/* * lib/cache.c Caching Module * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation version 2.1 * of the License. * * Copyright (c) 2003-2012 Thomas Graf */ /** * @ingroup cache_mngt * @defgroup cache Cache * * @code * Cache Management | | Type Specific Cache Operations * * | | +----------------+ +------------+ * | request update | | msg_parser | * | | +----------------+ +------------+ * +- - - - -^- - - - - - - -^- -|- - - - * nl_cache_update: | | | | * 1) --------- co_request_update ------+ | | * | | | * 2) destroy old cache +----------- pp_cb ---------|---+ * | | | * 3) ---------- nl_recvmsgs ----------+ +- cb_valid -+ * +--------------+ | | | | * | nl_cache_add |<-----+ + - - -v- -|- - - - - - - - - - - * +--------------+ | | +-------------+ * | nl_recvmsgs | * | | +-----|-^-----+ * +---v-|---+ * | | | nl_recv | * +---------+ * | | Core Netlink * @endcode * * Related sections in the development guide: * - @core_doc{core_cache, Caching System} * * @{ * * Header * ------ * ~~~~{.c} * #include * ~~~~ */ #include #include #include #include #include #include /** * @name Access Functions * @{ */ /** * Return the number of items in the cache * @arg cache cache handle */ int nl_cache_nitems(struct nl_cache *cache) { return cache->c_nitems; } /** * Return the number of items matching a filter in the cache * @arg cache Cache object. * @arg filter Filter object. */ int nl_cache_nitems_filter(struct nl_cache *cache, struct nl_object *filter) { struct nl_object *obj; int nitems = 0; if (cache->c_ops == NULL) BUG(); nl_list_for_each_entry(obj, &cache->c_items, ce_list) { if (filter && !nl_object_match_filter(obj, filter)) continue; nitems++; } return nitems; } /** * Returns \b true if the cache is empty. * @arg cache Cache to check * @return \a true if the cache is empty, otherwise \b false is returned. */ int nl_cache_is_empty(struct nl_cache *cache) { return nl_list_empty(&cache->c_items); } /** * Return the operations set of the cache * @arg cache cache handle */ struct nl_cache_ops *nl_cache_get_ops(struct nl_cache *cache) { return cache->c_ops; } /** * Return the first element in the cache * @arg cache cache handle */ struct nl_object *nl_cache_get_first(struct nl_cache *cache) { if (nl_list_empty(&cache->c_items)) return NULL; return nl_list_entry(cache->c_items.next, struct nl_object, ce_list); } /** * Return the last element in the cache * @arg cache cache handle */ struct nl_object *nl_cache_get_last(struct nl_cache *cache) { if (nl_list_empty(&cache->c_items)) return NULL; return nl_list_entry(cache->c_items.prev, struct nl_object, ce_list); } /** * Return the next element in the cache * @arg obj current object */ struct nl_object *nl_cache_get_next(struct nl_object *obj) { if (nl_list_at_tail(obj, &obj->ce_cache->c_items, ce_list)) return NULL; else return nl_list_entry(obj->ce_list.next, struct nl_object, ce_list); } /** * Return the previous element in the cache * @arg obj current object */ struct nl_object *nl_cache_get_prev(struct nl_object *obj) { if (nl_list_at_head(obj, &obj->ce_cache->c_items, ce_list)) return NULL; else return nl_list_entry(obj->ce_list.prev, struct nl_object, ce_list); } /** @} */ /** * @name Cache Allocation/Deletion * @{ */ /** * Allocate new cache * @arg ops Cache operations * * Allocate and initialize a new cache based on the cache operations * provided. * * @return Allocated cache or NULL if allocation failed. */ struct nl_cache *nl_cache_alloc(struct nl_cache_ops *ops) { struct nl_cache *cache; cache = calloc(1, sizeof(*cache)); if (!cache) return NULL; nl_init_list_head(&cache->c_items); cache->c_ops = ops; cache->c_flags |= ops->co_flags; cache->c_refcnt = 1; /* * If object type provides a hash keygen * functions, allocate a hash table for the * cache objects for faster lookups */ if (ops->co_obj_ops->oo_keygen) { int hashtable_size; if (ops->co_hash_size) hashtable_size = ops->co_hash_size; else hashtable_size = NL_MAX_HASH_ENTRIES; cache->hashtable = nl_hash_table_alloc(hashtable_size); } NL_DBG(2, "Allocated cache %p <%s>.\n", cache, nl_cache_name(cache)); return cache; } /** * Allocate new cache and fill it * @arg ops Cache operations * @arg sock Netlink socket * @arg result Result pointer * * Allocate new cache and fill it. Equivalent to calling: * @code * cache = nl_cache_alloc(ops); * nl_cache_refill(sock, cache); * @endcode * * @see nl_cache_alloc * * @return 0 on success or a negative error code. */ int nl_cache_alloc_and_fill(struct nl_cache_ops *ops, struct nl_sock *sock, struct nl_cache **result) { struct nl_cache *cache; int err; if (!(cache = nl_cache_alloc(ops))) return -NLE_NOMEM; if (sock && (err = nl_cache_refill(sock, cache)) < 0) { nl_cache_free(cache); return err; } *result = cache; return 0; } /** * Allocate new cache based on type name * @arg kind Name of cache type * @arg result Result pointer * * Lookup cache ops via nl_cache_ops_lookup() and allocate the cache * by calling nl_cache_alloc(). Stores the allocated cache in the * result pointer provided. * * @see nl_cache_alloc * * @return 0 on success or a negative error code. */ int nl_cache_alloc_name(const char *kind, struct nl_cache **result) { struct nl_cache_ops *ops; struct nl_cache *cache; ops = nl_cache_ops_lookup_safe(kind); if (!ops) return -NLE_NOCACHE; cache = nl_cache_alloc(ops); nl_cache_ops_put(ops); if (!cache) return -NLE_NOMEM; *result = cache; return 0; } /** * Allocate new cache containing a subset of an existing cache * @arg orig Original cache to base new cache on * @arg filter Filter defining the subset to be filled into the new cache * * Allocates a new cache matching the type of the cache specified by * \p orig. Iterates over the \p orig cache applying the specified * \p filter and copies all objects that match to the new cache. * * The copied objects are clones but do not contain a reference to each * other. Later modifications to objects in the original cache will * not affect objects in the new cache. * * @return A newly allocated cache or NULL. */ struct nl_cache *nl_cache_subset(struct nl_cache *orig, struct nl_object *filter) { struct nl_cache *cache; struct nl_object *obj; if (!filter) BUG(); cache = nl_cache_alloc(orig->c_ops); if (!cache) return NULL; NL_DBG(2, "Filling subset of cache %p <%s> with filter %p into %p\n", orig, nl_cache_name(orig), filter, cache); nl_list_for_each_entry(obj, &orig->c_items, ce_list) { if (!nl_object_match_filter(obj, filter)) continue; nl_cache_add(cache, obj); } return cache; } /** * Allocate new cache and copy the contents of an existing cache * @arg cache Original cache to base new cache on * * Allocates a new cache matching the type of the cache specified by * \p cache. Iterates over the \p cache cache and copies all objects * to the new cache. * * The copied objects are clones but do not contain a reference to each * other. Later modifications to objects in the original cache will * not affect objects in the new cache. * * @return A newly allocated cache or NULL. */ struct nl_cache *nl_cache_clone(struct nl_cache *cache) { struct nl_cache_ops *ops = nl_cache_get_ops(cache); struct nl_cache *clone; struct nl_object *obj; clone = nl_cache_alloc(ops); if (!clone) return NULL; NL_DBG(2, "Cloning %p into %p\n", cache, clone); nl_list_for_each_entry(obj, &cache->c_items, ce_list) nl_cache_add(clone, obj); return clone; } /** * Remove all objects of a cache. * @arg cache Cache to clear * * The objects are unliked/removed from the cache by calling * nl_cache_remove() on each object in the cache. If any of the objects * to not contain any further references to them, those objects will * be freed. * * Unlike with nl_cache_free(), the cache is not freed just emptied. */ void nl_cache_clear(struct nl_cache *cache) { struct nl_object *obj, *tmp; NL_DBG(2, "Clearing cache %p <%s>...\n", cache, nl_cache_name(cache)); nl_list_for_each_entry_safe(obj, tmp, &cache->c_items, ce_list) nl_cache_remove(obj); } static void __nl_cache_free(struct nl_cache *cache) { nl_cache_clear(cache); if (cache->hashtable) nl_hash_table_free(cache->hashtable); NL_DBG(2, "Freeing cache %p <%s>...\n", cache, nl_cache_name(cache)); free(cache); } /** * Increase reference counter of cache * @arg cache Cache */ void nl_cache_get(struct nl_cache *cache) { cache->c_refcnt++; NL_DBG(3, "Incremented cache %p <%s> reference count to %d\n", cache, nl_cache_name(cache), cache->c_refcnt); } /** * Free a cache. * @arg cache Cache to free. * * Calls nl_cache_clear() to remove all objects associated with the * cache and frees the cache afterwards. * * @see nl_cache_clear() */ void nl_cache_free(struct nl_cache *cache) { if (!cache) return; cache->c_refcnt--; NL_DBG(3, "Decremented cache %p <%s> reference count, %d remaining\n", cache, nl_cache_name(cache), cache->c_refcnt); if (cache->c_refcnt <= 0) __nl_cache_free(cache); } void nl_cache_put(struct nl_cache *cache) { return nl_cache_free(cache); } /** @} */ /** * @name Cache Modifications * @{ */ static int __cache_add(struct nl_cache *cache, struct nl_object *obj) { int ret; obj->ce_cache = cache; if (cache->hashtable) { ret = nl_hash_table_add(cache->hashtable, obj); if (ret < 0) { obj->ce_cache = NULL; return ret; } } nl_list_add_tail(&obj->ce_list, &cache->c_items); cache->c_nitems++; NL_DBG(3, "Added object %p to cache %p <%s>, nitems %d\n", obj, cache, nl_cache_name(cache), cache->c_nitems); return 0; } /** * Add object to cache. * @arg cache Cache * @arg obj Object to be added to the cache * * Adds the object \p obj to the specified \p cache. In case the object * is already associated with another cache, the object is cloned before * adding it to the cache. In this case, the sole reference to the object * will be the one of the cache. Therefore clearing/freeing the cache * will result in the object being freed again. * * If the object has not been associated with a cache yet, the reference * counter of the object is incremented to account for the additional * reference. * * The type of the object and cache must match, otherwise an error is * returned (-NLE_OBJ_MISMATCH). * * @see nl_cache_move() * * @return 0 or a negative error code. */ int nl_cache_add(struct nl_cache *cache, struct nl_object *obj) { struct nl_object *new; int ret = 0; if (cache->c_ops->co_obj_ops != obj->ce_ops) return -NLE_OBJ_MISMATCH; if (!nl_list_empty(&obj->ce_list)) { NL_DBG(3, "Object %p already in cache, cloning new object\n", obj); new = nl_object_clone(obj); if (!new) return -NLE_NOMEM; } else { nl_object_get(obj); new = obj; } ret = __cache_add(cache, new); if (ret < 0) nl_object_put(new); return ret; } /** * Move object from one cache to another * @arg cache Cache to move object to. * @arg obj Object subject to be moved * * Removes the the specified object \p obj from its associated cache * and moves it to another cache. * * If the object is not associated with a cache, the function behaves * just like nl_cache_add(). * * The type of the object and cache must match, otherwise an error is * returned (-NLE_OBJ_MISMATCH). * * @see nl_cache_add() * * @return 0 on success or a negative error code. */ int nl_cache_move(struct nl_cache *cache, struct nl_object *obj) { if (cache->c_ops->co_obj_ops != obj->ce_ops) return -NLE_OBJ_MISMATCH; NL_DBG(3, "Moving object %p from cache %p to cache %p\n", obj, obj->ce_cache, cache); /* Acquire reference, if already in a cache this will be * reverted during removal */ nl_object_get(obj); if (!nl_list_empty(&obj->ce_list)) nl_cache_remove(obj); return __cache_add(cache, obj); } /** * Remove object from cache. * @arg obj Object to remove from cache * * Removes the object \c obj from the cache it is associated with. The * reference counter of the object will be decremented. If the reference * to the object was the only one remaining, the object will be freed. * * If no cache is associated with the object, this function is a NOP. */ void nl_cache_remove(struct nl_object *obj) { int ret; struct nl_cache *cache = obj->ce_cache; if (cache == NULL) return; if (cache->hashtable) { ret = nl_hash_table_del(cache->hashtable, obj); if (ret < 0) NL_DBG(2, "Failed to delete %p from cache %p <%s>.\n", obj, cache, nl_cache_name(cache)); } nl_list_del(&obj->ce_list); obj->ce_cache = NULL; nl_object_put(obj); cache->c_nitems--; NL_DBG(2, "Deleted object %p from cache %p <%s>.\n", obj, cache, nl_cache_name(cache)); } /** @} */ /** * @name Synchronization * @{ */ /** * Set synchronization arg1 of cache * @arg cache Cache * @arg arg argument * * Synchronization arguments are used to specify filters when * requesting dumps from the kernel. */ void nl_cache_set_arg1(struct nl_cache *cache, int arg) { cache->c_iarg1 = arg; } /** * Set synchronization arg2 of cache * @arg cache Cache * @arg arg argument * * Synchronization arguments are used to specify filters when * requesting dumps from the kernel. */ void nl_cache_set_arg2(struct nl_cache *cache, int arg) { cache->c_iarg2 = arg; } /** * Set cache flags * @arg cache Cache * @arg flags Flags */ void nl_cache_set_flags(struct nl_cache *cache, unsigned int flags) { cache->c_flags |= flags; } /** * Invoke the request-update operation * @arg sk Netlink socket. * @arg cache Cache * * This function causes the \e request-update function of the cache * operations to be invoked. This usually causes a dump request to * be sent over the netlink socket which triggers the kernel to dump * all objects of a specific type to be dumped onto the netlink * socket for pickup. * * The behaviour of this function depends on the implemenation of * the \e request_update function of each individual type of cache. * * This function will not have any effects on the cache (unless the * request_update implementation of the cache operations does so). * * Use nl_cache_pickup() to pick-up (read) the objects from the socket * and fill them into the cache. * * @see nl_cache_pickup(), nl_cache_resync() * * @return 0 on success or a negative error code. */ static int nl_cache_request_full_dump(struct nl_sock *sk, struct nl_cache *cache) { if (cache->c_ops->co_request_update == NULL) return -NLE_OPNOTSUPP; NL_DBG(2, "Requesting update from kernel for cache %p <%s>\n", cache, nl_cache_name(cache)); return cache->c_ops->co_request_update(cache, sk); } /** @cond SKIP */ struct update_xdata { struct nl_cache_ops *ops; struct nl_parser_param *params; }; static int update_msg_parser(struct nl_msg *msg, void *arg) { struct update_xdata *x = arg; int ret = 0; ret = nl_cache_parse(x->ops, &msg->nm_src, msg->nm_nlh, x->params); if (ret == -NLE_EXIST) return NL_SKIP; else return ret; } /** @endcond */ /** * Pick-up a netlink request-update with your own parser * @arg sk Netlink socket * @arg cache Cache * @arg param Parser parameters */ static int __cache_pickup(struct nl_sock *sk, struct nl_cache *cache, struct nl_parser_param *param) { int err; struct nl_cb *cb; struct update_xdata x = { .ops = cache->c_ops, .params = param, }; NL_DBG(2, "Picking up answer for cache %p <%s>\n", cache, nl_cache_name(cache)); cb = nl_cb_clone(sk->s_cb); if (cb == NULL) return -NLE_NOMEM; nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, update_msg_parser, &x); err = nl_recvmsgs(sk, cb); if (err < 0) NL_DBG(2, "While picking up for %p <%s>, recvmsgs() returned %d: %s\n", cache, nl_cache_name(cache), err, nl_geterror(err)); nl_cb_put(cb); return err; } static int pickup_cb(struct nl_object *c, struct nl_parser_param *p) { struct nl_cache *cache = (struct nl_cache *)p->pp_arg; struct nl_object *old; old = nl_cache_search(cache, c); if (old) { if (nl_object_update(old, c) == 0) { nl_object_put(old); return 0; } nl_cache_remove(old); nl_object_put(old); } return nl_cache_add(cache, c); } /** * Pickup a netlink dump response and put it into a cache. * @arg sk Netlink socket. * @arg cache Cache to put items into. * * Waits for netlink messages to arrive, parses them and puts them into * the specified cache. If an old object with same key attributes is * present in the cache, it is replaced with the new object. * If the old object type supports an update operation, an update is * attempted before a replace. * * @return 0 on success or a negative error code. */ int nl_cache_pickup(struct nl_sock *sk, struct nl_cache *cache) { struct nl_parser_param p = { .pp_cb = pickup_cb, .pp_arg = cache, }; return __cache_pickup(sk, cache, &p); } static int cache_include(struct nl_cache *cache, struct nl_object *obj, struct nl_msgtype *type, change_func_t cb, void *data) { struct nl_object *old; switch (type->mt_act) { case NL_ACT_NEW: case NL_ACT_DEL: old = nl_cache_search(cache, obj); if (old) { /* * Some objects types might support merging the new * object with the old existing cache object. * Handle them first. */ if (nl_object_update(old, obj) == 0) { if (cb) cb(cache, old, NL_ACT_CHANGE, data); nl_object_put(old); return 0; } nl_cache_remove(old); if (type->mt_act == NL_ACT_DEL) { if (cb) cb(cache, old, NL_ACT_DEL, data); nl_object_put(old); } } if (type->mt_act == NL_ACT_NEW) { nl_cache_move(cache, obj); if (old == NULL && cb) cb(cache, obj, NL_ACT_NEW, data); else if (old) { if (nl_object_diff(old, obj) && cb) cb(cache, obj, NL_ACT_CHANGE, data); nl_object_put(old); } } break; default: NL_DBG(2, "Unknown action associated to object %p\n", obj); return 0; } return 0; } int nl_cache_include(struct nl_cache *cache, struct nl_object *obj, change_func_t change_cb, void *data) { struct nl_cache_ops *ops = cache->c_ops; int i; if (ops->co_obj_ops != obj->ce_ops) return -NLE_OBJ_MISMATCH; for (i = 0; ops->co_msgtypes[i].mt_id >= 0; i++) if (ops->co_msgtypes[i].mt_id == obj->ce_msgtype) return cache_include(cache, obj, &ops->co_msgtypes[i], change_cb, data); NL_DBG(3, "Object %p does not seem to belong to cache %p <%s>\n", obj, cache, nl_cache_name(cache)); return -NLE_MSGTYPE_NOSUPPORT; } static int resync_cb(struct nl_object *c, struct nl_parser_param *p) { struct nl_cache_assoc *ca = p->pp_arg; return nl_cache_include(ca->ca_cache, c, ca->ca_change, ca->ca_change_data); } int nl_cache_resync(struct nl_sock *sk, struct nl_cache *cache, change_func_t change_cb, void *data) { struct nl_object *obj, *next; struct nl_af_group *grp; struct nl_cache_assoc ca = { .ca_cache = cache, .ca_change = change_cb, .ca_change_data = data, }; struct nl_parser_param p = { .pp_cb = resync_cb, .pp_arg = &ca, }; int err; NL_DBG(1, "Resyncing cache %p <%s>...\n", cache, nl_cache_name(cache)); /* Mark all objects so we can see if some of them are obsolete */ nl_cache_mark_all(cache); grp = cache->c_ops->co_groups; do { if (grp && grp->ag_group && (cache->c_flags & NL_CACHE_AF_ITER)) nl_cache_set_arg1(cache, grp->ag_family); restart: err = nl_cache_request_full_dump(sk, cache); if (err < 0) goto errout; err = __cache_pickup(sk, cache, &p); if (err == -NLE_DUMP_INTR) goto restart; else if (err < 0) goto errout; if (grp) grp++; } while (grp && grp->ag_group && (cache->c_flags & NL_CACHE_AF_ITER)); nl_list_for_each_entry_safe(obj, next, &cache->c_items, ce_list) { if (nl_object_is_marked(obj)) { nl_object_get(obj); nl_cache_remove(obj); if (change_cb) change_cb(cache, obj, NL_ACT_DEL, data); nl_object_put(obj); } } NL_DBG(1, "Finished resyncing %p <%s>\n", cache, nl_cache_name(cache)); err = 0; errout: return err; } /** @} */ /** * @name Parsing * @{ */ /** @cond SKIP */ int nl_cache_parse(struct nl_cache_ops *ops, struct sockaddr_nl *who, struct nlmsghdr *nlh, struct nl_parser_param *params) { int i, err; if (!nlmsg_valid_hdr(nlh, ops->co_hdrsize)) return -NLE_MSG_TOOSHORT; for (i = 0; ops->co_msgtypes[i].mt_id >= 0; i++) { if (ops->co_msgtypes[i].mt_id == nlh->nlmsg_type) { err = ops->co_msg_parser(ops, who, nlh, params); if (err != -NLE_OPNOTSUPP) goto errout; } } err = -NLE_MSGTYPE_NOSUPPORT; errout: return err; } /** @endcond */ /** * Parse a netlink message and add it to the cache. * @arg cache cache to add element to * @arg msg netlink message * * Parses a netlink message by calling the cache specific message parser * and adds the new element to the cache. If an old object with same key * attributes is present in the cache, it is replaced with the new object. * If the old object type supports an update operation, an update is * attempted before a replace. * * @return 0 or a negative error code. */ int nl_cache_parse_and_add(struct nl_cache *cache, struct nl_msg *msg) { struct nl_parser_param p = { .pp_cb = pickup_cb, .pp_arg = cache, }; return nl_cache_parse(cache->c_ops, NULL, nlmsg_hdr(msg), &p); } /** * (Re)fill a cache with the contents in the kernel. * @arg sk Netlink socket. * @arg cache cache to update * * Clears the specified cache and fills it with the current state in * the kernel. * * @return 0 or a negative error code. */ int nl_cache_refill(struct nl_sock *sk, struct nl_cache *cache) { struct nl_af_group *grp; int err; nl_cache_clear(cache); grp = cache->c_ops->co_groups; do { if (grp && grp->ag_group && (cache->c_flags & NL_CACHE_AF_ITER)) nl_cache_set_arg1(cache, grp->ag_family); restart: err = nl_cache_request_full_dump(sk, cache); if (err < 0) return err; NL_DBG(2, "Updating cache %p <%s> for family %u, request sent, waiting for reply\n", cache, nl_cache_name(cache), grp ? grp->ag_family : AF_UNSPEC); err = nl_cache_pickup(sk, cache); if (err == -NLE_DUMP_INTR) { NL_DBG(2, "Dump interrupted, restarting!\n"); goto restart; } else if (err < 0) break; if (grp) grp++; } while (grp && grp->ag_group && (cache->c_flags & NL_CACHE_AF_ITER)); return err; } /** @} */ /** * @name Utillities * @{ */ static struct nl_object *__cache_fast_lookup(struct nl_cache *cache, struct nl_object *needle) { struct nl_object *obj; obj = nl_hash_table_lookup(cache->hashtable, needle); if (obj) { nl_object_get(obj); return obj; } return NULL; } /** * Search object in cache * @arg cache Cache * @arg needle Object to look for. * * Searches the cache for an object which matches the object \p needle. * The function nl_object_identical() is used to determine if the * objects match. If a matching object is found, the reference counter * is incremented and the object is returned. * * Therefore, if an object is returned, the reference to the object * must be returned by calling nl_object_put() after usage. * * @return Reference to object or NULL if not found. */ struct nl_object *nl_cache_search(struct nl_cache *cache, struct nl_object *needle) { struct nl_object *obj; if (cache->hashtable) return __cache_fast_lookup(cache, needle); nl_list_for_each_entry(obj, &cache->c_items, ce_list) { if (nl_object_identical(obj, needle)) { nl_object_get(obj); return obj; } } return NULL; } /** * Find object in cache * @arg cache Cache * @arg filter object acting as a filter * * Searches the cache for an object which matches the object filter. * If the filter attributes matches the object type id attributes, * and the cache supports hash lookups, a faster hashtable lookup * is used to return the object. Else, function nl_object_match_filter() is * used to determine if the objects match. If a matching object is * found, the reference counter is incremented and the object is returned. * * Therefore, if an object is returned, the reference to the object * must be returned by calling nl_object_put() after usage. * * @return Reference to object or NULL if not found. */ struct nl_object *nl_cache_find(struct nl_cache *cache, struct nl_object *filter) { struct nl_object *obj; if (cache->c_ops == NULL) BUG(); if ((nl_object_get_id_attrs(filter) == filter->ce_mask) && cache->hashtable) return __cache_fast_lookup(cache, filter); nl_list_for_each_entry(obj, &cache->c_items, ce_list) { if (nl_object_match_filter(obj, filter)) { nl_object_get(obj); return obj; } } return NULL; } /** * Mark all objects of a cache * @arg cache Cache * * Marks all objects of a cache by calling nl_object_mark() on each * object associated with the cache. */ void nl_cache_mark_all(struct nl_cache *cache) { struct nl_object *obj; NL_DBG(2, "Marking all objects in cache %p <%s>\n", cache, nl_cache_name(cache)); nl_list_for_each_entry(obj, &cache->c_items, ce_list) nl_object_mark(obj); } /** @} */ /** * @name Dumping * @{ */ /** * Dump all elements of a cache. * @arg cache cache to dump * @arg params dumping parameters * * Dumps all elements of the \a cache to the file descriptor \a fd. */ void nl_cache_dump(struct nl_cache *cache, struct nl_dump_params *params) { nl_cache_dump_filter(cache, params, NULL); } /** * Dump all elements of a cache (filtered). * @arg cache cache to dump * @arg params dumping parameters (optional) * @arg filter filter object * * Dumps all elements of the \a cache to the file descriptor \a fd * given they match the given filter \a filter. */ void nl_cache_dump_filter(struct nl_cache *cache, struct nl_dump_params *params, struct nl_object *filter) { int type = params ? params->dp_type : NL_DUMP_DETAILS; struct nl_object_ops *ops; struct nl_object *obj; NL_DBG(2, "Dumping cache %p <%s> with filter %p\n", cache, nl_cache_name(cache), filter); if (type > NL_DUMP_MAX || type < 0) BUG(); if (cache->c_ops == NULL) BUG(); ops = cache->c_ops->co_obj_ops; if (!ops->oo_dump[type]) return; if (params->dp_buf) memset(params->dp_buf, 0, params->dp_buflen); nl_list_for_each_entry(obj, &cache->c_items, ce_list) { if (filter && !nl_object_match_filter(obj, filter)) continue; NL_DBG(4, "Dumping object %p...\n", obj); dump_from_ops(obj, params); } } /** @} */ /** * @name Iterators * @{ */ /** * Call a callback on each element of the cache. * @arg cache cache to iterate on * @arg cb callback function * @arg arg argument passed to callback function * * Calls a callback function \a cb on each element of the \a cache. * The argument \a arg is passed on the callback function. */ void nl_cache_foreach(struct nl_cache *cache, void (*cb)(struct nl_object *, void *), void *arg) { nl_cache_foreach_filter(cache, NULL, cb, arg); } /** * Call a callback on each element of the cache (filtered). * @arg cache cache to iterate on * @arg filter filter object * @arg cb callback function * @arg arg argument passed to callback function * * Calls a callback function \a cb on each element of the \a cache * that matches the \a filter. The argument \a arg is passed on * to the callback function. */ void nl_cache_foreach_filter(struct nl_cache *cache, struct nl_object *filter, void (*cb)(struct nl_object *, void *), void *arg) { struct nl_object *obj, *tmp; if (cache->c_ops == NULL) BUG(); nl_list_for_each_entry_safe(obj, tmp, &cache->c_items, ce_list) { if (filter) { int diff = nl_object_match_filter(obj, filter); NL_DBG(3, "%p<->%p object difference: %x\n", obj, filter, diff); if (!diff) continue; } /* Caller may hold obj for a long time */ nl_object_get(obj); cb(obj, arg); nl_object_put(obj); } } /** @} */ /** @} */