stack.c

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/* crypto/stack/stack.c */
/* Copyright (C) 1995-1998 Eric Young ([email protected])
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young ([email protected]).
 * The implementation was written so as to conform with Netscapes SSL.
 * 
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson ([email protected]).
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * 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 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young ([email protected])"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from 
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson ([email protected])"
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 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.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

/* Code for stacks
 * Author - Eric Young v 1.0
 * 1.2 eay 12-Mar-97 -  Modified sk_find so that it _DOES_ return the
 *          lowest index for the searched item.
 *
 * 1.1 eay - Take from netdb and added to SSLeay
 *
 * 1.0 eay - First version 29/07/92
 */
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/stack.h>
#include <openssl/objects.h>

#undef MIN_NODES
#define MIN_NODES   4

const char STACK_version[]="Stack" OPENSSL_VERSION_PTEXT;

#include <errno.h>

int (*sk_set_cmp_func(_STACK *sk, int (*c)(const void *, const void *)))
        (const void *, const void *)
    {
    int (*old)(const void *,const void *)=sk->comp;

    if (sk->comp != c)
        sk->sorted=0;
    sk->comp=c;

    return old;
    }

_STACK *sk_dup(_STACK *sk)
    {
    _STACK *ret;
    char **s;

    if ((ret=sk_new(sk->comp)) == NULL) goto err;
    s=(char **)OPENSSL_realloc((char *)ret->data,
        (unsigned int)sizeof(char *)*sk->num_alloc);
    if (s == NULL) goto err;
    ret->data=s;

    ret->num=sk->num;
    memcpy(ret->data,sk->data,sizeof(char *)*sk->num);
    ret->sorted=sk->sorted;
    ret->num_alloc=sk->num_alloc;
    ret->comp=sk->comp;
    return(ret);
err:
    if(ret)
        sk_free(ret);
    return(NULL);
    }

_STACK *sk_new_null(void)
    {
    return sk_new((int (*)(const void *, const void *))0);
    }

_STACK *sk_new(int (*c)(const void *, const void *))
    {
    _STACK *ret;
    int i;

    if ((ret=OPENSSL_malloc(sizeof(_STACK))) == NULL)
        goto err;
    if ((ret->data=OPENSSL_malloc(sizeof(char *)*MIN_NODES)) == NULL)
        goto err;
    for (i=0; i<MIN_NODES; i++)
        ret->data[i]=NULL;
    ret->comp=c;
    ret->num_alloc=MIN_NODES;
    ret->num=0;
    ret->sorted=0;
    return(ret);
err:
    if(ret)
        OPENSSL_free(ret);
    return(NULL);
    }

int sk_insert(_STACK *st, void *data, int loc)
    {
    char **s;

    if(st == NULL) return 0;
    if (st->num_alloc <= st->num+1)
        {
        s=OPENSSL_realloc((char *)st->data,
            (unsigned int)sizeof(char *)*st->num_alloc*2);
        if (s == NULL)
            return(0);
        st->data=s;
        st->num_alloc*=2;
        }
    if ((loc >= (int)st->num) || (loc < 0))
        st->data[st->num]=data;
    else
        {
        int i;
        char **f,**t;

        f=st->data;
        t=&(st->data[1]);
        for (i=st->num; i>=loc; i--)
            t[i]=f[i];
            
#ifdef undef /* no memmove on sunos :-( */
        memmove(&(st->data[loc+1]),
            &(st->data[loc]),
            sizeof(char *)*(st->num-loc));
#endif
        st->data[loc]=data;
        }
    st->num++;
    st->sorted=0;
    return(st->num);
    }

void *sk_delete_ptr(_STACK *st, void *p)
    {
    int i;

    for (i=0; i<st->num; i++)
        if (st->data[i] == p)
            return(sk_delete(st,i));
    return(NULL);
    }

void *sk_delete(_STACK *st, int loc)
    {
    char *ret;
    int i,j;

    if(!st || (loc < 0) || (loc >= st->num)) return NULL;

    ret=st->data[loc];
    if (loc != st->num-1)
        {
        j=st->num-1;
        for (i=loc; i<j; i++)
            st->data[i]=st->data[i+1];
        /* In theory memcpy is not safe for this
         * memcpy( &(st->data[loc]),
         *  &(st->data[loc+1]),
         *  sizeof(char *)*(st->num-loc-1));
         */
        }
    st->num--;
    return(ret);
    }

static int internal_find(_STACK *st, void *data, int ret_val_options)
    {
    const void * const *r;
    int i;

    if(st == NULL) return -1;

    if (st->comp == NULL)
        {
        for (i=0; i<st->num; i++)
            if (st->data[i] == data)
                return(i);
        return(-1);
        }
    sk_sort(st);
    if (data == NULL) return(-1);
    r=OBJ_bsearch_ex_(&data,st->data,st->num,sizeof(void *),st->comp,
              ret_val_options);
    if (r == NULL) return(-1);
    return (int)((char **)r-st->data);
    }

int sk_find(_STACK *st, void *data)
    {
    return internal_find(st, data, OBJ_BSEARCH_FIRST_VALUE_ON_MATCH);
    }
int sk_find_ex(_STACK *st, void *data)
    {
    return internal_find(st, data, OBJ_BSEARCH_VALUE_ON_NOMATCH);
    }

int sk_push(_STACK *st, void *data)
    {
    return(sk_insert(st,data,st->num));
    }

int sk_unshift(_STACK *st, void *data)
    {
    return(sk_insert(st,data,0));
    }

void *sk_shift(_STACK *st)
    {
    if (st == NULL) return(NULL);
    if (st->num <= 0) return(NULL);
    return(sk_delete(st,0));
    }

void *sk_pop(_STACK *st)
    {
    if (st == NULL) return(NULL);
    if (st->num <= 0) return(NULL);
    return(sk_delete(st,st->num-1));
    }

void sk_zero(_STACK *st)
    {
    if (st == NULL) return;
    if (st->num <= 0) return;
    memset((char *)st->data,0,sizeof(st->data)*st->num);
    st->num=0;
    }

void sk_pop_free(_STACK *st, void (*func)(void *))
    {
    int i;

    if (st == NULL) return;
    for (i=0; i<st->num; i++)
        if (st->data[i] != NULL)
            func(st->data[i]);
    sk_free(st);
    }

void sk_free(_STACK *st)
    {
    if (st == NULL) return;
    if (st->data != NULL) OPENSSL_free(st->data);
    OPENSSL_free(st);
    }

int sk_num(const _STACK *st)
{
    if(st == NULL) return -1;
    return st->num;
}

void *sk_value(const _STACK *st, int i)
{
    if(!st || (i < 0) || (i >= st->num)) return NULL;
    return st->data[i];
}

void *sk_set(_STACK *st, int i, void *value)
{
    if(!st || (i < 0) || (i >= st->num)) return NULL;
    return (st->data[i] = value);
}

void sk_sort(_STACK *st)
    {
    if (st && !st->sorted)
        {
        int (*comp_func)(const void *,const void *);

        /* same comment as in sk_find ... previously st->comp was declared
         * as a (void*,void*) callback type, but this made the population
         * of the callback pointer illogical - our callbacks compare
         * type** with type**, so we leave the casting until absolutely
         * necessary (ie. "now"). */
        comp_func=(int (*)(const void *,const void *))(st->comp);
        qsort(st->data,st->num,sizeof(char *), comp_func);
        st->sorted=1;
        }
    }

int sk_is_sorted(const _STACK *st)
    {
    if (!st)
        return 1;
    return st->sorted;
    }