/* 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));

 	}