1 /* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp.
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:
10 * The above copyright notice and this permission notice shall be included in
11 * all copies or substantial portions of the Software.
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.
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.
26 /* Stuff that reads stuff from the server. */
33 #include <sys/select.h>
44 xcb_generic_event_t *event;
45 struct event_list *next;
50 struct reply_list *next;
53 typedef struct pending_reply {
55 enum workarounds workaround;
57 struct pending_reply *next;
60 typedef struct reader_list {
63 struct reader_list *next;
66 static void wake_up_next_reader(xcb_connection_t *c)
70 pthreadret = pthread_cond_signal(c->in.readers->data);
72 pthreadret = pthread_cond_signal(&c->in.event_cond);
73 assert(pthreadret == 0);
76 static int read_packet(xcb_connection_t *c)
78 xcb_generic_reply_t genrep;
81 pending_reply *pend = 0;
82 struct event_list *event;
84 /* Wait for there to be enough data for us to read a whole packet */
85 if(c->in.queue_len < length)
88 /* Get the response type, length, and sequence number. */
89 memcpy(&genrep, c->in.queue, sizeof(genrep));
91 /* Compute 32-bit sequence number of this packet. */
92 if((genrep.response_type & 0x7f) != XCB_KEYMAP_NOTIFY)
94 unsigned int lastread = c->in.request_read;
95 c->in.request_read = (lastread & 0xffff0000) | genrep.sequence;
96 if(XCB_SEQUENCE_COMPARE(c->in.request_read, <, lastread))
97 c->in.request_read += 0x10000;
98 if(XCB_SEQUENCE_COMPARE(c->in.request_read, >, c->in.request_expected))
99 c->in.request_expected = c->in.request_read;
101 if(c->in.request_read != lastread)
103 if(c->in.current_reply)
105 _xcb_map_put(c->in.replies, lastread, c->in.current_reply);
106 c->in.current_reply = 0;
107 c->in.current_reply_tail = &c->in.current_reply;
109 c->in.request_completed = c->in.request_read - 1;
112 while(c->in.pending_replies &&
113 XCB_SEQUENCE_COMPARE (c->in.pending_replies->request, <=, c->in.request_completed))
115 pending_reply *oldpend = c->in.pending_replies;
116 c->in.pending_replies = oldpend->next;
118 c->in.pending_replies_tail = &c->in.pending_replies;
122 if(genrep.response_type == XCB_ERROR)
123 c->in.request_completed = c->in.request_read;
126 if(genrep.response_type == XCB_ERROR || genrep.response_type == XCB_REPLY)
128 pend = c->in.pending_replies;
129 if(pend && pend->request != c->in.request_read)
133 /* For reply packets, check that the entire packet is available. */
134 if(genrep.response_type == XCB_REPLY)
136 if(pend && pend->workaround == WORKAROUND_GLX_GET_FB_CONFIGS_BUG)
138 uint32_t *p = (uint32_t *) c->in.queue;
139 genrep.length = p[2] * p[3] * 2;
141 length += genrep.length * 4;
144 buf = malloc(length + (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t)));
147 _xcb_conn_shutdown(c);
150 if(_xcb_in_read_block(c, buf, length) <= 0)
155 if(pend && (pend->flags & XCB_REQUEST_DISCARD_REPLY))
161 if(genrep.response_type != XCB_REPLY)
162 ((xcb_generic_event_t *) buf)->full_sequence = c->in.request_read;
164 /* reply, or checked error */
165 if( genrep.response_type == XCB_REPLY ||
166 (genrep.response_type == XCB_ERROR && pend && (pend->flags & XCB_REQUEST_CHECKED)))
169 struct reply_list *cur = malloc(sizeof(struct reply_list));
172 _xcb_conn_shutdown(c);
177 *c->in.current_reply_tail = cur;
178 c->in.current_reply_tail = &cur->next;
179 for(reader = c->in.readers;
181 XCB_SEQUENCE_COMPARE(reader->request, <=, c->in.request_read);
182 reader = reader->next)
184 if(reader->request == c->in.request_read)
186 pthread_cond_signal(reader->data);
193 /* event, or unchecked error */
194 event = malloc(sizeof(struct event_list));
197 _xcb_conn_shutdown(c);
203 *c->in.events_tail = event;
204 c->in.events_tail = &event->next;
205 pthread_cond_signal(&c->in.event_cond);
206 return 1; /* I have something for you... */
209 static xcb_generic_event_t *get_event(xcb_connection_t *c)
211 struct event_list *cur = c->in.events;
212 xcb_generic_event_t *ret;
216 c->in.events = cur->next;
218 c->in.events_tail = &c->in.events;
223 static void free_reply_list(struct reply_list *head)
227 struct reply_list *cur = head;
234 static int read_block(const int fd, void *buf, const size_t len)
239 int ret = read(fd, ((char *) buf) + done, len - done);
242 if(ret < 0 && errno == EAGAIN)
248 ret = select(fd + 1, &fds, 0, 0, 0);
249 } while (ret == -1 && errno == EINTR);
257 static int poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error)
259 struct reply_list *head;
261 /* If an error occurred when issuing the request, fail immediately. */
264 /* We've read requests past the one we want, so if it has replies we have
265 * them all and they're in the replies map. */
266 else if(XCB_SEQUENCE_COMPARE(request, <, c->in.request_read))
268 head = _xcb_map_remove(c->in.replies, request);
269 if(head && head->next)
270 _xcb_map_put(c->in.replies, request, head->next);
272 /* We're currently processing the responses to the request we want, and we
273 * have a reply ready to return. So just return it without blocking. */
274 else if(request == c->in.request_read && c->in.current_reply)
276 head = c->in.current_reply;
277 c->in.current_reply = head->next;
279 c->in.current_reply_tail = &c->in.current_reply;
281 /* We know this request can't have any more replies, and we've already
282 * established it doesn't have a reply now. Don't bother blocking. */
283 else if(request == c->in.request_completed)
285 /* We may have more replies on the way for this request: block until we're
296 if(((xcb_generic_reply_t *) head->reply)->response_type == XCB_ERROR)
299 *error = head->reply;
304 *reply = head->reply;
312 /* Public interface */
314 void *xcb_wait_for_reply(xcb_connection_t *c, unsigned int request, xcb_generic_error_t **e)
324 /* If this request has not been written yet, write it. */
325 if(_xcb_out_flush_to(c, request))
327 pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
329 reader_list **prev_reader;
331 for(prev_reader = &c->in.readers;
333 XCB_SEQUENCE_COMPARE ((*prev_reader)->request, <=, request);
334 prev_reader = &(*prev_reader)->next)
338 reader.request = request;
340 reader.next = *prev_reader;
341 *prev_reader = &reader;
343 while(!poll_for_reply(c, request, &ret, e))
344 if(!_xcb_conn_wait(c, &cond, 0, 0))
347 for(prev_reader = &c->in.readers;
349 XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, request);
350 prev_reader = &(*prev_reader)->next)
352 if(*prev_reader == &reader)
354 *prev_reader = (*prev_reader)->next;
358 pthread_cond_destroy(&cond);
361 wake_up_next_reader(c);
366 int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error)
374 return 1; /* would not block */
378 ret = poll_for_reply(c, request, reply, error);
383 xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c)
385 xcb_generic_event_t *ret;
389 /* get_event returns 0 on empty list. */
390 while(!(ret = get_event(c)))
391 if(!_xcb_conn_wait(c, &c->in.event_cond, 0, 0))
394 wake_up_next_reader(c);
399 xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c)
401 xcb_generic_event_t *ret = 0;
405 /* FIXME: follow X meets Z architecture changes. */
406 if(_xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */
413 xcb_generic_error_t *xcb_request_check(xcb_connection_t *c, xcb_void_cookie_t cookie)
415 /* FIXME: this could hold the lock to avoid syncing unnecessarily, but
416 * that would require factoring the locking out of xcb_get_input_focus,
417 * xcb_get_input_focus_reply, and xcb_wait_for_reply. */
418 xcb_generic_error_t *ret;
422 if(XCB_SEQUENCE_COMPARE(cookie.sequence,>,c->in.request_expected)
423 && XCB_SEQUENCE_COMPARE(cookie.sequence,>,c->in.request_completed))
425 free(xcb_get_input_focus_reply(c, xcb_get_input_focus(c), &ret));
428 reply = xcb_wait_for_reply(c, cookie.sequence, &ret);
433 /* Private interface */
435 int _xcb_in_init(_xcb_in *in)
437 if(pthread_cond_init(&in->event_cond, 0))
443 in->request_read = 0;
444 in->request_completed = 0;
446 in->replies = _xcb_map_new();
450 in->current_reply_tail = &in->current_reply;
451 in->events_tail = &in->events;
452 in->pending_replies_tail = &in->pending_replies;
457 void _xcb_in_destroy(_xcb_in *in)
459 pthread_cond_destroy(&in->event_cond);
460 free_reply_list(in->current_reply);
461 _xcb_map_delete(in->replies, (void (*)(void *)) free_reply_list);
464 struct event_list *e = in->events;
465 in->events = e->next;
469 while(in->pending_replies)
471 pending_reply *pend = in->pending_replies;
472 in->pending_replies = pend->next;
477 int _xcb_in_expect_reply(xcb_connection_t *c, unsigned int request, enum workarounds workaround, int flags)
479 pending_reply *pend = malloc(sizeof(pending_reply));
480 assert(workaround != WORKAROUND_NONE || flags != 0);
483 _xcb_conn_shutdown(c);
486 pend->request = request;
487 pend->workaround = workaround;
490 *c->in.pending_replies_tail = pend;
491 c->in.pending_replies_tail = &pend->next;
495 int _xcb_in_read(xcb_connection_t *c)
497 int n = read(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len);
499 c->in.queue_len += n;
500 while(read_packet(c))
502 if((n > 0) || (n < 0 && errno == EAGAIN))
504 _xcb_conn_shutdown(c);
508 int _xcb_in_read_block(xcb_connection_t *c, void *buf, int len)
510 int done = c->in.queue_len;
514 memcpy(buf, c->in.queue, done);
515 c->in.queue_len -= done;
516 memmove(c->in.queue, c->in.queue + done, c->in.queue_len);
520 int ret = read_block(c->fd, (char *) buf + done, len - done);
523 _xcb_conn_shutdown(c);