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-rw-r--r--libX11/src/xcb_io.c1261
1 files changed, 684 insertions, 577 deletions
diff --git a/libX11/src/xcb_io.c b/libX11/src/xcb_io.c
index aa10f6657..3733e1521 100644
--- a/libX11/src/xcb_io.c
+++ b/libX11/src/xcb_io.c
@@ -1,577 +1,684 @@
-/* Copyright (C) 2003-2006 Jamey Sharp, Josh Triplett
- * This file is licensed under the MIT license. See the file COPYING. */
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
-#include "Xlibint.h"
-#include "locking.h"
-#include "Xprivate.h"
-#include "Xxcbint.h"
-#include <xcb/xcbext.h>
-
-#include <assert.h>
-#include <inttypes.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-#ifdef HAVE_SYS_SELECT_H
-#include <sys/select.h>
-#endif
-#include <sys/time.h>
-
-#include <X11/Xtrans/Xtrans.h>
-
-static void return_socket(void *closure)
-{
- Display *dpy = closure;
- LockDisplay(dpy);
- _XSend(dpy, NULL, 0);
- dpy->bufmax = dpy->buffer;
- UnlockDisplay(dpy);
-}
-
-static void require_socket(Display *dpy)
-{
- if(dpy->bufmax == dpy->buffer)
- {
- uint64_t sent;
- int flags = 0;
- /* if we don't own the event queue, we have to ask XCB
- * to set our errors aside for us. */
- if(dpy->xcb->event_owner != XlibOwnsEventQueue)
- flags = XCB_REQUEST_CHECKED;
- 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. */
- assert(!(sizeof(unsigned long) > sizeof(unsigned int)
- && dpy->xcb->event_owner == XlibOwnsEventQueue
- && (sent - dpy->last_request_read >= (UINT64_C(1) << 32))));
- dpy->xcb->last_flushed = dpy->request = sent;
- dpy->bufmax = dpy->xcb->real_bufmax;
- }
-}
-
-/* Call internal connection callbacks for any fds that are currently
- * ready to read. This function will not block unless one of the
- * callbacks blocks.
- *
- * This code borrowed from _XWaitForReadable. Inverse call tree:
- * _XRead
- * _XWaitForWritable
- * _XFlush
- * _XSend
- * _XEventsQueued
- * _XReadEvents
- * _XRead[0-9]+
- * _XAllocIDs
- * _XReply
- * _XEatData
- * _XReadPad
- */
-static void check_internal_connections(Display *dpy)
-{
- struct _XConnectionInfo *ilist;
- fd_set r_mask;
- struct timeval tv;
- int result;
- int highest_fd = -1;
-
- if(dpy->flags & XlibDisplayProcConni || !dpy->im_fd_info)
- return;
-
- FD_ZERO(&r_mask);
- for(ilist = dpy->im_fd_info; ilist; ilist = ilist->next)
- {
- assert(ilist->fd >= 0);
- FD_SET(ilist->fd, &r_mask);
- if(ilist->fd > highest_fd)
- highest_fd = ilist->fd;
- }
- assert(highest_fd >= 0);
-
- tv.tv_sec = 0;
- tv.tv_usec = 0;
- result = select(highest_fd + 1, &r_mask, NULL, NULL, &tv);
-
- if(result == -1)
- {
- if(errno == EINTR)
- return;
- _XIOError(dpy);
- }
-
- for(ilist = dpy->im_fd_info; result && ilist; ilist = ilist->next)
- if(FD_ISSET(ilist->fd, &r_mask))
- {
- _XProcessInternalConnection(dpy, ilist);
- --result;
- }
-}
-
-static void call_handlers(Display *dpy, xcb_generic_reply_t *buf)
-{
- _XAsyncHandler *async, *next;
- for(async = dpy->async_handlers; async; async = next)
- {
- next = async->next;
- if(async->handler(dpy, (xReply *) buf, (char *) buf, sizeof(xReply) + (buf->length << 2), async->data))
- return;
- }
- if(buf->response_type == 0) /* unhandled error */
- _XError(dpy, (xError *) buf);
-}
-
-static xcb_generic_event_t * wait_or_poll_for_event(Display *dpy, int wait)
-{
- xcb_connection_t *c = dpy->xcb->connection;
- xcb_generic_event_t *event;
- if(wait)
- {
- if(dpy->xcb->event_waiter)
- {
- ConditionWait(dpy, dpy->xcb->event_notify);
- event = xcb_poll_for_event(c);
- }
- else
- {
- dpy->xcb->event_waiter = 1;
- UnlockDisplay(dpy);
- event = xcb_wait_for_event(c);
- LockDisplay(dpy);
- dpy->xcb->event_waiter = 0;
- ConditionBroadcast(dpy, dpy->xcb->event_notify);
- }
- }
- else
- event = xcb_poll_for_event(c);
- return event;
-}
-
-/* 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)
-{
- unsigned long new = (*wide & ~0xFFFFFFFFUL) | narrow;
- *wide = new + ((unsigned long) (new < *wide) << 16 << 16);
-}
-
-static void process_responses(Display *dpy, int wait_for_first_event, xcb_generic_error_t **current_error, unsigned long current_request)
-{
- void *reply;
- xcb_generic_event_t *event = dpy->xcb->next_event;
- xcb_generic_error_t *error;
- xcb_connection_t *c = dpy->xcb->connection;
- if(!event && dpy->xcb->event_owner == XlibOwnsEventQueue)
- event = wait_or_poll_for_event(dpy, wait_for_first_event);
-
- require_socket(dpy);
-
- while(1)
- {
- PendingRequest *req = dpy->xcb->pending_requests;
- unsigned long event_sequence = dpy->last_request_read;
- if(event)
- widen(&event_sequence, event->full_sequence);
- assert(!(req && current_request && !XLIB_SEQUENCE_COMPARE(req->sequence, <=, current_request)));
- if(event && (!req || XLIB_SEQUENCE_COMPARE(event_sequence, <=, req->sequence)))
- {
- dpy->last_request_read = event_sequence;
- if(event->response_type != X_Error)
- {
- /* GenericEvents may be > 32 bytes. In this
- * case, the event struct is trailed by the
- * additional bytes. the xcb_generic_event_t
- * struct uses 4 bytes for internal numbering,
- * so we need to shift the trailing data to be
- * after the first 32 bytes. */
- if (event->response_type == GenericEvent &&
- ((xcb_ge_event_t*)event)->length)
- {
- memmove(&event->full_sequence,
- &event[1],
- ((xcb_ge_event_t*)event)->length * 4);
- }
- _XEnq(dpy, (xEvent *) event);
- wait_for_first_event = 0;
- }
- else if(current_error && event_sequence == current_request)
- {
- /* This can only occur when called from
- * _XReply, which doesn't need a new event. */
- *current_error = (xcb_generic_error_t *) event;
- event = NULL;
- break;
- }
- else
- _XError(dpy, (xError *) event);
- free(event);
- event = wait_or_poll_for_event(dpy, wait_for_first_event);
- }
- else if(req && req->sequence == current_request)
- {
- break;
- }
- else if(req && xcb_poll_for_reply(dpy->xcb->connection, req->sequence, &reply, &error))
- {
- uint64_t sequence = req->sequence;
- if(!reply)
- {
- dpy->xcb->pending_requests = req->next;
- if(!dpy->xcb->pending_requests)
- dpy->xcb->pending_requests_tail = &dpy->xcb->pending_requests;
- free(req);
- reply = error;
- }
- if(reply)
- {
- dpy->last_request_read = sequence;
- call_handlers(dpy, reply);
- free(reply);
- }
- }
- else
- break;
- }
-
- dpy->xcb->next_event = event;
-
- if(xcb_connection_has_error(c))
- _XIOError(dpy);
-
- assert(XLIB_SEQUENCE_COMPARE(dpy->last_request_read, <=, dpy->request));
-}
-
-int _XEventsQueued(Display *dpy, int mode)
-{
- if(dpy->flags & XlibDisplayIOError)
- return 0;
- if(dpy->xcb->event_owner != XlibOwnsEventQueue)
- return 0;
-
- if(mode == QueuedAfterFlush)
- _XSend(dpy, NULL, 0);
- else
- check_internal_connections(dpy);
- process_responses(dpy, 0, NULL, 0);
- return dpy->qlen;
-}
-
-/* _XReadEvents - Flush the output queue,
- * then read as many events as possible (but at least 1) and enqueue them
- */
-void _XReadEvents(Display *dpy)
-{
- if(dpy->flags & XlibDisplayIOError)
- return;
- _XSend(dpy, NULL, 0);
- if(dpy->xcb->event_owner != XlibOwnsEventQueue)
- return;
- check_internal_connections(dpy);
- do {
- process_responses(dpy, 1, NULL, 0);
- } while (dpy->qlen == 0);
-}
-
-/*
- * _XSend - Flush the buffer and send the client data. 32 bit word aligned
- * transmission is used, if size is not 0 mod 4, extra bytes are transmitted.
- *
- * Note that the connection must not be read from once the data currently
- * in the buffer has been written.
- */
-void _XSend(Display *dpy, const char *data, long size)
-{
- static const xReq dummy_request;
- static char const pad[3];
- struct iovec vec[3];
- uint64_t requests;
- _XExtension *ext;
- xcb_connection_t *c = dpy->xcb->connection;
- if(dpy->flags & XlibDisplayIOError)
- return;
-
- if(dpy->bufptr == dpy->buffer && !size)
- return;
-
- /* 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,
- * we need to remember to check later. */
- if(dpy->xcb->event_owner != XlibOwnsEventQueue || dpy->async_handlers)
- {
- uint64_t sequence;
- for(sequence = dpy->xcb->last_flushed; sequence < dpy->request; ++sequence)
- {
- PendingRequest *req = malloc(sizeof(PendingRequest));
- assert(req);
- req->next = NULL;
- req->sequence = sequence;
- *dpy->xcb->pending_requests_tail = req;
- dpy->xcb->pending_requests_tail = &req->next;
- }
- }
- 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;
- vec[1].iov_base = (caddr_t) data;
- vec[1].iov_len = size;
- vec[2].iov_base = (caddr_t) pad;
- vec[2].iov_len = -size & 3;
-
- for(ext = dpy->flushes; ext; ext = ext->next_flush)
- {
- int i;
- for(i = 0; i < 3; ++i)
- if(vec[i].iov_len)
- ext->before_flush(dpy, &ext->codes, vec[i].iov_base, vec[i].iov_len);
- }
-
- if(xcb_writev(c, vec, 3, requests) < 0)
- _XIOError(dpy);
- dpy->bufptr = dpy->buffer;
- dpy->last_req = (char *) &dummy_request;
-
- check_internal_connections(dpy);
-
- _XSetSeqSyncFunction(dpy);
-}
-
-/*
- * _XFlush - Flush the X request buffer. If the buffer is empty, no
- * action is taken.
- */
-void _XFlush(Display *dpy)
-{
- require_socket(dpy);
- _XSend(dpy, NULL, 0);
-
- _XEventsQueued(dpy, QueuedAfterReading);
-}
-
-static const XID inval_id = ~0UL;
-
-int _XIDHandler(Display *dpy)
-{
- XID next;
-
- if (dpy->xcb->next_xid != inval_id)
- return 0;
-
- next = xcb_generate_id(dpy->xcb->connection);
- LockDisplay(dpy);
- dpy->xcb->next_xid = next;
-#ifdef XTHREADS
- if (dpy->lock)
- (*dpy->lock->user_unlock_display)(dpy);
-#endif
- UnlockDisplay(dpy);
- return 0;
-}
-
-/* _XAllocID - resource ID allocation routine. */
-XID _XAllocID(Display *dpy)
-{
- XID ret = dpy->xcb->next_xid;
- assert (ret != inval_id);
-#ifdef XTHREADS
- if (dpy->lock)
- (*dpy->lock->user_lock_display)(dpy);
-#endif
- dpy->xcb->next_xid = inval_id;
- _XSetPrivSyncFunction(dpy);
- return ret;
-}
-
-/* _XAllocIDs - multiple resource ID allocation routine. */
-void _XAllocIDs(Display *dpy, XID *ids, int count)
-{
- int i;
-#ifdef XTHREADS
- if (dpy->lock)
- (*dpy->lock->user_lock_display)(dpy);
- UnlockDisplay(dpy);
-#endif
- for (i = 0; i < count; i++)
- ids[i] = xcb_generate_id(dpy->xcb->connection);
-#ifdef XTHREADS
- LockDisplay(dpy);
- if (dpy->lock)
- (*dpy->lock->user_unlock_display)(dpy);
-#endif
-}
-
-static void _XFreeReplyData(Display *dpy, Bool force)
-{
- if(!force && dpy->xcb->reply_consumed < dpy->xcb->reply_length)
- return;
- free(dpy->xcb->reply_data);
- dpy->xcb->reply_data = NULL;
-}
-
-static PendingRequest * insert_pending_request(Display *dpy)
-{
- PendingRequest **cur = &dpy->xcb->pending_requests;
- while(*cur && XLIB_SEQUENCE_COMPARE((*cur)->sequence, <, dpy->request))
- cur = &((*cur)->next);
- if(!*cur || (*cur)->sequence != dpy->request)
- {
- PendingRequest *node = malloc(sizeof(PendingRequest));
- assert(node);
- node->next = *cur;
- node->sequence = dpy->request;
- if(cur == dpy->xcb->pending_requests_tail)
- dpy->xcb->pending_requests_tail = &(node->next);
- *cur = node;
- }
- return *cur;
-}
-
-/*
- * _XReply - Wait for a reply packet and copy its contents into the
- * specified rep.
- * extra: number of 32-bit words expected after the reply
- * discard: should I discard data following "extra" words?
- */
-Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard)
-{
- xcb_generic_error_t *error;
- xcb_connection_t *c = dpy->xcb->connection;
- char *reply;
- PendingRequest *current;
-
- assert(!dpy->xcb->reply_data);
-
- if(dpy->flags & XlibDisplayIOError)
- return 0;
-
- _XSend(dpy, NULL, 0);
- current = insert_pending_request(dpy);
- /* FIXME: drop the Display lock while waiting?
- * Complicates process_responses. */
- reply = xcb_wait_for_reply(c, current->sequence, &error);
-
- check_internal_connections(dpy);
- process_responses(dpy, 0, &error, current->sequence);
-
- if(error)
- {
- _XExtension *ext;
- xError *err = (xError *) error;
- int ret_code;
-
- dpy->last_request_read = error->full_sequence;
-
- /* Xlib is evil and assumes that even errors will be
- * copied into rep. */
- memcpy(rep, error, 32);
-
- /* do not die on "no such font", "can't allocate",
- "can't grab" failures */
- switch(err->errorCode)
- {
- case BadName:
- switch(err->majorCode)
- {
- case X_LookupColor:
- case X_AllocNamedColor:
- free(error);
- return 0;
- }
- break;
- case BadFont:
- if(err->majorCode == X_QueryFont) {
- free(error);
- return 0;
- }
- break;
- case BadAlloc:
- case BadAccess:
- free(error);
- return 0;
- }
-
- /*
- * we better see if there is an extension who may
- * want to suppress the error.
- */
- for(ext = dpy->ext_procs; ext; ext = ext->next)
- if(ext->error && ext->error(dpy, err, &ext->codes, &ret_code)) {
- free(error);
- return ret_code;
- }
-
- _XError(dpy, err);
- free(error);
- return 0;
- }
-
- /* it's not an error, but we don't have a reply, so it's an I/O
- * error. */
- if(!reply)
- {
- _XIOError(dpy);
- return 0;
- }
-
- dpy->last_request_read = current->sequence;
-
- /* there's no error and we have a reply. */
- dpy->xcb->reply_data = reply;
- dpy->xcb->reply_consumed = sizeof(xReply) + (extra * 4);
- dpy->xcb->reply_length = sizeof(xReply);
- if(dpy->xcb->reply_data[0] == 1)
- dpy->xcb->reply_length += (((xcb_generic_reply_t *) dpy->xcb->reply_data)->length * 4);
-
- /* error: Xlib asks too much. give them what we can anyway. */
- if(dpy->xcb->reply_length < dpy->xcb->reply_consumed)
- dpy->xcb->reply_consumed = dpy->xcb->reply_length;
-
- memcpy(rep, dpy->xcb->reply_data, dpy->xcb->reply_consumed);
- _XFreeReplyData(dpy, discard);
- return 1;
-}
-
-int _XRead(Display *dpy, char *data, long size)
-{
- assert(size >= 0);
- if(size == 0)
- return 0;
- assert(dpy->xcb->reply_data != NULL);
- assert(dpy->xcb->reply_consumed + size <= dpy->xcb->reply_length);
- memcpy(data, dpy->xcb->reply_data + dpy->xcb->reply_consumed, size);
- dpy->xcb->reply_consumed += size;
- _XFreeReplyData(dpy, False);
- return 0;
-}
-
-/*
- * _XReadPad - Read bytes from the socket taking into account incomplete
- * reads. If the number of bytes is not 0 mod 4, read additional pad
- * bytes.
- */
-void _XReadPad(Display *dpy, char *data, long size)
-{
- _XRead(dpy, data, size);
- dpy->xcb->reply_consumed += -size & 3;
- _XFreeReplyData(dpy, False);
-}
-
-/* Read and discard "n" 8-bit bytes of data */
-void _XEatData(Display *dpy, unsigned long n)
-{
- dpy->xcb->reply_consumed += n;
- _XFreeReplyData(dpy, False);
-}
+/* Copyright (C) 2003-2006 Jamey Sharp, Josh Triplett
+ * This file is licensed under the MIT license. See the file COPYING. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "Xlibint.h"
+#include "locking.h"
+#include "Xprivate.h"
+#include "Xxcbint.h"
+#include <xcb/xcbext.h>
+
+#include <assert.h>
+#ifdef HAVE_INTTYPES_H
+#include <inttypes.h>
+#endif
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_SYS_SELECT_H
+#include <sys/select.h>
+#endif
+#include <sys/time.h>
+
+#include <X11/Xtrans/Xtrans.h>
+
+static void return_socket(void *closure)
+{
+ Display *dpy = closure;
+ InternalLockDisplay(dpy, /* don't skip user locks */ 0);
+ _XSend(dpy, NULL, 0);
+ dpy->bufmax = dpy->buffer;
+ UnlockDisplay(dpy);
+}
+
+static void require_socket(Display *dpy)
+{
+ if(dpy->bufmax == dpy->buffer)
+ {
+ uint64_t sent;
+ int flags = 0;
+ /* if we don't own the event queue, we have to ask XCB
+ * to set our errors aside for us. */
+ if(dpy->xcb->event_owner != XlibOwnsEventQueue)
+ flags = XCB_REQUEST_CHECKED;
+ 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. */
+ assert(!(sizeof(unsigned long) > sizeof(unsigned int)
+ && dpy->xcb->event_owner == XlibOwnsEventQueue
+ && (sent - dpy->last_request_read >= (UINT64_C(1) << 32))));
+ dpy->xcb->last_flushed = dpy->request = sent;
+ dpy->bufmax = dpy->xcb->real_bufmax;
+ }
+}
+
+/* Call internal connection callbacks for any fds that are currently
+ * ready to read. This function will not block unless one of the
+ * callbacks blocks.
+ *
+ * This code borrowed from _XWaitForReadable. Inverse call tree:
+ * _XRead
+ * _XWaitForWritable
+ * _XFlush
+ * _XSend
+ * _XEventsQueued
+ * _XReadEvents
+ * _XRead[0-9]+
+ * _XAllocIDs
+ * _XReply
+ * _XEatData
+ * _XReadPad
+ */
+static void check_internal_connections(Display *dpy)
+{
+ struct _XConnectionInfo *ilist;
+ fd_set r_mask;
+ struct timeval tv;
+ int result;
+ int highest_fd = -1;
+
+ if(dpy->flags & XlibDisplayProcConni || !dpy->im_fd_info)
+ return;
+
+ FD_ZERO(&r_mask);
+ for(ilist = dpy->im_fd_info; ilist; ilist = ilist->next)
+ {
+ assert(ilist->fd >= 0);
+ FD_SET(ilist->fd, &r_mask);
+ if(ilist->fd > highest_fd)
+ highest_fd = ilist->fd;
+ }
+ assert(highest_fd >= 0);
+
+ tv.tv_sec = 0;
+ tv.tv_usec = 0;
+ result = select(highest_fd + 1, &r_mask, NULL, NULL, &tv);
+
+ if(result == -1)
+ {
+ if(errno == EINTR)
+ return;
+ _XIOError(dpy);
+ }
+
+ for(ilist = dpy->im_fd_info; result && ilist; ilist = ilist->next)
+ if(FD_ISSET(ilist->fd, &r_mask))
+ {
+ _XProcessInternalConnection(dpy, ilist);
+ --result;
+ }
+}
+
+static PendingRequest *append_pending_request(Display *dpy, unsigned long sequence)
+{
+ PendingRequest *node = malloc(sizeof(PendingRequest));
+ assert(node);
+ node->next = NULL;
+ node->sequence = sequence;
+ node->reply_waiter = 0;
+ if(dpy->xcb->pending_requests_tail)
+ {
+ assert(XLIB_SEQUENCE_COMPARE(dpy->xcb->pending_requests_tail->sequence, <, node->sequence));
+ assert(dpy->xcb->pending_requests_tail->next == NULL);
+ dpy->xcb->pending_requests_tail->next = node;
+ }
+ else
+ dpy->xcb->pending_requests = node;
+ dpy->xcb->pending_requests_tail = node;
+ return node;
+}
+
+static void dequeue_pending_request(Display *dpy, PendingRequest *req)
+{
+ assert(req == dpy->xcb->pending_requests);
+ dpy->xcb->pending_requests = req->next;
+ if(!dpy->xcb->pending_requests)
+ {
+ assert(req == dpy->xcb->pending_requests_tail);
+ dpy->xcb->pending_requests_tail = NULL;
+ }
+ else
+ assert(XLIB_SEQUENCE_COMPARE(req->sequence, <, dpy->xcb->pending_requests->sequence));
+ free(req);
+}
+
+static int handle_error(Display *dpy, xError *err, Bool in_XReply)
+{
+ _XExtension *ext;
+ int ret_code;
+ /* Oddly, Xlib only allows extensions to suppress errors when
+ * those errors were seen by _XReply. */
+ if(in_XReply)
+ /*
+ * we better see if there is an extension who may
+ * want to suppress the error.
+ */
+ for(ext = dpy->ext_procs; ext; ext = ext->next)
+ if(ext->error && (*ext->error)(dpy, err, &ext->codes, &ret_code))
+ return ret_code;
+ _XError(dpy, err);
+ 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)
+{
+ unsigned long new = (*wide & ~0xFFFFFFFFUL) | narrow;
+ *wide = new + ((unsigned long) (new < *wide) << 16 << 16);
+}
+
+/* Thread-safety rules:
+ *
+ * At most one thread can be reading from XCB's event queue at a time.
+ * If you are not the current event-reading thread and you need to find
+ * out if an event is available, you must wait.
+ *
+ * The same rule applies for reading replies.
+ *
+ * A single thread cannot be both the the event-reading and the
+ * reply-reading thread at the same time.
+ *
+ * We always look at both the current event and the first pending reply
+ * to decide which to process next.
+ *
+ * We always process all responses in sequence-number order, which may
+ * mean waiting for another thread (either the event_waiter or the
+ * reply_waiter) to handle an earlier response before we can process or
+ * return a later one. If so, we wait on the corresponding condition
+ * variable for that thread to process the response and wake us up.
+ */
+
+static xcb_generic_reply_t *poll_for_event(Display *dpy)
+{
+ /* Make sure the Display's sequence numbers are valid */
+ require_socket(dpy);
+
+ /* Precondition: This thread can safely get events from XCB. */
+ assert(dpy->xcb->event_owner == XlibOwnsEventQueue && !dpy->xcb->event_waiter);
+
+ if(!dpy->xcb->next_event)
+ dpy->xcb->next_event = xcb_poll_for_event(dpy->xcb->connection);
+
+ if(dpy->xcb->next_event)
+ {
+ PendingRequest *req = dpy->xcb->pending_requests;
+ xcb_generic_event_t *event = dpy->xcb->next_event;
+ unsigned long event_sequence = dpy->last_request_read;
+ widen(&event_sequence, event->full_sequence);
+ if(!req || XLIB_SEQUENCE_COMPARE(event_sequence, <, req->sequence)
+ || (event->response_type != X_Error && event_sequence == req->sequence))
+ {
+ assert(XLIB_SEQUENCE_COMPARE(event_sequence, <=, dpy->request));
+ dpy->last_request_read = event_sequence;
+ dpy->xcb->next_event = NULL;
+ return (xcb_generic_reply_t *) event;
+ }
+ }
+ return NULL;
+}
+
+static xcb_generic_reply_t *poll_for_response(Display *dpy)
+{
+ void *response;
+ xcb_generic_error_t *error;
+ PendingRequest *req;
+ 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))
+ {
+ assert(XLIB_SEQUENCE_COMPARE(req->sequence, <=, dpy->request));
+ dpy->last_request_read = req->sequence;
+ if(!response)
+ dequeue_pending_request(dpy, req);
+ if(error)
+ return (xcb_generic_reply_t *) error;
+ }
+ return response;
+}
+
+static void handle_response(Display *dpy, xcb_generic_reply_t *response, Bool in_XReply)
+{
+ _XAsyncHandler *async, *next;
+ switch(response->response_type)
+ {
+ case X_Reply:
+ for(async = dpy->async_handlers; async; async = next)
+ {
+ next = async->next;
+ if(async->handler(dpy, (xReply *) response, (char *) response, sizeof(xReply) + (response->length << 2), async->data))
+ break;
+ }
+ break;
+
+ case X_Error:
+ handle_error(dpy, (xError *) response, in_XReply);
+ break;
+
+ default: /* event */
+ /* GenericEvents may be > 32 bytes. In this case, the
+ * event struct is trailed by the additional bytes. the
+ * xcb_generic_event_t struct uses 4 bytes for internal
+ * numbering, so we need to shift the trailing data to
+ * be after the first 32 bytes. */
+ if(response->response_type == GenericEvent && ((xcb_ge_event_t *) response)->length)
+ {
+ xcb_ge_event_t *event = (xcb_ge_event_t *) response;
+ memmove(&event->full_sequence, &event[1], event->length * 4);
+ }
+ _XEnq(dpy, (xEvent *) response);
+ break;
+ }
+ free(response);
+}
+
+int _XEventsQueued(Display *dpy, int mode)
+{
+ xcb_generic_reply_t *response;
+ if(dpy->flags & XlibDisplayIOError)
+ return 0;
+ if(dpy->xcb->event_owner != XlibOwnsEventQueue)
+ return 0;
+
+ if(mode == QueuedAfterFlush)
+ _XSend(dpy, NULL, 0);
+ else
+ check_internal_connections(dpy);
+
+ /* If another thread is blocked waiting for events, then we must
+ * let that thread pick up the next event. Since it blocked, we
+ * can reasonably claim there are no new events right now. */
+ if(!dpy->xcb->event_waiter)
+ {
+ while((response = poll_for_response(dpy)))
+ handle_response(dpy, response, False);
+ if(xcb_connection_has_error(dpy->xcb->connection))
+ _XIOError(dpy);
+ }
+ return dpy->qlen;
+}
+
+/* _XReadEvents - Flush the output queue,
+ * then read as many events as possible (but at least 1) and enqueue them
+ */
+void _XReadEvents(Display *dpy)
+{
+ xcb_generic_reply_t *response;
+ unsigned long serial;
+
+ if(dpy->flags & XlibDisplayIOError)
+ return;
+ _XSend(dpy, NULL, 0);
+ if(dpy->xcb->event_owner != XlibOwnsEventQueue)
+ return;
+ check_internal_connections(dpy);
+
+ serial = dpy->next_event_serial_num;
+ while(serial == dpy->next_event_serial_num || dpy->qlen == 0)
+ {
+ if(dpy->xcb->event_waiter)
+ {
+ ConditionWait(dpy, dpy->xcb->event_notify);
+ /* Maybe the other thread got us an event. */
+ continue;
+ }
+
+ if(!dpy->xcb->next_event)
+ {
+ xcb_generic_event_t *event;
+ dpy->xcb->event_waiter = 1;
+ UnlockDisplay(dpy);
+ event = xcb_wait_for_event(dpy->xcb->connection);
+ InternalLockDisplay(dpy, /* don't skip user locks */ 0);
+ dpy->xcb->event_waiter = 0;
+ ConditionBroadcast(dpy, dpy->xcb->event_notify);
+ if(!event)
+ _XIOError(dpy);
+ dpy->xcb->next_event = event;
+ }
+
+ /* We've established most of the conditions for
+ * poll_for_response to return non-NULL. The exceptions
+ * are connection shutdown, and finding that another
+ * thread is waiting for the next reply we'd like to
+ * process. */
+
+ response = poll_for_response(dpy);
+ if(response)
+ handle_response(dpy, response, False);
+ else if(dpy->xcb->pending_requests->reply_waiter)
+ { /* need braces around ConditionWait */
+ ConditionWait(dpy, dpy->xcb->reply_notify);
+ }
+ else
+ _XIOError(dpy);
+ }
+
+ /* The preceding loop established that there is no
+ * event_waiter--unless we just called ConditionWait because of
+ * a reply_waiter, in which case another thread may have become
+ * the event_waiter while we slept unlocked. */
+ if(!dpy->xcb->event_waiter)
+ while((response = poll_for_response(dpy)))
+ handle_response(dpy, response, False);
+ if(xcb_connection_has_error(dpy->xcb->connection))
+ _XIOError(dpy);
+}
+
+/*
+ * _XSend - Flush the buffer and send the client data. 32 bit word aligned
+ * transmission is used, if size is not 0 mod 4, extra bytes are transmitted.
+ *
+ * Note that the connection must not be read from once the data currently
+ * in the buffer has been written.
+ */
+void _XSend(Display *dpy, const char *data, long size)
+{
+ static const xReq dummy_request;
+ static char const pad[3];
+ struct iovec vec[3];
+ uint64_t requests;
+ _XExtension *ext;
+ xcb_connection_t *c = dpy->xcb->connection;
+ if(dpy->flags & XlibDisplayIOError)
+ return;
+
+ if(dpy->bufptr == dpy->buffer && !size)
+ return;
+
+ /* 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,
+ * we need to remember to check later. */
+ if(dpy->xcb->event_owner != XlibOwnsEventQueue || dpy->async_handlers)
+ {
+ uint64_t 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;
+
+ vec[0].iov_base = dpy->buffer;
+ vec[0].iov_len = dpy->bufptr - dpy->buffer;
+ vec[1].iov_base = (caddr_t) data;
+ vec[1].iov_len = size;
+ vec[2].iov_base = (caddr_t) pad;
+ vec[2].iov_len = -size & 3;
+
+ for(ext = dpy->flushes; ext; ext = ext->next_flush)
+ {
+ int i;
+ for(i = 0; i < 3; ++i)
+ if(vec[i].iov_len)
+ ext->before_flush(dpy, &ext->codes, vec[i].iov_base, vec[i].iov_len);
+ }
+
+ if(xcb_writev(c, vec, 3, requests) < 0)
+ _XIOError(dpy);
+ dpy->bufptr = dpy->buffer;
+ dpy->last_req = (char *) &dummy_request;
+
+ check_internal_connections(dpy);
+
+ _XSetSeqSyncFunction(dpy);
+}
+
+/*
+ * _XFlush - Flush the X request buffer. If the buffer is empty, no
+ * action is taken.
+ */
+void _XFlush(Display *dpy)
+{
+ require_socket(dpy);
+ _XSend(dpy, NULL, 0);
+
+ _XEventsQueued(dpy, QueuedAfterReading);
+}
+
+static const XID inval_id = ~0UL;
+
+void _XIDHandler(Display *dpy)
+{
+ if (dpy->xcb->next_xid == inval_id)
+ _XAllocIDs(dpy, &dpy->xcb->next_xid, 1);
+}
+
+/* _XAllocID - resource ID allocation routine. */
+XID _XAllocID(Display *dpy)
+{
+ XID ret = dpy->xcb->next_xid;
+ assert (ret != inval_id);
+ dpy->xcb->next_xid = inval_id;
+ _XSetPrivSyncFunction(dpy);
+ return ret;
+}
+
+/* _XAllocIDs - multiple resource ID allocation routine. */
+void _XAllocIDs(Display *dpy, XID *ids, int count)
+{
+ int i;
+#ifdef XTHREADS
+ if (dpy->lock)
+ (*dpy->lock->user_lock_display)(dpy);
+ UnlockDisplay(dpy);
+#endif
+ for (i = 0; i < count; i++)
+ ids[i] = xcb_generate_id(dpy->xcb->connection);
+#ifdef XTHREADS
+ InternalLockDisplay(dpy, /* don't skip user locks */ 0);
+ if (dpy->lock)
+ (*dpy->lock->user_unlock_display)(dpy);
+#endif
+}
+
+static void _XFreeReplyData(Display *dpy, Bool force)
+{
+ if(!force && dpy->xcb->reply_consumed < dpy->xcb->reply_length)
+ return;
+ free(dpy->xcb->reply_data);
+ dpy->xcb->reply_data = NULL;
+}
+
+/*
+ * _XReply - Wait for a reply packet and copy its contents into the
+ * specified rep.
+ * extra: number of 32-bit words expected after the reply
+ * discard: should I discard data following "extra" words?
+ */
+Status _XReply(Display *dpy, xReply *rep, int extra, Bool discard)
+{
+ xcb_generic_error_t *error;
+ xcb_connection_t *c = dpy->xcb->connection;
+ char *reply;
+ PendingRequest *current;
+
+ assert(!dpy->xcb->reply_data);
+
+ if(dpy->flags & XlibDisplayIOError)
+ return 0;
+
+ _XSend(dpy, NULL, 0);
+ 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);
+ /* Don't let any other thread get this reply. */
+ current->reply_waiter = 1;
+
+ while(1)
+ {
+ PendingRequest *req = dpy->xcb->pending_requests;
+ xcb_generic_reply_t *response;
+
+ if(req != current && req->reply_waiter)
+ {
+ ConditionWait(dpy, dpy->xcb->reply_notify);
+ /* Another thread got this reply. */
+ continue;
+ }
+ req->reply_waiter = 1;
+ UnlockDisplay(dpy);
+ response = xcb_wait_for_reply(c, req->sequence, &error);
+ InternalLockDisplay(dpy, /* don't skip user locks */ 0);
+
+ /* We have the response we're looking for. Now, before
+ * letting anyone else process this sequence number, we
+ * need to process any events that should have come
+ * earlier. */
+
+ if(dpy->xcb->event_owner == XlibOwnsEventQueue)
+ {
+ xcb_generic_reply_t *event;
+ /* If some thread is already waiting for events,
+ * it will get the first one. That thread must
+ * process that event before we can continue. */
+ /* FIXME: That event might be after this reply,
+ * and might never even come--or there might be
+ * multiple threads trying to get events. */
+ while(dpy->xcb->event_waiter)
+ { /* need braces around ConditionWait */
+ ConditionWait(dpy, dpy->xcb->event_notify);
+ }
+ while((event = poll_for_event(dpy)))
+ handle_response(dpy, event, True);
+ }
+
+ req->reply_waiter = 0;
+ ConditionBroadcast(dpy, dpy->xcb->reply_notify);
+ assert(XLIB_SEQUENCE_COMPARE(req->sequence, <=, dpy->request));
+ dpy->last_request_read = req->sequence;
+ if(!response)
+ dequeue_pending_request(dpy, req);
+
+ if(req == current)
+ {
+ reply = (char *) response;
+ break;
+ }
+
+ if(error)
+ handle_response(dpy, (xcb_generic_reply_t *) error, True);
+ else if(response)
+ handle_response(dpy, response, True);
+ }
+ check_internal_connections(dpy);
+
+ 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;
+ widen(&event_sequence, event->full_sequence);
+ if(event_sequence == current->sequence)
+ {
+ error = (xcb_generic_error_t *) event;
+ dpy->xcb->next_event = NULL;
+ }
+ }
+
+ if(error)
+ {
+ int ret_code;
+
+ /* Xlib is evil and assumes that even errors will be
+ * copied into rep. */
+ memcpy(rep, error, 32);
+
+ /* do not die on "no such font", "can't allocate",
+ "can't grab" failures */
+ switch(error->error_code)
+ {
+ case BadName:
+ switch(error->major_code)
+ {
+ case X_LookupColor:
+ case X_AllocNamedColor:
+ free(error);
+ return 0;
+ }
+ break;
+ case BadFont:
+ if(error->major_code == X_QueryFont) {
+ free(error);
+ return 0;
+ }
+ break;
+ case BadAlloc:
+ case BadAccess:
+ free(error);
+ return 0;
+ }
+
+ ret_code = handle_error(dpy, (xError *) error, True);
+ free(error);
+ return ret_code;
+ }
+
+ /* it's not an error, but we don't have a reply, so it's an I/O
+ * error. */
+ if(!reply)
+ {
+ _XIOError(dpy);
+ return 0;
+ }
+
+ /* there's no error and we have a reply. */
+ dpy->xcb->reply_data = reply;
+ dpy->xcb->reply_consumed = sizeof(xReply) + (extra * 4);
+ dpy->xcb->reply_length = sizeof(xReply);
+ if(dpy->xcb->reply_data[0] == 1)
+ dpy->xcb->reply_length += (((xcb_generic_reply_t *) dpy->xcb->reply_data)->length * 4);
+
+ /* error: Xlib asks too much. give them what we can anyway. */
+ if(dpy->xcb->reply_length < dpy->xcb->reply_consumed)
+ dpy->xcb->reply_consumed = dpy->xcb->reply_length;
+
+ memcpy(rep, dpy->xcb->reply_data, dpy->xcb->reply_consumed);
+ _XFreeReplyData(dpy, discard);
+ return 1;
+}
+
+int _XRead(Display *dpy, char *data, long size)
+{
+ assert(size >= 0);
+ if(size == 0)
+ return 0;
+ assert(dpy->xcb->reply_data != NULL);
+ assert(dpy->xcb->reply_consumed + size <= dpy->xcb->reply_length);
+ memcpy(data, dpy->xcb->reply_data + dpy->xcb->reply_consumed, size);
+ dpy->xcb->reply_consumed += size;
+ _XFreeReplyData(dpy, False);
+ return 0;
+}
+
+/*
+ * _XReadPad - Read bytes from the socket taking into account incomplete
+ * reads. If the number of bytes is not 0 mod 4, read additional pad
+ * bytes.
+ */
+void _XReadPad(Display *dpy, char *data, long size)
+{
+ _XRead(dpy, data, size);
+ dpy->xcb->reply_consumed += -size & 3;
+ _XFreeReplyData(dpy, False);
+}
+
+/* Read and discard "n" 8-bit bytes of data */
+void _XEatData(Display *dpy, unsigned long n)
+{
+ dpy->xcb->reply_consumed += n;
+ _XFreeReplyData(dpy, False);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 12:02:10 +0000