/* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * Except as contained in this notice, the names of the authors or their * institutions shall not be used in advertising or otherwise to promote the * sale, use or other dealings in this Software without prior written * authorization from the authors. */ /* A cache for QueryExtension results. */ #include <stdlib.h> #include <string.h> #include "xcb.h" #include "xcbext.h" #include "xcbint.h" typedef struct lazyreply { enum lazy_reply_tag tag; union { xcb_query_extension_cookie_t cookie; xcb_query_extension_reply_t *reply; } value; } lazyreply; static lazyreply *get_index(xcb_connection_t *c, int idx) { if(idx > c->ext.extensions_size) { int new_size = idx << 1; lazyreply *new_extensions = realloc(c->ext.extensions, sizeof(lazyreply) * new_size); if(!new_extensions) return 0; memset(new_extensions + c->ext.extensions_size, 0, sizeof(lazyreply) * (new_size - c->ext.extensions_size)); c->ext.extensions = new_extensions; c->ext.extensions_size = new_size; } return c->ext.extensions + idx - 1; } static lazyreply *get_lazyreply(xcb_connection_t *c, xcb_extension_t *ext) { static pthread_mutex_t global_lock = PTHREAD_MUTEX_INITIALIZER; static int next_global_id; lazyreply *data; pthread_mutex_lock(&global_lock); if(!ext->global_id) ext->global_id = ++next_global_id; pthread_mutex_unlock(&global_lock); data = get_index(c, ext->global_id); if(data && data->tag == LAZY_NONE) { /* cache miss: query the server */ data->tag = LAZY_COOKIE; data->value.cookie = xcb_query_extension(c, strlen(ext->name), ext->name); } return data; } /* Public interface */ /* Do not free the returned xcb_query_extension_reply_t - on return, it's aliased * from the cache. */ const xcb_query_extension_reply_t *xcb_get_extension_data(xcb_connection_t *c, xcb_extension_t *ext) { lazyreply *data; if(c->has_error) return 0; pthread_mutex_lock(&c->ext.lock); data = get_lazyreply(c, ext); if(data && data->tag == LAZY_COOKIE) { data->tag = LAZY_FORCED; data->value.reply = xcb_query_extension_reply(c, data->value.cookie, 0); } pthread_mutex_unlock(&c->ext.lock); return data ? data->value.reply : 0; } void xcb_prefetch_extension_data(xcb_connection_t *c, xcb_extension_t *ext) { if(c->has_error) return; pthread_mutex_lock(&c->ext.lock); get_lazyreply(c, ext); pthread_mutex_unlock(&c->ext.lock); } /* Private interface */ int _xcb_ext_init(xcb_connection_t *c) { if(pthread_mutex_init(&c->ext.lock, 0)) return 0; return 1; } void _xcb_ext_destroy(xcb_connection_t *c) { if (!c->ext.lock) return; /* mutex is not initialised */ pthread_mutex_destroy(&c->ext.lock); while(c->ext.extensions_size-- > 0) if(c->ext.extensions[c->ext.extensions_size].tag == LAZY_FORCED) free(c->ext.extensions[c->ext.extensions_size].value.reply); free(c->ext.extensions); }