fix for Xlib 32-bit request number issues

Make use of the new 64-bit sequence number API in XCB 1.11.1 to avoid
the 32-bit sequence number wrap in libX11.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=71338
Signed-off-by: Christian Linhart <chris@demorecorder.com>
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>

13 files changed, 219 insertions, 86 deletions

diff --git a/configure.ac b/configure.ac
index 92b791c2..14ad5430 100644
--- a/configure.ac
+++ b/configure.ac
@@ -68,8 +68,8 @@ AC_SUBST(LDFLAGS_FOR_BUILD)
 # Checks for pkg-config packages
 
 # Always required
-X11_REQUIRES='xproto >= 7.0.17 xextproto xtrans xcb >= 1.1.92'
-X11_EXTRA_DEPS="xcb >= 1.1.92"
+X11_REQUIRES='xproto >= 7.0.17 xextproto xtrans xcb >= 1.11.1'
+X11_EXTRA_DEPS="xcb >= 1.11.1"
 
 PKG_PROG_PKG_CONFIG()
 
diff --git a/include/X11/Xlibint.h b/include/X11/Xlibint.h
index 44315596..d2563d66 100644
--- a/include/X11/Xlibint.h
+++ b/include/X11/Xlibint.h
@@ -38,6 +38,7 @@ from The Open Group.
  *	Warning, there be dragons here....
  */
 
+#include <stdint.h>
 #include <X11/Xlib.h>
 #include <X11/Xproto.h>		/* to declare xEvent */
 #include <X11/XlibConf.h>	/* for configured options like XTHREADS */
@@ -205,10 +206,122 @@ struct _XDisplay
 		XGenericEventCookie *	/* in */,
 		XGenericEventCookie *   /* out*/);
 	void *cookiejar;  /* cookie events returned but not claimed */
+#ifndef LONG64
+	unsigned long last_request_read_upper32bit;
+	unsigned long request_upper32bit;
+#endif
 };
 
 #define XAllocIDs(dpy,ids,n) (*(dpy)->idlist_alloc)(dpy,ids,n)
 
+/*
+ * access "last_request_read" and "request" with 64bit
+ * warning: the value argument of the SET-macros must not
+ * have any side-effects because it may get called twice.
+ */
+#ifndef LONG64
+/* accessors for 32-bit unsigned long */
+
+#define X_DPY_GET_REQUEST(dpy) \
+    ( \
+        ((uint64_t)(((struct _XDisplay*)dpy)->request)) \
+	+ (((uint64_t)(((struct _XDisplay*)dpy)->request_upper32bit)) << 32) \
+    )
+
+#define X_DPY_SET_REQUEST(dpy, value) \
+    ( \
+        (((struct _XDisplay*)dpy)->request = \
+            (value) & 0xFFFFFFFFUL), \
+        (((struct _XDisplay*)dpy)->request_upper32bit = \
+            ((uint64_t)(value)) >> 32), \
+	(void)0 /* don't use the result */ \
+    )
+
+#define X_DPY_GET_LAST_REQUEST_READ(dpy) \
+    ( \
+        ((uint64_t)(((struct _XDisplay*)dpy)->last_request_read)) \
+        + ( \
+            ((uint64_t)( \
+                ((struct _XDisplay*)dpy)->last_request_read_upper32bit \
+            )) << 32 \
+        ) \
+    )
+
+#define X_DPY_SET_LAST_REQUEST_READ(dpy, value) \
+    ( \
+        (((struct _XDisplay*)dpy)->last_request_read = \
+            (value) & 0xFFFFFFFFUL), \
+        (((struct _XDisplay*)dpy)->last_request_read_upper32bit = \
+            ((uint64_t)(value)) >> 32), \
+	(void)0 /* don't use the result */ \
+    )
+
+/*
+ * widen a 32-bit sequence number to a 64 sequence number.
+ * This macro makes the following assumptions:
+ * - ulseq refers to a sequence that has already been sent
+ * - ulseq means the most recent possible sequence number
+ *   with these lower 32 bits.
+ *
+ * The following optimization is used:
+ * The comparison result is taken a 0 or 1 to avoid a branch.
+ */
+#define X_DPY_WIDEN_UNSIGNED_LONG_SEQ(dpy, ulseq) \
+    ( \
+        ((uint64_t)ulseq) \
+        + \
+        (( \
+            ((uint64_t)(((struct _XDisplay*)dpy)->request_upper32bit)) \
+            - (uint64_t)( \
+                (ulseq) > (((struct _XDisplay*)dpy)->request) \
+	    ) \
+        ) << 32) \
+    )
+
+#define X_DPY_REQUEST_INCREMENT(dpy) \
+    ( \
+        ((struct _XDisplay*)dpy)->request++, \
+        ( \
+            (((struct _XDisplay*)dpy)->request == 0) ? ( \
+                ((struct _XDisplay*)dpy)->request_upper32bit++ \
+	    ) : 0 \
+        ), \
+	(void)0 /* don't use the result */ \
+    )
+
+
+#define X_DPY_REQUEST_DECREMENT(dpy) \
+    ( \
+	( \
+            (((struct _XDisplay*)dpy)->request == 0) ? (\
+                ((struct _XDisplay*)dpy)->request--, /* wrap */ \
+                ((struct _XDisplay*)dpy)->request_upper32bit-- \
+            ) : ( \
+                ((struct _XDisplay*)dpy)->request-- \
+            ) \
+	), \
+	(void)0 /* don't use the result */ \
+    )
+
+#else
+/* accessors for 64-bit unsigned long */
+#define X_DPY_GET_REQUEST(dpy) \
+    (((struct _XDisplay*)dpy)->request)
+#define X_DPY_SET_REQUEST(dpy, value) \
+    ((struct _XDisplay*)dpy)->request = (value)
+
+#define X_DPY_GET_LAST_REQUEST_READ(dpy) \
+    (((struct _XDisplay*)dpy)->last_request_read)
+#define X_DPY_SET_LAST_REQUEST_READ(dpy, value) \
+    ((struct _XDisplay*)dpy)->last_request_read = (value)
+
+#define X_DPY_WIDEN_UNSIGNED_LONG_SEQ(dpy, ulseq) ulseq
+
+#define X_DPY_REQUEST_INCREMENT(dpy) ((struct _XDisplay*)dpy)->request++
+#define X_DPY_REQUEST_DECREMENT(dpy) ((struct _XDisplay*)dpy)->request--
+#endif
+
+
 #ifndef _XEVENT_
 /*
  * _QEvent datatype for use in input queueing.
@@ -673,6 +786,11 @@ typedef struct _XInternalAsync {
     XPointer data;
 } _XAsyncHandler;
 
+/*
+ * This struct is part of the ABI and is defined by value
+ * in user-code. This means that we cannot make
+ * the sequence-numbers 64bit.
+ */
 typedef struct _XAsyncEState {
     unsigned long min_sequence_number;
     unsigned long max_sequence_number;
diff --git a/src/ClDisplay.c b/src/ClDisplay.c
index bddd7736..aa904e51 100644
--- a/src/ClDisplay.c
+++ b/src/ClDisplay.c
@@ -65,7 +65,7 @@ XCloseDisplay (
 		    (*ext->close_display)(dpy, &ext->codes);
 	    }
 	    /* if the closes generated more protocol, sync them up */
-	    if (dpy->request != dpy->last_request_read)
+	    if (X_DPY_GET_REQUEST(dpy) != X_DPY_GET_LAST_REQUEST_READ(dpy))
 		XSync(dpy, 1);
 	}
 	xcb_disconnect(dpy->xcb->connection);
diff --git a/src/Font.c b/src/Font.c
index 650bc6f6..a73f9b19 100644
--- a/src/Font.c
+++ b/src/Font.c
@@ -105,7 +105,7 @@ XFontStruct *XLoadQueryFont(
       return font_result;
     LockDisplay(dpy);
     GetReq(OpenFont, req);
-    seq = dpy->request;
+    seq = dpy->request; /* Can't use extended sequence number here */
     nbytes = req->nbytes  = name ? strlen(name) : 0;
     req->fid = fid = XAllocID(dpy);
     req->length += (nbytes+3)>>2;
diff --git a/src/GetAtomNm.c b/src/GetAtomNm.c
index 32de50d2..d7f06e36 100644
--- a/src/GetAtomNm.c
+++ b/src/GetAtomNm.c
@@ -87,8 +87,8 @@ char *XGetAtomName(
 }
 
 typedef struct {
-    unsigned long start_seq;
-    unsigned long stop_seq;
+    uint64_t start_seq;
+    uint64_t stop_seq;
     Atom *atoms;
     char **names;
     int idx;
@@ -107,10 +107,11 @@ Bool _XGetAtomNameHandler(
     register _XGetAtomNameState *state;
     xGetAtomNameReply replbuf;
     register xGetAtomNameReply *repl;
+    uint64_t last_request_read = X_DPY_GET_LAST_REQUEST_READ(dpy);
 
     state = (_XGetAtomNameState *)data;
-    if (dpy->last_request_read < state->start_seq ||
-	dpy->last_request_read > state->stop_seq)
+    if (last_request_read < state->start_seq ||
+	last_request_read > state->stop_seq)
 	return False;
     while (state->idx < state->count && state->names[state->idx])
 	state->idx++;
@@ -152,7 +153,7 @@ XGetAtomNames (
     int missed = -1;
 
     LockDisplay(dpy);
-    async_state.start_seq = dpy->request + 1;
+    async_state.start_seq = X_DPY_GET_REQUEST(dpy) + 1;
     async_state.atoms = atoms;
     async_state.names = names_return;
     async_state.idx = 0;
@@ -165,7 +166,7 @@ XGetAtomNames (
     for (i = 0; i < count; i++) {
 	if (!(names_return[i] = _XGetAtomName(dpy, atoms[i]))) {
 	    missed = i;
-	    async_state.stop_seq = dpy->request;
+	    async_state.stop_seq = X_DPY_GET_REQUEST(dpy);
 	}
     }
     if (missed >= 0) {
diff --git a/src/GetWAttrs.c b/src/GetWAttrs.c
index c10824cf..0f5f7bb8 100644
--- a/src/GetWAttrs.c
+++ b/src/GetWAttrs.c
@@ -30,8 +30,8 @@ in this Software without prior written authorization from The Open Group.
 #include "Xlibint.h"
 
 typedef struct _WAttrsState {
-    unsigned long attr_seq;
-    unsigned long geom_seq;
+    uint64_t attr_seq;
+    uint64_t geom_seq;
     XWindowAttributes *attr;
 } _XWAttrsState;
 
@@ -47,10 +47,11 @@ _XWAttrsHandler(
     xGetWindowAttributesReply replbuf;
     register xGetWindowAttributesReply *repl;
     register XWindowAttributes *attr;
+    uint64_t last_request_read = X_DPY_GET_LAST_REQUEST_READ(dpy);
 
     state = (_XWAttrsState *)data;
-    if (dpy->last_request_read != state->attr_seq) {
-	if (dpy->last_request_read == state->geom_seq &&
+    if (last_request_read != state->attr_seq) {
+	if (last_request_read == state->geom_seq &&
 	    !state->attr &&
 	    rep->generic.type == X_Error &&
 	    rep->error.errorCode == BadDrawable)
@@ -99,7 +100,7 @@ _XGetWindowAttributes(
 
     GetResReq(GetWindowAttributes, w, req);
 
-    async_state.attr_seq = dpy->request;
+    async_state.attr_seq = X_DPY_GET_REQUEST(dpy);
     async_state.geom_seq = 0;
     async_state.attr = attr;
     async.next = dpy->async_handlers;
@@ -109,7 +110,7 @@ _XGetWindowAttributes(
 
     GetResReq(GetGeometry, w, req);
 
-    async_state.geom_seq = dpy->request;
+    async_state.geom_seq = X_DPY_GET_REQUEST(dpy);
 
     if (!_XReply (dpy, (xReply *)&rep, 0, xTrue)) {
 	DeqAsyncHandler(dpy, &async);
diff --git a/src/IntAtom.c b/src/IntAtom.c
index 3042b65d..d9c6c588 100644
--- a/src/IntAtom.c
+++ b/src/IntAtom.c
@@ -188,8 +188,8 @@ XInternAtom (
 }
 
 typedef struct {
-    unsigned long start_seq;
-    unsigned long stop_seq;
+    uint64_t start_seq;
+    uint64_t stop_seq;
     char **names;
     Atom *atoms;
     int count;
@@ -208,10 +208,12 @@ Bool _XIntAtomHandler(
     register int i, idx = 0;
     xInternAtomReply replbuf;
     register xInternAtomReply *repl;
+    uint64_t last_request_read = X_DPY_GET_LAST_REQUEST_READ(dpy);
 
     state = (_XIntAtomState *)data;
-    if (dpy->last_request_read < state->start_seq ||
-	dpy->last_request_read > state->stop_seq)
+
+    if (last_request_read < state->start_seq ||
+	last_request_read > state->stop_seq)
 	return False;
     for (i = 0; i < state->count; i++) {
 	if (state->atoms[i] & 0x80000000) {
@@ -252,7 +254,7 @@ XInternAtoms (
     xInternAtomReply rep;
 
     LockDisplay(dpy);
-    async_state.start_seq = dpy->request + 1;
+    async_state.start_seq = X_DPY_GET_REQUEST(dpy) + 1;
     async_state.atoms = atoms_return;
     async_state.names = names;
     async_state.count = count - 1;
@@ -266,7 +268,7 @@ XInternAtoms (
 					     &sig, &idx, &n))) {
 	    missed = i;
 	    atoms_return[i] = ~((Atom)idx);
-	    async_state.stop_seq = dpy->request;
+	    async_state.stop_seq = X_DPY_GET_REQUEST(dpy);
 	}
     }
     if (missed >= 0) {
diff --git a/src/OpenDis.c b/src/OpenDis.c
index 636860e2..82723578 100644
--- a/src/OpenDis.c
+++ b/src/OpenDis.c
@@ -197,8 +197,8 @@ XOpenDisplay (
 	dpy->idlist_alloc = _XAllocIDs;
 	dpy->synchandler = NULL;
 	dpy->savedsynchandler = NULL;
-	dpy->request = 0;
-	dpy->last_request_read = 0;
+	X_DPY_SET_REQUEST(dpy, 0);
+	X_DPY_SET_LAST_REQUEST_READ(dpy, 0);
 	dpy->default_screen = iscreen;  /* Value returned by ConnectDisplay */
 	dpy->last_req = (char *)&_dummy_request;
 
diff --git a/src/PutImage.c b/src/PutImage.c
index de085bcd..13cbba35 100644
--- a/src/PutImage.c
+++ b/src/PutImage.c
@@ -602,7 +602,7 @@ static int const HalfOrderWord[12] = {
 
 #define UnGetReq(name)\
     dpy->bufptr -= SIZEOF(x##name##Req);\
-    dpy->request--
+    X_DPY_REQUEST_DECREMENT(dpy)
 
 static void
 SendXYImage(
diff --git a/src/XlibAsync.c b/src/XlibAsync.c
index eb2b8196..d62000e5 100644
--- a/src/XlibAsync.c
+++ b/src/XlibAsync.c
@@ -32,6 +32,18 @@ from The Open Group.
 #include <X11/Xlibint.h>
 #include <X11/Xos.h>
 
+/*
+ * Xlib's _XAsyncErrorState sequence number may wrap in 32bit
+ * and we cannot use 64bit as it's public API.
+ */
+#ifdef LONG64
+#define _XLIB_ASYNC_SEQUENCE_CMP(a,op,b)     ((a == 0) || (a op b))
+#else /* !LONG64 */
+#define _XLIB_ASYNC_SEQUENCE_CMP(a,op,b)     ((a == 0) || \
+                                              (((a op b) && (b - a op (UINT32_MAX >> 1))) || \
+                                               ((b op a) && ((UINT32_MAX >> 1) op a - b))))
+#endif /* !LONG64 */
+
 /*ARGSUSED*/
 Bool
 _XAsyncErrorHandler(
@@ -51,10 +63,8 @@ _XAsyncErrorHandler(
 	 rep->error.majorCode == state->major_opcode) &&
 	(!state->minor_opcode ||
 	 rep->error.minorCode == state->minor_opcode) &&
-	(!state->min_sequence_number ||
-	 (state->min_sequence_number <= dpy->last_request_read)) &&
-	(!state->max_sequence_number ||
-	 (state->max_sequence_number >= dpy->last_request_read))) {
+	(_XLIB_ASYNC_SEQUENCE_CMP(state->min_sequence_number,<=,dpy->last_request_read)) &&
+	(_XLIB_ASYNC_SEQUENCE_CMP(state->max_sequence_number,>=,dpy->last_request_read))) {
 	state->last_error_received = rep->error.errorCode;
 	state->error_count++;
 	return True;
diff --git a/src/XlibInt.c b/src/XlibInt.c
index bbc5c826..72969488 100644
--- a/src/XlibInt.c
+++ b/src/XlibInt.c
@@ -167,8 +167,12 @@ void _XPollfdCacheDel(
 
 static int sync_hazard(Display *dpy)
 {
-    unsigned long span = dpy->request - dpy->last_request_read;
-    unsigned long hazard = min((dpy->bufmax - dpy->buffer) / SIZEOF(xReq), 65535 - 10);
+    /*
+     * "span" and "hazard" need to be signed such that the ">=" comparision
+     * works correctly in the case that hazard is greater than 65525
+     */
+    int64_t span = X_DPY_GET_REQUEST(dpy) - X_DPY_GET_LAST_REQUEST_READ(dpy);
+    int64_t hazard = min((dpy->bufmax - dpy->buffer) / SIZEOF(xReq), 65535 - 10);
     return span >= 65535 - hazard - 10;
 }
 
@@ -194,7 +198,7 @@ void _XSeqSyncFunction(
     xGetInputFocusReply rep;
     register xReq *req;
 
-    if ((dpy->request - dpy->last_request_read) >= (65535 - BUFSIZE/SIZEOF(xReq))) {
+    if ((X_DPY_GET_REQUEST(dpy) - X_DPY_GET_LAST_REQUEST_READ(dpy)) >= (65535 - BUFSIZE/SIZEOF(xReq))) {
 	GetEmptyReq(GetInputFocus, req);
 	(void) _XReply (dpy, (xReply *)&rep, 0, xTrue);
 	sync_while_locked(dpy);
@@ -276,9 +280,9 @@ _XSetLastRequestRead(
     register Display *dpy,
     register xGenericReply *rep)
 {
-    register unsigned long	newseq, lastseq;
+    register uint64_t	newseq, lastseq;
 
-    lastseq = dpy->last_request_read;
+    lastseq = X_DPY_GET_LAST_REQUEST_READ(dpy);
     /*
      * KeymapNotify has no sequence number, but is always guaranteed
      * to immediately follow another event, except when generated via
@@ -287,20 +291,21 @@ _XSetLastRequestRead(
     if ((rep->type & 0x7f) == KeymapNotify)
 	return(lastseq);
 
-    newseq = (lastseq & ~((unsigned long)0xffff)) | rep->sequenceNumber;
+    newseq = (lastseq & ~((uint64_t)0xffff)) | rep->sequenceNumber;
 
     if (newseq < lastseq) {
 	newseq += 0x10000;
-	if (newseq > dpy->request) {
+	if (newseq > X_DPY_GET_REQUEST(dpy)) {
 	    (void) fprintf (stderr,
-	    "Xlib: sequence lost (0x%lx > 0x%lx) in reply type 0x%x!\n",
-			    newseq, dpy->request,
+	    "Xlib: sequence lost (0x%llx > 0x%llx) in reply type 0x%x!\n",
+			    (unsigned long long)newseq,
+			    (unsigned long long)(X_DPY_GET_REQUEST(dpy)),
 			    (unsigned int) rep->type);
 	    newseq -= 0x10000;
 	}
     }
 
-    dpy->last_request_read = newseq;
+    X_DPY_SET_LAST_REQUEST_READ(dpy, newseq);
     return(newseq);
 }
 
@@ -1363,10 +1368,10 @@ static int _XPrintDefaultError(
 			  mesg, BUFSIZ);
     fputs("  ", fp);
     (void) fprintf(fp, mesg, event->serial);
-    XGetErrorDatabaseText(dpy, mtype, "CurrentSerial", "Current Serial #%d",
+    XGetErrorDatabaseText(dpy, mtype, "CurrentSerial", "Current Serial #%lld",
 			  mesg, BUFSIZ);
     fputs("\n  ", fp);
-    (void) fprintf(fp, mesg, dpy->request);
+    (void) fprintf(fp, mesg, (unsigned long long)(X_DPY_GET_REQUEST(dpy)));
     fputs("\n", fp);
     if (event->error_code == BadImplementation) return 0;
     return 1;
@@ -1720,7 +1725,7 @@ void *_XGetRequest(Display *dpy, CARD8 type, size_t len)
     req->reqType = type;
     req->length = len / 4;
     dpy->bufptr += len;
-    dpy->request++;
+    X_DPY_REQUEST_INCREMENT(dpy);
     return req;
 }
 
diff --git a/src/Xxcbint.h b/src/Xxcbint.h
index bf41c23f..20a63864 100644
--- a/src/Xxcbint.h
+++ b/src/Xxcbint.h
@@ -13,12 +13,12 @@
 #include <X11/Xlib-xcb.h>
 #include "locking.h"
 
-#define XLIB_SEQUENCE_COMPARE(a,op,b)	(((long) (a) - (long) (b)) op 0)
+#define XLIB_SEQUENCE_COMPARE(a,op,b)	(((int64_t) (a) - (int64_t) (b)) op 0)
 
 typedef struct PendingRequest PendingRequest;
 struct PendingRequest {
 	PendingRequest *next;
-	unsigned long sequence;
+	uint64_t sequence;
 	unsigned reply_waiter;
 };
 
diff --git a/src/xcb_io.c b/src/xcb_io.c
index 59873296..bd26a62a 100644
--- a/src/xcb_io.c
+++ b/src/xcb_io.c
@@ -68,22 +68,8 @@ static void require_socket(Display *dpy)
 		if(!xcb_take_socket(dpy->xcb->connection, return_socket, dpy,
 		                    flags, &sent))
 			_XIOError(dpy);
-		/* Xlib uses unsigned long for sequence numbers.  XCB
-		 * uses 64-bit internally, but currently exposes an
-		 * unsigned int API.  If these differ, Xlib cannot track
-		 * the full 64-bit sequence number if 32-bit wrap
-		 * happens while Xlib does not own the socket.  A
-		 * complete fix would be to make XCB's public API use
-		 * 64-bit sequence numbers. */
-		if (sizeof(unsigned long) > sizeof(unsigned int) &&
-		    dpy->xcb->event_owner == XlibOwnsEventQueue &&
-		    (sent - dpy->last_request_read >= (UINT64_C(1) << 32))) {
-			throw_thread_fail_assert("Sequence number wrapped "
-			                         "beyond 32 bits while Xlib "
-						 "did not own the socket",
-			                         xcb_xlib_seq_number_wrapped);
-		}
-		dpy->xcb->last_flushed = dpy->request = sent;
+		dpy->xcb->last_flushed = sent;
+		X_DPY_SET_REQUEST(dpy, sent);
 		dpy->bufmax = dpy->xcb->real_bufmax;
 	}
 }
@@ -145,7 +131,7 @@ static void check_internal_connections(Display *dpy)
 		}
 }
 
-static PendingRequest *append_pending_request(Display *dpy, unsigned long sequence)
+static PendingRequest *append_pending_request(Display *dpy, uint64_t sequence)
 {
 	PendingRequest *node = malloc(sizeof(PendingRequest));
 	assert(node);
@@ -214,14 +200,13 @@ static int handle_error(Display *dpy, xError *err, Bool in_XReply)
 	return 0;
 }
 
-/* Widen a 32-bit sequence number into a native-word-size (unsigned long)
- * sequence number.  Treating the comparison as a 1 and shifting it avoids a
- * conditional branch, and shifting by 16 twice avoids a compiler warning when
- * sizeof(unsigned long) == 4. */
-static void widen(unsigned long *wide, unsigned int narrow)
+/* Widen a 32-bit sequence number into a 64bit (uint64_t) sequence number.
+ * Treating the comparison as a 1 and shifting it avoids a conditional branch.
+ */
+static void widen(uint64_t *wide, unsigned int narrow)
 {
-	unsigned long new = (*wide & ~0xFFFFFFFFUL) | narrow;
-	*wide = new + ((unsigned long) (new < *wide) << 16 << 16);
+	uint64_t new = (*wide & ~((uint64_t)0xFFFFFFFFUL)) | narrow;
+	*wide = new + (((uint64_t)(new < *wide)) << 32);
 }
 
 /* Thread-safety rules:
@@ -260,20 +245,20 @@ static xcb_generic_reply_t *poll_for_event(Display *dpy)
 	{
 		PendingRequest *req = dpy->xcb->pending_requests;
 		xcb_generic_event_t *event = dpy->xcb->next_event;
-		unsigned long event_sequence = dpy->last_request_read;
+		uint64_t event_sequence = X_DPY_GET_LAST_REQUEST_READ(dpy);
 		widen(&event_sequence, event->full_sequence);
 		if(!req || XLIB_SEQUENCE_COMPARE(event_sequence, <, req->sequence)
 		        || (event->response_type != X_Error && event_sequence == req->sequence))
 		{
-			if (XLIB_SEQUENCE_COMPARE(event_sequence, >,
-			                          dpy->request))
+			uint64_t request = X_DPY_GET_REQUEST(dpy);
+			if (XLIB_SEQUENCE_COMPARE(event_sequence, >, request))
 			{
 				throw_thread_fail_assert("Unknown sequence "
 				                         "number while "
 							 "processing queue",
 				                xcb_xlib_threads_sequence_lost);
 			}
-			dpy->last_request_read = event_sequence;
+			X_DPY_SET_LAST_REQUEST_READ(dpy, event_sequence);
 			dpy->xcb->next_event = NULL;
 			return (xcb_generic_reply_t *) event;
 		}
@@ -289,15 +274,16 @@ static xcb_generic_reply_t *poll_for_response(Display *dpy)
 	while(!(response = poll_for_event(dpy)) &&
 	      (req = dpy->xcb->pending_requests) &&
 	      !req->reply_waiter &&
-	      xcb_poll_for_reply(dpy->xcb->connection, req->sequence, &response, &error))
+	      xcb_poll_for_reply64(dpy->xcb->connection, req->sequence, &response, &error))
 	{
-		if(XLIB_SEQUENCE_COMPARE(req->sequence, >, dpy->request))
+		uint64_t request = X_DPY_GET_REQUEST(dpy);
+		if(XLIB_SEQUENCE_COMPARE(req->sequence, >, request))
 		{
 			throw_thread_fail_assert("Unknown sequence number "
 			                         "while awaiting reply",
 			                        xcb_xlib_threads_sequence_lost);
 		}
-		dpy->last_request_read = req->sequence;
+		X_DPY_SET_LAST_REQUEST_READ(dpy, req->sequence);
 		if(response)
 			break;
 		dequeue_pending_request(dpy, req);
@@ -456,6 +442,7 @@ void _XSend(Display *dpy, const char *data, long size)
 	static char const pad[3];
 	struct iovec vec[3];
 	uint64_t requests;
+	uint64_t dpy_request;
 	_XExtension *ext;
 	xcb_connection_t *c = dpy->xcb->connection;
 	if(dpy->flags & XlibDisplayIOError)
@@ -464,6 +451,10 @@ void _XSend(Display *dpy, const char *data, long size)
 	if(dpy->bufptr == dpy->buffer && !size)
 		return;
 
+	/* append_pending_request does not alter the dpy request number
+	 * therefore we can get it outside of the loop and the if
+	 */
+	dpy_request = X_DPY_GET_REQUEST(dpy);
 	/* iff we asked XCB to set aside errors, we must pick those up
 	 * eventually. iff there are async handlers, we may have just
 	 * issued requests that will generate replies. in either case,
@@ -471,11 +462,11 @@ void _XSend(Display *dpy, const char *data, long size)
 	if(dpy->xcb->event_owner != XlibOwnsEventQueue || dpy->async_handlers)
 	{
 		uint64_t sequence;
-		for(sequence = dpy->xcb->last_flushed + 1; sequence <= dpy->request; ++sequence)
+		for(sequence = dpy->xcb->last_flushed + 1; sequence <= dpy_request; ++sequence)
 			append_pending_request(dpy, sequence);
 	}
-	requests = dpy->request - dpy->xcb->last_flushed;
-	dpy->xcb->last_flushed = dpy->request;
+	requests = dpy_request - dpy->xcb->last_flushed;
+	dpy->xcb->last_flushed = dpy_request;
 
 	vec[0].iov_base = dpy->buffer;
 	vec[0].iov_len = dpy->bufptr - dpy->buffer;
@@ -570,6 +561,7 @@ Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard)
 	xcb_connection_t *c = dpy->xcb->connection;
 	char *reply;
 	PendingRequest *current;
+	uint64_t dpy_request;
 
 	if (dpy->xcb->reply_data)
 		throw_extlib_fail_assert("Extra reply data still left in queue",
@@ -579,10 +571,12 @@ Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard)
 		return 0;
 
 	_XSend(dpy, NULL, 0);
-	if(dpy->xcb->pending_requests_tail && dpy->xcb->pending_requests_tail->sequence == dpy->request)
+	dpy_request = X_DPY_GET_REQUEST(dpy);
+	if(dpy->xcb->pending_requests_tail
+	   && dpy->xcb->pending_requests_tail->sequence == dpy_request)
 		current = dpy->xcb->pending_requests_tail;
 	else
-		current = append_pending_request(dpy, dpy->request);
+		current = append_pending_request(dpy, dpy_request);
 	/* Don't let any other thread get this reply. */
 	current->reply_waiter = 1;
 
@@ -599,9 +593,9 @@ Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard)
 		}
 		req->reply_waiter = 1;
 		UnlockDisplay(dpy);
-		response = xcb_wait_for_reply(c, req->sequence, &error);
+		response = xcb_wait_for_reply64(c, req->sequence, &error);
 		/* Any user locks on another thread must have been taken
-		 * while we slept in xcb_wait_for_reply. Classic Xlib
+		 * while we slept in xcb_wait_for_reply64. Classic Xlib
 		 * ignored those user locks in this case, so we do too. */
 		InternalLockDisplay(dpy, /* ignore user locks */ 1);
 
@@ -629,12 +623,13 @@ Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard)
 
 		req->reply_waiter = 0;
 		ConditionBroadcast(dpy, dpy->xcb->reply_notify);
-		if(XLIB_SEQUENCE_COMPARE(req->sequence, >, dpy->request)) {
+		dpy_request = X_DPY_GET_REQUEST(dpy);
+		if(XLIB_SEQUENCE_COMPARE(req->sequence, >, dpy_request)) {
 			throw_thread_fail_assert("Unknown sequence number "
 			                         "while processing reply",
 			                        xcb_xlib_threads_sequence_lost);
 		}
-		dpy->last_request_read = req->sequence;
+		X_DPY_SET_LAST_REQUEST_READ(dpy, req->sequence);
 		if(!response)
 			dequeue_pending_request(dpy, req);
 
@@ -654,9 +649,10 @@ Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard)
 	if(dpy->xcb->next_event && dpy->xcb->next_event->response_type == X_Error)
 	{
 		xcb_generic_event_t *event = dpy->xcb->next_event;
-		unsigned long event_sequence = dpy->last_request_read;
+		uint64_t last_request_read = X_DPY_GET_LAST_REQUEST_READ(dpy);
+		uint64_t event_sequence = last_request_read;
 		widen(&event_sequence, event->full_sequence);
-		if(event_sequence == dpy->last_request_read)
+		if(event_sequence == last_request_read)
 		{
 			error = (xcb_generic_error_t *) event;
 			dpy->xcb->next_event = NULL;