/* 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. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include #include #include #if USE_POLL #include #endif #ifndef _WIN32 #include #include #endif #ifdef _WIN32 #include "xcb_windefs.h" #endif /* _WIN32 */ #include "xcb.h" #include "xcbext.h" #include "xcbint.h" #define XCB_ERROR 0 #define XCB_REPLY 1 #define XCB_XGE_EVENT 35 struct event_list { xcb_generic_event_t *event; struct event_list *next; }; struct xcb_special_event { struct xcb_special_event *next; /* Match XGE events for the specific extension and event ID (the * first 32 bit word after evtype) */ uint8_t extension; uint32_t eid; uint32_t *stamp; struct event_list *events; struct event_list **events_tail; pthread_cond_t special_event_cond; }; 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; typedef struct special_list { xcb_special_event_t *se; struct special_list *next; } special_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; } } #if HAVE_SENDMSG static int read_fds(xcb_connection_t *c, int *fds, int nfd) { int *ifds = &c->in.in_fd.fd[c->in.in_fd.ifd]; int infd = c->in.in_fd.nfd - c->in.in_fd.ifd; if (nfd > infd) return 0; memcpy(fds, ifds, nfd * sizeof (int)); c->in.in_fd.ifd += nfd; return 1; } #endif typedef struct xcb_ge_special_event_t { uint8_t response_type; /**< */ uint8_t extension; /**< */ uint16_t sequence; /**< */ uint32_t length; /**< */ uint16_t evtype; /**< */ uint8_t pad0[2]; /**< */ uint32_t eid; /**< */ uint8_t pad1[16]; /**< */ } xcb_ge_special_event_t; static int event_special(xcb_connection_t *c, struct event_list *event) { struct xcb_special_event *special_event; struct xcb_ge_special_event_t *ges = (void *) event->event; /* Special events are always XGE events */ if ((ges->response_type & 0x7f) != XCB_XGE_EVENT) return 0; for (special_event = c->in.special_events; special_event; special_event = special_event->next) { if (ges->extension == special_event->extension && ges->eid == special_event->eid) { *special_event->events_tail = event; special_event->events_tail = &event->next; if (special_event->stamp) ++(*special_event->stamp); pthread_cond_signal(&special_event->special_event_cond); return 1; } } return 0; } static int read_packet(xcb_connection_t *c) { xcb_generic_reply_t genrep; uint64_t length = 32; uint64_t eventlength = 0; /* length after first 32 bytes for GenericEvents */ int nfd = 0; /* Number of file descriptors attached to the reply */ uint64_t bufsize; 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; /* XXX a bit of a hack -- we "know" that all FD replys place * the number of fds in the pad0 byte */ if (pend && pend->flags & XCB_REQUEST_REPLY_FDS) nfd = genrep.pad0; } /* XGE events may have sizes > 32 */ if ((genrep.response_type & 0x7f) == XCB_XGE_EVENT) eventlength = genrep.length * 4; bufsize = length + eventlength + nfd * sizeof(int) + (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t)); if (bufsize < INT32_MAX) buf = malloc((size_t) bufsize); else buf = NULL; if(!buf) { _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 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 HAVE_SENDMSG if (nfd) { if (!read_fds(c, (int *) &((char *) buf)[length], nfd)) { free(buf); return 0; } } #endif 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, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 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, XCB_CONN_CLOSED_MEM_INSUFFICIENT); free(buf); return 0; } event->event = buf; event->next = 0; if (!event_special(c, event)) { *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, 0); 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 insert_special(special_list **prev_special, special_list *special, xcb_special_event_t *se) { special->se = se; special->next = *prev_special; *prev_special = special; } static void remove_special(special_list **prev_special, special_list *special) { while(*prev_special) { if(*prev_special == special) { *prev_special = (*prev_special)->next; break; } prev_special = &(*prev_special)->next; } } 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; } void *xcb_wait_for_reply64(xcb_connection_t *c, uint64_t 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, request, e); pthread_mutex_unlock(&c->iolock); return ret; } int *xcb_get_reply_fds(xcb_connection_t *c, void *reply, size_t reply_size) { return (int *) (&((char *) reply)[reply_size]); } 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, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 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); } void xcb_discard_reply64(xcb_connection_t *c, uint64_t 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, 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); if(!ret && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ ret = poll_for_reply(c, widen(c, request), reply, error); pthread_mutex_unlock(&c->iolock); return ret; } int xcb_poll_for_reply64(xcb_connection_t *c, uint64_t 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, request, reply, error); if(!ret && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ ret = poll_for_reply(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 && c->in.reading == 0 && _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; } static xcb_generic_event_t *get_special_event(xcb_connection_t *c, xcb_special_event_t *se) { xcb_generic_event_t *event = NULL; struct event_list *events; if ((events = se->events) != NULL) { event = events->event; if (!(se->events = events->next)) se->events_tail = &se->events; free (events); } return event; } xcb_generic_event_t *xcb_poll_for_special_event(xcb_connection_t *c, xcb_special_event_t *se) { xcb_generic_event_t *event; if(c->has_error) return 0; pthread_mutex_lock(&c->iolock); event = get_special_event(c, se); if(!event && c->in.reading == 0 && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ event = get_special_event(c, se); pthread_mutex_unlock(&c->iolock); return event; } xcb_generic_event_t *xcb_wait_for_special_event(xcb_connection_t *c, xcb_special_event_t *se) { special_list special; xcb_generic_event_t *event; if(c->has_error) return 0; pthread_mutex_lock(&c->iolock); insert_special(&c->in.special_waiters, &special, se); /* get_special_event returns 0 on empty list. */ while(!(event = get_special_event(c, se))) if(!_xcb_conn_wait(c, &se->special_event_cond, 0, 0)) break; remove_special(&c->in.special_waiters, &special); _xcb_in_wake_up_next_reader(c); pthread_mutex_unlock(&c->iolock); return event; } xcb_special_event_t * xcb_register_for_special_xge(xcb_connection_t *c, xcb_extension_t *ext, uint32_t eid, uint32_t *stamp) { xcb_special_event_t *se; const xcb_query_extension_reply_t *ext_reply; if(c->has_error) return NULL; ext_reply = xcb_get_extension_data(c, ext); if (!ext_reply) return NULL; pthread_mutex_lock(&c->iolock); for (se = c->in.special_events; se; se = se->next) { if (se->extension == ext_reply->major_opcode && se->eid == eid) { pthread_mutex_unlock(&c->iolock); return NULL; } } se = calloc(1, sizeof(xcb_special_event_t)); if (!se) { pthread_mutex_unlock(&c->iolock); return NULL; } se->extension = ext_reply->major_opcode; se->eid = eid; se->events = NULL; se->events_tail = &se->events; se->stamp = stamp; pthread_cond_init(&se->special_event_cond, 0); se->next = c->in.special_events; c->in.special_events = se; pthread_mutex_unlock(&c->iolock); return se; } void xcb_unregister_for_special_event(xcb_connection_t *c, xcb_special_event_t *se) { xcb_special_event_t *s, **prev; struct event_list *events, *next; if (!se) return; if (c->has_error) return; pthread_mutex_lock(&c->iolock); for (prev = &c->in.special_events; (s = *prev) != NULL; prev = &(s->next)) { if (s == se) { *prev = se->next; for (events = se->events; events; events = next) { next = events->next; free (events->event); free (events); } pthread_cond_destroy(&se->special_event_cond); free (se); break; } } pthread_mutex_unlock(&c->iolock); } /* 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.special_waiters) pthreadret = pthread_cond_signal(&c->in.special_waiters->se->special_event_cond); 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, XCB_CONN_CLOSED_MEM_INSUFFICIENT); 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) { if (XCB_SEQUENCE_COMPARE(pend->first_request, <=, c->out.request)) { pend->last_request = c->out.request; pend->workaround = WORKAROUND_NONE; } else { /* The socket was taken, but no requests were actually sent * so just discard the pending_reply that was created. */ struct pending_reply **prev_next = &c->in.pending_replies; while (*prev_next != pend) prev_next = &(*prev_next)->next; *prev_next = NULL; c->in.pending_replies_tail = prev_next; free(pend); } } } } int _xcb_in_read(xcb_connection_t *c) { int n; #if HAVE_SENDMSG struct iovec iov = { .iov_base = c->in.queue + c->in.queue_len, .iov_len = sizeof(c->in.queue) - c->in.queue_len, }; union { struct cmsghdr cmsghdr; char buf[CMSG_SPACE(XCB_MAX_PASS_FD * sizeof(int))]; } cmsgbuf; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, .msg_iov = &iov, .msg_iovlen = 1, .msg_control = cmsgbuf.buf, .msg_controllen = CMSG_SPACE(sizeof(int) * (XCB_MAX_PASS_FD - c->in.in_fd.nfd)), }; n = recvmsg(c->fd, &msg, 0); /* Check for truncation errors. Only MSG_CTRUNC is * probably possible here, which would indicate that * the sender tried to transmit more than XCB_MAX_PASS_FD * file descriptors. */ if (msg.msg_flags & (MSG_TRUNC|MSG_CTRUNC)) { _xcb_conn_shutdown(c, XCB_CONN_CLOSED_FDPASSING_FAILED); return 0; } #else n = recv(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len, 0); #endif if(n > 0) { #if HAVE_SENDMSG struct cmsghdr *hdr; if (msg.msg_controllen >= sizeof (struct cmsghdr)) { for (hdr = CMSG_FIRSTHDR(&msg); hdr; hdr = CMSG_NXTHDR(&msg, hdr)) { if (hdr->cmsg_level == SOL_SOCKET && hdr->cmsg_type == SCM_RIGHTS) { int nfd = (hdr->cmsg_len - CMSG_LEN(0)) / sizeof (int); memcpy(&c->in.in_fd.fd[c->in.in_fd.nfd], CMSG_DATA(hdr), nfd * sizeof (int)); c->in.in_fd.nfd += nfd; } } } #endif c->in.queue_len += n; } while(read_packet(c)) /* empty */; #if HAVE_SENDMSG if (c->in.in_fd.nfd) { c->in.in_fd.nfd -= c->in.in_fd.ifd; memmove(&c->in.in_fd.fd[0], &c->in.in_fd.fd[c->in.in_fd.ifd], c->in.in_fd.nfd * sizeof (int)); c->in.in_fd.ifd = 0; /* If we have any left-over file descriptors after emptying * the input buffer, then the server sent some that we weren't * expecting. Close them and mark the connection as broken; */ if (c->in.queue_len == 0 && c->in.in_fd.nfd != 0) { int i; for (i = 0; i < c->in.in_fd.nfd; i++) close(c->in.in_fd.fd[i]); _xcb_conn_shutdown(c, XCB_CONN_CLOSED_FDPASSING_FAILED); return 0; } } #endif #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, XCB_CONN_ERROR); 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, XCB_CONN_ERROR); return ret; } } return len; }