mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-12-03 08:00:21 +08:00
125 lines
4.0 KiB
C
125 lines
4.0 KiB
C
/*
|
|
* mbuf.h
|
|
* Memory buffer operations.
|
|
*
|
|
* Copyright (c) 2005 Marko Kreen
|
|
* All rights reserved.
|
|
*
|
|
* 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 above 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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.
|
|
*
|
|
* $PostgreSQL: pgsql/contrib/pgcrypto/mbuf.h,v 1.2 2005/10/15 02:49:06 momjian Exp $
|
|
*/
|
|
|
|
#ifndef __PX_MBUF_H
|
|
#define __PX_MBUF_H
|
|
|
|
typedef struct MBuf MBuf;
|
|
typedef struct PushFilter PushFilter;
|
|
typedef struct PullFilter PullFilter;
|
|
typedef struct PushFilterOps PushFilterOps;
|
|
typedef struct PullFilterOps PullFilterOps;
|
|
|
|
struct PushFilterOps
|
|
{
|
|
/*
|
|
* should return needed buffer size, 0- no buffering, <0 on error if NULL,
|
|
* no buffering, and priv=init_arg
|
|
*/
|
|
int (*init) (PushFilter * next, void *init_arg, void **priv_p);
|
|
|
|
/*
|
|
* send data to next. should consume all? if null, it will be simply
|
|
* copied (in-place) returns 0 on error
|
|
*/
|
|
int (*push) (PushFilter * next, void *priv,
|
|
const uint8 *src, int len);
|
|
int (*flush) (PushFilter * next, void *priv);
|
|
void (*free) (void *priv);
|
|
};
|
|
|
|
struct PullFilterOps
|
|
{
|
|
/*
|
|
* should return needed buffer size, 0- no buffering, <0 on error if NULL,
|
|
* no buffering, and priv=init_arg
|
|
*/
|
|
int (*init) (void **priv_p, void *init_arg, PullFilter * src);
|
|
|
|
/*
|
|
* request data from src, put result ptr to data_p can use ptr from src or
|
|
* use buf as work area if NULL in-place copy
|
|
*/
|
|
int (*pull) (void *priv, PullFilter * src, int len,
|
|
uint8 **data_p, uint8 *buf, int buflen);
|
|
void (*free) (void *priv);
|
|
};
|
|
|
|
/*
|
|
* Memory buffer
|
|
*/
|
|
MBuf *mbuf_create(int len);
|
|
MBuf *mbuf_create_from_data(const uint8 *data, int len);
|
|
int mbuf_tell(MBuf * mbuf);
|
|
int mbuf_avail(MBuf * mbuf);
|
|
int mbuf_size(MBuf * mbuf);
|
|
int mbuf_grab(MBuf * mbuf, int len, uint8 **data_p);
|
|
int mbuf_steal_data(MBuf * mbuf, uint8 **data_p);
|
|
int mbuf_append(MBuf * dst, const uint8 *buf, int cnt);
|
|
int mbuf_rewind(MBuf * mbuf);
|
|
int mbuf_free(MBuf * mbuf);
|
|
|
|
/*
|
|
* Push filter
|
|
*/
|
|
int pushf_create(PushFilter ** res, const PushFilterOps * ops, void *init_arg,
|
|
PushFilter * next);
|
|
int pushf_write(PushFilter * mp, const uint8 *data, int len);
|
|
void pushf_free_all(PushFilter * mp);
|
|
void pushf_free(PushFilter * mp);
|
|
int pushf_flush(PushFilter * mp);
|
|
|
|
int pushf_create_mbuf_writer(PushFilter ** mp_p, MBuf * mbuf);
|
|
|
|
/*
|
|
* Pull filter
|
|
*/
|
|
int pullf_create(PullFilter ** res, const PullFilterOps * ops,
|
|
void *init_arg, PullFilter * src);
|
|
int pullf_read(PullFilter * mp, int len, uint8 **data_p);
|
|
int pullf_read_max(PullFilter * mp, int len,
|
|
uint8 **data_p, uint8 *tmpbuf);
|
|
void pullf_free(PullFilter * mp);
|
|
int pullf_read_fixed(PullFilter * src, int len, uint8 *dst);
|
|
|
|
int pullf_create_mbuf_reader(PullFilter ** pf_p, MBuf * mbuf);
|
|
|
|
#define GETBYTE(pf, dst) \
|
|
do { \
|
|
uint8 __b; \
|
|
int __res = pullf_read_fixed(pf, 1, &__b); \
|
|
if (__res < 0) \
|
|
return __res; \
|
|
(dst) = __b; \
|
|
} while (0)
|
|
|
|
#endif /* __PX_MBUF_H */
|