summaryrefslogtreecommitdiffstats
path: root/Utilities/cmcurl/lib/url.c
blob: 74813e8746f7c5b5f72d9fb51162fb9fff9500d3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at https://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ***************************************************************************/

#include "curl_setup.h"

#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_NET_IF_H
#include <net/if.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif

#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif

#ifdef __VMS
#include <in.h>
#include <inet.h>
#endif

#ifdef HAVE_SYS_UN_H
#include <sys/un.h>
#endif

#ifndef HAVE_SOCKET
#error "We can't compile without socket() support!"
#endif

#include <limits.h>

#ifdef USE_LIBIDN2
#include <idn2.h>

#elif defined(USE_WIN32_IDN)
/* prototype for curl_win32_idn_to_ascii() */
bool curl_win32_idn_to_ascii(const char *in, char **out);
#endif  /* USE_LIBIDN2 */

#include "urldata.h"
#include "netrc.h"

#include "formdata.h"
#include "mime.h"
#include "vtls/vtls.h"
#include "hostip.h"
#include "transfer.h"
#include "sendf.h"
#include "progress.h"
#include "cookie.h"
#include "strcase.h"
#include "strerror.h"
#include "escape.h"
#include "strtok.h"
#include "share.h"
#include "content_encoding.h"
#include "http_digest.h"
#include "http_negotiate.h"
#include "select.h"
#include "multiif.h"
#include "easyif.h"
#include "speedcheck.h"
#include "warnless.h"
#include "non-ascii.h"
#include "inet_pton.h"
#include "getinfo.h"

/* And now for the protocols */
#include "ftp.h"
#include "dict.h"
#include "telnet.h"
#include "tftp.h"
#include "http.h"
#include "http2.h"
#include "file.h"
#include "curl_ldap.h"
#include "ssh.h"
#include "imap.h"
#include "url.h"
#include "connect.h"
#include "inet_ntop.h"
#include "http_ntlm.h"
#include "curl_ntlm_wb.h"
#include "socks.h"
#include "curl_rtmp.h"
#include "gopher.h"
#include "http_proxy.h"
#include "conncache.h"
#include "multihandle.h"
#include "pipeline.h"
#include "dotdot.h"
#include "strdup.h"
#include "setopt.h"

/* The last 3 #include files should be in this order */
#include "curl_printf.h"
#include "curl_memory.h"
#include "memdebug.h"

static void conn_free(struct connectdata *conn);
static void free_fixed_hostname(struct hostname *host);
static void signalPipeClose(struct curl_llist *pipeline, bool pipe_broke);
static CURLcode parse_url_login(struct Curl_easy *data,
                                struct connectdata *conn,
                                char **userptr, char **passwdptr,
                                char **optionsptr);
static unsigned int get_protocol_family(unsigned int protocol);

/* Some parts of the code (e.g. chunked encoding) assume this buffer has at
 * more than just a few bytes to play with. Don't let it become too small or
 * bad things will happen.
 */
#if READBUFFER_SIZE < READBUFFER_MIN
# error READBUFFER_SIZE is too small
#endif


/*
 * Protocol table.
 */

static const struct Curl_handler * const protocols[] = {

#ifndef CURL_DISABLE_HTTP
  &Curl_handler_http,
#endif

#if defined(USE_SSL) && !defined(CURL_DISABLE_HTTP)
  &Curl_handler_https,
#endif

#ifndef CURL_DISABLE_FTP
  &Curl_handler_ftp,
#endif

#if defined(USE_SSL) && !defined(CURL_DISABLE_FTP)
  &Curl_handler_ftps,
#endif

#ifndef CURL_DISABLE_TELNET
  &Curl_handler_telnet,
#endif

#ifndef CURL_DISABLE_DICT
  &Curl_handler_dict,
#endif

#ifndef CURL_DISABLE_LDAP
  &Curl_handler_ldap,
#if !defined(CURL_DISABLE_LDAPS) && \
    ((defined(USE_OPENLDAP) && defined(USE_SSL)) || \
     (!defined(USE_OPENLDAP) && defined(HAVE_LDAP_SSL)))
  &Curl_handler_ldaps,
#endif
#endif

#ifndef CURL_DISABLE_FILE
  &Curl_handler_file,
#endif

#ifndef CURL_DISABLE_TFTP
  &Curl_handler_tftp,
#endif

#if defined(USE_LIBSSH2) || defined(USE_LIBSSH)
  &Curl_handler_scp,
#endif

#if defined(USE_LIBSSH2) || defined(USE_LIBSSH)
  &Curl_handler_sftp,
#endif

#ifndef CURL_DISABLE_IMAP
  &Curl_handler_imap,
#ifdef USE_SSL
  &Curl_handler_imaps,
#endif
#endif

#ifndef CURL_DISABLE_POP3
  &Curl_handler_pop3,
#ifdef USE_SSL
  &Curl_handler_pop3s,
#endif
#endif

#if !defined(CURL_DISABLE_SMB) && defined(USE_NTLM) && \
   (CURL_SIZEOF_CURL_OFF_T > 4) && \
   (!defined(USE_WINDOWS_SSPI) || defined(USE_WIN32_CRYPTO))
  &Curl_handler_smb,
#ifdef USE_SSL
  &Curl_handler_smbs,
#endif
#endif

#ifndef CURL_DISABLE_SMTP
  &Curl_handler_smtp,
#ifdef USE_SSL
  &Curl_handler_smtps,
#endif
#endif

#ifndef CURL_DISABLE_RTSP
  &Curl_handler_rtsp,
#endif

#ifndef CURL_DISABLE_GOPHER
  &Curl_handler_gopher,
#endif

#ifdef USE_LIBRTMP
  &Curl_handler_rtmp,
  &Curl_handler_rtmpt,
  &Curl_handler_rtmpe,
  &Curl_handler_rtmpte,
  &Curl_handler_rtmps,
  &Curl_handler_rtmpts,
#endif

  (struct Curl_handler *) NULL
};

/*
 * Dummy handler for undefined protocol schemes.
 */

static const struct Curl_handler Curl_handler_dummy = {
  "<no protocol>",                      /* scheme */
  ZERO_NULL,                            /* setup_connection */
  ZERO_NULL,                            /* do_it */
  ZERO_NULL,                            /* done */
  ZERO_NULL,                            /* do_more */
  ZERO_NULL,                            /* connect_it */
  ZERO_NULL,                            /* connecting */
  ZERO_NULL,                            /* doing */
  ZERO_NULL,                            /* proto_getsock */
  ZERO_NULL,                            /* doing_getsock */
  ZERO_NULL,                            /* domore_getsock */
  ZERO_NULL,                            /* perform_getsock */
  ZERO_NULL,                            /* disconnect */
  ZERO_NULL,                            /* readwrite */
  ZERO_NULL,                            /* connection_check */
  0,                                    /* defport */
  0,                                    /* protocol */
  PROTOPT_NONE                          /* flags */
};

void Curl_freeset(struct Curl_easy *data)
{
  /* Free all dynamic strings stored in the data->set substructure. */
  enum dupstring i;
  for(i = (enum dupstring)0; i < STRING_LAST; i++) {
    Curl_safefree(data->set.str[i]);
  }

  if(data->change.referer_alloc) {
    Curl_safefree(data->change.referer);
    data->change.referer_alloc = FALSE;
  }
  data->change.referer = NULL;
  if(data->change.url_alloc) {
    Curl_safefree(data->change.url);
    data->change.url_alloc = FALSE;
  }
  data->change.url = NULL;

  Curl_mime_cleanpart(&data->set.mimepost);
}

/*
 * This is the internal function curl_easy_cleanup() calls. This should
 * cleanup and free all resources associated with this sessionhandle.
 *
 * NOTE: if we ever add something that attempts to write to a socket or
 * similar here, we must ignore SIGPIPE first. It is currently only done
 * when curl_easy_perform() is invoked.
 */

CURLcode Curl_close(struct Curl_easy *data)
{
  struct Curl_multi *m;

  if(!data)
    return CURLE_OK;

  Curl_expire_clear(data); /* shut off timers */

  m = data->multi;

  if(m)
    /* This handle is still part of a multi handle, take care of this first
       and detach this handle from there. */
    curl_multi_remove_handle(data->multi, data);

  if(data->multi_easy)
    /* when curl_easy_perform() is used, it creates its own multi handle to
       use and this is the one */
    curl_multi_cleanup(data->multi_easy);

  /* Destroy the timeout list that is held in the easy handle. It is
     /normally/ done by curl_multi_remove_handle() but this is "just in
     case" */
  Curl_llist_destroy(&data->state.timeoutlist, NULL);

  data->magic = 0; /* force a clear AFTER the possibly enforced removal from
                      the multi handle, since that function uses the magic
                      field! */

  if(data->state.rangestringalloc)
    free(data->state.range);

  /* Free the pathbuffer */
  Curl_safefree(data->state.pathbuffer);
  data->state.path = NULL;

  /* freed here just in case DONE wasn't called */
  Curl_free_request_state(data);

  /* Close down all open SSL info and sessions */
  Curl_ssl_close_all(data);
  Curl_safefree(data->state.first_host);
  Curl_safefree(data->state.scratch);
  Curl_ssl_free_certinfo(data);

  /* Cleanup possible redirect junk */
  free(data->req.newurl);
  data->req.newurl = NULL;

  if(data->change.referer_alloc) {
    Curl_safefree(data->change.referer);
    data->change.referer_alloc = FALSE;
  }
  data->change.referer = NULL;

  if(data->change.url_alloc) {
    Curl_safefree(data->change.url);
    data->change.url_alloc = FALSE;
  }
  data->change.url = NULL;

  Curl_safefree(data->state.buffer);
  Curl_safefree(data->state.headerbuff);

  Curl_flush_cookies(data, 1);

  Curl_digest_cleanup(data);

  Curl_safefree(data->info.contenttype);
  Curl_safefree(data->info.wouldredirect);

  /* this destroys the channel and we cannot use it anymore after this */
  Curl_resolver_cleanup(data->state.resolver);

  Curl_http2_cleanup_dependencies(data);
  Curl_convert_close(data);

  /* No longer a dirty share, if it exists */
  if(data->share) {
    Curl_share_lock(data, CURL_LOCK_DATA_SHARE, CURL_LOCK_ACCESS_SINGLE);
    data->share->dirty--;
    Curl_share_unlock(data, CURL_LOCK_DATA_SHARE);
  }

  /* destruct wildcard structures if it is needed */
  Curl_wildcard_dtor(&data->wildcard);
  Curl_freeset(data);
  free(data);
  return CURLE_OK;
}

/*
 * Initialize the UserDefined fields within a Curl_easy.
 * This may be safely called on a new or existing Curl_easy.
 */
CURLcode Curl_init_userdefined(struct Curl_easy *data)
{
  struct UserDefined *set = &data->set;
  CURLcode result = CURLE_OK;

  set->out = stdout; /* default output to stdout */
  set->in_set = stdin;  /* default input from stdin */
  set->err  = stderr;  /* default stderr to stderr */

  /* use fwrite as default function to store output */
  set->fwrite_func = (curl_write_callback)fwrite;

  /* use fread as default function to read input */
  set->fread_func_set = (curl_read_callback)fread;
  set->is_fread_set = 0;
  set->is_fwrite_set = 0;

  set->seek_func = ZERO_NULL;
  set->seek_client = ZERO_NULL;

  /* conversion callbacks for non-ASCII hosts */
  set->convfromnetwork = ZERO_NULL;
  set->convtonetwork   = ZERO_NULL;
  set->convfromutf8    = ZERO_NULL;

  set->filesize = -1;        /* we don't know the size */
  set->postfieldsize = -1;   /* unknown size */
  set->maxredirs = -1;       /* allow any amount by default */

  set->httpreq = HTTPREQ_GET; /* Default HTTP request */
  set->rtspreq = RTSPREQ_OPTIONS; /* Default RTSP request */
  set->ftp_use_epsv = TRUE;   /* FTP defaults to EPSV operations */
  set->ftp_use_eprt = TRUE;   /* FTP defaults to EPRT operations */
  set->ftp_use_pret = FALSE;  /* mainly useful for drftpd servers */
  set->ftp_filemethod = FTPFILE_MULTICWD;

  set->dns_cache_timeout = 60; /* Timeout every 60 seconds by default */

  /* Set the default size of the SSL session ID cache */
  set->general_ssl.max_ssl_sessions = 5;

  set->proxyport = 0;
  set->proxytype = CURLPROXY_HTTP; /* defaults to HTTP proxy */
  set->httpauth = CURLAUTH_BASIC;  /* defaults to basic */
  set->proxyauth = CURLAUTH_BASIC; /* defaults to basic */

  /* SOCKS5 proxy auth defaults to username/password + GSS-API */
  set->socks5auth = CURLAUTH_BASIC | CURLAUTH_GSSAPI;

  /* make libcurl quiet by default: */
  set->hide_progress = TRUE;  /* CURLOPT_NOPROGRESS changes these */

  Curl_mime_initpart(&set->mimepost, data);

  /*
   * libcurl 7.10 introduced SSL verification *by default*! This needs to be
   * switched off unless wanted.
   */
  set->ssl.primary.verifypeer = TRUE;
  set->ssl.primary.verifyhost = TRUE;
#ifdef USE_TLS_SRP
  set->ssl.authtype = CURL_TLSAUTH_NONE;
#endif
  set->ssh_auth_types = CURLSSH_AUTH_DEFAULT; /* defaults to any auth
                                                      type */
  set->ssl.primary.sessionid = TRUE; /* session ID caching enabled by
                                        default */
  set->proxy_ssl = set->ssl;

  set->new_file_perms = 0644;    /* Default permissions */
  set->new_directory_perms = 0755; /* Default permissions */

  /* for the *protocols fields we don't use the CURLPROTO_ALL convenience
     define since we internally only use the lower 16 bits for the passed
     in bitmask to not conflict with the private bits */
  set->allowed_protocols = CURLPROTO_ALL;
  set->redir_protocols = CURLPROTO_ALL &  /* All except FILE, SCP and SMB */
                          ~(CURLPROTO_FILE | CURLPROTO_SCP | CURLPROTO_SMB |
                            CURLPROTO_SMBS);

#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
  /*
   * disallow unprotected protection negotiation NEC reference implementation
   * seem not to follow rfc1961 section 4.3/4.4
   */
  set->socks5_gssapi_nec = FALSE;
#endif

  /* This is our preferred CA cert bundle/path since install time */
#if defined(CURL_CA_BUNDLE)
  result = Curl_setstropt(&set->str[STRING_SSL_CAFILE_ORIG], CURL_CA_BUNDLE);
  if(result)
    return result;

  result = Curl_setstropt(&set->str[STRING_SSL_CAFILE_PROXY], CURL_CA_BUNDLE);
  if(result)
    return result;
#endif
#if defined(CURL_CA_PATH)
  result = Curl_setstropt(&set->str[STRING_SSL_CAPATH_ORIG], CURL_CA_PATH);
  if(result)
    return result;

  result = Curl_setstropt(&set->str[STRING_SSL_CAPATH_PROXY], CURL_CA_PATH);
  if(result)
    return result;
#endif

  set->wildcard_enabled = FALSE;
  set->chunk_bgn      = ZERO_NULL;
  set->chunk_end      = ZERO_NULL;

  /* tcp keepalives are disabled by default, but provide reasonable values for
   * the interval and idle times.
   */
  set->tcp_keepalive = FALSE;
  set->tcp_keepintvl = 60;
  set->tcp_keepidle = 60;
  set->tcp_fastopen = FALSE;
  set->tcp_nodelay = TRUE;

  set->ssl_enable_npn = TRUE;
  set->ssl_enable_alpn = TRUE;

  set->expect_100_timeout = 1000L; /* Wait for a second by default. */
  set->sep_headers = TRUE; /* separated header lists by default */
  set->buffer_size = READBUFFER_SIZE;

  Curl_http2_init_userset(set);
  return result;
}

/**
 * Curl_open()
 *
 * @param curl is a pointer to a sessionhandle pointer that gets set by this
 * function.
 * @return CURLcode
 */

CURLcode Curl_open(struct Curl_easy **curl)
{
  CURLcode result;
  struct Curl_easy *data;

  /* Very simple start-up: alloc the struct, init it with zeroes and return */
  data = calloc(1, sizeof(struct Curl_easy));
  if(!data) {
    /* this is a very serious error */
    DEBUGF(fprintf(stderr, "Error: calloc of Curl_easy failed\n"));
    return CURLE_OUT_OF_MEMORY;
  }

  data->magic = CURLEASY_MAGIC_NUMBER;

  result = Curl_resolver_init(&data->state.resolver);
  if(result) {
    DEBUGF(fprintf(stderr, "Error: resolver_init failed\n"));
    free(data);
    return result;
  }

  /* We do some initial setup here, all those fields that can't be just 0 */

  data->state.buffer = malloc(READBUFFER_SIZE + 1);
  if(!data->state.buffer) {
    DEBUGF(fprintf(stderr, "Error: malloc of buffer failed\n"));
    result = CURLE_OUT_OF_MEMORY;
  }
  else {
    data->state.headerbuff = malloc(HEADERSIZE);
    if(!data->state.headerbuff) {
      DEBUGF(fprintf(stderr, "Error: malloc of headerbuff failed\n"));
      result = CURLE_OUT_OF_MEMORY;
    }
    else {
      result = Curl_init_userdefined(data);

      data->state.headersize = HEADERSIZE;
      Curl_convert_init(data);
      Curl_initinfo(data);

      /* most recent connection is not yet defined */
      data->state.lastconnect = NULL;

      data->progress.flags |= PGRS_HIDE;
      data->state.current_speed = -1; /* init to negative == impossible */
      data->set.fnmatch = ZERO_NULL;
      data->set.maxconnects = DEFAULT_CONNCACHE_SIZE; /* for easy handles */

      Curl_http2_init_state(&data->state);
    }
  }

  if(result) {
    Curl_resolver_cleanup(data->state.resolver);
    free(data->state.buffer);
    free(data->state.headerbuff);
    Curl_freeset(data);
    free(data);
    data = NULL;
  }
  else
    *curl = data;

  return result;
}

#ifdef USE_RECV_BEFORE_SEND_WORKAROUND
static void conn_reset_postponed_data(struct connectdata *conn, int num)
{
  struct postponed_data * const psnd = &(conn->postponed[num]);
  if(psnd->buffer) {
    DEBUGASSERT(psnd->allocated_size > 0);
    DEBUGASSERT(psnd->recv_size <= psnd->allocated_size);
    DEBUGASSERT(psnd->recv_size ?
                (psnd->recv_processed < psnd->recv_size) :
                (psnd->recv_processed == 0));
    DEBUGASSERT(psnd->bindsock != CURL_SOCKET_BAD);
    free(psnd->buffer);
    psnd->buffer = NULL;
    psnd->allocated_size = 0;
    psnd->recv_size = 0;
    psnd->recv_processed = 0;
#ifdef DEBUGBUILD
    psnd->bindsock = CURL_SOCKET_BAD; /* used only for DEBUGASSERT */
#endif /* DEBUGBUILD */
  }
  else {
    DEBUGASSERT(psnd->allocated_size == 0);
    DEBUGASSERT(psnd->recv_size == 0);
    DEBUGASSERT(psnd->recv_processed == 0);
    DEBUGASSERT(psnd->bindsock == CURL_SOCKET_BAD);
  }
}

static void conn_reset_all_postponed_data(struct connectdata *conn)
{
  conn_reset_postponed_data(conn, 0);
  conn_reset_postponed_data(conn, 1);
}
#else  /* ! USE_RECV_BEFORE_SEND_WORKAROUND */
/* Use "do-nothing" macro instead of function when workaround not used */
#define conn_reset_all_postponed_data(c) do {} WHILE_FALSE
#endif /* ! USE_RECV_BEFORE_SEND_WORKAROUND */

static void conn_free(struct connectdata *conn)
{
  if(!conn)
    return;

  /* possible left-overs from the async name resolvers */
  Curl_resolver_cancel(conn);

  /* close the SSL stuff before we close any sockets since they will/may
     write to the sockets */
  Curl_ssl_close(conn, FIRSTSOCKET);
  Curl_ssl_close(conn, SECONDARYSOCKET);

  /* close possibly still open sockets */
  if(CURL_SOCKET_BAD != conn->sock[SECONDARYSOCKET])
    Curl_closesocket(conn, conn->sock[SECONDARYSOCKET]);
  if(CURL_SOCKET_BAD != conn->sock[FIRSTSOCKET])
    Curl_closesocket(conn, conn->sock[FIRSTSOCKET]);
  if(CURL_SOCKET_BAD != conn->tempsock[0])
    Curl_closesocket(conn, conn->tempsock[0]);
  if(CURL_SOCKET_BAD != conn->tempsock[1])
    Curl_closesocket(conn, conn->tempsock[1]);

#if !defined(CURL_DISABLE_HTTP) && defined(USE_NTLM) && \
    defined(NTLM_WB_ENABLED)
  Curl_ntlm_wb_cleanup(conn);
#endif

  Curl_safefree(conn->user);
  Curl_safefree(conn->passwd);
  Curl_safefree(conn->oauth_bearer);
  Curl_safefree(conn->options);
  Curl_safefree(conn->http_proxy.user);
  Curl_safefree(conn->socks_proxy.user);
  Curl_safefree(conn->http_proxy.passwd);
  Curl_safefree(conn->socks_proxy.passwd);
  Curl_safefree(conn->allocptr.proxyuserpwd);
  Curl_safefree(conn->allocptr.uagent);
  Curl_safefree(conn->allocptr.userpwd);
  Curl_safefree(conn->allocptr.accept_encoding);
  Curl_safefree(conn->allocptr.te);
  Curl_safefree(conn->allocptr.rangeline);
  Curl_safefree(conn->allocptr.ref);
  Curl_safefree(conn->allocptr.host);
  Curl_safefree(conn->allocptr.cookiehost);
  Curl_safefree(conn->allocptr.rtsp_transport);
  Curl_safefree(conn->trailer);
  Curl_safefree(conn->host.rawalloc); /* host name buffer */
  Curl_safefree(conn->conn_to_host.rawalloc); /* host name buffer */
  Curl_safefree(conn->secondaryhostname);
  Curl_safefree(conn->http_proxy.host.rawalloc); /* http proxy name buffer */
  Curl_safefree(conn->socks_proxy.host.rawalloc); /* socks proxy name buffer */
  Curl_safefree(conn->master_buffer);
  Curl_safefree(conn->connect_state);

  conn_reset_all_postponed_data(conn);

  Curl_llist_destroy(&conn->send_pipe, NULL);
  Curl_llist_destroy(&conn->recv_pipe, NULL);

  Curl_safefree(conn->localdev);
  Curl_free_primary_ssl_config(&conn->ssl_config);
  Curl_free_primary_ssl_config(&conn->proxy_ssl_config);

#ifdef USE_UNIX_SOCKETS
  Curl_safefree(conn->unix_domain_socket);
#endif

#ifdef USE_SSL
  Curl_safefree(conn->ssl_extra);
#endif
  free(conn); /* free all the connection oriented data */
}

/*
 * Disconnects the given connection. Note the connection may not be the
 * primary connection, like when freeing room in the connection cache or
 * killing of a dead old connection.
 *
 * This function MUST NOT reset state in the Curl_easy struct if that
 * isn't strictly bound to the life-time of *this* particular connection.
 *
 */

CURLcode Curl_disconnect(struct connectdata *conn, bool dead_connection)
{
  struct Curl_easy *data;
  if(!conn)
    return CURLE_OK; /* this is closed and fine already */
  data = conn->data;

  if(!data) {
    DEBUGF(fprintf(stderr, "DISCONNECT without easy handle, ignoring\n"));
    return CURLE_OK;
  }

  /*
   * If this connection isn't marked to force-close, leave it open if there
   * are other users of it
   */
  if(!conn->bits.close &&
     (conn->send_pipe.size + conn->recv_pipe.size)) {
    DEBUGF(infof(data, "Curl_disconnect, usecounter: %d\n",
                 conn->send_pipe.size + conn->recv_pipe.size));
    return CURLE_OK;
  }

  if(conn->dns_entry != NULL) {
    Curl_resolv_unlock(data, conn->dns_entry);
    conn->dns_entry = NULL;
  }

  Curl_hostcache_prune(data); /* kill old DNS cache entries */

#if !defined(CURL_DISABLE_HTTP) && defined(USE_NTLM)
  /* Cleanup NTLM connection-related data */
  Curl_http_ntlm_cleanup(conn);
#endif

  if(conn->handler->disconnect)
    /* This is set if protocol-specific cleanups should be made */
    conn->handler->disconnect(conn, dead_connection);

    /* unlink ourselves! */
  infof(data, "Closing connection %ld\n", conn->connection_id);
  Curl_conncache_remove_conn(conn, TRUE);

  free_fixed_hostname(&conn->host);
  free_fixed_hostname(&conn->conn_to_host);
  free_fixed_hostname(&conn->http_proxy.host);
  free_fixed_hostname(&conn->socks_proxy.host);

  Curl_ssl_close(conn, FIRSTSOCKET);

  /* Indicate to all handles on the pipe that we're dead */
  if(Curl_pipeline_wanted(data->multi, CURLPIPE_ANY)) {
    signalPipeClose(&conn->send_pipe, TRUE);
    signalPipeClose(&conn->recv_pipe, TRUE);
  }

  conn_free(conn);

  return CURLE_OK;
}

/*
 * This function should return TRUE if the socket is to be assumed to
 * be dead. Most commonly this happens when the server has closed the
 * connection due to inactivity.
 */
static bool SocketIsDead(curl_socket_t sock)
{
  int sval;
  bool ret_val = TRUE;

  sval = SOCKET_READABLE(sock, 0);
  if(sval == 0)
    /* timeout */
    ret_val = FALSE;

  return ret_val;
}

/*
 * IsPipeliningPossible()
 *
 * Return a bitmask with the available pipelining and multiplexing options for
 * the given requested connection.
 */
static int IsPipeliningPossible(const struct Curl_easy *handle,
                                const struct connectdata *conn)
{
  int avail = 0;

  /* If a HTTP protocol and pipelining is enabled */
  if((conn->handler->protocol & PROTO_FAMILY_HTTP) &&
     (!conn->bits.protoconnstart || !conn->bits.close)) {

    if(Curl_pipeline_wanted(handle->multi, CURLPIPE_HTTP1) &&
       (handle->set.httpversion != CURL_HTTP_VERSION_1_0) &&
       (handle->set.httpreq == HTTPREQ_GET ||
        handle->set.httpreq == HTTPREQ_HEAD))
      /* didn't ask for HTTP/1.0 and a GET or HEAD */
      avail |= CURLPIPE_HTTP1;

    if(Curl_pipeline_wanted(handle->multi, CURLPIPE_MULTIPLEX) &&
       (handle->set.httpversion >= CURL_HTTP_VERSION_2))
      /* allows HTTP/2 */
      avail |= CURLPIPE_MULTIPLEX;
  }
  return avail;
}

int Curl_removeHandleFromPipeline(struct Curl_easy *handle,
                                  struct curl_llist *pipeline)
{
  if(pipeline) {
    struct curl_llist_element *curr;

    curr = pipeline->head;
    while(curr) {
      if(curr->ptr == handle) {
        Curl_llist_remove(pipeline, curr, NULL);
        return 1; /* we removed a handle */
      }
      curr = curr->next;
    }
  }

  return 0;
}

#if 0 /* this code is saved here as it is useful for debugging purposes */
static void Curl_printPipeline(struct curl_llist *pipeline)
{
  struct curl_llist_element *curr;

  curr = pipeline->head;
  while(curr) {
    struct Curl_easy *data = (struct Curl_easy *) curr->ptr;
    infof(data, "Handle in pipeline: %s\n", data->state.path);
    curr = curr->next;
  }
}
#endif

static struct Curl_easy* gethandleathead(struct curl_llist *pipeline)
{
  struct curl_llist_element *curr = pipeline->head;
  if(curr) {
    return (struct Curl_easy *) curr->ptr;
  }

  return NULL;
}

/* remove the specified connection from all (possible) pipelines and related
   queues */
void Curl_getoff_all_pipelines(struct Curl_easy *data,
                               struct connectdata *conn)
{
  bool recv_head = (conn->readchannel_inuse &&
                    Curl_recvpipe_head(data, conn));
  bool send_head = (conn->writechannel_inuse &&
                    Curl_sendpipe_head(data, conn));

  if(Curl_removeHandleFromPipeline(data, &conn->recv_pipe) && recv_head)
    Curl_pipeline_leave_read(conn);
  if(Curl_removeHandleFromPipeline(data, &conn->send_pipe) && send_head)
    Curl_pipeline_leave_write(conn);
}

static void signalPipeClose(struct curl_llist *pipeline, bool pipe_broke)
{
  struct curl_llist_element *curr;

  if(!pipeline)
    return;

  curr = pipeline->head;
  while(curr) {
    struct curl_llist_element *next = curr->next;
    struct Curl_easy *data = (struct Curl_easy *) curr->ptr;

#ifdef DEBUGBUILD /* debug-only code */
    if(data->magic != CURLEASY_MAGIC_NUMBER) {
      /* MAJOR BADNESS */
      infof(data, "signalPipeClose() found BAAD easy handle\n");
    }
#endif

    if(pipe_broke)
      data->state.pipe_broke = TRUE;
    Curl_multi_handlePipeBreak(data);
    Curl_llist_remove(pipeline, curr, NULL);
    curr = next;
  }
}

static bool
proxy_info_matches(const struct proxy_info* data,
                   const struct proxy_info* needle)
{
  if((data->proxytype == needle->proxytype) &&
     (data->port == needle->port) &&
     Curl_safe_strcasecompare(data->host.name, needle->host.name))
    return TRUE;

  return FALSE;
}

/*
 * This function checks if the given connection is dead and extracts it from
 * the connection cache if so.
 *
 * When this is called as a Curl_conncache_foreach() callback, the connection
 * cache lock is held!
 *
 * Returns TRUE if the connection was dead and extracted.
 */
static bool extract_if_dead(struct connectdata *conn,
                            struct Curl_easy *data)
{
  size_t pipeLen = conn->send_pipe.size + conn->recv_pipe.size;
  if(!pipeLen && !conn->inuse) {
    /* The check for a dead socket makes sense only if there are no
       handles in pipeline and the connection isn't already marked in
       use */
    bool dead;

    if(conn->handler->connection_check) {
      /* The protocol has a special method for checking the state of the
         connection. Use it to check if the connection is dead. */
      unsigned int state;

      state = conn->handler->connection_check(conn, CONNCHECK_ISDEAD);
      dead = (state & CONNRESULT_DEAD);
    }
    else {
      /* Use the general method for determining the death of a connection */
      dead = SocketIsDead(conn->sock[FIRSTSOCKET]);
    }

    if(dead) {
      conn->data = data;
      infof(data, "Connection %ld seems to be dead!\n", conn->connection_id);
      Curl_conncache_remove_conn(conn, FALSE);
      return TRUE;
    }
  }
  return FALSE;
}

struct prunedead {
  struct Curl_easy *data;
  struct connectdata *extracted;
};

/*
 * Wrapper to use extract_if_dead() function in Curl_conncache_foreach()
 *
 */
static int call_extract_if_dead(struct connectdata *conn, void *param)
{
  struct prunedead *p = (struct prunedead *)param;
  if(extract_if_dead(conn, p->data)) {
    /* stop the iteration here, pass back the connection that was extracted */
    p->extracted = conn;
    return 1;
  }
  return 0; /* continue iteration */
}

/*
 * This function scans the connection cache for half-open/dead connections,
 * closes and removes them.
 * The cleanup is done at most once per second.
 */
static void prune_dead_connections(struct Curl_easy *data)
{
  struct curltime now = Curl_now();
  time_t elapsed = Curl_timediff(now, data->state.conn_cache->last_cleanup);

  if(elapsed >= 1000L) {
    struct prunedead prune;
    prune.data = data;
    prune.extracted = NULL;
    while(Curl_conncache_foreach(data, data->state.conn_cache, &prune,
                                 call_extract_if_dead)) {
      /* disconnect it */
      (void)Curl_disconnect(prune.extracted, /* dead_connection */TRUE);
    }
    data->state.conn_cache->last_cleanup = now;
  }
}


static size_t max_pipeline_length(struct Curl_multi *multi)
{
  return multi ? multi->max_pipeline_length : 0;
}


/*
 * Given one filled in connection struct (named needle), this function should
 * detect if there already is one that has all the significant details
 * exactly the same and thus should be used instead.
 *
 * If there is a match, this function returns TRUE - and has marked the
 * connection as 'in-use'. It must later be called with ConnectionDone() to
 * return back to 'idle' (unused) state.
 *
 * The force_reuse flag is set if the connection must be used, even if
 * the pipelining strategy wants to open a new connection instead of reusing.
 */
static bool
ConnectionExists(struct Curl_easy *data,
                 struct connectdata *needle,
                 struct connectdata **usethis,
                 bool *force_reuse,
                 bool *waitpipe)
{
  struct connectdata *check;
  struct connectdata *chosen = 0;
  bool foundPendingCandidate = FALSE;
  int canpipe = IsPipeliningPossible(data, needle);
  struct connectbundle *bundle;

#ifdef USE_NTLM
  bool wantNTLMhttp = ((data->state.authhost.want &
                      (CURLAUTH_NTLM | CURLAUTH_NTLM_WB)) &&
                      (needle->handler->protocol & PROTO_FAMILY_HTTP));
  bool wantProxyNTLMhttp = (needle->bits.proxy_user_passwd &&
                           ((data->state.authproxy.want &
                           (CURLAUTH_NTLM | CURLAUTH_NTLM_WB)) &&
                           (needle->handler->protocol & PROTO_FAMILY_HTTP)));
#endif

  *force_reuse = FALSE;
  *waitpipe = FALSE;

  /* We can't pipeline if the site is blacklisted */
  if((canpipe & CURLPIPE_HTTP1) &&
     Curl_pipeline_site_blacklisted(data, needle))
    canpipe &= ~ CURLPIPE_HTTP1;

  /* Look up the bundle with all the connections to this particular host.
     Locks the connection cache, beware of early returns! */
  bundle = Curl_conncache_find_bundle(needle, data->state.conn_cache);
  if(bundle) {
    /* Max pipe length is zero (unlimited) for multiplexed connections */
    size_t max_pipe_len = (bundle->multiuse != BUNDLE_MULTIPLEX)?
      max_pipeline_length(data->multi):0;
    size_t best_pipe_len = max_pipe_len;
    struct curl_llist_element *curr;

    infof(data, "Found bundle for host %s: %p [%s]\n",
          (needle->bits.conn_to_host ? needle->conn_to_host.name :
           needle->host.name), (void *)bundle,
          (bundle->multiuse == BUNDLE_PIPELINING ?
           "can pipeline" :
           (bundle->multiuse == BUNDLE_MULTIPLEX ?
            "can multiplex" : "serially")));

    /* We can't pipeline if we don't know anything about the server */
    if(canpipe) {
      if(bundle->multiuse <= BUNDLE_UNKNOWN) {
        if((bundle->multiuse == BUNDLE_UNKNOWN) && data->set.pipewait) {
          infof(data, "Server doesn't support multi-use yet, wait\n");
          *waitpipe = TRUE;
          Curl_conncache_unlock(needle);
          return FALSE; /* no re-use */
        }

        infof(data, "Server doesn't support multi-use (yet)\n");
        canpipe = 0;
      }
      if((bundle->multiuse == BUNDLE_PIPELINING) &&
         !Curl_pipeline_wanted(data->multi, CURLPIPE_HTTP1)) {
        /* not asked for, switch off */
        infof(data, "Could pipeline, but not asked to!\n");
        canpipe = 0;
      }
      else if((bundle->multiuse == BUNDLE_MULTIPLEX) &&
              !Curl_pipeline_wanted(data->multi, CURLPIPE_MULTIPLEX)) {
        infof(data, "Could multiplex, but not asked to!\n");
        canpipe = 0;
      }
    }

    curr = bundle->conn_list.head;
    while(curr) {
      bool match = FALSE;
      size_t pipeLen;

      /*
       * Note that if we use a HTTP proxy in normal mode (no tunneling), we
       * check connections to that proxy and not to the actual remote server.
       */
      check = curr->ptr;
      curr = curr->next;

      if(extract_if_dead(check, data)) {
        /* disconnect it */
        (void)Curl_disconnect(check, /* dead_connection */TRUE);
        continue;
      }

      pipeLen = check->send_pipe.size + check->recv_pipe.size;

      if(canpipe) {
        if(check->bits.protoconnstart && check->bits.close)
          continue;

        if(!check->bits.multiplex) {
          /* If not multiplexing, make sure the connection is fine for HTTP/1
             pipelining */
          struct Curl_easy* sh = gethandleathead(&check->send_pipe);
          struct Curl_easy* rh = gethandleathead(&check->recv_pipe);
          if(sh) {
            if(!(IsPipeliningPossible(sh, check) & CURLPIPE_HTTP1))
              continue;
          }
          else if(rh) {
            if(!(IsPipeliningPossible(rh, check) & CURLPIPE_HTTP1))
              continue;
          }
        }
      }
      else {
        if(pipeLen > 0) {
          /* can only happen within multi handles, and means that another easy
             handle is using this connection */
          continue;
        }

        if(Curl_resolver_asynch()) {
          /* ip_addr_str[0] is NUL only if the resolving of the name hasn't
             completed yet and until then we don't re-use this connection */
          if(!check->ip_addr_str[0]) {
            infof(data,
                  "Connection #%ld is still name resolving, can't reuse\n",
                  check->connection_id);
            continue;
          }
        }

        if((check->sock[FIRSTSOCKET] == CURL_SOCKET_BAD) ||
           check->bits.close) {
          if(!check->bits.close)
            foundPendingCandidate = TRUE;
          /* Don't pick a connection that hasn't connected yet or that is going
             to get closed. */
          infof(data, "Connection #%ld isn't open enough, can't reuse\n",
                check->connection_id);
#ifdef DEBUGBUILD
          if(check->recv_pipe.size > 0) {
            infof(data,
                  "BAD! Unconnected #%ld has a non-empty recv pipeline!\n",
                  check->connection_id);
          }
#endif
          continue;
        }
      }

#ifdef USE_UNIX_SOCKETS
      if(needle->unix_domain_socket) {
        if(!check->unix_domain_socket)
          continue;
        if(strcmp(needle->unix_domain_socket, check->unix_domain_socket))
          continue;
        if(needle->abstract_unix_socket != check->abstract_unix_socket)
          continue;
      }
      else if(check->unix_domain_socket)
        continue;
#endif

      if((needle->handler->flags&PROTOPT_SSL) !=
         (check->handler->flags&PROTOPT_SSL))
        /* don't do mixed SSL and non-SSL connections */
        if(get_protocol_family(check->handler->protocol) !=
           needle->handler->protocol || !check->tls_upgraded)
          /* except protocols that have been upgraded via TLS */
          continue;

      if(needle->bits.httpproxy != check->bits.httpproxy ||
         needle->bits.socksproxy != check->bits.socksproxy)
        continue;

      if(needle->bits.socksproxy && !proxy_info_matches(&needle->socks_proxy,
                                                        &check->socks_proxy))
        continue;

      if(needle->bits.conn_to_host != check->bits.conn_to_host)
        /* don't mix connections that use the "connect to host" feature and
         * connections that don't use this feature */
        continue;

      if(needle->bits.conn_to_port != check->bits.conn_to_port)
        /* don't mix connections that use the "connect to port" feature and
         * connections that don't use this feature */
        continue;

      if(needle->bits.httpproxy) {
        if(!proxy_info_matches(&needle->http_proxy, &check->http_proxy))
          continue;

        if(needle->bits.tunnel_proxy != check->bits.tunnel_proxy)
          continue;

        if(needle->http_proxy.proxytype == CURLPROXY_HTTPS) {
          /* use https proxy */
          if(needle->handler->flags&PROTOPT_SSL) {
            /* use double layer ssl */
            if(!Curl_ssl_config_matches(&needle->proxy_ssl_config,
                                        &check->proxy_ssl_config))
              continue;
            if(check->proxy_ssl[FIRSTSOCKET].state != ssl_connection_complete)
              continue;
          }
          else {
            if(!Curl_ssl_config_matches(&needle->ssl_config,
                                        &check->ssl_config))
              continue;
            if(check->ssl[FIRSTSOCKET].state != ssl_connection_complete)
              continue;
          }
        }
      }

      if(!canpipe && check->inuse)
        /* this request can't be pipelined but the checked connection is
           already in use so we skip it */
        continue;

      if((check->inuse) && (check->data->multi != needle->data->multi))
        /* this could be subject for pipeline/multiplex use, but only
           if they belong to the same multi handle */
        continue;

      if(needle->localdev || needle->localport) {
        /* If we are bound to a specific local end (IP+port), we must not
           re-use a random other one, although if we didn't ask for a
           particular one we can reuse one that was bound.

           This comparison is a bit rough and too strict. Since the input
           parameters can be specified in numerous ways and still end up the
           same it would take a lot of processing to make it really accurate.
           Instead, this matching will assume that re-uses of bound connections
           will most likely also re-use the exact same binding parameters and
           missing out a few edge cases shouldn't hurt anyone very much.
        */
        if((check->localport != needle->localport) ||
           (check->localportrange != needle->localportrange) ||
           (needle->localdev &&
            (!check->localdev || strcmp(check->localdev, needle->localdev))))
          continue;
      }

      if(!(needle->handler->flags & PROTOPT_CREDSPERREQUEST)) {
        /* This protocol requires credentials per connection,
           so verify that we're using the same name and password as well */
        if(strcmp(needle->user, check->user) ||
           strcmp(needle->passwd, check->passwd)) {
          /* one of them was different */
          continue;
        }
      }

      if(!needle->bits.httpproxy || (needle->handler->flags&PROTOPT_SSL) ||
         needle->bits.tunnel_proxy) {
        /* The requested connection does not use a HTTP proxy or it uses SSL or
           it is a non-SSL protocol tunneled or it is a non-SSL protocol which
           is allowed to be upgraded via TLS */

        if((strcasecompare(needle->handler->scheme, check->handler->scheme) ||
            (get_protocol_family(check->handler->protocol) ==
             needle->handler->protocol && check->tls_upgraded)) &&
           (!needle->bits.conn_to_host || strcasecompare(
            needle->conn_to_host.name, check->conn_to_host.name)) &&
           (!needle->bits.conn_to_port ||
             needle->conn_to_port == check->conn_to_port) &&
           strcasecompare(needle->host.name, check->host.name) &&
           needle->remote_port == check->remote_port) {
          /* The schemes match or the the protocol family is the same and the
             previous connection was TLS upgraded, and the hostname and host
             port match */
          if(needle->handler->flags & PROTOPT_SSL) {
            /* This is a SSL connection so verify that we're using the same
               SSL options as well */
            if(!Curl_ssl_config_matches(&needle->ssl_config,
                                        &check->ssl_config)) {
              DEBUGF(infof(data,
                           "Connection #%ld has different SSL parameters, "
                           "can't reuse\n",
                           check->connection_id));
              continue;
            }
            if(check->ssl[FIRSTSOCKET].state != ssl_connection_complete) {
              foundPendingCandidate = TRUE;
              DEBUGF(infof(data,
                           "Connection #%ld has not started SSL connect, "
                           "can't reuse\n",
                           check->connection_id));
              continue;
            }
          }
          match = TRUE;
        }
      }
      else {
        /* The requested connection is using the same HTTP proxy in normal
           mode (no tunneling) */
        match = TRUE;
      }

      if(match) {
#if defined(USE_NTLM)
        /* If we are looking for an HTTP+NTLM connection, check if this is
           already authenticating with the right credentials. If not, keep
           looking so that we can reuse NTLM connections if
           possible. (Especially we must not reuse the same connection if
           partway through a handshake!) */
        if(wantNTLMhttp) {
          if(strcmp(needle->user, check->user) ||
             strcmp(needle->passwd, check->passwd))
            continue;
        }
        else if(check->ntlm.state != NTLMSTATE_NONE) {
          /* Connection is using NTLM auth but we don't want NTLM */
          continue;
        }

        /* Same for Proxy NTLM authentication */
        if(wantProxyNTLMhttp) {
          /* Both check->http_proxy.user and check->http_proxy.passwd can be
           * NULL */
          if(!check->http_proxy.user || !check->http_proxy.passwd)
            continue;

          if(strcmp(needle->http_proxy.user, check->http_proxy.user) ||
             strcmp(needle->http_proxy.passwd, check->http_proxy.passwd))
            continue;
        }
        else if(check->proxyntlm.state != NTLMSTATE_NONE) {
          /* Proxy connection is using NTLM auth but we don't want NTLM */
          continue;
        }

        if(wantNTLMhttp || wantProxyNTLMhttp) {
          /* Credentials are already checked, we can use this connection */
          chosen = check;

          if((wantNTLMhttp &&
             (check->ntlm.state != NTLMSTATE_NONE)) ||
              (wantProxyNTLMhttp &&
               (check->proxyntlm.state != NTLMSTATE_NONE))) {
            /* We must use this connection, no other */
            *force_reuse = TRUE;
            break;
          }

          /* Continue look up for a better connection */
          continue;
        }
#endif
        if(canpipe) {
          /* We can pipeline if we want to. Let's continue looking for
             the optimal connection to use, i.e the shortest pipe that is not
             blacklisted. */

          if(pipeLen == 0) {
            /* We have the optimal connection. Let's stop looking. */
            chosen = check;
            break;
          }

          /* We can't use the connection if the pipe is full */
          if(max_pipe_len && (pipeLen >= max_pipe_len)) {
            infof(data, "Pipe is full, skip (%zu)\n", pipeLen);
            continue;
          }
#ifdef USE_NGHTTP2
          /* If multiplexed, make sure we don't go over concurrency limit */
          if(check->bits.multiplex) {
            /* Multiplexed connections can only be HTTP/2 for now */
            struct http_conn *httpc = &check->proto.httpc;
            if(pipeLen >= httpc->settings.max_concurrent_streams) {
              infof(data, "MAX_CONCURRENT_STREAMS reached, skip (%zu)\n",
                    pipeLen);
              continue;
            }
          }
#endif
          /* We can't use the connection if the pipe is penalized */
          if(Curl_pipeline_penalized(data, check)) {
            infof(data, "Penalized, skip\n");
            continue;
          }

          if(max_pipe_len) {
            if(pipeLen < best_pipe_len) {
              /* This connection has a shorter pipe so far. We'll pick this
                 and continue searching */
              chosen = check;
              best_pipe_len = pipeLen;
              continue;
            }
          }
          else {
            /* When not pipelining (== multiplexed), we have a match here! */
            chosen = check;
            infof(data, "Multiplexed connection found!\n");
            break;
          }
        }
        else {
          /* We have found a connection. Let's stop searching. */
          chosen = check;
          break;
        }
      }
    }
  }

  if(chosen) {
    /* mark it as used before releasing the lock */
    chosen->inuse = TRUE;
    Curl_conncache_unlock(needle);
    *usethis = chosen;
    return TRUE; /* yes, we found one to use! */
  }
  Curl_conncache_unlock(needle);

  if(foundPendingCandidate && data->set.pipewait) {
    infof(data,
          "Found pending candidate for reuse and CURLOPT_PIPEWAIT is set\n");
    *waitpipe = TRUE;
  }

  return FALSE; /* no matching connecting exists */
}

/* after a TCP connection to the proxy has been verified, this function does
   the next magic step.

   Note: this function's sub-functions call failf()

*/
CURLcode Curl_connected_proxy(struct connectdata *conn, int sockindex)
{
  CURLcode result = CURLE_OK;

  if(conn->bits.socksproxy) {
#ifndef CURL_DISABLE_PROXY
    /* for the secondary socket (FTP), use the "connect to host"
     * but ignore the "connect to port" (use the secondary port)
     */
    const char * const host = conn->bits.httpproxy ?
                              conn->http_proxy.host.name :
                              conn->bits.conn_to_host ?
                              conn->conn_to_host.name :
                              sockindex == SECONDARYSOCKET ?
                              conn->secondaryhostname : conn->host.name;
    const int port = conn->bits.httpproxy ? (int)conn->http_proxy.port :
                     sockindex == SECONDARYSOCKET ? conn->secondary_port :
                     conn->bits.conn_to_port ? conn->conn_to_port :
                     conn->remote_port;
    conn->bits.socksproxy_connecting = TRUE;
    switch(conn->socks_proxy.proxytype) {
    case CURLPROXY_SOCKS5:
    case CURLPROXY_SOCKS5_HOSTNAME:
      result = Curl_SOCKS5(conn->socks_proxy.user, conn->socks_proxy.passwd,
                         host, port, sockindex, conn);
      break;

    case CURLPROXY_SOCKS4:
    case CURLPROXY_SOCKS4A:
      result = Curl_SOCKS4(conn->socks_proxy.user, host, port, sockindex,
                           conn);
      break;

    default:
      failf(conn->data, "unknown proxytype option given");
      result = CURLE_COULDNT_CONNECT;
    } /* switch proxytype */
    conn->bits.socksproxy_connecting = FALSE;
#else
  (void)sockindex;
#endif /* CURL_DISABLE_PROXY */
  }

  return result;
}

/*
 * verboseconnect() displays verbose information after a connect
 */
#ifndef CURL_DISABLE_VERBOSE_STRINGS
void Curl_verboseconnect(struct connectdata *conn)
{
  if(conn->data->set.verbose)
    infof(conn->data, "Connected to %s (%s) port %ld (#%ld)\n",
          conn->bits.socksproxy ? conn->socks_proxy.host.dispname :
          conn->bits.httpproxy ? conn->http_proxy.host.dispname :
          conn->bits.conn_to_host ? conn->conn_to_host.dispname :
          conn->host.dispname,
          conn->ip_addr_str, conn->port, conn->connection_id);
}
#endif

int Curl_protocol_getsock(struct connectdata *conn,
                          curl_socket_t *socks,
                          int numsocks)
{
  if(conn->handler->proto_getsock)
    return conn->handler->proto_getsock(conn, socks, numsocks);
  return GETSOCK_BLANK;
}

int Curl_doing_getsock(struct connectdata *conn,
                       curl_socket_t *socks,
                       int numsocks)
{
  if(conn && conn->handler->doing_getsock)
    return conn->handler->doing_getsock(conn, socks, numsocks);
  return GETSOCK_BLANK;
}

/*
 * We are doing protocol-specific connecting and this is being called over and
 * over from the multi interface until the connection phase is done on
 * protocol layer.
 */

CURLcode Curl_protocol_connecting(struct connectdata *conn,
                                  bool *done)
{
  CURLcode result = CURLE_OK;

  if(conn && conn->handler->connecting) {
    *done = FALSE;
    result = conn->handler->connecting(conn, done);
  }
  else
    *done = TRUE;

  return result;
}

/*
 * We are DOING this is being called over and over from the multi interface
 * until the DOING phase is done on protocol layer.
 */

CURLcode Curl_protocol_doing(struct connectdata *conn, bool *done)
{
  CURLcode result = CURLE_OK;

  if(conn && conn->handler->doing) {
    *done = FALSE;
    result = conn->handler->doing(conn, done);
  }
  else
    *done = TRUE;

  return result;
}

/*
 * We have discovered that the TCP connection has been successful, we can now
 * proceed with some action.
 *
 */
CURLcode Curl_protocol_connect(struct connectdata *conn,
                               bool *protocol_done)
{
  CURLcode result = CURLE_OK;

  *protocol_done = FALSE;

  if(conn->bits.tcpconnect[FIRSTSOCKET] && conn->bits.protoconnstart) {
    /* We already are connected, get back. This may happen when the connect
       worked fine in the first call, like when we connect to a local server
       or proxy. Note that we don't know if the protocol is actually done.

       Unless this protocol doesn't have any protocol-connect callback, as
       then we know we're done. */
    if(!conn->handler->connecting)
      *protocol_done = TRUE;

    return CURLE_OK;
  }

  if(!conn->bits.protoconnstart) {

    result = Curl_proxy_connect(conn, FIRSTSOCKET);
    if(result)
      return result;

    if(CONNECT_FIRSTSOCKET_PROXY_SSL())
      /* wait for HTTPS proxy SSL initialization to complete */
      return CURLE_OK;

    if(conn->bits.tunnel_proxy && conn->bits.httpproxy &&
       Curl_connect_ongoing(conn))
      /* when using an HTTP tunnel proxy, await complete tunnel establishment
         before proceeding further. Return CURLE_OK so we'll be called again */
      return CURLE_OK;

    if(conn->handler->connect_it) {
      /* is there a protocol-specific connect() procedure? */

      /* Call the protocol-specific connect function */
      result = conn->handler->connect_it(conn, protocol_done);
    }
    else
      *protocol_done = TRUE;

    /* it has started, possibly even completed but that knowledge isn't stored
       in this bit! */
    if(!result)
      conn->bits.protoconnstart = TRUE;
  }

  return result; /* pass back status */
}

/*
 * Helpers for IDNA conversions.
 */
static bool is_ASCII_name(const char *hostname)
{
  const unsigned char *ch = (const unsigned char *)hostname;

  while(*ch) {
    if(*ch++ & 0x80)
      return FALSE;
  }
  return TRUE;
}

/*
 * Perform any necessary IDN conversion of hostname
 */
static CURLcode fix_hostname(struct connectdata *conn, struct hostname *host)
{
  size_t len;
  struct Curl_easy *data = conn->data;

#ifndef USE_LIBIDN2
  (void)data;
  (void)conn;
#elif defined(CURL_DISABLE_VERBOSE_STRINGS)
  (void)conn;
#endif

  /* set the name we use to display the host name */
  host->dispname = host->name;

  len = strlen(host->name);
  if(len && (host->name[len-1] == '.'))
    /* strip off a single trailing dot if present, primarily for SNI but
       there's no use for it */
    host->name[len-1] = 0;

  /* Check name for non-ASCII and convert hostname to ACE form if we can */
  if(!is_ASCII_name(host->name)) {
#ifdef USE_LIBIDN2
    if(idn2_check_version(IDN2_VERSION)) {
      char *ace_hostname = NULL;
#if IDN2_VERSION_NUMBER >= 0x00140000
      /* IDN2_NFC_INPUT: Normalize input string using normalization form C.
         IDN2_NONTRANSITIONAL: Perform Unicode TR46 non-transitional
         processing. */
      int flags = IDN2_NFC_INPUT | IDN2_NONTRANSITIONAL;
#else
      int flags = IDN2_NFC_INPUT;
#endif
      int rc = idn2_lookup_ul((const char *)host->name, &ace_hostname, flags);
      if(rc == IDN2_OK) {
        host->encalloc = (char *)ace_hostname;
        /* change the name pointer to point to the encoded hostname */
        host->name = host->encalloc;
      }
      else {
        failf(data, "Failed to convert %s to ACE; %s\n", host->name,
              idn2_strerror(rc));
        return CURLE_URL_MALFORMAT;
      }
    }
#elif defined(USE_WIN32_IDN)
    char *ace_hostname = NULL;

    if(curl_win32_idn_to_ascii(host->name, &ace_hostname)) {
      host->encalloc = ace_hostname;
      /* change the name pointer to point to the encoded hostname */
      host->name = host->encalloc;
    }
    else {
      failf(data, "Failed to convert %s to ACE;\n", host->name);
      return CURLE_URL_MALFORMAT;
    }
#else
    infof(data, "IDN support not present, can't parse Unicode domains\n");
#endif
  }
  {
    char *hostp;
    for(hostp = host->name; *hostp; hostp++) {
      if(*hostp <= 32) {
        failf(data, "Host name '%s' contains bad letter", host->name);
        return CURLE_URL_MALFORMAT;
      }
    }
  }
  return CURLE_OK;
}

/*
 * Frees data allocated by fix_hostname()
 */
static void free_fixed_hostname(struct hostname *host)
{
#if defined(USE_LIBIDN2)
  if(host->encalloc) {
    idn2_free(host->encalloc); /* must be freed with idn2_free() since this was
                                 allocated by libidn */
    host->encalloc = NULL;
  }
#elif defined(USE_WIN32_IDN)
  free(host->encalloc); /* must be freed with free() since this was
                           allocated by curl_win32_idn_to_ascii */
  host->encalloc = NULL;
#else
  (void)host;
#endif
}

static void llist_dtor(void *user, void *element)
{
  (void)user;
  (void)element;
  /* Do nothing */
}

/*
 * Allocate and initialize a new connectdata object.
 */
static struct connectdata *allocate_conn(struct Curl_easy *data)
{
  struct connectdata *conn = calloc(1, sizeof(struct connectdata));
  if(!conn)
    return NULL;

#ifdef USE_SSL
  /* The SSL backend-specific data (ssl_backend_data) objects are allocated as
     a separate array to ensure suitable alignment.
     Note that these backend pointers can be swapped by vtls (eg ssl backend
     data becomes proxy backend data). */
  {
    size_t sslsize = Curl_ssl->sizeof_ssl_backend_data;
    char *ssl = calloc(4, sslsize);
    if(!ssl) {
      free(conn);
      return NULL;
    }
    conn->ssl_extra = ssl;
    conn->ssl[0].backend = (void *)ssl;
    conn->ssl[1].backend = (void *)(ssl + sslsize);
    conn->proxy_ssl[0].backend = (void *)(ssl + 2 * sslsize);
    conn->proxy_ssl[1].backend = (void *)(ssl + 3 * sslsize);
  }
#endif

  conn->handler = &Curl_handler_dummy;  /* Be sure we have a handler defined
                                           already from start to avoid NULL
                                           situations and checks */

  /* and we setup a few fields in case we end up actually using this struct */

  conn->sock[FIRSTSOCKET] = CURL_SOCKET_BAD;     /* no file descriptor */
  conn->sock[SECONDARYSOCKET] = CURL_SOCKET_BAD; /* no file descriptor */
  conn->tempsock[0] = CURL_SOCKET_BAD; /* no file descriptor */
  conn->tempsock[1] = CURL_SOCKET_BAD; /* no file descriptor */
  conn->connection_id = -1;    /* no ID */
  conn->port = -1; /* unknown at this point */
  conn->remote_port = -1; /* unknown at this point */
#if defined(USE_RECV_BEFORE_SEND_WORKAROUND) && defined(DEBUGBUILD)
  conn->postponed[0].bindsock = CURL_SOCKET_BAD; /* no file descriptor */
  conn->postponed[1].bindsock = CURL_SOCKET_BAD; /* no file descriptor */
#endif /* USE_RECV_BEFORE_SEND_WORKAROUND && DEBUGBUILD */

  /* Default protocol-independent behavior doesn't support persistent
     connections, so we set this to force-close. Protocols that support
     this need to set this to FALSE in their "curl_do" functions. */
  connclose(conn, "Default to force-close");

  /* Store creation time to help future close decision making */
  conn->created = Curl_now();

  conn->data = data; /* Setup the association between this connection
                        and the Curl_easy */

  conn->http_proxy.proxytype = data->set.proxytype;
  conn->socks_proxy.proxytype = CURLPROXY_SOCKS4;

#ifdef CURL_DISABLE_PROXY

  conn->bits.proxy = FALSE;
  conn->bits.httpproxy = FALSE;
  conn->bits.socksproxy = FALSE;
  conn->bits.proxy_user_passwd = FALSE;
  conn->bits.tunnel_proxy = FALSE;

#else /* CURL_DISABLE_PROXY */

  /* note that these two proxy bits are now just on what looks to be
     requested, they may be altered down the road */
  conn->bits.proxy = (data->set.str[STRING_PROXY] &&
                      *data->set.str[STRING_PROXY]) ? TRUE : FALSE;
  conn->bits.httpproxy = (conn->bits.proxy &&
                          (conn->http_proxy.proxytype == CURLPROXY_HTTP ||
                           conn->http_proxy.proxytype == CURLPROXY_HTTP_1_0 ||
                           conn->http_proxy.proxytype == CURLPROXY_HTTPS)) ?
                           TRUE : FALSE;
  conn->bits.socksproxy = (conn->bits.proxy &&
                           !conn->bits.httpproxy) ? TRUE : FALSE;

  if(data->set.str[STRING_PRE_PROXY] && *data->set.str[STRING_PRE_PROXY]) {
    conn->bits.proxy = TRUE;
    conn->bits.socksproxy = TRUE;
  }

  conn->bits.proxy_user_passwd =
    (data->set.str[STRING_PROXYUSERNAME]) ? TRUE : FALSE;
  conn->bits.tunnel_proxy = data->set.tunnel_thru_httpproxy;

#endif /* CURL_DISABLE_PROXY */

  conn->bits.user_passwd = (data->set.str[STRING_USERNAME]) ? TRUE : FALSE;
  conn->bits.ftp_use_epsv = data->set.ftp_use_epsv;
  conn->bits.ftp_use_eprt = data->set.ftp_use_eprt;

  conn->ssl_config.verifystatus = data->set.ssl.primary.verifystatus;
  conn->ssl_config.verifypeer = data->set.ssl.primary.verifypeer;
  conn->ssl_config.verifyhost = data->set.ssl.primary.verifyhost;
  conn->proxy_ssl_config.verifystatus =
    data->set.proxy_ssl.primary.verifystatus;
  conn->proxy_ssl_config.verifypeer = data->set.proxy_ssl.primary.verifypeer;
  conn->proxy_ssl_config.verifyhost = data->set.proxy_ssl.primary.verifyhost;

  conn->ip_version = data->set.ipver;

#if !defined(CURL_DISABLE_HTTP) && defined(USE_NTLM) && \
    defined(NTLM_WB_ENABLED)
  conn->ntlm_auth_hlpr_socket = CURL_SOCKET_BAD;
  conn->ntlm_auth_hlpr_pid = 0;
  conn->challenge_header = NULL;
  conn->response_header = NULL;
#endif

  if(Curl_pipeline_wanted(data->multi, CURLPIPE_HTTP1) &&
     !conn->master_buffer) {
    /* Allocate master_buffer to be used for HTTP/1 pipelining */
    conn->master_buffer = calloc(MASTERBUF_SIZE, sizeof(char));
    if(!conn->master_buffer)
      goto error;
  }

  /* Initialize the pipeline lists */
  Curl_llist_init(&conn->send_pipe, (curl_llist_dtor) llist_dtor);
  Curl_llist_init(&conn->recv_pipe, (curl_llist_dtor) llist_dtor);

#ifdef HAVE_GSSAPI
  conn->data_prot = PROT_CLEAR;
#endif

  /* Store the local bind parameters that will be used for this connection */
  if(data->set.str[STRING_DEVICE]) {
    conn->localdev = strdup(data->set.str[STRING_DEVICE]);
    if(!conn->localdev)
      goto error;
  }
  conn->localportrange = data->set.localportrange;
  conn->localport = data->set.localport;

  /* the close socket stuff needs to be copied to the connection struct as
     it may live on without (this specific) Curl_easy */
  conn->fclosesocket = data->set.fclosesocket;
  conn->closesocket_client = data->set.closesocket_client;

  return conn;
  error:

  Curl_llist_destroy(&conn->send_pipe, NULL);
  Curl_llist_destroy(&conn->recv_pipe, NULL);

  free(conn->master_buffer);
  free(conn->localdev);
#ifdef USE_SSL
  free(conn->ssl_extra);
#endif
  free(conn);
  return NULL;
}

static CURLcode findprotocol(struct Curl_easy *data,
                             struct connectdata *conn,
                             const char *protostr)
{
  const struct Curl_handler * const *pp;
  const struct Curl_handler *p;

  /* Scan protocol handler table and match against 'protostr' to set a few
     variables based on the URL. Now that the handler may be changed later
     when the protocol specific setup function is called. */
  for(pp = protocols; (p = *pp) != NULL; pp++) {
    if(strcasecompare(p->scheme, protostr)) {
      /* Protocol found in table. Check if allowed */
      if(!(data->set.allowed_protocols & p->protocol))
        /* nope, get out */
        break;

      /* it is allowed for "normal" request, now do an extra check if this is
         the result of a redirect */
      if(data->state.this_is_a_follow &&
         !(data->set.redir_protocols & p->protocol))
        /* nope, get out */
        break;

      /* Perform setup complement if some. */
      conn->handler = conn->given = p;

      /* 'port' and 'remote_port' are set in setup_connection_internals() */
      return CURLE_OK;
    }
  }


  /* The protocol was not found in the table, but we don't have to assign it
     to anything since it is already assigned to a dummy-struct in the
     create_conn() function when the connectdata struct is allocated. */
  failf(data, "Protocol \"%s\" not supported or disabled in " LIBCURL_NAME,
        protostr);

  return CURLE_UNSUPPORTED_PROTOCOL;
}

/*
 * Parse URL and fill in the relevant members of the connection struct.
 */
static CURLcode parseurlandfillconn(struct Curl_easy *data,
                                    struct connectdata *conn,
                                    bool *prot_missing,
                                    char **userp, char **passwdp,
                                    char **optionsp)
{
  char *at;
  char *fragment;
  char *path = data->state.path;
  char *query;
  int i;
  int rc;
  const char *protop = "";
  CURLcode result;
  bool rebuild_url = FALSE;
  bool url_has_scheme = FALSE;
  char protobuf[16];

  *prot_missing = FALSE;

  /* We might pass the entire URL into the request so we need to make sure
   * there are no bad characters in there.*/
  if(strpbrk(data->change.url, "\r\n")) {
    failf(data, "Illegal characters found in URL");
    return CURLE_URL_MALFORMAT;
  }

  /*************************************************************
   * Parse the URL.
   *
   * We need to parse the url even when using the proxy, because we will need
   * the hostname and port in case we are trying to SSL connect through the
   * proxy -- and we don't know if we will need to use SSL until we parse the
   * url ...
   ************************************************************/
  if(data->change.url[0] == ':') {
    failf(data, "Bad URL, colon is first character");
    return CURLE_URL_MALFORMAT;
  }

  /* MSDOS/Windows style drive prefix, eg c: in c:foo */
#define STARTS_WITH_DRIVE_PREFIX(str) \
  ((('a' <= str[0] && str[0] <= 'z') || \
    ('A' <= str[0] && str[0] <= 'Z')) && \
   (str[1] == ':'))

  /* MSDOS/Windows style drive prefix, optionally with
   * a '|' instead of ':', followed by a slash or NUL */
#define STARTS_WITH_URL_DRIVE_PREFIX(str) \
  ((('a' <= (str)[0] && (str)[0] <= 'z') || \
    ('A' <= (str)[0] && (str)[0] <= 'Z')) && \
   ((str)[1] == ':' || (str)[1] == '|') && \
   ((str)[2] == '/' || (str)[2] == '\\' || (str)[2] == 0))

  /* Don't mistake a drive letter for a scheme if the default protocol is file.
     curld --proto-default file c:/foo/bar.txt */
  if(STARTS_WITH_DRIVE_PREFIX(data->change.url) &&
     data->set.str[STRING_DEFAULT_PROTOCOL] &&
     strcasecompare(data->set.str[STRING_DEFAULT_PROTOCOL], "file")) {
    ; /* do nothing */
  }
  else { /* check for a scheme */
    for(i = 0; i < 16 && data->change.url[i]; ++i) {
      if(data->change.url[i] == '/')
        break;
      if(data->change.url[i] == ':') {
        url_has_scheme = TRUE;
        break;
      }
    }
  }

  /* handle the file: scheme */
  if((url_has_scheme && strncasecompare(data->change.url, "file:", 5)) ||
     (!url_has_scheme && data->set.str[STRING_DEFAULT_PROTOCOL] &&
      strcasecompare(data->set.str[STRING_DEFAULT_PROTOCOL], "file"))) {
    if(url_has_scheme)
      rc = sscanf(data->change.url, "%*15[^\n/:]:%[^\n]", path);
    else
      rc = sscanf(data->change.url, "%[^\n]", path);

    if(rc != 1) {
      failf(data, "Bad URL");
      return CURLE_URL_MALFORMAT;
    }

    if(url_has_scheme && path[0] == '/' && path[1] == '/' &&
       path[2] == '/' && path[3] == '/') {
      /* This appears to be a UNC string (usually indicating a SMB share).
       * We don't do SMB in file: URLs. (TODO?)
       */
      failf(data, "SMB shares are not supported in file: URLs.");
      return CURLE_URL_MALFORMAT;
    }

    /* Extra handling URLs with an authority component (i.e. that start with
     * "file://")
     *
     * We allow omitted hostname (e.g. file:/<path>) -- valid according to
     * RFC 8089, but not the (current) WHAT-WG URL spec.
     */
    if(url_has_scheme && path[0] == '/' && path[1] == '/') {
      /* swallow the two slashes */
      char *ptr = &path[2];

      /*
       * According to RFC 8089, a file: URL can be reliably dereferenced if:
       *
       *  o it has no/blank hostname, or
       *
       *  o the hostname matches "localhost" (case-insensitively), or
       *
       *  o the hostname is a FQDN that resolves to this machine.
       *
       * For brevity, we only consider URLs with empty, "localhost", or
       * "127.0.0.1" hostnames as local.
       *
       * Additionally, there is an exception for URLs with a Windows drive
       * letter in the authority (which was accidentally omitted from RFC 8089
       * Appendix E, but believe me, it was meant to be there. --MK)
       */
      if(ptr[0] != '/' && !STARTS_WITH_URL_DRIVE_PREFIX(ptr)) {
        /* the URL includes a host name, it must match "localhost" or
           "127.0.0.1" to be valid */
        if(!checkprefix("localhost/", ptr) &&
           !checkprefix("127.0.0.1/", ptr)) {
          failf(data, "Invalid file://hostname/, "
                      "expected localhost or 127.0.0.1 or none");
          return CURLE_URL_MALFORMAT;
        }
        ptr += 9; /* now points to the slash after the host */
      }

      /*
       * RFC 8089, Appendix D, Section D.1, says:
       *
       * > In a POSIX file system, the root of the file system is represented
       * > as a directory with a zero-length name, usually written as "/"; the
       * > presence of this root in a file URI can be taken as given by the
       * > initial slash in the "path-absolute" rule.
       *
       * i.e. the first slash is part of the path.
       *
       * However in RFC 1738 the "/" between the host (or port) and the
       * URL-path was NOT part of the URL-path.  Any agent that followed the
       * older spec strictly, and wanted to refer to a file with an absolute
       * path, would have included a second slash.  So if there are two
       * slashes, swallow one.
       */
      if('/' == ptr[1]) /* note: the only way ptr[0]!='/' is if ptr[1]==':' */
        ptr++;

      /* This cannot be done with strcpy, as the memory chunks overlap! */
      memmove(path, ptr, strlen(ptr) + 1);
    }

#if !defined(MSDOS) && !defined(WIN32) && !defined(__CYGWIN__)
    /* Don't allow Windows drive letters when not in Windows.
     * This catches both "file:/c:" and "file:c:" */
    if(('/' == path[0] && STARTS_WITH_URL_DRIVE_PREFIX(&path[1])) ||
       STARTS_WITH_URL_DRIVE_PREFIX(path)) {
      failf(data, "File drive letters are only accepted in MSDOS/Windows.");
      return CURLE_URL_MALFORMAT;
    }
#else
    /* If the path starts with a slash and a drive letter, ditch the slash */
    if('/' == path[0] && STARTS_WITH_URL_DRIVE_PREFIX(&path[1])) {
      /* This cannot be done with strcpy, as the memory chunks overlap! */
      memmove(path, &path[1], strlen(&path[1]) + 1);
    }
#endif

    protop = "file"; /* protocol string */
    *prot_missing = !url_has_scheme;
  }
  else {
    /* clear path */
    char slashbuf[4];
    path[0] = 0;

    rc = sscanf(data->change.url,
                "%15[^\n/:]:%3[/]%[^\n/?#]%[^\n]",
                protobuf, slashbuf, conn->host.name, path);
    if(2 == rc) {
      failf(data, "Bad URL");
      return CURLE_URL_MALFORMAT;
    }
    if(3 > rc) {

      /*
       * The URL was badly formatted, let's try the browser-style _without_
       * protocol specified like 'http://'.
       */
      rc = sscanf(data->change.url, "%[^\n/?#]%[^\n]", conn->host.name, path);
      if(1 > rc) {
        /*
         * We couldn't even get this format.
         * djgpp 2.04 has a sscanf() bug where 'conn->host.name' is
         * assigned, but the return value is EOF!
         */
#if defined(__DJGPP__) && (DJGPP_MINOR == 4)
        if(!(rc == -1 && *conn->host.name))
#endif
        {
          failf(data, "<url> malformed");
          return CURLE_URL_MALFORMAT;
        }
      }

      /*
       * Since there was no protocol part specified in the URL use the
       * user-specified default protocol. If we weren't given a default make a
       * guess by matching some protocols against the host's outermost
       * sub-domain name. Finally if there was no match use HTTP.
       */

      protop = data->set.str[STRING_DEFAULT_PROTOCOL];
      if(!protop) {
        /* Note: if you add a new protocol, please update the list in
         * lib/version.c too! */
        if(checkprefix("FTP.", conn->host.name))
          protop = "ftp";
        else if(checkprefix("DICT.", conn->host.name))
          protop = "DICT";
        else if(checkprefix("LDAP.", conn->host.name))
          protop = "LDAP";
        else if(checkprefix("IMAP.", conn->host.name))
          protop = "IMAP";
        else if(checkprefix("SMTP.", conn->host.name))
          protop = "smtp";
        else if(checkprefix("POP3.", conn->host.name))
          protop = "pop3";
        else
          protop = "http";
      }

      *prot_missing = TRUE; /* not given in URL */
    }
    else {
      size_t s = strlen(slashbuf);
      protop = protobuf;
      if(s != 2) {
        infof(data, "Unwillingly accepted illegal URL using %d slash%s!\n",
              s, s>1?"es":"");

        if(data->change.url_alloc)
          free(data->change.url);
        /* repair the URL to use two slashes */
        data->change.url = aprintf("%s://%s%s",
                                   protobuf, conn->host.name, path);
        if(!data->change.url)
          return CURLE_OUT_OF_MEMORY;
        data->change.url_alloc = TRUE;
      }
    }
  }

  /* We search for '?' in the host name (but only on the right side of a
   * @-letter to allow ?-letters in username and password) to handle things
   * like http://example.com?param= (notice the missing '/').
   */
  at = strchr(conn->host.name, '@');
  if(at)
    query = strchr(at + 1, '?');
  else
    query = strchr(conn->host.name, '?');

  if(query) {
    /* We must insert a slash before the '?'-letter in the URL. If the URL had
       a slash after the '?', that is where the path currently begins and the
       '?string' is still part of the host name.

       We must move the trailing part from the host name and put it first in
       the path. And have it all prefixed with a slash.
    */

    size_t hostlen = strlen(query);
    size_t pathlen = strlen(path);

    /* move the existing path plus the zero byte forward, to make room for
       the host-name part */
    memmove(path + hostlen + 1, path, pathlen + 1);

     /* now copy the trailing host part in front of the existing path */
    memcpy(path + 1, query, hostlen);

    path[0]='/'; /* prepend the missing slash */
    rebuild_url = TRUE;

    *query = 0; /* now cut off the hostname at the ? */
  }
  else if(!path[0]) {
    /* if there's no path set, use a single slash */
    strcpy(path, "/");
    rebuild_url = TRUE;
  }

  /* If the URL is malformatted (missing a '/' after hostname before path) we
   * insert a slash here. The only letters except '/' that can start a path is
   * '?' and '#' - as controlled by the two sscanf() patterns above.
   */
  if(path[0] != '/') {
    /* We need this function to deal with overlapping memory areas. We know
       that the memory area 'path' points to is 'urllen' bytes big and that
       is bigger than the path. Use +1 to move the zero byte too. */
    memmove(&path[1], path, strlen(path) + 1);
    path[0] = '/';
    rebuild_url = TRUE;
  }
  else if(!data->set.path_as_is) {
    /* sanitise paths and remove ../ and ./ sequences according to RFC3986 */
    char *newp = Curl_dedotdotify(path);
    if(!newp)
      return CURLE_OUT_OF_MEMORY;

    if(strcmp(newp, path)) {
      rebuild_url = TRUE;
      free(data->state.pathbuffer);
      data->state.pathbuffer = newp;
      data->state.path = newp;
      path = newp;
    }
    else
      free(newp);
  }

  /*
   * "rebuild_url" means that one or more URL components have been modified so
   * we need to generate an updated full version.  We need the corrected URL
   * when communicating over HTTP proxy and we don't know at this point if
   * we're using a proxy or not.
   */
  if(rebuild_url) {
    char *reurl;

    size_t plen = strlen(path); /* new path, should be 1 byte longer than
                                   the original */
    size_t prefixlen = strlen(conn->host.name);

    if(!*prot_missing) {
      size_t protolen = strlen(protop);

      if(curl_strnequal(protop, data->change.url, protolen))
        prefixlen += protolen;
      else {
        failf(data, "<url> malformed");
        return CURLE_URL_MALFORMAT;
      }

      if(curl_strnequal("://", &data->change.url[protolen], 3))
        prefixlen += 3;
      /* only file: is allowed to omit one or both slashes */
      else if(curl_strnequal("file:", data->change.url, 5))
        prefixlen += 1 + (data->change.url[5] == '/');
      else {
        failf(data, "<url> malformed");
        return CURLE_URL_MALFORMAT;
      }
    }

    reurl = malloc(prefixlen + plen + 1);
    if(!reurl)
      return CURLE_OUT_OF_MEMORY;

    /* copy the prefix */
    memcpy(reurl, data->change.url, prefixlen);

    /* append the trailing piece + zerobyte */
    memcpy(&reurl[prefixlen], path, plen + 1);

    /* possible free the old one */
    if(data->change.url_alloc) {
      Curl_safefree(data->change.url);
      data->change.url_alloc = FALSE;
    }

    infof(data, "Rebuilt URL to: %s\n", reurl);

    data->change.url = reurl;
    data->change.url_alloc = TRUE; /* free this later */
  }

  result = findprotocol(data, conn, protop);
  if(result)
    return result;

  /*
   * Parse the login details from the URL and strip them out of
   * the host name
   */
  result = parse_url_login(data, conn, userp, passwdp, optionsp);
  if(result)
    return result;

  if(conn->host.name[0] == '[') {
    /* This looks like an IPv6 address literal.  See if there is an address
       scope if there is no location header */
    char *percent = strchr(conn->host.name, '%');
    if(percent) {
      unsigned int identifier_offset = 3;
      char *endp;
      unsigned long scope;
      if(strncmp("%25", percent, 3) != 0) {
        infof(data,
              "Please URL encode %% as %%25, see RFC 6874.\n");
        identifier_offset = 1;
      }
      scope = strtoul(percent + identifier_offset, &endp, 10);
      if(*endp == ']') {
        /* The address scope was well formed.  Knock it out of the
           hostname. */
        memmove(percent, endp, strlen(endp) + 1);
        conn->scope_id = (unsigned int)scope;
      }
      else {
        /* Zone identifier is not numeric */
#if defined(HAVE_NET_IF_H) && defined(IFNAMSIZ) && defined(HAVE_IF_NAMETOINDEX)
        char ifname[IFNAMSIZ + 2];
        char *square_bracket;
        unsigned int scopeidx = 0;
        strncpy(ifname, percent + identifier_offset, IFNAMSIZ + 2);
        /* Ensure nullbyte termination */
        ifname[IFNAMSIZ + 1] = '\0';
        square_bracket = strchr(ifname, ']');
        if(square_bracket) {
          /* Remove ']' */
          *square_bracket = '\0';
          scopeidx = if_nametoindex(ifname);
          if(scopeidx == 0) {
            infof(data, "Invalid network interface: %s; %s\n", ifname,
                  strerror(errno));
          }
        }
        if(scopeidx > 0) {
          char *p = percent + identifier_offset + strlen(ifname);

          /* Remove zone identifier from hostname */
          memmove(percent, p, strlen(p) + 1);
          conn->scope_id = scopeidx;
        }
        else
#endif /* HAVE_NET_IF_H && IFNAMSIZ */
          infof(data, "Invalid IPv6 address format\n");
      }
    }
  }

  if(data->set.scope_id)
    /* Override any scope that was set above.  */
    conn->scope_id = data->set.scope_id;

  /* Remove the fragment part of the path. Per RFC 2396, this is always the
     last part of the URI. We are looking for the first '#' so that we deal
     gracefully with non conformant URI such as http://example.com#foo#bar. */
  fragment = strchr(path, '#');
  if(fragment) {
    *fragment = 0;

    /* we know the path part ended with a fragment, so we know the full URL
       string does too and we need to cut it off from there so it isn't used
       over proxy */
    fragment = strchr(data->change.url, '#');
    if(fragment)
      *fragment = 0;
  }

  /*
   * So if the URL was A://B/C#D,
   *   protop is A
   *   conn->host.name is B
   *   data->state.path is /C
   */
  return CURLE_OK;
}

/*
 * If we're doing a resumed transfer, we need to setup our stuff
 * properly.
 */
static CURLcode setup_range(struct Curl_easy *data)
{
  struct UrlState *s = &data->state;
  s->resume_from = data->set.set_resume_from;
  if(s->resume_from || data->set.str[STRING_SET_RANGE]) {
    if(s->rangestringalloc)
      free(s->range);

    if(s->resume_from)
      s->range = aprintf("%" CURL_FORMAT_CURL_OFF_TU "-", s->resume_from);
    else
      s->range = strdup(data->set.str[STRING_SET_RANGE]);

    s->rangestringalloc = (s->range) ? TRUE : FALSE;

    if(!s->range)
      return CURLE_OUT_OF_MEMORY;

    /* tell ourselves to fetch this range */
    s->use_range = TRUE;        /* enable range download */
  }
  else
    s->use_range = FALSE; /* disable range download */

  return CURLE_OK;
}


/*
 * setup_connection_internals() -
 *
 * Setup connection internals specific to the requested protocol in the
 * Curl_easy. This is inited and setup before the connection is made but
 * is about the particular protocol that is to be used.
 *
 * This MUST get called after proxy magic has been figured out.
 */
static CURLcode setup_connection_internals(struct connectdata *conn)
{
  const struct Curl_handler * p;
  CURLcode result;
  struct Curl_easy *data = conn->data;

  /* in some case in the multi state-machine, we go back to the CONNECT state
     and then a second (or third or...) call to this function will be made
     without doing a DISCONNECT or DONE in between (since the connection is
     yet in place) and therefore this function needs to first make sure
     there's no lingering previous data allocated. */
  Curl_free_request_state(data);

  memset(&data->req, 0, sizeof(struct SingleRequest));
  data->req.maxdownload = -1;

  conn->socktype = SOCK_STREAM; /* most of them are TCP streams */

  /* Perform setup complement if some. */
  p = conn->handler;

  if(p->setup_connection) {
    result = (*p->setup_connection)(conn);

    if(result)
      return result;

    p = conn->handler;              /* May have changed. */
  }

  if(conn->port < 0)
    /* we check for -1 here since if proxy was detected already, this
       was very likely already set to the proxy port */
    conn->port = p->defport;

  return CURLE_OK;
}

/*
 * Curl_free_request_state() should free temp data that was allocated in the
 * Curl_easy for this single request.
 */

void Curl_free_request_state(struct Curl_easy *data)
{
  Curl_safefree(data->req.protop);
  Curl_safefree(data->req.newurl);
}


#ifndef CURL_DISABLE_PROXY
/****************************************************************
* Checks if the host is in the noproxy list. returns true if it matches
* and therefore the proxy should NOT be used.
****************************************************************/
static bool check_noproxy(const char *name, const char *no_proxy)
{
  /* no_proxy=domain1.dom,host.domain2.dom
   *   (a comma-separated list of hosts which should
   *   not be proxied, or an asterisk to override
   *   all proxy variables)
   */
  size_t tok_start;
  size_t tok_end;
  const char *separator = ", ";
  size_t no_proxy_len;
  size_t namelen;
  char *endptr;

  if(no_proxy && no_proxy[0]) {
    if(strcasecompare("*", no_proxy)) {
      return TRUE;
    }

    /* NO_PROXY was specified and it wasn't just an asterisk */

    no_proxy_len = strlen(no_proxy);
    endptr = strchr(name, ':');
    if(endptr)
      namelen = endptr - name;
    else
      namelen = strlen(name);

    for(tok_start = 0; tok_start < no_proxy_len; tok_start = tok_end + 1) {
      while(tok_start < no_proxy_len &&
            strchr(separator, no_proxy[tok_start]) != NULL) {
        /* Look for the beginning of the token. */
        ++tok_start;
      }

      if(tok_start == no_proxy_len)
        break; /* It was all trailing separator chars, no more tokens. */

      for(tok_end = tok_start; tok_end < no_proxy_len &&
            strchr(separator, no_proxy[tok_end]) == NULL; ++tok_end)
        /* Look for the end of the token. */
        ;

      /* To match previous behaviour, where it was necessary to specify
       * ".local.com" to prevent matching "notlocal.com", we will leave
       * the '.' off.
       */
      if(no_proxy[tok_start] == '.')
        ++tok_start;

      if((tok_end - tok_start) <= namelen) {
        /* Match the last part of the name to the domain we are checking. */
        const char *checkn = name + namelen - (tok_end - tok_start);
        if(strncasecompare(no_proxy + tok_start, checkn,
                           tok_end - tok_start)) {
          if((tok_end - tok_start) == namelen || *(checkn - 1) == '.') {
            /* We either have an exact match, or the previous character is a .
             * so it is within the same domain, so no proxy for this host.
             */
            return TRUE;
          }
        }
      } /* if((tok_end - tok_start) <= namelen) */
    } /* for(tok_start = 0; tok_start < no_proxy_len;
         tok_start = tok_end + 1) */
  } /* NO_PROXY was specified and it wasn't just an asterisk */

  return FALSE;
}

#ifndef CURL_DISABLE_HTTP
/****************************************************************
* Detect what (if any) proxy to use. Remember that this selects a host
* name and is not limited to HTTP proxies only.
* The returned pointer must be freed by the caller (unless NULL)
****************************************************************/
static char *detect_proxy(struct connectdata *conn)
{
  char *proxy = NULL;

  /* If proxy was not specified, we check for default proxy environment
   * variables, to enable i.e Lynx compliance:
   *
   * http_proxy=http://some.server.dom:port/
   * https_proxy=http://some.server.dom:port/
   * ftp_proxy=http://some.server.dom:port/
   * no_proxy=domain1.dom,host.domain2.dom
   *   (a comma-separated list of hosts which should
   *   not be proxied, or an asterisk to override
   *   all proxy variables)
   * all_proxy=http://some.server.dom:port/
   *   (seems to exist for the CERN www lib. Probably
   *   the first to check for.)
   *
   * For compatibility, the all-uppercase versions of these variables are
   * checked if the lowercase versions don't exist.
   */
  char proxy_env[128];
  const char *protop = conn->handler->scheme;
  char *envp = proxy_env;
  char *prox;

  /* Now, build <protocol>_proxy and check for such a one to use */
  while(*protop)
    *envp++ = (char)tolower((int)*protop++);

  /* append _proxy */
  strcpy(envp, "_proxy");

  /* read the protocol proxy: */
  prox = curl_getenv(proxy_env);

  /*
   * We don't try the uppercase version of HTTP_PROXY because of
   * security reasons:
   *
   * When curl is used in a webserver application
   * environment (cgi or php), this environment variable can
   * be controlled by the web server user by setting the
   * http header 'Proxy:' to some value.
   *
   * This can cause 'internal' http/ftp requests to be
   * arbitrarily redirected by any external attacker.
   */
  if(!prox && !strcasecompare("http_proxy", proxy_env)) {
    /* There was no lowercase variable, try the uppercase version: */
    Curl_strntoupper(proxy_env, proxy_env, sizeof(proxy_env));
    prox = curl_getenv(proxy_env);
  }

  if(prox)
    proxy = prox; /* use this */
  else {
    proxy = curl_getenv("all_proxy"); /* default proxy to use */
    if(!proxy)
      proxy = curl_getenv("ALL_PROXY");
  }

  return proxy;
}
#endif /* CURL_DISABLE_HTTP */

/*
 * If this is supposed to use a proxy, we need to figure out the proxy
 * host name, so that we can re-use an existing connection
 * that may exist registered to the same proxy host.
 */
static CURLcode parse_proxy(struct Curl_easy *data,
                            struct connectdata *conn, char *proxy,
                            curl_proxytype proxytype)
{
  char *prox_portno;
  char *endofprot;

  /* We use 'proxyptr' to point to the proxy name from now on... */
  char *proxyptr;
  char *portptr;
  char *atsign;
  long port = -1;
  char *proxyuser = NULL;
  char *proxypasswd = NULL;
  bool sockstype;

  /* We do the proxy host string parsing here. We want the host name and the
   * port name. Accept a protocol:// prefix
   */

  /* Parse the protocol part if present */
  endofprot = strstr(proxy, "://");
  if(endofprot) {
    proxyptr = endofprot + 3;
    if(checkprefix("https", proxy))
      proxytype = CURLPROXY_HTTPS;
    else if(checkprefix("socks5h", proxy))
      proxytype = CURLPROXY_SOCKS5_HOSTNAME;
    else if(checkprefix("socks5", proxy))
      proxytype = CURLPROXY_SOCKS5;
    else if(checkprefix("socks4a", proxy))
      proxytype = CURLPROXY_SOCKS4A;
    else if(checkprefix("socks4", proxy) || checkprefix("socks", proxy))
      proxytype = CURLPROXY_SOCKS4;
    else if(checkprefix("http:", proxy))
      ; /* leave it as HTTP or HTTP/1.0 */
    else {
      /* Any other xxx:// reject! */
      failf(data, "Unsupported proxy scheme for \'%s\'", proxy);
      return CURLE_COULDNT_CONNECT;
    }
  }
  else
    proxyptr = proxy; /* No xxx:// head: It's a HTTP proxy */

#ifdef USE_SSL
  if(!Curl_ssl->support_https_proxy)
#endif
    if(proxytype == CURLPROXY_HTTPS) {
      failf(data, "Unsupported proxy \'%s\', libcurl is built without the "
                  "HTTPS-proxy support.", proxy);
      return CURLE_NOT_BUILT_IN;
    }

  sockstype = proxytype == CURLPROXY_SOCKS5_HOSTNAME ||
              proxytype == CURLPROXY_SOCKS5 ||
              proxytype == CURLPROXY_SOCKS4A ||
              proxytype == CURLPROXY_SOCKS4;

  /* Is there a username and password given in this proxy url? */
  atsign = strchr(proxyptr, '@');
  if(atsign) {
    CURLcode result =
      Curl_parse_login_details(proxyptr, atsign - proxyptr,
                               &proxyuser, &proxypasswd, NULL);
    if(result)
      return result;
    proxyptr = atsign + 1;
  }

  /* start scanning for port number at this point */
  portptr = proxyptr;

  /* detect and extract RFC6874-style IPv6-addresses */
  if(*proxyptr == '[') {
    char *ptr = ++proxyptr; /* advance beyond the initial bracket */
    while(*ptr && (ISXDIGIT(*ptr) || (*ptr == ':') || (*ptr == '.')))
      ptr++;
    if(*ptr == '%') {
      /* There might be a zone identifier */
      if(strncmp("%25", ptr, 3))
        infof(data, "Please URL encode %% as %%25, see RFC 6874.\n");
      ptr++;
      /* Allow unreserved characters as defined in RFC 3986 */
      while(*ptr && (ISALPHA(*ptr) || ISXDIGIT(*ptr) || (*ptr == '-') ||
                     (*ptr == '.') || (*ptr == '_') || (*ptr == '~')))
        ptr++;
    }
    if(*ptr == ']')
      /* yeps, it ended nicely with a bracket as well */
      *ptr++ = 0;
    else
      infof(data, "Invalid IPv6 address format\n");
    portptr = ptr;
    /* Note that if this didn't end with a bracket, we still advanced the
     * proxyptr first, but I can't see anything wrong with that as no host
     * name nor a numeric can legally start with a bracket.
     */
  }

  /* Get port number off proxy.server.com:1080 */
  prox_portno = strchr(portptr, ':');
  if(prox_portno) {
    char *endp = NULL;

    *prox_portno = 0x0; /* cut off number from host name */
    prox_portno ++;
    /* now set the local port number */
    port = strtol(prox_portno, &endp, 10);
    if((endp && *endp && (*endp != '/') && (*endp != ' ')) ||
       (port < 0) || (port > 65535)) {
      /* meant to detect for example invalid IPv6 numerical addresses without
         brackets: "2a00:fac0:a000::7:13". Accept a trailing slash only
         because we then allow "URL style" with the number followed by a
         slash, used in curl test cases already. Space is also an acceptable
         terminating symbol. */
      infof(data, "No valid port number in proxy string (%s)\n",
            prox_portno);
    }
    else
      conn->port = port;
  }
  else {
    if(proxyptr[0]=='/') {
      /* If the first character in the proxy string is a slash, fail
         immediately. The following code will otherwise clear the string which
         will lead to code running as if no proxy was set! */
      Curl_safefree(proxyuser);
      Curl_safefree(proxypasswd);
      return CURLE_COULDNT_RESOLVE_PROXY;
    }

    /* without a port number after the host name, some people seem to use
       a slash so we strip everything from the first slash */
    atsign = strchr(proxyptr, '/');
    if(atsign)
      *atsign = '\0'; /* cut off path part from host name */

    if(data->set.proxyport)
      /* None given in the proxy string, then get the default one if it is
         given */
      port = data->set.proxyport;
    else {
      if(proxytype == CURLPROXY_HTTPS)
        port = CURL_DEFAULT_HTTPS_PROXY_PORT;
      else
        port = CURL_DEFAULT_PROXY_PORT;
    }
  }

  if(*proxyptr) {
    struct proxy_info *proxyinfo =
      sockstype ? &conn->socks_proxy : &conn->http_proxy;
    proxyinfo->proxytype = proxytype;

    if(proxyuser) {
      /* found user and password, rip them out.  note that we are unescaping
         them, as there is otherwise no way to have a username or password
         with reserved characters like ':' in them. */
      Curl_safefree(proxyinfo->user);
      proxyinfo->user = curl_easy_unescape(data, proxyuser, 0, NULL);
      Curl_safefree(proxyuser);

      if(!proxyinfo->user) {
        Curl_safefree(proxypasswd);
        return CURLE_OUT_OF_MEMORY;
      }

      Curl_safefree(proxyinfo->passwd);
      if(proxypasswd && strlen(proxypasswd) < MAX_CURL_PASSWORD_LENGTH)
        proxyinfo->passwd = curl_easy_unescape(data, proxypasswd, 0, NULL);
      else
        proxyinfo->passwd = strdup("");
      Curl_safefree(proxypasswd);

      if(!proxyinfo->passwd)
        return CURLE_OUT_OF_MEMORY;

      conn->bits.proxy_user_passwd = TRUE; /* enable it */
    }

    if(port >= 0) {
      proxyinfo->port = port;
      if(conn->port < 0 || sockstype || !conn->socks_proxy.host.rawalloc)
        conn->port = port;
    }

    /* now, clone the cleaned proxy host name */
    Curl_safefree(proxyinfo->host.rawalloc);
    proxyinfo->host.rawalloc = strdup(proxyptr);
    proxyinfo->host.name = proxyinfo->host.rawalloc;

    if(!proxyinfo->host.rawalloc)
      return CURLE_OUT_OF_MEMORY;
  }

  Curl_safefree(proxyuser);
  Curl_safefree(proxypasswd);

  return CURLE_OK;
}

/*
 * Extract the user and password from the authentication string
 */
static CURLcode parse_proxy_auth(struct Curl_easy *data,
                                 struct connectdata *conn)
{
  char proxyuser[MAX_CURL_USER_LENGTH]="";
  char proxypasswd[MAX_CURL_PASSWORD_LENGTH]="";
  CURLcode result;

  if(data->set.str[STRING_PROXYUSERNAME] != NULL) {
    strncpy(proxyuser, data->set.str[STRING_PROXYUSERNAME],
            MAX_CURL_USER_LENGTH);
    proxyuser[MAX_CURL_USER_LENGTH-1] = '\0';   /*To be on safe side*/
  }
  if(data->set.str[STRING_PROXYPASSWORD] != NULL) {
    strncpy(proxypasswd, data->set.str[STRING_PROXYPASSWORD],
            MAX_CURL_PASSWORD_LENGTH);
    proxypasswd[MAX_CURL_PASSWORD_LENGTH-1] = '\0'; /*To be on safe side*/
  }

  result = Curl_urldecode(data, proxyuser, 0, &conn->http_proxy.user, NULL,
                          FALSE);
  if(!result)
    result = Curl_urldecode(data, proxypasswd, 0, &conn->http_proxy.passwd,
                            NULL, FALSE);
  return result;
}

/* create_conn helper to parse and init proxy values. to be called after unix
   socket init but before any proxy vars are evaluated. */
static CURLcode create_conn_helper_init_proxy(struct connectdata *conn)
{
  char *proxy = NULL;
  char *socksproxy = NULL;
  char *no_proxy = NULL;
  CURLcode result = CURLE_OK;
  struct Curl_easy *data = conn->data;

  /*************************************************************
   * Extract the user and password from the authentication string
   *************************************************************/
  if(conn->bits.proxy_user_passwd) {
    result = parse_proxy_auth(data, conn);
    if(result)
      goto out;
  }

  /*************************************************************
   * Detect what (if any) proxy to use
   *************************************************************/
  if(data->set.str[STRING_PROXY]) {
    proxy = strdup(data->set.str[STRING_PROXY]);
    /* if global proxy is set, this is it */
    if(NULL == proxy) {
      failf(data, "memory shortage");
      result = CURLE_OUT_OF_MEMORY;
      goto out;
    }
  }

  if(data->set.str[STRING_PRE_PROXY]) {
    socksproxy = strdup(data->set.str[STRING_PRE_PROXY]);
    /* if global socks proxy is set, this is it */
    if(NULL == socksproxy) {
      failf(data, "memory shortage");
      result = CURLE_OUT_OF_MEMORY;
      goto out;
    }
  }

  if(!data->set.str[STRING_NOPROXY]) {
    no_proxy = curl_getenv("no_proxy");
    if(!no_proxy)
      no_proxy = curl_getenv("NO_PROXY");
  }

  if(check_noproxy(conn->host.name, data->set.str[STRING_NOPROXY] ?
      data->set.str[STRING_NOPROXY] : no_proxy)) {
    Curl_safefree(proxy);
    Curl_safefree(socksproxy);
  }
#ifndef CURL_DISABLE_HTTP
  else if(!proxy && !socksproxy)
    /* if the host is not in the noproxy list, detect proxy. */
    proxy = detect_proxy(conn);
#endif /* CURL_DISABLE_HTTP */

  Curl_safefree(no_proxy);

#ifdef USE_UNIX_SOCKETS
  /* For the time being do not mix proxy and unix domain sockets. See #1274 */
  if(proxy && conn->unix_domain_socket) {
    free(proxy);
    proxy = NULL;
  }
#endif

  if(proxy && (!*proxy || (conn->handler->flags & PROTOPT_NONETWORK))) {
    free(proxy);  /* Don't bother with an empty proxy string or if the
                     protocol doesn't work with network */
    proxy = NULL;
  }
  if(socksproxy && (!*socksproxy ||
                    (conn->handler->flags & PROTOPT_NONETWORK))) {
    free(socksproxy);  /* Don't bother with an empty socks proxy string or if
                          the protocol doesn't work with network */
    socksproxy = NULL;
  }

  /***********************************************************************
   * If this is supposed to use a proxy, we need to figure out the proxy host
   * name, proxy type and port number, so that we can re-use an existing
   * connection that may exist registered to the same proxy host.
   ***********************************************************************/
  if(proxy || socksproxy) {
    if(proxy) {
      result = parse_proxy(data, conn, proxy, conn->http_proxy.proxytype);
      Curl_safefree(proxy); /* parse_proxy copies the proxy string */
      if(result)
        goto out;
    }

    if(socksproxy) {
      result = parse_proxy(data, conn, socksproxy,
                           conn->socks_proxy.proxytype);
      /* parse_proxy copies the socks proxy string */
      Curl_safefree(socksproxy);
      if(result)
        goto out;
    }

    if(conn->http_proxy.host.rawalloc) {
#ifdef CURL_DISABLE_HTTP
      /* asking for a HTTP proxy is a bit funny when HTTP is disabled... */
      result = CURLE_UNSUPPORTED_PROTOCOL;
      goto out;
#else
      /* force this connection's protocol to become HTTP if compatible */
      if(!(conn->handler->protocol & PROTO_FAMILY_HTTP)) {
        if((conn->handler->flags & PROTOPT_PROXY_AS_HTTP) &&
           !conn->bits.tunnel_proxy)
          conn->handler = &Curl_handler_http;
        else
          /* if not converting to HTTP over the proxy, enforce tunneling */
          conn->bits.tunnel_proxy = TRUE;
      }
      conn->bits.httpproxy = TRUE;
#endif
    }
    else {
      conn->bits.httpproxy = FALSE; /* not a HTTP proxy */
      conn->bits.tunnel_proxy = FALSE; /* no tunneling if not HTTP */
    }

    if(conn->socks_proxy.host.rawalloc) {
      if(!conn->http_proxy.host.rawalloc) {
        /* once a socks proxy */
        if(!conn->socks_proxy.user) {
          conn->socks_proxy.user = conn->http_proxy.user;
          conn->http_proxy.user = NULL;
          Curl_safefree(conn->socks_proxy.passwd);
          conn->socks_proxy.passwd = conn->http_proxy.passwd;
          conn->http_proxy.passwd = NULL;
        }
      }
      conn->bits.socksproxy = TRUE;
    }
    else
      conn->bits.socksproxy = FALSE; /* not a socks proxy */
  }
  else {
    conn->bits.socksproxy = FALSE;
    conn->bits.httpproxy = FALSE;
  }
  conn->bits.proxy = conn->bits.httpproxy || conn->bits.socksproxy;

  if(!conn->bits.proxy) {
    /* we aren't using the proxy after all... */
    conn->bits.proxy = FALSE;
    conn->bits.httpproxy = FALSE;
    conn->bits.socksproxy = FALSE;
    conn->bits.proxy_user_passwd = FALSE;
    conn->bits.tunnel_proxy = FALSE;
  }

out:

  free(socksproxy);
  free(proxy);
  return result;
}
#endif /* CURL_DISABLE_PROXY */

/*
 * parse_url_login()
 *
 * Parse the login details (user name, password and options) from the URL and
 * strip them out of the host name
 *
 * Inputs: data->set.use_netrc (CURLOPT_NETRC)
 *         conn->host.name
 *
 * Outputs: (almost :- all currently undefined)
 *          conn->bits.user_passwd  - non-zero if non-default passwords exist
 *          user                    - non-zero length if defined
 *          passwd                  - non-zero length if defined
 *          options                 - non-zero length if defined
 *          conn->host.name         - remove user name and password
 */
static CURLcode parse_url_login(struct Curl_easy *data,
                                struct connectdata *conn,
                                char **user, char **passwd, char **options)
{
  CURLcode result = CURLE_OK;
  char *userp = NULL;
  char *passwdp = NULL;
  char *optionsp = NULL;

  /* At this point, we're hoping all the other special cases have
   * been taken care of, so conn->host.name is at most
   *    [user[:password][;options]]@]hostname
   *
   * We need somewhere to put the embedded details, so do that first.
   */

  char *ptr = strchr(conn->host.name, '@');
  char *login = conn->host.name;

  DEBUGASSERT(!**user);
  DEBUGASSERT(!**passwd);
  DEBUGASSERT(!**options);
  DEBUGASSERT(conn->handler);

  if(!ptr)
    goto out;

  /* We will now try to extract the
   * possible login information in a string like:
   * ftp://user:password@ftp.my.site:8021/README */
  conn->host.name = ++ptr;

  /* So the hostname is sane.  Only bother interpreting the
   * results if we could care.  It could still be wasted
   * work because it might be overtaken by the programmatically
   * set user/passwd, but doing that first adds more cases here :-(
   */

  if(data->set.use_netrc == CURL_NETRC_REQUIRED)
    goto out;

  /* We could use the login information in the URL so extract it. Only parse
     options if the handler says we should. */
  result =
    Curl_parse_login_details(login, ptr - login - 1,
                             &userp, &passwdp,
                             (conn->handler->flags & PROTOPT_URLOPTIONS)?
                             &optionsp:NULL);
  if(result)
    goto out;

  if(userp) {
    char *newname;

    /* We have a user in the URL */
    conn->bits.userpwd_in_url = TRUE;
    conn->bits.user_passwd = TRUE; /* enable user+password */

    /* Decode the user */
    result = Curl_urldecode(data, userp, 0, &newname, NULL, FALSE);
    if(result) {
      goto out;
    }

    free(*user);
    *user = newname;
  }

  if(passwdp) {
    /* We have a password in the URL so decode it */
    char *newpasswd;
    result = Curl_urldecode(data, passwdp, 0, &newpasswd, NULL, FALSE);
    if(result) {
      goto out;
    }

    free(*passwd);
    *passwd = newpasswd;
  }

  if(optionsp) {
    /* We have an options list in the URL so decode it */
    char *newoptions;
    result = Curl_urldecode(data, optionsp, 0, &newoptions, NULL, FALSE);
    if(result) {
      goto out;
    }

    free(*options);
    *options = newoptions;
  }


  out:

  free(userp);
  free(passwdp);
  free(optionsp);

  return result;
}

/*
 * Curl_parse_login_details()
 *
 * This is used to parse a login string for user name, password and options in
 * the following formats:
 *
 *   user
 *   user:password
 *   user:password;options
 *   user;options
 *   user;options:password
 *   :password
 *   :password;options
 *   ;options
 *   ;options:password
 *
 * Parameters:
 *
 * login    [in]     - The login string.
 * len      [in]     - The length of the login string.
 * userp    [in/out] - The address where a pointer to newly allocated memory
 *                     holding the user will be stored upon completion.
 * passdwp  [in/out] - The address where a pointer to newly allocated memory
 *                     holding the password will be stored upon completion.
 * optionsp [in/out] - The address where a pointer to newly allocated memory
 *                     holding the options will be stored upon completion.
 *
 * Returns CURLE_OK on success.
 */
CURLcode Curl_parse_login_details(const char *login, const size_t len,
                                  char **userp, char **passwdp,
                                  char **optionsp)
{
  CURLcode result = CURLE_OK;
  char *ubuf = NULL;
  char *pbuf = NULL;
  char *obuf = NULL;
  const char *psep = NULL;
  const char *osep = NULL;
  size_t ulen;
  size_t plen;
  size_t olen;

  /* Attempt to find the password separator */
  if(passwdp) {
    psep = strchr(login, ':');

    /* Within the constraint of the login string */
    if(psep >= login + len)
      psep = NULL;
  }

  /* Attempt to find the options separator */
  if(optionsp) {
    osep = strchr(login, ';');

    /* Within the constraint of the login string */
    if(osep >= login + len)
      osep = NULL;
  }

  /* Calculate the portion lengths */
  ulen = (psep ?
          (size_t)(osep && psep > osep ? osep - login : psep - login) :
          (osep ? (size_t)(osep - login) : len));
  plen = (psep ?
          (osep && osep > psep ? (size_t)(osep - psep) :
                                 (size_t)(login + len - psep)) - 1 : 0);
  olen = (osep ?
          (psep && psep > osep ? (size_t)(psep - osep) :
                                 (size_t)(login + len - osep)) - 1 : 0);

  /* Allocate the user portion buffer */
  if(userp && ulen) {
    ubuf = malloc(ulen + 1);
    if(!ubuf)
      result = CURLE_OUT_OF_MEMORY;
  }

  /* Allocate the password portion buffer */
  if(!result && passwdp && plen) {
    pbuf = malloc(plen + 1);
    if(!pbuf) {
      free(ubuf);
      result = CURLE_OUT_OF_MEMORY;
    }
  }

  /* Allocate the options portion buffer */
  if(!result && optionsp && olen) {
    obuf = malloc(olen + 1);
    if(!obuf) {
      free(pbuf);
      free(ubuf);
      result = CURLE_OUT_OF_MEMORY;
    }
  }

  if(!result) {
    /* Store the user portion if necessary */
    if(ubuf) {
      memcpy(ubuf, login, ulen);
      ubuf[ulen] = '\0';
      Curl_safefree(*userp);
      *userp = ubuf;
    }

    /* Store the password portion if necessary */
    if(pbuf) {
      memcpy(pbuf, psep + 1, plen);
      pbuf[plen] = '\0';
      Curl_safefree(*passwdp);
      *passwdp = pbuf;
    }

    /* Store the options portion if necessary */
    if(obuf) {
      memcpy(obuf, osep + 1, olen);
      obuf[olen] = '\0';
      Curl_safefree(*optionsp);
      *optionsp = obuf;
    }
  }

  return result;
}

/*************************************************************
 * Figure out the remote port number and fix it in the URL
 *
 * No matter if we use a proxy or not, we have to figure out the remote
 * port number of various reasons.
 *
 * To be able to detect port number flawlessly, we must not confuse them
 * IPv6-specified addresses in the [0::1] style. (RFC2732)
 *
 * The conn->host.name is currently [user:passwd@]host[:port] where host
 * could be a hostname, IPv4 address or IPv6 address.
 *
 * The port number embedded in the URL is replaced, if necessary.
 *************************************************************/
static CURLcode parse_remote_port(struct Curl_easy *data,
                                  struct connectdata *conn)
{
  char *portptr;
  char endbracket;

  /* Note that at this point, the IPv6 address cannot contain any scope
     suffix as that has already been removed in the parseurlandfillconn()
     function */
  if((1 == sscanf(conn->host.name, "[%*45[0123456789abcdefABCDEF:.]%c",
                  &endbracket)) &&
     (']' == endbracket)) {
    /* this is a RFC2732-style specified IP-address */
    conn->bits.ipv6_ip = TRUE;

    conn->host.name++; /* skip over the starting bracket */
    portptr = strchr(conn->host.name, ']');
    if(portptr) {
      *portptr++ = '\0'; /* zero terminate, killing the bracket */
      if(*portptr) {
        if (*portptr != ':') {
          failf(data, "IPv6 closing bracket followed by '%c'", *portptr);
          return CURLE_URL_MALFORMAT;
        }
      }
      else
        portptr = NULL; /* no port number available */
    }
  }
  else {
#ifdef ENABLE_IPV6
    struct in6_addr in6;
    if(Curl_inet_pton(AF_INET6, conn->host.name, &in6) > 0) {
      /* This is a numerical IPv6 address, meaning this is a wrongly formatted
         URL */
      failf(data, "IPv6 numerical address used in URL without brackets");
      return CURLE_URL_MALFORMAT;
    }
#endif

    portptr = strchr(conn->host.name, ':');
  }

  if(data->set.use_port && data->state.allow_port) {
    /* if set, we use this and ignore the port possibly given in the URL */
    conn->remote_port = (unsigned short)data->set.use_port;
    if(portptr)
      *portptr = '\0'; /* cut off the name there anyway - if there was a port
                      number - since the port number is to be ignored! */
    if(conn->bits.httpproxy) {
      /* we need to create new URL with the new port number */
      char *url;
      char type[12]="";

      if(conn->bits.type_set)
        snprintf(type, sizeof(type), ";type=%c",
                 data->set.prefer_ascii?'A':
                 (data->set.ftp_list_only?'D':'I'));

      /*
       * This synthesized URL isn't always right--suffixes like ;type=A are
       * stripped off. It would be better to work directly from the original
       * URL and simply replace the port part of it.
       */
      url = aprintf("%s://%s%s%s:%hu%s%s%s", conn->given->scheme,
                    conn->bits.ipv6_ip?"[":"", conn->host.name,
                    conn->bits.ipv6_ip?"]":"", conn->remote_port,
                    data->state.slash_removed?"/":"", data->state.path,
                    type);
      if(!url)
        return CURLE_OUT_OF_MEMORY;

      if(data->change.url_alloc) {
        Curl_safefree(data->change.url);
        data->change.url_alloc = FALSE;
      }

      data->change.url = url;
      data->change.url_alloc = TRUE;
    }
  }
  else if(portptr) {
    /* no CURLOPT_PORT given, extract the one from the URL */

    char *rest;
    long port;

    port = strtol(portptr + 1, &rest, 10);  /* Port number must be decimal */

    if((port < 0) || (port > 0xffff)) {
      /* Single unix standard says port numbers are 16 bits long */
      failf(data, "Port number out of range");
      return CURLE_URL_MALFORMAT;
    }

    if(rest[0]) {
      failf(data, "Port number ended with '%c'", rest[0]);
      return CURLE_URL_MALFORMAT;
    }

    if(rest != &portptr[1]) {
      *portptr = '\0'; /* cut off the name there */
      conn->remote_port = curlx_ultous(port);
    }
    else {
      /* Browser behavior adaptation. If there's a colon with no digits after,
         just cut off the name there which makes us ignore the colon and just
         use the default port. Firefox and Chrome both do that. */
      *portptr = '\0';
    }
  }

  /* only if remote_port was not already parsed off the URL we use the
     default port number */
  if(conn->remote_port < 0)
    conn->remote_port = (unsigned short)conn->given->defport;

  return CURLE_OK;
}

/*
 * Override the login details from the URL with that in the CURLOPT_USERPWD
 * option or a .netrc file, if applicable.
 */
static CURLcode override_login(struct Curl_easy *data,
                               struct connectdata *conn,
                               char **userp, char **passwdp, char **optionsp)
{
  if(data->set.str[STRING_USERNAME]) {
    free(*userp);
    *userp = strdup(data->set.str[STRING_USERNAME]);
    if(!*userp)
      return CURLE_OUT_OF_MEMORY;
  }

  if(data->set.str[STRING_PASSWORD]) {
    free(*passwdp);
    *passwdp = strdup(data->set.str[STRING_PASSWORD]);
    if(!*passwdp)
      return CURLE_OUT_OF_MEMORY;
  }

  if(data->set.str[STRING_OPTIONS]) {
    free(*optionsp);
    *optionsp = strdup(data->set.str[STRING_OPTIONS]);
    if(!*optionsp)
      return CURLE_OUT_OF_MEMORY;
  }

  conn->bits.netrc = FALSE;
  if(data->set.use_netrc != CURL_NETRC_IGNORED) {
    int ret = Curl_parsenetrc(conn->host.name,
                              userp, passwdp,
                              data->set.str[STRING_NETRC_FILE]);
    if(ret > 0) {
      infof(data, "Couldn't find host %s in the "
            DOT_CHAR "netrc file; using defaults\n",
            conn->host.name);
    }
    else if(ret < 0) {
      return CURLE_OUT_OF_MEMORY;
    }
    else {
      /* set bits.netrc TRUE to remember that we got the name from a .netrc
         file, so that it is safe to use even if we followed a Location: to a
         different host or similar. */
      conn->bits.netrc = TRUE;

      conn->bits.user_passwd = TRUE; /* enable user+password */
    }
  }

  return CURLE_OK;
}

/*
 * Set the login details so they're available in the connection
 */
static CURLcode set_login(struct connectdata *conn,
                          const char *user, const char *passwd,
                          const char *options)
{
  CURLcode result = CURLE_OK;

  /* If our protocol needs a password and we have none, use the defaults */
  if((conn->handler->flags & PROTOPT_NEEDSPWD) && !conn->bits.user_passwd) {
    /* Store the default user */
    conn->user = strdup(CURL_DEFAULT_USER);

    /* Store the default password */
    if(conn->user)
      conn->passwd = strdup(CURL_DEFAULT_PASSWORD);
    else
      conn->passwd = NULL;

    /* This is the default password, so DON'T set conn->bits.user_passwd */
  }
  else {
    /* Store the user, zero-length if not set */
    conn->user = strdup(user);

    /* Store the password (only if user is present), zero-length if not set */
    if(conn->user)
      conn->passwd = strdup(passwd);
    else
      conn->passwd = NULL;
  }

  if(!conn->user || !conn->passwd)
    result = CURLE_OUT_OF_MEMORY;

  /* Store the options, null if not set */
  if(!result && options[0]) {
    conn->options = strdup(options);

    if(!conn->options)
      result = CURLE_OUT_OF_MEMORY;
  }

  return result;
}

/*
 * Parses a "host:port" string to connect to.
 * The hostname and the port may be empty; in this case, NULL is returned for
 * the hostname and -1 for the port.
 */
static CURLcode parse_connect_to_host_port(struct Curl_easy *data,
                                           const char *host,
                                           char **hostname_result,
                                           int *port_result)
{
  char *host_dup;
  char *hostptr;
  char *host_portno;
  char *portptr;
  int port = -1;

#if defined(CURL_DISABLE_VERBOSE_STRINGS)
  (void) data;
#endif

  *hostname_result = NULL;
  *port_result = -1;

  if(!host || !*host)
    return CURLE_OK;

  host_dup = strdup(host);
  if(!host_dup)
    return CURLE_OUT_OF_MEMORY;

  hostptr = host_dup;

  /* start scanning for port number at this point */
  portptr = hostptr;

  /* detect and extract RFC6874-style IPv6-addresses */
  if(*hostptr == '[') {
#ifdef ENABLE_IPV6
    char *ptr = ++hostptr; /* advance beyond the initial bracket */
    while(*ptr && (ISXDIGIT(*ptr) || (*ptr == ':') || (*ptr == '.')))
      ptr++;
    if(*ptr == '%') {
      /* There might be a zone identifier */
      if(strncmp("%25", ptr, 3))
        infof(data, "Please URL encode %% as %%25, see RFC 6874.\n");
      ptr++;
      /* Allow unreserved characters as defined in RFC 3986 */
      while(*ptr && (ISALPHA(*ptr) || ISXDIGIT(*ptr) || (*ptr == '-') ||
                     (*ptr == '.') || (*ptr == '_') || (*ptr == '~')))
        ptr++;
    }
    if(*ptr == ']')
      /* yeps, it ended nicely with a bracket as well */
      *ptr++ = '\0';
    else
      infof(data, "Invalid IPv6 address format\n");
    portptr = ptr;
    /* Note that if this didn't end with a bracket, we still advanced the
     * hostptr first, but I can't see anything wrong with that as no host
     * name nor a numeric can legally start with a bracket.
     */
#else
    failf(data, "Use of IPv6 in *_CONNECT_TO without IPv6 support built-in!");
    free(host_dup);
    return CURLE_NOT_BUILT_IN;
#endif
  }

  /* Get port number off server.com:1080 */
  host_portno = strchr(portptr, ':');
  if(host_portno) {
    char *endp = NULL;
    *host_portno = '\0'; /* cut off number from host name */
    host_portno++;
    if(*host_portno) {
      long portparse = strtol(host_portno, &endp, 10);
      if((endp && *endp) || (portparse < 0) || (portparse > 65535)) {
        infof(data, "No valid port number in connect to host string (%s)\n",
              host_portno);
        hostptr = NULL;
        port = -1;
      }
      else
        port = (int)portparse; /* we know it will fit */
    }
  }

  /* now, clone the cleaned host name */
  if(hostptr) {
    *hostname_result = strdup(hostptr);
    if(!*hostname_result) {
      free(host_dup);
      return CURLE_OUT_OF_MEMORY;
    }
  }

  *port_result = port;

  free(host_dup);
  return CURLE_OK;
}

/*
 * Parses one "connect to" string in the form:
 * "HOST:PORT:CONNECT-TO-HOST:CONNECT-TO-PORT".
 */
static CURLcode parse_connect_to_string(struct Curl_easy *data,
                                        struct connectdata *conn,
                                        const char *conn_to_host,
                                        char **host_result,
                                        int *port_result)
{
  CURLcode result = CURLE_OK;
  const char *ptr = conn_to_host;
  int host_match = FALSE;
  int port_match = FALSE;

  *host_result = NULL;
  *port_result = -1;

  if(*ptr == ':') {
    /* an empty hostname always matches */
    host_match = TRUE;
    ptr++;
  }
  else {
    /* check whether the URL's hostname matches */
    size_t hostname_to_match_len;
    char *hostname_to_match = aprintf("%s%s%s",
                                      conn->bits.ipv6_ip ? "[" : "",
                                      conn->host.name,
                                      conn->bits.ipv6_ip ? "]" : "");
    if(!hostname_to_match)
      return CURLE_OUT_OF_MEMORY;
    hostname_to_match_len = strlen(hostname_to_match);
    host_match = strncasecompare(ptr, hostname_to_match,
                                 hostname_to_match_len);
    free(hostname_to_match);
    ptr += hostname_to_match_len;

    host_match = host_match && *ptr == ':';
    ptr++;
  }

  if(host_match) {
    if(*ptr == ':') {
      /* an empty port always matches */
      port_match = TRUE;
      ptr++;
    }
    else {
      /* check whether the URL's port matches */
      char *ptr_next = strchr(ptr, ':');
      if(ptr_next) {
        char *endp = NULL;
        long port_to_match = strtol(ptr, &endp, 10);
        if((endp == ptr_next) && (port_to_match == conn->remote_port)) {
          port_match = TRUE;
          ptr = ptr_next + 1;
        }
      }
    }
  }

  if(host_match && port_match) {
    /* parse the hostname and port to connect to */
    result = parse_connect_to_host_port(data, ptr, host_result, port_result);
  }

  return result;
}

/*
 * Processes all strings in the "connect to" slist, and uses the "connect
 * to host" and "connect to port" of the first string that matches.
 */
static CURLcode parse_connect_to_slist(struct Curl_easy *data,
                                       struct connectdata *conn,
                                       struct curl_slist *conn_to_host)
{
  CURLcode result = CURLE_OK;
  char *host = NULL;
  int port = -1;

  while(conn_to_host && !host && port == -1) {
    result = parse_connect_to_string(data, conn, conn_to_host->data,
                                     &host, &port);
    if(result)
      return result;

    if(host && *host) {
      conn->conn_to_host.rawalloc = host;
      conn->conn_to_host.name = host;
      conn->bits.conn_to_host = TRUE;

      infof(data, "Connecting to hostname: %s\n", host);
    }
    else {
      /* no "connect to host" */
      conn->bits.conn_to_host = FALSE;
      Curl_safefree(host);
    }

    if(port >= 0) {
      conn->conn_to_port = port;
      conn->bits.conn_to_port = TRUE;
      infof(data, "Connecting to port: %d\n", port);
    }
    else {
      /* no "connect to port" */
      conn->bits.conn_to_port = FALSE;
      port = -1;
    }

    conn_to_host = conn_to_host->next;
  }

  return result;
}

/*************************************************************
 * Resolve the address of the server or proxy
 *************************************************************/
static CURLcode resolve_server(struct Curl_easy *data,
                               struct connectdata *conn,
                               bool *async)
{
  CURLcode result = CURLE_OK;
  timediff_t timeout_ms = Curl_timeleft(data, NULL, TRUE);

  /*************************************************************
   * Resolve the name of the server or proxy
   *************************************************************/
  if(conn->bits.reuse)
    /* We're reusing the connection - no need to resolve anything, and
       fix_hostname() was called already in create_conn() for the re-use
       case. */
    *async = FALSE;

  else {
    /* this is a fresh connect */
    int rc;
    struct Curl_dns_entry *hostaddr;

#ifdef USE_UNIX_SOCKETS
    if(conn->unix_domain_socket) {
      /* Unix domain sockets are local. The host gets ignored, just use the
       * specified domain socket address. Do not cache "DNS entries". There is
       * no DNS involved and we already have the filesystem path available */
      const char *path = conn->unix_domain_socket;

      hostaddr = calloc(1, sizeof(struct Curl_dns_entry));
      if(!hostaddr)
        result = CURLE_OUT_OF_MEMORY;
      else {
        bool longpath = FALSE;
        hostaddr->addr = Curl_unix2addr(path, &longpath,
                                        conn->abstract_unix_socket);
        if(hostaddr->addr)
          hostaddr->inuse++;
        else {
          /* Long paths are not supported for now */
          if(longpath) {
            failf(data, "Unix socket path too long: '%s'", path);
            result = CURLE_COULDNT_RESOLVE_HOST;
          }
          else
            result = CURLE_OUT_OF_MEMORY;
          free(hostaddr);
          hostaddr = NULL;
        }
      }
    }
    else
#endif
    if(!conn->bits.proxy) {
      struct hostname *connhost;
      if(conn->bits.conn_to_host)
        connhost = &conn->conn_to_host;
      else
        connhost = &conn->host;

      /* If not connecting via a proxy, extract the port from the URL, if it is
       * there, thus overriding any defaults that might have been set above. */
      if(conn->bits.conn_to_port)
        conn->port = conn->conn_to_port;
      else
        conn->port = conn->remote_port;

      /* Resolve target host right on */
      rc = Curl_resolv_timeout(conn, connhost->name, (int)conn->port,
                               &hostaddr, timeout_ms);
      if(rc == CURLRESOLV_PENDING)
        *async = TRUE;

      else if(rc == CURLRESOLV_TIMEDOUT)
        result = CURLE_OPERATION_TIMEDOUT;

      else if(!hostaddr) {
        failf(data, "Couldn't resolve host '%s'", connhost->dispname);
        result =  CURLE_COULDNT_RESOLVE_HOST;
        /* don't return yet, we need to clean up the timeout first */
      }
    }
    else {
      /* This is a proxy that hasn't been resolved yet. */

      struct hostname * const host = conn->bits.socksproxy ?
        &conn->socks_proxy.host : &conn->http_proxy.host;

      /* resolve proxy */
      rc = Curl_resolv_timeout(conn, host->name, (int)conn->port,
                               &hostaddr, timeout_ms);

      if(rc == CURLRESOLV_PENDING)
        *async = TRUE;

      else if(rc == CURLRESOLV_TIMEDOUT)
        result = CURLE_OPERATION_TIMEDOUT;

      else if(!hostaddr) {
        failf(data, "Couldn't resolve proxy '%s'", host->dispname);
        result = CURLE_COULDNT_RESOLVE_PROXY;
        /* don't return yet, we need to clean up the timeout first */
      }
    }
    DEBUGASSERT(conn->dns_entry == NULL);
    conn->dns_entry = hostaddr;
  }

  return result;
}

/*
 * Cleanup the connection just allocated before we can move along and use the
 * previously existing one.  All relevant data is copied over and old_conn is
 * ready for freeing once this function returns.
 */
static void reuse_conn(struct connectdata *old_conn,
                       struct connectdata *conn)
{
  free_fixed_hostname(&old_conn->http_proxy.host);
  free_fixed_hostname(&old_conn->socks_proxy.host);

  free(old_conn->http_proxy.host.rawalloc);
  free(old_conn->socks_proxy.host.rawalloc);

  /* free the SSL config struct from this connection struct as this was
     allocated in vain and is targeted for destruction */
  Curl_free_primary_ssl_config(&old_conn->ssl_config);
  Curl_free_primary_ssl_config(&old_conn->proxy_ssl_config);

  conn->data = old_conn->data;

  /* get the user+password information from the old_conn struct since it may
   * be new for this request even when we re-use an existing connection */
  conn->bits.user_passwd = old_conn->bits.user_passwd;
  if(conn->bits.user_passwd) {
    /* use the new user name and password though */
    Curl_safefree(conn->user);
    Curl_safefree(conn->passwd);
    conn->user = old_conn->user;
    conn->passwd = old_conn->passwd;
    old_conn->user = NULL;
    old_conn->passwd = NULL;
  }

  conn->bits.proxy_user_passwd = old_conn->bits.proxy_user_passwd;
  if(conn->bits.proxy_user_passwd) {
    /* use the new proxy user name and proxy password though */
    Curl_safefree(conn->http_proxy.user);
    Curl_safefree(conn->socks_proxy.user);
    Curl_safefree(conn->http_proxy.passwd);
    Curl_safefree(conn->socks_proxy.passwd);
    conn->http_proxy.user = old_conn->http_proxy.user;
    conn->socks_proxy.user = old_conn->socks_proxy.user;
    conn->http_proxy.passwd = old_conn->http_proxy.passwd;
    conn->socks_proxy.passwd = old_conn->socks_proxy.passwd;
    old_conn->http_proxy.user = NULL;
    old_conn->socks_proxy.user = NULL;
    old_conn->http_proxy.passwd = NULL;
    old_conn->socks_proxy.passwd = NULL;
  }

  /* host can change, when doing keepalive with a proxy or if the case is
     different this time etc */
  free_fixed_hostname(&conn->host);
  free_fixed_hostname(&conn->conn_to_host);
  Curl_safefree(conn->host.rawalloc);
  Curl_safefree(conn->conn_to_host.rawalloc);
  conn->host = old_conn->host;
  conn->conn_to_host = old_conn->conn_to_host;
  conn->conn_to_port = old_conn->conn_to_port;
  conn->remote_port = old_conn->remote_port;

  /* persist connection info in session handle */
  Curl_persistconninfo(conn);

  conn_reset_all_postponed_data(old_conn); /* free buffers */

  /* re-use init */
  conn->bits.reuse = TRUE; /* yes, we're re-using here */

  Curl_safefree(old_conn->user);
  Curl_safefree(old_conn->passwd);
  Curl_safefree(old_conn->http_proxy.user);
  Curl_safefree(old_conn->socks_proxy.user);
  Curl_safefree(old_conn->http_proxy.passwd);
  Curl_safefree(old_conn->socks_proxy.passwd);
  Curl_safefree(old_conn->localdev);

  Curl_llist_destroy(&old_conn->send_pipe, NULL);
  Curl_llist_destroy(&old_conn->recv_pipe, NULL);

  Curl_safefree(old_conn->master_buffer);

#ifdef USE_UNIX_SOCKETS
  Curl_safefree(old_conn->unix_domain_socket);
#endif
}

/**
 * create_conn() sets up a new connectdata struct, or re-uses an already
 * existing one, and resolves host name.
 *
 * if this function returns CURLE_OK and *async is set to TRUE, the resolve
 * response will be coming asynchronously. If *async is FALSE, the name is
 * already resolved.
 *
 * @param data The sessionhandle pointer
 * @param in_connect is set to the next connection data pointer
 * @param async is set TRUE when an async DNS resolution is pending
 * @see Curl_setup_conn()
 *
 * *NOTE* this function assigns the conn->data pointer!
 */

static CURLcode create_conn(struct Curl_easy *data,
                            struct connectdata **in_connect,
                            bool *async)
{
  CURLcode result = CURLE_OK;
  struct connectdata *conn;
  struct connectdata *conn_temp = NULL;
  size_t urllen;
  char *user = NULL;
  char *passwd = NULL;
  char *options = NULL;
  bool reuse;
  bool prot_missing = FALSE;
  bool connections_available = TRUE;
  bool force_reuse = FALSE;
  bool waitpipe = FALSE;
  size_t max_host_connections = Curl_multi_max_host_connections(data->multi);
  size_t max_total_connections = Curl_multi_max_total_connections(data->multi);

  *async = FALSE;

  /*************************************************************
   * Check input data
   *************************************************************/

  if(!data->change.url) {
    result = CURLE_URL_MALFORMAT;
    goto out;
  }

  /* First, split up the current URL in parts so that we can use the
     parts for checking against the already present connections. In order
     to not have to modify everything at once, we allocate a temporary
     connection data struct and fill in for comparison purposes. */
  conn = allocate_conn(data);

  if(!conn) {
    result = CURLE_OUT_OF_MEMORY;
    goto out;
  }

  /* We must set the return variable as soon as possible, so that our
     parent can cleanup any possible allocs we may have done before
     any failure */
  *in_connect = conn;

  /* This initing continues below, see the comment "Continue connectdata
   * initialization here" */

  /***********************************************************
   * We need to allocate memory to store the path in. We get the size of the
   * full URL to be sure, and we need to make it at least 256 bytes since
   * other parts of the code will rely on this fact
   ***********************************************************/
#define LEAST_PATH_ALLOC 256
  urllen = strlen(data->change.url);
  if(urllen < LEAST_PATH_ALLOC)
    urllen = LEAST_PATH_ALLOC;

  /*
   * We malloc() the buffers below urllen+2 to make room for 2 possibilities:
   * 1 - an extra terminating zero
   * 2 - an extra slash (in case a syntax like "www.host.com?moo" is used)
   */

  Curl_safefree(data->state.pathbuffer);
  data->state.path = NULL;

  data->state.pathbuffer = malloc(urllen + 2);
  if(NULL == data->state.pathbuffer) {
    result = CURLE_OUT_OF_MEMORY; /* really bad error */
    goto out;
  }
  data->state.path = data->state.pathbuffer;

  conn->host.rawalloc = malloc(urllen + 2);
  if(NULL == conn->host.rawalloc) {
    Curl_safefree(data->state.pathbuffer);
    data->state.path = NULL;
    result = CURLE_OUT_OF_MEMORY;
    goto out;
  }

  conn->host.name = conn->host.rawalloc;
  conn->host.name[0] = 0;

  user = strdup("");
  passwd = strdup("");
  options = strdup("");
  if(!user || !passwd || !options) {
    result = CURLE_OUT_OF_MEMORY;
    goto out;
  }

  result = parseurlandfillconn(data, conn, &prot_missing, &user, &passwd,
                               &options);
  if(result)
    goto out;

  /*************************************************************
   * No protocol part in URL was used, add it!
   *************************************************************/
  if(prot_missing) {
    /* We're guessing prefixes here and if we're told to use a proxy or if
       we're gonna follow a Location: later or... then we need the protocol
       part added so that we have a valid URL. */
    char *reurl;
    char *ch_lower;

    reurl = aprintf("%s://%s", conn->handler->scheme, data->change.url);

    if(!reurl) {
      result = CURLE_OUT_OF_MEMORY;
      goto out;
    }

    /* Change protocol prefix to lower-case */
    for(ch_lower = reurl; *ch_lower != ':'; ch_lower++)
      *ch_lower = (char)TOLOWER(*ch_lower);

    if(data->change.url_alloc) {
      Curl_safefree(data->change.url);
      data->change.url_alloc = FALSE;
    }

    data->change.url = reurl;
    data->change.url_alloc = TRUE; /* free this later */
  }

  /*************************************************************
   * If the protocol can't handle url query strings, then cut
   * off the unhandable part
   *************************************************************/
  if((conn->given->flags&PROTOPT_NOURLQUERY)) {
    char *path_q_sep = strchr(conn->data->state.path, '?');
    if(path_q_sep) {
      /* according to rfc3986, allow the query (?foo=bar)
         also on protocols that can't handle it.

         cut the string-part after '?'
      */

      /* terminate the string */
      path_q_sep[0] = 0;
    }
  }

  if(data->set.str[STRING_BEARER]) {
    conn->oauth_bearer = strdup(data->set.str[STRING_BEARER]);
    if(!conn->oauth_bearer) {
      result = CURLE_OUT_OF_MEMORY;
      goto out;
    }
  }

#ifdef USE_UNIX_SOCKETS
  if(data->set.str[STRING_UNIX_SOCKET_PATH]) {
    conn->unix_domain_socket = strdup(data->set.str[STRING_UNIX_SOCKET_PATH]);
    if(conn->unix_domain_socket == NULL) {
      result = CURLE_OUT_OF_MEMORY;
      goto out;
    }
    conn->abstract_unix_socket = data->set.abstract_unix_socket;
  }
#endif

  /* After the unix socket init but before the proxy vars are used, parse and
     initialize the proxy vars */
#ifndef CURL_DISABLE_PROXY
  result = create_conn_helper_init_proxy(conn);
  if(result)
    goto out;
#endif

  /*************************************************************
   * If the protocol is using SSL and HTTP proxy is used, we set
   * the tunnel_proxy bit.
   *************************************************************/
  if((conn->given->flags&PROTOPT_SSL) && conn->bits.httpproxy)
    conn->bits.tunnel_proxy = TRUE;

  /*************************************************************
   * Figure out the remote port number and fix it in the URL
   *************************************************************/
  result = parse_remote_port(data, conn);
  if(result)
    goto out;

  /* Check for overridden login details and set them accordingly so they
     they are known when protocol->setup_connection is called! */
  result = override_login(data, conn, &user, &passwd, &options);
  if(result)
    goto out;
  result = set_login(conn, user, passwd, options);
  if(result)
    goto out;

  /*************************************************************
   * Process the "connect to" linked list of hostname/port mappings.
   * Do this after the remote port number has been fixed in the URL.
   *************************************************************/
  result = parse_connect_to_slist(data, conn, data->set.connect_to);
  if(result)
    goto out;

  /*************************************************************
   * IDN-fix the hostnames
   *************************************************************/
  result = fix_hostname(conn, &conn->host);
  if(result)
    goto out;
  if(conn->bits.conn_to_host) {
    result = fix_hostname(conn, &conn->conn_to_host);
    if(result)
      goto out;
  }
  if(conn->bits.httpproxy) {
    result = fix_hostname(conn, &conn->http_proxy.host);
    if(result)
      goto out;
  }
  if(conn->bits.socksproxy) {
    result = fix_hostname(conn, &conn->socks_proxy.host);
    if(result)
      goto out;
  }

  /*************************************************************
   * Check whether the host and the "connect to host" are equal.
   * Do this after the hostnames have been IDN-fixed.
   *************************************************************/
  if(conn->bits.conn_to_host &&
     strcasecompare(conn->conn_to_host.name, conn->host.name)) {
    conn->bits.conn_to_host = FALSE;
  }

  /*************************************************************
   * Check whether the port and the "connect to port" are equal.
   * Do this after the remote port number has been fixed in the URL.
   *************************************************************/
  if(conn->bits.conn_to_port && conn->conn_to_port == conn->remote_port) {
    conn->bits.conn_to_port = FALSE;
  }

  /*************************************************************
   * If the "connect to" feature is used with an HTTP proxy,
   * we set the tunnel_proxy bit.
   *************************************************************/
  if((conn->bits.conn_to_host || conn->bits.conn_to_port) &&
      conn->bits.httpproxy)
    conn->bits.tunnel_proxy = TRUE;

  /*************************************************************
   * Setup internals depending on protocol. Needs to be done after
   * we figured out what/if proxy to use.
   *************************************************************/
  result = setup_connection_internals(conn);
  if(result)
    goto out;

  conn->recv[FIRSTSOCKET] = Curl_recv_plain;
  conn->send[FIRSTSOCKET] = Curl_send_plain;
  conn->recv[SECONDARYSOCKET] = Curl_recv_plain;
  conn->send[SECONDARYSOCKET] = Curl_send_plain;

  conn->bits.tcp_fastopen = data->set.tcp_fastopen;

  /***********************************************************************
   * file: is a special case in that it doesn't need a network connection
   ***********************************************************************/
#ifndef CURL_DISABLE_FILE
  if(conn->handler->flags & PROTOPT_NONETWORK) {
    bool done;
    /* this is supposed to be the connect function so we better at least check
       that the file is present here! */
    DEBUGASSERT(conn->handler->connect_it);
    result = conn->handler->connect_it(conn, &done);

    /* Setup a "faked" transfer that'll do nothing */
    if(!result) {
      conn->data = data;
      conn->bits.tcpconnect[FIRSTSOCKET] = TRUE; /* we are "connected */

      Curl_conncache_add_conn(data->state.conn_cache, conn);

      /*
       * Setup whatever necessary for a resumed transfer
       */
      result = setup_range(data);
      if(result) {
        DEBUGASSERT(conn->handler->done);
        /* we ignore the return code for the protocol-specific DONE */
        (void)conn->handler->done(conn, result, FALSE);
        goto out;
      }

      Curl_setup_transfer(conn, -1, -1, FALSE, NULL, /* no download */
                          -1, NULL); /* no upload */
    }

    /* since we skip do_init() */
    Curl_init_do(data, conn);

    goto out;
  }
#endif

  /* Get a cloned copy of the SSL config situation stored in the
     connection struct. But to get this going nicely, we must first make
     sure that the strings in the master copy are pointing to the correct
     strings in the session handle strings array!

     Keep in mind that the pointers in the master copy are pointing to strings
     that will be freed as part of the Curl_easy struct, but all cloned
     copies will be separately allocated.
  */
  data->set.ssl.primary.CApath = data->set.str[STRING_SSL_CAPATH_ORIG];
  data->set.proxy_ssl.primary.CApath = data->set.str[STRING_SSL_CAPATH_PROXY];
  data->set.ssl.primary.CAfile = data->set.str[STRING_SSL_CAFILE_ORIG];
  data->set.proxy_ssl.primary.CAfile = data->set.str[STRING_SSL_CAFILE_PROXY];
  data->set.ssl.primary.random_file = data->set.str[STRING_SSL_RANDOM_FILE];
  data->set.proxy_ssl.primary.random_file =
    data->set.str[STRING_SSL_RANDOM_FILE];
  data->set.ssl.primary.egdsocket = data->set.str[STRING_SSL_EGDSOCKET];
  data->set.proxy_ssl.primary.egdsocket = data->set.str[STRING_SSL_EGDSOCKET];
  data->set.ssl.primary.cipher_list =
    data->set.str[STRING_SSL_CIPHER_LIST_ORIG];
  data->set.proxy_ssl.primary.cipher_list =
    data->set.str[STRING_SSL_CIPHER_LIST_PROXY];

  data->set.ssl.CRLfile = data->set.str[STRING_SSL_CRLFILE_ORIG];
  data->set.proxy_ssl.CRLfile = data->set.str[STRING_SSL_CRLFILE_PROXY];
  data->set.ssl.issuercert = data->set.str[STRING_SSL_ISSUERCERT_ORIG];
  data->set.proxy_ssl.issuercert = data->set.str[STRING_SSL_ISSUERCERT_PROXY];
  data->set.ssl.cert = data->set.str[STRING_CERT_ORIG];
  data->set.proxy_ssl.cert = data->set.str[STRING_CERT_PROXY];
  data->set.ssl.cert_type = data->set.str[STRING_CERT_TYPE_ORIG];
  data->set.proxy_ssl.cert_type = data->set.str[STRING_CERT_TYPE_PROXY];
  data->set.ssl.key = data->set.str[STRING_KEY_ORIG];
  data->set.proxy_ssl.key = data->set.str[STRING_KEY_PROXY];
  data->set.ssl.key_type = data->set.str[STRING_KEY_TYPE_ORIG];
  data->set.proxy_ssl.key_type = data->set.str[STRING_KEY_TYPE_PROXY];
  data->set.ssl.key_passwd = data->set.str[STRING_KEY_PASSWD_ORIG];
  data->set.proxy_ssl.key_passwd = data->set.str[STRING_KEY_PASSWD_PROXY];
  data->set.ssl.primary.clientcert = data->set.str[STRING_CERT_ORIG];
  data->set.proxy_ssl.primary.clientcert = data->set.str[STRING_CERT_PROXY];
#ifdef USE_TLS_SRP
  data->set.ssl.username = data->set.str[STRING_TLSAUTH_USERNAME_ORIG];
  data->set.proxy_ssl.username = data->set.str[STRING_TLSAUTH_USERNAME_PROXY];
  data->set.ssl.password = data->set.str[STRING_TLSAUTH_PASSWORD_ORIG];
  data->set.proxy_ssl.password = data->set.str[STRING_TLSAUTH_PASSWORD_PROXY];
#endif

  if(!Curl_clone_primary_ssl_config(&data->set.ssl.primary,
     &conn->ssl_config)) {
    result = CURLE_OUT_OF_MEMORY;
    goto out;
  }

  if(!Curl_clone_primary_ssl_config(&data->set.proxy_ssl.primary,
                                    &conn->proxy_ssl_config)) {
    result = CURLE_OUT_OF_MEMORY;
    goto out;
  }

  prune_dead_connections(data);

  /*************************************************************
   * Check the current list of connections to see if we can
   * re-use an already existing one or if we have to create a
   * new one.
   *************************************************************/

  /* reuse_fresh is TRUE if we are told to use a new connection by force, but
     we only acknowledge this option if this is not a re-used connection
     already (which happens due to follow-location or during a HTTP
     authentication phase). */
  if(data->set.reuse_fresh && !data->state.this_is_a_follow)
    reuse = FALSE;
  else
    reuse = ConnectionExists(data, conn, &conn_temp, &force_reuse, &waitpipe);

  /* If we found a reusable connection that is now marked as in use, we may
     still want to open a new connection if we are pipelining. */
  if(reuse && !force_reuse && IsPipeliningPossible(data, conn_temp)) {
    size_t pipelen = conn_temp->send_pipe.size + conn_temp->recv_pipe.size;
    if(pipelen > 0) {
      infof(data, "Found connection %ld, with requests in the pipe (%zu)\n",
            conn_temp->connection_id, pipelen);

      if(Curl_conncache_bundle_size(conn_temp) < max_host_connections &&
         Curl_conncache_size(data) < max_total_connections) {
        /* We want a new connection anyway */
        reuse = FALSE;

        infof(data, "We can reuse, but we want a new connection anyway\n");
        Curl_conncache_return_conn(conn_temp);
      }
    }
  }

  if(reuse) {
    /*
     * We already have a connection for this, we got the former connection
     * in the conn_temp variable and thus we need to cleanup the one we
     * just allocated before we can move along and use the previously
     * existing one.
     */
    reuse_conn(conn, conn_temp);
#ifdef USE_SSL
    free(conn->ssl_extra);
#endif
    free(conn);          /* we don't need this anymore */
    conn = conn_temp;
    *in_connect = conn;

    infof(data, "Re-using existing connection! (#%ld) with %s %s\n",
          conn->connection_id,
          conn->bits.proxy?"proxy":"host",
          conn->socks_proxy.host.name ? conn->socks_proxy.host.dispname :
          conn->http_proxy.host.name ? conn->http_proxy.host.dispname :
                                       conn->host.dispname);
  }
  else {
    /* We have decided that we want a new connection. However, we may not
       be able to do that if we have reached the limit of how many
       connections we are allowed to open. */

    if(conn->handler->flags & PROTOPT_ALPN_NPN) {
      /* The protocol wants it, so set the bits if enabled in the easy handle
         (default) */
      if(data->set.ssl_enable_alpn)
        conn->bits.tls_enable_alpn = TRUE;
      if(data->set.ssl_enable_npn)
        conn->bits.tls_enable_npn = TRUE;
    }

    if(waitpipe)
      /* There is a connection that *might* become usable for pipelining
         "soon", and we wait for that */
      connections_available = FALSE;
    else {
      /* this gets a lock on the conncache */
      struct connectbundle *bundle =
        Curl_conncache_find_bundle(conn, data->state.conn_cache);

      if(max_host_connections > 0 && bundle &&
         (bundle->num_connections >= max_host_connections)) {
        struct connectdata *conn_candidate;

        /* The bundle is full. Extract the oldest connection. */
        conn_candidate = Curl_conncache_extract_bundle(data, bundle);
        Curl_conncache_unlock(conn);

        if(conn_candidate) {
          /* Set the connection's owner correctly, then kill it */
          conn_candidate->data = data;
          (void)Curl_disconnect(conn_candidate, /* dead_connection */ FALSE);
        }
        else {
          infof(data, "No more connections allowed to host: %d\n",
                max_host_connections);
          connections_available = FALSE;
        }
      }
      else
        Curl_conncache_unlock(conn);

    }

    if(connections_available &&
       (max_total_connections > 0) &&
       (Curl_conncache_size(data) >= max_total_connections)) {
      struct connectdata *conn_candidate;

      /* The cache is full. Let's see if we can kill a connection. */
      conn_candidate = Curl_conncache_extract_oldest(data);

      if(conn_candidate) {
        /* Set the connection's owner correctly, then kill it */
        conn_candidate->data = data;
        (void)Curl_disconnect(conn_candidate, /* dead_connection */ FALSE);
      }
      else {
        infof(data, "No connections available in cache\n");
        connections_available = FALSE;
      }
    }

    if(!connections_available) {
      infof(data, "No connections available.\n");

      conn_free(conn);
      *in_connect = NULL;

      result = CURLE_NO_CONNECTION_AVAILABLE;
      goto out;
    }
    else {
      /* Mark the connection as used, before we add it */
      conn->inuse = TRUE;

      /*
       * This is a brand new connection, so let's store it in the connection
       * cache of ours!
       */
      Curl_conncache_add_conn(data->state.conn_cache, conn);
    }

#if defined(USE_NTLM)
    /* If NTLM is requested in a part of this connection, make sure we don't
       assume the state is fine as this is a fresh connection and NTLM is
       connection based. */
    if((data->state.authhost.picked & (CURLAUTH_NTLM | CURLAUTH_NTLM_WB)) &&
       data->state.authhost.done) {
      infof(data, "NTLM picked AND auth done set, clear picked!\n");
      data->state.authhost.picked = CURLAUTH_NONE;
      data->state.authhost.done = FALSE;
    }

    if((data->state.authproxy.picked & (CURLAUTH_NTLM | CURLAUTH_NTLM_WB)) &&
       data->state.authproxy.done) {
      infof(data, "NTLM-proxy picked AND auth done set, clear picked!\n");
      data->state.authproxy.picked = CURLAUTH_NONE;
      data->state.authproxy.done = FALSE;
    }
#endif
  }

  /* Setup and init stuff before DO starts, in preparing for the transfer. */
  Curl_init_do(data, conn);

  /*
   * Setup whatever necessary for a resumed transfer
   */
  result = setup_range(data);
  if(result)
    goto out;

  /* Continue connectdata initialization here. */

  /*
   * Inherit the proper values from the urldata struct AFTER we have arranged
   * the persistent connection stuff
   */
  conn->seek_func = data->set.seek_func;
  conn->seek_client = data->set.seek_client;

  /*************************************************************
   * Resolve the address of the server or proxy
   *************************************************************/
  result = resolve_server(data, conn, async);

out:

  free(options);
  free(passwd);
  free(user);
  return result;
}

/* Curl_setup_conn() is called after the name resolve initiated in
 * create_conn() is all done.
 *
 * Curl_setup_conn() also handles reused connections
 *
 * conn->data MUST already have been setup fine (in create_conn)
 */

CURLcode Curl_setup_conn(struct connectdata *conn,
                         bool *protocol_done)
{
  CURLcode result = CURLE_OK;
  struct Curl_easy *data = conn->data;

  Curl_pgrsTime(data, TIMER_NAMELOOKUP);

  if(conn->handler->flags & PROTOPT_NONETWORK) {
    /* nothing to setup when not using a network */
    *protocol_done = TRUE;
    return result;
  }
  *protocol_done = FALSE; /* default to not done */

  /* set proxy_connect_closed to false unconditionally already here since it
     is used strictly to provide extra information to a parent function in the
     case of proxy CONNECT failures and we must make sure we don't have it
     lingering set from a previous invoke */
  conn->bits.proxy_connect_closed = FALSE;

  /*
   * Set user-agent. Used for HTTP, but since we can attempt to tunnel
   * basically anything through a http proxy we can't limit this based on
   * protocol.
   */
  if(data->set.str[STRING_USERAGENT]) {
    Curl_safefree(conn->allocptr.uagent);
    conn->allocptr.uagent =
      aprintf("User-Agent: %s\r\n", data->set.str[STRING_USERAGENT]);
    if(!conn->allocptr.uagent)
      return CURLE_OUT_OF_MEMORY;
  }

  data->req.headerbytecount = 0;

#ifdef CURL_DO_LINEEND_CONV
  data->state.crlf_conversions = 0; /* reset CRLF conversion counter */
#endif /* CURL_DO_LINEEND_CONV */

  /* set start time here for timeout purposes in the connect procedure, it
     is later set again for the progress meter purpose */
  conn->now = Curl_now();

  if(CURL_SOCKET_BAD == conn->sock[FIRSTSOCKET]) {
    conn->bits.tcpconnect[FIRSTSOCKET] = FALSE;
    result = Curl_connecthost(conn, conn->dns_entry);
    if(result)
      return result;
  }
  else {
    Curl_pgrsTime(data, TIMER_CONNECT);    /* we're connected already */
    Curl_pgrsTime(data, TIMER_APPCONNECT); /* we're connected already */
    conn->bits.tcpconnect[FIRSTSOCKET] = TRUE;
    *protocol_done = TRUE;
    Curl_updateconninfo(conn, conn->sock[FIRSTSOCKET]);
    Curl_verboseconnect(conn);
  }

  conn->now = Curl_now(); /* time this *after* the connect is done, we set
                             this here perhaps a second time */
  return result;
}

CURLcode Curl_connect(struct Curl_easy *data,
                      struct connectdata **in_connect,
                      bool *asyncp,
                      bool *protocol_done)
{
  CURLcode result;

  *asyncp = FALSE; /* assume synchronous resolves by default */

  /* call the stuff that needs to be called */
  result = create_conn(data, in_connect, asyncp);

  if(!result) {
    /* no error */
    if((*in_connect)->send_pipe.size || (*in_connect)->recv_pipe.size)
      /* pipelining */
      *protocol_done = TRUE;
    else if(!*asyncp) {
      /* DNS resolution is done: that's either because this is a reused
         connection, in which case DNS was unnecessary, or because DNS
         really did finish already (synch resolver/fast async resolve) */
      result = Curl_setup_conn(*in_connect, protocol_done);
    }
  }

  if(result == CURLE_NO_CONNECTION_AVAILABLE) {
    *in_connect = NULL;
    return result;
  }

  if(result && *in_connect) {
    /* We're not allowed to return failure with memory left allocated
       in the connectdata struct, free those here */
    Curl_disconnect(*in_connect, FALSE); /* close the connection */
    *in_connect = NULL;           /* return a NULL */
  }

  return result;
}

/*
 * Curl_init_do() inits the readwrite session. This is inited each time (in
 * the DO function before the protocol-specific DO functions are invoked) for
 * a transfer, sometimes multiple times on the same Curl_easy. Make sure
 * nothing in here depends on stuff that are setup dynamically for the
 * transfer.
 *
 * Allow this function to get called with 'conn' set to NULL.
 */

CURLcode Curl_init_do(struct Curl_easy *data, struct connectdata *conn)
{
  struct SingleRequest *k = &data->req;

  conn->bits.do_more = FALSE; /* by default there's no curl_do_more() to
                                 use */

  data->state.done = FALSE; /* *_done() is not called yet */
  data->state.expect100header = FALSE;

  /* if the protocol used doesn't support wildcards, switch it off */
  if(data->state.wildcardmatch &&
     !(conn->handler->flags & PROTOPT_WILDCARD))
    data->state.wildcardmatch = FALSE;

  if(data->set.opt_no_body)
    /* in HTTP lingo, no body means using the HEAD request... */
    data->set.httpreq = HTTPREQ_HEAD;
  else if(HTTPREQ_HEAD == data->set.httpreq)
    /* ... but if unset there really is no perfect method that is the
       "opposite" of HEAD but in reality most people probably think GET
       then. The important thing is that we can't let it remain HEAD if the
       opt_no_body is set FALSE since then we'll behave wrong when getting
       HTTP. */
    data->set.httpreq = HTTPREQ_GET;

  k->start = Curl_now(); /* start time */
  k->now = k->start;   /* current time is now */
  k->header = TRUE; /* assume header */

  k->bytecount = 0;

  k->buf = data->state.buffer;
  k->hbufp = data->state.headerbuff;
  k->ignorebody = FALSE;

  Curl_speedinit(data);

  Curl_pgrsSetUploadCounter(data, 0);
  Curl_pgrsSetDownloadCounter(data, 0);

  return CURLE_OK;
}

/*
* get_protocol_family()
*
* This is used to return the protocol family for a given protocol.
*
* Parameters:
*
* protocol  [in]  - A single bit protocol identifier such as HTTP or HTTPS.
*
* Returns the family as a single bit protocol identifier.
*/

static unsigned int get_protocol_family(unsigned int protocol)
{
  unsigned int family;

  switch(protocol) {
  case CURLPROTO_HTTP:
  case CURLPROTO_HTTPS:
    family = CURLPROTO_HTTP;
    break;

  case CURLPROTO_FTP:
  case CURLPROTO_FTPS:
    family = CURLPROTO_FTP;
    break;

  case CURLPROTO_SCP:
    family = CURLPROTO_SCP;
    break;

  case CURLPROTO_SFTP:
    family = CURLPROTO_SFTP;
    break;

  case CURLPROTO_TELNET:
    family = CURLPROTO_TELNET;
    break;

  case CURLPROTO_LDAP:
  case CURLPROTO_LDAPS:
    family = CURLPROTO_LDAP;
    break;

  case CURLPROTO_DICT:
    family = CURLPROTO_DICT;
    break;

  case CURLPROTO_FILE:
    family = CURLPROTO_FILE;
    break;

  case CURLPROTO_TFTP:
    family = CURLPROTO_TFTP;
    break;

  case CURLPROTO_IMAP:
  case CURLPROTO_IMAPS:
    family = CURLPROTO_IMAP;
    break;

  case CURLPROTO_POP3:
  case CURLPROTO_POP3S:
    family = CURLPROTO_POP3;
    break;

  case CURLPROTO_SMTP:
  case CURLPROTO_SMTPS:
      family = CURLPROTO_SMTP;
      break;

  case CURLPROTO_RTSP:
    family = CURLPROTO_RTSP;
    break;

  case CURLPROTO_RTMP:
  case CURLPROTO_RTMPS:
    family = CURLPROTO_RTMP;
    break;

  case CURLPROTO_RTMPT:
  case CURLPROTO_RTMPTS:
    family = CURLPROTO_RTMPT;
    break;

  case CURLPROTO_RTMPE:
    family = CURLPROTO_RTMPE;
    break;

  case CURLPROTO_RTMPTE:
    family = CURLPROTO_RTMPTE;
    break;

  case CURLPROTO_GOPHER:
    family = CURLPROTO_GOPHER;
    break;

  case CURLPROTO_SMB:
  case CURLPROTO_SMBS:
    family = CURLPROTO_SMB;
    break;

  default:
      family = 0;
      break;
  }

  return family;
}