tio.c - plan9port - [fork] Plan 9 from user space | |
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tio.c (2279B) | |
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1 /* Copyright (C) 2003 Russ Cox, Massachusetts Institute of Technology */ | |
2 /* See COPYRIGHT */ | |
3 | |
4 #include <u.h> | |
5 #include <libc.h> | |
6 #include <mux.h> | |
7 | |
8 /* | |
9 * If you fork off two procs running muxrecvproc and muxsendproc, | |
10 * then muxrecv/muxsend (and thus muxrpc) will never block except on | |
11 * rendevouses, which is nice when it's running in one thread of many. | |
12 */ | |
13 void | |
14 _muxrecvproc(void *v) | |
15 { | |
16 void *p; | |
17 Mux *mux; | |
18 Muxqueue *q; | |
19 | |
20 mux = v; | |
21 q = _muxqalloc(); | |
22 | |
23 qlock(&mux->lk); | |
24 mux->readq = q; | |
25 qlock(&mux->inlk); | |
26 rwakeup(&mux->rpcfork); | |
27 qunlock(&mux->lk); | |
28 | |
29 while((p = mux->recv(mux)) != nil) | |
30 if(_muxqsend(q, p) < 0){ | |
31 free(p); | |
32 break; | |
33 } | |
34 qunlock(&mux->inlk); | |
35 qlock(&mux->lk); | |
36 _muxqhangup(q); | |
37 p = nil; | |
38 while(_muxnbqrecv(q, &p) && p != nil){ | |
39 free(p); | |
40 p = nil; | |
41 } | |
42 free(q); | |
43 mux->readq = nil; | |
44 rwakeup(&mux->rpcfork); | |
45 qunlock(&mux->lk); | |
46 } | |
47 | |
48 void | |
49 _muxsendproc(void *v) | |
50 { | |
51 Muxqueue *q; | |
52 void *p; | |
53 Mux *mux; | |
54 | |
55 mux = v; | |
56 q = _muxqalloc(); | |
57 | |
58 qlock(&mux->lk); | |
59 mux->writeq = q; | |
60 qlock(&mux->outlk); | |
61 rwakeup(&mux->rpcfork); | |
62 qunlock(&mux->lk); | |
63 | |
64 while((p = _muxqrecv(q)) != nil) | |
65 if(mux->send(mux, p) < 0) | |
66 break; | |
67 qunlock(&mux->outlk); | |
68 qlock(&mux->lk); | |
69 _muxqhangup(q); | |
70 while(_muxnbqrecv(q, &p)) | |
71 free(p); | |
72 free(q); | |
73 mux->writeq = nil; | |
74 rwakeup(&mux->rpcfork); | |
75 qunlock(&mux->lk); | |
76 return; | |
77 } | |
78 | |
79 int | |
80 _muxrecv(Mux *mux, int canblock, void **vp) | |
81 { | |
82 void *p; | |
83 int ret; | |
84 | |
85 qlock(&mux->lk); | |
86 if(mux->readq){ | |
87 qunlock(&mux->lk); | |
88 if(canblock){ | |
89 *vp = _muxqrecv(mux->readq); | |
90 return 1; | |
91 } | |
92 return _muxnbqrecv(mux->readq, vp); | |
93 } | |
94 | |
95 qlock(&mux->inlk); | |
96 qunlock(&mux->lk); | |
97 if(canblock){ | |
98 p = mux->recv(mux); | |
99 ret = 1; | |
100 }else{ | |
101 if(mux->nbrecv) | |
102 ret = mux->nbrecv(mux, &p); | |
103 else{ | |
104 /* send eof, not "no packet ready" */ | |
105 p = nil; | |
106 ret = 1; | |
107 } | |
108 } | |
109 qunlock(&mux->inlk); | |
110 *vp = p; | |
111 return ret; | |
112 } | |
113 | |
114 int | |
115 _muxsend(Mux *mux, void *p) | |
116 { | |
117 qlock(&mux->lk); | |
118 /* | |
119 if(mux->state != VtStateConnected){ | |
120 packetfree(p); | |
121 werrstr("not connected"); | |
122 qunlock(&mux->lk); | |
123 return -1; | |
124 } | |
125 */ | |
126 if(mux->writeq){ | |
127 qunlock(&mux->lk); | |
128 if(_muxqsend(mux->writeq, p) < 0){ | |
129 free(p); | |
130 return -1; | |
131 } | |
132 return 0; | |
133 } | |
134 | |
135 qlock(&mux->outlk); | |
136 qunlock(&mux->lk); | |
137 if(mux->send(mux, p) < 0){ | |
138 qunlock(&mux->outlk); | |
139 /* vthangup(mux); */ | |
140 return -1; | |
141 } | |
142 qunlock(&mux->outlk); | |
143 return 0; | |
144 } |