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
|
/**
* mds — A micro-display server
* Copyright © 2014 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/>.
*/
#ifndef MDS_MDS_SERVER_H
#define MDS_MDS_SERVER_H
#include <libmdsserver/mds-message.h>
#include <stdlib.h>
#include <pthread.h>
#include <stdint.h>
/**
* A condition for a message being intercepted by a client
*/
typedef struct interception_condition
{
/**
* The header of messages to intercept, optionally with a value,
* empty (most not be NULL) for all messages.
*/
char* condition;
/**
* The hash of the header of messages to intercept
*/
size_t header_hash;
/**
* The interception priority. The client should be
* consistent with the priority for conditions that
* are not mutually exclusive.
*/
int64_t priority;
/**
* Whether the messages may get modified by the client
*/
int modifying;
} interception_condition_t;
/**
* Client information structure
*/
typedef struct client
{
/**
* The client's entry in the list of clients
*/
ssize_t list_entry;
/**
* The socket file descriptor for the socket connected to the client
*/
int socket_fd;
/**
* Whether the socket is open
*/
int open;
/**
* Message read buffer for the client
*/
mds_message_t message;
/**
* The read thread for the client
*/
pthread_t thread;
/**
* The client's ID
*/
uint64_t id;
/**
* Mutex for sending data and other
* actions that only affacts this client
*/
pthread_mutex_t mutex;
/**
* The messages interception conditions conditions
* for the client
*/
interception_condition_t* interception_conditions;
/**
* The number of interception conditions
*/
size_t interception_conditions_count;
/**
* Messages pending to be sent (concatenated)
*/
char* send_pending;
/**
* The character length of the messages pending to be sent
*/
size_t send_pending_size;
} client_t;
/**
* A queued interception
*/
typedef struct queued_interception
{
/**
* The intercepting client
*/
client_t* client;
/**
* The interception priority
*/
int64_t priority;
/**
* Whether the messages may get modified by the client
*/
int modifying;
} queued_interception_t;
/**
* Master function for slave threads
*
* @param data Input data
* @return Outout data
*/
void* slave_loop(void* data);
/**
* Perform actions that should be taken when
* a message has been received from a client
*
* @param client The client has sent a message
*/
void message_received(client_t* client);
/**
* Add an interception condition for a client
*
* @param client The client
* @param condition The header, optionally with value, to look for, or empty (not `NULL`) for all messages
* @param priority Interception priority
* @param modifying Whether the client may modify the messages
* @param stop Whether the condition should be removed rather than added
*/
void add_intercept_condition(client_t* client, char* condition, int64_t priority, int modifying, int stop);
/**
* Multicast a message
*
* @param message The message
* @param length The length of the message
*/
void multicast_message(char* message, size_t length);
/**
* Exec into the mdsinitrc script
*
* @param args The arguments to the child process
*/
void run_initrc(char** args);
/**
* Called with the signal SIGUSR1 is caught.
* This function should cue a re-exec of the program.
*
* @param signo The caught signal
*/
void sigusr1_trap(int signo);
/**
* Marshal the server's state into a file
*
* @param fd The file descriptor
* @return Negative on error
*/
int marshal_server(int fd);
/**
* Unmarshal the server's state from a file
*
* @param fd The file descriptor
* @return Negative on error
*/
int unmarshal_server(int fd);
#endif
|
