src/pulsecore/x11prop.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2004-2006 Lennart Poettering
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2.1 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <string.h>
  27
  28 #include "x11prop.h"
  29
  30 #include <pulsecore/macro.h>
  31
  32 #include <xcb/xproto.h>
  33 #include <xcb/xcb_atom.h>
  34
  35 #define PA_XCB_FORMAT 8
  36
  37 static xcb_screen_t *screen_of_display(xcb_connection_t *xcb, int screen) {
  38     const xcb_setup_t *s;
  39     xcb_screen_iterator_t iter;
  40
  41     if ((s = xcb_get_setup(xcb))) {
  42         iter = xcb_setup_roots_iterator(s);
  43         for (; iter.rem; --screen, xcb_screen_next(&iter))
  44             if (0 == screen)
  45                 return iter.data;
  46     }
  47     return NULL;
  48 }
  49
  50 void pa_x11_set_prop(xcb_connection_t *xcb, int screen, const char *name, const char *data) {
  51     xcb_screen_t *xs;
  52     xcb_atom_t a;
  53
  54     pa_assert(xcb);
  55     pa_assert(name);
  56     pa_assert(data);
  57
  58     if ((xs = screen_of_display(xcb, screen))) {
  59         a = xcb_atom_get(xcb, name);
  60         xcb_change_property(xcb, XCB_PROP_MODE_REPLACE, xs->root, a, STRING, PA_XCB_FORMAT, (int) strlen(data), (const void*) data);
  61     }
  62 }
  63
  64 void pa_x11_del_prop(xcb_connection_t *xcb, int screen, const char *name) {
  65     xcb_screen_t *xs;
  66     xcb_atom_t a;
  67
  68     pa_assert(xcb);
  69     pa_assert(name);
  70
  71     if ((xs = screen_of_display(xcb, screen))) {
  72         a = xcb_atom_get(xcb, name);
  73         xcb_delete_property(xcb, xs->root, a);
  74     }
  75 }
  76
  77 char* pa_x11_get_prop(xcb_connection_t *xcb, int screen, const char *name, char *p, size_t l) {
  78     char *ret = NULL;
  79     int len;
  80     xcb_get_property_cookie_t req;
  81     xcb_get_property_reply_t* prop = NULL;
  82     xcb_screen_t *xs;
  83     xcb_atom_t a;
  84
  85     pa_assert(xcb);
  86     pa_assert(name);
  87     pa_assert(p);
  88
  89
  90     xs = screen_of_display(xcb, screen);
  91     /*
  92      * Also try and get the settings from the first screen.
  93      * This allows for e.g. a Media Center to run on screen 1 (e.g. HDMI) and have
  94      * different defaults (e.g. prefer the HDMI sink) than the primary screen 0
  95      * which uses the Internal Audio sink.
  96      */
  97     if (!xs && 0 != screen)
  98         xs = screen_of_display(xcb, 0);
  99
 100     if (xs) {
 101         a = xcb_atom_get(xcb, name);
 102
 103         req = xcb_get_property(xcb, 0, xs->root, a, STRING, 0, (uint32_t)(l-1));
 104         prop = xcb_get_property_reply(xcb, req, NULL);
 105
 106         if (!prop)
 107             goto finish;
 108
 109         if (PA_XCB_FORMAT != prop->format)
 110             goto finish;
 111
 112         len = xcb_get_property_value_length(prop);
 113         if (len < 1 || len >= (int)l)
 114             goto finish;
 115
 116         memcpy(p, xcb_get_property_value(prop), len);
 117         p[len] = 0;
 118
 119         ret = p;
 120     }
 121
 122 finish:
 123
 124     if (prop)
 125         free(prop);
 126
 127     return ret;
 128 }