *a,
			    const struct subject2item_entry *b, const void *key)
{
	return key ? strcmp(a->subject, key) : strcmp(a->subject, b->subject);
}
 
/*
 * Rearrange the todo list that has both "pick commit-id msg" and "pick
 * commit-id fixup!/squash! msg" in it so that the latter is put immediately
 * after the former, and change "pick" to "fixup"/"squash".
 *
 * Note that if the config has specified a custom instruction format, each log
 * message will have to be retrieved from the commit (as the oneline in the
 * script cannot be trusted) in order to normalize the autosquash arrangement.
 */
int rearrange_squash(void)
{
	const char *todo_file = rebase_path_todo();
	struct todo_list todo_list = TODO_LIST_INIT;
	struct hashmap subject2item;
	int res = 0, rearranged = 0, *next, *tail, fd, i;
	char **subjects;
 
	fd = open(todo_file, O_RDONLY);
	if (fd < 0)
		return error_errno(_("could not open '%s'"), todo_file);
	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
		close(fd);
		return error(_("could not read '%s'."), todo_file);
	}
	close(fd);
	if (parse_insn_buffer(todo_list.buf.buf, &todo_list) < 0) {
		todo_list_release(&todo_list);
		return -1;
	}
 
	/*
	 * The hashmap maps onelines to the respective todo list index.
	 *
	 * If any items need to be rearranged, the next[i] value will indicate
	 * which item was moved directly after the i'th.
	 *
	 * In that case, last[i] will indicate the index of the latest item to
	 * be moved to appear after the i'th.
	 */
	hashmap_init(&subject2item, (hashmap_cmp_fn) subject2item_cmp,
		     NULL, todo_list.nr);
	ALLOC_ARRAY(next, todo_list.nr);
	ALLOC_ARRAY(tail, todo_list.nr);
	ALLOC_ARRAY(subjects, todo_list.nr);
	for (i = 0; i < todo_list.nr; i++) {
		struct strbuf buf = STRBUF_INIT;
		struct todo_item *item = todo_list.items + i;
		const char *commit_buffer, *subject, *p;
		size_t subject_len;
		int i2 = -1;
		struct subject2item_entry *entry;
 
		next[i] = tail[i] = -1;
		if (item->command >= TODO_EXEC) {
			subjects[i] = NULL;
			continue;
		}
 
		if (is_fixup(item->command)) {
			todo_list_release(&todo_list);
			return error(_("the script was already rearranged."));
		}
 
		item->commit->util = item;
 
		parse_commit(item->commit);
		commit_buffer = get_commit_buffer(item->commit, NULL);
		find_commit_subject(commit_buffer, &subject);
		format_subject(&buf, subject, " ");
		subject = subjects[i] = strbuf_detach(&buf, &subject_len);
		unuse_commit_buffer(item->commit, commit_buffer);
		if ((skip_prefix(subject, "fixup! ", &p) ||
		     skip_prefix(subject, "squash! ", &p))) {
			struct commit *commit2;
 
			for (;;) {
				while (isspace(*p))
					p++;
				if (!skip_prefix(p, "fixup! ", &p) &&
				    !skip_prefix(p, "squash! ", &p))
					break;
			}
 
			if ((entry = hashmap_get_from_hash(&subject2item,
							   strhash(p), p)))
				/* found by title */
				i2 = entry->i;
			else if (!strchr(p, ' ') &&
				 (commit2 =
				  lookup_commit_reference_by_name(p)) &&
				 commit2->util)
				/* found by commit name */
				i2 = (struct todo_item *)commit2->util
					- todo_list.items;
			else {
				/* copy can be a prefix of the commit subject */
				for (i2 = 0; i2 < i; i2++)
					if (subjects[i2] &&
					    starts_with(subjects[i2], p))
						break;
				if (i2 == i)
					i2 = -1;
			}
		}
		if (i2 >= 0) {
			rearranged = 1;
			todo_list.items[i].command =
				starts_with(subject, "fixup!") ?
				TODO_FIXUP : TODO_SQUASH;
			if (next[i2] < 0)
				next[i2] = i;
			else
				next[tail[i2]] = i;
			tail[i2] = i;
		} else if (!hashmap_get_from_hash(&subject2item,
						strhash(subject), subject)) {
			FLEX_ALLOC_MEM(entry, subject, subject, subject_len);
			entry->i = i;
			hashmap_entry_init(entry, strhash(entry->subject));
			hashmap_put(&subject2item, entry);
		}
	}
 
	if (rearranged) {
		struct strbuf buf = STRBUF_INIT;
 
		for (i = 0; i < todo_list.nr; i++) {
			enum todo_command command = todo_list.items[i].command;
			int cur = i;
 
			/*
			 * Initially, all commands are 'pick's. If it is a
			 * fixup or a squash now, we have rearranged it.
			 */
			if (is_fixup(command))
				continue;
 
			while (cur >= 0) {
				int offset = todo_list.items[cur].offset_in_buf;
				int end_offset = cur + 1 < todo_list.nr ?
					todo_list.items[cur + 1].offset_in_buf :
					todo_list.buf.len;
				char *bol = todo_list.buf.buf + offset;
				char *eol = todo_list.buf.buf + end_offset;
 
				/* replace 'pick', by 'fixup' or 'squash' */
				command = todo_list.items[cur].command;
				if (is_fixup(command)) {
					strbuf_addstr(&buf,
						todo_command_info[command].str);
					bol += strcspn(bol, " \t");
				}
 
				strbuf_add(&buf, bol, eol - bol);
 
				cur = next[cur];
			}
		}
 
		fd = open(todo_file, O_WRONLY);
		if (fd < 0)
			res = error_errno(_("could not open '%s'"), todo_file);
		else if (write(fd, buf.buf, buf.len) < 0)
			res = error_errno(_("could not read '%s'."), todo_file);
		else if (ftruncate(fd, buf.len) < 0)
			res = error_errno(_("could not finish '%s'"),
					   todo_file);
		close(fd);
		strbuf_release(&buf);
	}
 
	free(next);
	free(tail);
	for (i = 0; i < todo_list.nr; i++)
		free(subjects[i]);
	free(subjects);
	hashmap_free(&subject2item, 1);
	todo_list_release(&todo_list);
 
	return res;
}