/* crypto/bio/bf_buff.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/bio.h>

#include <openssl/evp.h>

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

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

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

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

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

static int linebuffer_new(BIO *h);

static int linebuffer_free(BIO *data);

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

/* A 10k maximum should be enough for most purposes */

#define DEFAULT_LINEBUFFER_SIZE	1024*10

/* #define DEBUG */

static BIO_METHOD methods_linebuffer=

	{

	BIO_TYPE_LINEBUFFER,

	"linebuffer",

	linebuffer_write,

	linebuffer_read,

	linebuffer_puts,

	linebuffer_gets,

	linebuffer_ctrl,

	linebuffer_new,

	linebuffer_free,

	linebuffer_callback_ctrl,

	};

BIO_METHOD *BIO_f_linebuffer(void)

	{

	return(&methods_linebuffer);

	}

typedef struct bio_linebuffer_ctx_struct

	{

	char *obuf;		/* the output char array */

	int obuf_size;		/* how big is the output buffer */

	int obuf_len;		/* how many bytes are in it */

	} BIO_LINEBUFFER_CTX;

static int linebuffer_new(BIO *bi)

	{

	BIO_LINEBUFFER_CTX *ctx;

	ctx=(BIO_LINEBUFFER_CTX *)OPENSSL_malloc(sizeof(BIO_LINEBUFFER_CTX));

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

	ctx->obuf=(char *)OPENSSL_malloc(DEFAULT_LINEBUFFER_SIZE);

	if (ctx->obuf == NULL) { OPENSSL_free(ctx); return(0); }

	ctx->obuf_size=DEFAULT_LINEBUFFER_SIZE;

	ctx->obuf_len=0;

	bi->init=1;

	bi->ptr=(char *)ctx;

	bi->flags=0;

	return(1);

	}

static int linebuffer_free(BIO *a)

	{

	BIO_LINEBUFFER_CTX *b;

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

	b=(BIO_LINEBUFFER_CTX *)a->ptr;

	if (b->obuf != NULL) OPENSSL_free(b->obuf);

	OPENSSL_free(a->ptr);

	a->ptr=NULL;

	a->init=0;

	a->flags=0;

	return(1);

	}

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

	{

	int ret=0;

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

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

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

	BIO_clear_retry_flags(b);

	BIO_copy_next_retry(b);

	return(ret);

	}

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

	{

	int i,num=0,foundnl;

	BIO_LINEBUFFER_CTX *ctx;

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

	ctx=(BIO_LINEBUFFER_CTX *)b->ptr;

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

	BIO_clear_retry_flags(b);

	do

		{

		const char *p;

		for(p = in; p < in + inl && *p != '\n'; p++)

			;

		if (*p == '\n')

			{

			p++;

			foundnl = 1;

			}

		else

			foundnl = 0;

		/* If a NL was found and we already have text in the save

		   buffer, concatenate them and write */

		while ((foundnl || p - in > ctx->obuf_size - ctx->obuf_len)

			&& ctx->obuf_len > 0)

			{

			int orig_olen = ctx->obuf_len;

			i = ctx->obuf_size - ctx->obuf_len;

			if (p - in > 0)

				{

				if (i >= p - in)

					{

					memcpy(&(ctx->obuf[ctx->obuf_len]),

						in,p - in);

					ctx->obuf_len += p - in;

					inl -= p - in;

					num += p - in;

					in = p;

					}

				else

					{

					memcpy(&(ctx->obuf[ctx->obuf_len]),

						in,i);

					ctx->obuf_len += i;

					inl -= i;

					in += i;

					num += i;

					}

				}

#if 0

BIO_write(b->next_bio, "<*<", 3);

#endif

			i=BIO_write(b->next_bio,

				ctx->obuf, ctx->obuf_len);

			if (i <= 0)

				{

				ctx->obuf_len = orig_olen;

				BIO_copy_next_retry(b);

#if 0

BIO_write(b->next_bio, ">*>", 3);

#endif

				if (i < 0) return((num > 0)?num:i);

				if (i == 0) return(num);

				}

#if 0

BIO_write(b->next_bio, ">*>", 3);

#endif

			if (i < ctx->obuf_len)

				memmove(ctx->obuf, ctx->obuf + i,

					ctx->obuf_len - i);

			ctx->obuf_len-=i;

			}

		/* Now that the save buffer is emptied, let's write the input

		   buffer if a NL was found and there is anything to write. */

		if ((foundnl || p - in > ctx->obuf_size) && p - in > 0)

			{

#if 0

BIO_write(b->next_bio, "<*<", 3);

#endif

			i=BIO_write(b->next_bio,in,p - in);

			if (i <= 0)

				{

				BIO_copy_next_retry(b);

#if 0

BIO_write(b->next_bio, ">*>", 3);

#endif

				if (i < 0) return((num > 0)?num:i);

				if (i == 0) return(num);

				}

#if 0

BIO_write(b->next_bio, ">*>", 3);

#endif

			num+=i;

			in+=i;

			inl-=i;

			}

		}

	while(foundnl && inl > 0);

	/* We've written as much as we can.  The rest of the input buffer, if

	   any, is text that doesn't and with a NL and therefore needs to be

	   saved for the next trip. */

	if (inl > 0)

		{

		memcpy(&(ctx->obuf[ctx->obuf_len]), in, inl);

		ctx->obuf_len += inl;

		num += inl;

		}

	return num;

	}

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

	{

	BIO *dbio;

	BIO_LINEBUFFER_CTX *ctx;

	long ret=1;

	char *p;

	int r;

	int obs;

	ctx=(BIO_LINEBUFFER_CTX *)b->ptr;

	switch (cmd)

		{

	case BIO_CTRL_RESET:

		ctx->obuf_len=0;

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

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

		break;

	case BIO_CTRL_INFO:

		ret=(long)ctx->obuf_len;

		break;

	case BIO_CTRL_WPENDING:

		ret=(long)ctx->obuf_len;

		if (ret == 0)

			{

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

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

			}

		break;

	case BIO_C_SET_BUFF_SIZE:

		obs=(int)num;

		p=ctx->obuf;

		if ((obs > DEFAULT_LINEBUFFER_SIZE) && (obs != ctx->obuf_size))

			{

			p=(char *)OPENSSL_malloc((int)num);

			if (p == NULL)

				goto malloc_error;

			}

		if (ctx->obuf != p)

			{

			if (ctx->obuf_len > obs)

				{

				ctx->obuf_len = obs;

				}

			memcpy(p, ctx->obuf, ctx->obuf_len);

			OPENSSL_free(ctx->obuf);

			ctx->obuf=p;

			ctx->obuf_size=obs;

			}

		break;

	case BIO_C_DO_STATE_MACHINE:

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

		BIO_clear_retry_flags(b);

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

		BIO_copy_next_retry(b);

		break;

	case BIO_CTRL_FLUSH:

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

		if (ctx->obuf_len <= 0)

			{

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

			break;

			}

		for (;;)

			{

			BIO_clear_retry_flags(b);

			if (ctx->obuf_len > 0)

				{

				r=BIO_write(b->next_bio,

					ctx->obuf, ctx->obuf_len);

#if 0

fprintf(stderr,"FLUSH %3d -> %3d\n",ctx->obuf_len,r);

#endif

				BIO_copy_next_retry(b);

				if (r <= 0) return((long)r);

				if (r < ctx->obuf_len)

					memmove(ctx->obuf, ctx->obuf + r,

						ctx->obuf_len - r);

				ctx->obuf_len-=r;

				}

			else

				{

				ctx->obuf_len=0;

				ret=1;

				break;

				}

			}

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

		break;

	case BIO_CTRL_DUP:

		dbio=(BIO *)ptr;

		if (	!BIO_set_write_buffer_size(dbio,ctx->obuf_size))

			ret=0;

		break;

	default:

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

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

		break;

		}

	return(ret);

malloc_error:

	BIOerr(BIO_F_LINEBUFFER_CTRL,ERR_R_MALLOC_FAILURE);

	return(0);

	}

static long linebuffer_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 linebuffer_gets(BIO *b, char *buf, int size)

	{

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

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

	}

static int linebuffer_puts(BIO *b, const char *str)

	{

	return(linebuffer_write(b,str,strlen(str)));

	}