/* crypto/bio/bf_nbio.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.]

 */

#include <stdio.h>

#include <errno.h>

#include "cryptlib.h"

#include <openssl/rand.h>

#include <openssl/bio.h>

/* BIO_put and BIO_get both add to the digest,

 * BIO_gets returns the digest */

static int nbiof_write(BIO *h,const char *buf,int num);

static int nbiof_read(BIO *h,char *buf,int size);

static int nbiof_puts(BIO *h,const char *str);

static int nbiof_gets(BIO *h,char *str,int size);

static long nbiof_ctrl(BIO *h,int cmd,long arg1,void *arg2);

static int nbiof_new(BIO *h);

static int nbiof_free(BIO *data);

static long nbiof_callback_ctrl(BIO *h,int cmd,bio_info_cb *fp);

typedef struct nbio_test_st

	{

	/* only set if we sent a 'should retry' error */

	int lrn;

	int lwn;

	} NBIO_TEST;

static BIO_METHOD methods_nbiof=

	{

	BIO_TYPE_NBIO_TEST,

	"non-blocking IO test filter",

	nbiof_write,

	nbiof_read,

	nbiof_puts,

	nbiof_gets,

	nbiof_ctrl,

	nbiof_new,

	nbiof_free,

	nbiof_callback_ctrl,

	};

EXPORT_C BIO_METHOD *BIO_f_nbio_test(void)

	{

	return(&methods_nbiof);

	}

static int nbiof_new(BIO *bi)

	{

	NBIO_TEST *nt;

	if (!(nt=(NBIO_TEST *)OPENSSL_malloc(sizeof(NBIO_TEST)))) return(0);

	nt->lrn= -1;

	nt->lwn= -1;

	bi->ptr=(char *)nt;

	bi->init=1;

	bi->flags=0;

	return(1);

	}

static int nbiof_free(BIO *a)

	{

	if (a == NULL) return(0);

	if (a->ptr != NULL)

		OPENSSL_free(a->ptr);

	a->ptr=NULL;

	a->init=0;

	a->flags=0;

	return(1);

	}

static int nbiof_read(BIO *b, char *out, int outl)

	{

	NBIO_TEST *nt;

	int ret=0;

#if 1

	int num;

	unsigned char n;

#endif

	if (out == NULL) return(0);

	if (b->next_bio == NULL) return(0);

	nt=(NBIO_TEST *)b->ptr;

	BIO_clear_retry_flags(b);

#if 1

	RAND_pseudo_bytes(&n,1);

	num=(n&0x07);

	if (outl > num) outl=num;

	if (num == 0)

		{

		ret= -1;

		BIO_set_retry_read(b);

		}

	else

#endif

		{

		ret=BIO_read(b->next_bio,out,outl);

		if (ret < 0)

			BIO_copy_next_retry(b);

		}

	return(ret);

	}

static int nbiof_write(BIO *b, const char *in, int inl)

	{

	NBIO_TEST *nt;

	int ret=0;

	int num;

	unsigned char n;

	if ((in == NULL) || (inl <= 0)) return(0);

	if (b->next_bio == NULL) return(0);

	nt=(NBIO_TEST *)b->ptr;

	BIO_clear_retry_flags(b);

#if 1

	if (nt->lwn > 0)

		{

		num=nt->lwn;

		nt->lwn=0;

		}

	else

		{

		RAND_pseudo_bytes(&n,1);

		num=(n&7);

		}

	if (inl > num) inl=num;

	if (num == 0)

		{

		ret= -1;

		BIO_set_retry_write(b);

		}

	else

#endif

		{

		ret=BIO_write(b->next_bio,in,inl);

		if (ret < 0)

			{

			BIO_copy_next_retry(b);

			nt->lwn=inl;

			}

		}

	return(ret);

	}

static long nbiof_ctrl(BIO *b, int cmd, long num, void *ptr)

	{

	long ret;

	if (b->next_bio == NULL) return(0);

	switch (cmd)

		{

        case BIO_C_DO_STATE_MACHINE:

		BIO_clear_retry_flags(b);

		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

		BIO_copy_next_retry(b);

		break;

	case BIO_CTRL_DUP:

		ret=0L;

		break;

	default:

		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

		break;

		}

	return(ret);

	}

static long nbiof_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)

	{

	long ret=1;

	if (b->next_bio == NULL) return(0);

	switch (cmd)

		{

	default:

		ret=BIO_callback_ctrl(b->next_bio,cmd,fp);

		break;

		}

	return(ret);

	}

static int nbiof_gets(BIO *bp, char *buf, int size)

	{

	if (bp->next_bio == NULL) return(0);

	return(BIO_gets(bp->next_bio,buf,size));

	}

static int nbiof_puts(BIO *bp, const char *str)

	{

	if (bp->next_bio == NULL) return(0);

	return(BIO_puts(bp->next_bio,str));

	}