/* Connection management: the core of XCB. */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
#include <assert.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
-#include <netinet/in.h>
-#include <sys/select.h>
#include <fcntl.h>
#include <errno.h>
+#include <limits.h>
#include "xcb.h"
#include "xcbint.h"
+#if USE_POLL
+#include <poll.h>
+#elif !defined _WIN32
+#include <sys/select.h>
+#endif
+
+#ifdef _WIN32
+#include "xcb_windefs.h"
+#else
+#include <sys/socket.h>
+#include <netinet/in.h>
+#endif /* _WIN32 */
+
+/* SHUT_RDWR is fairly recent and is not available on all platforms */
+#if !defined(SHUT_RDWR)
+#define SHUT_RDWR 2
+#endif
typedef struct {
uint8_t status;
uint16_t length;
} xcb_setup_generic_t;
-static const int error_connection = 1;
+static const xcb_setup_t xcb_error_setup = {
+ 0, /* status: failed (but we wouldn't have a xcb_setup_t in this case) */
+ 0, /* pad0 */
+ 0, 0, /* protocol version, should be 11.0, but isn't */
+ 0, /* length, invalid value */
+ 0, /* release_number */
+ 0, 0, /* resource_id_{base,mask} */
+ 0, /* motion_buffer_size */
+ 0, /* vendor_len */
+ 0, /* maximum_request_length */
+ 0, /* roots_len */
+ 0, /* pixmap_formats_len */
+ 0, /* image_byte_order */
+ 0, /* bitmap_format_bit_order */
+ 0, /* bitmap_format_scanline_unit */
+ 0, /* bitmap_format_scanline_pad */
+ 0, 0, /* {min,max}_keycode */
+ { 0, 0, 0, 0 } /* pad1 */
+};
+
+/* Keep this list in sync with is_static_error_conn()! */
+static const int xcb_con_error = XCB_CONN_ERROR;
+static const int xcb_con_closed_mem_er = XCB_CONN_CLOSED_MEM_INSUFFICIENT;
+static const int xcb_con_closed_parse_er = XCB_CONN_CLOSED_PARSE_ERR;
+static const int xcb_con_closed_screen_er = XCB_CONN_CLOSED_INVALID_SCREEN;
+
+static int is_static_error_conn(xcb_connection_t *c)
+{
+ return c == (xcb_connection_t *) &xcb_con_error ||
+ c == (xcb_connection_t *) &xcb_con_closed_mem_er ||
+ c == (xcb_connection_t *) &xcb_con_closed_parse_er ||
+ c == (xcb_connection_t *) &xcb_con_closed_screen_er;
+}
static int set_fd_flags(const int fd)
{
+/* Win32 doesn't have file descriptors and the fcntl function. This block sets the socket in non-blocking mode */
+
+#ifdef _WIN32
+ u_long iMode = 1; /* non-zero puts it in non-blocking mode, 0 in blocking mode */
+ int ret = 0;
+
+ ret = ioctlsocket(fd, FIONBIO, &iMode);
+ if(ret != 0)
+ return 0;
+ return 1;
+#else
int flags = fcntl(fd, F_GETFL, 0);
if(flags == -1)
return 0;
if(fcntl(fd, F_SETFD, FD_CLOEXEC) == -1)
return 0;
return 1;
-}
-
-static int _xcb_xlib_init(_xcb_xlib *xlib)
-{
- xlib->lock = 0;
-#ifndef NDEBUG
- xlib->sloppy_lock = (getenv("LIBXCB_ALLOW_SLOPPY_LOCK") != 0);
-#endif
- pthread_cond_init(&xlib->cond, 0);
- return 1;
-}
-
-static void _xcb_xlib_destroy(_xcb_xlib *xlib)
-{
- pthread_cond_destroy(&xlib->cond);
+#endif /* _WIN32 */
}
static int write_setup(xcb_connection_t *c, xcb_auth_info_t *auth_info)
xcb_setup_request_t out;
struct iovec parts[6];
int count = 0;
- int endian = 0x01020304;
+ static const uint32_t endian = 0x01020304;
int ret;
memset(&out, 0, sizeof(out));
parts[count].iov_len = XCB_PAD(out.authorization_protocol_data_len);
parts[count++].iov_base = (char *) pad;
}
- assert(count <= sizeof(parts) / sizeof(*parts));
+ assert(count <= (int) (sizeof(parts) / sizeof(*parts)));
- _xcb_lock_io(c);
- {
- struct iovec *parts_ptr = parts;
- ret = _xcb_out_send(c, &parts_ptr, &count);
- }
- _xcb_unlock_io(c);
+ pthread_mutex_lock(&c->iolock);
+ ret = _xcb_out_send(c, parts, count);
+ pthread_mutex_unlock(&c->iolock);
return ret;
}
{
int n;
assert(!c->out.queue_len);
- n = writev(c->fd, *vector, *count);
- if(n < 0 && errno == EAGAIN)
- return 1;
+
+#ifdef _WIN32
+ int i = 0;
+ int ret = 0,err = 0;
+ struct iovec *vec;
+ n = 0;
+
+ /* Could use the WSASend win32 function for scatter/gather i/o but setting up the WSABUF struct from
+ an iovec would require more work and I'm not sure of the benefit....works for now */
+ vec = *vector;
+ while(i < *count)
+ {
+ ret = send(c->fd,vec->iov_base,vec->iov_len,0);
+ if(ret == SOCKET_ERROR)
+ {
+ err = WSAGetLastError();
+ if(err == WSAEWOULDBLOCK)
+ {
+ return 1;
+ }
+ }
+ n += ret;
+ *vec++;
+ i++;
+ }
+#else
+ n = *count;
+ if (n > IOV_MAX)
+ n = IOV_MAX;
+
+#if HAVE_SENDMSG
+ if (c->out.out_fd.nfd) {
+ union {
+ struct cmsghdr cmsghdr;
+ char buf[CMSG_SPACE(XCB_MAX_PASS_FD * sizeof(int))];
+ } cmsgbuf;
+ struct msghdr msg = {
+ .msg_name = NULL,
+ .msg_namelen = 0,
+ .msg_iov = *vector,
+ .msg_iovlen = n,
+ .msg_control = cmsgbuf.buf,
+ .msg_controllen = CMSG_LEN(c->out.out_fd.nfd * sizeof (int)),
+ };
+ int i;
+ struct cmsghdr *hdr = CMSG_FIRSTHDR(&msg);
+
+ hdr->cmsg_len = msg.msg_controllen;
+ hdr->cmsg_level = SOL_SOCKET;
+ hdr->cmsg_type = SCM_RIGHTS;
+ memcpy(CMSG_DATA(hdr), c->out.out_fd.fd, c->out.out_fd.nfd * sizeof (int));
+
+ n = sendmsg(c->fd, &msg, 0);
+ if(n < 0 && errno == EAGAIN)
+ return 1;
+ for (i = 0; i < c->out.out_fd.nfd; i++)
+ close(c->out.out_fd.fd[i]);
+ c->out.out_fd.nfd = 0;
+ } else
+#endif
+ {
+ n = writev(c->fd, *vector, n);
+ if(n < 0 && errno == EAGAIN)
+ return 1;
+ }
+
+#endif /* _WIN32 */
+
if(n <= 0)
{
- _xcb_conn_shutdown(c);
+ _xcb_conn_shutdown(c, XCB_CONN_ERROR);
return 0;
}
const xcb_setup_t *xcb_get_setup(xcb_connection_t *c)
{
- if(c->has_error)
- return 0;
+ if(is_static_error_conn(c))
+ return &xcb_error_setup;
/* doesn't need locking because it's never written to. */
return c->setup;
}
int xcb_get_file_descriptor(xcb_connection_t *c)
{
- if(c->has_error)
+ if(is_static_error_conn(c))
return -1;
/* doesn't need locking because it's never written to. */
return c->fd;
{
xcb_connection_t* c;
+#ifndef _WIN32
+#ifndef USE_POLL
+ if(fd >= FD_SETSIZE) /* would overflow in FD_SET */
+ {
+ close(fd);
+ return _xcb_conn_ret_error(XCB_CONN_ERROR);
+ }
+#endif
+#endif /* !_WIN32*/
+
c = calloc(1, sizeof(xcb_connection_t));
- if(!c)
- return (xcb_connection_t *) &error_connection;
+ if(!c) {
+ close(fd);
+ return _xcb_conn_ret_error(XCB_CONN_CLOSED_MEM_INSUFFICIENT) ;
+ }
c->fd = fd;
if(!(
set_fd_flags(fd) &&
pthread_mutex_init(&c->iolock, 0) == 0 &&
- _xcb_xlib_init(&c->xlib) &&
_xcb_in_init(&c->in) &&
_xcb_out_init(&c->out) &&
write_setup(c, auth_info) &&
))
{
xcb_disconnect(c);
- return (xcb_connection_t *) &error_connection;
+ return _xcb_conn_ret_error(XCB_CONN_ERROR);
}
return c;
void xcb_disconnect(xcb_connection_t *c)
{
- if(c->has_error)
+ if(c == NULL || is_static_error_conn(c))
return;
free(c->setup);
+
+ /* disallow further sends and receives */
+ shutdown(c->fd, SHUT_RDWR);
close(c->fd);
pthread_mutex_destroy(&c->iolock);
- _xcb_xlib_destroy(&c->xlib);
_xcb_in_destroy(&c->in);
_xcb_out_destroy(&c->out);
_xcb_xid_destroy(c);
free(c);
+
+#ifdef _WIN32
+ WSACleanup();
+#endif
}
/* Private interface */
-void _xcb_conn_shutdown(xcb_connection_t *c)
+void _xcb_conn_shutdown(xcb_connection_t *c, int err)
{
- c->has_error = 1;
+ c->has_error = err;
}
-void _xcb_lock_io(xcb_connection_t *c)
-{
- pthread_mutex_lock(&c->iolock);
- while(c->xlib.lock)
- {
- if(pthread_equal(c->xlib.thread, pthread_self()))
- break;
- pthread_cond_wait(&c->xlib.cond, &c->iolock);
- }
-}
-
-void _xcb_unlock_io(xcb_connection_t *c)
+/* Return connection error state.
+ * To make thread-safe, I need a seperate static
+ * variable for every possible error.
+ * has_error is the first field in xcb_connection_t, so just
+ * return a casted int here; checking has_error (and only
+ * has_error) will be safe.
+ */
+xcb_connection_t *_xcb_conn_ret_error(int err)
{
- pthread_mutex_unlock(&c->iolock);
-}
-void _xcb_wait_io(xcb_connection_t *c, pthread_cond_t *cond)
-{
- int xlib_locked = c->xlib.lock;
- if(xlib_locked)
- {
- c->xlib.lock = 0;
- pthread_cond_broadcast(&c->xlib.cond);
- }
- pthread_cond_wait(cond, &c->iolock);
- if(xlib_locked)
+ switch(err)
{
- while(c->xlib.lock)
- pthread_cond_wait(&c->xlib.cond, &c->iolock);
- c->xlib.lock = 1;
- c->xlib.thread = pthread_self();
+ case XCB_CONN_CLOSED_MEM_INSUFFICIENT:
+ {
+ return (xcb_connection_t *) &xcb_con_closed_mem_er;
+ }
+ case XCB_CONN_CLOSED_PARSE_ERR:
+ {
+ return (xcb_connection_t *) &xcb_con_closed_parse_er;
+ }
+ case XCB_CONN_CLOSED_INVALID_SCREEN:
+ {
+ return (xcb_connection_t *) &xcb_con_closed_screen_er;
+ }
+ case XCB_CONN_ERROR:
+ default:
+ {
+ return (xcb_connection_t *) &xcb_con_error;
+ }
}
}
int _xcb_conn_wait(xcb_connection_t *c, pthread_cond_t *cond, struct iovec **vector, int *count)
{
- int ret, xlib_locked;
+ int ret;
+#if USE_POLL
+ struct pollfd fd;
+#else
fd_set rfds, wfds;
+#endif
/* If the thing I should be doing is already being done, wait for it. */
if(count ? c->out.writing : c->in.reading)
{
- _xcb_wait_io(c, cond);
+ pthread_cond_wait(cond, &c->iolock);
return 1;
}
+#if USE_POLL
+ memset(&fd, 0, sizeof(fd));
+ fd.fd = c->fd;
+ fd.events = POLLIN;
+#else
FD_ZERO(&rfds);
FD_SET(c->fd, &rfds);
+#endif
++c->in.reading;
+#if USE_POLL
+ if(count)
+ {
+ fd.events |= POLLOUT;
+ ++c->out.writing;
+ }
+#else
FD_ZERO(&wfds);
if(count)
{
FD_SET(c->fd, &wfds);
++c->out.writing;
}
+#endif
- xlib_locked = c->xlib.lock;
- if(xlib_locked)
- {
- c->xlib.lock = 0;
- pthread_cond_broadcast(&c->xlib.cond);
- }
- _xcb_unlock_io(c);
+ pthread_mutex_unlock(&c->iolock);
do {
- ret = select(c->fd + 1, &rfds, &wfds, 0, 0);
+#if USE_POLL
+ ret = poll(&fd, 1, -1);
+ /* If poll() returns an event we didn't expect, such as POLLNVAL, treat
+ * it as if it failed. */
+ if(ret >= 0 && (fd.revents & ~fd.events))
+ {
+ ret = -1;
+ break;
+ }
+#else
+ ret = select(c->fd + 1, &rfds, &wfds, 0, 0);
+#endif
} while (ret == -1 && errno == EINTR);
- if (ret < 0)
+ if(ret < 0)
{
- _xcb_conn_shutdown(c);
- ret = 0;
- }
- _xcb_lock_io(c);
- if(xlib_locked)
- {
- c->xlib.lock = 1;
- c->xlib.thread = pthread_self();
+ _xcb_conn_shutdown(c, XCB_CONN_ERROR);
+ ret = 0;
}
+ pthread_mutex_lock(&c->iolock);
if(ret)
{
- if(FD_ISSET(c->fd, &rfds))
+ /* The code allows two threads to call select()/poll() at the same time.
+ * First thread just wants to read, a second thread wants to write, too.
+ * We have to make sure that we don't steal the reading thread's reply
+ * and let it get stuck in select()/poll().
+ * So a thread may read if either:
+ * - There is no other thread that wants to read (the above situation
+ * did not occur).
+ * - It is the reading thread (above situation occurred).
+ */
+ int may_read = c->in.reading == 1 || !count;
+#if USE_POLL
+ if(may_read && (fd.revents & POLLIN) != 0)
+#else
+ if(may_read && FD_ISSET(c->fd, &rfds))
+#endif
ret = ret && _xcb_in_read(c);
+#if USE_POLL
+ if((fd.revents & POLLOUT) != 0)
+#else
if(FD_ISSET(c->fd, &wfds))
+#endif
ret = ret && write_vec(c, vector, count);
}