1 /* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp. 2 * 3 * Permission is hereby granted, free of charge, to any person obtaining a 4 * copy of this software and associated documentation files (the "Software"), 5 * to deal in the Software without restriction, including without limitation 6 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 7 * and/or sell copies of the Software, and to permit persons to whom the 8 * Software is furnished to do so, subject to the following conditions: 9 * 10 * The above copyright notice and this permission notice shall be included in 11 * all copies or substantial portions of the Software. 12 * 13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 17 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 18 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 19 * 20 * Except as contained in this notice, the names of the authors or their 21 * institutions shall not be used in advertising or otherwise to promote the 22 * sale, use or other dealings in this Software without prior written 23 * authorization from the authors. 24 */ 25 26 /* Stuff that reads stuff from the server. */ 27 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <assert.h> 33 #include <string.h> 34 #include <stdlib.h> 35 #include <stdio.h> 36 #include <errno.h> 37 38 #if USE_POLL 39 #include <poll.h> 40 #endif 41 #ifndef _WIN32 42 #include <unistd.h> 43 #include <sys/select.h> 44 #include <sys/socket.h> 45 #endif 46 47 #ifdef _WIN32 48 #include "xcb_windefs.h" 49 #endif /* _WIN32 */ 50 51 #include "xcb.h" 52 #include "xcbext.h" 53 #include "xcbint.h" 54 55 #define XCB_ERROR 0 56 #define XCB_REPLY 1 57 #define XCB_XGE_EVENT 35 58 59 struct event_list { 60 xcb_generic_event_t *event; 61 struct event_list *next; 62 }; 63 64 struct xcb_special_event { 65 66 struct xcb_special_event *next; 67 68 /* Match XGE events for the specific extension and event ID (the 69 * first 32 bit word after evtype) 70 */ 71 uint8_t extension; 72 uint32_t eid; 73 uint32_t *stamp; 74 75 struct event_list *events; 76 struct event_list **events_tail; 77 78 pthread_cond_t special_event_cond; 79 }; 80 81 struct reply_list { 82 void *reply; 83 struct reply_list *next; 84 }; 85 86 typedef struct pending_reply { 87 uint64_t first_request; 88 uint64_t last_request; 89 enum workarounds workaround; 90 int flags; 91 struct pending_reply *next; 92 } pending_reply; 93 94 typedef struct reader_list { 95 uint64_t request; 96 pthread_cond_t *data; 97 struct reader_list *next; 98 } reader_list; 99 100 typedef struct special_list { 101 xcb_special_event_t *se; 102 struct special_list *next; 103 } special_list; 104 105 static void remove_finished_readers(reader_list **prev_reader, uint64_t completed) 106 { 107 while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, completed)) 108 { 109 /* If you don't have what you're looking for now, you never 110 * will. Wake up and leave me alone. */ 111 pthread_cond_signal((*prev_reader)->data); 112 *prev_reader = (*prev_reader)->next; 113 } 114 } 115 116 #if HAVE_SENDMSG 117 static int read_fds(xcb_connection_t *c, int *fds, int nfd) 118 { 119 int *ifds = &c->in.in_fd.fd[c->in.in_fd.ifd]; 120 int infd = c->in.in_fd.nfd - c->in.in_fd.ifd; 121 122 if (nfd > infd) 123 return 0; 124 memcpy(fds, ifds, nfd * sizeof (int)); 125 c->in.in_fd.ifd += nfd; 126 return 1; 127 } 128 #endif 129 130 typedef struct xcb_ge_special_event_t { 131 uint8_t response_type; /**< */ 132 uint8_t extension; /**< */ 133 uint16_t sequence; /**< */ 134 uint32_t length; /**< */ 135 uint16_t evtype; /**< */ 136 uint8_t pad0[2]; /**< */ 137 uint32_t eid; /**< */ 138 uint8_t pad1[16]; /**< */ 139 } xcb_ge_special_event_t; 140 141 static int event_special(xcb_connection_t *c, 142 struct event_list *event) 143 { 144 struct xcb_special_event *special_event; 145 struct xcb_ge_special_event_t *ges = (void *) event->event; 146 147 /* Special events are always XGE events */ 148 if ((ges->response_type & 0x7f) != XCB_XGE_EVENT) 149 return 0; 150 151 for (special_event = c->in.special_events; 152 special_event; 153 special_event = special_event->next) 154 { 155 if (ges->extension == special_event->extension && 156 ges->eid == special_event->eid) 157 { 158 *special_event->events_tail = event; 159 special_event->events_tail = &event->next; 160 if (special_event->stamp) 161 ++(*special_event->stamp); 162 pthread_cond_signal(&special_event->special_event_cond); 163 return 1; 164 } 165 } 166 167 return 0; 168 } 169 170 static int read_packet(xcb_connection_t *c) 171 { 172 xcb_generic_reply_t genrep; 173 uint64_t length = 32; 174 uint64_t eventlength = 0; /* length after first 32 bytes for GenericEvents */ 175 int nfd = 0; /* Number of file descriptors attached to the reply */ 176 uint64_t bufsize; 177 void *buf; 178 pending_reply *pend = 0; 179 struct event_list *event; 180 181 /* Wait for there to be enough data for us to read a whole packet */ 182 if(c->in.queue_len < length) 183 return 0; 184 185 /* Get the response type, length, and sequence number. */ 186 memcpy(&genrep, c->in.queue, sizeof(genrep)); 187 188 /* Compute 32-bit sequence number of this packet. */ 189 if((genrep.response_type & 0x7f) != XCB_KEYMAP_NOTIFY) 190 { 191 uint64_t lastread = c->in.request_read; 192 c->in.request_read = (lastread & UINT64_C(0xffffffffffff0000)) | genrep.sequence; 193 if(XCB_SEQUENCE_COMPARE(c->in.request_read, <, lastread)) 194 c->in.request_read += 0x10000; 195 if(XCB_SEQUENCE_COMPARE(c->in.request_read, >, c->in.request_expected)) 196 c->in.request_expected = c->in.request_read; 197 198 if(c->in.request_read != lastread) 199 { 200 if(c->in.current_reply) 201 { 202 _xcb_map_put(c->in.replies, lastread, c->in.current_reply); 203 c->in.current_reply = 0; 204 c->in.current_reply_tail = &c->in.current_reply; 205 } 206 c->in.request_completed = c->in.request_read - 1; 207 } 208 209 while(c->in.pending_replies && 210 c->in.pending_replies->workaround != WORKAROUND_EXTERNAL_SOCKET_OWNER && 211 XCB_SEQUENCE_COMPARE (c->in.pending_replies->last_request, <=, c->in.request_completed)) 212 { 213 pending_reply *oldpend = c->in.pending_replies; 214 c->in.pending_replies = oldpend->next; 215 if(!oldpend->next) 216 c->in.pending_replies_tail = &c->in.pending_replies; 217 free(oldpend); 218 } 219 220 if(genrep.response_type == XCB_ERROR) 221 c->in.request_completed = c->in.request_read; 222 223 remove_finished_readers(&c->in.readers, c->in.request_completed); 224 } 225 226 if(genrep.response_type == XCB_ERROR || genrep.response_type == XCB_REPLY) 227 { 228 pend = c->in.pending_replies; 229 if(pend && 230 !(XCB_SEQUENCE_COMPARE(pend->first_request, <=, c->in.request_read) && 231 (pend->workaround == WORKAROUND_EXTERNAL_SOCKET_OWNER || 232 XCB_SEQUENCE_COMPARE(c->in.request_read, <=, pend->last_request)))) 233 pend = 0; 234 } 235 236 /* For reply packets, check that the entire packet is available. */ 237 if(genrep.response_type == XCB_REPLY) 238 { 239 if(pend && pend->workaround == WORKAROUND_GLX_GET_FB_CONFIGS_BUG) 240 { 241 uint32_t *p = (uint32_t *) c->in.queue; 242 uint64_t new_length = ((uint64_t)p[2]) * ((uint64_t)p[3]); 243 if(new_length >= (UINT32_MAX / UINT32_C(16))) 244 { 245 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 246 return 0; 247 } 248 genrep.length = (uint32_t)(new_length * UINT64_C(2)); 249 } 250 length += genrep.length * UINT64_C(4); 251 252 /* XXX a bit of a hack -- we "know" that all FD replys place 253 * the number of fds in the pad0 byte */ 254 if (pend && pend->flags & XCB_REQUEST_REPLY_FDS) 255 nfd = genrep.pad0; 256 } 257 258 /* XGE events may have sizes > 32 */ 259 if ((genrep.response_type & 0x7f) == XCB_XGE_EVENT) 260 eventlength = genrep.length * UINT64_C(4); 261 262 bufsize = length + eventlength + nfd * sizeof(int) + 263 (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t)); 264 if (bufsize < INT32_MAX) 265 buf = malloc((size_t) bufsize); 266 else 267 buf = NULL; 268 if(!buf) 269 { 270 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 271 return 0; 272 } 273 274 if(_xcb_in_read_block(c, buf, length) <= 0) 275 { 276 free(buf); 277 return 0; 278 } 279 280 /* pull in XGE event data if available, append after event struct */ 281 if (eventlength) 282 { 283 if(_xcb_in_read_block(c, &((xcb_generic_event_t*)buf)[1], eventlength) <= 0) 284 { 285 free(buf); 286 return 0; 287 } 288 } 289 290 #if HAVE_SENDMSG 291 if (nfd) 292 { 293 if (!read_fds(c, (int *) &((char *) buf)[length], nfd)) 294 { 295 free(buf); 296 return 0; 297 } 298 } 299 #endif 300 301 if(pend && (pend->flags & XCB_REQUEST_DISCARD_REPLY)) 302 { 303 free(buf); 304 return 1; 305 } 306 307 if(genrep.response_type != XCB_REPLY) 308 ((xcb_generic_event_t *) buf)->full_sequence = c->in.request_read; 309 310 /* reply, or checked error */ 311 if( genrep.response_type == XCB_REPLY || 312 (genrep.response_type == XCB_ERROR && pend && (pend->flags & XCB_REQUEST_CHECKED))) 313 { 314 struct reply_list *cur = malloc(sizeof(struct reply_list)); 315 if(!cur) 316 { 317 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 318 free(buf); 319 return 0; 320 } 321 cur->reply = buf; 322 cur->next = 0; 323 *c->in.current_reply_tail = cur; 324 c->in.current_reply_tail = &cur->next; 325 if(c->in.readers && c->in.readers->request == c->in.request_read) 326 pthread_cond_signal(c->in.readers->data); 327 return 1; 328 } 329 330 /* event, or unchecked error */ 331 event = malloc(sizeof(struct event_list)); 332 if(!event) 333 { 334 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 335 free(buf); 336 return 0; 337 } 338 event->event = buf; 339 event->next = 0; 340 341 if (!event_special(c, event)) { 342 *c->in.events_tail = event; 343 c->in.events_tail = &event->next; 344 pthread_cond_signal(&c->in.event_cond); 345 } 346 return 1; /* I have something for you... */ 347 } 348 349 static xcb_generic_event_t *get_event(xcb_connection_t *c) 350 { 351 struct event_list *cur = c->in.events; 352 xcb_generic_event_t *ret; 353 if(!c->in.events) 354 return 0; 355 ret = cur->event; 356 c->in.events = cur->next; 357 if(!cur->next) 358 c->in.events_tail = &c->in.events; 359 free(cur); 360 return ret; 361 } 362 363 static void free_reply_list(struct reply_list *head) 364 { 365 while(head) 366 { 367 struct reply_list *cur = head; 368 head = cur->next; 369 free(cur->reply); 370 free(cur); 371 } 372 } 373 374 static int read_block(const int fd, void *buf, const intptr_t len) 375 { 376 int done = 0; 377 while(done < len) 378 { 379 int ret = recv(fd, ((char *) buf) + done, len - done, 0); 380 if(ret > 0) 381 done += ret; 382 #ifndef _WIN32 383 if(ret < 0 && errno == EAGAIN) 384 #else 385 if(ret == SOCKET_ERROR && WSAGetLastError() == WSAEWOULDBLOCK) 386 #endif /* !_Win32 */ 387 { 388 #if USE_POLL 389 struct pollfd pfd; 390 pfd.fd = fd; 391 pfd.events = POLLIN; 392 pfd.revents = 0; 393 do { 394 ret = poll(&pfd, 1, -1); 395 } while (ret == -1 && errno == EINTR); 396 #else 397 fd_set fds; 398 FD_ZERO(&fds); 399 FD_SET(fd, &fds); 400 401 /* Initializing errno here makes sure that for Win32 this loop will execute only once */ 402 errno = 0; 403 do { 404 ret = select(fd + 1, &fds, 0, 0, 0); 405 } while (ret == -1 && errno == EINTR); 406 #endif /* USE_POLL */ 407 } 408 if(ret <= 0) 409 return ret; 410 } 411 return len; 412 } 413 414 static int poll_for_reply(xcb_connection_t *c, uint64_t request, void **reply, xcb_generic_error_t **error) 415 { 416 struct reply_list *head; 417 418 /* If an error occurred when issuing the request, fail immediately. */ 419 if(!request) 420 head = 0; 421 /* We've read requests past the one we want, so if it has replies we have 422 * them all and they're in the replies map. */ 423 else if(XCB_SEQUENCE_COMPARE(request, <, c->in.request_read)) 424 { 425 head = _xcb_map_remove(c->in.replies, request); 426 if(head && head->next) 427 _xcb_map_put(c->in.replies, request, head->next); 428 } 429 /* We're currently processing the responses to the request we want, and we 430 * have a reply ready to return. So just return it without blocking. */ 431 else if(request == c->in.request_read && c->in.current_reply) 432 { 433 head = c->in.current_reply; 434 c->in.current_reply = head->next; 435 if(!head->next) 436 c->in.current_reply_tail = &c->in.current_reply; 437 } 438 /* We know this request can't have any more replies, and we've already 439 * established it doesn't have a reply now. Don't bother blocking. */ 440 else if(request == c->in.request_completed) 441 head = 0; 442 /* We may have more replies on the way for this request: block until we're 443 * sure. */ 444 else 445 return 0; 446 447 if(error) 448 *error = 0; 449 *reply = 0; 450 451 if(head) 452 { 453 if(((xcb_generic_reply_t *) head->reply)->response_type == XCB_ERROR) 454 { 455 if(error) 456 *error = head->reply; 457 else 458 free(head->reply); 459 } 460 else 461 *reply = head->reply; 462 463 free(head); 464 } 465 466 return 1; 467 } 468 469 static void insert_reader(reader_list **prev_reader, reader_list *reader, uint64_t request, pthread_cond_t *cond) 470 { 471 while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, request)) 472 prev_reader = &(*prev_reader)->next; 473 reader->request = request; 474 reader->data = cond; 475 reader->next = *prev_reader; 476 *prev_reader = reader; 477 } 478 479 static void remove_reader(reader_list **prev_reader, reader_list *reader) 480 { 481 while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, reader->request)) 482 if(*prev_reader == reader) 483 { 484 *prev_reader = (*prev_reader)->next; 485 break; 486 } 487 } 488 489 static void insert_special(special_list **prev_special, special_list *special, xcb_special_event_t *se) 490 { 491 special->se = se; 492 special->next = *prev_special; 493 *prev_special = special; 494 } 495 496 static void remove_special(special_list **prev_special, special_list *special) 497 { 498 while(*prev_special) 499 { 500 if(*prev_special == special) 501 { 502 *prev_special = (*prev_special)->next; 503 break; 504 } 505 prev_special = &(*prev_special)->next; 506 } 507 } 508 509 static void *wait_for_reply(xcb_connection_t *c, uint64_t request, xcb_generic_error_t **e) 510 { 511 void *ret = 0; 512 513 /* If this request has not been written yet, write it. */ 514 if(c->out.return_socket || _xcb_out_flush_to(c, request)) 515 { 516 pthread_cond_t cond = PTHREAD_COND_INITIALIZER; 517 reader_list reader; 518 519 insert_reader(&c->in.readers, &reader, request, &cond); 520 521 while(!poll_for_reply(c, request, &ret, e)) 522 if(!_xcb_conn_wait(c, &cond, 0, 0)) 523 break; 524 525 remove_reader(&c->in.readers, &reader); 526 pthread_cond_destroy(&cond); 527 } 528 529 _xcb_in_wake_up_next_reader(c); 530 return ret; 531 } 532 533 static uint64_t widen(xcb_connection_t *c, unsigned int request) 534 { 535 uint64_t widened_request = (c->out.request & UINT64_C(0xffffffff00000000)) | request; 536 if(widened_request > c->out.request) 537 widened_request -= UINT64_C(1) << 32; 538 return widened_request; 539 } 540 541 /* Public interface */ 542 543 void *xcb_wait_for_reply(xcb_connection_t *c, unsigned int request, xcb_generic_error_t **e) 544 { 545 void *ret; 546 if(e) 547 *e = 0; 548 if(c->has_error) 549 return 0; 550 551 pthread_mutex_lock(&c->iolock); 552 ret = wait_for_reply(c, widen(c, request), e); 553 pthread_mutex_unlock(&c->iolock); 554 return ret; 555 } 556 557 void *xcb_wait_for_reply64(xcb_connection_t *c, uint64_t request, xcb_generic_error_t **e) 558 { 559 void *ret; 560 if(e) 561 *e = 0; 562 if(c->has_error) 563 return 0; 564 565 pthread_mutex_lock(&c->iolock); 566 ret = wait_for_reply(c, request, e); 567 pthread_mutex_unlock(&c->iolock); 568 return ret; 569 } 570 571 int *xcb_get_reply_fds(xcb_connection_t *c, void *reply, size_t reply_size) 572 { 573 return (int *) (&((char *) reply)[reply_size]); 574 } 575 576 static void insert_pending_discard(xcb_connection_t *c, pending_reply **prev_next, uint64_t seq) 577 { 578 pending_reply *pend; 579 pend = malloc(sizeof(*pend)); 580 if(!pend) 581 { 582 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 583 return; 584 } 585 586 pend->first_request = seq; 587 pend->last_request = seq; 588 pend->workaround = 0; 589 pend->flags = XCB_REQUEST_DISCARD_REPLY; 590 pend->next = *prev_next; 591 *prev_next = pend; 592 593 if(!pend->next) 594 c->in.pending_replies_tail = &pend->next; 595 } 596 597 static void discard_reply(xcb_connection_t *c, uint64_t request) 598 { 599 void *reply; 600 pending_reply **prev_pend; 601 602 /* Free any replies or errors that we've already read. Stop if 603 * xcb_wait_for_reply would block or we've run out of replies. */ 604 while(poll_for_reply(c, request, &reply, 0) && reply) 605 free(reply); 606 607 /* If we've proven there are no more responses coming, we're done. */ 608 if(XCB_SEQUENCE_COMPARE(request, <=, c->in.request_completed)) 609 return; 610 611 /* Walk the list of pending requests. Mark the first match for deletion. */ 612 for(prev_pend = &c->in.pending_replies; *prev_pend; prev_pend = &(*prev_pend)->next) 613 { 614 if(XCB_SEQUENCE_COMPARE((*prev_pend)->first_request, >, request)) 615 break; 616 617 if((*prev_pend)->first_request == request) 618 { 619 /* Pending reply found. Mark for discard: */ 620 (*prev_pend)->flags |= XCB_REQUEST_DISCARD_REPLY; 621 return; 622 } 623 } 624 625 /* Pending reply not found (likely due to _unchecked request). Create one: */ 626 insert_pending_discard(c, prev_pend, request); 627 } 628 629 void xcb_discard_reply(xcb_connection_t *c, unsigned int sequence) 630 { 631 if(c->has_error) 632 return; 633 634 /* If an error occurred when issuing the request, fail immediately. */ 635 if(!sequence) 636 return; 637 638 pthread_mutex_lock(&c->iolock); 639 discard_reply(c, widen(c, sequence)); 640 pthread_mutex_unlock(&c->iolock); 641 } 642 643 void xcb_discard_reply64(xcb_connection_t *c, uint64_t sequence) 644 { 645 if(c->has_error) 646 return; 647 648 /* If an error occurred when issuing the request, fail immediately. */ 649 if(!sequence) 650 return; 651 652 pthread_mutex_lock(&c->iolock); 653 discard_reply(c, sequence); 654 pthread_mutex_unlock(&c->iolock); 655 } 656 657 int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error) 658 { 659 int ret; 660 if(c->has_error) 661 { 662 *reply = 0; 663 if(error) 664 *error = 0; 665 return 1; /* would not block */ 666 } 667 assert(reply != 0); 668 pthread_mutex_lock(&c->iolock); 669 ret = poll_for_reply(c, widen(c, request), reply, error); 670 if(!ret && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ 671 ret = poll_for_reply(c, widen(c, request), reply, error); 672 pthread_mutex_unlock(&c->iolock); 673 return ret; 674 } 675 676 int xcb_poll_for_reply64(xcb_connection_t *c, uint64_t request, void **reply, xcb_generic_error_t **error) 677 { 678 int ret; 679 if(c->has_error) 680 { 681 *reply = 0; 682 if(error) 683 *error = 0; 684 return 1; /* would not block */ 685 } 686 assert(reply != 0); 687 pthread_mutex_lock(&c->iolock); 688 ret = poll_for_reply(c, request, reply, error); 689 if(!ret && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ 690 ret = poll_for_reply(c, request, reply, error); 691 pthread_mutex_unlock(&c->iolock); 692 return ret; 693 } 694 695 xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c) 696 { 697 xcb_generic_event_t *ret; 698 if(c->has_error) 699 return 0; 700 pthread_mutex_lock(&c->iolock); 701 /* get_event returns 0 on empty list. */ 702 while(!(ret = get_event(c))) 703 if(!_xcb_conn_wait(c, &c->in.event_cond, 0, 0)) 704 break; 705 706 _xcb_in_wake_up_next_reader(c); 707 pthread_mutex_unlock(&c->iolock); 708 return ret; 709 } 710 711 static xcb_generic_event_t *poll_for_next_event(xcb_connection_t *c, int queued) 712 { 713 xcb_generic_event_t *ret = 0; 714 if(!c->has_error) 715 { 716 pthread_mutex_lock(&c->iolock); 717 /* FIXME: follow X meets Z architecture changes. */ 718 ret = get_event(c); 719 if(!ret && !queued && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ 720 ret = get_event(c); 721 pthread_mutex_unlock(&c->iolock); 722 } 723 return ret; 724 } 725 726 xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c) 727 { 728 return poll_for_next_event(c, 0); 729 } 730 731 xcb_generic_event_t *xcb_poll_for_queued_event(xcb_connection_t *c) 732 { 733 return poll_for_next_event(c, 1); 734 } 735 736 xcb_generic_error_t *xcb_request_check(xcb_connection_t *c, xcb_void_cookie_t cookie) 737 { 738 uint64_t request; 739 xcb_generic_error_t *ret = 0; 740 void *reply; 741 if(c->has_error) 742 return 0; 743 pthread_mutex_lock(&c->iolock); 744 request = widen(c, cookie.sequence); 745 if (XCB_SEQUENCE_COMPARE(request, >, c->in.request_completed)) 746 { 747 if(XCB_SEQUENCE_COMPARE(request, >=, c->in.request_expected)) 748 { 749 _xcb_out_send_sync(c); 750 } 751 if (XCB_SEQUENCE_COMPARE(request, >=, c->out.request_expected_written)) 752 { 753 _xcb_out_flush_to(c, c->out.request); 754 } 755 } 756 reply = wait_for_reply(c, request, &ret); 757 assert(!reply); 758 pthread_mutex_unlock(&c->iolock); 759 return ret; 760 } 761 762 static xcb_generic_event_t *get_special_event(xcb_connection_t *c, 763 xcb_special_event_t *se) 764 { 765 xcb_generic_event_t *event = NULL; 766 struct event_list *events; 767 768 if ((events = se->events) != NULL) { 769 event = events->event; 770 if (!(se->events = events->next)) 771 se->events_tail = &se->events; 772 free (events); 773 } 774 return event; 775 } 776 777 xcb_generic_event_t *xcb_poll_for_special_event(xcb_connection_t *c, 778 xcb_special_event_t *se) 779 { 780 xcb_generic_event_t *event; 781 782 if(c->has_error) 783 return 0; 784 pthread_mutex_lock(&c->iolock); 785 event = get_special_event(c, se); 786 if(!event && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ 787 event = get_special_event(c, se); 788 pthread_mutex_unlock(&c->iolock); 789 return event; 790 } 791 792 xcb_generic_event_t *xcb_wait_for_special_event(xcb_connection_t *c, 793 xcb_special_event_t *se) 794 { 795 special_list special; 796 xcb_generic_event_t *event; 797 798 if(c->has_error) 799 return 0; 800 pthread_mutex_lock(&c->iolock); 801 802 insert_special(&c->in.special_waiters, &special, se); 803 804 /* get_special_event returns 0 on empty list. */ 805 while(!(event = get_special_event(c, se))) 806 if(!_xcb_conn_wait(c, &se->special_event_cond, 0, 0)) 807 break; 808 809 remove_special(&c->in.special_waiters, &special); 810 811 _xcb_in_wake_up_next_reader(c); 812 pthread_mutex_unlock(&c->iolock); 813 return event; 814 } 815 816 xcb_special_event_t * 817 xcb_register_for_special_xge(xcb_connection_t *c, 818 xcb_extension_t *ext, 819 uint32_t eid, 820 uint32_t *stamp) 821 { 822 xcb_special_event_t *se; 823 const xcb_query_extension_reply_t *ext_reply; 824 825 if(c->has_error) 826 return NULL; 827 ext_reply = xcb_get_extension_data(c, ext); 828 if (!ext_reply) 829 return NULL; 830 pthread_mutex_lock(&c->iolock); 831 for (se = c->in.special_events; se; se = se->next) { 832 if (se->extension == ext_reply->major_opcode && 833 se->eid == eid) { 834 pthread_mutex_unlock(&c->iolock); 835 return NULL; 836 } 837 } 838 se = calloc(1, sizeof(xcb_special_event_t)); 839 if (!se) { 840 pthread_mutex_unlock(&c->iolock); 841 return NULL; 842 } 843 844 se->extension = ext_reply->major_opcode; 845 se->eid = eid; 846 847 se->events = NULL; 848 se->events_tail = &se->events; 849 se->stamp = stamp; 850 851 pthread_cond_init(&se->special_event_cond, 0); 852 853 se->next = c->in.special_events; 854 c->in.special_events = se; 855 pthread_mutex_unlock(&c->iolock); 856 return se; 857 } 858 859 void 860 xcb_unregister_for_special_event(xcb_connection_t *c, 861 xcb_special_event_t *se) 862 { 863 xcb_special_event_t *s, **prev; 864 struct event_list *events, *next; 865 866 if (!se) 867 return; 868 869 if (c->has_error) 870 return; 871 872 pthread_mutex_lock(&c->iolock); 873 874 for (prev = &c->in.special_events; (s = *prev) != NULL; prev = &(s->next)) { 875 if (s == se) { 876 *prev = se->next; 877 for (events = se->events; events; events = next) { 878 next = events->next; 879 free (events->event); 880 free (events); 881 } 882 pthread_cond_destroy(&se->special_event_cond); 883 free (se); 884 break; 885 } 886 } 887 pthread_mutex_unlock(&c->iolock); 888 } 889 890 /* Private interface */ 891 892 int _xcb_in_init(_xcb_in *in) 893 { 894 if(pthread_cond_init(&in->event_cond, 0)) 895 return 0; 896 in->reading = 0; 897 898 in->queue_len = 0; 899 900 in->request_read = 0; 901 in->request_completed = 0; 902 903 in->replies = _xcb_map_new(); 904 if(!in->replies) 905 return 0; 906 907 in->current_reply_tail = &in->current_reply; 908 in->events_tail = &in->events; 909 in->pending_replies_tail = &in->pending_replies; 910 911 return 1; 912 } 913 914 void _xcb_in_destroy(_xcb_in *in) 915 { 916 pthread_cond_destroy(&in->event_cond); 917 free_reply_list(in->current_reply); 918 _xcb_map_delete(in->replies, (void (*)(void *)) free_reply_list); 919 while(in->events) 920 { 921 struct event_list *e = in->events; 922 in->events = e->next; 923 free(e->event); 924 free(e); 925 } 926 while(in->pending_replies) 927 { 928 pending_reply *pend = in->pending_replies; 929 in->pending_replies = pend->next; 930 free(pend); 931 } 932 } 933 934 void _xcb_in_wake_up_next_reader(xcb_connection_t *c) 935 { 936 int pthreadret; 937 if(c->in.readers) 938 pthreadret = pthread_cond_signal(c->in.readers->data); 939 else if(c->in.special_waiters) 940 pthreadret = pthread_cond_signal(&c->in.special_waiters->se->special_event_cond); 941 else 942 pthreadret = pthread_cond_signal(&c->in.event_cond); 943 assert(pthreadret == 0); 944 } 945 946 int _xcb_in_expect_reply(xcb_connection_t *c, uint64_t request, enum workarounds workaround, int flags) 947 { 948 pending_reply *pend = malloc(sizeof(pending_reply)); 949 assert(workaround != WORKAROUND_NONE || flags != 0); 950 if(!pend) 951 { 952 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 953 return 0; 954 } 955 pend->first_request = pend->last_request = request; 956 pend->workaround = workaround; 957 pend->flags = flags; 958 pend->next = 0; 959 *c->in.pending_replies_tail = pend; 960 c->in.pending_replies_tail = &pend->next; 961 return 1; 962 } 963 964 void _xcb_in_replies_done(xcb_connection_t *c) 965 { 966 struct pending_reply *pend; 967 if (c->in.pending_replies_tail != &c->in.pending_replies) 968 { 969 pend = container_of(c->in.pending_replies_tail, struct pending_reply, next); 970 if(pend->workaround == WORKAROUND_EXTERNAL_SOCKET_OWNER) 971 { 972 if (XCB_SEQUENCE_COMPARE(pend->first_request, <=, c->out.request)) { 973 pend->last_request = c->out.request; 974 pend->workaround = WORKAROUND_NONE; 975 } else { 976 /* The socket was taken, but no requests were actually sent 977 * so just discard the pending_reply that was created. 978 */ 979 struct pending_reply **prev_next = &c->in.pending_replies; 980 while (*prev_next != pend) 981 prev_next = &(*prev_next)->next; 982 *prev_next = NULL; 983 c->in.pending_replies_tail = prev_next; 984 free(pend); 985 } 986 } 987 } 988 } 989 990 int _xcb_in_read(xcb_connection_t *c) 991 { 992 int n; 993 994 #if HAVE_SENDMSG 995 struct iovec iov = { 996 .iov_base = c->in.queue + c->in.queue_len, 997 .iov_len = sizeof(c->in.queue) - c->in.queue_len, 998 }; 999 union { 1000 struct cmsghdr cmsghdr; 1001 char buf[CMSG_SPACE(XCB_MAX_PASS_FD * sizeof(int))]; 1002 } cmsgbuf; 1003 struct msghdr msg = { 1004 .msg_name = NULL, 1005 .msg_namelen = 0, 1006 .msg_iov = &iov, 1007 .msg_iovlen = 1, 1008 .msg_control = cmsgbuf.buf, 1009 .msg_controllen = CMSG_SPACE(sizeof(int) * (XCB_MAX_PASS_FD - c->in.in_fd.nfd)), 1010 }; 1011 n = recvmsg(c->fd, &msg, 0); 1012 1013 /* Check for truncation errors. Only MSG_CTRUNC is 1014 * probably possible here, which would indicate that 1015 * the sender tried to transmit more than XCB_MAX_PASS_FD 1016 * file descriptors. 1017 */ 1018 if (msg.msg_flags & (MSG_TRUNC|MSG_CTRUNC)) { 1019 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_FDPASSING_FAILED); 1020 return 0; 1021 } 1022 #else 1023 n = recv(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len, 0); 1024 #endif 1025 if(n > 0) { 1026 #if HAVE_SENDMSG 1027 struct cmsghdr *hdr; 1028 1029 if (msg.msg_controllen >= sizeof (struct cmsghdr)) { 1030 for (hdr = CMSG_FIRSTHDR(&msg); hdr; hdr = CMSG_NXTHDR(&msg, hdr)) { 1031 if (hdr->cmsg_level == SOL_SOCKET && hdr->cmsg_type == SCM_RIGHTS) { 1032 int nfd = (hdr->cmsg_len - CMSG_LEN(0)) / sizeof (int); 1033 memcpy(&c->in.in_fd.fd[c->in.in_fd.nfd], CMSG_DATA(hdr), nfd * sizeof (int)); 1034 c->in.in_fd.nfd += nfd; 1035 } 1036 } 1037 } 1038 #endif 1039 c->in.total_read += n; 1040 c->in.queue_len += n; 1041 } 1042 while(read_packet(c)) 1043 /* empty */; 1044 #if HAVE_SENDMSG 1045 if (c->in.in_fd.nfd) { 1046 c->in.in_fd.nfd -= c->in.in_fd.ifd; 1047 memmove(&c->in.in_fd.fd[0], 1048 &c->in.in_fd.fd[c->in.in_fd.ifd], 1049 c->in.in_fd.nfd * sizeof (int)); 1050 c->in.in_fd.ifd = 0; 1051 1052 /* If we have any left-over file descriptors after emptying 1053 * the input buffer, then the server sent some that we weren't 1054 * expecting. Close them and mark the connection as broken; 1055 */ 1056 if (c->in.queue_len == 0 && c->in.in_fd.nfd != 0) { 1057 int i; 1058 for (i = 0; i < c->in.in_fd.nfd; i++) 1059 close(c->in.in_fd.fd[i]); 1060 _xcb_conn_shutdown(c, XCB_CONN_CLOSED_FDPASSING_FAILED); 1061 return 0; 1062 } 1063 } 1064 #endif 1065 #ifndef _WIN32 1066 if((n > 0) || (n < 0 && (errno == EAGAIN || errno == EINTR))) 1067 #else 1068 if((n > 0) || (n < 0 && WSAGetLastError() == WSAEWOULDBLOCK)) 1069 #endif /* !_WIN32 */ 1070 return 1; 1071 _xcb_conn_shutdown(c, XCB_CONN_ERROR); 1072 return 0; 1073 } 1074 1075 int _xcb_in_read_block(xcb_connection_t *c, void *buf, int len) 1076 { 1077 int done = c->in.queue_len; 1078 if(len < done) 1079 done = len; 1080 1081 memcpy(buf, c->in.queue, done); 1082 c->in.queue_len -= done; 1083 memmove(c->in.queue, c->in.queue + done, c->in.queue_len); 1084 1085 if(len > done) 1086 { 1087 int ret = read_block(c->fd, (char *) buf + done, len - done); 1088 if(ret <= 0) 1089 { 1090 _xcb_conn_shutdown(c, XCB_CONN_ERROR); 1091 return ret; 1092 } 1093 } 1094 1095 return len; 1096 } 1097
Indexes created Fri Jul 03 00:25:33 UTC 2026