summaryrefslogtreecommitdiffstats
path: root/dbus/dbus-connection.c
blob: a08aa36698e7c20d666854eebdfbbdd4b5aea05d (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
/* -*- mode: C; c-file-style: "gnu" -*- */
/* dbus-connection.c DBusConnection object
 *
 * Copyright (C) 2002, 2003, 2004, 2005  Red Hat Inc.
 *
 * Licensed under the Academic Free License version 2.1
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <config.h>
#include "dbus-shared.h"
#include "dbus-connection.h"
#include "dbus-list.h"
#include "dbus-timeout.h"
#include "dbus-transport.h"
#include "dbus-watch.h"
#include "dbus-connection-internal.h"
#include "dbus-list.h"
#include "dbus-hash.h"
#include "dbus-message-internal.h"
#include "dbus-threads.h"
#include "dbus-protocol.h"
#include "dbus-dataslot.h"
#include "dbus-string.h"
#include "dbus-pending-call.h"
#include "dbus-object-tree.h"
#include "dbus-threads-internal.h"

#ifdef DBUS_DISABLE_CHECKS
#define TOOK_LOCK_CHECK(connection)
#define RELEASING_LOCK_CHECK(connection)
#define HAVE_LOCK_CHECK(connection)
#else
#define TOOK_LOCK_CHECK(connection) do {                \
    _dbus_assert (!(connection)->have_connection_lock); \
    (connection)->have_connection_lock = TRUE;          \
  } while (0)
#define RELEASING_LOCK_CHECK(connection) do {            \
    _dbus_assert ((connection)->have_connection_lock);   \
    (connection)->have_connection_lock = FALSE;          \
  } while (0)
#define HAVE_LOCK_CHECK(connection)        _dbus_assert ((connection)->have_connection_lock)
/* A "DO_NOT_HAVE_LOCK_CHECK" is impossible since we need the lock to check the flag */
#endif

#define TRACE_LOCKS 1

#define CONNECTION_LOCK(connection)   do {                                      \
    if (TRACE_LOCKS) { _dbus_verbose ("  LOCK: %s\n", _DBUS_FUNCTION_NAME); }   \
    _dbus_mutex_lock ((connection)->mutex);                                      \
    TOOK_LOCK_CHECK (connection);                                               \
  } while (0)

#define CONNECTION_UNLOCK(connection) do {                                              \
    if (TRACE_LOCKS) { _dbus_verbose ("  UNLOCK: %s\n", _DBUS_FUNCTION_NAME);  }        \
    RELEASING_LOCK_CHECK (connection);                                                  \
    _dbus_mutex_unlock ((connection)->mutex);                                            \
  } while (0)

#define DISPATCH_STATUS_NAME(s)                                            \
                     ((s) == DBUS_DISPATCH_COMPLETE ? "complete" :         \
                      (s) == DBUS_DISPATCH_DATA_REMAINS ? "data remains" : \
                      (s) == DBUS_DISPATCH_NEED_MEMORY ? "need memory" :   \
                      "???")

/**
 * @defgroup DBusConnection DBusConnection
 * @ingroup  DBus
 * @brief Connection to another application
 *
 * A DBusConnection represents a connection to another
 * application. Messages can be sent and received via this connection.
 * The other application may be a message bus; for convenience, the
 * function dbus_bus_get() is provided to automatically open a
 * connection to the well-known message buses.
 * 
 * In brief a DBusConnection is a message queue associated with some
 * message transport mechanism such as a socket.  The connection
 * maintains a queue of incoming messages and a queue of outgoing
 * messages.
 *
 * Incoming messages are normally processed by calling
 * dbus_connection_dispatch(). dbus_connection_dispatch() runs any
 * handlers registered for the topmost message in the message queue,
 * then discards the message, then returns.
 * 
 * dbus_connection_get_dispatch_status() indicates whether
 * messages are currently in the queue that need dispatching.
 * dbus_connection_set_dispatch_status_function() allows
 * you to set a function to be used to monitor the dispatch status.
 *
 * If you're using GLib or Qt add-on libraries for D-BUS, there are
 * special convenience APIs in those libraries that hide
 * all the details of dispatch and watch/timeout monitoring.
 * For example, dbus_connection_setup_with_g_main().
 *
 * If you aren't using these add-on libraries, you have to manually
 * call dbus_connection_set_dispatch_status_function(),
 * dbus_connection_set_watch_functions(),
 * dbus_connection_set_timeout_functions() providing appropriate
 * functions to integrate the connection with your application's main
 * loop.
 *
 * When you use dbus_connection_send() or one of its variants to send
 * a message, the message is added to the outgoing queue.  It's
 * actually written to the network later; either in
 * dbus_watch_handle() invoked by your main loop, or in
 * dbus_connection_flush() which blocks until it can write out the
 * entire outgoing queue. The GLib/Qt add-on libraries again
 * handle the details here for you by setting up watch functions.
 *
 * When a connection is disconnected, you are guaranteed to get a
 * signal "Disconnected" from the interface
 * #DBUS_INTERFACE_LOCAL, path
 * #DBUS_PATH_LOCAL.
 *
 * You may not drop the last reference to a #DBusConnection
 * until that connection has been disconnected.
 *
 * You may dispatch the unprocessed incoming message queue even if the
 * connection is disconnected. However, "Disconnected" will always be
 * the last message in the queue (obviously no messages are received
 * after disconnection).
 *
 * #DBusConnection has thread locks and drops them when invoking user
 * callbacks, so in general is transparently threadsafe. However,
 * #DBusMessage does NOT have thread locks; you must not send the same
 * message to multiple #DBusConnection that will be used from
 * different threads.
 */

/**
 * @defgroup DBusConnectionInternals DBusConnection implementation details
 * @ingroup  DBusInternals
 * @brief Implementation details of DBusConnection
 *
 * @{
 */

/**
 * Internal struct representing a message filter function 
 */
typedef struct DBusMessageFilter DBusMessageFilter;

/**
 * Internal struct representing a message filter function 
 */
struct DBusMessageFilter
{
  DBusAtomic refcount; /**< Reference count */
  DBusHandleMessageFunction function; /**< Function to call to filter */
  void *user_data; /**< User data for the function */
  DBusFreeFunction free_user_data_function; /**< Function to free the user data */
};


/**
 * Internals of DBusPreallocatedSend
 */
struct DBusPreallocatedSend
{
  DBusConnection *connection; /**< Connection we'd send the message to */
  DBusList *queue_link;       /**< Preallocated link in the queue */
  DBusList *counter_link;     /**< Preallocated link in the resource counter */
};

static dbus_bool_t _dbus_modify_sigpipe = TRUE;

/**
 * Implementation details of DBusConnection. All fields are private.
 */
struct DBusConnection
{
  DBusAtomic refcount; /**< Reference count. */

  DBusMutex *mutex; /**< Lock on the entire DBusConnection */

  DBusMutex *dispatch_mutex;     /**< Protects dispatch_acquired */
  DBusCondVar *dispatch_cond;    /**< Notify when dispatch_acquired is available */
  DBusMutex *io_path_mutex;      /**< Protects io_path_acquired */
  DBusCondVar *io_path_cond;     /**< Notify when io_path_acquired is available */
  
  DBusList *outgoing_messages; /**< Queue of messages we need to send, send the end of the list first. */
  DBusList *incoming_messages; /**< Queue of messages we have received, end of the list received most recently. */

  DBusMessage *message_borrowed; /**< Filled in if the first incoming message has been borrowed;
                                  *   dispatch_acquired will be set by the borrower
                                  */
  
  int n_outgoing;              /**< Length of outgoing queue. */
  int n_incoming;              /**< Length of incoming queue. */

  DBusCounter *outgoing_counter; /**< Counts size of outgoing messages. */
  
  DBusTransport *transport;    /**< Object that sends/receives messages over network. */
  DBusWatchList *watches;      /**< Stores active watches. */
  DBusTimeoutList *timeouts;   /**< Stores active timeouts. */
  
  DBusList *filter_list;        /**< List of filters. */

  DBusDataSlotList slot_list;   /**< Data stored by allocated integer ID */

  DBusHashTable *pending_replies;  /**< Hash of message serials to #DBusPendingCall. */  
  
  dbus_uint32_t client_serial;       /**< Client serial. Increments each time a message is sent  */
  DBusList *disconnect_message_link; /**< Preallocated list node for queueing the disconnection message */

  DBusWakeupMainFunction wakeup_main_function; /**< Function to wake up the mainloop  */
  void *wakeup_main_data; /**< Application data for wakeup_main_function */
  DBusFreeFunction free_wakeup_main_data; /**< free wakeup_main_data */

  DBusDispatchStatusFunction dispatch_status_function; /**< Function on dispatch status changes  */
  void *dispatch_status_data; /**< Application data for dispatch_status_function */
  DBusFreeFunction free_dispatch_status_data; /**< free dispatch_status_data */

  DBusDispatchStatus last_dispatch_status; /**< The last dispatch status we reported to the application. */

  DBusList *link_cache; /**< A cache of linked list links to prevent contention
                         *   for the global linked list mempool lock
                         */
  DBusObjectTree *objects; /**< Object path handlers registered with this connection */

  char *server_guid; /**< GUID of server if we are in shared_connections, #NULL if server GUID is unknown or connection is private */

  unsigned int shareable : 1; /**< #TRUE if connection can go in shared_connections once we know the GUID */
  
  unsigned int dispatch_acquired : 1; /**< Someone has dispatch path (can drain incoming queue) */
  unsigned int io_path_acquired : 1;  /**< Someone has transport io path (can use the transport to read/write messages) */
  
  unsigned int exit_on_disconnect : 1; /**< If #TRUE, exit after handling disconnect signal */
  
#ifndef DBUS_DISABLE_CHECKS
  unsigned int have_connection_lock : 1; /**< Used to check locking */
#endif
  
#ifndef DBUS_DISABLE_CHECKS
  int generation; /**< _dbus_current_generation that should correspond to this connection */
#endif 
};

static DBusDispatchStatus _dbus_connection_get_dispatch_status_unlocked      (DBusConnection     *connection);
static void               _dbus_connection_update_dispatch_status_and_unlock (DBusConnection     *connection,
                                                                              DBusDispatchStatus  new_status);
static void               _dbus_connection_last_unref                        (DBusConnection     *connection);
static void               _dbus_connection_acquire_dispatch                  (DBusConnection     *connection);
static void               _dbus_connection_release_dispatch                  (DBusConnection     *connection);

static DBusMessageFilter *
_dbus_message_filter_ref (DBusMessageFilter *filter)
{
  _dbus_assert (filter->refcount.value > 0);
  _dbus_atomic_inc (&filter->refcount);

  return filter;
}

static void
_dbus_message_filter_unref (DBusMessageFilter *filter)
{
  _dbus_assert (filter->refcount.value > 0);

  if (_dbus_atomic_dec (&filter->refcount) == 1)
    {
      if (filter->free_user_data_function)
        (* filter->free_user_data_function) (filter->user_data);
      
      dbus_free (filter);
    }
}

/**
 * Acquires the connection lock.
 *
 * @param connection the connection.
 */
void
_dbus_connection_lock (DBusConnection *connection)
{
  CONNECTION_LOCK (connection);
}

/**
 * Releases the connection lock.
 *
 * @param connection the connection.
 */
void
_dbus_connection_unlock (DBusConnection *connection)
{
  CONNECTION_UNLOCK (connection);
}

/**
 * Wakes up the main loop if it is sleeping
 * Needed if we're e.g. queueing outgoing messages
 * on a thread while the mainloop sleeps.
 *
 * @param connection the connection.
 */
static void
_dbus_connection_wakeup_mainloop (DBusConnection *connection)
{
  if (connection->wakeup_main_function)
    (*connection->wakeup_main_function) (connection->wakeup_main_data);
}

#ifdef DBUS_BUILD_TESTS
/* For now this function isn't used */
/**
 * Adds a message to the incoming message queue, returning #FALSE
 * if there's insufficient memory to queue the message.
 * Does not take over refcount of the message.
 *
 * @param connection the connection.
 * @param message the message to queue.
 * @returns #TRUE on success.
 */
dbus_bool_t
_dbus_connection_queue_received_message (DBusConnection *connection,
                                         DBusMessage    *message)
{
  DBusList *link;

  link = _dbus_list_alloc_link (message);
  if (link == NULL)
    return FALSE;

  dbus_message_ref (message);
  _dbus_connection_queue_received_message_link (connection, link);

  return TRUE;
}
#endif

/**
 * Adds a message-containing list link to the incoming message queue,
 * taking ownership of the link and the message's current refcount.
 * Cannot fail due to lack of memory.
 *
 * @param connection the connection.
 * @param link the message link to queue.
 */
void
_dbus_connection_queue_received_message_link (DBusConnection  *connection,
                                              DBusList        *link)
{
  DBusPendingCall *pending;
  dbus_int32_t reply_serial;
  DBusMessage *message;
  
  _dbus_assert (_dbus_transport_get_is_authenticated (connection->transport));
  
  _dbus_list_append_link (&connection->incoming_messages,
                          link);
  message = link->data;

  /* If this is a reply we're waiting on, remove timeout for it */
  reply_serial = dbus_message_get_reply_serial (message);
  if (reply_serial != -1)
    {
      pending = _dbus_hash_table_lookup_int (connection->pending_replies,
                                             reply_serial);
      if (pending != NULL)
	{
	  if (pending->timeout_added)
	    _dbus_connection_remove_timeout (connection,
                                             pending->timeout);

	  pending->timeout_added = FALSE;
	}
    }
  
  connection->n_incoming += 1;

  _dbus_connection_wakeup_mainloop (connection);
  
  _dbus_verbose ("Message %p (%d %s %s %s '%s' reply to %u) added to incoming queue %p, %d incoming\n",
                 message,
                 dbus_message_get_type (message),
		 dbus_message_get_path (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message),
                 dbus_message_get_reply_serial (message),
                 connection,
                 connection->n_incoming);
}

/**
 * Adds a link + message to the incoming message queue.
 * Can't fail. Takes ownership of both link and message.
 *
 * @param connection the connection.
 * @param link the list node and message to queue.
 *
 * @todo This needs to wake up the mainloop if it is in
 * a poll/select and this is a multithreaded app.
 */
static void
_dbus_connection_queue_synthesized_message_link (DBusConnection *connection,
						 DBusList *link)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_list_append_link (&connection->incoming_messages, link);

  connection->n_incoming += 1;

  _dbus_connection_wakeup_mainloop (connection);
  
  _dbus_verbose ("Synthesized message %p added to incoming queue %p, %d incoming\n",
                 link->data, connection, connection->n_incoming);
}


/**
 * Checks whether there are messages in the outgoing message queue.
 * Called with connection lock held.
 *
 * @param connection the connection.
 * @returns #TRUE if the outgoing queue is non-empty.
 */
dbus_bool_t
_dbus_connection_has_messages_to_send_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  return connection->outgoing_messages != NULL;
}

/**
 * Checks whether there are messages in the outgoing message queue.
 *
 * @param connection the connection.
 * @returns #TRUE if the outgoing queue is non-empty.
 */
dbus_bool_t
dbus_connection_has_messages_to_send (DBusConnection *connection)
{
  dbus_bool_t v;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);

  CONNECTION_LOCK (connection);
  v = _dbus_connection_has_messages_to_send_unlocked (connection);
  CONNECTION_UNLOCK (connection);

  return v;
}

/**
 * Gets the next outgoing message. The message remains in the
 * queue, and the caller does not own a reference to it.
 *
 * @param connection the connection.
 * @returns the message to be sent.
 */ 
DBusMessage*
_dbus_connection_get_message_to_send (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  return _dbus_list_get_last (&connection->outgoing_messages);
}

/**
 * Notifies the connection that a message has been sent, so the
 * message can be removed from the outgoing queue.
 * Called with the connection lock held.
 *
 * @param connection the connection.
 * @param message the message that was sent.
 */
void
_dbus_connection_message_sent (DBusConnection *connection,
                               DBusMessage    *message)
{
  DBusList *link;

  HAVE_LOCK_CHECK (connection);
  
  /* This can be called before we even complete authentication, since
   * it's called on disconnect to clean up the outgoing queue.
   * It's also called as we successfully send each message.
   */
  
  link = _dbus_list_get_last_link (&connection->outgoing_messages);
  _dbus_assert (link != NULL);
  _dbus_assert (link->data == message);

  /* Save this link in the link cache */
  _dbus_list_unlink (&connection->outgoing_messages,
                     link);
  _dbus_list_prepend_link (&connection->link_cache, link);
  
  connection->n_outgoing -= 1;

  _dbus_verbose ("Message %p (%d %s %s %s '%s') removed from outgoing queue %p, %d left to send\n",
                 message,
                 dbus_message_get_type (message),
		 dbus_message_get_path (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message),
                 connection, connection->n_outgoing);

  /* Save this link in the link cache also */
  _dbus_message_remove_size_counter (message, connection->outgoing_counter,
                                     &link);
  _dbus_list_prepend_link (&connection->link_cache, link);
  
  dbus_message_unref (message);
}

typedef dbus_bool_t (* DBusWatchAddFunction)     (DBusWatchList *list,
                                                  DBusWatch     *watch);
typedef void        (* DBusWatchRemoveFunction)  (DBusWatchList *list,
                                                  DBusWatch     *watch);
typedef void        (* DBusWatchToggleFunction)  (DBusWatchList *list,
                                                  DBusWatch     *watch,
                                                  dbus_bool_t    enabled);

static dbus_bool_t
protected_change_watch (DBusConnection         *connection,
                        DBusWatch              *watch,
                        DBusWatchAddFunction    add_function,
                        DBusWatchRemoveFunction remove_function,
                        DBusWatchToggleFunction toggle_function,
                        dbus_bool_t             enabled)
{
  DBusWatchList *watches;
  dbus_bool_t retval;
  
  HAVE_LOCK_CHECK (connection);

  /* This isn't really safe or reasonable; a better pattern is the "do everything, then
   * drop lock and call out" one; but it has to be propagated up through all callers
   */
  
  watches = connection->watches;
  if (watches)
    {
      connection->watches = NULL;
      _dbus_connection_ref_unlocked (connection);
      CONNECTION_UNLOCK (connection);

      if (add_function)
        retval = (* add_function) (watches, watch);
      else if (remove_function)
        {
          retval = TRUE;
          (* remove_function) (watches, watch);
        }
      else
        {
          retval = TRUE;
          (* toggle_function) (watches, watch, enabled);
        }
      
      CONNECTION_LOCK (connection);
      connection->watches = watches;
      _dbus_connection_unref_unlocked (connection);

      return retval;
    }
  else
    return FALSE;
}
     

/**
 * Adds a watch using the connection's DBusAddWatchFunction if
 * available. Otherwise records the watch to be added when said
 * function is available. Also re-adds the watch if the
 * DBusAddWatchFunction changes. May fail due to lack of memory.
 *
 * @param connection the connection.
 * @param watch the watch to add.
 * @returns #TRUE on success.
 */
dbus_bool_t
_dbus_connection_add_watch (DBusConnection *connection,
                            DBusWatch      *watch)
{
  return protected_change_watch (connection, watch,
                                 _dbus_watch_list_add_watch,
                                 NULL, NULL, FALSE);
}

/**
 * Removes a watch using the connection's DBusRemoveWatchFunction
 * if available. It's an error to call this function on a watch
 * that was not previously added.
 *
 * @param connection the connection.
 * @param watch the watch to remove.
 */
void
_dbus_connection_remove_watch (DBusConnection *connection,
                               DBusWatch      *watch)
{
  protected_change_watch (connection, watch,
                          NULL,
                          _dbus_watch_list_remove_watch,
                          NULL, FALSE);
}

/**
 * Toggles a watch and notifies app via connection's
 * DBusWatchToggledFunction if available. It's an error to call this
 * function on a watch that was not previously added.
 * Connection lock should be held when calling this.
 *
 * @param connection the connection.
 * @param watch the watch to toggle.
 * @param enabled whether to enable or disable
 */
void
_dbus_connection_toggle_watch (DBusConnection *connection,
                               DBusWatch      *watch,
                               dbus_bool_t     enabled)
{
  _dbus_assert (watch != NULL);

  protected_change_watch (connection, watch,
                          NULL, NULL,
                          _dbus_watch_list_toggle_watch,
                          enabled);
}

typedef dbus_bool_t (* DBusTimeoutAddFunction)    (DBusTimeoutList *list,
                                                   DBusTimeout     *timeout);
typedef void        (* DBusTimeoutRemoveFunction) (DBusTimeoutList *list,
                                                   DBusTimeout     *timeout);
typedef void        (* DBusTimeoutToggleFunction) (DBusTimeoutList *list,
                                                   DBusTimeout     *timeout,
                                                   dbus_bool_t      enabled);

static dbus_bool_t
protected_change_timeout (DBusConnection           *connection,
                          DBusTimeout              *timeout,
                          DBusTimeoutAddFunction    add_function,
                          DBusTimeoutRemoveFunction remove_function,
                          DBusTimeoutToggleFunction toggle_function,
                          dbus_bool_t               enabled)
{
  DBusTimeoutList *timeouts;
  dbus_bool_t retval;
  
  HAVE_LOCK_CHECK (connection);

  /* This isn't really safe or reasonable; a better pattern is the "do everything, then
   * drop lock and call out" one; but it has to be propagated up through all callers
   */
  
  timeouts = connection->timeouts;
  if (timeouts)
    {
      connection->timeouts = NULL;
      _dbus_connection_ref_unlocked (connection);
      CONNECTION_UNLOCK (connection);

      if (add_function)
        retval = (* add_function) (timeouts, timeout);
      else if (remove_function)
        {
          retval = TRUE;
          (* remove_function) (timeouts, timeout);
        }
      else
        {
          retval = TRUE;
          (* toggle_function) (timeouts, timeout, enabled);
        }
      
      CONNECTION_LOCK (connection);
      connection->timeouts = timeouts;
      _dbus_connection_unref_unlocked (connection);

      return retval;
    }
  else
    return FALSE;
}

/**
 * Adds a timeout using the connection's DBusAddTimeoutFunction if
 * available. Otherwise records the timeout to be added when said
 * function is available. Also re-adds the timeout if the
 * DBusAddTimeoutFunction changes. May fail due to lack of memory.
 * The timeout will fire repeatedly until removed.
 *
 * @param connection the connection.
 * @param timeout the timeout to add.
 * @returns #TRUE on success.
 */
dbus_bool_t
_dbus_connection_add_timeout (DBusConnection *connection,
			      DBusTimeout    *timeout)
{
  return protected_change_timeout (connection, timeout,
                                   _dbus_timeout_list_add_timeout,
                                   NULL, NULL, FALSE);
}

/**
 * Removes a timeout using the connection's DBusRemoveTimeoutFunction
 * if available. It's an error to call this function on a timeout
 * that was not previously added.
 *
 * @param connection the connection.
 * @param timeout the timeout to remove.
 */
void
_dbus_connection_remove_timeout (DBusConnection *connection,
				 DBusTimeout    *timeout)
{
  protected_change_timeout (connection, timeout,
                            NULL,
                            _dbus_timeout_list_remove_timeout,
                            NULL, FALSE);
}

/**
 * Toggles a timeout and notifies app via connection's
 * DBusTimeoutToggledFunction if available. It's an error to call this
 * function on a timeout that was not previously added.
 *
 * @param connection the connection.
 * @param timeout the timeout to toggle.
 * @param enabled whether to enable or disable
 */
void
_dbus_connection_toggle_timeout (DBusConnection   *connection,
                                 DBusTimeout      *timeout,
                                 dbus_bool_t       enabled)
{
  protected_change_timeout (connection, timeout,
                            NULL, NULL,
                            _dbus_timeout_list_toggle_timeout,
                            enabled);
}

static dbus_bool_t
_dbus_connection_attach_pending_call_unlocked (DBusConnection  *connection,
                                               DBusPendingCall *pending)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (pending->reply_serial != 0);

  if (!_dbus_connection_add_timeout (connection, pending->timeout))
    return FALSE;
  
  if (!_dbus_hash_table_insert_int (connection->pending_replies,
                                    pending->reply_serial,
                                    pending))
    {
      _dbus_connection_remove_timeout (connection, pending->timeout);

      HAVE_LOCK_CHECK (connection);
      return FALSE;
    }
  
  pending->timeout_added = TRUE;
  pending->connection = connection;

  dbus_pending_call_ref (pending);

  HAVE_LOCK_CHECK (connection);
  
  return TRUE;
}

static void
free_pending_call_on_hash_removal (void *data)
{
  DBusPendingCall *pending;
  
  if (data == NULL)
    return;

  pending = data;

  if (pending->connection)
    {
      if (pending->timeout_added)
        {
          _dbus_connection_remove_timeout (pending->connection,
                                           pending->timeout);
          pending->timeout_added = FALSE;
        }

      pending->connection = NULL;
      
      dbus_pending_call_unref (pending);
    }
}

static void
_dbus_connection_detach_pending_call_unlocked (DBusConnection  *connection,
                                               DBusPendingCall *pending)
{
  /* Can't have a destroy notifier on the pending call if we're going to do this */

  dbus_pending_call_ref (pending);
  _dbus_hash_table_remove_int (connection->pending_replies,
                               pending->reply_serial);
  _dbus_assert (pending->connection == NULL);
  dbus_pending_call_unref (pending);
}

static void
_dbus_connection_detach_pending_call_and_unlock (DBusConnection  *connection,
                                                 DBusPendingCall *pending)
{
  /* The idea here is to avoid finalizing the pending call
   * with the lock held, since there's a destroy notifier
   * in pending call that goes out to application code.
   */
  dbus_pending_call_ref (pending);
  _dbus_hash_table_remove_int (connection->pending_replies,
                               pending->reply_serial);
  _dbus_assert (pending->connection == NULL);
  CONNECTION_UNLOCK (connection);
  dbus_pending_call_unref (pending);
}

/**
 * Removes a pending call from the connection, such that
 * the pending reply will be ignored. May drop the last
 * reference to the pending call.
 *
 * @param connection the connection
 * @param pending the pending call
 */
void
_dbus_connection_remove_pending_call (DBusConnection  *connection,
                                      DBusPendingCall *pending)
{
  CONNECTION_LOCK (connection);
  _dbus_connection_detach_pending_call_and_unlock (connection, pending);
}

/**
 * Completes a pending call with the given message,
 * or if the message is #NULL, by timing out the pending call.
 * 
 * @param pending the pending call
 * @param message the message to complete the call with, or #NULL
 *  to time out the call
 */
void
_dbus_pending_call_complete_and_unlock (DBusPendingCall *pending,
                                        DBusMessage     *message)
{
  if (message == NULL)
    {
      message = pending->timeout_link->data;
      _dbus_list_clear (&pending->timeout_link);
    }
  else
    dbus_message_ref (message);

  _dbus_verbose ("  handing message %p (%s) to pending call serial %u\n",
                 message,
                 dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_METHOD_RETURN ?
                 "method return" :
                 dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_ERROR ?
                 "error" : "other type",
                 pending->reply_serial);
  
  _dbus_assert (pending->reply == NULL);
  _dbus_assert (pending->reply_serial == dbus_message_get_reply_serial (message));
  pending->reply = message;
  
  dbus_pending_call_ref (pending); /* in case there's no app with a ref held */
  _dbus_connection_detach_pending_call_and_unlock (pending->connection, pending);
  
  /* Must be called unlocked since it invokes app callback */
  _dbus_pending_call_notify (pending);
  dbus_pending_call_unref (pending);
}

/**
 * Acquire the transporter I/O path. This must be done before
 * doing any I/O in the transporter. May sleep and drop the
 * IO path mutex while waiting for the I/O path.
 *
 * @param connection the connection.
 * @param timeout_milliseconds maximum blocking time, or -1 for no limit.
 * @returns TRUE if the I/O path was acquired.
 */
static dbus_bool_t
_dbus_connection_acquire_io_path (DBusConnection *connection,
				  int timeout_milliseconds)
{
  dbus_bool_t we_acquired;
  
  HAVE_LOCK_CHECK (connection);

  /* We don't want the connection to vanish */
  _dbus_connection_ref_unlocked (connection);

  /* We will only touch io_path_acquired which is protected by our mutex */
  CONNECTION_UNLOCK (connection);
  
  _dbus_verbose ("%s locking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->io_path_mutex);

  _dbus_verbose ("%s start connection->io_path_acquired = %d timeout = %d\n",
                 _DBUS_FUNCTION_NAME, connection->io_path_acquired, timeout_milliseconds);

  we_acquired = FALSE;
  
  if (connection->io_path_acquired)
    {
      if (timeout_milliseconds != -1)
        {
          _dbus_verbose ("%s waiting %d for IO path to be acquirable\n",
                         _DBUS_FUNCTION_NAME, timeout_milliseconds);
          _dbus_condvar_wait_timeout (connection->io_path_cond,
                                      connection->io_path_mutex,
                                      timeout_milliseconds);
        }
      else
        {
          while (connection->io_path_acquired)
            {
              _dbus_verbose ("%s waiting for IO path to be acquirable\n", _DBUS_FUNCTION_NAME);
              _dbus_condvar_wait (connection->io_path_cond, connection->io_path_mutex);
            }
        }
    }
  
  if (!connection->io_path_acquired)
    {
      we_acquired = TRUE;
      connection->io_path_acquired = TRUE;
    }
  
  _dbus_verbose ("%s end connection->io_path_acquired = %d we_acquired = %d\n",
                 _DBUS_FUNCTION_NAME, connection->io_path_acquired, we_acquired);

  _dbus_verbose ("%s unlocking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->io_path_mutex);

  CONNECTION_LOCK (connection);
  
  HAVE_LOCK_CHECK (connection);

  _dbus_connection_unref_unlocked (connection);
  
  return we_acquired;
}

/**
 * Release the I/O path when you're done with it. Only call
 * after you've acquired the I/O. Wakes up at most one thread
 * currently waiting to acquire the I/O path.
 *
 * @param connection the connection.
 */
static void
_dbus_connection_release_io_path (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_verbose ("%s locking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->io_path_mutex);
  
  _dbus_assert (connection->io_path_acquired);

  _dbus_verbose ("%s start connection->io_path_acquired = %d\n",
                 _DBUS_FUNCTION_NAME, connection->io_path_acquired);
  
  connection->io_path_acquired = FALSE;
  _dbus_condvar_wake_one (connection->io_path_cond);

  _dbus_verbose ("%s unlocking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->io_path_mutex);
}

/**
 * Queues incoming messages and sends outgoing messages for this
 * connection, optionally blocking in the process. Each call to
 * _dbus_connection_do_iteration_unlocked() will call select() or poll() one
 * time and then read or write data if possible.
 *
 * The purpose of this function is to be able to flush outgoing
 * messages or queue up incoming messages without returning
 * control to the application and causing reentrancy weirdness.
 *
 * The flags parameter allows you to specify whether to
 * read incoming messages, write outgoing messages, or both,
 * and whether to block if no immediate action is possible.
 *
 * The timeout_milliseconds parameter does nothing unless the
 * iteration is blocking.
 *
 * If there are no outgoing messages and DBUS_ITERATION_DO_READING
 * wasn't specified, then it's impossible to block, even if
 * you specify DBUS_ITERATION_BLOCK; in that case the function
 * returns immediately.
 *
 * Called with connection lock held.
 * 
 * @param connection the connection.
 * @param flags iteration flags.
 * @param timeout_milliseconds maximum blocking time, or -1 for no limit.
 */
void
_dbus_connection_do_iteration_unlocked (DBusConnection *connection,
                                        unsigned int    flags,
                                        int             timeout_milliseconds)
{
  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  HAVE_LOCK_CHECK (connection);
  
  if (connection->n_outgoing == 0)
    flags &= ~DBUS_ITERATION_DO_WRITING;

  if (_dbus_connection_acquire_io_path (connection,
					(flags & DBUS_ITERATION_BLOCK) ? timeout_milliseconds : 0))
    {
      HAVE_LOCK_CHECK (connection);
      
      _dbus_transport_do_iteration (connection->transport,
				    flags, timeout_milliseconds);
      _dbus_connection_release_io_path (connection);
    }

  HAVE_LOCK_CHECK (connection);

  _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
}

/**
 * Creates a new connection for the given transport.  A transport
 * represents a message stream that uses some concrete mechanism, such
 * as UNIX domain sockets. May return #NULL if insufficient
 * memory exists to create the connection.
 *
 * @param transport the transport.
 * @returns the new connection, or #NULL on failure.
 */
DBusConnection*
_dbus_connection_new_for_transport (DBusTransport *transport)
{
  DBusConnection *connection;
  DBusWatchList *watch_list;
  DBusTimeoutList *timeout_list;
  DBusHashTable *pending_replies;
  DBusMutex *mutex;
  DBusMutex *io_path_mutex;
  DBusMutex *dispatch_mutex;
  DBusCondVar *message_returned_cond;
  DBusCondVar *dispatch_cond;
  DBusCondVar *io_path_cond;
  DBusList *disconnect_link;
  DBusMessage *disconnect_message;
  DBusCounter *outgoing_counter;
  DBusObjectTree *objects;
  
  watch_list = NULL;
  connection = NULL;
  pending_replies = NULL;
  timeout_list = NULL;
  mutex = NULL;
  io_path_mutex = NULL;
  dispatch_mutex = NULL;
  message_returned_cond = NULL;
  dispatch_cond = NULL;
  io_path_cond = NULL;
  disconnect_link = NULL;
  disconnect_message = NULL;
  outgoing_counter = NULL;
  objects = NULL;
  
  watch_list = _dbus_watch_list_new ();
  if (watch_list == NULL)
    goto error;

  timeout_list = _dbus_timeout_list_new ();
  if (timeout_list == NULL)
    goto error;  

  pending_replies =
    _dbus_hash_table_new (DBUS_HASH_INT,
			  NULL,
                          (DBusFreeFunction)free_pending_call_on_hash_removal);
  if (pending_replies == NULL)
    goto error;
  
  connection = dbus_new0 (DBusConnection, 1);
  if (connection == NULL)
    goto error;

  mutex = _dbus_mutex_new ();
  if (mutex == NULL)
    goto error;

  io_path_mutex = _dbus_mutex_new ();
  if (io_path_mutex == NULL)
    goto error;

  dispatch_mutex = _dbus_mutex_new ();
  if (dispatch_mutex == NULL)
    goto error;
  
  message_returned_cond = _dbus_condvar_new ();
  if (message_returned_cond == NULL)
    goto error;
  
  dispatch_cond = _dbus_condvar_new ();
  if (dispatch_cond == NULL)
    goto error;
  
  io_path_cond = _dbus_condvar_new ();
  if (io_path_cond == NULL)
    goto error;

  disconnect_message = dbus_message_new_signal (DBUS_PATH_LOCAL,
                                                DBUS_INTERFACE_LOCAL,
                                                "Disconnected");
  
  if (disconnect_message == NULL)
    goto error;

  disconnect_link = _dbus_list_alloc_link (disconnect_message);
  if (disconnect_link == NULL)
    goto error;

  outgoing_counter = _dbus_counter_new ();
  if (outgoing_counter == NULL)
    goto error;

  objects = _dbus_object_tree_new (connection);
  if (objects == NULL)
    goto error;
  
  if (_dbus_modify_sigpipe)
    _dbus_disable_sigpipe ();
  
  connection->refcount.value = 1;
  connection->mutex = mutex;
  connection->dispatch_cond = dispatch_cond;
  connection->dispatch_mutex = dispatch_mutex;
  connection->io_path_cond = io_path_cond;
  connection->io_path_mutex = io_path_mutex;
  connection->transport = transport;
  connection->watches = watch_list;
  connection->timeouts = timeout_list;
  connection->pending_replies = pending_replies;
  connection->outgoing_counter = outgoing_counter;
  connection->filter_list = NULL;
  connection->last_dispatch_status = DBUS_DISPATCH_COMPLETE; /* so we're notified first time there's data */
  connection->objects = objects;
  connection->exit_on_disconnect = FALSE;
  connection->shareable = FALSE;
#ifndef DBUS_DISABLE_CHECKS
  connection->generation = _dbus_current_generation;
#endif
  
  _dbus_data_slot_list_init (&connection->slot_list);

  connection->client_serial = 1;

  connection->disconnect_message_link = disconnect_link;

  CONNECTION_LOCK (connection);
  
  if (!_dbus_transport_set_connection (transport, connection))
    goto error;

  _dbus_transport_ref (transport);

  CONNECTION_UNLOCK (connection);
  
  return connection;
  
 error:
  if (disconnect_message != NULL)
    dbus_message_unref (disconnect_message);
  
  if (disconnect_link != NULL)
    _dbus_list_free_link (disconnect_link);
  
  if (io_path_cond != NULL)
    _dbus_condvar_free (io_path_cond);
  
  if (dispatch_cond != NULL)
    _dbus_condvar_free (dispatch_cond);
  
  if (message_returned_cond != NULL)
    _dbus_condvar_free (message_returned_cond);
  
  if (mutex != NULL)
    _dbus_mutex_free (mutex);

  if (io_path_mutex != NULL)
    _dbus_mutex_free (io_path_mutex);

  if (dispatch_mutex != NULL)
    _dbus_mutex_free (dispatch_mutex);
  
  if (connection != NULL)
    dbus_free (connection);

  if (pending_replies)
    _dbus_hash_table_unref (pending_replies);
  
  if (watch_list)
    _dbus_watch_list_free (watch_list);

  if (timeout_list)
    _dbus_timeout_list_free (timeout_list);

  if (outgoing_counter)
    _dbus_counter_unref (outgoing_counter);

  if (objects)
    _dbus_object_tree_unref (objects);
  
  return NULL;
}

/**
 * Increments the reference count of a DBusConnection.
 * Requires that the caller already holds the connection lock.
 *
 * @param connection the connection.
 * @returns the connection.
 */
DBusConnection *
_dbus_connection_ref_unlocked (DBusConnection *connection)
{  
  _dbus_assert (connection != NULL);
  _dbus_assert (connection->generation == _dbus_current_generation);

  HAVE_LOCK_CHECK (connection);
  
#ifdef DBUS_HAVE_ATOMIC_INT
  _dbus_atomic_inc (&connection->refcount);
#else
  _dbus_assert (connection->refcount.value > 0);
  connection->refcount.value += 1;
#endif

  return connection;
}

/**
 * Decrements the reference count of a DBusConnection.
 * Requires that the caller already holds the connection lock.
 *
 * @param connection the connection.
 */
void
_dbus_connection_unref_unlocked (DBusConnection *connection)
{
  dbus_bool_t last_unref;

  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (connection != NULL);

  /* The connection lock is better than the global
   * lock in the atomic increment fallback
   */
  
#ifdef DBUS_HAVE_ATOMIC_INT
  last_unref = (_dbus_atomic_dec (&connection->refcount) == 1);
#else
  _dbus_assert (connection->refcount.value > 0);

  connection->refcount.value -= 1;
  last_unref = (connection->refcount.value == 0);  
#if 0
  printf ("unref_unlocked() connection %p count = %d\n", connection, connection->refcount.value);
#endif
#endif
  
  if (last_unref)
    _dbus_connection_last_unref (connection);
}

static dbus_uint32_t
_dbus_connection_get_next_client_serial (DBusConnection *connection)
{
  int serial;

  serial = connection->client_serial++;

  if (connection->client_serial < 0)
    connection->client_serial = 1;
  
  return serial;
}

/**
 * A callback for use with dbus_watch_new() to create a DBusWatch.
 * 
 * @todo This is basically a hack - we could delete _dbus_transport_handle_watch()
 * and the virtual handle_watch in DBusTransport if we got rid of it.
 * The reason this is some work is threading, see the _dbus_connection_handle_watch()
 * implementation.
 *
 * @param watch the watch.
 * @param condition the current condition of the file descriptors being watched.
 * @param data must be a pointer to a #DBusConnection
 * @returns #FALSE if the IO condition may not have been fully handled due to lack of memory
 */
dbus_bool_t
_dbus_connection_handle_watch (DBusWatch                   *watch,
                               unsigned int                 condition,
                               void                        *data)
{
  DBusConnection *connection;
  dbus_bool_t retval;
  DBusDispatchStatus status;

  connection = data;

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  CONNECTION_LOCK (connection);
  _dbus_connection_acquire_io_path (connection, -1);
  HAVE_LOCK_CHECK (connection);
  retval = _dbus_transport_handle_watch (connection->transport,
                                         watch, condition);

  _dbus_connection_release_io_path (connection);

  HAVE_LOCK_CHECK (connection);

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);

  _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
  
  return retval;
}

_DBUS_DEFINE_GLOBAL_LOCK (shared_connections);
static DBusHashTable *shared_connections = NULL;

static void
shared_connections_shutdown (void *data)
{
  _DBUS_LOCK (shared_connections);

  _dbus_assert (_dbus_hash_table_get_n_entries (shared_connections) == 0);
  _dbus_hash_table_unref (shared_connections);
  shared_connections = NULL;
  
  _DBUS_UNLOCK (shared_connections);
}

static dbus_bool_t
connection_lookup_shared (DBusAddressEntry  *entry,
                          DBusConnection   **result)
{
  _dbus_verbose ("checking for existing connection\n");
  
  *result = NULL;
  
  _DBUS_LOCK (shared_connections);

  if (shared_connections == NULL)
    {
      _dbus_verbose ("creating shared_connections hash table\n");
      
      shared_connections = _dbus_hash_table_new (DBUS_HASH_STRING,
                                                 dbus_free,
                                                 NULL);
      if (shared_connections == NULL)
        {
          _DBUS_UNLOCK (shared_connections);
          return FALSE;
        }

      if (!_dbus_register_shutdown_func (shared_connections_shutdown, NULL))
        {
          _dbus_hash_table_unref (shared_connections);
          shared_connections = NULL;
          _DBUS_UNLOCK (shared_connections);
          return FALSE;
        }

      _dbus_verbose ("  successfully created shared_connections\n");
      
      _DBUS_UNLOCK (shared_connections);
      return TRUE; /* no point looking up in the hash we just made */
    }
  else
    {
      const char *guid;

      guid = dbus_address_entry_get_value (entry, "guid");
      
      if (guid != NULL)
        {
          *result = _dbus_hash_table_lookup_string (shared_connections,
                                                    guid);

          if (*result)
            {
              /* The DBusConnection can't have been disconnected
               * between the lookup and this code, because the
               * disconnection will take the shared_connections lock to
               * remove the connection. It can't have been finalized
               * since you have to disconnect prior to finalize.
               *
               * Thus it's safe to ref the connection.
               */
              dbus_connection_ref (*result);

              _dbus_verbose ("looked up existing connection to server guid %s\n",
                             guid);
            }
        }
      
      _DBUS_UNLOCK (shared_connections);
      return TRUE;
    }
}

static dbus_bool_t
connection_record_shared_unlocked (DBusConnection *connection,
                                   const char     *guid)
{
  char *guid_key;
  char *guid_in_connection;

  /* A separate copy of the key is required in the hash table, because
   * we don't have a lock on the connection when we are doing a hash
   * lookup.
   */
  
  _dbus_assert (connection->server_guid == NULL);
  _dbus_assert (connection->shareable);
  
  guid_key = _dbus_strdup (guid);
  if (guid_key == NULL)
    return FALSE;

  guid_in_connection = _dbus_strdup (guid);
  if (guid_in_connection == NULL)
    {
      dbus_free (guid_key);
      return FALSE;
    }
  
  _DBUS_LOCK (shared_connections);
  _dbus_assert (shared_connections != NULL);
  
  if (!_dbus_hash_table_insert_string (shared_connections,
                                       guid_key, connection))
    {
      dbus_free (guid_key);
      dbus_free (guid_in_connection);
      _DBUS_UNLOCK (shared_connections);
      return FALSE;
    }

  connection->server_guid = guid_in_connection;

  _dbus_verbose ("stored connection to %s to be shared\n",
                 connection->server_guid);
  
  _DBUS_UNLOCK (shared_connections);

  _dbus_assert (connection->server_guid != NULL);
  
  return TRUE;
}

static void
connection_forget_shared_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  if (connection->server_guid == NULL)
    return;

  _dbus_verbose ("dropping connection to %s out of the shared table\n",
                 connection->server_guid);
  
  _DBUS_LOCK (shared_connections);

  if (!_dbus_hash_table_remove_string (shared_connections,
                                       connection->server_guid))
    _dbus_assert_not_reached ("connection was not in the shared table");
  
  dbus_free (connection->server_guid);
  connection->server_guid = NULL;

  _DBUS_UNLOCK (shared_connections);
}

static DBusConnection*
connection_try_from_address_entry (DBusAddressEntry *entry,
                                   DBusError        *error)
{
  DBusTransport *transport;
  DBusConnection *connection;

  transport = _dbus_transport_open (entry, error);

  if (transport == NULL)
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      return NULL;
    }

  connection = _dbus_connection_new_for_transport (transport);

  _dbus_transport_unref (transport);
  
  if (connection == NULL)
    {
      _DBUS_SET_OOM (error);
      return NULL;
    }

#ifndef DBUS_DISABLE_CHECKS
  _dbus_assert (!connection->have_connection_lock);
#endif
  return connection;
}

/*
 * If the shared parameter is true, then any existing connection will
 * be used (and if a new connection is created, it will be available
 * for use by others). If the shared parameter is false, a new
 * connection will always be created, and the new connection will
 * never be returned to other callers.
 *
 * @param address the address
 * @param shared whether the connection is shared or private
 * @param error error return
 * @returns the connection or #NULL on error
 */
static DBusConnection*
_dbus_connection_open_internal (const char     *address,
                                dbus_bool_t     shared,
                                DBusError      *error)
{
  DBusConnection *connection;
  DBusAddressEntry **entries;
  DBusError tmp_error;
  DBusError first_error;
  int len, i;

  _DBUS_ASSERT_ERROR_IS_CLEAR (error);

  _dbus_verbose ("opening %s connection to: %s\n",
                 shared ? "shared" : "private", address);
  
  if (!dbus_parse_address (address, &entries, &len, error))
    return NULL;

  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  
  connection = NULL;

  dbus_error_init (&tmp_error);
  dbus_error_init (&first_error);
  for (i = 0; i < len; i++)
    {
      if (shared)
        {
          if (!connection_lookup_shared (entries[i], &connection))
            _DBUS_SET_OOM (&tmp_error);
        }

      if (connection == NULL)
        {
          connection = connection_try_from_address_entry (entries[i],
                                                          &tmp_error);
          
          if (connection != NULL && shared)
            {
              const char *guid;

              connection->shareable = TRUE;
              
              guid = dbus_address_entry_get_value (entries[i], "guid");

              /* we don't have a connection lock but we know nobody
               * else has a handle to the connection
               */
              
              if (guid &&
                  !connection_record_shared_unlocked (connection, guid))
                {
                  _DBUS_SET_OOM (&tmp_error);
                  dbus_connection_disconnect (connection);
                  dbus_connection_unref (connection);
                  connection = NULL;
                }

              /* but as of now the connection is possibly shared
               * since another thread could have pulled it from the table
               */
            }
        }
      
      if (connection)
	break;

      _DBUS_ASSERT_ERROR_IS_SET (&tmp_error);
      
      if (i == 0)
        dbus_move_error (&tmp_error, &first_error);
      else
        dbus_error_free (&tmp_error);
    }

  /* NOTE we don't have a lock on a possibly-shared connection object */
  
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  _DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
  
  if (connection == NULL)
    {
      _DBUS_ASSERT_ERROR_IS_SET (&first_error);
      dbus_move_error (&first_error, error);
    }
  else
    {
      dbus_error_free (&first_error);
    }
  
  dbus_address_entries_free (entries);
  return connection;
}

/** @} */

/**
 * @addtogroup DBusConnection
 *
 * @{
 */

/**
 * Gets a connection to a remote address. If a connection to the given
 * address already exists, returns the existing connection with its
 * reference count incremented.  Otherwise, returns a new connection
 * and saves the new connection for possible re-use if a future call
 * to dbus_connection_open() asks to connect to the same server.
 *
 * Use dbus_connection_open_private() to get a dedicated connection
 * not shared with other callers of dbus_connection_open().
 *
 * If the open fails, the function returns #NULL, and provides a
 * reason for the failure in the error parameter. Pass #NULL for the
 * error parameter if you aren't interested in the reason for
 * failure.
 * 
 * @param address the address.
 * @param error address where an error can be returned.
 * @returns new connection, or #NULL on failure.
 */
DBusConnection*
dbus_connection_open (const char     *address,
                      DBusError      *error)
{
  DBusConnection *connection;

  _dbus_return_val_if_fail (address != NULL, NULL);
  _dbus_return_val_if_error_is_set (error, NULL);

  connection = _dbus_connection_open_internal (address,
                                               TRUE,
                                               error);

  return connection;
}

/**
 * Opens a new, dedicated connection to a remote address. Unlike
 * dbus_connection_open(), always creates a new connection.
 * This connection will not be saved or recycled by libdbus.
 *
 * If the open fails, the function returns #NULL, and provides a
 * reason for the failure in the error parameter. Pass #NULL for the
 * error parameter if you aren't interested in the reason for
 * failure.
 * 
 * @param address the address.
 * @param error address where an error can be returned.
 * @returns new connection, or #NULL on failure.
 */
DBusConnection*
dbus_connection_open_private (const char     *address,
                              DBusError      *error)
{
  DBusConnection *connection;

  _dbus_return_val_if_fail (address != NULL, NULL);
  _dbus_return_val_if_error_is_set (error, NULL);

  connection = _dbus_connection_open_internal (address,
                                               FALSE,
                                               error);

  return connection;
}

/**
 * Increments the reference count of a DBusConnection.
 *
 * @param connection the connection.
 * @returns the connection.
 */
DBusConnection *
dbus_connection_ref (DBusConnection *connection)
{
  _dbus_return_val_if_fail (connection != NULL, NULL);
  _dbus_return_val_if_fail (connection->generation == _dbus_current_generation, NULL);
  
  /* The connection lock is better than the global
   * lock in the atomic increment fallback
   */
  
#ifdef DBUS_HAVE_ATOMIC_INT
  _dbus_atomic_inc (&connection->refcount);
#else
  CONNECTION_LOCK (connection);
  _dbus_assert (connection->refcount.value > 0);

  connection->refcount.value += 1;
  CONNECTION_UNLOCK (connection);
#endif

  return connection;
}

static void
free_outgoing_message (void *element,
                       void *data)
{
  DBusMessage *message = element;
  DBusConnection *connection = data;

  _dbus_message_remove_size_counter (message,
                                     connection->outgoing_counter,
                                     NULL);
  dbus_message_unref (message);
}

/* This is run without the mutex held, but after the last reference
 * to the connection has been dropped we should have no thread-related
 * problems
 */
static void
_dbus_connection_last_unref (DBusConnection *connection)
{
  DBusList *link;

  _dbus_verbose ("Finalizing connection %p\n", connection);
  
  _dbus_assert (connection->refcount.value == 0);
  
  /* You have to disconnect the connection before unref:ing it. Otherwise
   * you won't get the disconnected message.
   */
  _dbus_assert (!_dbus_transport_get_is_connected (connection->transport));
  _dbus_assert (connection->server_guid == NULL);
  
  /* ---- We're going to call various application callbacks here, hope it doesn't break anything... */
  _dbus_object_tree_free_all_unlocked (connection->objects);
  
  dbus_connection_set_dispatch_status_function (connection, NULL, NULL, NULL);
  dbus_connection_set_wakeup_main_function (connection, NULL, NULL, NULL);
  dbus_connection_set_unix_user_function (connection, NULL, NULL, NULL);
  
  _dbus_watch_list_free (connection->watches);
  connection->watches = NULL;
  
  _dbus_timeout_list_free (connection->timeouts);
  connection->timeouts = NULL;

  _dbus_data_slot_list_free (&connection->slot_list);
  
  link = _dbus_list_get_first_link (&connection->filter_list);
  while (link != NULL)
    {
      DBusMessageFilter *filter = link->data;
      DBusList *next = _dbus_list_get_next_link (&connection->filter_list, link);

      filter->function = NULL;
      _dbus_message_filter_unref (filter); /* calls app callback */
      link->data = NULL;
      
      link = next;
    }
  _dbus_list_clear (&connection->filter_list);
  
  /* ---- Done with stuff that invokes application callbacks */

  _dbus_object_tree_unref (connection->objects);  

  _dbus_hash_table_unref (connection->pending_replies);
  connection->pending_replies = NULL;
  
  _dbus_list_clear (&connection->filter_list);
  
  _dbus_list_foreach (&connection->outgoing_messages,
                      free_outgoing_message,
		      connection);
  _dbus_list_clear (&connection->outgoing_messages);
  
  _dbus_list_foreach (&connection->incoming_messages,
		      (DBusForeachFunction) dbus_message_unref,
		      NULL);
  _dbus_list_clear (&connection->incoming_messages);

  _dbus_counter_unref (connection->outgoing_counter);

  _dbus_transport_unref (connection->transport);

  if (connection->disconnect_message_link)
    {
      DBusMessage *message = connection->disconnect_message_link->data;
      dbus_message_unref (message);
      _dbus_list_free_link (connection->disconnect_message_link);
    }

  _dbus_list_clear (&connection->link_cache);
  
  _dbus_condvar_free (connection->dispatch_cond);
  _dbus_condvar_free (connection->io_path_cond);

  _dbus_mutex_free (connection->io_path_mutex);
  _dbus_mutex_free (connection->dispatch_mutex);

  _dbus_mutex_free (connection->mutex);
  
  dbus_free (connection);
}

/**
 * Decrements the reference count of a DBusConnection, and finalizes
 * it if the count reaches zero.  It is a bug to drop the last reference
 * to a connection that has not been disconnected.
 *
 * @todo in practice it can be quite tricky to never unref a connection
 * that's still connected; maybe there's some way we could avoid
 * the requirement.
 *
 * @param connection the connection.
 */
void
dbus_connection_unref (DBusConnection *connection)
{
  dbus_bool_t last_unref;

  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (connection->generation == _dbus_current_generation);
  
  /* The connection lock is better than the global
   * lock in the atomic increment fallback
   */
  
#ifdef DBUS_HAVE_ATOMIC_INT
  last_unref = (_dbus_atomic_dec (&connection->refcount) == 1);
#else
  CONNECTION_LOCK (connection);
  
  _dbus_assert (connection->refcount.value > 0);

  connection->refcount.value -= 1;
  last_unref = (connection->refcount.value == 0);

#if 0
  printf ("unref() connection %p count = %d\n", connection, connection->refcount.value);
#endif
  
  CONNECTION_UNLOCK (connection);
#endif
  
  if (last_unref)
    _dbus_connection_last_unref (connection);
}

/**
 * Closes the connection, so no further data can be sent or received.
 * Any further attempts to send data will result in errors.  This
 * function does not affect the connection's reference count.  It's
 * safe to disconnect a connection more than once; all calls after the
 * first do nothing. It's impossible to "reconnect" a connection, a
 * new connection must be created. This function may result in a call
 * to the DBusDispatchStatusFunction set with
 * dbus_connection_set_dispatch_status_function(), as the disconnect
 * message it generates needs to be dispatched.
 *
 * @param connection the connection.
 */
void
dbus_connection_disconnect (DBusConnection *connection)
{
  DBusDispatchStatus status;
  
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (connection->generation == _dbus_current_generation);

  _dbus_verbose ("Disconnecting %p\n", connection);
  
  CONNECTION_LOCK (connection);
  
  _dbus_transport_disconnect (connection->transport);

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
}

static dbus_bool_t
_dbus_connection_get_is_connected_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  return _dbus_transport_get_is_connected (connection->transport);
}

/**
 * Gets whether the connection is currently connected.  All
 * connections are connected when they are opened.  A connection may
 * become disconnected when the remote application closes its end, or
 * exits; a connection may also be disconnected with
 * dbus_connection_disconnect().
 *
 * @param connection the connection.
 * @returns #TRUE if the connection is still alive.
 */
dbus_bool_t
dbus_connection_get_is_connected (DBusConnection *connection)
{
  dbus_bool_t res;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);
  res = _dbus_connection_get_is_connected_unlocked (connection);
  CONNECTION_UNLOCK (connection);
  
  return res;
}

/**
 * Gets whether the connection was authenticated. (Note that
 * if the connection was authenticated then disconnected,
 * this function still returns #TRUE)
 *
 * @param connection the connection
 * @returns #TRUE if the connection was ever authenticated
 */
dbus_bool_t
dbus_connection_get_is_authenticated (DBusConnection *connection)
{
  dbus_bool_t res;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);
  res = _dbus_transport_get_is_authenticated (connection->transport);
  CONNECTION_UNLOCK (connection);
  
  return res;
}

/**
 * Set whether _exit() should be called when the connection receives a
 * disconnect signal. The call to _exit() comes after any handlers for
 * the disconnect signal run; handlers can cancel the exit by calling
 * this function.
 *
 * By default, exit_on_disconnect is #FALSE; but for message bus
 * connections returned from dbus_bus_get() it will be toggled on
 * by default.
 *
 * @param connection the connection
 * @param exit_on_disconnect #TRUE if _exit() should be called after a disconnect signal
 */
void
dbus_connection_set_exit_on_disconnect (DBusConnection *connection,
                                        dbus_bool_t     exit_on_disconnect)
{
  _dbus_return_if_fail (connection != NULL);

  CONNECTION_LOCK (connection);
  connection->exit_on_disconnect = exit_on_disconnect != FALSE;
  CONNECTION_UNLOCK (connection);
}

static DBusPreallocatedSend*
_dbus_connection_preallocate_send_unlocked (DBusConnection *connection)
{
  DBusPreallocatedSend *preallocated;

  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (connection != NULL);
  
  preallocated = dbus_new (DBusPreallocatedSend, 1);
  if (preallocated == NULL)
    return NULL;

  if (connection->link_cache != NULL)
    {
      preallocated->queue_link =
        _dbus_list_pop_first_link (&connection->link_cache);
      preallocated->queue_link->data = NULL;
    }
  else
    {
      preallocated->queue_link = _dbus_list_alloc_link (NULL);
      if (preallocated->queue_link == NULL)
        goto failed_0;
    }
  
  if (connection->link_cache != NULL)
    {
      preallocated->counter_link =
        _dbus_list_pop_first_link (&connection->link_cache);
      preallocated->counter_link->data = connection->outgoing_counter;
    }
  else
    {
      preallocated->counter_link = _dbus_list_alloc_link (connection->outgoing_counter);
      if (preallocated->counter_link == NULL)
        goto failed_1;
    }

  _dbus_counter_ref (preallocated->counter_link->data);

  preallocated->connection = connection;
  
  return preallocated;
  
 failed_1:
  _dbus_list_free_link (preallocated->queue_link);
 failed_0:
  dbus_free (preallocated);
  
  return NULL;
}

/**
 * Preallocates resources needed to send a message, allowing the message 
 * to be sent without the possibility of memory allocation failure.
 * Allows apps to create a future guarantee that they can send
 * a message regardless of memory shortages.
 *
 * @param connection the connection we're preallocating for.
 * @returns the preallocated resources, or #NULL
 */
DBusPreallocatedSend*
dbus_connection_preallocate_send (DBusConnection *connection)
{
  DBusPreallocatedSend *preallocated;

  _dbus_return_val_if_fail (connection != NULL, NULL);

  CONNECTION_LOCK (connection);
  
  preallocated =
    _dbus_connection_preallocate_send_unlocked (connection);

  CONNECTION_UNLOCK (connection);

  return preallocated;
}

/**
 * Frees preallocated message-sending resources from
 * dbus_connection_preallocate_send(). Should only
 * be called if the preallocated resources are not used
 * to send a message.
 *
 * @param connection the connection
 * @param preallocated the resources
 */
void
dbus_connection_free_preallocated_send (DBusConnection       *connection,
                                        DBusPreallocatedSend *preallocated)
{
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (preallocated != NULL);  
  _dbus_return_if_fail (connection == preallocated->connection);

  _dbus_list_free_link (preallocated->queue_link);
  _dbus_counter_unref (preallocated->counter_link->data);
  _dbus_list_free_link (preallocated->counter_link);
  dbus_free (preallocated);
}

/* Called with lock held, does not update dispatch status */
static void
_dbus_connection_send_preallocated_unlocked_no_update (DBusConnection       *connection,
                                                       DBusPreallocatedSend *preallocated,
                                                       DBusMessage          *message,
                                                       dbus_uint32_t        *client_serial)
{
  dbus_uint32_t serial;
  const char *sig;

  preallocated->queue_link->data = message;
  _dbus_list_prepend_link (&connection->outgoing_messages,
                           preallocated->queue_link);

  _dbus_message_add_size_counter_link (message,
                                       preallocated->counter_link);

  dbus_free (preallocated);
  preallocated = NULL;
  
  dbus_message_ref (message);
  
  connection->n_outgoing += 1;

  sig = dbus_message_get_signature (message);
  
  _dbus_verbose ("Message %p (%d %s %s %s '%s') for %s added to outgoing queue %p, %d pending to send\n",
                 message,
                 dbus_message_get_type (message),
		 dbus_message_get_path (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 sig,
                 dbus_message_get_destination (message) ?
                 dbus_message_get_destination (message) :
                 "null",
                 connection,
                 connection->n_outgoing);

  if (dbus_message_get_serial (message) == 0)
    {
      serial = _dbus_connection_get_next_client_serial (connection);
      _dbus_message_set_serial (message, serial);
      if (client_serial)
        *client_serial = serial;
    }
  else
    {
      if (client_serial)
        *client_serial = dbus_message_get_serial (message);
    }

  _dbus_verbose ("Message %p serial is %u\n",
                 message, dbus_message_get_serial (message));
  
  _dbus_message_lock (message);

  /* Now we need to run an iteration to hopefully just write the messages
   * out immediately, and otherwise get them queued up
   */
  _dbus_connection_do_iteration_unlocked (connection,
                                          DBUS_ITERATION_DO_WRITING,
                                          -1);

  /* If stuff is still queued up, be sure we wake up the main loop */
  if (connection->n_outgoing > 0)
    _dbus_connection_wakeup_mainloop (connection);
}

static void
_dbus_connection_send_preallocated_and_unlock (DBusConnection       *connection,
					       DBusPreallocatedSend *preallocated,
					       DBusMessage          *message,
					       dbus_uint32_t        *client_serial)
{
  DBusDispatchStatus status;

  HAVE_LOCK_CHECK (connection);
  
  _dbus_connection_send_preallocated_unlocked_no_update (connection,
                                                         preallocated,
                                                         message, client_serial);

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
}

/**
 * Sends a message using preallocated resources. This function cannot fail.
 * It works identically to dbus_connection_send() in other respects.
 * Preallocated resources comes from dbus_connection_preallocate_send().
 * This function "consumes" the preallocated resources, they need not
 * be freed separately.
 *
 * @param connection the connection
 * @param preallocated the preallocated resources
 * @param message the message to send
 * @param client_serial return location for client serial assigned to the message
 */
void
dbus_connection_send_preallocated (DBusConnection       *connection,
                                   DBusPreallocatedSend *preallocated,
                                   DBusMessage          *message,
                                   dbus_uint32_t        *client_serial)
{
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (preallocated != NULL);
  _dbus_return_if_fail (message != NULL);
  _dbus_return_if_fail (preallocated->connection == connection);
  _dbus_return_if_fail (dbus_message_get_type (message) != DBUS_MESSAGE_TYPE_METHOD_CALL ||
                        (dbus_message_get_interface (message) != NULL &&
                         dbus_message_get_member (message) != NULL));
  _dbus_return_if_fail (dbus_message_get_type (message) != DBUS_MESSAGE_TYPE_SIGNAL ||
                        (dbus_message_get_interface (message) != NULL &&
                         dbus_message_get_member (message) != NULL));
  
  CONNECTION_LOCK (connection);
  _dbus_connection_send_preallocated_and_unlock (connection,
						 preallocated,
						 message, client_serial);
}

static dbus_bool_t
_dbus_connection_send_unlocked_no_update (DBusConnection *connection,
                                          DBusMessage    *message,
                                          dbus_uint32_t  *client_serial)
{
  DBusPreallocatedSend *preallocated;

  _dbus_assert (connection != NULL);
  _dbus_assert (message != NULL);
  
  preallocated = _dbus_connection_preallocate_send_unlocked (connection);
  if (preallocated == NULL)
    return FALSE;

  _dbus_connection_send_preallocated_unlocked_no_update (connection,
                                                         preallocated,
                                                         message,
                                                         client_serial);
  return TRUE;
}

dbus_bool_t
_dbus_connection_send_and_unlock (DBusConnection *connection,
				  DBusMessage    *message,
				  dbus_uint32_t  *client_serial)
{
  DBusPreallocatedSend *preallocated;

  _dbus_assert (connection != NULL);
  _dbus_assert (message != NULL);
  
  preallocated = _dbus_connection_preallocate_send_unlocked (connection);
  if (preallocated == NULL)
    {
      CONNECTION_UNLOCK (connection);
      return FALSE;
    }

  _dbus_connection_send_preallocated_and_unlock (connection,
						 preallocated,
						 message,
						 client_serial);
  return TRUE;
}

/**
 * Adds a message to the outgoing message queue. Does not block to
 * write the message to the network; that happens asynchronously. To
 * force the message to be written, call dbus_connection_flush().
 * Because this only queues the message, the only reason it can
 * fail is lack of memory. Even if the connection is disconnected,
 * no error will be returned.
 *
 * If the function fails due to lack of memory, it returns #FALSE.
 * The function will never fail for other reasons; even if the
 * connection is disconnected, you can queue an outgoing message,
 * though obviously it won't be sent.
 * 
 * @param connection the connection.
 * @param message the message to write.
 * @param client_serial return location for client serial.
 * @returns #TRUE on success.
 */
dbus_bool_t
dbus_connection_send (DBusConnection *connection,
                      DBusMessage    *message,
                      dbus_uint32_t  *client_serial)
{
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (message != NULL, FALSE);

  CONNECTION_LOCK (connection);

  return _dbus_connection_send_and_unlock (connection,
					   message,
					   client_serial);
}

static dbus_bool_t
reply_handler_timeout (void *data)
{
  DBusConnection *connection;
  DBusDispatchStatus status;
  DBusPendingCall *pending = data;

  connection = pending->connection;
  
  CONNECTION_LOCK (connection);
  if (pending->timeout_link)
    {
      _dbus_connection_queue_synthesized_message_link (connection,
						       pending->timeout_link);
      pending->timeout_link = NULL;
    }

  _dbus_connection_remove_timeout (connection,
				   pending->timeout);
  pending->timeout_added = FALSE;

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* Unlocks, and calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
  
  return TRUE;
}

/**
 * Queues a message to send, as with dbus_connection_send_message(),
 * but also returns a #DBusPendingCall used to receive a reply to the
 * message. If no reply is received in the given timeout_milliseconds,
 * this function expires the pending reply and generates a synthetic
 * error reply (generated in-process, not by the remote application)
 * indicating that a timeout occurred.
 *
 * A #DBusPendingCall will see a reply message after any filters, but
 * before any object instances or other handlers. A #DBusPendingCall
 * will always see exactly one reply message, unless it's cancelled
 * with dbus_pending_call_cancel().
 * 
 * If a filter filters out the reply before the handler sees it, the
 * reply is immediately timed out and a timeout error reply is
 * generated. If a filter removes the timeout error reply then the
 * #DBusPendingCall will get confused. Filtering the timeout error
 * is thus considered a bug and will print a warning.
 * 
 * If #NULL is passed for the pending_return, the #DBusPendingCall
 * will still be generated internally, and used to track
 * the message reply timeout. This means a timeout error will
 * occur if no reply arrives, unlike with dbus_connection_send().
 *
 * If -1 is passed for the timeout, a sane default timeout is used. -1
 * is typically the best value for the timeout for this reason, unless
 * you want a very short or very long timeout.  There is no way to
 * avoid a timeout entirely, other than passing INT_MAX for the
 * timeout to postpone it indefinitely.
 * 
 * @param connection the connection
 * @param message the message to send
 * @param pending_return return location for a #DBusPendingCall object, or #NULL
 * @param timeout_milliseconds timeout in milliseconds or -1 for default
 * @returns #TRUE if the message is successfully queued, #FALSE if no memory.
 *
 */
dbus_bool_t
dbus_connection_send_with_reply (DBusConnection     *connection,
                                 DBusMessage        *message,
                                 DBusPendingCall   **pending_return,
                                 int                 timeout_milliseconds)
{
  DBusPendingCall *pending;
  DBusMessage *reply;
  DBusList *reply_link;
  dbus_int32_t serial = -1;
  DBusDispatchStatus status;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (message != NULL, FALSE);
  _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, FALSE);

  if (pending_return)
    *pending_return = NULL;
  
  pending = _dbus_pending_call_new (connection,
                                    timeout_milliseconds,
                                    reply_handler_timeout);

  if (pending == NULL)
    return FALSE;

  CONNECTION_LOCK (connection);
  
  /* Assign a serial to the message */
  if (dbus_message_get_serial (message) == 0)
    {
      serial = _dbus_connection_get_next_client_serial (connection);
      _dbus_message_set_serial (message, serial);
    }

  pending->reply_serial = serial;

  reply = dbus_message_new_error (message, DBUS_ERROR_NO_REPLY,
                                  "No reply within specified time");
  if (reply == NULL)
    goto error;

  reply_link = _dbus_list_alloc_link (reply);
  if (reply_link == NULL)
    {
      CONNECTION_UNLOCK (connection);
      dbus_message_unref (reply);
      goto error_unlocked;
    }

  pending->timeout_link = reply_link;

  /* Insert the serial in the pending replies hash;
   * hash takes a refcount on DBusPendingCall.
   * Also, add the timeout.
   */
  if (!_dbus_connection_attach_pending_call_unlocked (connection,
						      pending))
    goto error;
 
  if (!_dbus_connection_send_unlocked_no_update (connection, message, NULL))
    {
      _dbus_connection_detach_pending_call_and_unlock (connection,
						       pending);
      goto error_unlocked;
    }

  if (pending_return)
    *pending_return = pending;
  else
    {
      _dbus_connection_detach_pending_call_unlocked (connection, pending);
      dbus_pending_call_unref (pending);
    }

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);

  return TRUE;

 error:
  CONNECTION_UNLOCK (connection);
 error_unlocked:
  dbus_pending_call_unref (pending);
  return FALSE;
}

/* This is slightly strange since we can pop a message here without
 * the dispatch lock.
 */
static DBusMessage*
check_for_reply_unlocked (DBusConnection *connection,
                          dbus_uint32_t   client_serial)
{
  DBusList *link;

  HAVE_LOCK_CHECK (connection);
  
  link = _dbus_list_get_first_link (&connection->incoming_messages);

  while (link != NULL)
    {
      DBusMessage *reply = link->data;

      if (dbus_message_get_reply_serial (reply) == client_serial)
	{
	  _dbus_list_remove_link (&connection->incoming_messages, link);
	  connection->n_incoming  -= 1;
	  return reply;
	}
      link = _dbus_list_get_next_link (&connection->incoming_messages, link);
    }

  return NULL;
}

/**
 * Blocks until a pending call times out or gets a reply.
 *
 * Does not re-enter the main loop or run filter/path-registered
 * callbacks. The reply to the message will not be seen by
 * filter callbacks.
 *
 * Returns immediately if pending call already got a reply.
 * 
 * @todo could use performance improvements (it keeps scanning
 * the whole message queue for example)
 *
 * @param pending the pending call we block for a reply on
 */
void
_dbus_connection_block_pending_call (DBusPendingCall *pending)
{
  long start_tv_sec, start_tv_usec;
  long end_tv_sec, end_tv_usec;
  long tv_sec, tv_usec;
  DBusDispatchStatus status;
  DBusConnection *connection;
  dbus_uint32_t client_serial;
  int timeout_milliseconds;

  _dbus_assert (pending != NULL);

  if (dbus_pending_call_get_completed (pending))
    return;

  if (pending->connection == NULL)
    return; /* call already detached */

  dbus_pending_call_ref (pending); /* necessary because the call could be canceled */
  
  connection = pending->connection;
  client_serial = pending->reply_serial;

  /* note that timeout_milliseconds is limited to a smallish value
   * in _dbus_pending_call_new() so overflows aren't possible
   * below
   */
  timeout_milliseconds = dbus_timeout_get_interval (pending->timeout);

  /* Flush message queue */
  dbus_connection_flush (connection);

  CONNECTION_LOCK (connection);

  _dbus_get_current_time (&start_tv_sec, &start_tv_usec);
  end_tv_sec = start_tv_sec + timeout_milliseconds / 1000;
  end_tv_usec = start_tv_usec + (timeout_milliseconds % 1000) * 1000;
  end_tv_sec += end_tv_usec / _DBUS_USEC_PER_SECOND;
  end_tv_usec = end_tv_usec % _DBUS_USEC_PER_SECOND;

  _dbus_verbose ("dbus_connection_send_with_reply_and_block(): will block %d milliseconds for reply serial %u from %ld sec %ld usec to %ld sec %ld usec\n",
                 timeout_milliseconds,
                 client_serial,
                 start_tv_sec, start_tv_usec,
                 end_tv_sec, end_tv_usec);

  /* Now we wait... */
  /* always block at least once as we know we don't have the reply yet */
  _dbus_connection_do_iteration_unlocked (connection,
                                          DBUS_ITERATION_DO_READING |
                                          DBUS_ITERATION_BLOCK,
                                          timeout_milliseconds);

 recheck_status:

  _dbus_verbose ("%s top of recheck\n", _DBUS_FUNCTION_NAME);
  
  HAVE_LOCK_CHECK (connection);
  
  /* queue messages and get status */

  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* the get_completed() is in case a dispatch() while we were blocking
   * got the reply instead of us.
   */
  if (dbus_pending_call_get_completed (pending))
    {
      _dbus_verbose ("Pending call completed by dispatch in %s\n", _DBUS_FUNCTION_NAME);
      _dbus_connection_update_dispatch_status_and_unlock (connection, status);
      dbus_pending_call_unref (pending);
      return;
    }
  
  if (status == DBUS_DISPATCH_DATA_REMAINS)
    {
      DBusMessage *reply;
      
      reply = check_for_reply_unlocked (connection, client_serial);
      if (reply != NULL)
        {
          _dbus_verbose ("%s checked for reply\n", _DBUS_FUNCTION_NAME);

          _dbus_verbose ("dbus_connection_send_with_reply_and_block(): got reply\n");
          
          _dbus_pending_call_complete_and_unlock (pending, reply);
          dbus_message_unref (reply);

          CONNECTION_LOCK (connection);
          status = _dbus_connection_get_dispatch_status_unlocked (connection);
          _dbus_connection_update_dispatch_status_and_unlock (connection, status);
          dbus_pending_call_unref (pending);
          
          return;
        }
    }
  
  _dbus_get_current_time (&tv_sec, &tv_usec);
  
  if (!_dbus_connection_get_is_connected_unlocked (connection))
    {
      /* FIXME send a "DBUS_ERROR_DISCONNECTED" instead, just to help
       * programmers understand what went wrong since the timeout is
       * confusing
       */
      
      _dbus_pending_call_complete_and_unlock (pending, NULL);
      dbus_pending_call_unref (pending);
      return;
    }
  else if (tv_sec < start_tv_sec)
    _dbus_verbose ("dbus_connection_send_with_reply_and_block(): clock set backward\n");
  else if (connection->disconnect_message_link == NULL)
    _dbus_verbose ("dbus_connection_send_with_reply_and_block(): disconnected\n");
  else if (tv_sec < end_tv_sec ||
           (tv_sec == end_tv_sec && tv_usec < end_tv_usec))
    {
      timeout_milliseconds = (end_tv_sec - tv_sec) * 1000 +
        (end_tv_usec - tv_usec) / 1000;
      _dbus_verbose ("dbus_connection_send_with_reply_and_block(): %d milliseconds remain\n", timeout_milliseconds);
      _dbus_assert (timeout_milliseconds >= 0);
      
      if (status == DBUS_DISPATCH_NEED_MEMORY)
        {
          /* Try sleeping a bit, as we aren't sure we need to block for reading,
           * we may already have a reply in the buffer and just can't process
           * it.
           */
          _dbus_verbose ("dbus_connection_send_with_reply_and_block() waiting for more memory\n");
          
          if (timeout_milliseconds < 100)
            ; /* just busy loop */
          else if (timeout_milliseconds <= 1000)
            _dbus_sleep_milliseconds (timeout_milliseconds / 3);
          else
            _dbus_sleep_milliseconds (1000);
        }
      else
        {          
          /* block again, we don't have the reply buffered yet. */
          _dbus_connection_do_iteration_unlocked (connection,
                                                  DBUS_ITERATION_DO_READING |
                                                  DBUS_ITERATION_BLOCK,
                                                  timeout_milliseconds);
        }

      goto recheck_status;
    }

  _dbus_verbose ("dbus_connection_send_with_reply_and_block(): Waited %ld milliseconds and got no reply\n",
                 (tv_sec - start_tv_sec) * 1000 + (tv_usec - start_tv_usec) / 1000);

  _dbus_assert (!dbus_pending_call_get_completed (pending));
  
  /* unlock and call user code */
  _dbus_pending_call_complete_and_unlock (pending, NULL);

  /* update user code on dispatch status */
  CONNECTION_LOCK (connection);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
  dbus_pending_call_unref (pending);
}

/**
 * Sends a message and blocks a certain time period while waiting for
 * a reply.  This function does not reenter the main loop,
 * i.e. messages other than the reply are queued up but not
 * processed. This function is used to do non-reentrant "method
 * calls."
 * 
 * If a normal reply is received, it is returned, and removed from the
 * incoming message queue. If it is not received, #NULL is returned
 * and the error is set to #DBUS_ERROR_NO_REPLY.  If an error reply is
 * received, it is converted to a #DBusError and returned as an error,
 * then the reply message is deleted. If something else goes wrong,
 * result is set to whatever is appropriate, such as
 * #DBUS_ERROR_NO_MEMORY or #DBUS_ERROR_DISCONNECTED.
 *
 * @param connection the connection
 * @param message the message to send
 * @param timeout_milliseconds timeout in milliseconds or -1 for default
 * @param error return location for error message
 * @returns the message that is the reply or #NULL with an error code if the
 * function fails.
 */
DBusMessage*
dbus_connection_send_with_reply_and_block (DBusConnection     *connection,
                                           DBusMessage        *message,
                                           int                 timeout_milliseconds,
                                           DBusError          *error)
{
  DBusMessage *reply;
  DBusPendingCall *pending;
  
  _dbus_return_val_if_fail (connection != NULL, NULL);
  _dbus_return_val_if_fail (message != NULL, NULL);
  _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, FALSE);  
  _dbus_return_val_if_error_is_set (error, NULL);
  
  if (!dbus_connection_send_with_reply (connection, message,
                                        &pending, timeout_milliseconds))
    {
      _DBUS_SET_OOM (error);
      return NULL;
    }

  _dbus_assert (pending != NULL);
  
  dbus_pending_call_block (pending);

  reply = dbus_pending_call_steal_reply (pending);
  dbus_pending_call_unref (pending);

  /* call_complete_and_unlock() called from pending_call_block() should
   * always fill this in.
   */
  _dbus_assert (reply != NULL);
  
   if (dbus_set_error_from_message (error, reply))
    {
      dbus_message_unref (reply);
      return NULL;
    }
  else
    return reply;
}

/**
 * Blocks until the outgoing message queue is empty.
 *
 * @param connection the connection.
 */
void
dbus_connection_flush (DBusConnection *connection)
{
  /* We have to specify DBUS_ITERATION_DO_READING here because
   * otherwise we could have two apps deadlock if they are both doing
   * a flush(), and the kernel buffers fill up. This could change the
   * dispatch status.
   */
  DBusDispatchStatus status;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  while (connection->n_outgoing > 0 &&
         _dbus_connection_get_is_connected_unlocked (connection))
    {
      _dbus_verbose ("doing iteration in %s\n", _DBUS_FUNCTION_NAME);
      HAVE_LOCK_CHECK (connection);
      _dbus_connection_do_iteration_unlocked (connection,
                                              DBUS_ITERATION_DO_READING |
                                              DBUS_ITERATION_DO_WRITING |
                                              DBUS_ITERATION_BLOCK,
                                              -1);
    }

  HAVE_LOCK_CHECK (connection);
  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  HAVE_LOCK_CHECK (connection);
  /* Unlocks and calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);

  _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
}

/**
 * Returns the first-received message from the incoming message queue,
 * leaving it in the queue. If the queue is empty, returns #NULL.
 * 
 * The caller does not own a reference to the returned message, and
 * must either return it using dbus_connection_return_message() or
 * keep it after calling dbus_connection_steal_borrowed_message(). No
 * one can get at the message while its borrowed, so return it as
 * quickly as possible and don't keep a reference to it after
 * returning it. If you need to keep the message, make a copy of it.
 *
 * dbus_connection_dispatch() will block if called while a borrowed
 * message is outstanding; only one piece of code can be playing with
 * the incoming queue at a time. This function will block if called
 * during a dbus_connection_dispatch().
 *
 * @param connection the connection.
 * @returns next message in the incoming queue.
 */
DBusMessage*
dbus_connection_borrow_message (DBusConnection *connection)
{
  DBusDispatchStatus status;
  DBusMessage *message;

  _dbus_return_val_if_fail (connection != NULL, NULL);

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  /* this is called for the side effect that it queues
   * up any messages from the transport
   */
  status = dbus_connection_get_dispatch_status (connection);
  if (status != DBUS_DISPATCH_DATA_REMAINS)
    return NULL;
  
  CONNECTION_LOCK (connection);

  _dbus_connection_acquire_dispatch (connection);

  /* While a message is outstanding, the dispatch lock is held */
  _dbus_assert (connection->message_borrowed == NULL);

  connection->message_borrowed = _dbus_list_get_first (&connection->incoming_messages);
  
  message = connection->message_borrowed;

  /* Note that we KEEP the dispatch lock until the message is returned */
  if (message == NULL)
    _dbus_connection_release_dispatch (connection);

  CONNECTION_UNLOCK (connection);
  
  return message;
}

/**
 * Used to return a message after peeking at it using
 * dbus_connection_borrow_message(). Only called if
 * message from dbus_connection_borrow_message() was non-#NULL.
 *
 * @param connection the connection
 * @param message the message from dbus_connection_borrow_message()
 */
void
dbus_connection_return_message (DBusConnection *connection,
				DBusMessage    *message)
{
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (message != NULL);
  _dbus_return_if_fail (message == connection->message_borrowed);
  _dbus_return_if_fail (connection->dispatch_acquired);
  
  CONNECTION_LOCK (connection);
  
  _dbus_assert (message == connection->message_borrowed);
  
  connection->message_borrowed = NULL;

  _dbus_connection_release_dispatch (connection);
  
  CONNECTION_UNLOCK (connection);
}

/**
 * Used to keep a message after peeking at it using
 * dbus_connection_borrow_message(). Before using this function, see
 * the caveats/warnings in the documentation for
 * dbus_connection_pop_message().
 *
 * @param connection the connection
 * @param message the message from dbus_connection_borrow_message()
 */
void
dbus_connection_steal_borrowed_message (DBusConnection *connection,
					DBusMessage    *message)
{
  DBusMessage *pop_message;

  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (message != NULL);
  _dbus_return_if_fail (message == connection->message_borrowed);
  _dbus_return_if_fail (connection->dispatch_acquired);
  
  CONNECTION_LOCK (connection);
 
  _dbus_assert (message == connection->message_borrowed);

  pop_message = _dbus_list_pop_first (&connection->incoming_messages);
  _dbus_assert (message == pop_message);
  
  connection->n_incoming -= 1;
 
  _dbus_verbose ("Incoming message %p stolen from queue, %d incoming\n",
		 message, connection->n_incoming);
 
  connection->message_borrowed = NULL;

  _dbus_connection_release_dispatch (connection);
  
  CONNECTION_UNLOCK (connection);
}

/* See dbus_connection_pop_message, but requires the caller to own
 * the lock before calling. May drop the lock while running.
 */
static DBusList*
_dbus_connection_pop_message_link_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (connection->message_borrowed == NULL);
  
  if (connection->n_incoming > 0)
    {
      DBusList *link;

      link = _dbus_list_pop_first_link (&connection->incoming_messages);
      connection->n_incoming -= 1;

      _dbus_verbose ("Message %p (%d %s %s %s '%s') removed from incoming queue %p, %d incoming\n",
                     link->data,
                     dbus_message_get_type (link->data),
		     dbus_message_get_path (link->data), 
                     dbus_message_get_interface (link->data) ?
                     dbus_message_get_interface (link->data) :
                     "no interface",
                     dbus_message_get_member (link->data) ?
                     dbus_message_get_member (link->data) :
                     "no member",
                     dbus_message_get_signature (link->data),
                     connection, connection->n_incoming);

      return link;
    }
  else
    return NULL;
}

/* See dbus_connection_pop_message, but requires the caller to own
 * the lock before calling. May drop the lock while running.
 */
static DBusMessage*
_dbus_connection_pop_message_unlocked (DBusConnection *connection)
{
  DBusList *link;

  HAVE_LOCK_CHECK (connection);
  
  link = _dbus_connection_pop_message_link_unlocked (connection);

  if (link != NULL)
    {
      DBusMessage *message;
      
      message = link->data;
      
      _dbus_list_free_link (link);
      
      return message;
    }
  else
    return NULL;
}

static void
_dbus_connection_putback_message_link_unlocked (DBusConnection *connection,
                                                DBusList       *message_link)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (message_link != NULL);
  /* You can't borrow a message while a link is outstanding */
  _dbus_assert (connection->message_borrowed == NULL);
  /* We had to have the dispatch lock across the pop/putback */
  _dbus_assert (connection->dispatch_acquired);

  _dbus_list_prepend_link (&connection->incoming_messages,
                           message_link);
  connection->n_incoming += 1;

  _dbus_verbose ("Message %p (%d %s %s '%s') put back into queue %p, %d incoming\n",
                 message_link->data,
                 dbus_message_get_type (message_link->data),
                 dbus_message_get_interface (message_link->data) ?
                 dbus_message_get_interface (message_link->data) :
                 "no interface",
                 dbus_message_get_member (message_link->data) ?
                 dbus_message_get_member (message_link->data) :
                 "no member",
                 dbus_message_get_signature (message_link->data),
                 connection, connection->n_incoming);
}

/**
 * Returns the first-received message from the incoming message queue,
 * removing it from the queue. The caller owns a reference to the
 * returned message. If the queue is empty, returns #NULL.
 *
 * This function bypasses any message handlers that are registered,
 * and so using it is usually wrong. Instead, let the main loop invoke
 * dbus_connection_dispatch(). Popping messages manually is only
 * useful in very simple programs that don't share a #DBusConnection
 * with any libraries or other modules.
 *
 * There is a lock that covers all ways of accessing the incoming message
 * queue, so dbus_connection_dispatch(), dbus_connection_pop_message(),
 * dbus_connection_borrow_message(), etc. will all block while one of the others
 * in the group is running.
 * 
 * @param connection the connection.
 * @returns next message in the incoming queue.
 */
DBusMessage*
dbus_connection_pop_message (DBusConnection *connection)
{
  DBusMessage *message;
  DBusDispatchStatus status;

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  /* this is called for the side effect that it queues
   * up any messages from the transport
   */
  status = dbus_connection_get_dispatch_status (connection);
  if (status != DBUS_DISPATCH_DATA_REMAINS)
    return NULL;
  
  CONNECTION_LOCK (connection);
  _dbus_connection_acquire_dispatch (connection);
  HAVE_LOCK_CHECK (connection);
  
  message = _dbus_connection_pop_message_unlocked (connection);

  _dbus_verbose ("Returning popped message %p\n", message);    

  _dbus_connection_release_dispatch (connection);
  CONNECTION_UNLOCK (connection);
  
  return message;
}

/**
 * Acquire the dispatcher. This is a separate lock so the main
 * connection lock can be dropped to call out to application dispatch
 * handlers.
 *
 * @param connection the connection.
 */
static void
_dbus_connection_acquire_dispatch (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);

  _dbus_connection_ref_unlocked (connection);
  CONNECTION_UNLOCK (connection);
  
  _dbus_verbose ("%s locking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->dispatch_mutex);

  while (connection->dispatch_acquired)
    {
      _dbus_verbose ("%s waiting for dispatch to be acquirable\n", _DBUS_FUNCTION_NAME);
      _dbus_condvar_wait (connection->dispatch_cond, connection->dispatch_mutex);
    }
  
  _dbus_assert (!connection->dispatch_acquired);

  connection->dispatch_acquired = TRUE;

  _dbus_verbose ("%s unlocking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->dispatch_mutex);
  
  CONNECTION_LOCK (connection);
  _dbus_connection_unref_unlocked (connection);
}

/**
 * Release the dispatcher when you're done with it. Only call
 * after you've acquired the dispatcher. Wakes up at most one
 * thread currently waiting to acquire the dispatcher.
 *
 * @param connection the connection.
 */
static void
_dbus_connection_release_dispatch (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_verbose ("%s locking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->dispatch_mutex);
  
  _dbus_assert (connection->dispatch_acquired);

  connection->dispatch_acquired = FALSE;
  _dbus_condvar_wake_one (connection->dispatch_cond);

  _dbus_verbose ("%s unlocking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->dispatch_mutex);
}

static void
_dbus_connection_failed_pop (DBusConnection *connection,
			     DBusList       *message_link)
{
  _dbus_list_prepend_link (&connection->incoming_messages,
			   message_link);
  connection->n_incoming += 1;
}

static DBusDispatchStatus
_dbus_connection_get_dispatch_status_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  if (connection->n_incoming > 0)
    return DBUS_DISPATCH_DATA_REMAINS;
  else if (!_dbus_transport_queue_messages (connection->transport))
    return DBUS_DISPATCH_NEED_MEMORY;
  else
    {
      DBusDispatchStatus status;
      dbus_bool_t is_connected;
      
      status = _dbus_transport_get_dispatch_status (connection->transport);
      is_connected = _dbus_transport_get_is_connected (connection->transport);

      _dbus_verbose ("dispatch status = %s is_connected = %d\n",
                     DISPATCH_STATUS_NAME (status), is_connected);
      
      if (!is_connected)
        {
          if (status == DBUS_DISPATCH_COMPLETE &&
              connection->disconnect_message_link)
            {
              _dbus_verbose ("Sending disconnect message from %s\n",
                             _DBUS_FUNCTION_NAME);

              connection_forget_shared_unlocked (connection);
              
              /* We haven't sent the disconnect message already,
               * and all real messages have been queued up.
               */
              _dbus_connection_queue_synthesized_message_link (connection,
                                                               connection->disconnect_message_link);
              connection->disconnect_message_link = NULL;
            }

          /* Dump the outgoing queue, we aren't going to be able to
           * send it now, and we'd like accessors like
           * dbus_connection_get_outgoing_size() to be accurate.
           */
          if (connection->n_outgoing > 0)
            {
              DBusList *link;
              
              _dbus_verbose ("Dropping %d outgoing messages since we're disconnected\n",
                             connection->n_outgoing);
              
              while ((link = _dbus_list_get_last_link (&connection->outgoing_messages)))
                {
                  _dbus_connection_message_sent (connection, link->data);
                }
            }
        }
      
      if (status != DBUS_DISPATCH_COMPLETE)
        return status;
      else if (connection->n_incoming > 0)
        return DBUS_DISPATCH_DATA_REMAINS;
      else
        return DBUS_DISPATCH_COMPLETE;
    }
}

static void
_dbus_connection_update_dispatch_status_and_unlock (DBusConnection    *connection,
                                                    DBusDispatchStatus new_status)
{
  dbus_bool_t changed;
  DBusDispatchStatusFunction function;
  void *data;

  HAVE_LOCK_CHECK (connection);

  _dbus_connection_ref_unlocked (connection);

  changed = new_status != connection->last_dispatch_status;

  connection->last_dispatch_status = new_status;

  function = connection->dispatch_status_function;
  data = connection->dispatch_status_data;

  /* We drop the lock */
  CONNECTION_UNLOCK (connection);
  
  if (changed && function)
    {
      _dbus_verbose ("Notifying of change to dispatch status of %p now %d (%s)\n",
                     connection, new_status,
                     DISPATCH_STATUS_NAME (new_status));
      (* function) (connection, new_status, data);      
    }
  
  dbus_connection_unref (connection);
}

/**
 * Gets the current state (what we would currently return
 * from dbus_connection_dispatch()) but doesn't actually
 * dispatch any messages.
 * 
 * @param connection the connection.
 * @returns current dispatch status
 */
DBusDispatchStatus
dbus_connection_get_dispatch_status (DBusConnection *connection)
{
  DBusDispatchStatus status;

  _dbus_return_val_if_fail (connection != NULL, DBUS_DISPATCH_COMPLETE);

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  CONNECTION_LOCK (connection);

  status = _dbus_connection_get_dispatch_status_unlocked (connection);
  
  CONNECTION_UNLOCK (connection);

  return status;
}

/**
 * Processes data buffered while handling watches, queueing zero or
 * more incoming messages. Then pops the first-received message from
 * the current incoming message queue, runs any handlers for it, and
 * unrefs the message. Returns a status indicating whether messages/data
 * remain, more memory is needed, or all data has been processed.
 * 
 * Even if the dispatch status is #DBUS_DISPATCH_DATA_REMAINS,
 * does not necessarily dispatch a message, as the data may
 * be part of authentication or the like.
 *
 * @todo some FIXME in here about handling DBUS_HANDLER_RESULT_NEED_MEMORY
 *
 * @todo FIXME what if we call out to application code to handle a
 * message, holding the dispatch lock, and the application code runs
 * the main loop and dispatches again? Probably deadlocks at the
 * moment. Maybe we want a dispatch status of DBUS_DISPATCH_IN_PROGRESS,
 * and then the GSource etc. could handle the situation? Right now
 * our GSource is NO_RECURSE
 * 
 * @param connection the connection
 * @returns dispatch status
 */
DBusDispatchStatus
dbus_connection_dispatch (DBusConnection *connection)
{
  DBusMessage *message;
  DBusList *link, *filter_list_copy, *message_link;
  DBusHandlerResult result;
  DBusPendingCall *pending;
  dbus_int32_t reply_serial;
  DBusDispatchStatus status;

  _dbus_return_val_if_fail (connection != NULL, DBUS_DISPATCH_COMPLETE);

  _dbus_verbose ("%s\n", _DBUS_FUNCTION_NAME);
  
  CONNECTION_LOCK (connection);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);
  if (status != DBUS_DISPATCH_DATA_REMAINS)
    {
      /* unlocks and calls out to user code */
      _dbus_connection_update_dispatch_status_and_unlock (connection, status);
      return status;
    }
  
  /* We need to ref the connection since the callback could potentially
   * drop the last ref to it
   */
  _dbus_connection_ref_unlocked (connection);

  _dbus_connection_acquire_dispatch (connection);
  HAVE_LOCK_CHECK (connection);

  message_link = _dbus_connection_pop_message_link_unlocked (connection);
  if (message_link == NULL)
    {
      /* another thread dispatched our stuff */

      _dbus_verbose ("another thread dispatched message (during acquire_dispatch above)\n");
      
      _dbus_connection_release_dispatch (connection);

      status = _dbus_connection_get_dispatch_status_unlocked (connection);

      _dbus_connection_update_dispatch_status_and_unlock (connection, status);
      
      dbus_connection_unref (connection);
      
      return status;
    }

  message = message_link->data;

  _dbus_verbose (" dispatching message %p (%d %s %s '%s')\n",
                 message,
                 dbus_message_get_type (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message));

  result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  
  /* Pending call handling must be first, because if you do
   * dbus_connection_send_with_reply_and_block() or
   * dbus_pending_call_block() then no handlers/filters will be run on
   * the reply. We want consistent semantics in the case where we
   * dbus_connection_dispatch() the reply.
   */
  
  reply_serial = dbus_message_get_reply_serial (message);
  pending = _dbus_hash_table_lookup_int (connection->pending_replies,
                                         reply_serial);
  if (pending)
    {
      _dbus_verbose ("Dispatching a pending reply\n");
      _dbus_pending_call_complete_and_unlock (pending, message);
      pending = NULL; /* it's probably unref'd */
      
      CONNECTION_LOCK (connection);
      _dbus_verbose ("pending call completed in dispatch\n");
      result = DBUS_HANDLER_RESULT_HANDLED;
      goto out;
    }
  
  if (!_dbus_list_copy (&connection->filter_list, &filter_list_copy))
    {
      _dbus_connection_release_dispatch (connection);
      HAVE_LOCK_CHECK (connection);
      
      _dbus_connection_failed_pop (connection, message_link);

      /* unlocks and calls user code */
      _dbus_connection_update_dispatch_status_and_unlock (connection,
                                                          DBUS_DISPATCH_NEED_MEMORY);

      if (pending)
        dbus_pending_call_unref (pending);
      dbus_connection_unref (connection);
      
      return DBUS_DISPATCH_NEED_MEMORY;
    }
  
  _dbus_list_foreach (&filter_list_copy,
		      (DBusForeachFunction)_dbus_message_filter_ref,
		      NULL);

  /* We're still protected from dispatch() reentrancy here
   * since we acquired the dispatcher
   */
  CONNECTION_UNLOCK (connection);
  
  link = _dbus_list_get_first_link (&filter_list_copy);
  while (link != NULL)
    {
      DBusMessageFilter *filter = link->data;
      DBusList *next = _dbus_list_get_next_link (&filter_list_copy, link);

      _dbus_verbose ("  running filter on message %p\n", message);
      result = (* filter->function) (connection, message, filter->user_data);

      if (result != DBUS_HANDLER_RESULT_NOT_YET_HANDLED)
	break;

      link = next;
    }

  _dbus_list_foreach (&filter_list_copy,
		      (DBusForeachFunction)_dbus_message_filter_unref,
		      NULL);
  _dbus_list_clear (&filter_list_copy);
  
  CONNECTION_LOCK (connection);

  if (result == DBUS_HANDLER_RESULT_NEED_MEMORY)
    {
      _dbus_verbose ("No memory in %s\n", _DBUS_FUNCTION_NAME);
      goto out;
    }
  else if (result == DBUS_HANDLER_RESULT_HANDLED)
    {
      _dbus_verbose ("filter handled message in dispatch\n");
      goto out;
    }

  /* We're still protected from dispatch() reentrancy here
   * since we acquired the dispatcher
   */
  _dbus_verbose ("  running object path dispatch on message %p (%d %s %s '%s')\n",
                 message,
                 dbus_message_get_type (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message));

  HAVE_LOCK_CHECK (connection);
  result = _dbus_object_tree_dispatch_and_unlock (connection->objects,
                                                  message);
  
  CONNECTION_LOCK (connection);

  if (result != DBUS_HANDLER_RESULT_NOT_YET_HANDLED)
    {
      _dbus_verbose ("object tree handled message in dispatch\n");
      goto out;
    }

  if (dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_METHOD_CALL)
    {
      DBusMessage *reply;
      DBusString str;
      DBusPreallocatedSend *preallocated;

      _dbus_verbose ("  sending error %s\n",
                     DBUS_ERROR_UNKNOWN_METHOD);
      
      if (!_dbus_string_init (&str))
        {
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error string in dispatch\n");
          goto out;
        }
              
      if (!_dbus_string_append_printf (&str,
                                       "Method \"%s\" with signature \"%s\" on interface \"%s\" doesn't exist\n",
                                       dbus_message_get_member (message),
                                       dbus_message_get_signature (message),
                                       dbus_message_get_interface (message)))
        {
          _dbus_string_free (&str);
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error string in dispatch\n");
          goto out;
        }
      
      reply = dbus_message_new_error (message,
                                      DBUS_ERROR_UNKNOWN_METHOD,
                                      _dbus_string_get_const_data (&str));
      _dbus_string_free (&str);

      if (reply == NULL)
        {
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error reply in dispatch\n");
          goto out;
        }
      
      preallocated = _dbus_connection_preallocate_send_unlocked (connection);

      if (preallocated == NULL)
        {
          dbus_message_unref (reply);
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error send in dispatch\n");
          goto out;
        }

      _dbus_connection_send_preallocated_unlocked_no_update (connection, preallocated,
                                                             reply, NULL);

      dbus_message_unref (reply);
      
      result = DBUS_HANDLER_RESULT_HANDLED;
    }
  
  _dbus_verbose ("  done dispatching %p (%d %s %s '%s') on connection %p\n", message,
                 dbus_message_get_type (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message),
                 connection);
  
 out:
  if (result == DBUS_HANDLER_RESULT_NEED_MEMORY)
    {
      _dbus_verbose ("out of memory in %s\n", _DBUS_FUNCTION_NAME);
      
      /* Put message back, and we'll start over.
       * Yes this means handlers must be idempotent if they
       * don't return HANDLED; c'est la vie.
       */
      _dbus_connection_putback_message_link_unlocked (connection,
                                                      message_link);
    }
  else
    {
      _dbus_verbose (" ... done dispatching in %s\n", _DBUS_FUNCTION_NAME);
      
      if (connection->exit_on_disconnect &&
          dbus_message_is_signal (message,
                                  DBUS_INTERFACE_LOCAL,
                                  "Disconnected"))
        {
          _dbus_verbose ("Exiting on Disconnected signal\n");
          CONNECTION_UNLOCK (connection);
          _dbus_exit (1);
          _dbus_assert_not_reached ("Call to exit() returned");
        }
      
      _dbus_list_free_link (message_link);
      dbus_message_unref (message); /* don't want the message to count in max message limits
                                     * in computing dispatch status below
                                     */
    }
  
  _dbus_connection_release_dispatch (connection);
  HAVE_LOCK_CHECK (connection);

  _dbus_verbose ("%s before final status update\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* unlocks and calls user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
  
  dbus_connection_unref (connection);
  
  return status;
}

/**
 * Sets the watch functions for the connection. These functions are
 * responsible for making the application's main loop aware of file
 * descriptors that need to be monitored for events, using select() or
 * poll(). When using Qt, typically the DBusAddWatchFunction would
 * create a QSocketNotifier. When using GLib, the DBusAddWatchFunction
 * could call g_io_add_watch(), or could be used as part of a more
 * elaborate GSource. Note that when a watch is added, it may
 * not be enabled.
 *
 * The DBusWatchToggledFunction notifies the application that the
 * watch has been enabled or disabled. Call dbus_watch_get_enabled()
 * to check this. A disabled watch should have no effect, and enabled
 * watch should be added to the main loop. This feature is used
 * instead of simply adding/removing the watch because
 * enabling/disabling can be done without memory allocation.  The
 * toggled function may be NULL if a main loop re-queries
 * dbus_watch_get_enabled() every time anyway.
 * 
 * The DBusWatch can be queried for the file descriptor to watch using
 * dbus_watch_get_fd(), and for the events to watch for using
 * dbus_watch_get_flags(). The flags returned by
 * dbus_watch_get_flags() will only contain DBUS_WATCH_READABLE and
 * DBUS_WATCH_WRITABLE, never DBUS_WATCH_HANGUP or DBUS_WATCH_ERROR;
 * all watches implicitly include a watch for hangups, errors, and
 * other exceptional conditions.
 *
 * Once a file descriptor becomes readable or writable, or an exception
 * occurs, dbus_watch_handle() should be called to
 * notify the connection of the file descriptor's condition.
 *
 * dbus_watch_handle() cannot be called during the
 * DBusAddWatchFunction, as the connection will not be ready to handle
 * that watch yet.
 * 
 * It is not allowed to reference a DBusWatch after it has been passed
 * to remove_function.
 *
 * If #FALSE is returned due to lack of memory, the failure may be due
 * to a #FALSE return from the new add_function. If so, the
 * add_function may have been called successfully one or more times,
 * but the remove_function will also have been called to remove any
 * successful adds. i.e. if #FALSE is returned the net result
 * should be that dbus_connection_set_watch_functions() has no effect,
 * but the add_function and remove_function may have been called.
 *
 * @todo We need to drop the lock when we call the
 * add/remove/toggled functions which can be a side effect
 * of setting the watch functions.
 * 
 * @param connection the connection.
 * @param add_function function to begin monitoring a new descriptor.
 * @param remove_function function to stop monitoring a descriptor.
 * @param toggled_function function to notify of enable/disable
 * @param data data to pass to add_function and remove_function.
 * @param free_data_function function to be called to free the data.
 * @returns #FALSE on failure (no memory)
 */
dbus_bool_t
dbus_connection_set_watch_functions (DBusConnection              *connection,
                                     DBusAddWatchFunction         add_function,
                                     DBusRemoveWatchFunction      remove_function,
                                     DBusWatchToggledFunction     toggled_function,
                                     void                        *data,
                                     DBusFreeFunction             free_data_function)
{
  dbus_bool_t retval;
  DBusWatchList *watches;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

#ifndef DBUS_DISABLE_CHECKS
  if (connection->watches == NULL)
    {
      _dbus_warn ("Re-entrant call to %s is not allowed\n",
                  _DBUS_FUNCTION_NAME);
      return FALSE;
    }
#endif
  
  /* ref connection for slightly better reentrancy */
  _dbus_connection_ref_unlocked (connection);

  /* This can call back into user code, and we need to drop the
   * connection lock when it does. This is kind of a lame
   * way to do it.
   */
  watches = connection->watches;
  connection->watches = NULL;
  CONNECTION_UNLOCK (connection);

  retval = _dbus_watch_list_set_functions (watches,
                                           add_function, remove_function,
                                           toggled_function,
                                           data, free_data_function);
  CONNECTION_LOCK (connection);
  connection->watches = watches;
  
  CONNECTION_UNLOCK (connection);
  /* drop our paranoid refcount */
  dbus_connection_unref (connection);
  
  return retval;
}

/**
 * Sets the timeout functions for the connection. These functions are
 * responsible for making the application's main loop aware of timeouts.
 * When using Qt, typically the DBusAddTimeoutFunction would create a
 * QTimer. When using GLib, the DBusAddTimeoutFunction would call
 * g_timeout_add.
 * 
 * The DBusTimeoutToggledFunction notifies the application that the
 * timeout has been enabled or disabled. Call
 * dbus_timeout_get_enabled() to check this. A disabled timeout should
 * have no effect, and enabled timeout should be added to the main
 * loop. This feature is used instead of simply adding/removing the
 * timeout because enabling/disabling can be done without memory
 * allocation. With Qt, QTimer::start() and QTimer::stop() can be used
 * to enable and disable. The toggled function may be NULL if a main
 * loop re-queries dbus_timeout_get_enabled() every time anyway.
 * Whenever a timeout is toggled, its interval may change.
 *
 * The DBusTimeout can be queried for the timer interval using
 * dbus_timeout_get_interval(). dbus_timeout_handle() should be called
 * repeatedly, each time the interval elapses, starting after it has
 * elapsed once. The timeout stops firing when it is removed with the
 * given remove_function.  The timer interval may change whenever the
 * timeout is added, removed, or toggled.
 *
 * @param connection the connection.
 * @param add_function function to add a timeout.
 * @param remove_function function to remove a timeout.
 * @param toggled_function function to notify of enable/disable
 * @param data data to pass to add_function and remove_function.
 * @param free_data_function function to be called to free the data.
 * @returns #FALSE on failure (no memory)
 */
dbus_bool_t
dbus_connection_set_timeout_functions   (DBusConnection            *connection,
					 DBusAddTimeoutFunction     add_function,
					 DBusRemoveTimeoutFunction  remove_function,
                                         DBusTimeoutToggledFunction toggled_function,
					 void                      *data,
					 DBusFreeFunction           free_data_function)
{
  dbus_bool_t retval;
  DBusTimeoutList *timeouts;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

#ifndef DBUS_DISABLE_CHECKS
  if (connection->timeouts == NULL)
    {
      _dbus_warn ("Re-entrant call to %s is not allowed\n",
                  _DBUS_FUNCTION_NAME);
      return FALSE;
    }
#endif
  
  /* ref connection for slightly better reentrancy */
  _dbus_connection_ref_unlocked (connection);

  timeouts = connection->timeouts;
  connection->timeouts = NULL;
  CONNECTION_UNLOCK (connection);
  
  retval = _dbus_timeout_list_set_functions (timeouts,
                                             add_function, remove_function,
                                             toggled_function,
                                             data, free_data_function);
  CONNECTION_LOCK (connection);
  connection->timeouts = timeouts;
  
  CONNECTION_UNLOCK (connection);
  /* drop our paranoid refcount */
  dbus_connection_unref (connection);

  return retval;
}

/**
 * Sets the mainloop wakeup function for the connection. Thi function is
 * responsible for waking up the main loop (if its sleeping) when some some
 * change has happened to the connection that the mainloop needs to reconsiders
 * (e.g. a message has been queued for writing).
 * When using Qt, this typically results in a call to QEventLoop::wakeUp().
 * When using GLib, it would call g_main_context_wakeup().
 *
 *
 * @param connection the connection.
 * @param wakeup_main_function function to wake up the mainloop
 * @param data data to pass wakeup_main_function
 * @param free_data_function function to be called to free the data.
 */
void
dbus_connection_set_wakeup_main_function (DBusConnection            *connection,
					  DBusWakeupMainFunction     wakeup_main_function,
					  void                      *data,
					  DBusFreeFunction           free_data_function)
{
  void *old_data;
  DBusFreeFunction old_free_data;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  old_data = connection->wakeup_main_data;
  old_free_data = connection->free_wakeup_main_data;

  connection->wakeup_main_function = wakeup_main_function;
  connection->wakeup_main_data = data;
  connection->free_wakeup_main_data = free_data_function;
  
  CONNECTION_UNLOCK (connection);

  /* Callback outside the lock */
  if (old_free_data)
    (*old_free_data) (old_data);
}

/**
 * Set a function to be invoked when the dispatch status changes.
 * If the dispatch status is #DBUS_DISPATCH_DATA_REMAINS, then
 * dbus_connection_dispatch() needs to be called to process incoming
 * messages. However, dbus_connection_dispatch() MUST NOT BE CALLED
 * from inside the DBusDispatchStatusFunction. Indeed, almost
 * any reentrancy in this function is a bad idea. Instead,
 * the DBusDispatchStatusFunction should simply save an indication
 * that messages should be dispatched later, when the main loop
 * is re-entered.
 *
 * @param connection the connection
 * @param function function to call on dispatch status changes
 * @param data data for function
 * @param free_data_function free the function data
 */
void
dbus_connection_set_dispatch_status_function (DBusConnection             *connection,
                                              DBusDispatchStatusFunction  function,
                                              void                       *data,
                                              DBusFreeFunction            free_data_function)
{
  void *old_data;
  DBusFreeFunction old_free_data;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  old_data = connection->dispatch_status_data;
  old_free_data = connection->free_dispatch_status_data;

  connection->dispatch_status_function = function;
  connection->dispatch_status_data = data;
  connection->free_dispatch_status_data = free_data_function;
  
  CONNECTION_UNLOCK (connection);

  /* Callback outside the lock */
  if (old_free_data)
    (*old_free_data) (old_data);
}

/**
 * Get the UNIX file descriptor of the connection, if any.  This can
 * be used for SELinux access control checks with getpeercon() for
 * example. DO NOT read or write to the file descriptor, or try to
 * select() on it; use DBusWatch for main loop integration. Not all
 * connections will have a file descriptor. So for adding descriptors
 * to the main loop, use dbus_watch_get_fd() and so forth.
 *
 * @param connection the connection
 * @param fd return location for the file descriptor.
 * @returns #TRUE if fd is successfully obtained.
 */
dbus_bool_t
dbus_connection_get_unix_fd (DBusConnection *connection,
                             int            *fd)
{
  dbus_bool_t retval;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (connection->transport != NULL, FALSE);
  
  CONNECTION_LOCK (connection);
  
  retval = _dbus_transport_get_unix_fd (connection->transport,
                                        fd);

  CONNECTION_UNLOCK (connection);

  return retval;
}

/**
 * Gets the UNIX user ID of the connection if any.
 * Returns #TRUE if the uid is filled in.
 * Always returns #FALSE on non-UNIX platforms.
 * Always returns #FALSE prior to authenticating the
 * connection.
 *
 * @param connection the connection
 * @param uid return location for the user ID
 * @returns #TRUE if uid is filled in with a valid user ID
 */
dbus_bool_t
dbus_connection_get_unix_user (DBusConnection *connection,
                               unsigned long  *uid)
{
  dbus_bool_t result;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (uid != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

  if (!_dbus_transport_get_is_authenticated (connection->transport))
    result = FALSE;
  else
    result = _dbus_transport_get_unix_user (connection->transport,
                                            uid);
  CONNECTION_UNLOCK (connection);

  return result;
}

/**
 * Gets the process ID of the connection if any.
 * Returns #TRUE if the uid is filled in.
 * Always returns #FALSE prior to authenticating the
 * connection.
 *
 * @param connection the connection
 * @param pid return location for the process ID
 * @returns #TRUE if uid is filled in with a valid process ID
 */
dbus_bool_t
dbus_connection_get_unix_process_id (DBusConnection *connection,
				     unsigned long  *pid)
{
  dbus_bool_t result;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (pid != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

  if (!_dbus_transport_get_is_authenticated (connection->transport))
    result = FALSE;
  else
    result = _dbus_transport_get_unix_process_id (connection->transport,
						  pid);
  CONNECTION_UNLOCK (connection);

  return result;
}

/**
 * Sets a predicate function used to determine whether a given user ID
 * is allowed to connect. When an incoming connection has
 * authenticated with a particular user ID, this function is called;
 * if it returns #TRUE, the connection is allowed to proceed,
 * otherwise the connection is disconnected.
 *
 * If the function is set to #NULL (as it is by default), then
 * only the same UID as the server process will be allowed to
 * connect.
 *
 * @param connection the connection
 * @param function the predicate
 * @param data data to pass to the predicate
 * @param free_data_function function to free the data
 */
void
dbus_connection_set_unix_user_function (DBusConnection             *connection,
                                        DBusAllowUnixUserFunction   function,
                                        void                       *data,
                                        DBusFreeFunction            free_data_function)
{
  void *old_data = NULL;
  DBusFreeFunction old_free_function = NULL;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  _dbus_transport_set_unix_user_function (connection->transport,
                                          function, data, free_data_function,
                                          &old_data, &old_free_function);
  CONNECTION_UNLOCK (connection);

  if (old_free_function != NULL)
    (* old_free_function) (old_data);    
}

/**
 * Adds a message filter. Filters are handlers that are run on all
 * incoming messages, prior to the objects registered with
 * dbus_connection_register_object_path().  Filters are run in the
 * order that they were added.  The same handler can be added as a
 * filter more than once, in which case it will be run more than once.
 * Filters added during a filter callback won't be run on the message
 * being processed.
 *
 * @todo we don't run filters on messages while blocking without
 * entering the main loop, since filters are run as part of
 * dbus_connection_dispatch(). This is probably a feature, as filters
 * could create arbitrary reentrancy. But kind of sucks if you're
 * trying to filter METHOD_RETURN for some reason.
 *
 * @param connection the connection
 * @param function function to handle messages
 * @param user_data user data to pass to the function
 * @param free_data_function function to use for freeing user data
 * @returns #TRUE on success, #FALSE if not enough memory.
 */
dbus_bool_t
dbus_connection_add_filter (DBusConnection            *connection,
                            DBusHandleMessageFunction  function,
                            void                      *user_data,
                            DBusFreeFunction           free_data_function)
{
  DBusMessageFilter *filter;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (function != NULL, FALSE);

  filter = dbus_new0 (DBusMessageFilter, 1);
  if (filter == NULL)
    return FALSE;

  filter->refcount.value = 1;
  
  CONNECTION_LOCK (connection);

  if (!_dbus_list_append (&connection->filter_list,
                          filter))
    {
      _dbus_message_filter_unref (filter);
      CONNECTION_UNLOCK (connection);
      return FALSE;
    }

  /* Fill in filter after all memory allocated,
   * so we don't run the free_user_data_function
   * if the add_filter() fails
   */
  
  filter->function = function;
  filter->user_data = user_data;
  filter->free_user_data_function = free_data_function;
        
  CONNECTION_UNLOCK (connection);
  return TRUE;
}

/**
 * Removes a previously-added message filter. It is a programming
 * error to call this function for a handler that has not been added
 * as a filter. If the given handler was added more than once, only
 * one instance of it will be removed (the most recently-added
 * instance).
 *
 * @param connection the connection
 * @param function the handler to remove
 * @param user_data user data for the handler to remove
 *
 */
void
dbus_connection_remove_filter (DBusConnection            *connection,
                               DBusHandleMessageFunction  function,
                               void                      *user_data)
{
  DBusList *link;
  DBusMessageFilter *filter;
  
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (function != NULL);
  
  CONNECTION_LOCK (connection);

  filter = NULL;
  
  link = _dbus_list_get_last_link (&connection->filter_list);
  while (link != NULL)
    {
      filter = link->data;

      if (filter->function == function &&
          filter->user_data == user_data)
        {
          _dbus_list_remove_link (&connection->filter_list, link);
          filter->function = NULL;
          
          break;
        }
        
      link = _dbus_list_get_prev_link (&connection->filter_list, link);
    }
  
  CONNECTION_UNLOCK (connection);

#ifndef DBUS_DISABLE_CHECKS
  if (filter == NULL)
    {
      _dbus_warn ("Attempt to remove filter function %p user data %p, but no such filter has been added\n",
                  function, user_data);
      return;
    }
#endif
  
  /* Call application code */
  if (filter->free_user_data_function)
    (* filter->free_user_data_function) (filter->user_data);

  filter->free_user_data_function = NULL;
  filter->user_data = NULL;
  
  _dbus_message_filter_unref (filter);
}

/**
 * Registers a handler for a given path in the object hierarchy.
 * The given vtable handles messages sent to exactly the given path.
 *
 *
 * @param connection the connection
 * @param path a '/' delimited string of path elements
 * @param vtable the virtual table
 * @param user_data data to pass to functions in the vtable
 * @returns #FALSE if not enough memory
 */
dbus_bool_t
dbus_connection_register_object_path (DBusConnection              *connection,
                                      const char                  *path,
                                      const DBusObjectPathVTable  *vtable,
                                      void                        *user_data)
{
  char **decomposed_path;
  dbus_bool_t retval;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (path != NULL, FALSE);
  _dbus_return_val_if_fail (path[0] == '/', FALSE);
  _dbus_return_val_if_fail (vtable != NULL, FALSE);

  if (!_dbus_decompose_path (path, strlen (path), &decomposed_path, NULL))
    return FALSE;

  CONNECTION_LOCK (connection);

  retval = _dbus_object_tree_register (connection->objects,
                                       FALSE,
                                       (const char **) decomposed_path, vtable,
                                       user_data);

  CONNECTION_UNLOCK (connection);

  dbus_free_string_array (decomposed_path);

  return retval;
}

/**
 * Registers a fallback handler for a given subsection of the object
 * hierarchy.  The given vtable handles messages at or below the given
 * path. You can use this to establish a default message handling
 * policy for a whole "subdirectory."
 *
 * @param connection the connection
 * @param path a '/' delimited string of path elements
 * @param vtable the virtual table
 * @param user_data data to pass to functions in the vtable
 * @returns #FALSE if not enough memory
 */
dbus_bool_t
dbus_connection_register_fallback (DBusConnection              *connection,
                                   const char                  *path,
                                   const DBusObjectPathVTable  *vtable,
                                   void                        *user_data)
{
  char **decomposed_path;
  dbus_bool_t retval;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (path != NULL, FALSE);
  _dbus_return_val_if_fail (path[0] == '/', FALSE);
  _dbus_return_val_if_fail (vtable != NULL, FALSE);

  if (!_dbus_decompose_path (path, strlen (path), &decomposed_path, NULL))
    return FALSE;

  CONNECTION_LOCK (connection);

  retval = _dbus_object_tree_register (connection->objects,
                                       TRUE,
				       (const char **) decomposed_path, vtable,
                                       user_data);

  CONNECTION_UNLOCK (connection);

  dbus_free_string_array (decomposed_path);

  return retval;
}

/**
 * Unregisters the handler registered with exactly the given path.
 * It's a bug to call this function for a path that isn't registered.
 * Can unregister both fallback paths and object paths.
 *
 * @param connection the connection
 * @param path a '/' delimited string of path elements
 * @returns #FALSE if not enough memory
 */
dbus_bool_t
dbus_connection_unregister_object_path (DBusConnection              *connection,
                                        const char                  *path)
{
  char **decomposed_path;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (path != NULL, FALSE);
  _dbus_return_val_if_fail (path[0] == '/', FALSE);

  if (!_dbus_decompose_path (path, strlen (path), &decomposed_path, NULL))
      return FALSE;

  CONNECTION_LOCK (connection);

  _dbus_object_tree_unregister_and_unlock (connection->objects, (const char **) decomposed_path);

  dbus_free_string_array (decomposed_path);

  return TRUE;
}

/**
 * Lists the registered fallback handlers and object path handlers at
 * the given parent_path. The returned array should be freed with
 * dbus_free_string_array().
 *
 * @param connection the connection
 * @param parent_path the path to list the child handlers of
 * @param child_entries returns #NULL-terminated array of children
 * @returns #FALSE if no memory to allocate the child entries
 */
dbus_bool_t
dbus_connection_list_registered (DBusConnection              *connection,
                                 const char                  *parent_path,
                                 char                      ***child_entries)
{
  char **decomposed_path;
  dbus_bool_t retval;
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (parent_path != NULL, FALSE);
  _dbus_return_val_if_fail (parent_path[0] == '/', FALSE);
  _dbus_return_val_if_fail (child_entries != NULL, FALSE);

  if (!_dbus_decompose_path (parent_path, strlen (parent_path), &decomposed_path, NULL))
    return FALSE;

  CONNECTION_LOCK (connection);

  retval = _dbus_object_tree_list_registered_and_unlock (connection->objects,
							 (const char **) decomposed_path,
							 child_entries);
  dbus_free_string_array (decomposed_path);

  return retval;
}

static DBusDataSlotAllocator slot_allocator;
_DBUS_DEFINE_GLOBAL_LOCK (connection_slots);

/**
 * Allocates an integer ID to be used for storing application-specific
 * data on any DBusConnection. The allocated ID may then be used
 * with dbus_connection_set_data() and dbus_connection_get_data().
 * The passed-in slot must be initialized to -1, and is filled in
 * with the slot ID. If the passed-in slot is not -1, it's assumed
 * to be already allocated, and its refcount is incremented.
 * 
 * The allocated slot is global, i.e. all DBusConnection objects will
 * have a slot with the given integer ID reserved.
 *
 * @param slot_p address of a global variable storing the slot
 * @returns #FALSE on failure (no memory)
 */
dbus_bool_t
dbus_connection_allocate_data_slot (dbus_int32_t *slot_p)
{
  return _dbus_data_slot_allocator_alloc (&slot_allocator,
                                          _DBUS_LOCK_NAME (connection_slots),
                                          slot_p);
}

/**
 * Deallocates a global ID for connection data slots.
 * dbus_connection_get_data() and dbus_connection_set_data() may no
 * longer be used with this slot.  Existing data stored on existing
 * DBusConnection objects will be freed when the connection is
 * finalized, but may not be retrieved (and may only be replaced if
 * someone else reallocates the slot).  When the refcount on the
 * passed-in slot reaches 0, it is set to -1.
 *
 * @param slot_p address storing the slot to deallocate
 */
void
dbus_connection_free_data_slot (dbus_int32_t *slot_p)
{
  _dbus_return_if_fail (*slot_p >= 0);
  
  _dbus_data_slot_allocator_free (&slot_allocator, slot_p);
}

/**
 * Stores a pointer on a DBusConnection, along
 * with an optional function to be used for freeing
 * the data when the data is set again, or when
 * the connection is finalized. The slot number
 * must have been allocated with dbus_connection_allocate_data_slot().
 *
 * @param connection the connection
 * @param slot the slot number
 * @param data the data to store
 * @param free_data_func finalizer function for the data
 * @returns #TRUE if there was enough memory to store the data
 */
dbus_bool_t
dbus_connection_set_data (DBusConnection   *connection,
                          dbus_int32_t      slot,
                          void             *data,
                          DBusFreeFunction  free_data_func)
{
  DBusFreeFunction old_free_func;
  void *old_data;
  dbus_bool_t retval;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (slot >= 0, FALSE);
  
  CONNECTION_LOCK (connection);

  retval = _dbus_data_slot_list_set (&slot_allocator,
                                     &connection->slot_list,
                                     slot, data, free_data_func,
                                     &old_free_func, &old_data);
  
  CONNECTION_UNLOCK (connection);

  if (retval)
    {
      /* Do the actual free outside the connection lock */
      if (old_free_func)
        (* old_free_func) (old_data);
    }

  return retval;
}

/**
 * Retrieves data previously set with dbus_connection_set_data().
 * The slot must still be allocated (must not have been freed).
 *
 * @param connection the connection
 * @param slot the slot to get data from
 * @returns the data, or #NULL if not found
 */
void*
dbus_connection_get_data (DBusConnection   *connection,
                          dbus_int32_t      slot)
{
  void *res;

  _dbus_return_val_if_fail (connection != NULL, NULL);
  
  CONNECTION_LOCK (connection);

  res = _dbus_data_slot_list_get (&slot_allocator,
                                  &connection->slot_list,
                                  slot);
  
  CONNECTION_UNLOCK (connection);

  return res;
}

/**
 * This function sets a global flag for whether dbus_connection_new()
 * will set SIGPIPE behavior to SIG_IGN.
 *
 * @param will_modify_sigpipe #TRUE to allow sigpipe to be set to SIG_IGN
 */
void
dbus_connection_set_change_sigpipe (dbus_bool_t will_modify_sigpipe)
{  
  _dbus_modify_sigpipe = will_modify_sigpipe != FALSE;
}

/**
 * Specifies the maximum size message this connection is allowed to
 * receive. Larger messages will result in disconnecting the
 * connection.
 * 
 * @param connection a #DBusConnection
 * @param size maximum message size the connection can receive, in bytes
 */
void
dbus_connection_set_max_message_size (DBusConnection *connection,
                                      long            size)
{
  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  _dbus_transport_set_max_message_size (connection->transport,
                                        size);
  CONNECTION_UNLOCK (connection);
}

/**
 * Gets the value set by dbus_connection_set_max_message_size().
 *
 * @param connection the connection
 * @returns the max size of a single message
 */
long
dbus_connection_get_max_message_size (DBusConnection *connection)
{
  long res;

  _dbus_return_val_if_fail (connection != NULL, 0);
  
  CONNECTION_LOCK (connection);
  res = _dbus_transport_get_max_message_size (connection->transport);
  CONNECTION_UNLOCK (connection);
  return res;
}

/**
 * Sets the maximum total number of bytes that can be used for all messages
 * received on this connection. Messages count toward the maximum until
 * they are finalized. When the maximum is reached, the connection will
 * not read more data until some messages are finalized.
 *
 * The semantics of the maximum are: if outstanding messages are
 * already above the maximum, additional messages will not be read.
 * The semantics are not: if the next message would cause us to exceed
 * the maximum, we don't read it. The reason is that we don't know the
 * size of a message until after we read it.
 *
 * Thus, the max live messages size can actually be exceeded
 * by up to the maximum size of a single message.
 * 
 * Also, if we read say 1024 bytes off the wire in a single read(),
 * and that contains a half-dozen small messages, we may exceed the
 * size max by that amount. But this should be inconsequential.
 *
 * This does imply that we can't call read() with a buffer larger
 * than we're willing to exceed this limit by.
 *
 * @param connection the connection
 * @param size the maximum size in bytes of all outstanding messages
 */
void
dbus_connection_set_max_received_size (DBusConnection *connection,
                                       long            size)
{
  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  _dbus_transport_set_max_received_size (connection->transport,
                                         size);
  CONNECTION_UNLOCK (connection);
}

/**
 * Gets the value set by dbus_connection_set_max_received_size().
 *
 * @param connection the connection
 * @returns the max size of all live messages
 */
long
dbus_connection_get_max_received_size (DBusConnection *connection)
{
  long res;

  _dbus_return_val_if_fail (connection != NULL, 0);
  
  CONNECTION_LOCK (connection);
  res = _dbus_transport_get_max_received_size (connection->transport);
  CONNECTION_UNLOCK (connection);
  return res;
}

/**
 * Gets the approximate size in bytes of all messages in the outgoing
 * message queue. The size is approximate in that you shouldn't use
 * it to decide how many bytes to read off the network or anything
 * of that nature, as optimizations may choose to tell small white lies
 * to avoid performance overhead.
 *
 * @param connection the connection
 * @returns the number of bytes that have been queued up but not sent
 */
long
dbus_connection_get_outgoing_size (DBusConnection *connection)
{
  long res;

  _dbus_return_val_if_fail (connection != NULL, 0);
  
  CONNECTION_LOCK (connection);
  res = _dbus_counter_get_value (connection->outgoing_counter);
  CONNECTION_UNLOCK (connection);
  return res;
}

/** @} */