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-rw-r--r--libxcb/src/xcb_in.c530
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diff --git a/libxcb/src/xcb_in.c b/libxcb/src/xcb_in.c
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+/* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the names of the authors or their
+ * institutions shall not be used in advertising or otherwise to promote the
+ * sale, use or other dealings in this Software without prior written
+ * authorization from the authors.
+ */
+
+/* Stuff that reads stuff from the server. */
+
+#include <assert.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/select.h>
+#include <errno.h>
+
+#include "xcb.h"
+#include "xcbext.h"
+#include "xcbint.h"
+
+#define XCB_ERROR 0
+#define XCB_REPLY 1
+
+struct event_list {
+ xcb_generic_event_t *event;
+ struct event_list *next;
+};
+
+struct reply_list {
+ void *reply;
+ struct reply_list *next;
+};
+
+typedef struct pending_reply {
+ unsigned int request;
+ enum workarounds workaround;
+ int flags;
+ struct pending_reply *next;
+} pending_reply;
+
+typedef struct reader_list {
+ unsigned int request;
+ pthread_cond_t *data;
+ struct reader_list *next;
+} reader_list;
+
+static void 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);
+}
+
+static int read_packet(xcb_connection_t *c)
+{
+ xcb_generic_reply_t genrep;
+ int length = 32;
+ void *buf;
+ pending_reply *pend = 0;
+ struct event_list *event;
+
+ /* Wait for there to be enough data for us to read a whole packet */
+ if(c->in.queue_len < length)
+ return 0;
+
+ /* Get the response type, length, and sequence number. */
+ memcpy(&genrep, c->in.queue, sizeof(genrep));
+
+ /* Compute 32-bit sequence number of this packet. */
+ if((genrep.response_type & 0x7f) != XCB_KEYMAP_NOTIFY)
+ {
+ unsigned int lastread = c->in.request_read;
+ c->in.request_read = (lastread & 0xffff0000) | 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 &&
+ XCB_SEQUENCE_COMPARE (c->in.pending_replies->request, <=, c->in.request_completed))
+ {
+ pending_reply *oldpend = c->in.pending_replies;
+ c->in.pending_replies = oldpend->next;
+ if(!oldpend->next)
+ c->in.pending_replies_tail = &c->in.pending_replies;
+ free(oldpend);
+ }
+
+ if(genrep.response_type == XCB_ERROR)
+ c->in.request_completed = c->in.request_read;
+ }
+
+ if(genrep.response_type == XCB_ERROR || genrep.response_type == XCB_REPLY)
+ {
+ pend = c->in.pending_replies;
+ if(pend && pend->request != c->in.request_read)
+ pend = 0;
+ }
+
+ /* For reply packets, check that the entire packet is available. */
+ if(genrep.response_type == XCB_REPLY)
+ {
+ if(pend && pend->workaround == WORKAROUND_GLX_GET_FB_CONFIGS_BUG)
+ {
+ uint32_t *p = (uint32_t *) c->in.queue;
+ genrep.length = p[2] * p[3] * 2;
+ }
+ length += genrep.length * 4;
+ }
+
+ buf = malloc(length + (genrep.response_type == XCB_REPLY ? 0 : sizeof(uint32_t)));
+ if(!buf)
+ {
+ _xcb_conn_shutdown(c);
+ return 0;
+ }
+ if(_xcb_in_read_block(c, buf, length) <= 0)
+ {
+ free(buf);
+ return 0;
+ }
+ if(pend && (pend->flags & XCB_REQUEST_DISCARD_REPLY))
+ {
+ free(buf);
+ return 1;
+ }
+
+ if(genrep.response_type != XCB_REPLY)
+ ((xcb_generic_event_t *) buf)->full_sequence = c->in.request_read;
+
+ /* reply, or checked error */
+ if( genrep.response_type == XCB_REPLY ||
+ (genrep.response_type == XCB_ERROR && pend && (pend->flags & XCB_REQUEST_CHECKED)))
+ {
+ reader_list *reader;
+ struct reply_list *cur = malloc(sizeof(struct reply_list));
+ if(!cur)
+ {
+ _xcb_conn_shutdown(c);
+ return 0;
+ }
+ cur->reply = buf;
+ cur->next = 0;
+ *c->in.current_reply_tail = cur;
+ c->in.current_reply_tail = &cur->next;
+ for(reader = c->in.readers;
+ reader &&
+ XCB_SEQUENCE_COMPARE(reader->request, <=, c->in.request_read);
+ reader = reader->next)
+ {
+ if(reader->request == c->in.request_read)
+ {
+ pthread_cond_signal(reader->data);
+ break;
+ }
+ }
+ return 1;
+ }
+
+ /* event, or unchecked error */
+ event = malloc(sizeof(struct event_list));
+ if(!event)
+ {
+ _xcb_conn_shutdown(c);
+ free(buf);
+ return 0;
+ }
+ event->event = buf;
+ event->next = 0;
+ *c->in.events_tail = event;
+ c->in.events_tail = &event->next;
+ pthread_cond_signal(&c->in.event_cond);
+ return 1; /* I have something for you... */
+}
+
+static xcb_generic_event_t *get_event(xcb_connection_t *c)
+{
+ struct event_list *cur = c->in.events;
+ xcb_generic_event_t *ret;
+ if(!c->in.events)
+ return 0;
+ ret = cur->event;
+ c->in.events = cur->next;
+ if(!cur->next)
+ c->in.events_tail = &c->in.events;
+ free(cur);
+ return ret;
+}
+
+static void free_reply_list(struct reply_list *head)
+{
+ while(head)
+ {
+ struct reply_list *cur = head;
+ head = cur->next;
+ free(cur->reply);
+ free(cur);
+ }
+}
+
+static int read_block(const int fd, void *buf, const size_t len)
+{
+ int done = 0;
+ while(done < len)
+ {
+ int ret = read(fd, ((char *) buf) + done, len - done);
+ if(ret > 0)
+ done += ret;
+ if(ret < 0 && errno == EAGAIN)
+ {
+ fd_set fds;
+ FD_ZERO(&fds);
+ FD_SET(fd, &fds);
+ do {
+ ret = select(fd + 1, &fds, 0, 0, 0);
+ } while (ret == -1 && errno == EINTR);
+ }
+ if(ret <= 0)
+ return ret;
+ }
+ return len;
+}
+
+static int poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error)
+{
+ struct reply_list *head;
+
+ /* If an error occurred when issuing the request, fail immediately. */
+ if(!request)
+ head = 0;
+ /* We've read requests past the one we want, so if it has replies we have
+ * them all and they're in the replies map. */
+ else if(XCB_SEQUENCE_COMPARE(request, <, c->in.request_read))
+ {
+ head = _xcb_map_remove(c->in.replies, request);
+ if(head && head->next)
+ _xcb_map_put(c->in.replies, request, head->next);
+ }
+ /* We're currently processing the responses to the request we want, and we
+ * have a reply ready to return. So just return it without blocking. */
+ else if(request == c->in.request_read && c->in.current_reply)
+ {
+ head = c->in.current_reply;
+ c->in.current_reply = head->next;
+ if(!head->next)
+ c->in.current_reply_tail = &c->in.current_reply;
+ }
+ /* We know this request can't have any more replies, and we've already
+ * established it doesn't have a reply now. Don't bother blocking. */
+ else if(request == c->in.request_completed)
+ head = 0;
+ /* We may have more replies on the way for this request: block until we're
+ * sure. */
+ else
+ return 0;
+
+ if(error)
+ *error = 0;
+ *reply = 0;
+
+ if(head)
+ {
+ if(((xcb_generic_reply_t *) head->reply)->response_type == XCB_ERROR)
+ {
+ if(error)
+ *error = head->reply;
+ else
+ free(head->reply);
+ }
+ else
+ *reply = head->reply;
+
+ free(head);
+ }
+
+ return 1;
+}
+
+/* Public interface */
+
+void *xcb_wait_for_reply(xcb_connection_t *c, unsigned int request, xcb_generic_error_t **e)
+{
+ void *ret = 0;
+ if(e)
+ *e = 0;
+ if(c->has_error)
+ return 0;
+
+ _xcb_lock_io(c);
+
+ /* If this request has not been written yet, write it. */
+ if(_xcb_out_flush_to(c, request))
+ {
+ pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+ reader_list reader;
+ reader_list **prev_reader;
+
+ for(prev_reader = &c->in.readers;
+ *prev_reader &&
+ XCB_SEQUENCE_COMPARE ((*prev_reader)->request, <=, request);
+ prev_reader = &(*prev_reader)->next)
+ {
+ /* empty */;
+ }
+ reader.request = request;
+ reader.data = &cond;
+ reader.next = *prev_reader;
+ *prev_reader = &reader;
+
+ while(!poll_for_reply(c, request, &ret, e))
+ if(!_xcb_conn_wait(c, &cond, 0, 0))
+ break;
+
+ for(prev_reader = &c->in.readers;
+ *prev_reader &&
+ XCB_SEQUENCE_COMPARE((*prev_reader)->request, <=, request);
+ prev_reader = &(*prev_reader)->next)
+ {
+ if(*prev_reader == &reader)
+ {
+ *prev_reader = (*prev_reader)->next;
+ break;
+ }
+ }
+ pthread_cond_destroy(&cond);
+ }
+
+ wake_up_next_reader(c);
+ _xcb_unlock_io(c);
+ return ret;
+}
+
+int xcb_poll_for_reply(xcb_connection_t *c, unsigned int request, void **reply, xcb_generic_error_t **error)
+{
+ int ret;
+ if(c->has_error)
+ {
+ *reply = 0;
+ if(error)
+ *error = 0;
+ return 1; /* would not block */
+ }
+ assert(reply != 0);
+ _xcb_lock_io(c);
+ ret = poll_for_reply(c, request, reply, error);
+ _xcb_unlock_io(c);
+ return ret;
+}
+
+xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c)
+{
+ xcb_generic_event_t *ret;
+ if(c->has_error)
+ return 0;
+ _xcb_lock_io(c);
+ /* 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_unlock_io(c);
+ return ret;
+}
+
+xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c)
+{
+ xcb_generic_event_t *ret = 0;
+ if(!c->has_error)
+ {
+ _xcb_lock_io(c);
+ /* FIXME: follow X meets Z architecture changes. */
+ ret = get_event(c);
+ if(!ret && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */
+ ret = get_event(c);
+ _xcb_unlock_io(c);
+ }
+ return ret;
+}
+
+xcb_generic_error_t *xcb_request_check(xcb_connection_t *c, xcb_void_cookie_t cookie)
+{
+ /* FIXME: this could hold the lock to avoid syncing unnecessarily, but
+ * that would require factoring the locking out of xcb_get_input_focus,
+ * xcb_get_input_focus_reply, and xcb_wait_for_reply. */
+ xcb_generic_error_t *ret;
+ void *reply;
+ if(c->has_error)
+ return 0;
+ if(XCB_SEQUENCE_COMPARE(cookie.sequence,>,c->in.request_expected)
+ && XCB_SEQUENCE_COMPARE(cookie.sequence,>,c->in.request_completed))
+ {
+ free(xcb_get_input_focus_reply(c, xcb_get_input_focus(c), &ret));
+ assert(!ret);
+ }
+ reply = xcb_wait_for_reply(c, cookie.sequence, &ret);
+ assert(!reply);
+ return ret;
+}
+
+/* Private interface */
+
+int _xcb_in_init(_xcb_in *in)
+{
+ if(pthread_cond_init(&in->event_cond, 0))
+ return 0;
+ in->reading = 0;
+
+ in->queue_len = 0;
+
+ in->request_read = 0;
+ in->request_completed = 0;
+
+ in->replies = _xcb_map_new();
+ if(!in->replies)
+ return 0;
+
+ in->current_reply_tail = &in->current_reply;
+ in->events_tail = &in->events;
+ in->pending_replies_tail = &in->pending_replies;
+
+ return 1;
+}
+
+void _xcb_in_destroy(_xcb_in *in)
+{
+ pthread_cond_destroy(&in->event_cond);
+ free_reply_list(in->current_reply);
+ _xcb_map_delete(in->replies, (void (*)(void *)) free_reply_list);
+ while(in->events)
+ {
+ struct event_list *e = in->events;
+ in->events = e->next;
+ free(e->event);
+ free(e);
+ }
+ while(in->pending_replies)
+ {
+ pending_reply *pend = in->pending_replies;
+ in->pending_replies = pend->next;
+ free(pend);
+ }
+}
+
+int _xcb_in_expect_reply(xcb_connection_t *c, unsigned int request, enum workarounds workaround, int flags)
+{
+ pending_reply *pend = malloc(sizeof(pending_reply));
+ assert(workaround != WORKAROUND_NONE || flags != 0);
+ if(!pend)
+ {
+ _xcb_conn_shutdown(c);
+ return 0;
+ }
+ pend->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(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)
+ c->in.queue_len += n;
+ while(read_packet(c))
+ /* empty */;
+ if((n > 0) || (n < 0 && errno == EAGAIN))
+ return 1;
+ _xcb_conn_shutdown(c);
+ return 0;
+}
+
+int _xcb_in_read_block(xcb_connection_t *c, void *buf, int len)
+{
+ int done = c->in.queue_len;
+ if(len < done)
+ done = len;
+
+ memcpy(buf, c->in.queue, done);
+ c->in.queue_len -= done;
+ memmove(c->in.queue, c->in.queue + done, c->in.queue_len);
+
+ if(len > done)
+ {
+ int ret = read_block(c->fd, (char *) buf + done, len - done);
+ if(ret <= 0)
+ {
+ _xcb_conn_shutdown(c);
+ return ret;
+ }
+ }
+
+ return len;
+}