Commit | Line | Data |
---|---|---|
67c5b804 MD |
1 | /* |
2 | * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca> | |
15f672f9 | 3 | * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
67c5b804 | 4 | * |
15f672f9 MD |
5 | * This library is free software; you can redistribute it and/or |
6 | * modify it under the terms of the GNU Lesser General Public | |
7 | * License as published by the Free Software Foundation; only | |
8 | * version 2.1 of the License. | |
9 | * | |
10 | * This library is distributed in the hope that it will be useful, | |
67c5b804 | 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
15f672f9 MD |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | * Lesser General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU Lesser General Public | |
16 | * License along with this library; if not, write to the Free Software | |
17 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
67c5b804 MD |
18 | */ |
19 | ||
20 | #define _GNU_SOURCE | |
21 | #include <limits.h> | |
22 | #include <stdio.h> | |
23 | #include <stdlib.h> | |
24 | #include <string.h> | |
25 | #include <sys/socket.h> | |
26 | #include <sys/stat.h> | |
27 | #include <sys/types.h> | |
28 | #include <sys/un.h> | |
29 | #include <unistd.h> | |
30 | #include <assert.h> | |
57773204 | 31 | #include <errno.h> |
11ba4bcb | 32 | #include <fcntl.h> |
67c5b804 | 33 | |
b728d87e | 34 | #include <ust-comm.h> |
67c5b804 MD |
35 | |
36 | /* | |
37 | * Human readable error message. | |
38 | */ | |
57773204 MD |
39 | static const char *ustcomm_readable_code[] = { |
40 | [ USTCOMM_ERR_INDEX(USTCOMM_ERR) ] = "Unknown error", | |
41 | [ USTCOMM_ERR_INDEX(USTCOMM_UND) ] = "Undefined command", | |
42 | [ USTCOMM_ERR_INDEX(USTCOMM_NOT_IMPLEMENTED) ] = "Not implemented", | |
43 | [ USTCOMM_ERR_INDEX(USTCOMM_UNKNOWN_DOMAIN) ] = "Unknown tracing domain", | |
44 | [ USTCOMM_ERR_INDEX(USTCOMM_NO_SESSION) ] = "No session found", | |
45 | [ USTCOMM_ERR_INDEX(USTCOMM_LIST_FAIL) ] = "Unable to list traceable apps", | |
46 | [ USTCOMM_ERR_INDEX(USTCOMM_NO_APPS) ] = "No traceable apps found", | |
47 | [ USTCOMM_ERR_INDEX(USTCOMM_SESS_NOT_FOUND) ] = "Session name not found", | |
48 | [ USTCOMM_ERR_INDEX(USTCOMM_NO_TRACE) ] = "No trace found", | |
49 | [ USTCOMM_ERR_INDEX(USTCOMM_FATAL) ] = "Fatal error of the session daemon", | |
50 | [ USTCOMM_ERR_INDEX(USTCOMM_CREATE_FAIL) ] = "Create trace failed", | |
51 | [ USTCOMM_ERR_INDEX(USTCOMM_START_FAIL) ] = "Start trace failed", | |
52 | [ USTCOMM_ERR_INDEX(USTCOMM_STOP_FAIL) ] = "Stop trace failed", | |
53 | [ USTCOMM_ERR_INDEX(USTCOMM_NO_TRACEABLE) ] = "App is not traceable", | |
54 | [ USTCOMM_ERR_INDEX(USTCOMM_SELECT_SESS) ] = "A session MUST be selected", | |
55 | [ USTCOMM_ERR_INDEX(USTCOMM_EXIST_SESS) ] = "Session name already exist", | |
56 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_NA) ] = "UST tracer not available", | |
57 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_EVENT_EXIST) ] = "UST event already exists", | |
58 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_SESS_FAIL) ] = "UST create session failed", | |
59 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_CHAN_FAIL) ] = "UST create channel failed", | |
60 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_CHAN_NOT_FOUND) ] = "UST channel not found", | |
61 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_CHAN_DISABLE_FAIL) ] = "Disable UST channel failed", | |
62 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_CHAN_ENABLE_FAIL) ] = "Enable UST channel failed", | |
63 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_CONTEXT_FAIL) ] = "Add UST context failed", | |
64 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_ENABLE_FAIL) ] = "Enable UST event failed", | |
65 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_DISABLE_FAIL) ] = "Disable UST event failed", | |
66 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_META_FAIL) ] = "Opening metadata failed", | |
67 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_START_FAIL) ] = "Starting UST trace failed", | |
68 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_STOP_FAIL) ] = "Stoping UST trace failed", | |
69 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_CONSUMER_FAIL) ] = "UST consumer start failed", | |
70 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_STREAM_FAIL) ] = "UST create stream failed", | |
71 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_DIR_FAIL) ] = "UST trace directory creation failed", | |
72 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_DIR_EXIST) ] = "UST trace directory already exist", | |
73 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_NO_SESSION) ] = "No UST session found", | |
74 | [ USTCOMM_ERR_INDEX(USTCOMM_KERN_LIST_FAIL) ] = "Listing UST events failed", | |
75 | [ USTCOMM_ERR_INDEX(USTCONSUMER_COMMAND_SOCK_READY) ] = "UST consumer command socket ready", | |
76 | [ USTCOMM_ERR_INDEX(USTCONSUMER_SUCCESS_RECV_FD) ] = "UST consumer success on receiving fds", | |
77 | [ USTCOMM_ERR_INDEX(USTCONSUMER_ERROR_RECV_FD) ] = "UST consumer error on receiving fds", | |
78 | [ USTCOMM_ERR_INDEX(USTCONSUMER_POLL_ERROR) ] = "UST consumer error in polling thread", | |
79 | [ USTCOMM_ERR_INDEX(USTCONSUMER_POLL_NVAL) ] = "UST consumer polling on closed fd", | |
80 | [ USTCOMM_ERR_INDEX(USTCONSUMER_POLL_HUP) ] = "UST consumer all fd hung up", | |
81 | [ USTCOMM_ERR_INDEX(USTCONSUMER_EXIT_SUCCESS) ] = "UST consumer exiting normally", | |
82 | [ USTCOMM_ERR_INDEX(USTCONSUMER_EXIT_FAILURE) ] = "UST consumer exiting on error", | |
83 | [ USTCOMM_ERR_INDEX(USTCONSUMER_OUTFD_ERROR) ] = "UST consumer error opening the tracefile", | |
84 | [ USTCOMM_ERR_INDEX(USTCONSUMER_SPLICE_EBADF) ] = "UST consumer splice EBADF", | |
85 | [ USTCOMM_ERR_INDEX(USTCONSUMER_SPLICE_EINVAL) ] = "UST consumer splice EINVAL", | |
86 | [ USTCOMM_ERR_INDEX(USTCONSUMER_SPLICE_ENOMEM) ] = "UST consumer splice ENOMEM", | |
87 | [ USTCOMM_ERR_INDEX(USTCONSUMER_SPLICE_ESPIPE) ] = "UST consumer splice ESPIPE", | |
88 | [ USTCOMM_ERR_INDEX(USTCOMM_NO_EVENT) ] = "Event not found", | |
67c5b804 MD |
89 | }; |
90 | ||
91 | /* | |
92 | * lttcom_get_readable_code | |
93 | * | |
94 | * Return ptr to string representing a human readable | |
57773204 | 95 | * error code from the ustcomm_return_code enum. |
67c5b804 | 96 | */ |
57773204 | 97 | const char *ustcomm_get_readable_code(int code) |
67c5b804 | 98 | { |
57773204 MD |
99 | if (code == USTCOMM_OK) { |
100 | return "Success"; | |
67c5b804 | 101 | } |
57773204 MD |
102 | if (code >= USTCOMM_ERR && code < USTCOMM_NR) { |
103 | return ustcomm_readable_code[USTCOMM_ERR_INDEX(code)]; | |
104 | } | |
105 | return strerror(code); | |
67c5b804 MD |
106 | } |
107 | ||
108 | /* | |
57773204 | 109 | * ustcomm_connect_unix_sock |
67c5b804 MD |
110 | * |
111 | * Connect to unix socket using the path name. | |
112 | */ | |
57773204 | 113 | int ustcomm_connect_unix_sock(const char *pathname) |
67c5b804 MD |
114 | { |
115 | struct sockaddr_un sun; | |
116 | int fd; | |
117 | int ret; | |
118 | ||
204d45df MD |
119 | /* |
120 | * libust threads require the close-on-exec flag for all | |
121 | * resources so it does not leak file descriptors upon exec. | |
122 | */ | |
11ba4bcb | 123 | fd = socket(PF_UNIX, SOCK_STREAM, 0); |
67c5b804 MD |
124 | if (fd < 0) { |
125 | perror("socket"); | |
126 | ret = fd; | |
127 | goto error; | |
128 | } | |
11ba4bcb MD |
129 | ret = fcntl(fd, F_SETFD, FD_CLOEXEC); |
130 | if (ret < 0) { | |
131 | perror("fcntl"); | |
132 | goto error_fcntl; | |
133 | } | |
67c5b804 MD |
134 | |
135 | memset(&sun, 0, sizeof(sun)); | |
136 | sun.sun_family = AF_UNIX; | |
137 | strncpy(sun.sun_path, pathname, sizeof(sun.sun_path)); | |
138 | sun.sun_path[sizeof(sun.sun_path) - 1] = '\0'; | |
139 | ||
140 | ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun)); | |
141 | if (ret < 0) { | |
142 | /* | |
143 | * Don't print message on connect error, because connect | |
144 | * is used in normal execution to detect if sessiond is | |
145 | * alive. | |
146 | */ | |
147 | goto error_connect; | |
148 | } | |
149 | ||
150 | return fd; | |
151 | ||
152 | error_connect: | |
11ba4bcb | 153 | error_fcntl: |
67c5b804 MD |
154 | close(fd); |
155 | error: | |
156 | return ret; | |
157 | } | |
158 | ||
159 | /* | |
57773204 | 160 | * ustcomm_accept_unix_sock |
67c5b804 MD |
161 | * |
162 | * Do an accept(2) on the sock and return the | |
163 | * new file descriptor. The socket MUST be bind(2) before. | |
164 | */ | |
57773204 | 165 | int ustcomm_accept_unix_sock(int sock) |
67c5b804 MD |
166 | { |
167 | int new_fd; | |
168 | struct sockaddr_un sun; | |
169 | socklen_t len = 0; | |
170 | ||
171 | /* Blocking call */ | |
172 | new_fd = accept(sock, (struct sockaddr *) &sun, &len); | |
173 | if (new_fd < 0) { | |
174 | perror("accept"); | |
175 | goto error; | |
176 | } | |
177 | ||
178 | return new_fd; | |
179 | ||
180 | error: | |
181 | return -1; | |
182 | } | |
183 | ||
184 | /* | |
57773204 | 185 | * ustcomm_create_unix_sock |
67c5b804 MD |
186 | * |
187 | * Creates a AF_UNIX local socket using pathname | |
188 | * bind the socket upon creation and return the fd. | |
189 | */ | |
57773204 | 190 | int ustcomm_create_unix_sock(const char *pathname) |
67c5b804 MD |
191 | { |
192 | struct sockaddr_un sun; | |
193 | int fd; | |
194 | int ret = -1; | |
195 | ||
196 | /* Create server socket */ | |
197 | if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) { | |
198 | perror("socket"); | |
199 | goto error; | |
200 | } | |
201 | ||
202 | memset(&sun, 0, sizeof(sun)); | |
203 | sun.sun_family = AF_UNIX; | |
204 | strncpy(sun.sun_path, pathname, sizeof(sun.sun_path)); | |
205 | sun.sun_path[sizeof(sun.sun_path) - 1] = '\0'; | |
206 | ||
207 | /* Unlink the old file if present */ | |
208 | (void) unlink(pathname); | |
209 | ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun)); | |
210 | if (ret < 0) { | |
211 | perror("bind"); | |
212 | goto error; | |
213 | } | |
214 | ||
215 | return fd; | |
216 | ||
217 | error: | |
218 | return ret; | |
219 | } | |
220 | ||
221 | /* | |
57773204 | 222 | * ustcomm_listen_unix_sock |
67c5b804 | 223 | * |
e41474be | 224 | * Make the socket listen using LTTNG_UST_COMM_MAX_LISTEN. |
67c5b804 | 225 | */ |
57773204 | 226 | int ustcomm_listen_unix_sock(int sock) |
67c5b804 MD |
227 | { |
228 | int ret; | |
229 | ||
e41474be | 230 | ret = listen(sock, LTTNG_UST_COMM_MAX_LISTEN); |
67c5b804 MD |
231 | if (ret < 0) { |
232 | perror("listen"); | |
233 | } | |
234 | ||
235 | return ret; | |
236 | } | |
237 | ||
238 | /* | |
57773204 | 239 | * ustcomm_recv_unix_sock |
67c5b804 MD |
240 | * |
241 | * Receive data of size len in put that data into | |
242 | * the buf param. Using recvmsg API. | |
243 | * Return the size of received data. | |
244 | */ | |
57773204 | 245 | ssize_t ustcomm_recv_unix_sock(int sock, void *buf, size_t len) |
67c5b804 | 246 | { |
913b87f1 | 247 | struct msghdr msg; |
67c5b804 MD |
248 | struct iovec iov[1]; |
249 | ssize_t ret = -1; | |
250 | ||
913b87f1 MD |
251 | memset(&msg, 0, sizeof(msg)); |
252 | ||
67c5b804 MD |
253 | iov[0].iov_base = buf; |
254 | iov[0].iov_len = len; | |
255 | msg.msg_iov = iov; | |
256 | msg.msg_iovlen = 1; | |
257 | ||
7e3cfcbe MD |
258 | do { |
259 | ret = recvmsg(sock, &msg, 0); | |
260 | } while (ret < 0 && errno == EINTR); | |
45d35b9f | 261 | if (ret < 0 && errno != EPIPE) { |
67c5b804 MD |
262 | perror("recvmsg"); |
263 | } | |
264 | ||
265 | return ret; | |
266 | } | |
267 | ||
268 | /* | |
57773204 | 269 | * ustcomm_send_unix_sock |
67c5b804 MD |
270 | * |
271 | * Send buf data of size len. Using sendmsg API. | |
272 | * Return the size of sent data. | |
273 | */ | |
57773204 | 274 | ssize_t ustcomm_send_unix_sock(int sock, void *buf, size_t len) |
67c5b804 | 275 | { |
913b87f1 | 276 | struct msghdr msg; |
67c5b804 MD |
277 | struct iovec iov[1]; |
278 | ssize_t ret = -1; | |
279 | ||
913b87f1 MD |
280 | memset(&msg, 0, sizeof(msg)); |
281 | ||
67c5b804 MD |
282 | iov[0].iov_base = buf; |
283 | iov[0].iov_len = len; | |
284 | msg.msg_iov = iov; | |
285 | msg.msg_iovlen = 1; | |
286 | ||
1ea11eab MD |
287 | /* |
288 | * Using the MSG_NOSIGNAL when sending data from sessiond to | |
289 | * libust, so libust does not receive an unhandled SIGPIPE or | |
290 | * SIGURG. The sessiond receiver side can be made more resilient | |
291 | * by ignoring SIGPIPE, but we don't have this luxury on the | |
292 | * libust side. | |
293 | */ | |
51d9d699 MD |
294 | do { |
295 | ret = sendmsg(sock, &msg, MSG_NOSIGNAL); | |
296 | } while (ret < 0 && errno == EINTR); | |
45d35b9f | 297 | if (ret < 0 && errno != EPIPE) { |
67c5b804 MD |
298 | perror("sendmsg"); |
299 | } | |
300 | ||
301 | return ret; | |
302 | } | |
303 | ||
304 | /* | |
57773204 | 305 | * ustcomm_close_unix_sock |
67c5b804 MD |
306 | * |
307 | * Shutdown cleanly a unix socket. | |
308 | */ | |
57773204 | 309 | int ustcomm_close_unix_sock(int sock) |
67c5b804 MD |
310 | { |
311 | int ret; | |
312 | ||
e6973a89 | 313 | ret = close(sock); |
67c5b804 | 314 | if (ret < 0) { |
e6973a89 | 315 | perror("close"); |
67c5b804 MD |
316 | } |
317 | ||
318 | return ret; | |
319 | } | |
320 | ||
321 | /* | |
57773204 | 322 | * ustcomm_send_fds_unix_sock |
67c5b804 MD |
323 | * |
324 | * Send multiple fds on a unix socket. | |
325 | */ | |
57773204 | 326 | ssize_t ustcomm_send_fds_unix_sock(int sock, void *buf, int *fds, size_t nb_fd, size_t len) |
67c5b804 | 327 | { |
913b87f1 | 328 | struct msghdr msg; |
67c5b804 MD |
329 | struct cmsghdr *cmptr; |
330 | struct iovec iov[1]; | |
331 | ssize_t ret = -1; | |
332 | unsigned int sizeof_fds = nb_fd * sizeof(int); | |
333 | char tmp[CMSG_SPACE(sizeof_fds)]; | |
334 | ||
913b87f1 MD |
335 | memset(&msg, 0, sizeof(msg)); |
336 | ||
67c5b804 MD |
337 | /* |
338 | * Note: the consumerd receiver only supports receiving one FD per | |
339 | * message. | |
340 | */ | |
341 | assert(nb_fd == 1); | |
342 | ||
343 | msg.msg_control = (caddr_t)tmp; | |
344 | msg.msg_controllen = CMSG_LEN(sizeof_fds); | |
345 | ||
346 | cmptr = CMSG_FIRSTHDR(&msg); | |
347 | cmptr->cmsg_level = SOL_SOCKET; | |
348 | cmptr->cmsg_type = SCM_RIGHTS; | |
349 | cmptr->cmsg_len = CMSG_LEN(sizeof_fds); | |
350 | memcpy(CMSG_DATA(cmptr), fds, sizeof_fds); | |
351 | /* Sum of the length of all control messages in the buffer: */ | |
352 | msg.msg_controllen = cmptr->cmsg_len; | |
353 | ||
354 | iov[0].iov_base = buf; | |
355 | iov[0].iov_len = len; | |
356 | msg.msg_iov = iov; | |
357 | msg.msg_iovlen = 1; | |
358 | ||
51d9d699 MD |
359 | do { |
360 | ret = sendmsg(sock, &msg, MSG_NOSIGNAL); | |
361 | } while (ret < 0 && errno == EINTR); | |
45d35b9f | 362 | if (ret < 0 && errno != EPIPE) { |
67c5b804 MD |
363 | perror("sendmsg"); |
364 | } | |
365 | ||
366 | return ret; | |
367 | } | |
57773204 MD |
368 | |
369 | int ustcomm_send_app_msg(int sock, struct ustcomm_ust_msg *lum) | |
370 | { | |
371 | ssize_t len; | |
372 | ||
373 | len = ustcomm_send_unix_sock(sock, lum, sizeof(*lum)); | |
374 | switch (len) { | |
375 | case sizeof(*lum): | |
57773204 MD |
376 | break; |
377 | case -1: | |
378 | if (errno == ECONNRESET) { | |
c1ee6c90 | 379 | fprintf(stderr, "remote end closed connection\n"); |
57773204 MD |
380 | return 0; |
381 | } | |
382 | return -1; | |
383 | default: | |
c1ee6c90 | 384 | fprintf(stderr, "incorrect message size: %zd\n", len); |
57773204 MD |
385 | return -1; |
386 | } | |
387 | return 0; | |
388 | } | |
389 | ||
390 | int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur, | |
391 | uint32_t expected_handle, uint32_t expected_cmd) | |
392 | { | |
393 | ssize_t len; | |
394 | ||
395 | memset(lur, 0, sizeof(*lur)); | |
396 | len = ustcomm_recv_unix_sock(sock, lur, sizeof(*lur)); | |
397 | switch (len) { | |
398 | case 0: /* orderly shutdown */ | |
57773204 MD |
399 | return -EINVAL; |
400 | case sizeof(*lur): | |
57773204 | 401 | if (lur->handle != expected_handle) { |
c1ee6c90 | 402 | fprintf(stderr, "Unexpected result message handle\n"); |
57773204 MD |
403 | return -EINVAL; |
404 | } | |
405 | ||
406 | if (lur->cmd != expected_cmd) { | |
c1ee6c90 | 407 | fprintf(stderr, "Unexpected result message command\n"); |
57773204 MD |
408 | return -EINVAL; |
409 | } | |
410 | if (lur->ret_code != USTCOMM_OK) { | |
e55f988e MD |
411 | /* |
412 | * Some errors are normal.. we should put this | |
413 | * in a debug level message... | |
414 | * fprintf(stderr, "remote operation failed with code %d.\n", | |
415 | * lur->ret_code); | |
416 | */ | |
57773204 MD |
417 | return lur->ret_code; |
418 | } | |
419 | return 0; | |
420 | case -1: | |
421 | if (errno == ECONNRESET) { | |
c1ee6c90 | 422 | fprintf(stderr, "remote end closed connection\n"); |
57773204 MD |
423 | return -EINVAL; |
424 | } | |
425 | return -1; | |
426 | default: | |
c1ee6c90 | 427 | fprintf(stderr, "incorrect message size: %zd\n", len); |
57773204 MD |
428 | return len > 0 ? -1 : len; |
429 | } | |
430 | } | |
431 | ||
432 | int ustcomm_send_app_cmd(int sock, | |
433 | struct ustcomm_ust_msg *lum, | |
434 | struct ustcomm_ust_reply *lur) | |
435 | { | |
436 | int ret; | |
437 | ||
438 | ret = ustcomm_send_app_msg(sock, lum); | |
439 | if (ret) | |
440 | return ret; | |
441 | ret = ustcomm_recv_app_reply(sock, lur, lum->handle, lum->cmd); | |
442 | if (ret) | |
443 | return ret; | |
444 | return 0; | |
445 | } | |
446 | ||
447 | ||
448 | /* | |
449 | * Receives a single fd from socket. | |
450 | * | |
451 | * Returns the size of received data | |
452 | */ | |
453 | int ustcomm_recv_fd(int sock) | |
454 | { | |
455 | struct iovec iov[1]; | |
456 | int ret = 0; | |
457 | int data_fd; | |
458 | struct cmsghdr *cmsg; | |
459 | char recv_fd[CMSG_SPACE(sizeof(int))]; | |
913b87f1 | 460 | struct msghdr msg; |
57773204 MD |
461 | union { |
462 | unsigned char vc[4]; | |
463 | int vi; | |
464 | } tmp; | |
465 | int i; | |
466 | ||
913b87f1 MD |
467 | memset(&msg, 0, sizeof(msg)); |
468 | ||
57773204 MD |
469 | /* Prepare to receive the structures */ |
470 | iov[0].iov_base = &data_fd; | |
471 | iov[0].iov_len = sizeof(data_fd); | |
472 | msg.msg_iov = iov; | |
473 | msg.msg_iovlen = 1; | |
474 | msg.msg_control = recv_fd; | |
475 | msg.msg_controllen = sizeof(recv_fd); | |
476 | ||
7e3cfcbe MD |
477 | do { |
478 | ret = recvmsg(sock, &msg, 0); | |
479 | } while (ret < 0 && errno == EINTR); | |
480 | if (ret < 0) { | |
45d35b9f MD |
481 | if (errno != EPIPE) { |
482 | perror("recvmsg"); | |
483 | } | |
57773204 MD |
484 | goto end; |
485 | } | |
486 | if (ret != sizeof(data_fd)) { | |
7210fb23 | 487 | fprintf(stderr, "Received %d bytes, expected %zd", ret, sizeof(data_fd)); |
57773204 MD |
488 | goto end; |
489 | } | |
490 | cmsg = CMSG_FIRSTHDR(&msg); | |
491 | if (!cmsg) { | |
c1ee6c90 | 492 | fprintf(stderr, "Invalid control message header\n"); |
57773204 MD |
493 | ret = -1; |
494 | goto end; | |
495 | } | |
496 | if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) { | |
c1ee6c90 | 497 | fprintf(stderr, "Didn't received any fd\n"); |
57773204 MD |
498 | ret = -1; |
499 | goto end; | |
500 | } | |
501 | /* this is our fd */ | |
502 | for (i = 0; i < sizeof(int); i++) | |
503 | tmp.vc[i] = CMSG_DATA(cmsg)[i]; | |
504 | ret = tmp.vi; | |
e55f988e MD |
505 | /* |
506 | * Useful for fd leak debug. | |
507 | * fprintf(stderr, "received fd %d\n", ret); | |
508 | */ | |
57773204 MD |
509 | end: |
510 | return ret; | |
511 | } |