aboutsummaryrefslogtreecommitdiff
path: root/contrib/ivshmem-server/main.c
blob: 197c79c57ec2eda492e51cb08896b58a009f0c46 (plain)
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
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
/*
 * Copyright 6WIND S.A., 2014
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or
 * (at your option) any later version.  See the COPYING file in the
 * top-level directory.
 */

#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/cutils.h"
#include "qemu/option.h"
#include "ivshmem-server.h"

#define IVSHMEM_SERVER_DEFAULT_VERBOSE        0
#define IVSHMEM_SERVER_DEFAULT_FOREGROUND     0
#define IVSHMEM_SERVER_DEFAULT_PID_FILE       "/var/run/ivshmem-server.pid"
#define IVSHMEM_SERVER_DEFAULT_UNIX_SOCK_PATH "/tmp/ivshmem_socket"
#define IVSHMEM_SERVER_DEFAULT_SHM_PATH       "ivshmem"
#define IVSHMEM_SERVER_DEFAULT_SHM_SIZE       (4*1024*1024)
#define IVSHMEM_SERVER_DEFAULT_N_VECTORS      1

/* used to quit on signal SIGTERM */
static int ivshmem_server_quit;

/* arguments given by the user */
typedef struct IvshmemServerArgs {
    bool verbose;
    bool foreground;
    const char *pid_file;
    const char *unix_socket_path;
    const char *shm_path;
    bool use_shm_open;
    uint64_t shm_size;
    unsigned n_vectors;
} IvshmemServerArgs;

static void
ivshmem_server_usage(const char *progname)
{
    printf("Usage: %s [OPTION]...\n"
           "  -h: show this help\n"
           "  -v: verbose mode\n"
           "  -F: foreground mode (default is to daemonize)\n"
           "  -p <pid-file>: path to the PID file (used in daemon mode only)\n"
           "     default " IVSHMEM_SERVER_DEFAULT_PID_FILE "\n"
           "  -S <unix-socket-path>: path to the unix socket to listen to\n"
           "     default " IVSHMEM_SERVER_DEFAULT_UNIX_SOCK_PATH "\n"
           "  -M <shm-name>: POSIX shared memory object to use\n"
           "     default " IVSHMEM_SERVER_DEFAULT_SHM_PATH "\n"
           "  -m <dir-name>: where to create shared memory\n"
           "  -l <size>: size of shared memory in bytes\n"
           "     suffixes K, M and G can be used, e.g. 1K means 1024\n"
           "     default %u\n"
           "  -n <nvectors>: number of vectors\n"
           "     default %u\n",
           progname, IVSHMEM_SERVER_DEFAULT_SHM_SIZE,
           IVSHMEM_SERVER_DEFAULT_N_VECTORS);
}

static void
ivshmem_server_help(const char *progname)
{
    fprintf(stderr, "Try '%s -h' for more information.\n", progname);
}

/* parse the program arguments, exit on error */
static void
ivshmem_server_parse_args(IvshmemServerArgs *args, int argc, char *argv[])
{
    int c;
    unsigned long long v;
    Error *err = NULL;

    while ((c = getopt(argc, argv, "hvFp:S:m:M:l:n:")) != -1) {

        switch (c) {
        case 'h': /* help */
            ivshmem_server_usage(argv[0]);
            exit(0);
            break;

        case 'v': /* verbose */
            args->verbose = 1;
            break;

        case 'F': /* foreground */
            args->foreground = 1;
            break;

        case 'p': /* pid file */
            args->pid_file = optarg;
            break;

        case 'S': /* unix socket path */
            args->unix_socket_path = optarg;
            break;

        case 'M': /* shm name */
        case 'm': /* dir name */
            args->shm_path = optarg;
            args->use_shm_open = c == 'M';
            break;

        case 'l': /* shm size */
            parse_option_size("shm_size", optarg, &args->shm_size, &err);
            if (err) {
                error_report_err(err);
                ivshmem_server_help(argv[0]);
                exit(1);
            }
            break;

        case 'n': /* number of vectors */
            if (parse_uint_full(optarg, &v, 0) < 0) {
                fprintf(stderr, "cannot parse n_vectors\n");
                ivshmem_server_help(argv[0]);
                exit(1);
            }
            args->n_vectors = v;
            break;

        default:
            ivshmem_server_usage(argv[0]);
            exit(1);
            break;
        }
    }

    if (args->n_vectors > IVSHMEM_SERVER_MAX_VECTORS) {
        fprintf(stderr, "too many requested vectors (max is %d)\n",
                IVSHMEM_SERVER_MAX_VECTORS);
        ivshmem_server_help(argv[0]);
        exit(1);
    }

    if (args->verbose == 1 && args->foreground == 0) {
        fprintf(stderr, "cannot use verbose in daemon mode\n");
        ivshmem_server_help(argv[0]);
        exit(1);
    }
}

/* wait for events on listening server unix socket and connected client
 * sockets */
static int
ivshmem_server_poll_events(IvshmemServer *server)
{
    fd_set fds;
    int ret = 0, maxfd;

    while (!ivshmem_server_quit) {

        FD_ZERO(&fds);
        maxfd = 0;
        ivshmem_server_get_fds(server, &fds, &maxfd);

        ret = select(maxfd, &fds, NULL, NULL, NULL);

        if (ret < 0) {
            if (errno == EINTR) {
                continue;
            }

            fprintf(stderr, "select error: %s\n", strerror(errno));
            break;
        }
        if (ret == 0) {
            continue;
        }

        if (ivshmem_server_handle_fds(server, &fds, maxfd) < 0) {
            fprintf(stderr, "ivshmem_server_handle_fds() failed\n");
            break;
        }
    }

    return ret;
}

static void
ivshmem_server_quit_cb(int signum)
{
    ivshmem_server_quit = 1;
}

int
main(int argc, char *argv[])
{
    IvshmemServer server;
    struct sigaction sa, sa_quit;
    IvshmemServerArgs args = {
        .verbose = IVSHMEM_SERVER_DEFAULT_VERBOSE,
        .foreground = IVSHMEM_SERVER_DEFAULT_FOREGROUND,
        .pid_file = IVSHMEM_SERVER_DEFAULT_PID_FILE,
        .unix_socket_path = IVSHMEM_SERVER_DEFAULT_UNIX_SOCK_PATH,
        .shm_path = IVSHMEM_SERVER_DEFAULT_SHM_PATH,
        .use_shm_open = true,
        .shm_size = IVSHMEM_SERVER_DEFAULT_SHM_SIZE,
        .n_vectors = IVSHMEM_SERVER_DEFAULT_N_VECTORS,
    };
    int ret = 1;

    /*
     * Do not remove this notice without adding proper error handling!
     * Start with handling ivshmem_server_send_one_msg() failure.
     */
    printf("*** Example code, do not use in production ***\n");

    /* parse arguments, will exit on error */
    ivshmem_server_parse_args(&args, argc, argv);

    /* Ignore SIGPIPE, see this link for more info:
     * http://www.mail-archive.com/libevent-users@monkey.org/msg01606.html */
    sa.sa_handler = SIG_IGN;
    sa.sa_flags = 0;
    if (sigemptyset(&sa.sa_mask) == -1 ||
        sigaction(SIGPIPE, &sa, 0) == -1) {
        perror("failed to ignore SIGPIPE; sigaction");
        goto err;
    }

    sa_quit.sa_handler = ivshmem_server_quit_cb;
    sa_quit.sa_flags = 0;
    if (sigemptyset(&sa_quit.sa_mask) == -1 ||
        sigaction(SIGTERM, &sa_quit, 0) == -1) {
        perror("failed to add SIGTERM handler; sigaction");
        goto err;
    }

    /* init the ivshms structure */
    if (ivshmem_server_init(&server, args.unix_socket_path,
                            args.shm_path, args.use_shm_open,
                            args.shm_size, args.n_vectors, args.verbose) < 0) {
        fprintf(stderr, "cannot init server\n");
        goto err;
    }

    /* start the ivshmem server (open shm & unix socket) */
    if (ivshmem_server_start(&server) < 0) {
        fprintf(stderr, "cannot bind\n");
        goto err;
    }

    /* daemonize if asked to */
    if (!args.foreground) {
        FILE *fp;

        if (qemu_daemon(1, 1) < 0) {
            fprintf(stderr, "cannot daemonize: %s\n", strerror(errno));
            goto err_close;
        }

        /* write pid file */
        fp = fopen(args.pid_file, "w");
        if (fp == NULL) {
            fprintf(stderr, "cannot write pid file: %s\n", strerror(errno));
            goto err_close;
        }

        fprintf(fp, "%d\n", (int) getpid());
        fclose(fp);
    }

    ivshmem_server_poll_events(&server);
    fprintf(stdout, "server disconnected\n");
    ret = 0;

err_close:
    ivshmem_server_close(&server);
err:
    return ret;
}