1 /*
2 Copyright (c) 2012-2013 Martin Sustrik All rights reserved.
3
4 Permission is hereby granted, free of charge, to any person obtaining a copy
5 of this software and associated documentation files (the "Software"),
6 to deal in the Software without restriction, including without limitation
7 the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 and/or sell copies of the Software, and to permit persons to whom
9 the Software is furnished to do so, subject to the following conditions:
10
11 The above copyright notice and this permission notice shall be included
12 in all copies or substantial portions of the Software.
13
14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
20 IN THE SOFTWARE.
21 */
22
23 #include "excl.h"
24
25 #include "../../utils/fast.h"
26 #include "../../utils/err.h"
27 #include "../../utils/attr.h"
28
nn_excl_init(struct nn_excl * self)29 void nn_excl_init (struct nn_excl *self)
30 {
31 self->pipe = NULL;
32 self->inpipe = NULL;
33 self->outpipe = NULL;
34 }
35
nn_excl_term(struct nn_excl * self)36 void nn_excl_term (struct nn_excl *self)
37 {
38 nn_assert (!self->pipe);
39 nn_assert (!self->inpipe);
40 nn_assert (!self->outpipe);
41 }
42
nn_excl_add(struct nn_excl * self,struct nn_pipe * pipe)43 int nn_excl_add (struct nn_excl *self, struct nn_pipe *pipe)
44 {
45 /* If there's a connection being used, reject any new connection. */
46 if (self->pipe)
47 return -EISCONN;
48
49 /* Remember that this pipe is the active one. */
50 self->pipe = pipe;
51
52 return 0;
53 }
54
nn_excl_rm(struct nn_excl * self,NN_UNUSED struct nn_pipe * pipe)55 void nn_excl_rm (struct nn_excl *self, NN_UNUSED struct nn_pipe *pipe)
56 {
57 nn_assert (self->pipe);
58 self->pipe = NULL;
59 self->inpipe = NULL;
60 self->outpipe = NULL;
61 }
62
nn_excl_in(struct nn_excl * self,struct nn_pipe * pipe)63 void nn_excl_in (struct nn_excl *self, struct nn_pipe *pipe)
64 {
65 nn_assert (!self->inpipe);
66 nn_assert (pipe == self->pipe);
67 self->inpipe = pipe;
68 }
69
nn_excl_out(struct nn_excl * self,struct nn_pipe * pipe)70 void nn_excl_out (struct nn_excl *self, struct nn_pipe *pipe)
71 {
72 nn_assert (!self->outpipe);
73 nn_assert (pipe == self->pipe);
74 self->outpipe = pipe;
75 }
76
nn_excl_send(struct nn_excl * self,struct nn_msg * msg)77 int nn_excl_send (struct nn_excl *self, struct nn_msg *msg)
78 {
79 int rc;
80
81 if (nn_slow (!self->outpipe))
82 return -EAGAIN;
83
84 rc = nn_pipe_send (self->outpipe, msg);
85 errnum_assert (rc >= 0, -rc);
86
87 if (rc & NN_PIPE_RELEASE)
88 self->outpipe = NULL;
89
90 return rc & ~NN_PIPE_RELEASE;
91 }
92
nn_excl_recv(struct nn_excl * self,struct nn_msg * msg)93 int nn_excl_recv (struct nn_excl *self, struct nn_msg *msg)
94 {
95 int rc;
96
97 if (nn_slow (!self->inpipe))
98 return -EAGAIN;
99
100 rc = nn_pipe_recv (self->inpipe, msg);
101 errnum_assert (rc >= 0, -rc);
102
103 if (rc & NN_PIPE_RELEASE)
104 self->inpipe = NULL;
105
106 return rc & ~NN_PIPE_RELEASE;
107 }
108
nn_excl_can_send(struct nn_excl * self)109 int nn_excl_can_send (struct nn_excl *self)
110 {
111 return self->outpipe ? 1 : 0;
112 }
113
nn_excl_can_recv(struct nn_excl * self)114 int nn_excl_can_recv (struct nn_excl *self)
115 {
116 return self->inpipe ? 1 : 0;
117 }
118
119