git.demorecorder.com Git - free-sw/xcb/libxcb/blob - src/xcb_conn.c

   1 /* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp.
   2  *
   3  * Permission is hereby granted, free of charge, to any person obtaining a
   4  * copy of this software and associated documentation files (the "Software"),
   5  * to deal in the Software without restriction, including without limitation
   6  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   7  * and/or sell copies of the Software, and to permit persons to whom the
   8  * Software is furnished to do so, subject to the following conditions:
   9  *
  10  * The above copyright notice and this permission notice shall be included in
  11  * all copies or substantial portions of the Software.
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  15  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  16  * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  17  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  18  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19  *
  20  * Except as contained in this notice, the names of the authors or their
  21  * institutions shall not be used in advertising or otherwise to promote the
  22  * sale, use or other dealings in this Software without prior written
  23  * authorization from the authors.
  24  */
  25
  26 /* Connection management: the core of XCB. */
  27
  28 #include <assert.h>
  29 #include <string.h>
  30 #include <stdio.h>
  31 #include <unistd.h>
  32 #include <stdlib.h>
  33 #include <netinet/in.h>
  34 #include <sys/select.h>
  35 #include <sys/fcntl.h>
  36
  37 #include "xcb.h"
  38 #include "xcbint.h"
  39
  40 static int set_fd_flags(const int fd)
  41 {
  42     long flags = fcntl(fd, F_GETFL, 0);
  43     if(flags == -1)
  44         return 0;
  45     flags |= O_NONBLOCK;
  46     if(fcntl(fd, F_SETFL, flags) == -1)
  47         return 0;
  48     if(fcntl(fd, F_SETFD, FD_CLOEXEC) == -1)
  49         return 0;
  50     return 1;
  51 }
  52
  53 static int write_setup(XCBConnection *c, XCBAuthInfo *auth_info)
  54 {
  55     static const char pad[3];
  56     XCBConnSetupReq out;
  57     struct iovec parts[6];
  58     int count = 0;
  59     int endian = 0x01020304;
  60     int ret;
  61
  62     memset(&out, 0, sizeof(out));
  63
  64     /* B = 0x42 = MSB first, l = 0x6c = LSB first */
  65     if(htonl(endian) == endian)
  66         out.byte_order = 0x42;
  67     else
  68         out.byte_order = 0x6c;
  69     out.protocol_major_version = X_PROTOCOL;
  70     out.protocol_minor_version = X_PROTOCOL_REVISION;
  71     out.authorization_protocol_name_len = 0;
  72     out.authorization_protocol_data_len = 0;
  73     parts[count].iov_len = sizeof(XCBConnSetupReq);
  74     parts[count++].iov_base = &out;
  75     parts[count].iov_len = XCB_PAD(sizeof(XCBConnSetupReq));
  76     parts[count++].iov_base = (caddr_t) pad;
  77
  78     if(auth_info)
  79     {
  80         parts[count].iov_len = out.authorization_protocol_name_len = auth_info->namelen;
  81         parts[count++].iov_base = auth_info->name;
  82         parts[count].iov_len = XCB_PAD(out.authorization_protocol_name_len);
  83         parts[count++].iov_base = (caddr_t) pad;
  84         parts[count].iov_len = out.authorization_protocol_data_len = auth_info->datalen;
  85         parts[count++].iov_base = auth_info->data;
  86         parts[count].iov_len = XCB_PAD(out.authorization_protocol_data_len);
  87         parts[count++].iov_base = (caddr_t) pad;
  88     }
  89     assert(count <= sizeof(parts) / sizeof(*parts));
  90
  91     pthread_mutex_lock(&c->iolock);
  92     {
  93         struct iovec *parts_ptr = parts;
  94         ret = _xcb_out_send(c, &parts_ptr, &count);
  95     }
  96     pthread_mutex_unlock(&c->iolock);
  97     return ret;
  98 }
  99
 100 static int read_setup(XCBConnection *c)
 101 {
 102     /* Read the server response */
 103     c->setup = malloc(sizeof(XCBConnSetupGenericRep));
 104     if(!c->setup)
 105         return 0;
 106
 107     if(_xcb_in_read_block(c, c->setup, sizeof(XCBConnSetupGenericRep)) != sizeof(XCBConnSetupGenericRep))
 108         return 0;
 109
 110     {
 111         void *tmp = realloc(c->setup, c->setup->length * 4 + sizeof(XCBConnSetupGenericRep));
 112         if(!tmp)
 113             return 0;
 114         c->setup = tmp;
 115     }
 116
 117     if(_xcb_in_read_block(c, (char *) c->setup + sizeof(XCBConnSetupGenericRep), c->setup->length * 4) <= 0)
 118         return 0;
 119
 120     /* 0 = failed, 2 = authenticate, 1 = success */
 121     switch(c->setup->status)
 122     {
 123     case 0: /* failed */
 124         {
 125             XCBConnSetupFailedRep *setup = (XCBConnSetupFailedRep *) c->setup;
 126             write(STDERR_FILENO, XCBConnSetupFailedRepReason(setup), XCBConnSetupFailedRepReasonLength(setup));
 127             return 0;
 128         }
 129
 130     case 2: /* authenticate */
 131         {
 132             XCBConnSetupAuthenticateRep *setup = (XCBConnSetupAuthenticateRep *) c->setup;
 133             write(STDERR_FILENO, XCBConnSetupAuthenticateRepReason(setup), XCBConnSetupAuthenticateRepReasonLength(setup));
 134             return 0;
 135         }
 136     }
 137
 138     return 1;
 139 }
 140
 141 /* Public interface */
 142
 143 XCBConnSetupSuccessRep *XCBGetSetup(XCBConnection *c)
 144 {
 145     /* doesn't need locking because it's never written to. */
 146     return c->setup;
 147 }
 148
 149 int XCBGetFileDescriptor(XCBConnection *c)
 150 {
 151     /* doesn't need locking because it's never written to. */
 152     return c->fd;
 153 }
 154
 155 XCBConnection *XCBConnectToFD(int fd, XCBAuthInfo *auth_info)
 156 {
 157     XCBConnection* c;
 158
 159     c = calloc(1, sizeof(XCBConnection));
 160     if(!c)
 161         return 0;
 162
 163     c->fd = fd;
 164
 165     if(!(
 166         set_fd_flags(fd) &&
 167         pthread_mutex_init(&c->iolock, 0) == 0 &&
 168         _xcb_in_init(&c->in) &&
 169         _xcb_out_init(&c->out) &&
 170         write_setup(c, auth_info) &&
 171         read_setup(c) &&
 172         _xcb_ext_init(c) &&
 173         _xcb_xid_init(c)
 174         ))
 175     {
 176         XCBDisconnect(c);
 177         return 0;
 178     }
 179
 180     return c;
 181 }
 182
 183 void XCBDisconnect(XCBConnection *c)
 184 {
 185     if(!c)
 186         return;
 187
 188     free(c->setup);
 189     close(c->fd);
 190
 191     pthread_mutex_destroy(&c->iolock);
 192     _xcb_in_destroy(&c->in);
 193     _xcb_out_destroy(&c->out);
 194
 195     _xcb_ext_destroy(c);
 196     _xcb_xid_destroy(c);
 197
 198     free(c);
 199 }
 200
 201 /* Private interface */
 202
 203 int _xcb_conn_wait(XCBConnection *c, pthread_cond_t *cond, struct iovec **vector, int *count)
 204 {
 205     int ret;
 206     fd_set rfds, wfds;
 207
 208     /* If the thing I should be doing is already being done, wait for it. */
 209     if(count ? c->out.writing : c->in.reading)
 210     {
 211         pthread_cond_wait(cond, &c->iolock);
 212         return 1;
 213     }
 214
 215     FD_ZERO(&rfds);
 216     FD_SET(c->fd, &rfds);
 217     ++c->in.reading;
 218
 219     FD_ZERO(&wfds);
 220     if(count)
 221     {
 222         FD_SET(c->fd, &wfds);
 223         ++c->out.writing;
 224     }
 225
 226     pthread_mutex_unlock(&c->iolock);
 227     ret = select(c->fd + 1, &rfds, &wfds, 0, 0) > 0;
 228     pthread_mutex_lock(&c->iolock);
 229
 230     if(ret)
 231     {
 232         if(FD_ISSET(c->fd, &rfds))
 233             ret = ret && _xcb_in_read(c);
 234
 235         if(FD_ISSET(c->fd, &wfds))
 236             ret = ret && _xcb_out_write(c, vector, count);
 237     }
 238
 239     if(count)
 240         --c->out.writing;
 241     --c->in.reading;
 242
 243     return ret;
 244 }