+++ /dev/null
-/*
- * 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);
-}
-
-/** @} */
projects / openwrt / openwrt.git / blobdiff