badvpn/misc/exparray.h
2012-01-27 13:24:37 +00:00

102 lines
2.7 KiB
C

/**
* @file exparray.h
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* 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.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* 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 AUTHOR 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.
*
* @section DESCRIPTION
*
* Dynamic array which grows exponentionally on demand.
*/
#ifndef BADVPN_MISC_EXPARRAY_H
#define BADVPN_MISC_EXPARRAY_H
#include <stddef.h>
#include <stdlib.h>
#include <limits.h>
#include <misc/debug.h>
struct ExpArray {
size_t esize;
size_t size;
void *v;
};
static int ExpArray_init (struct ExpArray *o, size_t esize, size_t size)
{
ASSERT(esize > 0)
ASSERT(size > 0)
o->esize = esize;
o->size = size;
if (o->size > SIZE_MAX / o->esize) {
return 0;
}
if (!(o->v = malloc(o->size * o->esize))) {
return 0;
}
return 1;
}
static int ExpArray_resize (struct ExpArray *o, size_t size)
{
ASSERT(size > 0)
if (size <= o->size) {
return 1;
}
size_t newsize = o->size;
while (newsize < size) {
if (2 > SIZE_MAX / newsize) {
return 0;
}
newsize = 2 * newsize;
}
if (newsize > SIZE_MAX / o->esize) {
return 0;
}
void *newarr = realloc(o->v, newsize * o->esize);
if (!newarr) {
return 0;
}
o->size = newsize;
o->v = newarr;
return 1;
}
#endif