1 /*
2 * Copyright 6WIND S.A., 2014
3 *
4 * This work is licensed under the terms of the GNU GPL, version 2 or
5 * (at your option) any later version. See the COPYING file in the
6 * top-level directory.
7 */
8
9 #include "qemu/osdep.h"
10 #include "qapi/error.h"
11 #include "qemu/cutils.h"
12 #include "qemu/option.h"
13 #include "ivshmem-server.h"
14
15 #define IVSHMEM_SERVER_DEFAULT_VERBOSE 0
16 #define IVSHMEM_SERVER_DEFAULT_FOREGROUND 0
17 #define IVSHMEM_SERVER_DEFAULT_PID_FILE "/var/run/ivshmem-server.pid"
18 #define IVSHMEM_SERVER_DEFAULT_UNIX_SOCK_PATH "/tmp/ivshmem_socket"
19 #define IVSHMEM_SERVER_DEFAULT_SHM_PATH "ivshmem"
20 #define IVSHMEM_SERVER_DEFAULT_SHM_SIZE (4 * 1024 * 1024)
21 #define IVSHMEM_SERVER_DEFAULT_N_VECTORS 1
22
23 /* used to quit on signal SIGTERM */
24 static int ivshmem_server_quit;
25
26 /* arguments given by the user */
27 typedef struct IvshmemServerArgs {
28 bool verbose;
29 bool foreground;
30 const char *pid_file;
31 const char *unix_socket_path;
32 const char *shm_path;
33 bool use_shm_open;
34 uint64_t shm_size;
35 unsigned n_vectors;
36 } IvshmemServerArgs;
37
38 static void
ivshmem_server_usage(const char * progname)39 ivshmem_server_usage(const char *progname)
40 {
41 printf("Usage: %s [OPTION]...\n"
42 " -h: show this help\n"
43 " -v: verbose mode\n"
44 " -F: foreground mode (default is to daemonize)\n"
45 " -p <pid-file>: path to the PID file (used in daemon mode only)\n"
46 " default " IVSHMEM_SERVER_DEFAULT_PID_FILE "\n"
47 " -S <unix-socket-path>: path to the unix socket to listen to\n"
48 " default " IVSHMEM_SERVER_DEFAULT_UNIX_SOCK_PATH "\n"
49 " -M <shm-name>: POSIX shared memory object to use\n"
50 " default " IVSHMEM_SERVER_DEFAULT_SHM_PATH "\n"
51 " -m <dir-name>: where to create shared memory\n"
52 " -l <size>: size of shared memory in bytes\n"
53 " suffixes K, M and G can be used, e.g. 1K means 1024\n"
54 " default %u\n"
55 " -n <nvectors>: number of vectors\n"
56 " default %u\n",
57 progname, IVSHMEM_SERVER_DEFAULT_SHM_SIZE,
58 IVSHMEM_SERVER_DEFAULT_N_VECTORS);
59 }
60
61 static void
ivshmem_server_help(const char * progname)62 ivshmem_server_help(const char *progname)
63 {
64 fprintf(stderr, "Try '%s -h' for more information.\n", progname);
65 }
66
67 /* parse the program arguments, exit on error */
68 static void
ivshmem_server_parse_args(IvshmemServerArgs * args,int argc,char * argv[])69 ivshmem_server_parse_args(IvshmemServerArgs *args, int argc, char *argv[])
70 {
71 int c;
72 uint64_t v;
73 Error *err = NULL;
74
75 while ((c = getopt(argc, argv, "hvFp:S:m:M:l:n:")) != -1) {
76
77 switch (c) {
78 case 'h': /* help */
79 ivshmem_server_usage(argv[0]);
80 exit(0);
81 break;
82
83 case 'v': /* verbose */
84 args->verbose = 1;
85 break;
86
87 case 'F': /* foreground */
88 args->foreground = 1;
89 break;
90
91 case 'p': /* pid file */
92 args->pid_file = optarg;
93 break;
94
95 case 'S': /* unix socket path */
96 args->unix_socket_path = optarg;
97 break;
98
99 case 'M': /* shm name */
100 case 'm': /* dir name */
101 args->shm_path = optarg;
102 args->use_shm_open = c == 'M';
103 break;
104
105 case 'l': /* shm size */
106 if (!parse_option_size("shm_size", optarg, &args->shm_size,
107 &err)) {
108 error_report_err(err);
109 ivshmem_server_help(argv[0]);
110 exit(1);
111 }
112 break;
113
114 case 'n': /* number of vectors */
115 if (parse_uint_full(optarg, 0, &v) < 0) {
116 fprintf(stderr, "cannot parse n_vectors\n");
117 ivshmem_server_help(argv[0]);
118 exit(1);
119 }
120 args->n_vectors = v;
121 break;
122
123 default:
124 ivshmem_server_usage(argv[0]);
125 exit(1);
126 break;
127 }
128 }
129
130 if (args->n_vectors > IVSHMEM_SERVER_MAX_VECTORS) {
131 fprintf(stderr, "too many requested vectors (max is %d)\n",
132 IVSHMEM_SERVER_MAX_VECTORS);
133 ivshmem_server_help(argv[0]);
134 exit(1);
135 }
136
137 if (args->verbose == 1 && args->foreground == 0) {
138 fprintf(stderr, "cannot use verbose in daemon mode\n");
139 ivshmem_server_help(argv[0]);
140 exit(1);
141 }
142 }
143
144 /* wait for events on listening server unix socket and connected client
145 * sockets */
146 static int
ivshmem_server_poll_events(IvshmemServer * server)147 ivshmem_server_poll_events(IvshmemServer *server)
148 {
149 fd_set fds;
150 int ret = 0, maxfd;
151
152 while (!ivshmem_server_quit) {
153
154 FD_ZERO(&fds);
155 maxfd = 0;
156 ivshmem_server_get_fds(server, &fds, &maxfd);
157
158 ret = select(maxfd, &fds, NULL, NULL, NULL);
159
160 if (ret < 0) {
161 if (errno == EINTR) {
162 continue;
163 }
164
165 fprintf(stderr, "select error: %s\n", strerror(errno));
166 break;
167 }
168 if (ret == 0) {
169 continue;
170 }
171
172 if (ivshmem_server_handle_fds(server, &fds, maxfd) < 0) {
173 fprintf(stderr, "ivshmem_server_handle_fds() failed\n");
174 break;
175 }
176 }
177
178 return ret;
179 }
180
181 static void
ivshmem_server_quit_cb(int signum)182 ivshmem_server_quit_cb(int signum)
183 {
184 ivshmem_server_quit = 1;
185 }
186
187 int
main(int argc,char * argv[])188 main(int argc, char *argv[])
189 {
190 IvshmemServer server;
191 struct sigaction sa, sa_quit;
192 IvshmemServerArgs args = {
193 .verbose = IVSHMEM_SERVER_DEFAULT_VERBOSE,
194 .foreground = IVSHMEM_SERVER_DEFAULT_FOREGROUND,
195 .pid_file = IVSHMEM_SERVER_DEFAULT_PID_FILE,
196 .unix_socket_path = IVSHMEM_SERVER_DEFAULT_UNIX_SOCK_PATH,
197 .shm_path = IVSHMEM_SERVER_DEFAULT_SHM_PATH,
198 .use_shm_open = true,
199 .shm_size = IVSHMEM_SERVER_DEFAULT_SHM_SIZE,
200 .n_vectors = IVSHMEM_SERVER_DEFAULT_N_VECTORS,
201 };
202 int ret = 1;
203
204 /*
205 * Do not remove this notice without adding proper error handling!
206 * Start with handling ivshmem_server_send_one_msg() failure.
207 */
208 printf("*** Example code, do not use in production ***\n");
209
210 /* parse arguments, will exit on error */
211 ivshmem_server_parse_args(&args, argc, argv);
212
213 /* Ignore SIGPIPE, see this link for more info:
214 * http://www.mail-archive.com/libevent-users@monkey.org/msg01606.html */
215 sa.sa_handler = SIG_IGN;
216 sa.sa_flags = 0;
217 if (sigemptyset(&sa.sa_mask) == -1 ||
218 sigaction(SIGPIPE, &sa, 0) == -1) {
219 perror("failed to ignore SIGPIPE; sigaction");
220 goto err;
221 }
222
223 sa_quit.sa_handler = ivshmem_server_quit_cb;
224 sa_quit.sa_flags = 0;
225 if (sigemptyset(&sa_quit.sa_mask) == -1 ||
226 sigaction(SIGTERM, &sa_quit, 0) == -1 ||
227 sigaction(SIGINT, &sa_quit, 0) == -1) {
228 perror("failed to add signal handler; sigaction");
229 goto err;
230 }
231
232 /* init the ivshms structure */
233 if (ivshmem_server_init(&server, args.unix_socket_path,
234 args.shm_path, args.use_shm_open,
235 args.shm_size, args.n_vectors, args.verbose) < 0) {
236 fprintf(stderr, "cannot init server\n");
237 goto err;
238 }
239
240 /* start the ivshmem server (open shm & unix socket) */
241 if (ivshmem_server_start(&server) < 0) {
242 fprintf(stderr, "cannot bind\n");
243 goto err;
244 }
245
246 /* daemonize if asked to */
247 if (!args.foreground) {
248 FILE *fp;
249
250 if (qemu_daemon(1, 1) < 0) {
251 fprintf(stderr, "cannot daemonize: %s\n", strerror(errno));
252 goto err_close;
253 }
254
255 /* write pid file */
256 fp = fopen(args.pid_file, "w");
257 if (fp == NULL) {
258 fprintf(stderr, "cannot write pid file: %s\n", strerror(errno));
259 goto err_close;
260 }
261
262 fprintf(fp, "%d\n", (int) getpid());
263 fclose(fp);
264 }
265
266 ivshmem_server_poll_events(&server);
267 fprintf(stdout, "server disconnected\n");
268 ret = 0;
269
270 err_close:
271 ivshmem_server_close(&server);
272 err:
273 return ret;
274 }
275