diff options
Diffstat (limited to 'libxcb/src/xcb_in.c')
| -rw-r--r-- | libxcb/src/xcb_in.c | 1429 |
1 files changed, 700 insertions, 729 deletions
diff --git a/libxcb/src/xcb_in.c b/libxcb/src/xcb_in.c index a49efd5db..4acc3a27d 100644 --- a/libxcb/src/xcb_in.c +++ b/libxcb/src/xcb_in.c @@ -1,729 +1,700 @@ -/* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
- * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- *
- * Except as contained in this notice, the names of the authors or their
- * institutions shall not be used in advertising or otherwise to promote the
- * sale, use or other dealings in this Software without prior written
- * authorization from the authors.
- */
-
-/* Stuff that reads stuff from the server. */
-
-#include <assert.h>
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <errno.h>
-
-#include "xcb.h"
-#include "xcbext.h"
-#include "xcbint.h"
-#if USE_POLL
-#include <poll.h>
-#endif
-#ifndef _WIN32
-#include <sys/select.h>
-#include <sys/socket.h>
-#endif
-
-#ifdef _WIN32
-#include "xcb_windefs.h"
-#endif /* _WIN32 */
-
-#define XCB_ERROR 0
-#define XCB_REPLY 1
-#define XCB_XGE_EVENT 35
-
-/* required for compiling for Win32 using MinGW */
-#ifndef MSG_WAITALL
-#define MSG_WAITALL 0
-#endif
-
-struct event_list {
- uint64_t sequence;
- xcb_generic_event_t *event;
- struct event_list *next;
-};
-
-struct reply_list {
- void *reply;
- struct reply_list *next;
-};
-
-typedef struct pending_reply {
- uint64_t first_request;
- uint64_t last_request;
- enum workarounds workaround;
- int flags;
- struct pending_reply *next;
-} pending_reply;
-
-typedef struct reader_list {
- uint64_t request;
- pthread_cond_t *data;
- struct reader_list *next;
-} reader_list;
-
-static void remove_finished_readers(reader_list **prev_reader, uint64_t completed)
-{
- while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, completed))
- {
- /* If you don't have what you're looking for now, you never
- * will. Wake up and leave me alone. */
- pthread_cond_signal((*prev_reader)->data);
- *prev_reader = (*prev_reader)->next;
- }
-}
-
-static int read_packet(xcb_connection_t *c)
-{
- xcb_generic_reply_t genrep;
- int length = 32;
- int eventlength = 0; /* length after first 32 bytes for GenericEvents */
- void *buf;
- pending_reply *pend = 0;
- struct event_list *event;
-
- /* Wait for there to be enough data for us to read a whole packet */
- if(c->in.queue_len < length)
- return 0;
-
- /* Get the response type, length, and sequence number. */
- memcpy(&genrep, c->in.queue, sizeof(genrep));
-
- /* Compute 32-bit sequence number of this packet. */
- if((genrep.response_type & 0x7f) != XCB_KEYMAP_NOTIFY)
- {
- uint64_t lastread = c->in.request_read;
- c->in.request_read = (lastread & UINT64_C(0xffffffffffff0000)) | genrep.sequence;
- if(XCB_SEQUENCE_COMPARE(c->in.request_read, <, lastread))
- c->in.request_read += 0x10000;
- if(XCB_SEQUENCE_COMPARE(c->in.request_read, >, c->in.request_expected))
- c->in.request_expected = c->in.request_read;
-
- if(c->in.request_read != lastread)
- {
- if(c->in.current_reply)
- {
- _xcb_map_put(c->in.replies, lastread, c->in.current_reply);
- c->in.current_reply = 0;
- c->in.current_reply_tail = &c->in.current_reply;
- }
- c->in.request_completed = c->in.event_responses_completed = c->in.request_read - 1;
- }
-
- while(c->in.pending_replies &&
- c->in.pending_replies->workaround != WORKAROUND_EXTERNAL_SOCKET_OWNER &&
- XCB_SEQUENCE_COMPARE (c->in.pending_replies->last_request, <=, c->in.request_completed))
- {
- pending_reply *oldpend = c->in.pending_replies;
- c->in.pending_replies = oldpend->next;
- if(!oldpend->next)
- c->in.pending_replies_tail = &c->in.pending_replies;
- free(oldpend);
- }
-
- if(genrep.response_type == XCB_ERROR)
- c->in.request_completed = c->in.event_responses_completed = c->in.request_read;
- else if(genrep.response_type == XCB_REPLY)
- c->in.event_responses_completed = c->in.request_read;
-
- remove_finished_readers(&c->in.readers, c->in.request_completed);
- remove_finished_readers(&c->in.event_readers, c->in.event_responses_completed);
- }
-
- if(genrep.response_type == XCB_ERROR || genrep.response_type == XCB_REPLY)
- {
- pend = c->in.pending_replies;
- if(pend &&
- !(XCB_SEQUENCE_COMPARE(pend->first_request, <=, c->in.request_read) &&
- (pend->workaround == WORKAROUND_EXTERNAL_SOCKET_OWNER ||
- XCB_SEQUENCE_COMPARE(c->in.request_read, <=, pend->last_request))))
- pend = 0;
- }
-
- /* For reply packets, check that the entire packet is available. */
- if(genrep.response_type == XCB_REPLY)
- {
- if(pend && pend->workaround == WORKAROUND_GLX_GET_FB_CONFIGS_BUG)
- {
- uint32_t *p = (uint32_t *) c->in.queue;
- genrep.length = p[2] * p[3] * 2;
- }
- length += genrep.length * 4;
- }
-
- /* XGE events may have sizes > 32 */
- if (genrep.response_type == XCB_XGE_EVENT)
- eventlength = genrep.length * 4;
-
- buf = malloc(length + eventlength +
- (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t)));
- if(!buf)
- {
- _xcb_conn_shutdown(c);
- return 0;
- }
-
- if(_xcb_in_read_block(c, buf, length) <= 0)
- {
- free(buf);
- return 0;
- }
-
- /* pull in XGE event data if available, append after event struct */
- if (eventlength)
- {
- if(_xcb_in_read_block(c, &((xcb_generic_event_t*)buf)[1], eventlength) <= 0)
- {
- free(buf);
- return 0;
- }
- }
-
- if(pend && (pend->flags & XCB_REQUEST_DISCARD_REPLY))
- {
- free(buf);
- return 1;
- }
-
- if(genrep.response_type != XCB_REPLY)
- ((xcb_generic_event_t *) buf)->full_sequence = c->in.request_read;
-
- /* reply, or checked error */
- if( genrep.response_type == XCB_REPLY ||
- (genrep.response_type == XCB_ERROR && pend && (pend->flags & XCB_REQUEST_CHECKED)))
- {
- struct reply_list *cur = malloc(sizeof(struct reply_list));
- if(!cur)
- {
- _xcb_conn_shutdown(c);
- free(buf);
- return 0;
- }
- cur->reply = buf;
- cur->next = 0;
- *c->in.current_reply_tail = cur;
- c->in.current_reply_tail = &cur->next;
- if(c->in.readers && c->in.readers->request == c->in.request_read)
- pthread_cond_signal(c->in.readers->data);
- return 1;
- }
-
- /* event, or unchecked error */
- event = malloc(sizeof(struct event_list));
- if(!event)
- {
- _xcb_conn_shutdown(c);
- free(buf);
- return 0;
- }
- event->sequence = c->in.request_read;
- event->event = buf;
- event->next = 0;
- *c->in.events_tail = event;
- c->in.events_tail = &event->next;
- if(c->in.event_readers)
- pthread_cond_signal(c->in.event_readers->data);
- else
- pthread_cond_signal(&c->in.event_cond);
- return 1; /* I have something for you... */
-}
-
-static xcb_generic_event_t *get_event(xcb_connection_t *c)
-{
- struct event_list *cur = c->in.events;
- xcb_generic_event_t *ret;
- if(!c->in.events)
- return 0;
- ret = cur->event;
- c->in.events = cur->next;
- if(!cur->next)
- c->in.events_tail = &c->in.events;
- free(cur);
- return ret;
-}
-
-static void free_reply_list(struct reply_list *head)
-{
- while(head)
- {
- struct reply_list *cur = head;
- head = cur->next;
- free(cur->reply);
- free(cur);
- }
-}
-
-static int read_block(const int fd, void *buf, const ssize_t len)
-{
- int done = 0;
- while(done < len)
- {
- int ret = recv(fd, ((char *) buf) + done, len - done,MSG_WAITALL);
- if(ret > 0)
- done += ret;
-#ifndef _WIN32
- if(ret < 0 && errno == EAGAIN)
-#else
- if(ret == SOCKET_ERROR && WSAGetLastError() == WSAEWOULDBLOCK)
-#endif /* !_Win32 */
- {
-#if USE_POLL
- struct pollfd pfd;
- pfd.fd = fd;
- pfd.events = POLLIN;
- pfd.revents = 0;
- do {
- ret = poll(&pfd, 1, -1);
- } while (ret == -1 && errno == EINTR);
-#else
- fd_set fds;
- FD_ZERO(&fds);
- FD_SET(fd, &fds);
-
- /* Initializing errno here makes sure that for Win32 this loop will execute only once */
- errno = 0;
- do {
- ret = select(fd + 1, &fds, 0, 0, 0);
- } while (ret == -1 && errno == EINTR);
-#endif /* USE_POLL */
- }
- if(ret <= 0)
- return ret;
- }
- return len;
-}
-
-static int poll_for_reply(xcb_connection_t *c, uint64_t request, void **reply, xcb_generic_error_t **error)
-{
- struct reply_list *head;
-
- /* If an error occurred when issuing the request, fail immediately. */
- if(!request)
- head = 0;
- /* We've read requests past the one we want, so if it has replies we have
- * them all and they're in the replies map. */
- else if(XCB_SEQUENCE_COMPARE(request, <, c->in.request_read))
- {
- head = _xcb_map_remove(c->in.replies, request);
- if(head && head->next)
- _xcb_map_put(c->in.replies, request, head->next);
- }
- /* We're currently processing the responses to the request we want, and we
- * have a reply ready to return. So just return it without blocking. */
- else if(request == c->in.request_read && c->in.current_reply)
- {
- head = c->in.current_reply;
- c->in.current_reply = head->next;
- if(!head->next)
- c->in.current_reply_tail = &c->in.current_reply;
- }
- /* We know this request can't have any more replies, and we've already
- * established it doesn't have a reply now. Don't bother blocking. */
- else if(request == c->in.request_completed)
- head = 0;
- /* We may have more replies on the way for this request: block until we're
- * sure. */
- else
- return 0;
-
- if(error)
- *error = 0;
- *reply = 0;
-
- if(head)
- {
- if(((xcb_generic_reply_t *) head->reply)->response_type == XCB_ERROR)
- {
- if(error)
- *error = head->reply;
- else
- free(head->reply);
- }
- else
- *reply = head->reply;
-
- free(head);
- }
-
- return 1;
-}
-
-static void insert_reader(reader_list **prev_reader, reader_list *reader, uint64_t request, pthread_cond_t *cond)
-{
- while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, request))
- prev_reader = &(*prev_reader)->next;
- reader->request = request;
- reader->data = cond;
- reader->next = *prev_reader;
- *prev_reader = reader;
-}
-
-static void remove_reader(reader_list **prev_reader, reader_list *reader)
-{
- while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, reader->request))
- if(*prev_reader == reader)
- {
- *prev_reader = (*prev_reader)->next;
- break;
- }
-}
-
-static void *wait_for_reply(xcb_connection_t *c, uint64_t request, xcb_generic_error_t **e)
-{
- void *ret = 0;
-
- /* If this request has not been written yet, write it. */
- if(c->out.return_socket || _xcb_out_flush_to(c, request))
- {
- pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
- reader_list reader;
-
- insert_reader(&c->in.readers, &reader, request, &cond);
-
- while(!poll_for_reply(c, request, &ret, e))
- if(!_xcb_conn_wait(c, &cond, 0, 0))
- break;
-
- remove_reader(&c->in.readers, &reader);
- pthread_cond_destroy(&cond);
- }
-
- _xcb_in_wake_up_next_reader(c);
- return ret;
-}
-
-static uint64_t widen(xcb_connection_t *c, unsigned int request)
-{
- uint64_t widened_request = (c->out.request & UINT64_C(0xffffffff00000000)) | request;
- if(widened_request > c->out.request)
- widened_request -= UINT64_C(1) << 32;
- return widened_request;
-}
-
-/* Public interface */
-
-void *xcb_wait_for_reply(xcb_connection_t *c, unsigned int request, xcb_generic_error_t **e)
-{
- void *ret;
- if(e)
- *e = 0;
- if(c->has_error)
- return 0;
-
- pthread_mutex_lock(&c->iolock);
- ret = wait_for_reply(c, widen(c, request), e);
- pthread_mutex_unlock(&c->iolock);
- return ret;
-}
-
-static void insert_pending_discard(xcb_connection_t *c, pending_reply **prev_next, uint64_t seq)
-{
- pending_reply *pend;
- pend = malloc(sizeof(*pend));
- if(!pend)
- {
- _xcb_conn_shutdown(c);
- return;
- }
-
- pend->first_request = seq;
- pend->last_request = seq;
- pend->workaround = 0;
- pend->flags = XCB_REQUEST_DISCARD_REPLY;
- pend->next = *prev_next;
- *prev_next = pend;
-
- if(!pend->next)
- c->in.pending_replies_tail = &pend->next;
-}
-
-static void discard_reply(xcb_connection_t *c, uint64_t request)
-{
- void *reply;
- pending_reply **prev_pend;
-
- /* Free any replies or errors that we've already read. Stop if
- * xcb_wait_for_reply would block or we've run out of replies. */
- while(poll_for_reply(c, request, &reply, 0) && reply)
- free(reply);
-
- /* If we've proven there are no more responses coming, we're done. */
- if(XCB_SEQUENCE_COMPARE(request, <=, c->in.request_completed))
- return;
-
- /* Walk the list of pending requests. Mark the first match for deletion. */
- for(prev_pend = &c->in.pending_replies; *prev_pend; prev_pend = &(*prev_pend)->next)
- {
- if(XCB_SEQUENCE_COMPARE((*prev_pend)->first_request, >, request))
- break;
-
- if((*prev_pend)->first_request == request)
- {
- /* Pending reply found. Mark for discard: */
- (*prev_pend)->flags |= XCB_REQUEST_DISCARD_REPLY;
- return;
- }
- }
-
- /* Pending reply not found (likely due to _unchecked request). Create one: */
- insert_pending_discard(c, prev_pend, request);
-}
-
-void xcb_discard_reply(xcb_connection_t *c, unsigned int sequence)
-{
- if(c->has_error)
- return;
-
- /* If an error occurred when issuing the request, fail immediately. */
- if(!sequence)
- return;
-
- pthread_mutex_lock(&c->iolock);
- discard_reply(c, widen(c, sequence));
- pthread_mutex_unlock(&c->iolock);
-}
-
-int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error)
-{
- int ret;
- if(c->has_error)
- {
- *reply = 0;
- if(error)
- *error = 0;
- return 1; /* would not block */
- }
- assert(reply != 0);
- pthread_mutex_lock(&c->iolock);
- ret = poll_for_reply(c, widen(c, request), reply, error);
- pthread_mutex_unlock(&c->iolock);
- return ret;
-}
-
-xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c)
-{
- xcb_generic_event_t *ret;
- if(c->has_error)
- return 0;
- pthread_mutex_lock(&c->iolock);
- /* get_event returns 0 on empty list. */
- while(!(ret = get_event(c)))
- if(!_xcb_conn_wait(c, &c->in.event_cond, 0, 0))
- break;
-
- _xcb_in_wake_up_next_reader(c);
- pthread_mutex_unlock(&c->iolock);
- return ret;
-}
-
-xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c)
-{
- xcb_generic_event_t *ret = 0;
- if(!c->has_error)
- {
- pthread_mutex_lock(&c->iolock);
- /* FIXME: follow X meets Z architecture changes. */
- ret = get_event(c);
- if(!ret && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */
- ret = get_event(c);
- pthread_mutex_unlock(&c->iolock);
- }
- return ret;
-}
-
-static xcb_generic_event_t *get_event_until(xcb_connection_t *c, uint64_t request)
-{
- if(c->in.events && XCB_SEQUENCE_COMPARE(c->in.events->sequence, <=, request))
- return get_event(c);
- return 0;
-}
-
-xcb_generic_event_t *xcb_wait_for_event_until(xcb_connection_t *c, unsigned int request)
-{
- pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
- reader_list reader;
- xcb_generic_event_t *ret;
- if(c->has_error)
- return 0;
- pthread_mutex_lock(&c->iolock);
-
- insert_reader(&c->in.event_readers, &reader, widen(c, request), &cond);
-
- while(!(ret = get_event_until(c, reader.request)) && XCB_SEQUENCE_COMPARE(c->in.event_responses_completed, <, reader.request))
- if(!_xcb_conn_wait(c, &cond, 0, 0))
- break;
-
- remove_reader(&c->in.event_readers, &reader);
- pthread_cond_destroy(&cond);
- _xcb_in_wake_up_next_reader(c);
- pthread_mutex_unlock(&c->iolock);
- return ret;
-}
-
-xcb_generic_error_t *xcb_request_check(xcb_connection_t *c, xcb_void_cookie_t cookie)
-{
- uint64_t request;
- xcb_generic_error_t *ret = 0;
- void *reply;
- if(c->has_error)
- return 0;
- pthread_mutex_lock(&c->iolock);
- request = widen(c, cookie.sequence);
- if(XCB_SEQUENCE_COMPARE(request, >=, c->in.request_expected)
- && XCB_SEQUENCE_COMPARE(request, >, c->in.request_completed))
- {
- _xcb_out_send_sync(c);
- _xcb_out_flush_to(c, c->out.request);
- }
- reply = wait_for_reply(c, request, &ret);
- assert(!reply);
- pthread_mutex_unlock(&c->iolock);
- return ret;
-}
-
-/* Private interface */
-
-int _xcb_in_init(_xcb_in *in)
-{
- if(pthread_cond_init(&in->event_cond, 0))
- return 0;
- in->reading = 0;
-
- in->queue_len = 0;
-
- in->request_read = 0;
- in->request_completed = 0;
-
- in->replies = _xcb_map_new();
- if(!in->replies)
- return 0;
-
- in->current_reply_tail = &in->current_reply;
- in->events_tail = &in->events;
- in->pending_replies_tail = &in->pending_replies;
-
- return 1;
-}
-
-void _xcb_in_destroy(_xcb_in *in)
-{
- pthread_cond_destroy(&in->event_cond);
- free_reply_list(in->current_reply);
- _xcb_map_delete(in->replies, (void (*)(void *)) free_reply_list);
- while(in->events)
- {
- struct event_list *e = in->events;
- in->events = e->next;
- free(e->event);
- free(e);
- }
- while(in->pending_replies)
- {
- pending_reply *pend = in->pending_replies;
- in->pending_replies = pend->next;
- free(pend);
- }
-}
-
-void _xcb_in_wake_up_next_reader(xcb_connection_t *c)
-{
- int pthreadret;
- if(c->in.readers)
- pthreadret = pthread_cond_signal(c->in.readers->data);
- else if(c->in.event_readers)
- pthreadret = pthread_cond_signal(c->in.event_readers->data);
- else
- pthreadret = pthread_cond_signal(&c->in.event_cond);
- assert(pthreadret == 0);
-}
-
-int _xcb_in_expect_reply(xcb_connection_t *c, uint64_t request, enum workarounds workaround, int flags)
-{
- pending_reply *pend = malloc(sizeof(pending_reply));
- assert(workaround != WORKAROUND_NONE || flags != 0);
- if(!pend)
- {
- _xcb_conn_shutdown(c);
- return 0;
- }
- pend->first_request = pend->last_request = request;
- pend->workaround = workaround;
- pend->flags = flags;
- pend->next = 0;
- *c->in.pending_replies_tail = pend;
- c->in.pending_replies_tail = &pend->next;
- return 1;
-}
-
-void _xcb_in_replies_done(xcb_connection_t *c)
-{
- struct pending_reply *pend;
- if (c->in.pending_replies_tail != &c->in.pending_replies)
- {
- pend = container_of(c->in.pending_replies_tail, struct pending_reply, next);
- if(pend->workaround == WORKAROUND_EXTERNAL_SOCKET_OWNER)
- {
- pend->last_request = c->out.request;
- pend->workaround = WORKAROUND_NONE;
- }
- }
-}
-
-int _xcb_in_read(xcb_connection_t *c)
-{
- int n = recv(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len,MSG_WAITALL);
- if(n > 0)
- c->in.queue_len += n;
- while(read_packet(c))
- /* empty */;
-#ifndef _WIN32
- if((n > 0) || (n < 0 && errno == EAGAIN))
-#else
- if((n > 0) || (n < 0 && WSAGetLastError() == WSAEWOULDBLOCK))
-#endif /* !_WIN32 */
- return 1;
- _xcb_conn_shutdown(c);
- return 0;
-}
-
-int _xcb_in_read_block(xcb_connection_t *c, void *buf, int len)
-{
- int done = c->in.queue_len;
- if(len < done)
- done = len;
-
- memcpy(buf, c->in.queue, done);
- c->in.queue_len -= done;
- memmove(c->in.queue, c->in.queue + done, c->in.queue_len);
-
- if(len > done)
- {
- int ret = read_block(c->fd, (char *) buf + done, len - done);
- if(ret <= 0)
- {
- _xcb_conn_shutdown(c);
- return ret;
- }
- }
-
- return len;
-}
+/* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * Except as contained in this notice, the names of the authors or their + * institutions shall not be used in advertising or otherwise to promote the + * sale, use or other dealings in this Software without prior written + * authorization from the authors. + */ + +/* Stuff that reads stuff from the server. */ + +#include <assert.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <stdio.h> +#include <errno.h> + +#include "xcb.h" +#include "xcbext.h" +#include "xcbint.h" +#if USE_POLL +#include <poll.h> +#endif +#ifndef _WIN32 +#include <sys/select.h> +#include <sys/socket.h> +#endif + +#ifdef _WIN32 +#include "xcb_windefs.h" +#endif /* _WIN32 */ + +#define XCB_ERROR 0 +#define XCB_REPLY 1 +#define XCB_XGE_EVENT 35 + +/* required for compiling for Win32 using MinGW */ +#ifndef MSG_WAITALL +#define MSG_WAITALL 0 +#endif + +struct event_list { + xcb_generic_event_t *event; + struct event_list *next; +}; + +struct reply_list { + void *reply; + struct reply_list *next; +}; + +typedef struct pending_reply { + uint64_t first_request; + uint64_t last_request; + enum workarounds workaround; + int flags; + struct pending_reply *next; +} pending_reply; + +typedef struct reader_list { + uint64_t request; + pthread_cond_t *data; + struct reader_list *next; +} reader_list; + +static void remove_finished_readers(reader_list **prev_reader, uint64_t completed) +{ + while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, completed)) + { + /* If you don't have what you're looking for now, you never + * will. Wake up and leave me alone. */ + pthread_cond_signal((*prev_reader)->data); + *prev_reader = (*prev_reader)->next; + } +} + +static int read_packet(xcb_connection_t *c) +{ + xcb_generic_reply_t genrep; + int length = 32; + int eventlength = 0; /* length after first 32 bytes for GenericEvents */ + void *buf; + pending_reply *pend = 0; + struct event_list *event; + + /* Wait for there to be enough data for us to read a whole packet */ + if(c->in.queue_len < length) + return 0; + + /* Get the response type, length, and sequence number. */ + memcpy(&genrep, c->in.queue, sizeof(genrep)); + + /* Compute 32-bit sequence number of this packet. */ + if((genrep.response_type & 0x7f) != XCB_KEYMAP_NOTIFY) + { + uint64_t lastread = c->in.request_read; + c->in.request_read = (lastread & UINT64_C(0xffffffffffff0000)) | genrep.sequence; + if(XCB_SEQUENCE_COMPARE(c->in.request_read, <, lastread)) + c->in.request_read += 0x10000; + if(XCB_SEQUENCE_COMPARE(c->in.request_read, >, c->in.request_expected)) + c->in.request_expected = c->in.request_read; + + if(c->in.request_read != lastread) + { + if(c->in.current_reply) + { + _xcb_map_put(c->in.replies, lastread, c->in.current_reply); + c->in.current_reply = 0; + c->in.current_reply_tail = &c->in.current_reply; + } + c->in.request_completed = c->in.request_read - 1; + } + + while(c->in.pending_replies && + c->in.pending_replies->workaround != WORKAROUND_EXTERNAL_SOCKET_OWNER && + XCB_SEQUENCE_COMPARE (c->in.pending_replies->last_request, <=, c->in.request_completed)) + { + pending_reply *oldpend = c->in.pending_replies; + c->in.pending_replies = oldpend->next; + if(!oldpend->next) + c->in.pending_replies_tail = &c->in.pending_replies; + free(oldpend); + } + + if(genrep.response_type == XCB_ERROR) + c->in.request_completed = c->in.request_read; + + remove_finished_readers(&c->in.readers, c->in.request_completed); + } + + if(genrep.response_type == XCB_ERROR || genrep.response_type == XCB_REPLY) + { + pend = c->in.pending_replies; + if(pend && + !(XCB_SEQUENCE_COMPARE(pend->first_request, <=, c->in.request_read) && + (pend->workaround == WORKAROUND_EXTERNAL_SOCKET_OWNER || + XCB_SEQUENCE_COMPARE(c->in.request_read, <=, pend->last_request)))) + pend = 0; + } + + /* For reply packets, check that the entire packet is available. */ + if(genrep.response_type == XCB_REPLY) + { + if(pend && pend->workaround == WORKAROUND_GLX_GET_FB_CONFIGS_BUG) + { + uint32_t *p = (uint32_t *) c->in.queue; + genrep.length = p[2] * p[3] * 2; + } + length += genrep.length * 4; + } + + /* XGE events may have sizes > 32 */ + if ((genrep.response_type & 0x7f) == XCB_XGE_EVENT) + eventlength = genrep.length * 4; + + buf = malloc(length + eventlength + + (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t))); + if(!buf) + { + _xcb_conn_shutdown(c); + return 0; + } + + if(_xcb_in_read_block(c, buf, length) <= 0) + { + free(buf); + return 0; + } + + /* pull in XGE event data if available, append after event struct */ + if (eventlength) + { + if(_xcb_in_read_block(c, &((xcb_generic_event_t*)buf)[1], eventlength) <= 0) + { + free(buf); + return 0; + } + } + + if(pend && (pend->flags & XCB_REQUEST_DISCARD_REPLY)) + { + free(buf); + return 1; + } + + if(genrep.response_type != XCB_REPLY) + ((xcb_generic_event_t *) buf)->full_sequence = c->in.request_read; + + /* reply, or checked error */ + if( genrep.response_type == XCB_REPLY || + (genrep.response_type == XCB_ERROR && pend && (pend->flags & XCB_REQUEST_CHECKED))) + { + struct reply_list *cur = malloc(sizeof(struct reply_list)); + if(!cur) + { + _xcb_conn_shutdown(c); + free(buf); + return 0; + } + cur->reply = buf; + cur->next = 0; + *c->in.current_reply_tail = cur; + c->in.current_reply_tail = &cur->next; + if(c->in.readers && c->in.readers->request == c->in.request_read) + pthread_cond_signal(c->in.readers->data); + return 1; + } + + /* event, or unchecked error */ + event = malloc(sizeof(struct event_list)); + if(!event) + { + _xcb_conn_shutdown(c); + free(buf); + return 0; + } + event->event = buf; + event->next = 0; + *c->in.events_tail = event; + c->in.events_tail = &event->next; + pthread_cond_signal(&c->in.event_cond); + return 1; /* I have something for you... */ +} + +static xcb_generic_event_t *get_event(xcb_connection_t *c) +{ + struct event_list *cur = c->in.events; + xcb_generic_event_t *ret; + if(!c->in.events) + return 0; + ret = cur->event; + c->in.events = cur->next; + if(!cur->next) + c->in.events_tail = &c->in.events; + free(cur); + return ret; +} + +static void free_reply_list(struct reply_list *head) +{ + while(head) + { + struct reply_list *cur = head; + head = cur->next; + free(cur->reply); + free(cur); + } +} + +static int read_block(const int fd, void *buf, const ssize_t len) +{ + int done = 0; + while(done < len) + { + int ret = recv(fd, ((char *) buf) + done, len - done,MSG_WAITALL); + if(ret > 0) + done += ret; +#ifndef _WIN32 + if(ret < 0 && errno == EAGAIN) +#else + if(ret == SOCKET_ERROR && WSAGetLastError() == WSAEWOULDBLOCK) +#endif /* !_Win32 */ + { +#if USE_POLL + struct pollfd pfd; + pfd.fd = fd; + pfd.events = POLLIN; + pfd.revents = 0; + do { + ret = poll(&pfd, 1, -1); + } while (ret == -1 && errno == EINTR); +#else + fd_set fds; + FD_ZERO(&fds); + FD_SET(fd, &fds); + + /* Initializing errno here makes sure that for Win32 this loop will execute only once */ + errno = 0; + do { + ret = select(fd + 1, &fds, 0, 0, 0); + } while (ret == -1 && errno == EINTR); +#endif /* USE_POLL */ + } + if(ret <= 0) + return ret; + } + return len; +} + +static int poll_for_reply(xcb_connection_t *c, uint64_t request, void **reply, xcb_generic_error_t **error) +{ + struct reply_list *head; + + /* If an error occurred when issuing the request, fail immediately. */ + if(!request) + head = 0; + /* We've read requests past the one we want, so if it has replies we have + * them all and they're in the replies map. */ + else if(XCB_SEQUENCE_COMPARE(request, <, c->in.request_read)) + { + head = _xcb_map_remove(c->in.replies, request); + if(head && head->next) + _xcb_map_put(c->in.replies, request, head->next); + } + /* We're currently processing the responses to the request we want, and we + * have a reply ready to return. So just return it without blocking. */ + else if(request == c->in.request_read && c->in.current_reply) + { + head = c->in.current_reply; + c->in.current_reply = head->next; + if(!head->next) + c->in.current_reply_tail = &c->in.current_reply; + } + /* We know this request can't have any more replies, and we've already + * established it doesn't have a reply now. Don't bother blocking. */ + else if(request == c->in.request_completed) + head = 0; + /* We may have more replies on the way for this request: block until we're + * sure. */ + else + return 0; + + if(error) + *error = 0; + *reply = 0; + + if(head) + { + if(((xcb_generic_reply_t *) head->reply)->response_type == XCB_ERROR) + { + if(error) + *error = head->reply; + else + free(head->reply); + } + else + *reply = head->reply; + + free(head); + } + + return 1; +} + +static void insert_reader(reader_list **prev_reader, reader_list *reader, uint64_t request, pthread_cond_t *cond) +{ + while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, request)) + prev_reader = &(*prev_reader)->next; + reader->request = request; + reader->data = cond; + reader->next = *prev_reader; + *prev_reader = reader; +} + +static void remove_reader(reader_list **prev_reader, reader_list *reader) +{ + while(*prev_reader && XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, reader->request)) + if(*prev_reader == reader) + { + *prev_reader = (*prev_reader)->next; + break; + } +} + +static void *wait_for_reply(xcb_connection_t *c, uint64_t request, xcb_generic_error_t **e) +{ + void *ret = 0; + + /* If this request has not been written yet, write it. */ + if(c->out.return_socket || _xcb_out_flush_to(c, request)) + { + pthread_cond_t cond = PTHREAD_COND_INITIALIZER; + reader_list reader; + + insert_reader(&c->in.readers, &reader, request, &cond); + + while(!poll_for_reply(c, request, &ret, e)) + if(!_xcb_conn_wait(c, &cond, 0, 0)) + break; + + remove_reader(&c->in.readers, &reader); + pthread_cond_destroy(&cond); + } + + _xcb_in_wake_up_next_reader(c); + return ret; +} + +static uint64_t widen(xcb_connection_t *c, unsigned int request) +{ + uint64_t widened_request = (c->out.request & UINT64_C(0xffffffff00000000)) | request; + if(widened_request > c->out.request) + widened_request -= UINT64_C(1) << 32; + return widened_request; +} + +/* Public interface */ + +void *xcb_wait_for_reply(xcb_connection_t *c, unsigned int request, xcb_generic_error_t **e) +{ + void *ret; + if(e) + *e = 0; + if(c->has_error) + return 0; + + pthread_mutex_lock(&c->iolock); + ret = wait_for_reply(c, widen(c, request), e); + pthread_mutex_unlock(&c->iolock); + return ret; +} + +static void insert_pending_discard(xcb_connection_t *c, pending_reply **prev_next, uint64_t seq) +{ + pending_reply *pend; + pend = malloc(sizeof(*pend)); + if(!pend) + { + _xcb_conn_shutdown(c); + return; + } + + pend->first_request = seq; + pend->last_request = seq; + pend->workaround = 0; + pend->flags = XCB_REQUEST_DISCARD_REPLY; + pend->next = *prev_next; + *prev_next = pend; + + if(!pend->next) + c->in.pending_replies_tail = &pend->next; +} + +static void discard_reply(xcb_connection_t *c, uint64_t request) +{ + void *reply; + pending_reply **prev_pend; + + /* Free any replies or errors that we've already read. Stop if + * xcb_wait_for_reply would block or we've run out of replies. */ + while(poll_for_reply(c, request, &reply, 0) && reply) + free(reply); + + /* If we've proven there are no more responses coming, we're done. */ + if(XCB_SEQUENCE_COMPARE(request, <=, c->in.request_completed)) + return; + + /* Walk the list of pending requests. Mark the first match for deletion. */ + for(prev_pend = &c->in.pending_replies; *prev_pend; prev_pend = &(*prev_pend)->next) + { + if(XCB_SEQUENCE_COMPARE((*prev_pend)->first_request, >, request)) + break; + + if((*prev_pend)->first_request == request) + { + /* Pending reply found. Mark for discard: */ + (*prev_pend)->flags |= XCB_REQUEST_DISCARD_REPLY; + return; + } + } + + /* Pending reply not found (likely due to _unchecked request). Create one: */ + insert_pending_discard(c, prev_pend, request); +} + +void xcb_discard_reply(xcb_connection_t *c, unsigned int sequence) +{ + if(c->has_error) + return; + + /* If an error occurred when issuing the request, fail immediately. */ + if(!sequence) + return; + + pthread_mutex_lock(&c->iolock); + discard_reply(c, widen(c, sequence)); + pthread_mutex_unlock(&c->iolock); +} + +int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error) +{ + int ret; + if(c->has_error) + { + *reply = 0; + if(error) + *error = 0; + return 1; /* would not block */ + } + assert(reply != 0); + pthread_mutex_lock(&c->iolock); + ret = poll_for_reply(c, widen(c, request), reply, error); + pthread_mutex_unlock(&c->iolock); + return ret; +} + +xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c) +{ + xcb_generic_event_t *ret; + if(c->has_error) + return 0; + pthread_mutex_lock(&c->iolock); + /* get_event returns 0 on empty list. */ + while(!(ret = get_event(c))) + if(!_xcb_conn_wait(c, &c->in.event_cond, 0, 0)) + break; + + _xcb_in_wake_up_next_reader(c); + pthread_mutex_unlock(&c->iolock); + return ret; +} + +static xcb_generic_event_t *poll_for_next_event(xcb_connection_t *c, int queued) +{ + xcb_generic_event_t *ret = 0; + if(!c->has_error) + { + pthread_mutex_lock(&c->iolock); + /* FIXME: follow X meets Z architecture changes. */ + ret = get_event(c); + if(!ret && !queued && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ + ret = get_event(c); + pthread_mutex_unlock(&c->iolock); + } + return ret; +} + +xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c) +{ + return poll_for_next_event(c, 0); +} + +xcb_generic_event_t *xcb_poll_for_queued_event(xcb_connection_t *c) +{ + return poll_for_next_event(c, 1); +} + +xcb_generic_error_t *xcb_request_check(xcb_connection_t *c, xcb_void_cookie_t cookie) +{ + uint64_t request; + xcb_generic_error_t *ret = 0; + void *reply; + if(c->has_error) + return 0; + pthread_mutex_lock(&c->iolock); + request = widen(c, cookie.sequence); + if(XCB_SEQUENCE_COMPARE(request, >=, c->in.request_expected) + && XCB_SEQUENCE_COMPARE(request, >, c->in.request_completed)) + { + _xcb_out_send_sync(c); + _xcb_out_flush_to(c, c->out.request); + } + reply = wait_for_reply(c, request, &ret); + assert(!reply); + pthread_mutex_unlock(&c->iolock); + return ret; +} + +/* Private interface */ + +int _xcb_in_init(_xcb_in *in) +{ + if(pthread_cond_init(&in->event_cond, 0)) + return 0; + in->reading = 0; + + in->queue_len = 0; + + in->request_read = 0; + in->request_completed = 0; + + in->replies = _xcb_map_new(); + if(!in->replies) + return 0; + + in->current_reply_tail = &in->current_reply; + in->events_tail = &in->events; + in->pending_replies_tail = &in->pending_replies; + + return 1; +} + +void _xcb_in_destroy(_xcb_in *in) +{ + pthread_cond_destroy(&in->event_cond); + free_reply_list(in->current_reply); + _xcb_map_delete(in->replies, (void (*)(void *)) free_reply_list); + while(in->events) + { + struct event_list *e = in->events; + in->events = e->next; + free(e->event); + free(e); + } + while(in->pending_replies) + { + pending_reply *pend = in->pending_replies; + in->pending_replies = pend->next; + free(pend); + } +} + +void _xcb_in_wake_up_next_reader(xcb_connection_t *c) +{ + int pthreadret; + if(c->in.readers) + pthreadret = pthread_cond_signal(c->in.readers->data); + else + pthreadret = pthread_cond_signal(&c->in.event_cond); + assert(pthreadret == 0); +} + +int _xcb_in_expect_reply(xcb_connection_t *c, uint64_t request, enum workarounds workaround, int flags) +{ + pending_reply *pend = malloc(sizeof(pending_reply)); + assert(workaround != WORKAROUND_NONE || flags != 0); + if(!pend) + { + _xcb_conn_shutdown(c); + return 0; + } + pend->first_request = pend->last_request = request; + pend->workaround = workaround; + pend->flags = flags; + pend->next = 0; + *c->in.pending_replies_tail = pend; + c->in.pending_replies_tail = &pend->next; + return 1; +} + +void _xcb_in_replies_done(xcb_connection_t *c) +{ + struct pending_reply *pend; + if (c->in.pending_replies_tail != &c->in.pending_replies) + { + pend = container_of(c->in.pending_replies_tail, struct pending_reply, next); + if(pend->workaround == WORKAROUND_EXTERNAL_SOCKET_OWNER) + { + pend->last_request = c->out.request; + pend->workaround = WORKAROUND_NONE; + } + } +} + +int _xcb_in_read(xcb_connection_t *c) +{ + int n = recv(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len,MSG_WAITALL); + if(n > 0) + c->in.queue_len += n; + while(read_packet(c)) + /* empty */; +#ifndef _WIN32 + if((n > 0) || (n < 0 && errno == EAGAIN)) +#else + if((n > 0) || (n < 0 && WSAGetLastError() == WSAEWOULDBLOCK)) +#endif /* !_WIN32 */ + return 1; + _xcb_conn_shutdown(c); + return 0; +} + +int _xcb_in_read_block(xcb_connection_t *c, void *buf, int len) +{ + int done = c->in.queue_len; + if(len < done) + done = len; + + memcpy(buf, c->in.queue, done); + c->in.queue_len -= done; + memmove(c->in.queue, c->in.queue + done, c->in.queue_len); + + if(len > done) + { + int ret = read_block(c->fd, (char *) buf + done, len - done); + if(ret <= 0) + { + _xcb_conn_shutdown(c); + return ret; + } + } + + return len; +} |