usr/src/tools/ctf/cvt/stack.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2001 by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 /*
  30  * Routines for manipulating stacks
  31  */
  32
  33 #include <stdio.h>
  34 #include <assert.h>
  35 #include <stdlib.h>
  36
  37 #include "stack.h"
  38 #include "memory.h"
  39
  40 #define STACK_SEEDSIZE  5
  41
  42 struct stk {
  43         int st_nument;
  44         int st_top;
  45         void **st_data;
  46
  47         void (*st_free)(void *);
  48 };
  49
  50 stk_t *
  51 stack_new(void (*freep)(void *))
  52 {
  53         stk_t *sp;
  54
  55         sp = xmalloc(sizeof (stk_t));
  56         sp->st_nument = STACK_SEEDSIZE;
  57         sp->st_top = -1;
  58         sp->st_data = xmalloc(sizeof (void *) * sp->st_nument);
  59         sp->st_free = freep;
  60
  61         return (sp);
  62 }
  63
  64 void
  65 stack_free(stk_t *sp)
  66 {
  67         int i;
  68
  69         if (sp->st_free) {
  70                 for (i = 0; i <= sp->st_top; i++)
  71                         sp->st_free(sp->st_data[i]);
  72         }
  73         free(sp->st_data);
  74         free(sp);
  75 }
  76
  77 void *
  78 stack_pop(stk_t *sp)
  79 {
  80         assert(sp->st_top >= 0);
  81
  82         return (sp->st_data[sp->st_top--]);
  83 }
  84
  85 void *
  86 stack_peek(stk_t *sp)
  87 {
  88         if (sp->st_top == -1)
  89                 return (NULL);
  90
  91         return (sp->st_data[sp->st_top]);
  92 }
  93
  94 void
  95 stack_push(stk_t *sp, void *data)
  96 {
  97         sp->st_top++;
  98
  99         if (sp->st_top == sp->st_nument) {
 100                 sp->st_nument += STACK_SEEDSIZE;
 101                 sp->st_data = xrealloc(sp->st_data,
 102                     sizeof (void *) * sp->st_nument);
 103         }
 104
 105         sp->st_data[sp->st_top] = data;
 106 }
 107
 108 int
 109 stack_level(stk_t *sp)
 110 {
 111         return (sp->st_top + 1);
 112 }