diff options
Diffstat (limited to 'main/astobj2_hash.c')
-rw-r--r-- | main/astobj2_hash.c | 1156 |
1 files changed, 1156 insertions, 0 deletions
diff --git a/main/astobj2_hash.c b/main/astobj2_hash.c new file mode 100644 index 000000000..f56aa72c7 --- /dev/null +++ b/main/astobj2_hash.c @@ -0,0 +1,1156 @@ +/* + * astobj2_hash - Hash table implementation for astobj2. + * + * Copyright (C) 2006 Marta Carbone, Luigi Rizzo - Univ. di Pisa, Italy + * + * See http://www.asterisk.org for more information about + * the Asterisk project. Please do not directly contact + * any of the maintainers of this project for assistance; + * the project provides a web site, mailing lists and IRC + * channels for your use. + * + * This program is free software, distributed under the terms of + * the GNU General Public License Version 2. See the LICENSE file + * at the top of the source tree. + */ + +/*! \file + * + * \brief Hash table functions implementing astobj2 containers. + * + * \author Richard Mudgett <rmudgett@digium.com> + */ + +#include "asterisk.h" + +ASTERISK_FILE_VERSION(__FILE__, "$Revision$") + +#include "asterisk/_private.h" +#include "asterisk/astobj2.h" +#include "astobj2_private.h" +#include "astobj2_container_private.h" +#include "asterisk/dlinkedlists.h" +#include "asterisk/utils.h" + +/*! + * A structure to create a linked list of entries, + * used within a bucket. + */ +struct hash_bucket_node { + /*! + * \brief Items common to all container nodes. + * \note Must be first in the specific node struct. + */ + struct ao2_container_node common; + /*! Next node links in the list. */ + AST_DLLIST_ENTRY(hash_bucket_node) links; + /*! Hash bucket holding the node. */ + int my_bucket; +}; + +struct hash_bucket { + /*! List of objects held in the bucket. */ + AST_DLLIST_HEAD_NOLOCK(, hash_bucket_node) list; +#if defined(AST_DEVMODE) + /*! Number of elements currently in the bucket. */ + int elements; + /*! Maximum number of elements in the bucket. */ + int max_elements; +#endif /* defined(AST_DEVMODE) */ +}; + +/*! + * A hash container in addition to values common to all + * container types, stores the hash callback function, the + * number of hash buckets, and the hash bucket heads. + */ +struct ao2_container_hash { + /*! + * \brief Items common to all containers. + * \note Must be first in the specific container struct. + */ + struct ao2_container common; + ao2_hash_fn *hash_fn; + /*! Number of hash buckets in this container. */ + int n_buckets; + /*! Hash bucket array of n_buckets. Variable size. */ + struct hash_bucket buckets[0]; +}; + +/*! Traversal state to restart a hash container traversal. */ +struct hash_traversal_state { + /*! Active sort function in the traversal if not NULL. */ + ao2_sort_fn *sort_fn; + /*! Saved comparison callback arg pointer. */ + void *arg; + /*! Starting hash bucket */ + int bucket_start; + /*! Stopping hash bucket */ + int bucket_last; + /*! Saved search flags to control traversing the container. */ + enum search_flags flags; + /*! TRUE if it is a descending search */ + unsigned int descending:1; +}; + +struct hash_traversal_state_check { + /* + * If we have a division by zero compile error here then there + * is not enough room for the state. Increase AO2_TRAVERSAL_STATE_SIZE. + */ + char check[1 / (AO2_TRAVERSAL_STATE_SIZE / sizeof(struct hash_traversal_state))]; +}; + +/*! + * \internal + * \brief Create an empty copy of this container. + * \since 12.0.0 + * + * \param self Container to operate upon. + * + * \retval empty-clone-container on success. + * \retval NULL on error. + */ +static struct ao2_container *hash_ao2_alloc_empty_clone(struct ao2_container_hash *self) +{ + if (!is_ao2_object(self)) { + return NULL; + } + + return ao2_t_container_alloc_hash(ao2_options_get(self), self->common.options, self->n_buckets, + self->hash_fn, self->common.sort_fn, self->common.cmp_fn, "Clone hash container"); +} + +/*! + * \internal + * \brief Create an empty copy of this container. (Debug version) + * \since 12.0.0 + * + * \param self Container to operate upon. + * \param tag used for debugging. + * \param file Debug file name invoked from + * \param line Debug line invoked from + * \param func Debug function name invoked from + * \param ref_debug TRUE if to output a debug reference message. + * + * \retval empty-clone-container on success. + * \retval NULL on error. + */ +static struct ao2_container *hash_ao2_alloc_empty_clone_debug(struct ao2_container_hash *self, const char *tag, const char *file, int line, const char *func, int ref_debug) +{ + if (!is_ao2_object(self)) { + return NULL; + } + + return __ao2_container_alloc_hash_debug(ao2_options_get(self), self->common.options, + self->n_buckets, self->hash_fn, self->common.sort_fn, self->common.cmp_fn, + tag, file, line, func, ref_debug); +} + +/*! + * \internal + * \brief Destroy a hash container list node. + * \since 12.0.0 + * + * \param v_doomed Container node to destroy. + * + * \details + * The container node unlinks itself from the container as part + * of its destruction. The node must be destroyed while the + * container is already locked. + * + * \note The container must be locked when the node is + * unreferenced. + * + * \return Nothing + */ +static void hash_ao2_node_destructor(void *v_doomed) +{ + struct hash_bucket_node *doomed = v_doomed; + + if (doomed->common.is_linked) { + struct ao2_container_hash *my_container; + struct hash_bucket *bucket; + + /* + * Promote to write lock if not already there. Since + * adjust_lock() can potentially release and block waiting for a + * write lock, care must be taken to ensure that node references + * are released before releasing the container references. + * + * Node references held by an iterator can only be held while + * the iterator also holds a reference to the container. These + * node references must be unreferenced before the container can + * be unreferenced to ensure that the node will not get a + * negative reference and the destructor called twice for the + * same node. + */ + my_container = (struct ao2_container_hash *) doomed->common.my_container; + __adjust_lock(my_container, AO2_LOCK_REQ_WRLOCK, 1); + +#if defined(AO2_DEBUG) && defined(AST_DEVMODE) + /* + * XXX chan_iax2 plays games with the hash function so we cannot + * routinely do an integrity check on this type of container. + * chan_iax2 should be changed to not abuse the hash function. + */ + if (!my_container->common.destroying + && my_container->common.sort_fn + && ao2_container_check(doomed->common.my_container, OBJ_NOLOCK)) { + ast_log(LOG_ERROR, "Container integrity failed before node deletion.\n"); + } +#endif /* defined(AO2_DEBUG) && defined(AST_DEVMODE) */ + bucket = &my_container->buckets[doomed->my_bucket]; + AST_DLLIST_REMOVE(&bucket->list, doomed, links); + AO2_DEVMODE_STAT(--my_container->common.nodes); + } + + /* + * We could have an object in the node if the container is being + * destroyed or the node had not been linked in yet. + */ + if (doomed->common.obj) { + ao2_t_ref(doomed->common.obj, -1, "Container node destruction"); + doomed->common.obj = NULL; + } +} + +/*! + * \internal + * \brief Create a new container node. + * \since 12.0.0 + * + * \param self Container to operate upon. + * \param obj_new Object to put into the node. + * \param tag used for debugging. + * \param file Debug file name invoked from + * \param line Debug line invoked from + * \param func Debug function name invoked from + * + * \retval initialized-node on success. + * \retval NULL on error. + */ +static struct hash_bucket_node *hash_ao2_new_node(struct ao2_container_hash *self, void *obj_new, const char *tag, const char *file, int line, const char *func) +{ + struct hash_bucket_node *node; + int i; + + node = __ao2_alloc(sizeof(*node), hash_ao2_node_destructor, AO2_ALLOC_OPT_LOCK_NOLOCK); + if (!node) { + return NULL; + } + + i = abs(self->hash_fn(obj_new, OBJ_SEARCH_OBJECT)); + i %= self->n_buckets; + + if (tag) { + __ao2_ref_debug(obj_new, +1, tag, file, line, func); + } else { + ao2_t_ref(obj_new, +1, "Container node creation"); + } + node->common.obj = obj_new; + node->common.my_container = (struct ao2_container *) self; + node->my_bucket = i; + + return node; +} + +/*! + * \internal + * \brief Insert a node into this container. + * \since 12.0.0 + * + * \param self Container to operate upon. + * \param node Container node to insert into the container. + * + * \return enum ao2_container_insert value. + */ +static enum ao2_container_insert hash_ao2_insert_node(struct ao2_container_hash *self, struct hash_bucket_node *node) +{ + int cmp; + struct hash_bucket *bucket; + struct hash_bucket_node *cur; + ao2_sort_fn *sort_fn; + uint32_t options; + + bucket = &self->buckets[node->my_bucket]; + sort_fn = self->common.sort_fn; + options = self->common.options; + + if (options & AO2_CONTAINER_ALLOC_OPT_INSERT_BEGIN) { + if (sort_fn) { + AST_DLLIST_TRAVERSE_BACKWARDS_SAFE_BEGIN(&bucket->list, cur, links) { + cmp = sort_fn(cur->common.obj, node->common.obj, OBJ_SEARCH_OBJECT); + if (cmp > 0) { + continue; + } + if (cmp < 0) { + AST_DLLIST_INSERT_AFTER_CURRENT(node, links); + return AO2_CONTAINER_INSERT_NODE_INSERTED; + } + switch (options & AO2_CONTAINER_ALLOC_OPT_DUPS_MASK) { + default: + case AO2_CONTAINER_ALLOC_OPT_DUPS_ALLOW: + break; + case AO2_CONTAINER_ALLOC_OPT_DUPS_REJECT: + /* Reject all objects with the same key. */ + return AO2_CONTAINER_INSERT_NODE_REJECTED; + case AO2_CONTAINER_ALLOC_OPT_DUPS_OBJ_REJECT: + if (cur->common.obj == node->common.obj) { + /* Reject inserting the same object */ + return AO2_CONTAINER_INSERT_NODE_REJECTED; + } + break; + case AO2_CONTAINER_ALLOC_OPT_DUPS_REPLACE: + SWAP(cur->common.obj, node->common.obj); + return AO2_CONTAINER_INSERT_NODE_OBJ_REPLACED; + } + } + AST_DLLIST_TRAVERSE_BACKWARDS_SAFE_END; + } + AST_DLLIST_INSERT_HEAD(&bucket->list, node, links); + } else { + if (sort_fn) { + AST_DLLIST_TRAVERSE_SAFE_BEGIN(&bucket->list, cur, links) { + cmp = sort_fn(cur->common.obj, node->common.obj, OBJ_SEARCH_OBJECT); + if (cmp < 0) { + continue; + } + if (cmp > 0) { + AST_DLLIST_INSERT_BEFORE_CURRENT(node, links); + return AO2_CONTAINER_INSERT_NODE_INSERTED; + } + switch (options & AO2_CONTAINER_ALLOC_OPT_DUPS_MASK) { + default: + case AO2_CONTAINER_ALLOC_OPT_DUPS_ALLOW: + break; + case AO2_CONTAINER_ALLOC_OPT_DUPS_REJECT: + /* Reject all objects with the same key. */ + return AO2_CONTAINER_INSERT_NODE_REJECTED; + case AO2_CONTAINER_ALLOC_OPT_DUPS_OBJ_REJECT: + if (cur->common.obj == node->common.obj) { + /* Reject inserting the same object */ + return AO2_CONTAINER_INSERT_NODE_REJECTED; + } + break; + case AO2_CONTAINER_ALLOC_OPT_DUPS_REPLACE: + SWAP(cur->common.obj, node->common.obj); + return AO2_CONTAINER_INSERT_NODE_OBJ_REPLACED; + } + } + AST_DLLIST_TRAVERSE_SAFE_END; + } + AST_DLLIST_INSERT_TAIL(&bucket->list, node, links); + } + return AO2_CONTAINER_INSERT_NODE_INSERTED; +} + +/*! + * \internal + * \brief Find the first hash container node in a traversal. + * \since 12.0.0 + * + * \param self Container to operate upon. + * \param flags search_flags to control traversing the container + * \param arg Comparison callback arg parameter. + * \param state Traversal state to restart hash container traversal. + * + * \retval node-ptr of found node (Reffed). + * \retval NULL when no node found. + */ +static struct hash_bucket_node *hash_ao2_find_first(struct ao2_container_hash *self, enum search_flags flags, void *arg, struct hash_traversal_state *state) +{ + struct hash_bucket_node *node; + int bucket_cur; + int cmp; + + memset(state, 0, sizeof(*state)); + state->arg = arg; + state->flags = flags; + + /* Determine traversal order. */ + switch (flags & OBJ_ORDER_MASK) { + case OBJ_ORDER_POST: + case OBJ_ORDER_DESCENDING: + state->descending = 1; + break; + case OBJ_ORDER_PRE: + case OBJ_ORDER_ASCENDING: + default: + break; + } + + /* + * If lookup by pointer or search key, run the hash and optional + * sort functions. Otherwise, traverse the whole container. + */ + switch (flags & OBJ_SEARCH_MASK) { + case OBJ_SEARCH_OBJECT: + case OBJ_SEARCH_KEY: + /* we know hash can handle this case */ + bucket_cur = abs(self->hash_fn(arg, flags & OBJ_SEARCH_MASK)); + bucket_cur %= self->n_buckets; + state->sort_fn = self->common.sort_fn; + break; + case OBJ_SEARCH_PARTIAL_KEY: + /* scan all buckets for partial key matches */ + bucket_cur = -1; + state->sort_fn = self->common.sort_fn; + break; + default: + /* don't know, let's scan all buckets */ + bucket_cur = -1; + state->sort_fn = NULL; + break; + } + + if (state->descending) { + /* + * Determine the search boundaries of a descending traversal. + * + * bucket_cur downto state->bucket_last + */ + if (bucket_cur < 0) { + bucket_cur = self->n_buckets - 1; + state->bucket_last = 0; + } else { + state->bucket_last = bucket_cur; + } + state->bucket_start = bucket_cur; + + /* For each bucket */ + for (; state->bucket_last <= bucket_cur; --bucket_cur) { + /* For each node in the bucket. */ + for (node = AST_DLLIST_LAST(&self->buckets[bucket_cur].list); + node; + node = AST_DLLIST_PREV(node, links)) { + if (!node->common.obj) { + /* Node is empty */ + continue; + } + + if (state->sort_fn) { + /* Filter node through the sort_fn */ + cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK); + if (cmp > 0) { + continue; + } + if (cmp < 0) { + /* No more nodes in this bucket are possible to match. */ + break; + } + } + + /* We have the first traversal node */ + __ao2_ref(node, +1); + return node; + } + } + } else { + /* + * Determine the search boundaries of an ascending traversal. + * + * bucket_cur to state->bucket_last-1 + */ + if (bucket_cur < 0) { + bucket_cur = 0; + state->bucket_last = self->n_buckets; + } else { + state->bucket_last = bucket_cur + 1; + } + state->bucket_start = bucket_cur; + + /* For each bucket */ + for (; bucket_cur < state->bucket_last; ++bucket_cur) { + /* For each node in the bucket. */ + for (node = AST_DLLIST_FIRST(&self->buckets[bucket_cur].list); + node; + node = AST_DLLIST_NEXT(node, links)) { + if (!node->common.obj) { + /* Node is empty */ + continue; + } + + if (state->sort_fn) { + /* Filter node through the sort_fn */ + cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK); + if (cmp < 0) { + continue; + } + if (cmp > 0) { + /* No more nodes in this bucket are possible to match. */ + break; + } + } + + /* We have the first traversal node */ + __ao2_ref(node, +1); + return node; + } + } + } + + return NULL; +} + +/*! + * \internal + * \brief Find the next hash container node in a traversal. + * \since 12.0.0 + * + * \param self Container to operate upon. + * \param state Traversal state to restart hash container traversal. + * \param prev Previous node returned by the traversal search functions. + * The ref ownership is passed back to this function. + * + * \retval node-ptr of found node (Reffed). + * \retval NULL when no node found. + */ +static struct hash_bucket_node *hash_ao2_find_next(struct ao2_container_hash *self, struct hash_traversal_state *state, struct hash_bucket_node *prev) +{ + struct hash_bucket_node *node; + void *arg; + enum search_flags flags; + int bucket_cur; + int cmp; + + arg = state->arg; + flags = state->flags; + bucket_cur = prev->my_bucket; + node = prev; + + /* + * This function is structured the same as hash_ao2_find_first() + * intentionally. We are resuming the search loops from + * hash_ao2_find_first() in order to find the next node. The + * search loops must be resumed where hash_ao2_find_first() + * returned with the first node. + */ + if (state->descending) { + goto hash_descending_resume; + + /* For each bucket */ + for (; state->bucket_last <= bucket_cur; --bucket_cur) { + /* For each node in the bucket. */ + for (node = AST_DLLIST_LAST(&self->buckets[bucket_cur].list); + node; + node = AST_DLLIST_PREV(node, links)) { + if (!node->common.obj) { + /* Node is empty */ + continue; + } + + if (state->sort_fn) { + /* Filter node through the sort_fn */ + cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK); + if (cmp > 0) { + continue; + } + if (cmp < 0) { + /* No more nodes in this bucket are possible to match. */ + break; + } + } + + /* We have the next traversal node */ + __ao2_ref(node, +1); + + /* + * Dereferencing the prev node may result in our next node + * object being removed by another thread. This could happen if + * the container uses RW locks and the container was read + * locked. + */ + __ao2_ref(prev, -1); + if (node->common.obj) { + return node; + } + prev = node; + +hash_descending_resume:; + } + } + } else { + goto hash_ascending_resume; + + /* For each bucket */ + for (; bucket_cur < state->bucket_last; ++bucket_cur) { + /* For each node in the bucket. */ + for (node = AST_DLLIST_FIRST(&self->buckets[bucket_cur].list); + node; + node = AST_DLLIST_NEXT(node, links)) { + if (!node->common.obj) { + /* Node is empty */ + continue; + } + + if (state->sort_fn) { + /* Filter node through the sort_fn */ + cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK); + if (cmp < 0) { + continue; + } + if (cmp > 0) { + /* No more nodes in this bucket are possible to match. */ + break; + } + } + + /* We have the next traversal node */ + __ao2_ref(node, +1); + + /* + * Dereferencing the prev node may result in our next node + * object being removed by another thread. This could happen if + * the container uses RW locks and the container was read + * locked. + */ + __ao2_ref(prev, -1); + if (node->common.obj) { + return node; + } + prev = node; + +hash_ascending_resume:; + } + } + } + + /* No more nodes in the container left to traverse. */ + __ao2_ref(prev, -1); + return NULL; +} + +/*! + * \internal + * \brief Find the next non-empty iteration node in the container. + * \since 12.0.0 + * + * \param self Container to operate upon. + * \param node Previous node returned by the iterator. + * \param flags search_flags to control iterating the container. + * Only AO2_ITERATOR_DESCENDING is useful by the method. + * + * \note The container is already locked. + * + * \retval node on success. + * \retval NULL on error or no more nodes in the container. + */ +static struct hash_bucket_node *hash_ao2_iterator_next(struct ao2_container_hash *self, struct hash_bucket_node *node, enum ao2_iterator_flags flags) +{ + int cur_bucket; + + if (flags & AO2_ITERATOR_DESCENDING) { + if (node) { + cur_bucket = node->my_bucket; + + /* Find next non-empty node. */ + for (;;) { + node = AST_DLLIST_PREV(node, links); + if (!node) { + break; + } + if (node->common.obj) { + /* Found a non-empty node. */ + return node; + } + } + } else { + /* Find first non-empty node. */ + cur_bucket = self->n_buckets; + } + + /* Find a non-empty node in the remaining buckets */ + while (0 <= --cur_bucket) { + node = AST_DLLIST_LAST(&self->buckets[cur_bucket].list); + while (node) { + if (node->common.obj) { + /* Found a non-empty node. */ + return node; + } + node = AST_DLLIST_PREV(node, links); + } + } + } else { + if (node) { + cur_bucket = node->my_bucket; + + /* Find next non-empty node. */ + for (;;) { + node = AST_DLLIST_NEXT(node, links); + if (!node) { + break; + } + if (node->common.obj) { + /* Found a non-empty node. */ + return node; + } + } + } else { + /* Find first non-empty node. */ + cur_bucket = -1; + } + + /* Find a non-empty node in the remaining buckets */ + while (++cur_bucket < self->n_buckets) { + node = AST_DLLIST_FIRST(&self->buckets[cur_bucket].list); + while (node) { + if (node->common.obj) { + /* Found a non-empty node. */ + return node; + } + node = AST_DLLIST_NEXT(node, links); + } + } + } + + /* No more nodes to visit in the container. */ + return NULL; +} + +#if defined(AST_DEVMODE) +/*! + * \internal + * \brief Increment the hash container linked object statistic. + * \since 12.0.0 + * + * \param hash Container to operate upon. + * \param hash_node Container node linking object to. + * + * \return Nothing + */ +void hash_ao2_link_node_stat(struct ao2_container *hash, struct ao2_container_node *hash_node) +{ + struct ao2_container_hash *self = (struct ao2_container_hash *) hash; + struct hash_bucket_node *node = (struct hash_bucket_node *) hash_node; + int i = node->my_bucket; + + ++self->buckets[i].elements; + if (self->buckets[i].max_elements < self->buckets[i].elements) { + self->buckets[i].max_elements = self->buckets[i].elements; + } +} +#endif /* defined(AST_DEVMODE) */ + +#if defined(AST_DEVMODE) +/*! + * \internal + * \brief Decrement the hash container linked object statistic. + * \since 12.0.0 + * + * \param hash Container to operate upon. + * \param hash_node Container node unlinking object from. + * + * \return Nothing + */ +void hash_ao2_unlink_node_stat(struct ao2_container *hash, struct ao2_container_node *hash_node) +{ + struct ao2_container_hash *self = (struct ao2_container_hash *) hash; + struct hash_bucket_node *node = (struct hash_bucket_node *) hash_node; + + --self->buckets[node->my_bucket].elements; +} +#endif /* defined(AST_DEVMODE) */ + +/*! + * \internal + * + * \brief Destroy this container. + * \since 12.0.0 + * + * \param self Container to operate upon. + * + * \return Nothing + */ +static void hash_ao2_destroy(struct ao2_container_hash *self) +{ + int idx; + + /* Check that the container no longer has any nodes */ + for (idx = self->n_buckets; idx--;) { + if (!AST_DLLIST_EMPTY(&self->buckets[idx].list)) { + ast_log(LOG_ERROR, "Node ref leak. Hash container still has nodes!\n"); + ast_assert(0); + break; + } + } +} + +#if defined(AST_DEVMODE) +/*! + * \internal + * \brief Display contents of the specified container. + * \since 12.0.0 + * + * \param self Container to dump. + * \param where User data needed by prnt to determine where to put output. + * \param prnt Print output callback function to use. + * \param prnt_obj Callback function to print the given object's key. (NULL if not available) + * + * \return Nothing + */ +static void hash_ao2_dump(struct ao2_container_hash *self, void *where, ao2_prnt_fn *prnt, ao2_prnt_obj_fn *prnt_obj) +{ +#define FORMAT "%6s, %16s, %16s, %16s, %16s, %s\n" +#define FORMAT2 "%6d, %16p, %16p, %16p, %16p, " + + int bucket; + int suppressed_buckets = 0; + struct hash_bucket_node *node; + + prnt(where, "Number of buckets: %d\n\n", self->n_buckets); + + prnt(where, FORMAT, "Bucket", "Node", "Prev", "Next", "Obj", "Key"); + for (bucket = 0; bucket < self->n_buckets; ++bucket) { + node = AST_DLLIST_FIRST(&self->buckets[bucket].list); + if (node) { + suppressed_buckets = 0; + do { + prnt(where, FORMAT2, + bucket, + node, + AST_DLLIST_PREV(node, links), + AST_DLLIST_NEXT(node, links), + node->common.obj); + if (node->common.obj && prnt_obj) { + prnt_obj(node->common.obj, where, prnt); + } + prnt(where, "\n"); + + node = AST_DLLIST_NEXT(node, links); + } while (node); + } else if (!suppressed_buckets) { + suppressed_buckets = 1; + prnt(where, "...\n"); + } + } + +#undef FORMAT +#undef FORMAT2 +} +#endif /* defined(AST_DEVMODE) */ + +#if defined(AST_DEVMODE) +/*! + * \internal + * \brief Display statistics of the specified container. + * \since 12.0.0 + * + * \param self Container to display statistics. + * \param where User data needed by prnt to determine where to put output. + * \param prnt Print output callback function to use. + * + * \note The container is already locked for reading. + * + * \return Nothing + */ +static void hash_ao2_stats(struct ao2_container_hash *self, void *where, ao2_prnt_fn *prnt) +{ +#define FORMAT "%10.10s %10.10s %10.10s\n" +#define FORMAT2 "%10d %10d %10d\n" + + int bucket; + int suppressed_buckets = 0; + + prnt(where, "Number of buckets: %d\n\n", self->n_buckets); + + prnt(where, FORMAT, "Bucket", "Objects", "Max"); + for (bucket = 0; bucket < self->n_buckets; ++bucket) { + if (self->buckets[bucket].max_elements) { + suppressed_buckets = 0; + prnt(where, FORMAT2, bucket, self->buckets[bucket].elements, + self->buckets[bucket].max_elements); + } else if (!suppressed_buckets) { + suppressed_buckets = 1; + prnt(where, "...\n"); + } + } + +#undef FORMAT +#undef FORMAT2 +} +#endif /* defined(AST_DEVMODE) */ + +#if defined(AST_DEVMODE) +/*! + * \internal + * \brief Perform an integrity check on the specified container. + * \since 12.0.0 + * + * \param self Container to check integrity. + * + * \note The container is already locked for reading. + * + * \retval 0 on success. + * \retval -1 on error. + */ +static int hash_ao2_integrity(struct ao2_container_hash *self) +{ + int bucket_exp; + int bucket; + int count_obj; + int count_total_obj; + int count_total_node; + void *obj_last; + struct hash_bucket_node *node; + struct hash_bucket_node *prev; + struct hash_bucket_node *next; + + count_total_obj = 0; + count_total_node = 0; + + /* For each bucket in the container. */ + for (bucket = 0; bucket < self->n_buckets; ++bucket) { + if (!AST_DLLIST_FIRST(&self->buckets[bucket].list) + && !AST_DLLIST_LAST(&self->buckets[bucket].list)) { + /* The bucket list is empty. */ + continue; + } + + count_obj = 0; + obj_last = NULL; + + /* Check bucket list links and nodes. */ + node = AST_DLLIST_LAST(&self->buckets[bucket].list); + if (!node) { + ast_log(LOG_ERROR, "Bucket %d list tail is NULL when it should not be!\n", + bucket); + return -1; + } + if (AST_DLLIST_NEXT(node, links)) { + ast_log(LOG_ERROR, "Bucket %d list tail node is not the last node!\n", + bucket); + return -1; + } + node = AST_DLLIST_FIRST(&self->buckets[bucket].list); + if (!node) { + ast_log(LOG_ERROR, "Bucket %d list head is NULL when it should not be!\n", + bucket); + return -1; + } + if (AST_DLLIST_PREV(node, links)) { + ast_log(LOG_ERROR, "Bucket %d list head node is not the first node!\n", + bucket); + return -1; + } + for (; node; node = next) { + /* Check backward link. */ + prev = AST_DLLIST_PREV(node, links); + if (prev) { + if (prev == node) { + ast_log(LOG_ERROR, "Bucket %d list node's prev pointer points to itself!\n", + bucket); + return -1; + } + if (node != AST_DLLIST_NEXT(prev, links)) { + ast_log(LOG_ERROR, "Bucket %d list node's prev node does not link back!\n", + bucket); + return -1; + } + } else if (node != AST_DLLIST_FIRST(&self->buckets[bucket].list)) { + ast_log(LOG_ERROR, "Bucket %d backward list chain is broken!\n", + bucket); + return -1; + } + + /* Check forward link. */ + next = AST_DLLIST_NEXT(node, links); + if (next) { + if (next == node) { + ast_log(LOG_ERROR, "Bucket %d list node's next pointer points to itself!\n", + bucket); + return -1; + } + if (node != AST_DLLIST_PREV(next, links)) { + ast_log(LOG_ERROR, "Bucket %d list node's next node does not link back!\n", + bucket); + return -1; + } + } else if (node != AST_DLLIST_LAST(&self->buckets[bucket].list)) { + ast_log(LOG_ERROR, "Bucket %d forward list chain is broken!\n", + bucket); + return -1; + } + + if (bucket != node->my_bucket) { + ast_log(LOG_ERROR, "Bucket %d node claims to be in bucket %d!\n", + bucket, node->my_bucket); + return -1; + } + + ++count_total_node; + if (!node->common.obj) { + /* Node is empty. */ + continue; + } + ++count_obj; + + /* Check container hash key for expected bucket. */ + bucket_exp = abs(self->hash_fn(node->common.obj, OBJ_SEARCH_OBJECT)); + bucket_exp %= self->n_buckets; + if (bucket != bucket_exp) { + ast_log(LOG_ERROR, "Bucket %d node hashes to bucket %d!\n", + bucket, bucket_exp); + return -1; + } + + /* Check sort if configured. */ + if (self->common.sort_fn) { + if (obj_last + && self->common.sort_fn(obj_last, node->common.obj, OBJ_SEARCH_OBJECT) > 0) { + ast_log(LOG_ERROR, "Bucket %d nodes out of sorted order!\n", + bucket); + return -1; + } + obj_last = node->common.obj; + } + } + + /* Check bucket obj count statistic. */ + if (count_obj != self->buckets[bucket].elements) { + ast_log(LOG_ERROR, "Bucket %d object count of %d does not match stat of %d!\n", + bucket, count_obj, self->buckets[bucket].elements); + return -1; + } + + /* Accumulate found object counts. */ + count_total_obj += count_obj; + } + + /* Check total obj count. */ + if (count_total_obj != ao2_container_count(&self->common)) { + ast_log(LOG_ERROR, + "Total object count of %d does not match ao2_container_count() of %d!\n", + count_total_obj, ao2_container_count(&self->common)); + return -1; + } + + /* Check total node count. */ + if (count_total_node != self->common.nodes) { + ast_log(LOG_ERROR, "Total node count of %d does not match stat of %d!\n", + count_total_node, self->common.nodes); + return -1; + } + + return 0; +} +#endif /* defined(AST_DEVMODE) */ + +/*! Hash container virtual method table. */ +static const struct ao2_container_methods v_table_hash = { + .type = AO2_CONTAINER_RTTI_HASH, + .alloc_empty_clone = (ao2_container_alloc_empty_clone_fn) hash_ao2_alloc_empty_clone, + .alloc_empty_clone_debug = + (ao2_container_alloc_empty_clone_debug_fn) hash_ao2_alloc_empty_clone_debug, + .new_node = (ao2_container_new_node_fn) hash_ao2_new_node, + .insert = (ao2_container_insert_fn) hash_ao2_insert_node, + .traverse_first = (ao2_container_find_first_fn) hash_ao2_find_first, + .traverse_next = (ao2_container_find_next_fn) hash_ao2_find_next, + .iterator_next = (ao2_iterator_next_fn) hash_ao2_iterator_next, + .destroy = (ao2_container_destroy_fn) hash_ao2_destroy, +#if defined(AST_DEVMODE) + .dump = (ao2_container_display) hash_ao2_dump, + .stats = (ao2_container_statistics) hash_ao2_stats, + .integrity = (ao2_container_integrity) hash_ao2_integrity, +#endif /* defined(AST_DEVMODE) */ +}; + +/*! + * \brief always zero hash function + * + * it is convenient to have a hash function that always returns 0. + * This is basically used when we want to have a container that is + * a simple linked list. + * + * \returns 0 + */ +static int hash_zero(const void *user_obj, const int flags) +{ + return 0; +} + +/*! + * \brief Initialize a hash container with the desired number of buckets. + * + * \param self Container to initialize. + * \param options Container behaviour options (See enum ao2_container_opts) + * \param n_buckets Number of buckets for hash + * \param hash_fn Pointer to a function computing a hash value. + * \param sort_fn Pointer to a sort function. + * \param cmp_fn Pointer to a compare function used by ao2_find. + * + * \return A pointer to a struct container. + */ +static struct ao2_container *hash_ao2_container_init( + struct ao2_container_hash *self, unsigned int options, unsigned int n_buckets, + ao2_hash_fn *hash_fn, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn) +{ + if (!self) { + return NULL; + } + + self->common.v_table = &v_table_hash; + self->common.sort_fn = sort_fn; + self->common.cmp_fn = cmp_fn; + self->common.options = options; + self->hash_fn = hash_fn ? hash_fn : hash_zero; + self->n_buckets = n_buckets; + +#ifdef AO2_DEBUG + ast_atomic_fetchadd_int(&ao2.total_containers, 1); +#endif + + return (struct ao2_container *) self; +} + +struct ao2_container *__ao2_container_alloc_hash(unsigned int ao2_options, + unsigned int container_options, unsigned int n_buckets, ao2_hash_fn *hash_fn, + ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn) +{ + unsigned int num_buckets; + size_t container_size; + struct ao2_container_hash *self; + + num_buckets = hash_fn ? n_buckets : 1; + container_size = sizeof(struct ao2_container_hash) + num_buckets * sizeof(struct hash_bucket); + + self = ao2_t_alloc_options(container_size, container_destruct, ao2_options, + "New hash container"); + return hash_ao2_container_init(self, container_options, num_buckets, + hash_fn, sort_fn, cmp_fn); +} + +struct ao2_container *__ao2_container_alloc_hash_debug(unsigned int ao2_options, + unsigned int container_options, unsigned int n_buckets, ao2_hash_fn *hash_fn, + ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn, + const char *tag, const char *file, int line, const char *func, int ref_debug) +{ + unsigned int num_buckets; + size_t container_size; + struct ao2_container_hash *self; + + num_buckets = hash_fn ? n_buckets : 1; + container_size = sizeof(struct ao2_container_hash) + num_buckets * sizeof(struct hash_bucket); + + self = __ao2_alloc_debug(container_size, + ref_debug ? container_destruct_debug : container_destruct, ao2_options, + tag, file, line, func, ref_debug); + return hash_ao2_container_init(self, container_options, num_buckets, hash_fn, + sort_fn, cmp_fn); +} + +struct ao2_container *__ao2_container_alloc_list(unsigned int ao2_options, + unsigned int container_options, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn) +{ + return __ao2_container_alloc_hash(ao2_options, container_options, 1, NULL, sort_fn, + cmp_fn); +} + +struct ao2_container *__ao2_container_alloc_list_debug(unsigned int ao2_options, + unsigned int container_options, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn, + const char *tag, const char *file, int line, const char *func, int ref_debug) +{ + return __ao2_container_alloc_hash_debug(ao2_options, container_options, 1, NULL, + sort_fn, cmp_fn, tag, file, line, func, ref_debug); +} + |