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
  34 #define PA_XCB_FORMAT 8
  35
  36 static xcb_screen_t *screen_of_display(xcb_connection_t *xcb, int screen) {
  37     const xcb_setup_t *s;
  38     xcb_screen_iterator_t iter;
  39
  40     if ((s = xcb_get_setup(xcb))) {
  41         iter = xcb_setup_roots_iterator(s);
  42         for (; iter.rem; --screen, xcb_screen_next(&iter))
  43             if (0 == screen)
  44                 return iter.data;
  45     }
  46     return NULL;
  47 }
  48
  49 void pa_x11_set_prop(xcb_connection_t *xcb, int screen, const char *name, const char *data) {
  50     xcb_screen_t *xs;
  51     xcb_intern_atom_reply_t *reply;
  52
  53     pa_assert(xcb);
  54     pa_assert(name);
  55     pa_assert(data);
  56
  57     if ((xs = screen_of_display(xcb, screen))) {
  58         reply = xcb_intern_atom_reply(xcb,
  59                                       xcb_intern_atom(xcb, 0, strlen(name), name),
  60                                       NULL);
  61
  62         if (reply) {
  63             xcb_change_property(xcb, XCB_PROP_MODE_REPLACE, xs->root, reply->atom,
  64                                 XCB_ATOM_STRING, PA_XCB_FORMAT,
  65                                 (int) strlen(data), (const void*) data);
  66
  67             free(reply);
  68         }
  69     }
  70 }
  71
  72 void pa_x11_del_prop(xcb_connection_t *xcb, int screen, const char *name) {
  73     xcb_screen_t *xs;
  74     xcb_intern_atom_reply_t *reply;
  75
  76     pa_assert(xcb);
  77     pa_assert(name);
  78
  79     if ((xs = screen_of_display(xcb, screen))) {
  80         reply = xcb_intern_atom_reply(xcb,
  81                                       xcb_intern_atom(xcb, 0, strlen(name), name),
  82                                       NULL);
  83
  84         if (reply) {
  85             xcb_delete_property(xcb, xs->root, reply->atom);
  86             free(reply);
  87         }
  88     }
  89 }
  90
  91 char* pa_x11_get_prop(xcb_connection_t *xcb, int screen, const char *name, char *p, size_t l) {
  92     char *ret = NULL;
  93     int len;
  94     xcb_get_property_cookie_t req;
  95     xcb_get_property_reply_t* prop = NULL;
  96     xcb_screen_t *xs;
  97     xcb_intern_atom_reply_t *reply;
  98
  99     pa_assert(xcb);
 100     pa_assert(name);
 101     pa_assert(p);
 102
 103
 104     xs = screen_of_display(xcb, screen);
 105     /*
 106      * Also try and get the settings from the first screen.
 107      * This allows for e.g. a Media Center to run on screen 1 (e.g. HDMI) and have
 108      * different defaults (e.g. prefer the HDMI sink) than the primary screen 0
 109      * which uses the Internal Audio sink.
 110      */
 111     if (!xs && 0 != screen)
 112         xs = screen_of_display(xcb, 0);
 113
 114     if (xs) {
 115         reply = xcb_intern_atom_reply(xcb,
 116                                       xcb_intern_atom(xcb, 0, strlen(name), name),
 117                                       NULL);
 118
 119         if (!reply)
 120             goto finish;
 121
 122         req = xcb_get_property(xcb, 0, xs->root, reply->atom, XCB_ATOM_STRING, 0, (uint32_t)(l-1));
 123         free(reply);
 124         prop = xcb_get_property_reply(xcb, req, NULL);
 125
 126         if (!prop)
 127             goto finish;
 128
 129         if (PA_XCB_FORMAT != prop->format)
 130             goto finish;
 131
 132         len = xcb_get_property_value_length(prop);
 133         if (len < 1 || len >= (int)l)
 134             goto finish;
 135
 136         memcpy(p, xcb_get_property_value(prop), len);
 137         p[len] = 0;
 138
 139         ret = p;
 140     }
 141
 142 finish:
 143
 144     if (prop)
 145         free(prop);
 146
 147     return ret;
 148 }