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
|
/**
* mds — A micro-display server
* Copyright © 2014, 2015 Mattias Andrée (maandree@member.fsf.org)
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include "comm.h"
#include <stdlib.h>
#include <unistd.h>
/**
* Initialise a connection descriptor
*
* @param this The connection descriptor
* @return Zero on success, -1 on error, `ernno`
* will have been set accordingly on error
*
* @throws EAGAIN See pthread_mutex_init(3)
* @throws ENOMEM See pthread_mutex_init(3)
* @throws EPERM See pthread_mutex_init(3)
*/
int libmds_connection_initialise(libmds_connection_t* restrict this)
{
this->socket_fd = -1;
this->message_id = UINT32_MAX;
this->client_id = NULL;
this->mutex_initialised = 0;
errno = pthread_mutex_init(&(this->mutex), NULL);
if (errno)
return -1;
this->mutex_initialised = 1;
return 0;
}
/**
* Allocate and initialise a connection descriptor
*
* @return The connection descriptor, `NULL` on error,
* `errno` will have been set accordingly on error
*
* @throws ENOMEM Out of memory, Possibly, the process hit the RLIMIT_AS or
* RLIMIT_DATA limit described in getrlimit(2).
* @throws EAGAIN See pthread_mutex_init(3)
* @throws EPERM See pthread_mutex_init(3)
*/
libmds_connection_t* libmds_connection_create(void)
{
libmds_connection_t* rc = malloc(sizeof(libmds_connection_t));
if (rc == NULL)
return NULL;
return libmds_connection_initialise(rc) ? NULL : rc;
}
/**
* Release all resources held by a connection descriptor
*
* @param this The connection descriptor, may be `NULL`
*/
void libmds_connection_destroy(libmds_connection_t* restrict this)
{
if (this == NULL)
return;
if (this->socket_fd >= 0)
{
while (close(this->socket_fd))
{
if (errno == EINTR)
continue;
break; /* errno may be EBADF or EIO. */
}
this->socket_fd = -1;
}
free(this->client_id);
this->client_id = NULL;
if (this->mutex_initialised)
{
this->mutex_initialised = 0;
pthread_mutex_destroy(&(this->mutex)); /* Can return EBUSY. */
}
}
/**
* Release all resources held by a connection descriptor,
* and release the allocation of the connection descriptor
*
* @param this The connection descriptor, may be `NULL`
*/
void libmds_connection_free(libmds_connection_t* restrict this)
{
libmds_connection_destroy(this);
free(this);
}
/**
* Wrapper for `libmds_connection_send_unlocked` that locks
* the mutex of the connection
*
* @param this The connection descriptor, must not be `NULL`
* @param message The message to send, must not be `NULL`
* @param length The length of the message, should be positive
* @return Zero on success, -1 on error, `ernno`
* will have been set accordingly on error
*
* @throws See pthread_mutex_lock(3)
*/
int libmds_connection_send(libmds_connection_t* restrict this, const char* message, size_t length)
{
int r, saved_errno;
if (libmds_connection_lock(this))
return -1;
r = libmds_connection_send_unlocked(this, message, length);
saved_errno = errno;
(void) libmds_connection_unlock(this);
return errno = saved_errno, r;
}
int libmds_connection_send_unlocked(libmds_connection_t* restrict this, const char* message, size_t length)
{
return (void) this, (void) message, (void) length, 0; /* TODO */
}
|
