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http://git.haproxy.org/git/haproxy.git/
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dab5ab551d
The functions channel_htx_fwd_payload() and channel_htx_fwd_all() should now be used to forward, respectively, a part of the HTX payload or all of it. These functions forward data and update the first block position.
1053 lines
34 KiB
C
1053 lines
34 KiB
C
/*
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* include/proto/channel.h
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* Channel management definitions, macros and inline functions.
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*
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* Copyright (C) 2000-2014 Willy Tarreau - w@1wt.eu
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation, version 2.1
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* exclusively.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef _PROTO_CHANNEL_H
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#define _PROTO_CHANNEL_H
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#include <inttypes.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <common/config.h>
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#include <common/chunk.h>
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#include <common/htx.h>
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#include <common/ticks.h>
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#include <common/time.h>
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#include <types/channel.h>
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#include <types/global.h>
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#include <types/stream.h>
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#include <types/stream_interface.h>
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#include <proto/stream.h>
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#include <proto/task.h>
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/* perform minimal intializations, report 0 in case of error, 1 if OK. */
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int init_channel();
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unsigned long long __channel_forward(struct channel *chn, unsigned long long bytes);
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/* SI-to-channel functions working with buffers */
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int ci_putblk(struct channel *chn, const char *str, int len);
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int ci_putchr(struct channel *chn, char c);
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int ci_getline_nc(const struct channel *chn, char **blk1, size_t *len1, char **blk2, size_t *len2);
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int ci_getblk_nc(const struct channel *chn, char **blk1, size_t *len1, char **blk2, size_t *len2);
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int ci_insert_line2(struct channel *c, int pos, const char *str, int len);
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int co_inject(struct channel *chn, const char *msg, int len);
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int co_getline(const struct channel *chn, char *str, int len);
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int co_getblk(const struct channel *chn, char *blk, int len, int offset);
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int co_getline_nc(const struct channel *chn, const char **blk1, size_t *len1, const char **blk2, size_t *len2);
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int co_getblk_nc(const struct channel *chn, const char **blk1, size_t *len1, const char **blk2, size_t *len2);
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/* returns a pointer to the stream the channel belongs to */
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static inline struct stream *chn_strm(const struct channel *chn)
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{
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if (chn->flags & CF_ISRESP)
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return LIST_ELEM(chn, struct stream *, res);
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else
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return LIST_ELEM(chn, struct stream *, req);
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}
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/* returns a pointer to the stream interface feeding the channel (producer) */
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static inline struct stream_interface *chn_prod(const struct channel *chn)
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{
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if (chn->flags & CF_ISRESP)
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return &LIST_ELEM(chn, struct stream *, res)->si[1];
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else
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return &LIST_ELEM(chn, struct stream *, req)->si[0];
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}
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/* returns a pointer to the stream interface consuming the channel (producer) */
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static inline struct stream_interface *chn_cons(const struct channel *chn)
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{
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if (chn->flags & CF_ISRESP)
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return &LIST_ELEM(chn, struct stream *, res)->si[0];
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else
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return &LIST_ELEM(chn, struct stream *, req)->si[1];
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}
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/* c_orig() : returns the pointer to the channel buffer's origin */
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static inline char *c_orig(const struct channel *c)
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{
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return b_orig(&c->buf);
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}
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/* c_size() : returns the size of the channel's buffer */
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static inline size_t c_size(const struct channel *c)
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{
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return b_size(&c->buf);
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}
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/* c_wrap() : returns the pointer to the channel buffer's wrapping point */
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static inline char *c_wrap(const struct channel *c)
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{
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return b_wrap(&c->buf);
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}
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/* c_data() : returns the amount of data in the channel's buffer */
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static inline size_t c_data(const struct channel *c)
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{
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return b_data(&c->buf);
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}
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/* c_room() : returns the room left in the channel's buffer */
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static inline size_t c_room(const struct channel *c)
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{
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return b_size(&c->buf) - b_data(&c->buf);
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}
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/* c_empty() : returns a boolean indicating if the channel's buffer is empty */
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static inline size_t c_empty(const struct channel *c)
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{
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return !c_data(c);
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}
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/* c_full() : returns a boolean indicating if the channel's buffer is full */
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static inline size_t c_full(const struct channel *c)
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{
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return !c_room(c);
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}
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/* co_data() : returns the amount of output data in the channel's buffer */
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static inline size_t co_data(const struct channel *c)
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{
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return c->output;
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}
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/* ci_data() : returns the amount of input data in the channel's buffer */
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static inline size_t ci_data(const struct channel *c)
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{
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return c_data(c) - co_data(c);
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}
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/* ci_next() : for an absolute pointer <p> or a relative offset <o> pointing to
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* a valid location within channel <c>'s buffer, returns either the absolute
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* pointer or the relative offset pointing to the next byte, which usually is
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* at (p + 1) unless p reaches the wrapping point and wrapping is needed.
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*/
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static inline size_t ci_next_ofs(const struct channel *c, size_t o)
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{
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return b_next_ofs(&c->buf, o);
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}
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static inline char *ci_next(const struct channel *c, const char *p)
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{
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return b_next(&c->buf, p);
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}
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/* c_ptr() : returns a pointer to an offset relative to the beginning of the
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* input data in the buffer. If instead the offset is negative, a pointer to
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* existing output data is returned. The function only takes care of wrapping,
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* it's up to the caller to ensure the offset is always within byte count
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* bounds.
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*/
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static inline char *c_ptr(const struct channel *c, ssize_t ofs)
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{
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return b_peek(&c->buf, co_data(c) + ofs);
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}
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/* c_adv() : advances the channel's buffer by <adv> bytes, which means that the
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* buffer's pointer advances, and that as many bytes from in are transferred
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* from in to out. The caller is responsible for ensuring that adv is always
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* smaller than or equal to b->i.
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*/
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static inline void c_adv(struct channel *c, size_t adv)
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{
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c->output += adv;
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}
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/* c_rew() : rewinds the channel's buffer by <adv> bytes, which means that the
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* buffer's pointer goes backwards, and that as many bytes from out are moved
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* to in. The caller is responsible for ensuring that adv is always smaller
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* than or equal to b->o.
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*/
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static inline void c_rew(struct channel *c, size_t adv)
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{
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c->output -= adv;
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}
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/* c_realign_if_empty() : realign the channel's buffer if it's empty */
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static inline void c_realign_if_empty(struct channel *chn)
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{
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b_realign_if_empty(&chn->buf);
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}
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/* Sets the amount of output for the channel */
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static inline void co_set_data(struct channel *c, size_t output)
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{
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c->output = output;
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}
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/* co_head() : returns a pointer to the beginning of output data in the buffer.
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* The "__" variants don't support wrapping, "ofs" are relative to
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* the buffer's origin.
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*/
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static inline size_t __co_head_ofs(const struct channel *c)
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{
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return __b_peek_ofs(&c->buf, 0);
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}
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static inline char *__co_head(const struct channel *c)
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{
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return __b_peek(&c->buf, 0);
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}
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static inline size_t co_head_ofs(const struct channel *c)
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{
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return b_peek_ofs(&c->buf, 0);
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}
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static inline char *co_head(const struct channel *c)
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{
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return b_peek(&c->buf, 0);
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}
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/* co_tail() : returns a pointer to the end of output data in the buffer.
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* The "__" variants don't support wrapping, "ofs" are relative to
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* the buffer's origin.
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*/
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static inline size_t __co_tail_ofs(const struct channel *c)
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{
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return __b_peek_ofs(&c->buf, co_data(c));
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}
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static inline char *__co_tail(const struct channel *c)
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{
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return __b_peek(&c->buf, co_data(c));
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}
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static inline size_t co_tail_ofs(const struct channel *c)
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{
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return b_peek_ofs(&c->buf, co_data(c));
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}
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static inline char *co_tail(const struct channel *c)
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{
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return b_peek(&c->buf, co_data(c));
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}
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/* ci_head() : returns a pointer to the beginning of input data in the buffer.
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* The "__" variants don't support wrapping, "ofs" are relative to
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* the buffer's origin.
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*/
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static inline size_t __ci_head_ofs(const struct channel *c)
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{
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return __b_peek_ofs(&c->buf, co_data(c));
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}
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static inline char *__ci_head(const struct channel *c)
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{
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return __b_peek(&c->buf, co_data(c));
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}
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static inline size_t ci_head_ofs(const struct channel *c)
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{
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return b_peek_ofs(&c->buf, co_data(c));
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}
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static inline char *ci_head(const struct channel *c)
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{
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return b_peek(&c->buf, co_data(c));
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}
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/* ci_tail() : returns a pointer to the end of input data in the buffer.
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* The "__" variants don't support wrapping, "ofs" are relative to
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* the buffer's origin.
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*/
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static inline size_t __ci_tail_ofs(const struct channel *c)
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{
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return __b_peek_ofs(&c->buf, c_data(c));
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}
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static inline char *__ci_tail(const struct channel *c)
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{
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return __b_peek(&c->buf, c_data(c));
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}
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static inline size_t ci_tail_ofs(const struct channel *c)
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{
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return b_peek_ofs(&c->buf, c_data(c));
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}
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static inline char *ci_tail(const struct channel *c)
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{
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return b_peek(&c->buf, c_data(c));
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}
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/* ci_stop() : returns the pointer to the byte following the end of input data
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* in the channel buffer. It may be out of the buffer. It's used to
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* compute lengths or stop pointers.
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*/
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static inline size_t __ci_stop_ofs(const struct channel *c)
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{
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return __b_stop_ofs(&c->buf);
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}
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static inline const char *__ci_stop(const struct channel *c)
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{
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return __b_stop(&c->buf);
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}
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static inline size_t ci_stop_ofs(const struct channel *c)
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{
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return b_stop_ofs(&c->buf);
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}
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static inline const char *ci_stop(const struct channel *c)
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{
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return b_stop(&c->buf);
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}
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/* Returns the amount of input data that can contiguously be read at once */
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static inline size_t ci_contig_data(const struct channel *c)
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{
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return b_contig_data(&c->buf, co_data(c));
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}
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/* Initialize all fields in the channel. */
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static inline void channel_init(struct channel *chn)
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{
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chn->buf = BUF_NULL;
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chn->to_forward = 0;
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chn->last_read = now_ms;
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chn->xfer_small = chn->xfer_large = 0;
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chn->total = 0;
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chn->pipe = NULL;
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chn->analysers = 0;
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chn->flags = 0;
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chn->output = 0;
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}
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/* Schedule up to <bytes> more bytes to be forwarded via the channel without
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* notifying the owner task. Any data pending in the buffer are scheduled to be
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* sent as well, in the limit of the number of bytes to forward. This must be
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* the only method to use to schedule bytes to be forwarded. If the requested
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* number is too large, it is automatically adjusted. The number of bytes taken
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* into account is returned. Directly touching ->to_forward will cause lockups
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* when buf->o goes down to zero if nobody is ready to push the remaining data.
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*/
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static inline unsigned long long channel_forward(struct channel *chn, unsigned long long bytes)
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{
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/* hint: avoid comparisons on long long for the fast case, since if the
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* length does not fit in an unsigned it, it will never be forwarded at
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* once anyway.
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*/
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if (bytes <= ~0U) {
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unsigned int bytes32 = bytes;
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if (bytes32 <= ci_data(chn)) {
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/* OK this amount of bytes might be forwarded at once */
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c_adv(chn, bytes32);
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return bytes;
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}
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}
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return __channel_forward(chn, bytes);
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}
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/* Forwards any input data and marks the channel for permanent forwarding */
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static inline void channel_forward_forever(struct channel *chn)
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{
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c_adv(chn, ci_data(chn));
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chn->to_forward = CHN_INFINITE_FORWARD;
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}
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/* <len> bytes of input data was added into the channel <chn>. This functions
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* must be called to update the channel state. It also handles the fast
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* forwarding. */
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static inline void channel_add_input(struct channel *chn, unsigned int len)
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{
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if (chn->to_forward) {
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unsigned long fwd = len;
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if (chn->to_forward != CHN_INFINITE_FORWARD) {
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if (fwd > chn->to_forward)
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fwd = chn->to_forward;
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chn->to_forward -= fwd;
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}
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c_adv(chn, fwd);
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}
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/* notify that some data was read */
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chn->total += len;
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chn->flags |= CF_READ_PARTIAL;
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}
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static inline unsigned long long channel_htx_forward(struct channel *chn, struct htx *htx, unsigned long long bytes)
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{
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unsigned long long ret;
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b_set_data(&chn->buf, htx->data);
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ret = channel_forward(chn, bytes);
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b_set_data(&chn->buf, b_size(&chn->buf));
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return ret;
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}
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static inline void channel_htx_forward_forever(struct channel *chn, struct htx *htx)
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{
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b_set_data(&chn->buf, htx->data);
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channel_forward_forever(chn);
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b_set_data(&chn->buf, b_size(&chn->buf));
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}
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/*********************************************************************/
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/* These functions are used to compute various channel content sizes */
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/*********************************************************************/
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/* Reports non-zero if the channel is empty, which means both its
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* buffer and pipe are empty. The construct looks strange but is
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* jump-less and much more efficient on both 32 and 64-bit than
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* the boolean test.
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*/
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static inline unsigned int channel_is_empty(const struct channel *c)
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{
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return !(co_data(c) | (long)c->pipe);
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}
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/* Returns non-zero if the channel is rewritable, which means that the buffer
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* it is attached to has at least <maxrewrite> bytes immediately available.
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* This is used to decide when a request or response may be parsed when some
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* data from a previous exchange might still be present.
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*/
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static inline int channel_is_rewritable(const struct channel *chn)
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{
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int rem = chn->buf.size;
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rem -= b_data(&chn->buf);
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rem -= global.tune.maxrewrite;
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return rem >= 0;
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}
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/* Tells whether data are likely to leave the buffer. This is used to know when
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* we can safely ignore the reserve since we know we cannot retry a connection.
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* It returns zero if data are blocked, non-zero otherwise.
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*/
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static inline int channel_may_send(const struct channel *chn)
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{
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return chn_cons(chn)->state == SI_ST_EST;
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}
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/* Returns non-zero if the channel can still receive data. This is used to
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* decide when to stop reading into a buffer when we want to ensure that we
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* leave the reserve untouched after all pending outgoing data are forwarded.
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* The reserved space is taken into account if ->to_forward indicates that an
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* end of transfer is close to happen. Note that both ->buf.o and ->to_forward
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* are considered as available since they're supposed to leave the buffer. The
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* test is optimized to avoid as many operations as possible for the fast case
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* and to be used as an "if" condition. Just like channel_recv_limit(), we
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* never allow to overwrite the reserve until the output stream interface is
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* connected, otherwise we could spin on a POST with http-send-name-header.
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*/
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static inline int channel_may_recv(const struct channel *chn)
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{
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int rem = chn->buf.size;
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if (b_is_null(&chn->buf))
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return 1;
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rem -= b_data(&chn->buf);
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if (!rem)
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return 0; /* buffer already full */
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if (rem > global.tune.maxrewrite)
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return 1; /* reserve not yet reached */
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if (!channel_may_send(chn))
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return 0; /* don't touch reserve until we can send */
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/* Now we know there's some room left in the reserve and we may
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* forward. As long as i-to_fwd < size-maxrw, we may still
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* receive. This is equivalent to i+maxrw-size < to_fwd,
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* which is logical since i+maxrw-size is what overlaps with
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* the reserve, and we want to ensure they're covered by scheduled
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* forwards.
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*/
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rem = ci_data(chn) + global.tune.maxrewrite - chn->buf.size;
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return rem < 0 || (unsigned int)rem < chn->to_forward;
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}
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/* HTX version of channel_may_recv(). Returns non-zero if the channel can still
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* receive data. */
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static inline int channel_htx_may_recv(const struct channel *chn, const struct htx *htx)
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{
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uint32_t rem;
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if (!htx->size)
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return 1;
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if (!channel_may_send(chn))
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return 0; /* don't touch reserve until we can send */
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|
|
rem = htx_free_data_space(htx);
|
|
if (!rem)
|
|
return 0; /* htx already full */
|
|
|
|
if (rem > global.tune.maxrewrite)
|
|
return 1; /* reserve not yet reached */
|
|
|
|
/* Now we know there's some room left in the reserve and we may
|
|
* forward. As long as i-to_fwd < size-maxrw, we may still
|
|
* receive. This is equivalent to i+maxrw-size < to_fwd,
|
|
* which is logical since i+maxrw-size is what overlaps with
|
|
* the reserve, and we want to ensure they're covered by scheduled
|
|
* forwards.
|
|
*/
|
|
rem += co_data(chn);
|
|
if (rem > global.tune.maxrewrite)
|
|
return 1;
|
|
|
|
return (global.tune.maxrewrite - rem < chn->to_forward);
|
|
}
|
|
|
|
/* Returns true if the channel's input is already closed */
|
|
static inline int channel_input_closed(struct channel *chn)
|
|
{
|
|
return ((chn->flags & CF_SHUTR) != 0);
|
|
}
|
|
|
|
/* Returns true if the channel's output is already closed */
|
|
static inline int channel_output_closed(struct channel *chn)
|
|
{
|
|
return ((chn->flags & CF_SHUTW) != 0);
|
|
}
|
|
|
|
/* Check channel timeouts, and set the corresponding flags. The likely/unlikely
|
|
* have been optimized for fastest normal path. The read/write timeouts are not
|
|
* set if there was activity on the channel. That way, we don't have to update
|
|
* the timeout on every I/O. Note that the analyser timeout is always checked.
|
|
*/
|
|
static inline void channel_check_timeouts(struct channel *chn)
|
|
{
|
|
if (likely(!(chn->flags & (CF_SHUTR|CF_READ_TIMEOUT|CF_READ_ACTIVITY|CF_READ_NOEXP))) &&
|
|
unlikely(tick_is_expired(chn->rex, now_ms)))
|
|
chn->flags |= CF_READ_TIMEOUT;
|
|
|
|
if (likely(!(chn->flags & (CF_SHUTW|CF_WRITE_TIMEOUT|CF_WRITE_ACTIVITY))) &&
|
|
unlikely(tick_is_expired(chn->wex, now_ms)))
|
|
chn->flags |= CF_WRITE_TIMEOUT;
|
|
|
|
if (likely(!(chn->flags & CF_ANA_TIMEOUT)) &&
|
|
unlikely(tick_is_expired(chn->analyse_exp, now_ms)))
|
|
chn->flags |= CF_ANA_TIMEOUT;
|
|
}
|
|
|
|
/* Erase any content from channel <buf> and adjusts flags accordingly. Note
|
|
* that any spliced data is not affected since we may not have any access to
|
|
* it.
|
|
*/
|
|
static inline void channel_erase(struct channel *chn)
|
|
{
|
|
chn->to_forward = 0;
|
|
chn->output = 0;
|
|
b_reset(&chn->buf);
|
|
}
|
|
|
|
static inline void channel_htx_erase(struct channel *chn, struct htx *htx)
|
|
{
|
|
htx_reset(htx);
|
|
channel_erase(chn);
|
|
}
|
|
|
|
/* marks the channel as "shutdown" ASAP for reads */
|
|
static inline void channel_shutr_now(struct channel *chn)
|
|
{
|
|
chn->flags |= CF_SHUTR_NOW;
|
|
}
|
|
|
|
/* marks the channel as "shutdown" ASAP for writes */
|
|
static inline void channel_shutw_now(struct channel *chn)
|
|
{
|
|
chn->flags |= CF_SHUTW_NOW;
|
|
}
|
|
|
|
/* marks the channel as "shutdown" ASAP in both directions */
|
|
static inline void channel_abort(struct channel *chn)
|
|
{
|
|
chn->flags |= CF_SHUTR_NOW | CF_SHUTW_NOW;
|
|
chn->flags &= ~CF_AUTO_CONNECT;
|
|
}
|
|
|
|
/* allow the consumer to try to establish a new connection. */
|
|
static inline void channel_auto_connect(struct channel *chn)
|
|
{
|
|
chn->flags |= CF_AUTO_CONNECT;
|
|
}
|
|
|
|
/* prevent the consumer from trying to establish a new connection, and also
|
|
* disable auto shutdown forwarding.
|
|
*/
|
|
static inline void channel_dont_connect(struct channel *chn)
|
|
{
|
|
chn->flags &= ~(CF_AUTO_CONNECT|CF_AUTO_CLOSE);
|
|
}
|
|
|
|
/* allow the producer to forward shutdown requests */
|
|
static inline void channel_auto_close(struct channel *chn)
|
|
{
|
|
chn->flags |= CF_AUTO_CLOSE;
|
|
}
|
|
|
|
/* prevent the producer from forwarding shutdown requests */
|
|
static inline void channel_dont_close(struct channel *chn)
|
|
{
|
|
chn->flags &= ~CF_AUTO_CLOSE;
|
|
}
|
|
|
|
/* allow the producer to read / poll the input */
|
|
static inline void channel_auto_read(struct channel *chn)
|
|
{
|
|
chn->flags &= ~CF_DONT_READ;
|
|
}
|
|
|
|
/* prevent the producer from read / poll the input */
|
|
static inline void channel_dont_read(struct channel *chn)
|
|
{
|
|
chn->flags |= CF_DONT_READ;
|
|
}
|
|
|
|
|
|
/*************************************************/
|
|
/* Buffer operations in the context of a channel */
|
|
/*************************************************/
|
|
|
|
|
|
/* Return the max number of bytes the buffer can contain so that once all the
|
|
* pending bytes are forwarded, the buffer still has global.tune.maxrewrite
|
|
* bytes free. The result sits between chn->size - maxrewrite and chn->size.
|
|
* It is important to mention that if buf->i is already larger than size-maxrw
|
|
* the condition above cannot be satisfied and the lowest size will be returned
|
|
* anyway. The principles are the following :
|
|
* 0) the empty buffer has a limit of zero
|
|
* 1) a non-connected buffer cannot touch the reserve
|
|
* 2) infinite forward can always fill the buffer since all data will leave
|
|
* 3) all output bytes are considered in transit since they're leaving
|
|
* 4) all input bytes covered by to_forward are considered in transit since
|
|
* they'll be converted to output bytes.
|
|
* 5) all input bytes not covered by to_forward as considered remaining
|
|
* 6) all bytes scheduled to be forwarded minus what is already in the input
|
|
* buffer will be in transit during future rounds.
|
|
* 7) 4+5+6 imply that the amount of input bytes (i) is irrelevant to the max
|
|
* usable length, only to_forward and output count. The difference is
|
|
* visible when to_forward > i.
|
|
* 8) the reserve may be covered up to the amount of bytes in transit since
|
|
* these bytes will only take temporary space.
|
|
*
|
|
* A typical buffer looks like this :
|
|
*
|
|
* <-------------- max_len ----------->
|
|
* <---- o ----><----- i -----> <--- 0..maxrewrite --->
|
|
* +------------+--------------+-------+----------------------+
|
|
* |////////////|\\\\\\\\\\\\\\|xxxxxxx| reserve |
|
|
* +------------+--------+-----+-------+----------------------+
|
|
* <- fwd -> <-avail->
|
|
*
|
|
* Or when to_forward > i :
|
|
*
|
|
* <-------------- max_len ----------->
|
|
* <---- o ----><----- i -----> <--- 0..maxrewrite --->
|
|
* +------------+--------------+-------+----------------------+
|
|
* |////////////|\\\\\\\\\\\\\\|xxxxxxx| reserve |
|
|
* +------------+--------+-----+-------+----------------------+
|
|
* <-avail->
|
|
* <------------------ fwd ---------------->
|
|
*
|
|
* - the amount of buffer bytes in transit is : min(i, fwd) + o
|
|
* - some scheduled bytes may be in transit (up to fwd - i)
|
|
* - the reserve is max(0, maxrewrite - transit)
|
|
* - the maximum usable buffer length is size - reserve.
|
|
* - the available space is max_len - i - o
|
|
*
|
|
* So the formula to compute the buffer's maximum length to protect the reserve
|
|
* when reading new data is :
|
|
*
|
|
* max = size - maxrewrite + min(maxrewrite, transit)
|
|
* = size - max(maxrewrite - transit, 0)
|
|
*
|
|
* But WARNING! The conditions might change during the transfer and it could
|
|
* very well happen that a buffer would contain more bytes than max_len due to
|
|
* i+o already walking over the reserve (eg: after a header rewrite), including
|
|
* i or o alone hitting the limit. So it is critical to always consider that
|
|
* bounds may have already been crossed and that available space may be negative
|
|
* for example. Due to this it is perfectly possible for this function to return
|
|
* a value that is lower than current i+o.
|
|
*/
|
|
static inline int channel_recv_limit(const struct channel *chn)
|
|
{
|
|
unsigned int transit;
|
|
int reserve;
|
|
|
|
/* return zero if empty */
|
|
reserve = chn->buf.size;
|
|
if (b_is_null(&chn->buf))
|
|
goto end;
|
|
|
|
/* return size - maxrewrite if we can't send */
|
|
reserve = global.tune.maxrewrite;
|
|
if (unlikely(!channel_may_send(chn)))
|
|
goto end;
|
|
|
|
/* We need to check what remains of the reserve after o and to_forward
|
|
* have been transmitted, but they can overflow together and they can
|
|
* cause an integer underflow in the comparison since both are unsigned
|
|
* while maxrewrite is signed.
|
|
* The code below has been verified for being a valid check for this :
|
|
* - if (o + to_forward) overflow => return size [ large enough ]
|
|
* - if o + to_forward >= maxrw => return size [ large enough ]
|
|
* - otherwise return size - (maxrw - (o + to_forward))
|
|
*/
|
|
transit = co_data(chn) + chn->to_forward;
|
|
reserve -= transit;
|
|
if (transit < chn->to_forward || // addition overflow
|
|
transit >= (unsigned)global.tune.maxrewrite) // enough transit data
|
|
return chn->buf.size;
|
|
end:
|
|
return chn->buf.size - reserve;
|
|
}
|
|
|
|
/* HTX version of channel_recv_limit(). Return the max number of bytes the HTX
|
|
* buffer can contain so that once all the pending bytes are forwarded, the
|
|
* buffer still has global.tune.maxrewrite bytes free.
|
|
*/
|
|
static inline int channel_htx_recv_limit(const struct channel *chn, const struct htx *htx)
|
|
{
|
|
unsigned int transit;
|
|
int reserve;
|
|
|
|
/* return zeor if not allocated */
|
|
if (!htx->size)
|
|
return 0;
|
|
|
|
/* return max_data_space - maxrewrite if we can't send */
|
|
reserve = global.tune.maxrewrite;
|
|
if (unlikely(!channel_may_send(chn)))
|
|
goto end;
|
|
|
|
/* We need to check what remains of the reserve after o and to_forward
|
|
* have been transmitted, but they can overflow together and they can
|
|
* cause an integer underflow in the comparison since both are unsigned
|
|
* while maxrewrite is signed.
|
|
* The code below has been verified for being a valid check for this :
|
|
* - if (o + to_forward) overflow => return max_data_space [ large enough ]
|
|
* - if o + to_forward >= maxrw => return max_data_space [ large enough ]
|
|
* - otherwise return max_data_space - (maxrw - (o + to_forward))
|
|
*/
|
|
transit = co_data(chn) + chn->to_forward;
|
|
reserve -= transit;
|
|
if (transit < chn->to_forward || // addition overflow
|
|
transit >= (unsigned)global.tune.maxrewrite) // enough transit data
|
|
return htx_max_data_space(htx);
|
|
end:
|
|
return (htx_max_data_space(htx) - reserve);
|
|
}
|
|
|
|
/* Returns non-zero if the channel's INPUT buffer's is considered full, which
|
|
* means that it holds at least as much INPUT data as (size - reserve). This
|
|
* also means that data that are scheduled for output are considered as potential
|
|
* free space, and that the reserved space is always considered as not usable.
|
|
* This information alone cannot be used as a general purpose free space indicator.
|
|
* However it accurately indicates that too many data were fed in the buffer
|
|
* for an analyzer for instance. See the channel_may_recv() function for a more
|
|
* generic function taking everything into account.
|
|
*/
|
|
static inline int channel_full(const struct channel *c, unsigned int reserve)
|
|
{
|
|
if (b_is_null(&c->buf))
|
|
return 0;
|
|
|
|
return (ci_data(c) + reserve >= c_size(c));
|
|
}
|
|
|
|
/* HTX version of channel_full(). Instead of checking if INPUT data exceeds
|
|
* (size - reserve), this function checks if the free space for data in <htx>
|
|
* and the data scheduled for output are lower to the reserve. In such case, the
|
|
* channel is considered as full.
|
|
*/
|
|
static inline int channel_htx_full(const struct channel *c, const struct htx *htx,
|
|
unsigned int reserve)
|
|
{
|
|
if (!htx->size)
|
|
return 0;
|
|
return (htx_free_data_space(htx) + co_data(c) <= reserve);
|
|
}
|
|
|
|
|
|
/* HTX version of channel_recv_max(). */
|
|
static inline int channel_htx_recv_max(const struct channel *chn, const struct htx *htx)
|
|
{
|
|
int ret;
|
|
|
|
ret = channel_htx_recv_limit(chn, htx) - htx_used_space(htx);
|
|
if (ret < 0)
|
|
ret = 0;
|
|
return ret;
|
|
}
|
|
|
|
/* Returns the amount of space available at the input of the buffer, taking the
|
|
* reserved space into account if ->to_forward indicates that an end of transfer
|
|
* is close to happen. The test is optimized to avoid as many operations as
|
|
* possible for the fast case.
|
|
*/
|
|
static inline int channel_recv_max(const struct channel *chn)
|
|
{
|
|
int ret;
|
|
|
|
if (IS_HTX_STRM(chn_strm(chn)))
|
|
return channel_htx_recv_max(chn, htxbuf(&chn->buf));
|
|
|
|
ret = channel_recv_limit(chn) - b_data(&chn->buf);
|
|
if (ret < 0)
|
|
ret = 0;
|
|
return ret;
|
|
}
|
|
|
|
/* Returns the amount of bytes that can be written over the input data at once,
|
|
* including reserved space which may be overwritten. This is used by Lua to
|
|
* insert data in the input side just before the other data using buffer_replace().
|
|
* The goal is to transfer these new data in the output buffer.
|
|
*/
|
|
static inline int ci_space_for_replace(const struct channel *chn)
|
|
{
|
|
const struct buffer *buf = &chn->buf;
|
|
const char *end;
|
|
|
|
/* If the input side data overflows, we cannot insert data contiguously. */
|
|
if (b_head(buf) + b_data(buf) >= b_wrap(buf))
|
|
return 0;
|
|
|
|
/* Check the last byte used in the buffer, it may be a byte of the output
|
|
* side if the buffer wraps, or its the end of the buffer.
|
|
*/
|
|
end = b_head(buf);
|
|
if (end <= ci_head(chn))
|
|
end = b_wrap(buf);
|
|
|
|
/* Compute the amount of bytes which can be written. */
|
|
return end - ci_tail(chn);
|
|
}
|
|
|
|
/* Allocates a buffer for channel <chn>, but only if it's guaranteed that it's
|
|
* not the last available buffer or it's the response buffer. Unless the buffer
|
|
* is the response buffer, an extra control is made so that we always keep
|
|
* <tune.buffers.reserved> buffers available after this allocation. Returns 0 in
|
|
* case of failure, non-zero otherwise.
|
|
*
|
|
* If no buffer are available, the requester, represented by <wait> pointer,
|
|
* will be added in the list of objects waiting for an available buffer.
|
|
*/
|
|
static inline int channel_alloc_buffer(struct channel *chn, struct buffer_wait *wait)
|
|
{
|
|
int margin = 0;
|
|
|
|
if (!(chn->flags & CF_ISRESP))
|
|
margin = global.tune.reserved_bufs;
|
|
|
|
if (b_alloc_margin(&chn->buf, margin) != NULL)
|
|
return 1;
|
|
|
|
if (LIST_ISEMPTY(&wait->list)) {
|
|
HA_SPIN_LOCK(BUF_WQ_LOCK, &buffer_wq_lock);
|
|
LIST_ADDQ(&buffer_wq, &wait->list);
|
|
HA_SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Releases a possibly allocated buffer for channel <chn>. If it was not
|
|
* allocated, this function does nothing. Else the buffer is released and we try
|
|
* to wake up as many streams/applets as possible. */
|
|
static inline void channel_release_buffer(struct channel *chn, struct buffer_wait *wait)
|
|
{
|
|
if (c_size(chn) && c_empty(chn)) {
|
|
b_free(&chn->buf);
|
|
offer_buffers(wait->target, tasks_run_queue);
|
|
}
|
|
}
|
|
|
|
/* Truncate any unread data in the channel's buffer, and disable forwarding.
|
|
* Outgoing data are left intact. This is mainly to be used to send error
|
|
* messages after existing data.
|
|
*/
|
|
static inline void channel_truncate(struct channel *chn)
|
|
{
|
|
if (!co_data(chn))
|
|
return channel_erase(chn);
|
|
|
|
chn->to_forward = 0;
|
|
if (!ci_data(chn))
|
|
return;
|
|
|
|
chn->buf.data = co_data(chn);
|
|
}
|
|
|
|
static inline void channel_htx_truncate(struct channel *chn, struct htx *htx)
|
|
{
|
|
if (!co_data(chn))
|
|
return channel_htx_erase(chn, htx);
|
|
|
|
chn->to_forward = 0;
|
|
if (htx->data == co_data(chn))
|
|
return;
|
|
htx_truncate(htx, co_data(chn));
|
|
}
|
|
|
|
/* This function realigns a possibly wrapping channel buffer so that the input
|
|
* part is contiguous and starts at the beginning of the buffer and the output
|
|
* part ends at the end of the buffer. This provides the best conditions since
|
|
* it allows the largest inputs to be processed at once and ensures that once
|
|
* the output data leaves, the whole buffer is available at once.
|
|
*/
|
|
static inline void channel_slow_realign(struct channel *chn, char *swap)
|
|
{
|
|
return b_slow_realign(&chn->buf, swap, co_data(chn));
|
|
}
|
|
|
|
|
|
/* Forward all headers of an HTX message, starting from the SL to the EOH. This
|
|
* function also updates the first block position.
|
|
*/
|
|
static inline void channel_htx_fwd_headers(struct channel *chn, struct htx *htx)
|
|
{
|
|
int32_t pos;
|
|
size_t data = 0;
|
|
|
|
for (pos = htx_get_first(htx); pos != -1; pos = htx_get_next(htx, pos)) {
|
|
struct htx_blk *blk = htx_get_blk(htx, pos);
|
|
data += htx_get_blksz(blk);
|
|
if (htx_get_blk_type(blk) == HTX_BLK_EOH) {
|
|
htx->first = htx_get_next(htx, pos);
|
|
break;
|
|
}
|
|
}
|
|
c_adv(chn, data);
|
|
}
|
|
|
|
/* Forward <data> bytes of payload of an HTX message. This function also updates
|
|
* the first block position.
|
|
*/
|
|
static inline void channel_htx_fwd_payload(struct channel *chn, struct htx *htx, size_t data)
|
|
{
|
|
int32_t pos;
|
|
|
|
c_adv(chn, data);
|
|
for (pos = htx_get_first(htx); pos != -1; pos = htx_get_next(htx, pos)) {
|
|
uint32_t sz = htx_get_blksz(htx_get_blk(htx, pos));
|
|
|
|
if (data < sz)
|
|
break;
|
|
data -= sz;
|
|
}
|
|
htx->first = pos;
|
|
}
|
|
|
|
/* Forward all data of an HTX message. This function also updates the first
|
|
* block position.
|
|
*/
|
|
static inline void channel_htx_fwd_all(struct channel *chn, struct htx *htx)
|
|
{
|
|
htx->first = -1;
|
|
c_adv(chn, htx->data - co_data(chn));
|
|
}
|
|
|
|
/*
|
|
* Advance the channel buffer's read pointer by <len> bytes. This is useful
|
|
* when data have been read directly from the buffer. It is illegal to call
|
|
* this function with <len> causing a wrapping at the end of the buffer. It's
|
|
* the caller's responsibility to ensure that <len> is never larger than
|
|
* chn->o. Channel flags WRITE_PARTIAL and WROTE_DATA are set.
|
|
*/
|
|
static inline void co_skip(struct channel *chn, int len)
|
|
{
|
|
b_del(&chn->buf, len);
|
|
chn->output -= len;
|
|
c_realign_if_empty(chn);
|
|
|
|
/* notify that some data was written to the SI from the buffer */
|
|
chn->flags |= CF_WRITE_PARTIAL | CF_WROTE_DATA;
|
|
}
|
|
|
|
/* HTX version of co_skip(). This function skips at most <len> bytes from the
|
|
* output of the channel <chn>. Depending on how data are stored in <htx> less
|
|
* than <len> bytes can be skipped. Channel flags WRITE_PARTIAL and WROTE_DATA
|
|
* are set.
|
|
*/
|
|
static inline void co_htx_skip(struct channel *chn, struct htx *htx, int len)
|
|
{
|
|
struct htx_ret htxret;
|
|
|
|
htxret = htx_drain(htx, len);
|
|
if (htxret.ret) {
|
|
chn->output -= htxret.ret;
|
|
|
|
/* notify that some data was written to the SI from the buffer */
|
|
chn->flags |= CF_WRITE_PARTIAL | CF_WROTE_DATA;
|
|
}
|
|
}
|
|
|
|
/* Tries to copy chunk <chunk> into the channel's buffer after length controls.
|
|
* The chn->o and to_forward pointers are updated. If the channel's input is
|
|
* closed, -2 is returned. If the block is too large for this buffer, -3 is
|
|
* returned. If there is not enough room left in the buffer, -1 is returned.
|
|
* Otherwise the number of bytes copied is returned (0 being a valid number).
|
|
* Channel flag READ_PARTIAL is updated if some data can be transferred. The
|
|
* chunk's length is updated with the number of bytes sent.
|
|
*/
|
|
static inline int ci_putchk(struct channel *chn, struct buffer *chunk)
|
|
{
|
|
int ret;
|
|
|
|
ret = ci_putblk(chn, chunk->area, chunk->data);
|
|
if (ret > 0)
|
|
chunk->data -= ret;
|
|
return ret;
|
|
}
|
|
|
|
/* Tries to copy string <str> at once into the channel's buffer after length
|
|
* controls. The chn->o and to_forward pointers are updated. If the channel's
|
|
* input is closed, -2 is returned. If the block is too large for this buffer,
|
|
* -3 is returned. If there is not enough room left in the buffer, -1 is
|
|
* returned. Otherwise the number of bytes copied is returned (0 being a valid
|
|
* number). Channel flag READ_PARTIAL is updated if some data can be
|
|
* transferred.
|
|
*/
|
|
static inline int ci_putstr(struct channel *chn, const char *str)
|
|
{
|
|
return ci_putblk(chn, str, strlen(str));
|
|
}
|
|
|
|
/*
|
|
* Return one char from the channel's buffer. If the buffer is empty and the
|
|
* channel is closed, return -2. If the buffer is just empty, return -1. The
|
|
* buffer's pointer is not advanced, it's up to the caller to call co_skip(buf,
|
|
* 1) when it has consumed the char. Also note that this function respects the
|
|
* chn->o limit.
|
|
*/
|
|
static inline int co_getchr(struct channel *chn)
|
|
{
|
|
/* closed or empty + imminent close = -2; empty = -1 */
|
|
if (unlikely((chn->flags & CF_SHUTW) || channel_is_empty(chn))) {
|
|
if (chn->flags & (CF_SHUTW|CF_SHUTW_NOW))
|
|
return -2;
|
|
return -1;
|
|
}
|
|
return *co_head(chn);
|
|
}
|
|
|
|
|
|
#endif /* _PROTO_CHANNEL_H */
|
|
|
|
/*
|
|
* Local variables:
|
|
* c-indent-level: 8
|
|
* c-basic-offset: 8
|
|
* End:
|
|
*/
|