/* crypto/stack/stack.c */

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * 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 (tjh@cryptsoft.com).

 *

 * 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 (eay@cryptsoft.com)"

 *    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 (tjh@cryptsoft.com)"

 *

 * 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_deep_copy(_STACK *sk, void *(*copy_func) (void *),

                     void (*free_func) (void *))

{

    _STACK *ret;

    int i;

    if ((ret = OPENSSL_malloc(sizeof(_STACK))) == NULL)

        return ret;

    ret->comp = sk->comp;

    ret->sorted = sk->sorted;

    ret->num = sk->num;

    ret->num_alloc = sk->num > MIN_NODES ? sk->num : MIN_NODES;

    ret->data = OPENSSL_malloc(sizeof(char *) * ret->num_alloc);

    if (ret->data == NULL) {

        OPENSSL_free(ret);

        return NULL;

    }

    for (i = 0; i < ret->num_alloc; i++)

        ret->data[i] = NULL;

    for (i = 0; i < ret->num; ++i) {

        if (sk->data[i] == NULL)

            continue;

        if ((ret->data[i] = copy_func(sk->data[i])) == NULL) {

            while (--i >= 0)

                if (ret->data[i] != NULL)

                    free_func(ret->data[i]);

            sk_free(ret);

            return NULL;

        }

    }

    return ret;

}

_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 && st->comp != NULL) {

        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;

}