1 files changed, 284 insertions, 6 deletions

diff --git a/libxcb/src/xcb_in.c b/libxcb/src/xcb_in.c
index 8a7af920b..8c3a58cc3 100644
--- a/libxcb/src/xcb_in.c
+++ b/libxcb/src/xcb_in.c
@@ -60,6 +60,23 @@ struct event_list {
     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;
@@ -90,11 +107,66 @@ static void remove_finished_readers(reader_list **prev_reader, uint64_t complete
     }
 }
 
+#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;
@@ -164,13 +236,18 @@ static int read_packet(xcb_connection_t *c)
             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 +
+    bufsize = length + eventlength + nfd * sizeof(int)  +
         (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t));
     if (bufsize < INT32_MAX)
         buf = malloc((size_t) bufsize);
@@ -198,6 +275,17 @@ static int read_packet(xcb_connection_t *c)
         }
     }
 
+#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);
@@ -237,9 +325,12 @@ static int read_packet(xcb_connection_t *c)
     }
     event->event = buf;
     event->next = 0;
-    *c->in.events_tail = event;
-    c->in.events_tail = &event->next;
-    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... */
 }
 
@@ -431,6 +522,11 @@ void *xcb_wait_for_reply(xcb_connection_t *c, unsigned int request, xcb_generic_
     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;
@@ -577,6 +673,126 @@ xcb_generic_error_t *xcb_request_check(xcb_connection_t *c, xcb_void_cookie_t co
     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);
+    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);
+}
+
 /* Private interface */
 
 int _xcb_in_init(_xcb_in *in)
@@ -665,11 +881,73 @@ void _xcb_in_replies_done(xcb_connection_t *c)
 
 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, 0);
-    if(n > 0)
+    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 */;
+#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