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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2001 by Sun Microsystems, Inc.
* All rights reserved.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Routines for manipulating stacks
*/
#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#include "stack.h"
#include "memory.h"
#define STACK_SEEDSIZE 5
struct stk {
int st_nument;
int st_top;
void **st_data;
void (*st_free)(void *);
};
stk_t *
stack_new(void (*freep)(void *))
{
stk_t *sp;
sp = xmalloc(sizeof (stk_t));
sp->st_nument = STACK_SEEDSIZE;
sp->st_top = -1;
sp->st_data = xmalloc(sizeof (void *) * sp->st_nument);
sp->st_free = freep;
return (sp);
}
void
stack_free(stk_t *sp)
{
int i;
if (sp->st_free) {
for (i = 0; i <= sp->st_top; i++)
sp->st_free(sp->st_data[i]);
}
free(sp->st_data);
free(sp);
}
void *
stack_pop(stk_t *sp)
{
assert(sp->st_top >= 0);
return (sp->st_data[sp->st_top--]);
}
void *
stack_peek(stk_t *sp)
{
if (sp->st_top == -1)
return (NULL);
return (sp->st_data[sp->st_top]);
}
void
stack_push(stk_t *sp, void *data)
{
sp->st_top++;
if (sp->st_top == sp->st_nument) {
sp->st_nument += STACK_SEEDSIZE;
sp->st_data = xrealloc(sp->st_data,
sizeof (void *) * sp->st_nument);
}
sp->st_data[sp->st_top] = data;
}
int
stack_level(stk_t *sp)
{
return (sp->st_top + 1);
}
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