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			125 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			125 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * mbuf.h
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|  *		Memory buffer operations.
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|  *
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|  * Copyright (c) 2005 Marko Kreen
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|  * All rights reserved.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions
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|  * are met:
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|  * 1. Redistributions of source code must retain the above copyright
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|  *	  notice, this list of conditions and the following disclaimer.
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|  * 2. Redistributions in binary form must reproduce the above copyright
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|  *	  notice, this list of conditions and the following disclaimer in the
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|  *	  documentation and/or other materials provided with the distribution.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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|  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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|  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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|  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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|  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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|  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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|  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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|  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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|  * SUCH DAMAGE.
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|  *
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|  * contrib/pgcrypto/mbuf.h
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|  */
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| 
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| #ifndef __PX_MBUF_H
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| #define __PX_MBUF_H
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| 
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| typedef struct MBuf MBuf;
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| typedef struct PushFilter PushFilter;
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| typedef struct PullFilter PullFilter;
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| typedef struct PushFilterOps PushFilterOps;
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| typedef struct PullFilterOps PullFilterOps;
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| 
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| struct PushFilterOps
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| {
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| 	/*
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| 	 * should return needed buffer size, 0- no buffering, <0 on error if NULL,
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| 	 * no buffering, and priv=init_arg
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| 	 */
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| 	int			(*init) (PushFilter *next, void *init_arg, void **priv_p);
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| 
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| 	/*
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| 	 * send data to next.  should consume all? if null, it will be simply
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| 	 * copied (in-place) returns 0 on error
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| 	 */
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| 	int			(*push) (PushFilter *next, void *priv,
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| 									 const uint8 *src, int len);
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| 	int			(*flush) (PushFilter *next, void *priv);
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| 	void		(*free) (void *priv);
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| };
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| 
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| struct PullFilterOps
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| {
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| 	/*
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| 	 * should return needed buffer size, 0- no buffering, <0 on error if NULL,
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| 	 * no buffering, and priv=init_arg
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| 	 */
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| 	int			(*init) (void **priv_p, void *init_arg, PullFilter *src);
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| 
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| 	/*
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| 	 * request data from src, put result ptr to data_p can use ptr from src or
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| 	 * use buf as work area if NULL in-place copy
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| 	 */
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| 	int			(*pull) (void *priv, PullFilter *src, int len,
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| 									 uint8 **data_p, uint8 *buf, int buflen);
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| 	void		(*free) (void *priv);
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| };
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| 
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| /*
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|  * Memory buffer
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|  */
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| MBuf	   *mbuf_create(int len);
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| MBuf	   *mbuf_create_from_data(uint8 *data, int len);
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| int			mbuf_tell(MBuf *mbuf);
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| int			mbuf_avail(MBuf *mbuf);
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| int			mbuf_size(MBuf *mbuf);
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| int			mbuf_grab(MBuf *mbuf, int len, uint8 **data_p);
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| int			mbuf_steal_data(MBuf *mbuf, uint8 **data_p);
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| int			mbuf_append(MBuf *dst, const uint8 *buf, int cnt);
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| int			mbuf_rewind(MBuf *mbuf);
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| int			mbuf_free(MBuf *mbuf);
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| 
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| /*
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|  * Push filter
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|  */
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| int pushf_create(PushFilter **res, const PushFilterOps *ops, void *init_arg,
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| 			 PushFilter *next);
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| int			pushf_write(PushFilter *mp, const uint8 *data, int len);
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| void		pushf_free_all(PushFilter *mp);
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| void		pushf_free(PushFilter *mp);
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| int			pushf_flush(PushFilter *mp);
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| 
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| int			pushf_create_mbuf_writer(PushFilter **mp_p, MBuf *mbuf);
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| 
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| /*
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|  * Pull filter
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|  */
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| int pullf_create(PullFilter **res, const PullFilterOps *ops,
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| 			 void *init_arg, PullFilter *src);
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| int			pullf_read(PullFilter *mp, int len, uint8 **data_p);
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| int pullf_read_max(PullFilter *mp, int len,
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| 			   uint8 **data_p, uint8 *tmpbuf);
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| void		pullf_free(PullFilter *mp);
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| int			pullf_read_fixed(PullFilter *src, int len, uint8 *dst);
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| 
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| int			pullf_create_mbuf_reader(PullFilter **pf_p, MBuf *mbuf);
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| 
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| #define GETBYTE(pf, dst) \
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| 	do { \
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| 		uint8 __b; \
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| 		int __res = pullf_read_fixed(pf, 1, &__b); \
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| 		if (__res < 0) \
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| 			return __res; \
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| 		(dst) = __b; \
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| 	} while (0)
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| 
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| #endif   /* __PX_MBUF_H */
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