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
|
/*
Copyright (c) 2011-2012 250bpm s.r.o.
Copyright (c) 2011 VMware, Inc.
Copyright (c) 2011 Other contributors as noted in the AUTHORS file
This file is part of Crossroads I/O project.
Crossroads I/O is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
Crossroads 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 Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "dist.hpp"
#include "pipe.hpp"
#include "err.hpp"
#include "msg.hpp"
#include "likely.hpp"
xs::dist_t::dist_t () :
matching (0),
active (0),
eligible (0),
more (false)
{
}
xs::dist_t::~dist_t ()
{
xs_assert (pipes.empty ());
}
void xs::dist_t::attach (pipe_t *pipe_)
{
// If we are in the middle of sending a message, we'll add new pipe
// into the list of eligible pipes. Otherwise we add it to the list
// of active pipes.
if (more) {
pipes.push_back (pipe_);
pipes.swap (eligible, pipes.size () - 1);
eligible++;
}
else {
pipes.push_back (pipe_);
pipes.swap (active, pipes.size () - 1);
active++;
eligible++;
}
}
void xs::dist_t::match (pipe_t *pipe_)
{
// If pipe is already matching do nothing.
if (pipes.index (pipe_) < matching)
return;
// If the pipe isn't eligible, ignore it.
if (pipes.index (pipe_) >= eligible)
return;
// Mark the pipe as matching.
pipes.swap (pipes.index (pipe_), matching);
matching++;
}
void xs::dist_t::unmatch ()
{
matching = 0;
}
void xs::dist_t::terminated (pipe_t *pipe_)
{
// Remove the pipe from the list; adjust number of matching, active and/or
// eligible pipes accordingly.
int i = pipes.index (pipe_);
if (i < (int) matching) {
pipes [i] = pipes [matching - 1];
pipes [matching - 1] = NULL;
if (pipes [i])
((pipes_t::item_t*) pipes [i])->set_array_index (i);
--matching;
i = matching;
}
if (i < (int) active) {
pipes [i] = pipes [active - 1];
pipes [active - 1] = NULL;
if (pipes [i])
((pipes_t::item_t*) pipes [i])->set_array_index (i);
--active;
i = active;
}
if (i < (int) eligible) {
pipes [i] = pipes [eligible - 1];
pipes [eligible - 1] = NULL;
if (pipes [i])
((pipes_t::item_t*) pipes [i])->set_array_index (i);
--eligible;
i = eligible;
}
pipes.erase (i);
}
void xs::dist_t::activated (pipe_t *pipe_)
{
// Move the pipe from passive to eligible state.
pipes.swap (pipes.index (pipe_), eligible);
eligible++;
// If there's no message being sent at the moment, move it to
// the active state.
if (!more) {
pipes.swap (eligible - 1, active);
active++;
}
}
int xs::dist_t::send_to_all (msg_t *msg_, int flags_)
{
matching = active;
return send_to_matching (msg_, flags_);
}
int xs::dist_t::send_to_matching (msg_t *msg_, int flags_)
{
// Is this end of a multipart message?
bool msg_more = msg_->flags () & msg_t::more ? true : false;
// Push the message to matching pipes.
distribute (msg_, flags_);
// If mutlipart message is fully sent, activate all the eligible pipes.
if (!msg_more)
active = eligible;
more = msg_more;
return 0;
}
void xs::dist_t::distribute (msg_t *msg_, int flags_)
{
// If there are no matching pipes available, simply drop the message.
if (matching == 0) {
int rc = msg_->close ();
errno_assert (rc == 0);
rc = msg_->init ();
errno_assert (rc == 0);
return;
}
if (msg_->is_vsm ()) {
for (pipes_t::size_type i = 0; i < matching; ++i)
if (!write (pipes [i], msg_))
--i;
int rc = msg_->close();
errno_assert (rc == 0);
rc = msg_->init ();
errno_assert (rc == 0);
return;
}
// Add matching-1 references to the message. We already hold one reference,
// that's why -1.
msg_->add_refs ((int) matching - 1);
// Push copy of the message to each matching pipe.
int failed = 0;
for (pipes_t::size_type i = 0; i < matching; ++i)
if (!write (pipes [i], msg_)) {
--i;
++failed;
}
if (unlikely (failed))
msg_->rm_refs (failed);
// Detach the original message from the data buffer. Note that we don't
// close the message. That's because we've already used all the references.
int rc = msg_->init ();
errno_assert (rc == 0);
}
bool xs::dist_t::has_out ()
{
return true;
}
bool xs::dist_t::write (pipe_t *pipe_, msg_t *msg_)
{
if (!pipe_->write (msg_)) {
pipes.swap (pipes.index (pipe_), matching - 1);
matching--;
pipes.swap (pipes.index (pipe_), active - 1);
active--;
pipes.swap (active, eligible - 1);
eligible--;
return false;
}
if (!(msg_->flags () & msg_t::more))
pipe_->flush ();
return true;
}
|
