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   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
  36 #include "xcb.h"
  37 #include "xcbint.h"
  38
  39 static int write_setup(XCBConnection *c, XCBAuthInfo *auth_info)
  40 {
  41     static const char pad[3];
  42     XCBConnSetupReq out;
  43     struct iovec parts[6];
  44     int count = 0;
  45     int endian = 0x01020304;
  46     int ret;
  47
  48     memset(&out, 0, sizeof(out));
  49
  50     /* B = 0x42 = MSB first, l = 0x6c = LSB first */
  51     if(htonl(endian) == endian)
  52         out.byte_order = 0x42;
  53     else
  54         out.byte_order = 0x6c;
  55     out.protocol_major_version = X_PROTOCOL;
  56     out.protocol_minor_version = X_PROTOCOL_REVISION;
  57     out.authorization_protocol_name_len = 0;
  58     out.authorization_protocol_data_len = 0;
  59     parts[count].iov_len = sizeof(XCBConnSetupReq);
  60     parts[count++].iov_base = &out;
  61     parts[count].iov_len = XCB_PAD(sizeof(XCBConnSetupReq));
  62     parts[count++].iov_base = (caddr_t) pad;
  63
  64     if(auth_info)
  65     {
  66         parts[count].iov_len = out.authorization_protocol_name_len = auth_info->namelen;
  67         parts[count++].iov_base = auth_info->name;
  68         parts[count].iov_len = XCB_PAD(out.authorization_protocol_name_len);
  69         parts[count++].iov_base = (caddr_t) pad;
  70         parts[count].iov_len = out.authorization_protocol_data_len = auth_info->datalen;
  71         parts[count++].iov_base = auth_info->data;
  72         parts[count].iov_len = XCB_PAD(out.authorization_protocol_data_len);
  73         parts[count++].iov_base = (caddr_t) pad;
  74     }
  75     assert(count <= sizeof(parts) / sizeof(*parts));
  76
  77     pthread_mutex_lock(&c->iolock);
  78     _xcb_out_write_block(c, parts, count);
  79     ret = _xcb_out_flush(c);
  80     pthread_mutex_unlock(&c->iolock);
  81     return ret;
  82 }
  83
  84 static int read_setup(XCBConnection *c)
  85 {
  86     /* Read the server response */
  87     c->setup = malloc(sizeof(XCBConnSetupGenericRep));
  88     if(!c->setup)
  89         return 0;
  90
  91     if(_xcb_in_read_block(c, c->setup, sizeof(XCBConnSetupGenericRep)) != sizeof(XCBConnSetupGenericRep))
  92         return 0;
  93
  94     {
  95         void *tmp = realloc(c->setup, c->setup->length * 4 + sizeof(XCBConnSetupGenericRep));
  96         if(!tmp)
  97             return 0;
  98         c->setup = tmp;
  99     }
 100
 101     if(_xcb_in_read_block(c, (char *) c->setup + sizeof(XCBConnSetupGenericRep), c->setup->length * 4) <= 0)
 102         return 0;
 103
 104     /* 0 = failed, 2 = authenticate, 1 = success */
 105     switch(c->setup->status)
 106     {
 107     case 0: /* failed */
 108         {
 109             XCBConnSetupFailedRep *setup = (XCBConnSetupFailedRep *) c->setup;
 110             write(STDERR_FILENO, XCBConnSetupFailedRepReason(setup), XCBConnSetupFailedRepReasonLength(setup));
 111             return 0;
 112         }
 113
 114     case 2: /* authenticate */
 115         {
 116             XCBConnSetupAuthenticateRep *setup = (XCBConnSetupAuthenticateRep *) c->setup;
 117             write(STDERR_FILENO, XCBConnSetupAuthenticateRepReason(setup), XCBConnSetupAuthenticateRepReasonLength(setup));
 118             return 0;
 119         }
 120     }
 121
 122     return 1;
 123 }
 124
 125 /* Public interface */
 126
 127 XCBConnSetupSuccessRep *XCBGetSetup(XCBConnection *c)
 128 {
 129     /* doesn't need locking because it's never written to. */
 130     return c->setup;
 131 }
 132
 133 int XCBGetFileDescriptor(XCBConnection *c)
 134 {
 135     /* doesn't need locking because it's never written to. */
 136     return c->fd;
 137 }
 138
 139 XCBConnection *XCBConnectToFD(int fd, XCBAuthInfo *auth_info)
 140 {
 141     XCBConnection* c;
 142
 143     c = calloc(1, sizeof(XCBConnection));
 144     if(!c)
 145         return 0;
 146
 147     c->fd = fd;
 148
 149     if(!(
 150         _xcb_set_fd_flags(fd) &&
 151         pthread_mutex_init(&c->iolock, 0) == 0 &&
 152         _xcb_in_init(&c->in) &&
 153         _xcb_out_init(&c->out) &&
 154         write_setup(c, auth_info) &&
 155         read_setup(c) &&
 156         _xcb_ext_init(c) &&
 157         _xcb_xid_init(c)
 158         ))
 159     {
 160         XCBDisconnect(c);
 161         return 0;
 162     }
 163
 164     return c;
 165 }
 166
 167 void XCBDisconnect(XCBConnection *c)
 168 {
 169     if(!c)
 170         return;
 171
 172     free(c->setup);
 173     close(c->fd);
 174
 175     pthread_mutex_destroy(&c->iolock);
 176     _xcb_in_destroy(&c->in);
 177     _xcb_out_destroy(&c->out);
 178
 179     _xcb_ext_destroy(c);
 180     _xcb_xid_destroy(c);
 181
 182     free(c);
 183 }
 184
 185 /* Private interface */
 186
 187 int _xcb_conn_wait(XCBConnection *c, const int should_write, pthread_cond_t *cond)
 188 {
 189     int ret;
 190     fd_set rfds, wfds;
 191
 192     /* If the thing I should be doing is already being done, wait for it. */
 193     if(should_write ? c->out.writing : c->in.reading)
 194     {
 195         pthread_cond_wait(cond, &c->iolock);
 196         return 1;
 197     }
 198
 199     FD_ZERO(&rfds);
 200     FD_SET(c->fd, &rfds);
 201     ++c->in.reading;
 202
 203     FD_ZERO(&wfds);
 204     if(should_write)
 205     {
 206         FD_SET(c->fd, &wfds);
 207         ++c->out.writing;
 208     }
 209
 210     pthread_mutex_unlock(&c->iolock);
 211     ret = select(c->fd + 1, &rfds, &wfds, 0, 0) > 0;
 212     pthread_mutex_lock(&c->iolock);
 213
 214     if(ret)
 215     {
 216         if(FD_ISSET(c->fd, &rfds))
 217             ret = ret && _xcb_in_read(c);
 218
 219         if(FD_ISSET(c->fd, &wfds))
 220             ret = ret && _xcb_out_write(c);
 221     }
 222
 223     if(should_write)
 224         --c->out.writing;
 225     --c->in.reading;
 226
 227     return ret;
 228 }