| 1 | /* Copyright (C) 2009 Pierre-Marc Fournier |
| 2 | * |
| 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. |
| 7 | * |
| 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. |
| 12 | * |
| 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 |
| 16 | */ |
| 17 | |
| 18 | /* API used by UST components to communicate with each other via sockets. */ |
| 19 | |
| 20 | #define _GNU_SOURCE |
| 21 | #include <sys/types.h> |
| 22 | #include <signal.h> |
| 23 | #include <errno.h> |
| 24 | #include <sys/socket.h> |
| 25 | #include <sys/un.h> |
| 26 | #include <unistd.h> |
| 27 | #include <poll.h> |
| 28 | #include <sys/stat.h> |
| 29 | |
| 30 | #include <stdio.h> |
| 31 | #include <stdlib.h> |
| 32 | #include <string.h> |
| 33 | #include <execinfo.h> |
| 34 | |
| 35 | #include "ustcomm.h" |
| 36 | #include "usterr.h" |
| 37 | #include "share.h" |
| 38 | #include "multipoll.h" |
| 39 | |
| 40 | #define UNIX_PATH_MAX 108 |
| 41 | |
| 42 | static int mkdir_p(const char *path, mode_t mode) |
| 43 | { |
| 44 | const char *path_p; |
| 45 | char *tmp; |
| 46 | |
| 47 | int retval = 0; |
| 48 | int result; |
| 49 | mode_t old_umask; |
| 50 | |
| 51 | tmp = malloc(strlen(path) + 1); |
| 52 | if (tmp == NULL) |
| 53 | return -1; |
| 54 | |
| 55 | /* skip first / */ |
| 56 | path_p = path+1; |
| 57 | |
| 58 | old_umask = umask(0); |
| 59 | for(;;) { |
| 60 | while (*path_p != '/') { |
| 61 | if(*path_p == 0) |
| 62 | break; |
| 63 | ++path_p; |
| 64 | } |
| 65 | if (*path_p == '/') { |
| 66 | strncpy(tmp, path, path_p - path); |
| 67 | tmp[path_p-path] = '\0'; |
| 68 | if (tmp[path_p - path - 1] != '/') { |
| 69 | result = mkdir(tmp, mode); |
| 70 | if(result == -1) { |
| 71 | if (!(errno == EEXIST || errno == EACCES || errno == EROFS)) { |
| 72 | /* Then this is a real error */ |
| 73 | retval = -1; |
| 74 | break; |
| 75 | } |
| 76 | } |
| 77 | } |
| 78 | /* pass / */ |
| 79 | path_p++; |
| 80 | } else { |
| 81 | /* last component */ |
| 82 | result = mkdir(path, mode); |
| 83 | if (result == -1) |
| 84 | retval = -1; |
| 85 | break; |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | free(tmp); |
| 90 | umask(old_umask); |
| 91 | return retval; |
| 92 | } |
| 93 | |
| 94 | static int signal_process(pid_t pid) |
| 95 | { |
| 96 | return 0; |
| 97 | } |
| 98 | |
| 99 | void ustcomm_init_connection(struct ustcomm_connection *conn) |
| 100 | { |
| 101 | conn->recv_buf = NULL; |
| 102 | conn->recv_buf_size = 0; |
| 103 | conn->recv_buf_alloc = 0; |
| 104 | } |
| 105 | |
| 106 | int pid_is_online(pid_t pid) { |
| 107 | return 1; |
| 108 | } |
| 109 | |
| 110 | /* Send a message |
| 111 | * |
| 112 | * @fd: file descriptor to send to |
| 113 | * @msg: a null-terminated string containing the message to send |
| 114 | * |
| 115 | * Return value: |
| 116 | * -1: error |
| 117 | * 0: connection closed |
| 118 | * 1: success |
| 119 | */ |
| 120 | |
| 121 | static int send_message_fd(int fd, const char *msg) |
| 122 | { |
| 123 | int result; |
| 124 | |
| 125 | /* Send including the final \0 */ |
| 126 | result = patient_send(fd, msg, strlen(msg)+1, MSG_NOSIGNAL); |
| 127 | if(result == -1) { |
| 128 | if(errno != EPIPE) |
| 129 | PERROR("send"); |
| 130 | return -1; |
| 131 | } |
| 132 | else if(result == 0) { |
| 133 | return 0; |
| 134 | } |
| 135 | |
| 136 | DBG("sent message \"%s\"", msg); |
| 137 | return 1; |
| 138 | } |
| 139 | |
| 140 | /* Called by an app to ask the consumer daemon to connect to it. */ |
| 141 | |
| 142 | int ustcomm_request_consumer(pid_t pid, const char *channel) |
| 143 | { |
| 144 | char path[UNIX_PATH_MAX]; |
| 145 | int result; |
| 146 | char *msg=NULL; |
| 147 | int retval = 0; |
| 148 | struct ustcomm_connection conn; |
| 149 | char *explicit_daemon_socket_path; |
| 150 | |
| 151 | explicit_daemon_socket_path = getenv("UST_DAEMON_SOCKET"); |
| 152 | if(explicit_daemon_socket_path) { |
| 153 | /* user specified explicitly a socket path */ |
| 154 | result = snprintf(path, UNIX_PATH_MAX, "%s", explicit_daemon_socket_path); |
| 155 | } |
| 156 | else { |
| 157 | /* just use the default path */ |
| 158 | result = snprintf(path, UNIX_PATH_MAX, "%s/ustd", SOCK_DIR); |
| 159 | } |
| 160 | |
| 161 | if(result >= UNIX_PATH_MAX) { |
| 162 | ERR("string overflow allocating socket name"); |
| 163 | return -1; |
| 164 | } |
| 165 | |
| 166 | asprintf(&msg, "collect %d %s", pid, channel); |
| 167 | |
| 168 | /* don't signal it because it's the daemon */ |
| 169 | result = ustcomm_connect_path(path, &conn, -1); |
| 170 | if(result == -1) { |
| 171 | WARN("ustcomm_connect_path failed"); |
| 172 | retval = -1; |
| 173 | goto del_string; |
| 174 | } |
| 175 | |
| 176 | result = ustcomm_send_request(&conn, msg, NULL); |
| 177 | if(result == -1) { |
| 178 | WARN("ustcomm_send_request failed"); |
| 179 | retval = -1; |
| 180 | goto disconnect; |
| 181 | } |
| 182 | |
| 183 | disconnect: |
| 184 | ustcomm_disconnect(&conn); |
| 185 | del_string: |
| 186 | free(msg); |
| 187 | |
| 188 | return retval; |
| 189 | } |
| 190 | |
| 191 | /* returns 1 to indicate a message was received |
| 192 | * returns 0 to indicate no message was received (end of stream) |
| 193 | * returns -1 to indicate an error |
| 194 | */ |
| 195 | |
| 196 | #define RECV_INCREMENT 1000 |
| 197 | #define RECV_INITIAL_BUF_SIZE 10 |
| 198 | |
| 199 | static int recv_message_fd(int fd, char **recv_buf, int *recv_buf_size, int *recv_buf_alloc, char **msg) |
| 200 | { |
| 201 | int result; |
| 202 | |
| 203 | /* 1. Check if there is a message in the buf */ |
| 204 | /* 2. If not, do: |
| 205 | 2.1 receive chunk and put it in buffer |
| 206 | 2.2 process full message if there is one |
| 207 | -- while no message arrived |
| 208 | */ |
| 209 | |
| 210 | for(;;) { |
| 211 | int i; |
| 212 | int nulfound = 0; |
| 213 | |
| 214 | /* Search for full message in buffer */ |
| 215 | for(i=0; i<*recv_buf_size; i++) { |
| 216 | if((*recv_buf)[i] == '\0') { |
| 217 | nulfound = 1; |
| 218 | break; |
| 219 | } |
| 220 | } |
| 221 | |
| 222 | /* Process found message */ |
| 223 | if(nulfound == 1) { |
| 224 | char *newbuf; |
| 225 | |
| 226 | if(i == 0) { |
| 227 | /* problem */ |
| 228 | WARN("received empty message"); |
| 229 | } |
| 230 | *msg = strndup(*recv_buf, i); |
| 231 | |
| 232 | /* Remove processed message from buffer */ |
| 233 | newbuf = (char *) malloc(*recv_buf_size - (i+1)); |
| 234 | memcpy(newbuf, *recv_buf + (i+1), *recv_buf_size - (i+1)); |
| 235 | free(*recv_buf); |
| 236 | *recv_buf = newbuf; |
| 237 | *recv_buf_size -= (i+1); |
| 238 | *recv_buf_alloc -= (i+1); |
| 239 | |
| 240 | return 1; |
| 241 | } |
| 242 | |
| 243 | /* Receive a chunk from the fd */ |
| 244 | if(*recv_buf_alloc - *recv_buf_size < RECV_INCREMENT) { |
| 245 | *recv_buf_alloc += RECV_INCREMENT - (*recv_buf_alloc - *recv_buf_size); |
| 246 | *recv_buf = (char *) realloc(*recv_buf, *recv_buf_alloc); |
| 247 | } |
| 248 | |
| 249 | result = recv(fd, *recv_buf+*recv_buf_size, RECV_INCREMENT, 0); |
| 250 | if(result == -1) { |
| 251 | if(errno == ECONNRESET) { |
| 252 | *recv_buf_size = 0; |
| 253 | return 0; |
| 254 | } |
| 255 | else if(errno == EINTR) { |
| 256 | return -1; |
| 257 | } |
| 258 | else { |
| 259 | PERROR("recv"); |
| 260 | return -1; |
| 261 | } |
| 262 | } |
| 263 | if(result == 0) { |
| 264 | return 0; |
| 265 | } |
| 266 | *recv_buf_size += result; |
| 267 | |
| 268 | /* Go back to the beginning to check if there is a full message in the buffer */ |
| 269 | } |
| 270 | |
| 271 | DBG("received message \"%s\"", *recv_buf); |
| 272 | |
| 273 | return 1; |
| 274 | |
| 275 | } |
| 276 | |
| 277 | static int recv_message_conn(struct ustcomm_connection *conn, char **msg) |
| 278 | { |
| 279 | return recv_message_fd(conn->fd, &conn->recv_buf, &conn->recv_buf_size, &conn->recv_buf_alloc, msg); |
| 280 | } |
| 281 | |
| 282 | int ustcomm_send_reply(struct ustcomm_server *server, char *msg, struct ustcomm_source *src) |
| 283 | { |
| 284 | int result; |
| 285 | |
| 286 | result = send_message_fd(src->fd, msg); |
| 287 | if(result < 0) { |
| 288 | ERR("error in send_message_fd"); |
| 289 | return -1; |
| 290 | } |
| 291 | |
| 292 | return 0; |
| 293 | } |
| 294 | |
| 295 | /* Called after a fork. */ |
| 296 | |
| 297 | int ustcomm_close_all_connections(struct ustcomm_server *server) |
| 298 | { |
| 299 | struct ustcomm_connection *conn; |
| 300 | struct ustcomm_connection *deletable_conn = NULL; |
| 301 | |
| 302 | list_for_each_entry(conn, &server->connections, list) { |
| 303 | free(deletable_conn); |
| 304 | deletable_conn = conn; |
| 305 | ustcomm_close_app(conn); |
| 306 | list_del(&conn->list); |
| 307 | } |
| 308 | |
| 309 | return 0; |
| 310 | } |
| 311 | |
| 312 | /* @timeout: max blocking time in milliseconds, -1 means infinity |
| 313 | * |
| 314 | * returns 1 to indicate a message was received |
| 315 | * returns 0 to indicate no message was received |
| 316 | * returns -1 to indicate an error |
| 317 | */ |
| 318 | |
| 319 | int ustcomm_recv_message(struct ustcomm_server *server, char **msg, struct ustcomm_source *src, int timeout) |
| 320 | { |
| 321 | struct pollfd *fds; |
| 322 | struct ustcomm_connection **conn_table; |
| 323 | struct ustcomm_connection *conn; |
| 324 | int result; |
| 325 | int retval; |
| 326 | |
| 327 | for(;;) { |
| 328 | int idx = 0; |
| 329 | int n_fds = 1; |
| 330 | |
| 331 | list_for_each_entry(conn, &server->connections, list) { |
| 332 | n_fds++; |
| 333 | } |
| 334 | |
| 335 | fds = (struct pollfd *) malloc(n_fds * sizeof(struct pollfd)); |
| 336 | if(fds == NULL) { |
| 337 | ERR("malloc returned NULL"); |
| 338 | return -1; |
| 339 | } |
| 340 | |
| 341 | conn_table = (struct ustcomm_connection **) malloc(n_fds * sizeof(struct ustcomm_connection *)); |
| 342 | if(conn_table == NULL) { |
| 343 | ERR("malloc returned NULL"); |
| 344 | retval = -1; |
| 345 | goto free_fds_return; |
| 346 | } |
| 347 | |
| 348 | /* special idx 0 is for listening socket */ |
| 349 | fds[idx].fd = server->listen_fd; |
| 350 | fds[idx].events = POLLIN; |
| 351 | idx++; |
| 352 | |
| 353 | list_for_each_entry(conn, &server->connections, list) { |
| 354 | fds[idx].fd = conn->fd; |
| 355 | fds[idx].events = POLLIN; |
| 356 | conn_table[idx] = conn; |
| 357 | idx++; |
| 358 | } |
| 359 | |
| 360 | result = poll(fds, n_fds, timeout); |
| 361 | if(result == -1 && errno == EINTR) { |
| 362 | /* That's ok. ustd receives signals to notify it must shutdown. */ |
| 363 | retval = -1; |
| 364 | goto free_conn_table_return; |
| 365 | } |
| 366 | else if(result == -1) { |
| 367 | PERROR("poll"); |
| 368 | retval = -1; |
| 369 | goto free_conn_table_return; |
| 370 | } |
| 371 | else if(result == 0) { |
| 372 | retval = 0; |
| 373 | goto free_conn_table_return; |
| 374 | } |
| 375 | |
| 376 | if(fds[0].revents) { |
| 377 | struct ustcomm_connection *newconn; |
| 378 | int newfd; |
| 379 | |
| 380 | result = newfd = accept(server->listen_fd, NULL, NULL); |
| 381 | if(result == -1) { |
| 382 | PERROR("accept"); |
| 383 | retval = -1; |
| 384 | goto free_conn_table_return; |
| 385 | } |
| 386 | |
| 387 | newconn = (struct ustcomm_connection *) malloc(sizeof(struct ustcomm_connection)); |
| 388 | if(newconn == NULL) { |
| 389 | ERR("malloc returned NULL"); |
| 390 | return -1; |
| 391 | } |
| 392 | |
| 393 | ustcomm_init_connection(newconn); |
| 394 | newconn->fd = newfd; |
| 395 | |
| 396 | list_add(&newconn->list, &server->connections); |
| 397 | } |
| 398 | |
| 399 | for(idx=1; idx<n_fds; idx++) { |
| 400 | if(fds[idx].revents) { |
| 401 | retval = recv_message_conn(conn_table[idx], msg); |
| 402 | if(src) |
| 403 | src->fd = fds[idx].fd; |
| 404 | |
| 405 | if(retval == 0) { |
| 406 | /* connection finished */ |
| 407 | list_for_each_entry(conn, &server->connections, list) { |
| 408 | if(conn->fd == fds[idx].fd) { |
| 409 | ustcomm_close_app(conn); |
| 410 | list_del(&conn->list); |
| 411 | free(conn); |
| 412 | break; |
| 413 | } |
| 414 | } |
| 415 | } |
| 416 | else { |
| 417 | goto free_conn_table_return; |
| 418 | } |
| 419 | } |
| 420 | } |
| 421 | |
| 422 | free(fds); |
| 423 | free(conn_table); |
| 424 | } |
| 425 | |
| 426 | free_conn_table_return: |
| 427 | free(conn_table); |
| 428 | free_fds_return: |
| 429 | free(fds); |
| 430 | return retval; |
| 431 | } |
| 432 | |
| 433 | int ustcomm_ustd_recv_message(struct ustcomm_ustd *ustd, char **msg, struct ustcomm_source *src, int timeout) |
| 434 | { |
| 435 | return ustcomm_recv_message(&ustd->server, msg, src, timeout); |
| 436 | } |
| 437 | |
| 438 | int ustcomm_app_recv_message(struct ustcomm_app *app, char **msg, struct ustcomm_source *src, int timeout) |
| 439 | { |
| 440 | return ustcomm_recv_message(&app->server, msg, src, timeout); |
| 441 | } |
| 442 | |
| 443 | /* This removes src from the list of active connections of app. |
| 444 | */ |
| 445 | |
| 446 | int ustcomm_app_detach_client(struct ustcomm_app *app, struct ustcomm_source *src) |
| 447 | { |
| 448 | struct ustcomm_server *server = (struct ustcomm_server *)app; |
| 449 | struct ustcomm_connection *conn; |
| 450 | |
| 451 | list_for_each_entry(conn, &server->connections, list) { |
| 452 | if(conn->fd == src->fd) { |
| 453 | list_del(&conn->list); |
| 454 | goto found; |
| 455 | } |
| 456 | } |
| 457 | |
| 458 | return -1; |
| 459 | found: |
| 460 | return src->fd; |
| 461 | } |
| 462 | |
| 463 | static int init_named_socket(const char *name, char **path_out) |
| 464 | { |
| 465 | int result; |
| 466 | int fd; |
| 467 | |
| 468 | struct sockaddr_un addr; |
| 469 | |
| 470 | result = fd = socket(PF_UNIX, SOCK_STREAM, 0); |
| 471 | if(result == -1) { |
| 472 | PERROR("socket"); |
| 473 | return -1; |
| 474 | } |
| 475 | |
| 476 | addr.sun_family = AF_UNIX; |
| 477 | |
| 478 | strncpy(addr.sun_path, name, UNIX_PATH_MAX); |
| 479 | addr.sun_path[UNIX_PATH_MAX-1] = '\0'; |
| 480 | |
| 481 | result = access(name, F_OK); |
| 482 | if(result == 0) { |
| 483 | /* file exists */ |
| 484 | result = unlink(name); |
| 485 | if(result == -1) { |
| 486 | PERROR("unlink of socket file"); |
| 487 | goto close_sock; |
| 488 | } |
| 489 | DBG("socket already exists; overwriting"); |
| 490 | } |
| 491 | |
| 492 | result = bind(fd, (struct sockaddr *)&addr, sizeof(addr)); |
| 493 | if(result == -1) { |
| 494 | PERROR("bind"); |
| 495 | goto close_sock; |
| 496 | } |
| 497 | |
| 498 | result = listen(fd, 1); |
| 499 | if(result == -1) { |
| 500 | PERROR("listen"); |
| 501 | goto close_sock; |
| 502 | } |
| 503 | |
| 504 | if(path_out) { |
| 505 | *path_out = strdup(addr.sun_path); |
| 506 | } |
| 507 | |
| 508 | return fd; |
| 509 | |
| 510 | close_sock: |
| 511 | close(fd); |
| 512 | |
| 513 | return -1; |
| 514 | } |
| 515 | |
| 516 | /* |
| 517 | * Return value: |
| 518 | * 0: Success, but no reply because recv() returned 0 |
| 519 | * 1: Success |
| 520 | * -1: Error |
| 521 | * |
| 522 | * On error, the error message is printed, except on |
| 523 | * ECONNRESET, which is normal when the application dies. |
| 524 | */ |
| 525 | |
| 526 | int ustcomm_send_request(struct ustcomm_connection *conn, const char *req, char **reply) |
| 527 | { |
| 528 | int result; |
| 529 | |
| 530 | /* Send including the final \0 */ |
| 531 | result = send_message_fd(conn->fd, req); |
| 532 | if(result != 1) |
| 533 | return result; |
| 534 | |
| 535 | if(!reply) |
| 536 | return 1; |
| 537 | |
| 538 | result = recv_message_conn(conn, reply); |
| 539 | if(result == -1) { |
| 540 | return -1; |
| 541 | } |
| 542 | else if(result == 0) { |
| 543 | return 0; |
| 544 | } |
| 545 | |
| 546 | return 1; |
| 547 | } |
| 548 | |
| 549 | /* Return value: |
| 550 | * 0: success |
| 551 | * -1: error |
| 552 | */ |
| 553 | |
| 554 | int ustcomm_connect_path(const char *path, struct ustcomm_connection *conn, pid_t signalpid) |
| 555 | { |
| 556 | int fd; |
| 557 | int result; |
| 558 | struct sockaddr_un addr; |
| 559 | |
| 560 | ustcomm_init_connection(conn); |
| 561 | |
| 562 | result = fd = socket(PF_UNIX, SOCK_STREAM, 0); |
| 563 | if(result == -1) { |
| 564 | PERROR("socket"); |
| 565 | return -1; |
| 566 | } |
| 567 | |
| 568 | addr.sun_family = AF_UNIX; |
| 569 | |
| 570 | result = snprintf(addr.sun_path, UNIX_PATH_MAX, "%s", path); |
| 571 | if(result >= UNIX_PATH_MAX) { |
| 572 | ERR("string overflow allocating socket name"); |
| 573 | return -1; |
| 574 | } |
| 575 | |
| 576 | if(signalpid >= 0) { |
| 577 | result = signal_process(signalpid); |
| 578 | if(result == -1) { |
| 579 | ERR("could not signal process"); |
| 580 | return -1; |
| 581 | } |
| 582 | } |
| 583 | |
| 584 | result = connect(fd, (struct sockaddr *)&addr, sizeof(addr)); |
| 585 | if(result == -1) { |
| 586 | PERROR("connect (path=%s)", path); |
| 587 | return -1; |
| 588 | } |
| 589 | |
| 590 | conn->fd = fd; |
| 591 | |
| 592 | return 0; |
| 593 | } |
| 594 | |
| 595 | int ustcomm_disconnect(struct ustcomm_connection *conn) |
| 596 | { |
| 597 | return close(conn->fd); |
| 598 | } |
| 599 | |
| 600 | /* Open a connection to a traceable app. |
| 601 | * |
| 602 | * Return value: |
| 603 | * 0: success |
| 604 | * -1: error |
| 605 | */ |
| 606 | |
| 607 | int ustcomm_connect_app(pid_t pid, struct ustcomm_connection *conn) |
| 608 | { |
| 609 | int result; |
| 610 | char path[UNIX_PATH_MAX]; |
| 611 | |
| 612 | |
| 613 | result = snprintf(path, UNIX_PATH_MAX, "%s/%d", SOCK_DIR, pid); |
| 614 | if(result >= UNIX_PATH_MAX) { |
| 615 | ERR("string overflow allocating socket name"); |
| 616 | return -1; |
| 617 | } |
| 618 | |
| 619 | return ustcomm_connect_path(path, conn, pid); |
| 620 | } |
| 621 | |
| 622 | /* Close a connection to a traceable app. It frees the |
| 623 | * resources. It however does not free the |
| 624 | * ustcomm_connection itself. |
| 625 | */ |
| 626 | |
| 627 | int ustcomm_close_app(struct ustcomm_connection *conn) |
| 628 | { |
| 629 | close(conn->fd); |
| 630 | free(conn->recv_buf); |
| 631 | |
| 632 | return 0; |
| 633 | } |
| 634 | |
| 635 | static int ensure_dir_exists(const char *dir) |
| 636 | { |
| 637 | struct stat st; |
| 638 | int result; |
| 639 | |
| 640 | if(!strcmp(dir, "")) |
| 641 | return -1; |
| 642 | |
| 643 | result = stat(dir, &st); |
| 644 | if(result == -1 && errno != ENOENT) { |
| 645 | return -1; |
| 646 | } |
| 647 | else if(result == -1) { |
| 648 | /* ENOENT */ |
| 649 | int result; |
| 650 | |
| 651 | /* mkdir mode to 0777 */ |
| 652 | result = mkdir_p(dir, S_IRWXU | S_IRWXG | S_IRWXO); |
| 653 | if(result != 0) { |
| 654 | ERR("executing in recursive creation of directory %s", dir); |
| 655 | return -1; |
| 656 | } |
| 657 | } |
| 658 | |
| 659 | return 0; |
| 660 | } |
| 661 | |
| 662 | /* Called by an application to initialize its server so daemons can |
| 663 | * connect to it. |
| 664 | */ |
| 665 | |
| 666 | int ustcomm_init_app(pid_t pid, struct ustcomm_app *handle) |
| 667 | { |
| 668 | int result; |
| 669 | char *name; |
| 670 | |
| 671 | result = asprintf(&name, "%s/%d", SOCK_DIR, (int)pid); |
| 672 | if(result >= UNIX_PATH_MAX) { |
| 673 | ERR("string overflow allocating socket name"); |
| 674 | return -1; |
| 675 | } |
| 676 | |
| 677 | result = ensure_dir_exists(SOCK_DIR); |
| 678 | if(result == -1) { |
| 679 | ERR("Unable to create socket directory %s", SOCK_DIR); |
| 680 | return -1; |
| 681 | } |
| 682 | |
| 683 | handle->server.listen_fd = init_named_socket(name, &(handle->server.socketpath)); |
| 684 | if(handle->server.listen_fd < 0) { |
| 685 | ERR("Error initializing named socket (%s). Check that directory exists and that it is writable.", name); |
| 686 | goto free_name; |
| 687 | } |
| 688 | free(name); |
| 689 | |
| 690 | INIT_LIST_HEAD(&handle->server.connections); |
| 691 | |
| 692 | return 0; |
| 693 | |
| 694 | free_name: |
| 695 | free(name); |
| 696 | return -1; |
| 697 | } |
| 698 | |
| 699 | /* Used by the daemon to initialize its server so applications |
| 700 | * can connect to it. |
| 701 | */ |
| 702 | |
| 703 | int ustcomm_init_ustd(struct ustcomm_ustd *handle, const char *sock_path) |
| 704 | { |
| 705 | char *name; |
| 706 | int retval = 0; |
| 707 | |
| 708 | if(sock_path) { |
| 709 | asprintf(&name, "%s", sock_path); |
| 710 | } |
| 711 | else { |
| 712 | int result; |
| 713 | |
| 714 | /* Only check if socket dir exists if we are using the default directory */ |
| 715 | result = ensure_dir_exists(SOCK_DIR); |
| 716 | if(result == -1) { |
| 717 | ERR("Unable to create socket directory %s", SOCK_DIR); |
| 718 | return -1; |
| 719 | } |
| 720 | |
| 721 | asprintf(&name, "%s/%s", SOCK_DIR, "ustd"); |
| 722 | } |
| 723 | |
| 724 | handle->server.listen_fd = init_named_socket(name, &handle->server.socketpath); |
| 725 | if(handle->server.listen_fd < 0) { |
| 726 | ERR("error initializing named socket at %s", name); |
| 727 | retval = -1; |
| 728 | goto free_name; |
| 729 | } |
| 730 | |
| 731 | INIT_LIST_HEAD(&handle->server.connections); |
| 732 | |
| 733 | free_name: |
| 734 | free(name); |
| 735 | |
| 736 | return retval; |
| 737 | } |
| 738 | |
| 739 | static void ustcomm_fini_server(struct ustcomm_server *server, int keep_socket_file) |
| 740 | { |
| 741 | int result; |
| 742 | struct stat st; |
| 743 | |
| 744 | if(!keep_socket_file) { |
| 745 | /* Destroy socket */ |
| 746 | result = stat(server->socketpath, &st); |
| 747 | if(result == -1) { |
| 748 | PERROR("stat (%s)", server->socketpath); |
| 749 | return; |
| 750 | } |
| 751 | |
| 752 | /* Paranoid check before deleting. */ |
| 753 | result = S_ISSOCK(st.st_mode); |
| 754 | if(!result) { |
| 755 | ERR("The socket we are about to delete is not a socket."); |
| 756 | return; |
| 757 | } |
| 758 | |
| 759 | result = unlink(server->socketpath); |
| 760 | if(result == -1) { |
| 761 | PERROR("unlink"); |
| 762 | } |
| 763 | } |
| 764 | |
| 765 | free(server->socketpath); |
| 766 | |
| 767 | result = close(server->listen_fd); |
| 768 | if(result == -1) { |
| 769 | PERROR("close"); |
| 770 | return; |
| 771 | } |
| 772 | } |
| 773 | |
| 774 | /* Free a traceable application server */ |
| 775 | |
| 776 | void ustcomm_fini_app(struct ustcomm_app *handle, int keep_socket_file) |
| 777 | { |
| 778 | ustcomm_fini_server(&handle->server, keep_socket_file); |
| 779 | } |
| 780 | |
| 781 | /* Free a ustd server */ |
| 782 | |
| 783 | void ustcomm_fini_ustd(struct ustcomm_ustd *handle) |
| 784 | { |
| 785 | ustcomm_fini_server(&handle->server, 0); |
| 786 | } |
| 787 | |
| 788 | static const char *find_tok(const char *str) |
| 789 | { |
| 790 | while(*str == ' ') { |
| 791 | str++; |
| 792 | |
| 793 | if(*str == 0) |
| 794 | return NULL; |
| 795 | } |
| 796 | |
| 797 | return str; |
| 798 | } |
| 799 | |
| 800 | static const char *find_sep(const char *str) |
| 801 | { |
| 802 | while(*str != ' ') { |
| 803 | str++; |
| 804 | |
| 805 | if(*str == 0) |
| 806 | break; |
| 807 | } |
| 808 | |
| 809 | return str; |
| 810 | } |
| 811 | |
| 812 | int nth_token_is(const char *str, const char *token, int tok_no) |
| 813 | { |
| 814 | int i; |
| 815 | const char *start; |
| 816 | const char *end; |
| 817 | |
| 818 | for(i=0; i<=tok_no; i++) { |
| 819 | str = find_tok(str); |
| 820 | if(str == NULL) |
| 821 | return -1; |
| 822 | |
| 823 | start = str; |
| 824 | |
| 825 | str = find_sep(str); |
| 826 | if(str == NULL) |
| 827 | return -1; |
| 828 | |
| 829 | end = str; |
| 830 | } |
| 831 | |
| 832 | if(end-start != strlen(token)) |
| 833 | return 0; |
| 834 | |
| 835 | if(strncmp(start, token, end-start)) |
| 836 | return 0; |
| 837 | |
| 838 | return 1; |
| 839 | } |
| 840 | |
| 841 | char *nth_token(const char *str, int tok_no) |
| 842 | { |
| 843 | static char *retval = NULL; |
| 844 | int i; |
| 845 | const char *start; |
| 846 | const char *end; |
| 847 | |
| 848 | for(i=0; i<=tok_no; i++) { |
| 849 | str = find_tok(str); |
| 850 | if(str == NULL) |
| 851 | return NULL; |
| 852 | |
| 853 | start = str; |
| 854 | |
| 855 | str = find_sep(str); |
| 856 | if(str == NULL) |
| 857 | return NULL; |
| 858 | |
| 859 | end = str; |
| 860 | } |
| 861 | |
| 862 | if(retval) { |
| 863 | free(retval); |
| 864 | retval = NULL; |
| 865 | } |
| 866 | |
| 867 | asprintf(&retval, "%.*s", (int)(end-start), start); |
| 868 | |
| 869 | return retval; |
| 870 | } |
| 871 | |
| 872 | /* Callback from multipoll. |
| 873 | * Receive a new connection on the listening socket. |
| 874 | */ |
| 875 | |
| 876 | static int process_mp_incoming_conn(void *priv, int fd, short events) |
| 877 | { |
| 878 | struct ustcomm_connection *newconn; |
| 879 | struct ustcomm_server *server = (struct ustcomm_server *) priv; |
| 880 | int newfd; |
| 881 | int result; |
| 882 | |
| 883 | result = newfd = accept(server->listen_fd, NULL, NULL); |
| 884 | if(result == -1) { |
| 885 | PERROR("accept"); |
| 886 | return -1; |
| 887 | } |
| 888 | |
| 889 | newconn = (struct ustcomm_connection *) malloc(sizeof(struct ustcomm_connection)); |
| 890 | if(newconn == NULL) { |
| 891 | ERR("malloc returned NULL"); |
| 892 | return -1; |
| 893 | } |
| 894 | |
| 895 | ustcomm_init_connection(newconn); |
| 896 | newconn->fd = newfd; |
| 897 | |
| 898 | list_add(&newconn->list, &server->connections); |
| 899 | |
| 900 | return 0; |
| 901 | } |
| 902 | |
| 903 | /* Callback from multipoll. |
| 904 | * Receive a message on an existing connection. |
| 905 | */ |
| 906 | |
| 907 | static int process_mp_conn_msg(void *priv, int fd, short revents) |
| 908 | { |
| 909 | struct ustcomm_multipoll_conn_info *mpinfo = (struct ustcomm_multipoll_conn_info *) priv; |
| 910 | int result; |
| 911 | char *msg; |
| 912 | struct ustcomm_source src; |
| 913 | |
| 914 | if(revents) { |
| 915 | src.fd = fd; |
| 916 | |
| 917 | result = recv_message_conn(mpinfo->conn, &msg); |
| 918 | if(result == -1) { |
| 919 | ERR("error in recv_message_conn"); |
| 920 | } |
| 921 | |
| 922 | else if(result == 0) { |
| 923 | /* connection finished */ |
| 924 | ustcomm_close_app(mpinfo->conn); |
| 925 | list_del(&mpinfo->conn->list); |
| 926 | free(mpinfo->conn); |
| 927 | } |
| 928 | else { |
| 929 | mpinfo->cb(msg, &src); |
| 930 | free(msg); |
| 931 | } |
| 932 | } |
| 933 | |
| 934 | return 0; |
| 935 | } |
| 936 | |
| 937 | int free_ustcomm_client_poll(void *data) |
| 938 | { |
| 939 | free(data); |
| 940 | return 0; |
| 941 | } |
| 942 | |
| 943 | void ustcomm_mp_add_app_clients(struct mpentries *ent, struct ustcomm_app *app, int (*cb)(char *recvbuf, struct ustcomm_source *src)) |
| 944 | { |
| 945 | struct ustcomm_connection *conn; |
| 946 | |
| 947 | /* add listener socket */ |
| 948 | multipoll_add(ent, app->server.listen_fd, POLLIN, process_mp_incoming_conn, &app->server, NULL); |
| 949 | |
| 950 | list_for_each_entry(conn, &app->server.connections, list) { |
| 951 | struct ustcomm_multipoll_conn_info *mpinfo = (struct ustcomm_multipoll_conn_info *) malloc(sizeof(struct ustcomm_multipoll_conn_info)); |
| 952 | mpinfo->conn = conn; |
| 953 | mpinfo->cb = cb; |
| 954 | multipoll_add(ent, conn->fd, POLLIN, process_mp_conn_msg, mpinfo, free_ustcomm_client_poll); |
| 955 | } |
| 956 | } |