X-Git-Url: http://git.demorecorder.com/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fxcb_in.c;h=8c3a58cc3fb5e24d3a6d9f560dbefb14156f3ec5;hb=83f28ef8655acff746eab64eabe2e31f8cf0c892;hp=e050dfc817603d6bcd2779773d6c5027a6cc2cd5;hpb=7875040fa179d8ca3fa4ec046c1b8c2a351a6621;p=free-sw%2Fxcb%2Flibxcb

diff --git a/src/xcb_in.c b/src/xcb_in.c
index e050dfc..8c3a58c 100644
--- a/src/xcb_in.c
+++ b/src/xcb_in.c
@@ -25,6 +25,10 @@
 
 /* Stuff that reads stuff from the server. */
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #include <assert.h>
 #include <string.h>
 #include <stdlib.h>
@@ -35,46 +39,138 @@
 #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
+
+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 {
-    unsigned int request;
+    uint64_t first_request;
+    uint64_t last_request;
     enum workarounds workaround;
+    int flags;
     struct pending_reply *next;
 } pending_reply;
 
-typedef struct XCBReplyData {
-    unsigned int request;
-    void *data;
-    XCBGenericError **error;
-} XCBReplyData;
+typedef struct reader_list {
+    uint64_t request;
+    pthread_cond_t *data;
+    struct reader_list *next;
+} reader_list;
 
-static int match_request_error(const void *request, const void *data)
+static void remove_finished_readers(reader_list **prev_reader, uint64_t completed)
 {
-    const XCBGenericError *e = data;
-    return e->response_type == 0 && e->sequence == ((*(unsigned int *) request) & 0xffff);
+    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 match_reply(const void *request, const void *data)
+#if HAVE_SENDMSG
+static int read_fds(xcb_connection_t *c, int *fds, int nfd)
 {
-    return ((XCBReplyData *) data)->request == *(unsigned int *) request;
-}
+    int *ifds = &c->in.in_fd.fd[c->in.in_fd.ifd];
+    int infd = c->in.in_fd.nfd - c->in.in_fd.ifd;
 
-static void wake_up_next_reader(XCBConnection *c)
+    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)
 {
-    XCBReplyData *cur = _xcb_list_peek_head(c->in.readers);
-    int pthreadret;
-    if(cur)
-        pthreadret = pthread_cond_signal(cur->data);
-    else
-        pthreadret = pthread_cond_signal(&c->in.event_cond);
-    assert(pthreadret == 0);
+    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(XCBConnection *c)
+static int read_packet(xcb_connection_t *c)
 {
-    XCBGenericRep genrep;
-    int length = 32;
-    unsigned char *buf;
+    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)
@@ -84,93 +180,218 @@ static int read_packet(XCBConnection *c)
     memcpy(&genrep, c->in.queue, sizeof(genrep));
 
     /* Compute 32-bit sequence number of this packet. */
-    if((genrep.response_type & 0x7f) != KeymapNotify)
+    if((genrep.response_type & 0x7f) != XCB_KEYMAP_NOTIFY)
     {
-        int lastread = c->in.request_read;
-        c->in.request_read = (lastread & 0xffff0000) | genrep.sequence;
-        if(c->in.request_read != lastread && !_xcb_queue_is_empty(c->in.current_reply))
+        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))
         {
-            _xcb_map_put(c->in.replies, lastread, c->in.current_reply);
-            c->in.current_reply = _xcb_queue_new();
+            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(c->in.request_read < lastread)
-            c->in.request_read += 0x10000;
+
+        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 == 1)
+    if(genrep.response_type == XCB_REPLY)
     {
-        pending_reply *pend = c->in.pending_replies;
-        if(pend && pend->request == c->in.request_read)
+        if(pend && pend->workaround == WORKAROUND_GLX_GET_FB_CONFIGS_BUG)
         {
-            switch(pend->workaround)
-            {
-            case WORKAROUND_NONE:
-                break;
-            case WORKAROUND_GLX_GET_FB_CONFIGS_BUG:
-                {
-                    CARD32 *p = (CARD32 *) c->in.queue;
-                    genrep.length = p[2] * p[3] * 2;
-                }
-                break;
-            }
-            c->in.pending_replies = pend->next;
-            if(!pend->next)
-                c->in.pending_replies_tail = &c->in.pending_replies;
-            free(pend);
+            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;
     }
 
-    buf = malloc(length);
+    /* 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;
     }
 
-    if(buf[0] == 1) /* response is a reply */
+    /* 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)
     {
-        XCBReplyData *reader = _xcb_list_find(c->in.readers, match_reply, &c->in.request_read);
-        _xcb_queue_enqueue(c->in.current_reply, buf);
-        if(reader)
-            pthread_cond_signal(reader->data);
+        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(buf[0] == 0) /* response is an error */
+    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)))
     {
-        XCBReplyData *reader = _xcb_list_find(c->in.readers, match_reply, &c->in.request_read);
-        if(reader && reader->error)
+        struct reply_list *cur = malloc(sizeof(struct reply_list));
+        if(!cur)
         {
-            *reader->error = (XCBGenericError *) buf;
-            pthread_cond_signal(reader->data);
-            return 1;
+            _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;
 
-    /* event, or error without a waiting reader */
-    _xcb_queue_enqueue(c->in.events, buf);
-    pthread_cond_signal(&c->in.event_cond);
+    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 int read_block(const int fd, void *buf, const size_t len)
+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 = read(fd, ((char *) buf) + done, len - done);
+        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);
-            ret = select(fd + 1, &fds, 0, 0, 0);
+
+	    /* 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;
@@ -178,115 +399,398 @@ static int read_block(const int fd, void *buf, const size_t len)
     return len;
 }
 
-/* Public interface */
+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;
 
-void *XCBWaitForReply(XCBConnection *c, unsigned int request, XCBGenericError **e)
+    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)
 {
-    pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
-    XCBReplyData reader;
     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;
+}
 
-    /* If this request has not been written yet, write it. */
-    if((signed int) (c->out.request_written - request) < 0)
-        if(!_xcb_out_flush(c))
-            goto done; /* error */
-
-    if(_xcb_list_find(c->in.readers, match_reply, &request))
-        goto done; /* error */
+int *xcb_get_reply_fds(xcb_connection_t *c, void *reply, size_t reply_size)
+{
+    return (int *) (&((char *) reply)[reply_size]);
+}
 
-    if(e)
+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)
     {
-        *e = _xcb_list_remove(c->in.events, match_request_error, &request);
-        if(*e)
-            goto done;
+        _xcb_conn_shutdown(c, XCB_CONN_CLOSED_MEM_INSUFFICIENT);
+        return;
     }
 
-    reader.request = request;
-    reader.data = &cond;
-    reader.error = e;
-    _xcb_list_append(c->in.readers, &reader);
+    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 this request has not been read yet, wait for it. */
-    while(!(e && *e) && ((signed int) (c->in.request_read - request) < 0 ||
-            (c->in.request_read == request &&
-	     _xcb_queue_is_empty(c->in.current_reply))))
-        if(!_xcb_conn_wait(c, /*should_write*/ 0, &cond))
-            goto done;
+    /* If we've proven there are no more responses coming, we're done. */
+    if(XCB_SEQUENCE_COMPARE(request, <=, c->in.request_completed))
+        return;
 
-    if(c->in.request_read != request)
+    /* 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)
     {
-        _xcb_queue *q = _xcb_map_get(c->in.replies, request);
-        if(q)
+        if(XCB_SEQUENCE_COMPARE((*prev_pend)->first_request, >, request))
+            break;
+
+        if((*prev_pend)->first_request == request)
         {
-            ret = _xcb_queue_dequeue(q);
-            if(_xcb_queue_is_empty(q))
-                _xcb_queue_delete(_xcb_map_remove(c->in.replies, request), free);
+            /* Pending reply found. Mark for discard: */
+            (*prev_pend)->flags |= XCB_REQUEST_DISCARD_REPLY;
+            return;
         }
     }
-    else
-        ret = _xcb_queue_dequeue(c->in.current_reply);
 
-done:
-    _xcb_list_remove(c->in.readers, match_reply, &request);
-    pthread_cond_destroy(&cond);
+    /* 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;
 
-    wake_up_next_reader(c);
+    pthread_mutex_lock(&c->iolock);
+    discard_reply(c, widen(c, sequence));
     pthread_mutex_unlock(&c->iolock);
-    return ret;
 }
 
-XCBGenericEvent *XCBWaitEvent(XCBConnection *c)
+int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error)
 {
-    return XCBWaitForEvent(c);
+    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;
 }
 
-XCBGenericEvent *XCBWaitForEvent(XCBConnection *c)
+xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c)
 {
-    XCBGenericEvent *ret;
+    xcb_generic_event_t *ret;
+    if(c->has_error)
+        return 0;
     pthread_mutex_lock(&c->iolock);
-    /* _xcb_list_remove_head returns 0 on empty list. */
-    while(!(ret = _xcb_queue_dequeue(c->in.events)))
-        if(!_xcb_conn_wait(c, /*should_write*/ 0, &c->in.event_cond))
+    /* get_event returns 0 on empty list. */
+    while(!(ret = get_event(c)))
+        if(!_xcb_conn_wait(c, &c->in.event_cond, 0, 0))
             break;
 
-    wake_up_next_reader(c);
+    _xcb_in_wake_up_next_reader(c);
     pthread_mutex_unlock(&c->iolock);
     return ret;
 }
 
-XCBGenericEvent *XCBPollForEvent(XCBConnection *c, int *error)
+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)
 {
-    XCBGenericEvent *ret = 0;
+    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);
-    if(error)
-        *error = 0;
-    /* FIXME: follow X meets Z architecture changes. */
-    if(_xcb_in_read(c))
-        ret = _xcb_queue_dequeue(c->in.events);
-    else if(error)
-        *error = -1;
-    else
+    request = widen(c, cookie.sequence);
+    if(XCB_SEQUENCE_COMPARE(request, >=, c->in.request_expected)
+       && XCB_SEQUENCE_COMPARE(request, >, c->in.request_completed))
     {
-        fprintf(stderr, "XCBPollForEvent: I/O error occured, but no handler provided.\n");
-        abort();
+        _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;
 }
 
-unsigned int XCBGetRequestRead(XCBConnection *c)
+static xcb_generic_event_t *get_special_event(xcb_connection_t *c,
+                                              xcb_special_event_t *se)
 {
-    unsigned int ret;
+    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);
-    /* FIXME: follow X meets Z architecture changes. */
-    _xcb_in_read(c);
-    ret = c->in.request_read;
+    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)
+{
+    xcb_generic_event_t *event;
+
+    if(c->has_error)
+        return 0;
+    pthread_mutex_lock(&c->iolock);
+
+    /* 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;
+
+    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);
-    return ret;
 }
 
 /* Private interface */
@@ -300,14 +804,14 @@ int _xcb_in_init(_xcb_in *in)
     in->queue_len = 0;
 
     in->request_read = 0;
-    in->current_reply = _xcb_queue_new();
+    in->request_completed = 0;
 
     in->replies = _xcb_map_new();
-    in->events = _xcb_queue_new();
-    in->readers = _xcb_list_new();
-    if(!in->current_reply || !in->replies || !in->events || !in->readers)
+    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;
@@ -316,10 +820,15 @@ int _xcb_in_init(_xcb_in *in)
 void _xcb_in_destroy(_xcb_in *in)
 {
     pthread_cond_destroy(&in->event_cond);
-    _xcb_queue_delete(in->current_reply, free);
-    _xcb_map_delete(in->replies, free);
-    _xcb_queue_delete(in->events, free);
-    _xcb_list_delete(in->readers, 0);
+    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;
@@ -328,33 +837,128 @@ void _xcb_in_destroy(_xcb_in *in)
     }
 }
 
-int _xcb_in_expect_reply(XCBConnection *c, unsigned int request, enum workarounds workaround)
+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)
 {
-    if(workaround != WORKAROUND_NONE)
+    pending_reply *pend = malloc(sizeof(pending_reply));
+    assert(workaround != WORKAROUND_NONE || flags != 0);
+    if(!pend)
     {
-        pending_reply *pend = malloc(sizeof(pending_reply));
-        if(!pend)
-            return 0;
-        pend->request = request;
-        pend->workaround = workaround;
-        pend->next = 0;
-        *c->in.pending_replies_tail = pend;
-        c->in.pending_replies_tail = &pend->next;
+        _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;
 }
 
-int _xcb_in_read(XCBConnection *c)
+void _xcb_in_replies_done(xcb_connection_t *c)
 {
-    int n = read(c->fd, c->in.queue + c->in.queue_len, sizeof(c->in.queue) - c->in.queue_len);
-    if(n > 0)
+    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;
+
+#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,
+    };
+    char cmsgbuf[CMSG_SPACE(sizeof(int) * XCB_MAX_PASS_FD)];
+    struct msghdr msg = {
+        .msg_name = NULL,
+        .msg_namelen = 0,
+        .msg_iov = &iov,
+        .msg_iovlen = 1,
+        .msg_control = cmsgbuf,
+        .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;
+
+        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 */;
-    return (n > 0) || (n < 0 && errno == EAGAIN);
+#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(XCBConnection *c, void *buf, int len)
+int _xcb_in_read_block(xcb_connection_t *c, void *buf, int len)
 {
     int done = c->in.queue_len;
     if(len < done)
@@ -368,7 +972,10 @@ int _xcb_in_read_block(XCBConnection *c, void *buf, int len)
     {
         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;