1 /* Copyright (C) 2009 Pierre-Marc Fournier
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public
5 * License as published by the Free Software Foundation; either
6 * version 2.1 of the License, or (at your option) any later version.
8 * This library is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 /* API used by UST components to communicate with each other via sockets. */
21 #include <sys/types.h>
24 #include <sys/socket.h>
28 #include <sys/epoll.h>
40 static int mkdir_p(const char *path
, mode_t mode
)
49 tmp
= zmalloc(strlen(path
) + 1);
58 while (*path_p
!= '/') {
64 strncpy(tmp
, path
, path_p
- path
);
65 tmp
[path_p
-path
] = '\0';
66 if (tmp
[path_p
- path
- 1] != '/') {
67 result
= mkdir(tmp
, mode
);
69 if (!(errno
== EEXIST
|| errno
== EACCES
|| errno
== EROFS
)) {
70 /* Then this is a real error */
80 result
= mkdir(path
, mode
);
92 static struct sockaddr_un
* create_sock_addr(const char *name
,
93 size_t *sock_addr_size
)
95 struct sockaddr_un
* addr
;
98 alloc_size
= (size_t) (((struct sockaddr_un
*) 0)->sun_path
) +
101 addr
= malloc(alloc_size
);
103 ERR("allocating addr failed");
107 addr
->sun_family
= AF_UNIX
;
108 strcpy(addr
->sun_path
, name
);
110 *sock_addr_size
= alloc_size
;
115 struct ustcomm_sock
* ustcomm_init_sock(int fd
, int epoll_fd
,
116 struct list_head
*list
)
118 struct epoll_event ev
;
119 struct ustcomm_sock
*sock
;
121 sock
= malloc(sizeof(struct ustcomm_sock
));
123 perror("malloc: couldn't allocate ustcomm_sock");
131 if (epoll_ctl(epoll_fd
, EPOLL_CTL_ADD
, sock
->fd
, &ev
) == -1) {
132 perror("epoll_ctl: failed to add socket\n");
137 sock
->epoll_fd
= epoll_fd
;
139 list_add(&sock
->list
, list
);
141 INIT_LIST_HEAD(&sock
->list
);
147 void ustcomm_del_sock(struct ustcomm_sock
*sock
, int keep_in_epoll
)
149 list_del(&sock
->list
);
150 if (!keep_in_epoll
) {
151 if (epoll_ctl(sock
->epoll_fd
, EPOLL_CTL_DEL
, sock
->fd
, NULL
) == -1) {
152 PERROR("epoll_ctl: failed to delete socket");
159 struct ustcomm_sock
* ustcomm_init_named_socket(const char *name
,
164 size_t sock_addr_size
;
165 struct sockaddr_un
* addr
;
166 struct ustcomm_sock
*sock
;
168 fd
= socket(PF_UNIX
, SOCK_STREAM
, 0);
174 addr
= create_sock_addr(name
, &sock_addr_size
);
176 ERR("allocating addr, UST thread bailing");
180 result
= access(name
, F_OK
);
183 result
= unlink(name
);
185 PERROR("unlink of socket file");
188 DBG("socket already exists; overwriting");
191 result
= bind(fd
, (struct sockaddr
*)addr
, sock_addr_size
);
197 result
= listen(fd
, 1);
203 sock
= ustcomm_init_sock(fd
, epoll_fd
,
206 ERR("failed to create ustcomm_sock");
222 void ustcomm_del_named_sock(struct ustcomm_sock
*sock
,
223 int keep_socket_file
)
227 struct sockaddr dummy
;
228 struct sockaddr_un
*sockaddr
= NULL
;
233 if(!keep_socket_file
) {
235 /* Get the socket name */
236 alloc_size
= sizeof(dummy
);
237 if (getsockname(fd
, &dummy
, (socklen_t
*)&alloc_size
) < 0) {
238 PERROR("getsockname failed");
242 sockaddr
= zmalloc(alloc_size
);
244 ERR("failed to allocate sockaddr");
248 if (getsockname(fd
, sockaddr
, (socklen_t
*)&alloc_size
) < 0) {
249 PERROR("getsockname failed");
254 result
= stat(sockaddr
->sun_path
, &st
);
256 PERROR("stat (%s)", sockaddr
->sun_path
);
260 /* Paranoid check before deleting. */
261 result
= S_ISSOCK(st
.st_mode
);
263 ERR("The socket we are about to delete is not a socket.");
267 result
= unlink(sockaddr
->sun_path
);
277 ustcomm_del_sock(sock
, keep_socket_file
);
281 /* Called by an app to ask the consumer daemon to connect to it. */
283 int ustcomm_request_consumer(pid_t pid
, const char *channel
)
285 int result
, daemon_fd
;
288 char *explicit_daemon_socket_path
, *daemon_path
;
290 explicit_daemon_socket_path
= getenv("UST_DAEMON_SOCKET");
291 if (explicit_daemon_socket_path
) {
292 /* user specified explicitly a socket path */
293 result
= asprintf(&daemon_path
, "%s", explicit_daemon_socket_path
);
295 /* just use the default path */
296 result
= asprintf(&daemon_path
, "%s/ustd", SOCK_DIR
);
299 ERR("string overflow allocating socket name");
303 if (asprintf(&msg
, "collect %d %s", pid
, channel
) < 0) {
304 ERR("ustcomm_request_consumer : asprintf failed (collect %d/%s)",
307 goto free_daemon_path
;
310 result
= ustcomm_connect_path(daemon_path
, &daemon_fd
);
312 WARN("ustcomm_connect_path failed, daemon_path: %s",
318 result
= ustcomm_send_request(daemon_fd
, msg
, NULL
);
320 WARN("ustcomm_send_request failed, daemon path: %s",
334 /* returns 1 to indicate a message was received
335 * returns 0 to indicate no message was received (end of stream)
336 * returns -1 to indicate an error
338 int ustcomm_recv_fd(int sock
,
339 struct ustcomm_header
*header
,
340 char **data
, int *fd
)
344 struct ustcomm_header peek_header
;
347 struct cmsghdr
*cmsg
;
348 char buf
[CMSG_SPACE(sizeof(int))];
350 result
= recv(sock
, &peek_header
, sizeof(peek_header
),
351 MSG_PEEK
| MSG_WAITALL
);
353 if(errno
== ECONNRESET
) {
355 } else if (errno
== EINTR
) {
357 } else if (result
< 0) {
364 memset(&msg
, 0, sizeof(msg
));
366 iov
[0].iov_base
= (char *)header
;
367 iov
[0].iov_len
= sizeof(struct ustcomm_header
);
372 if (peek_header
.size
) {
373 if (peek_header
.size
< 0 || peek_header
.size
> 100) {
374 WARN("big peek header! %d", peek_header
.size
);
376 *data
= malloc(peek_header
.size
);
378 ERR("failed to allocate space for message");
381 iov
[1].iov_base
= (char *)*data
;
382 iov
[1].iov_len
= peek_header
.size
;
387 if (fd
&& peek_header
.fd_included
) {
388 msg
.msg_control
= buf
;
389 msg
.msg_controllen
= sizeof(buf
);
392 result
= recvmsg(sock
, &msg
,
396 if(errno
== ECONNRESET
) {
398 } else if (errno
== EINTR
) {
400 } else if (result
< 0) {
410 if (fd
&& peek_header
.fd_included
) {
411 cmsg
= CMSG_FIRSTHDR(&msg
);
413 while (cmsg
!= NULL
) {
414 if (cmsg
->cmsg_level
== SOL_SOCKET
415 && cmsg
->cmsg_type
== SCM_RIGHTS
) {
416 *fd
= *(int *) CMSG_DATA(cmsg
);
420 cmsg
= CMSG_NXTHDR(&msg
, cmsg
);
423 ERR("Failed to receive file descriptor\n");
430 int ustcomm_recv(int sock
,
431 struct ustcomm_header
*header
,
434 return ustcomm_recv_fd(sock
, header
, data
, NULL
);
438 int recv_message_conn(int sock
, char **msg
)
440 struct ustcomm_header header
;
442 return ustcomm_recv(sock
, &header
, msg
);
445 int ustcomm_send_fd(int sock
,
446 const struct ustcomm_header
*header
,
453 struct cmsghdr
*cmsg
;
454 char buf
[CMSG_SPACE(sizeof(int))];
456 memset(&msg
, 0, sizeof(msg
));
458 iov
[0].iov_base
= (char *)header
;
459 iov
[0].iov_len
= sizeof(struct ustcomm_header
);
465 iov
[1].iov_base
= (char *)data
;
466 iov
[1].iov_len
= header
->size
;
472 if (fd
&& header
->fd_included
) {
473 msg
.msg_control
= buf
;
474 msg
.msg_controllen
= sizeof(buf
);
475 cmsg
= CMSG_FIRSTHDR(&msg
);
476 cmsg
->cmsg_level
= SOL_SOCKET
;
477 cmsg
->cmsg_type
= SCM_RIGHTS
;
478 cmsg
->cmsg_len
= CMSG_LEN(sizeof(int));
479 *(int *) CMSG_DATA(cmsg
) = *fd
;
480 msg
.msg_controllen
= cmsg
->cmsg_len
;
483 result
= sendmsg(sock
, &msg
, MSG_NOSIGNAL
);
484 if (result
< 0 && errno
!= EPIPE
) {
485 PERROR("sendmsg failed");
490 int ustcomm_send(int sock
,
491 const struct ustcomm_header
*header
,
494 return ustcomm_send_fd(sock
, header
, data
, NULL
);
497 int ustcomm_send_reply(char *msg
, int sock
)
500 struct ustcomm_header header
;
502 memset(&header
, 0, sizeof(header
));
504 header
.size
= strlen(msg
) + 1;
506 result
= ustcomm_send(sock
, &header
, msg
);
508 ERR("error in ustcomm_send");
515 int ustcomm_send_req(int sock
,
516 const struct ustcomm_header
*req_header
,
521 struct ustcomm_header res_header
;
523 result
= ustcomm_send(sock
, req_header
, data
);
532 return ustcomm_recv(sock
,
540 * 0: Success, but no reply because recv() returned 0
544 * On error, the error message is printed, except on
545 * ECONNRESET, which is normal when the application dies.
548 int ustcomm_send_request(int sock
, const char *req
, char **reply
)
550 struct ustcomm_header req_header
;
552 req_header
.size
= strlen(req
) + 1;
554 return ustcomm_send_req(sock
,
566 int ustcomm_connect_path(const char *name
, int *connection_fd
)
569 size_t sock_addr_size
;
570 struct sockaddr_un
*addr
;
572 fd
= socket(PF_UNIX
, SOCK_STREAM
, 0);
578 addr
= create_sock_addr(name
, &sock_addr_size
);
580 ERR("allocating addr failed");
584 result
= connect(fd
, (struct sockaddr
*)addr
, sock_addr_size
);
586 PERROR("connect (path=%s)", name
);
605 /* Open a connection to a traceable app.
612 int ustcomm_connect_app(pid_t pid
, int *app_fd
)
618 result
= asprintf(&name
, "%s/%d", SOCK_DIR
, pid
);
620 ERR("failed to allocate socket name");
624 result
= ustcomm_connect_path(name
, app_fd
);
626 ERR("failed to connect to app");
635 int ensure_dir_exists(const char *dir
)
643 result
= stat(dir
, &st
);
644 if(result
== -1 && errno
!= ENOENT
) {
647 else if(result
== -1) {
651 /* mkdir mode to 0777 */
652 result
= mkdir_p(dir
, S_IRWXU
| S_IRWXG
| S_IRWXO
);
654 ERR("executing in recursive creation of directory %s", dir
);
662 /* Used by the daemon to initialize its server so applications
667 static const char *find_tok(const char *str
)
679 static const char *find_sep(const char *str
)
691 int nth_token_is(const char *str
, const char *token
, int tok_no
)
697 for(i
=0; i
<=tok_no
; i
++) {
711 if(end
-start
!= strlen(token
))
714 if(strncmp(start
, token
, end
-start
))
720 char *nth_token(const char *str
, int tok_no
)
722 static char *retval
= NULL
;
727 for(i
=0; i
<=tok_no
; i
++) {
746 if (asprintf(&retval
, "%.*s", (int)(end
-start
), start
) < 0) {
747 ERR("nth_token : asprintf failed (%.*s)",
748 (int)(end
-start
), start
);