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-rw-r--r--package/libs/libnl-tiny/src/cache.c376
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diff --git a/package/libs/libnl-tiny/src/cache.c b/package/libs/libnl-tiny/src/cache.c
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+/*
+ * 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) 2003-2008 Thomas Graf <tgraf@suug.ch>
+ */
+
+/**
+ * @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
+ *
+ * @{
+ */
+
+#include <netlink-local.h>
+#include <netlink/netlink.h>
+#include <netlink/cache.h>
+#include <netlink/object.h>
+#include <netlink/utils.h>
+
+/**
+ * @name Cache Creation/Deletion
+ * @{
+ */
+
+/**
+ * Allocate an empty cache
+ * @arg ops cache operations to base the cache on
+ *
+ * @return A newly allocated and initialized cache.
+ */
+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;
+
+ NL_DBG(2, "Allocated cache %p <%s>.\n", cache, nl_cache_name(cache));
+
+ return cache;
+}
+
+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;
+}
+
+/**
+ * Clear a cache.
+ * @arg cache cache to clear
+ *
+ * Removes all elements of a cache.
+ */
+void nl_cache_clear(struct nl_cache *cache)
+{
+ struct nl_object *obj, *tmp;
+
+ NL_DBG(1, "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);
+}
+
+/**
+ * Free a cache.
+ * @arg cache Cache to free.
+ *
+ * Removes all elements of a cache and frees all memory.
+ *
+ * @note Use this function if you are working with allocated caches.
+ */
+void nl_cache_free(struct nl_cache *cache)
+{
+ if (!cache)
+ return;
+
+ nl_cache_clear(cache);
+ NL_DBG(1, "Freeing cache %p <%s>...\n", cache, nl_cache_name(cache));
+ free(cache);
+}
+
+/** @} */
+
+/**
+ * @name Cache Modifications
+ * @{
+ */
+
+static int __cache_add(struct nl_cache *cache, struct nl_object *obj)
+{
+ obj->ce_cache = cache;
+
+ nl_list_add_tail(&obj->ce_list, &cache->c_items);
+ cache->c_nitems++;
+
+ NL_DBG(1, "Added %p to cache %p <%s>.\n",
+ obj, cache, nl_cache_name(cache));
+
+ return 0;
+}
+
+/**
+ * Add object to a cache.
+ * @arg cache Cache to add object to
+ * @arg obj Object to be added to the cache
+ *
+ * Adds the given object to the specified cache. The object is cloned
+ * if it has been added to another cache already.
+ *
+ * @return 0 or a negative error code.
+ */
+int nl_cache_add(struct nl_cache *cache, struct nl_object *obj)
+{
+ struct nl_object *new;
+
+ if (cache->c_ops->co_obj_ops != obj->ce_ops)
+ return -NLE_OBJ_MISMATCH;
+
+ if (!nl_list_empty(&obj->ce_list)) {
+ new = nl_object_clone(obj);
+ if (!new)
+ return -NLE_NOMEM;
+ } else {
+ nl_object_get(obj);
+ new = obj;
+ }
+
+ return __cache_add(cache, new);
+}
+
+/**
+ * Removes an object from a cache.
+ * @arg obj Object to remove from its cache
+ *
+ * Removes the object \c obj from the cache it is assigned to, since
+ * an object can only be assigned to one cache at a time, the cache
+ * must ne be passed along with it.
+ */
+void nl_cache_remove(struct nl_object *obj)
+{
+ struct nl_cache *cache = obj->ce_cache;
+
+ if (cache == NULL)
+ return;
+
+ nl_list_del(&obj->ce_list);
+ obj->ce_cache = NULL;
+ nl_object_put(obj);
+ cache->c_nitems--;
+
+ NL_DBG(1, "Deleted %p from cache %p <%s>.\n",
+ obj, cache, nl_cache_name(cache));
+}
+
+/** @} */
+
+/**
+ * @name Synchronization
+ * @{
+ */
+
+/**
+ * Request a full dump from the kernel to fill a cache
+ * @arg sk Netlink socket.
+ * @arg cache Cache subjected to be filled.
+ *
+ * Send a dumping request to the kernel causing it to dump all objects
+ * related to the specified cache to the netlink socket.
+ *
+ * Use nl_cache_pickup() to read the objects from the socket and fill them
+ * into a cache.
+ */
+int nl_cache_request_full_dump(struct nl_sock *sk, struct nl_cache *cache)
+{
+ NL_DBG(2, "Requesting dump from kernel for cache %p <%s>...\n",
+ cache, nl_cache_name(cache));
+
+ if (cache->c_ops->co_request_update == NULL)
+ return -NLE_OPNOTSUPP;
+
+ 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;
+
+ return nl_cache_parse(x->ops, &msg->nm_src, msg->nm_nlh, x->params);
+}
+/** @endcond */
+
+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(1, "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", 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)
+{
+ return nl_cache_add((struct nl_cache *) p->pp_arg, 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.
+ *
+ * @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);
+}
+
+
+/** @} */
+
+/**
+ * @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.
+ *
+ * @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)
+{
+ int err;
+
+ err = nl_cache_request_full_dump(sk, cache);
+ if (err < 0)
+ return err;
+
+ NL_DBG(2, "Upading cache %p <%s>, request sent, waiting for dump...\n",
+ cache, nl_cache_name(cache));
+ nl_cache_clear(cache);
+
+ return nl_cache_pickup(sk, cache);
+}
+
+/** @} */