snapraid/tommyds/tommyarray.c

84 lines
2.7 KiB
C

/*
* Copyright (c) 2011, Andrea Mazzoleni. 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
*/
#include "tommyarray.h"
/******************************************************************************/
/* array */
void tommy_array_init(tommy_array* array)
{
tommy_uint_t i;
/* fixed initial size */
array->bucket_bit = TOMMY_ARRAY_BIT;
array->bucket_max = (tommy_size_t)1 << array->bucket_bit;
array->bucket[0] = tommy_cast(void**, tommy_calloc(array->bucket_max, sizeof(void*)));
for (i = 1; i < TOMMY_ARRAY_BIT; ++i)
array->bucket[i] = array->bucket[0];
array->count = 0;
}
void tommy_array_done(tommy_array* array)
{
tommy_uint_t i;
tommy_free(array->bucket[0]);
for (i = TOMMY_ARRAY_BIT; i < array->bucket_bit; ++i) {
void** segment = array->bucket[i];
tommy_free(&segment[(tommy_ptrdiff_t)1 << i]);
}
}
void tommy_array_grow(tommy_array* array, tommy_size_t count)
{
if (array->count >= count)
return;
array->count = count;
while (count > array->bucket_max) {
void** segment;
/* allocate one more segment */
segment = tommy_cast(void**, tommy_calloc(array->bucket_max, sizeof(void*)));
/* store it adjusting the offset */
/* cast to ptrdiff_t to ensure to get a negative value */
array->bucket[array->bucket_bit] = &segment[-(tommy_ptrdiff_t)array->bucket_max];
++array->bucket_bit;
array->bucket_max = (tommy_size_t)1 << array->bucket_bit;
}
}
tommy_size_t tommy_array_memory_usage(tommy_array* array)
{
return array->bucket_max * (tommy_size_t)sizeof(void*);
}