/* 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>

 EXPORT_C  int (*sk_set_cmp_func(STACK *sk, int (*c)(const char * const *,const char * const *)))

 		(const char * const *, const char * const *)

 	{

 	int (*old)(const char * const *,const char * const *)=sk->comp;

 	if (sk->comp != c)

 		sk->sorted=0;

 	sk->comp=c;

 	return old;

 	}

 EXPORT_C 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);

 	}

 EXPORT_C STACK *sk_new_null(void)

 	{

 	return sk_new((int (*)(const char * const *, const char * const *))0);

 	}

 EXPORT_C STACK *sk_new(int (*c)(const char * const *, const char * const *))

 	{

 	STACK *ret;

 	int i;

 	if ((ret=(STACK *)OPENSSL_malloc(sizeof(STACK))) == NULL)

 		goto err;

 	if ((ret->data=(char **)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);

 	}

 EXPORT_C int sk_insert(STACK *st, char *data, int loc)

 	{

 	char **s;

 	if(st == NULL) return 0;

 	if (st->num_alloc <= st->num+1)

 		{

 		s=(char **)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=(char **)st->data;

 		t=(char **)&(st->data[1]);

 		for (i=st->num; i>=loc; i--)

 			t[i]=f[i];

 #ifdef undef /* no memmove on sunos :-( */

 		memmove( (char *)&(st->data[loc+1]),

 			(char *)&(st->data[loc]),

 			sizeof(char *)*(st->num-loc));

 #endif

 		st->data[loc]=data;

 		}

 	st->num++;

 	st->sorted=0;

 	return(st->num);

 	}

 EXPORT_C char *sk_delete_ptr(STACK *st, char *p)

 	{

 	int i;

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

 		if (st->data[i] == p)

 			return(sk_delete(st,i));

 	return(NULL);

 	}

 EXPORT_C char *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, char *data, int ret_val_options)

 	{

 	char **r;

 	int i;

 	int (*comp_func)(const void *,const void *);

 	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);

 	/* This (and the "qsort" below) are the two places in OpenSSL

 	 * where we need to convert from our standard (type **,type **)

 	 * compare callback type to the (void *,void *) type required by

 	 * bsearch. However, the "data" it is being called(back) with are

 	 * not (type *) pointers, but the *pointers* to (type *) pointers,

 	 * so we get our extra level of pointer dereferencing that way. */

 	comp_func=(int (*)(const void *,const void *))(st->comp);

 	r=(char **)OBJ_bsearch_ex((char *)&data,(char *)st->data,

 		st->num,sizeof(char *),comp_func,ret_val_options);

 	if (r == NULL) return(-1);

 	return((int)(r-st->data));

 	}

 EXPORT_C int sk_find(STACK *st, char *data)

 	{

 	return internal_find(st, data, OBJ_BSEARCH_FIRST_VALUE_ON_MATCH);

 	}

 EXPORT_C int sk_find_ex(STACK *st, char *data)

 	{

 	return internal_find(st, data, OBJ_BSEARCH_VALUE_ON_NOMATCH);

 	}

 EXPORT_C int sk_push(STACK *st, char *data)

 	{

 	return(sk_insert(st,data,st->num));

 	}

 EXPORT_C int sk_unshift(STACK *st, char *data)

 	{

 	return(sk_insert(st,data,0));

 	}

 EXPORT_C char *sk_shift(STACK *st)

 	{

 	if (st == NULL) return(NULL);

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

 	return(sk_delete(st,0));

 	}

 EXPORT_C char *sk_pop(STACK *st)

 	{

 	if (st == NULL) return(NULL);

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

 	return(sk_delete(st,st->num-1));

 	}

 EXPORT_C 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;

 	}

 EXPORT_C 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);

 	}

 EXPORT_C void sk_free(STACK *st)

 	{

 	if (st == NULL) return;

 	if (st->data != NULL) OPENSSL_free(st->data);

 	OPENSSL_free(st);

 	}

 EXPORT_C int sk_num(const STACK *st)

 {

 	if(st == NULL) return -1;

 	return st->num;

 }

 EXPORT_C char *sk_value(const STACK *st, int i)

 {

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

 	return st->data[i];

 }

 EXPORT_C char *sk_set(STACK *st, int i, char *value)

 {

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

 	return (st->data[i] = value);

 }

 EXPORT_C 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;

 		}

 	}

 EXPORT_C int sk_is_sorted(const STACK *st)

 	{

 	if (!st)

 		return 1;

 	return st->sorted;

 	}