1 /* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp.
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:
10 * The above copyright notice and this permission notice shall be included in
11 * all copies or substantial portions of the Software.
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.
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.
26 /* A cache for QueryExtension results. */
35 typedef struct lazyreply {
36 enum lazy_reply_tag tag;
38 xcb_query_extension_cookie_t cookie;
39 xcb_query_extension_reply_t *reply;
43 static lazyreply *get_index(xcb_connection_t *c, int idx)
45 if(idx > c->ext.extensions_size)
47 int new_size = idx << 1;
48 lazyreply *new_extensions = realloc(c->ext.extensions, sizeof(lazyreply) * new_size);
51 memset(new_extensions + c->ext.extensions_size, 0, sizeof(lazyreply) * (new_size - c->ext.extensions_size));
52 c->ext.extensions = new_extensions;
53 c->ext.extensions_size = new_size;
55 return c->ext.extensions + idx - 1;
58 static lazyreply *get_lazyreply(xcb_connection_t *c, xcb_extension_t *ext)
60 static pthread_mutex_t global_lock = PTHREAD_MUTEX_INITIALIZER;
61 static int next_global_id;
65 pthread_mutex_lock(&global_lock);
67 ext->global_id = ++next_global_id;
68 pthread_mutex_unlock(&global_lock);
70 data = get_index(c, ext->global_id);
71 if(data && data->tag == LAZY_NONE)
73 /* cache miss: query the server */
74 data->tag = LAZY_COOKIE;
75 data->value.cookie = xcb_query_extension(c, strlen(ext->name), ext->name);
80 /* Public interface */
82 /* Do not free the returned xcb_query_extension_reply_t - on return, it's aliased
84 const xcb_query_extension_reply_t *xcb_get_extension_data(xcb_connection_t *c, xcb_extension_t *ext)
90 pthread_mutex_lock(&c->ext.lock);
91 data = get_lazyreply(c, ext);
92 if(data && data->tag == LAZY_COOKIE)
94 data->tag = LAZY_FORCED;
95 data->value.reply = xcb_query_extension_reply(c, data->value.cookie, 0);
97 pthread_mutex_unlock(&c->ext.lock);
99 return data ? data->value.reply : 0;
102 void xcb_prefetch_extension_data(xcb_connection_t *c, xcb_extension_t *ext)
106 pthread_mutex_lock(&c->ext.lock);
107 get_lazyreply(c, ext);
108 pthread_mutex_unlock(&c->ext.lock);
111 /* Private interface */
113 int _xcb_ext_init(xcb_connection_t *c)
115 if(pthread_mutex_init(&c->ext.lock, 0))
120 void _xcb_ext_destroy(xcb_connection_t *c)
122 pthread_mutex_destroy(&c->ext.lock);
123 while(c->ext.extensions_size-- > 0)
124 if(c->ext.extensions[c->ext.extensions_size].tag == LAZY_FORCED)
125 free(c->ext.extensions[c->ext.extensions_size].value.reply);
126 free(c->ext.extensions);