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diff --git a/doc/ck_ht_get_spmc b/doc/ck_ht_get_spmc new file mode 100644 index 0000000..91b9534 --- /dev/null +++ b/doc/ck_ht_get_spmc @@ -0,0 +1,177 @@ +.\" +.\" Copyright 2012-2013 Samy Al Bahra. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" +.Dd March 29, 2012 +.Dt CK_HT_GET_SPMC 3 +.Sh NAME +.Nm ck_ht_get_spmc +.Nd load a key-value pair from a hash table +.Sh LIBRARY +Concurrency Kit (libck, \-lck) +.Sh SYNOPSIS +.In ck_ht.h +.Ft bool +.Fn ck_ht_get_spmc "ck_ht_t *ht" "ck_ht_hash_t h" "ck_ht_entry_t *entry" +.Sh DESCRIPTION +The +.Fn ck_ht_get_spmc +function will return the value associated with the key specified in the +.Fa entry +argument in the hash table pointed to by the +.Fa ht +argument. The key specified in +.Fa entry +is expected to have the hash value specified by the +.Fa h +argument. +.Pp +If +.Fa ht +was created with CK_HT_MODE_BYTESTRING then +.Fa entry +must have been initialized with the +.Xr ck_ht_entry_set_key 3 +or +.Xr ck_ht_entry_set 3 +functions. If +.Fa ht +was created with CK_HT_MODE_DIRECT then +.Fa entry +must have been initialized with the +.Xr ck_ht_entry_key_set_direct 3 +or +.Xr ck_ht_entry_set_direct 3 +functions. +.Pp +It is expected that +.Fa h +was initialized with +.Xr ck_ht_hash 3 +if +.Fa ht +was created with CK_HT_MODE_BYTESTRING. If +.Fa ht +was initialized with CK_HT_MODE_DIRECT then it is +expected that +.Fa h +was initialized with the +.Xr ck_ht_hash_direct 3 +function. +.Pp +If the call to +.Fn ck_ht_get_spmc +was successful then the key-value pair in +.Fa entry +was successfully found in the hash table pointed +to by +.Fa h +and will fail if the key specified in +.Fa entry +does not exist in the hash table. If successful +.Fa entry +will contain the key-value pair found in the hash table +pointed to by the +.Fa ht +argument. +.Pp +If +.Fa ht +was initialized with CK_HT_MODE_BYTESTRING then +the key/value pair in +.Fa entry +may be extracted using the +.Xr ck_ht_entry_key 3 +and +.Xr ck_ht_entry_value 3 +functions. The length of the key may be extracted +using the +.Xr ck_ht_entry_key_length 3 +function. +.Pp +If +.Fa ht +was initialized with CK_HT_MODE_DIRECT then the +key/value pair in +.Fa entry +may be extracted using the +.Xr ck_ht_entry_key_direct 3 +and +.Xr ck_ht_entry_value_direct 3 +functions. +.Pp +This function is safe to call in the presence of a concurrent writer. +.Sh RETURN VALUES +Upon successful completion +.Fn ck_ht_get_spmc +returns +.Dv true. +If successful, +.Fa entry +will contain the key/value pair as found +in the hash table. +Otherwise the function returns +.Dv false +on failure. +.Sh ERRORS +.Bl -tag -width Er +Behavior is undefined if +.Fa entry +or +.Fa ht +are uninitialized. The function will return +.Dv false +if the key as specified in +.Fa entry +was not found in the hash table. +.El +.Sh SEE ALSO +.Xr ck_ht_stat 3 , +.Xr ck_ht_init 3 , +.Xr ck_ht_destroy 3 , +.Xr ck_ht_hash 3 , +.Xr ck_ht_hash_direct 3 , +.Xr ck_ht_set_spmc 3 , +.Xr ck_ht_put_spmc 3 , +.Xr ck_ht_gc 3 , +.Xr ck_ht_grow_spmc 3 , +.Xr ck_ht_remove_spmc 3 , +.Xr ck_ht_reset_spmc 3 , +.Xr ck_ht_reset_size_spmc 3 , +.Xr ck_ht_count 3 , +.Xr ck_ht_entry_empty 3 , +.Xr ck_ht_entry_key_set 3 , +.Xr ck_ht_entry_key_set_direct 3 , +.Xr ck_ht_entry_key 3 , +.Xr ck_ht_entry_key_length 3 , +.Xr ck_ht_entry_value 3 , +.Xr ck_ht_entry_set 3 , +.Xr ck_ht_entry_set_direct 3 , +.Xr ck_ht_entry_key_direct 3 , +.Xr ck_ht_entry_value_direct 3 , +.Xr ck_ht_iterator_init 3 , +.Xr ck_ht_next 3 +.Pp +Additional information available at http://concurrencykit.org/ |