xenocara/dist/libxcb/src/xcb_in.c
2009-05-31 16:44:43 +00:00

591 lines
16 KiB
C

/* 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 <errno.h>
#include "xcb.h"
#include "xcbext.h"
#include "xcbint.h"
#if USE_POLL
#include <poll.h>
#else
#include <sys/select.h>
#endif
#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 reply_list {
void *reply;
struct reply_list *next;
};
typedef struct pending_reply {
uint64_t first_request;
uint64_t last_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;
int eventlength = 0; /* length after first 32 bytes for GenericEvents */
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)
{
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))
{
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 &&
!(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 == 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;
}
/* XGE events may have sizes > 32 */
if (genrep.response_type == XCB_XGE_EVENT)
{
eventlength = ((xcb_ge_event_t*)&genrep)->length * 4;
}
buf = malloc(length + eventlength +
(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;
}
/* 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(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);
free(buf);
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_32(reader->request, <=, c->in.request_read);
reader = reader->next)
{
if(XCB_SEQUENCE_COMPARE_32(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 ssize_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)
{
#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);
do {
ret = select(fd + 1, &fds, 0, 0, 0);
} while (ret == -1 && errno == EINTR);
#endif
}
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_32(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(XCB_SEQUENCE_COMPARE_32(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(XCB_SEQUENCE_COMPARE_32(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)
{
uint64_t widened_request;
void *ret = 0;
if(e)
*e = 0;
if(c->has_error)
return 0;
pthread_mutex_lock(&c->iolock);
widened_request = (c->out.request & UINT64_C(0xffffffff00000000)) | request;
if(widened_request > c->out.request)
widened_request -= UINT64_C(1) << 32;
/* If this request has not been written yet, write it. */
if(c->out.return_socket || _xcb_out_flush_to(c, widened_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_32((*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_32((*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);
pthread_mutex_unlock(&c->iolock);
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);
pthread_mutex_lock(&c->iolock);
ret = poll_for_reply(c, request, reply, error);
pthread_mutex_unlock(&c->iolock);
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;
pthread_mutex_lock(&c->iolock);
/* 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);
pthread_mutex_unlock(&c->iolock);
return ret;
}
xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c)
{
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 && _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_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_32(cookie.sequence,>,c->in.request_expected)
&& XCB_SEQUENCE_COMPARE_32(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, uint64_t 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->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;
}
void _xcb_in_replies_done(xcb_connection_t *c)
{
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 = 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;
}