src/waffle/core/wcore_display.c

   1 // Copyright 2012 Intel Corporation
   2 //
   3 // All rights reserved.
   4 //
   5 // Redistribution and use in source and binary forms, with or without
   6 // modification, are permitted provided that the following conditions are met:
   7 //
   8 // - Redistributions of source code must retain the above copyright notice, this
   9 //   list of conditions and the following disclaimer.
  10 //
  11 // - Redistributions in binary form must reproduce the above copyright notice,
  12 //   this list of conditions and the following disclaimer in the documentation
  13 //   and/or other materials provided with the distribution.
  14 //
  15 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  16 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  18 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  19 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  21 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  22 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  23 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  24 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25
  26 #include <assert.h>
  27 #include <stdio.h>
  28
  29 #include "wcore_display.h"
  30
  31 static mtx_t mutex;
  32
  33 static void
  34 wcore_display_init_once(void)
  35 {
  36     mtx_init(&mutex, mtx_plain);
  37 }
  38
  39 bool
  40 wcore_display_init(struct wcore_display *self,
  41                    struct wcore_platform *platform)
  42 {
  43     static size_t id_counter = 0;
  44     static once_flag flag = ONCE_FLAG_INIT;
  45
  46     assert(self);
  47     assert(platform);
  48
  49     call_once(&flag, wcore_display_init_once);
  50     mtx_lock(&mutex);
  51     self->api.display_id = ++id_counter;
  52     mtx_unlock(&mutex);
  53
  54     self->platform = platform;
  55
  56     if (self->api.display_id == 0) {
  57         fprintf(stderr, "waffle: error: internal counter wrapped to 0\n");
  58         abort();
  59     }
  60
  61     return true;
  62 }