rculfhash: constify all key arguments passed to API

[urcu.git] / urcu / rculfhash.h

diff --git a/urcu/rculfhash.h b/urcu/rculfhash.h
index a1ae0f5a8fef9e80e39d8f21750005b565810cd7..9208011d900b3770184df8ed2d7d5f2106201a13 100644 (file)
--- a/urcu/rculfhash.h
+++ b/urcu/rculfhash.h
@@ -26,13 +26,13 @@
  */
 
 #include <stdint.h>
+#include <urcu/compiler.h>
 #include <urcu-call-rcu.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-
 /*
  * cds_lfht_node: Contains the next pointers and reverse-hash
  * value required for lookup and traversal of the hash table.
@@ -49,7 +49,7 @@ extern "C" {
  * of the hash value for cds_lfht APIs.
  */
 struct cds_lfht_node {
-       struct cds_lfht_node *next;     /* ptr | DUMMY_FLAG | REMOVED_FLAG */
+       struct cds_lfht_node *next;     /* ptr | BUCKET_FLAG | REMOVED_FLAG */
        unsigned long reverse_hash;
 } __attribute__((aligned(4)));
 
@@ -71,9 +71,7 @@ struct cds_lfht;
  * Ensure reader and writer threads are registered as urcu readers.
  */
 
-typedef unsigned long (*cds_lfht_hash_fct)(void *key, size_t length,
-                                       unsigned long seed);
-typedef int (*cds_lfht_match_fct)(struct cds_lfht_node *node, void *key);
+typedef int (*cds_lfht_match_fct)(struct cds_lfht_node *node, const void *key);
 
 /*
  * cds_lfht_node_init - initialize a hash table node
@@ -179,15 +177,17 @@ void cds_lfht_count_nodes(struct cds_lfht *ht,
 /*
  * cds_lfht_lookup - lookup a node by key.
  * @ht: the hash table.
- * @match: the key match function.
  * @hash: the key hash.
+ * @match: the key match function.
+ * @key: the current node key.
  * @iter: Node, if found (output). *iter->node set to NULL if not found.
  *
  * Call with rcu_read_lock held.
  * Threads calling this API need to be registered RCU read-side threads.
  */
-void cds_lfht_lookup(struct cds_lfht *ht, cds_lfht_match_fct match,
-               unsigned long hash, void *key, struct cds_lfht_iter *iter);
+void cds_lfht_lookup(struct cds_lfht *ht, unsigned long hash,
+               cds_lfht_match_fct match, const void *key,
+               struct cds_lfht_iter *iter);
 
 /*
  * cds_lfht_next_duplicate - get the next item with same key (after a lookup).
@@ -206,7 +206,7 @@ void cds_lfht_lookup(struct cds_lfht *ht, cds_lfht_match_fct match,
  * Threads calling this API need to be registered RCU read-side threads.
  */
 void cds_lfht_next_duplicate(struct cds_lfht *ht,
-               cds_lfht_match_fct match, void *key,
+               cds_lfht_match_fct match, const void *key,
                struct cds_lfht_iter *iter);
 
 /*
@@ -248,9 +248,9 @@ void cds_lfht_add(struct cds_lfht *ht, unsigned long hash,
 /*
  * cds_lfht_add_unique - add a node to hash table, if key is not present.
  * @ht: the hash table.
+ * @hash: the node's hash.
  * @match: the key match function.
  * @key: the node's key.
- * @hash: the node's hash.
  * @node: the node to try adding.
  *
  * Return the node added upon success.
@@ -266,17 +266,17 @@ void cds_lfht_add(struct cds_lfht *ht, unsigned long hash,
  * add_unique and add_replace (see below).
  */
 struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
-               cds_lfht_match_fct match,
-               void *key,
                unsigned long hash,
+               cds_lfht_match_fct match,
+               const void *key,
                struct cds_lfht_node *node);
 
 /*
  * cds_lfht_add_replace - replace or add a node within hash table.
  * @ht: the hash table.
+ * @hash: the node's hash.
  * @match: the key match function.
  * @key: the node's key.
- * @hash: the node's hash.
  * @node: the node to add.
  *
  * Return the node replaced upon success. If no node matching the key
@@ -298,9 +298,9 @@ struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
  * will never generate duplicated keys.
  */
 struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
-               cds_lfht_match_fct match,
-               void *key,
                unsigned long hash,
+               cds_lfht_match_fct match,
+               const void *key,
                struct cds_lfht_node *node);
 
 /*
@@ -362,6 +362,43 @@ int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_iter *iter);
  */
 void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size);
 
+/*
+ * Note: cds_lfht_for_each are safe for element removal during
+ * iteration.
+ */
+#define cds_lfht_for_each(ht, iter, node)                              \
+       for (cds_lfht_first(ht, iter),                                  \
+                       node = cds_lfht_iter_get_node(iter);            \
+               node != NULL;                                           \
+               cds_lfht_next(ht, iter),                                \
+                       node = cds_lfht_iter_get_node(iter))
+
+#define cds_lfht_for_each_duplicate(ht, hash, match, key, iter, node)  \
+       for (cds_lfht_lookup(ht, hash, match, key, iter),               \
+                       node = cds_lfht_iter_get_node(iter);            \
+               node != NULL;                                           \
+               cds_lfht_next_duplicate(ht, match, key, iter),          \
+                       node = cds_lfht_iter_get_node(iter))
+
+#define cds_lfht_for_each_entry(ht, iter, pos, member)                 \
+       for (cds_lfht_first(ht, iter),                                  \
+                       pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+                                       typeof(*(pos)), member);        \
+               &(pos)->member != NULL;                                 \
+               cds_lfht_next(ht, iter),                                \
+                       pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+                                       typeof(*(pos)), member))
+
+#define cds_lfht_for_each_entry_duplicate(ht, hash, match, key,                \
+                               iter, pos, member)                      \
+       for (cds_lfht_lookup(ht, hash, match, key, iter),               \
+                       pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+                                       typeof(*(pos)), member);        \
+               &(pos)->member != NULL;                                 \
+               cds_lfht_next_duplicate(ht, match, key, iter),          \
+                       pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+                                       typeof(*(pos)), member))
+
 #ifdef __cplusplus
 }
 #endif