Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 1 | /* |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 2 | * include/proto/channel.h |
| 3 | * Channel management definitions, macros and inline functions. |
Willy Tarreau | 7c3c541 | 2009-12-13 15:53:05 +0100 | [diff] [blame] | 4 | * |
Willy Tarreau | 9dab5fc | 2012-05-07 11:56:55 +0200 | [diff] [blame] | 5 | * Copyright (C) 2000-2012 Willy Tarreau - w@1wt.eu |
Willy Tarreau | 7c3c541 | 2009-12-13 15:53:05 +0100 | [diff] [blame] | 6 | * |
| 7 | * This library is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation, version 2.1 |
| 10 | * exclusively. |
| 11 | * |
| 12 | * This library is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with this library; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 21 | |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 22 | #ifndef _PROTO_CHANNEL_H |
| 23 | #define _PROTO_CHANNEL_H |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 24 | |
Willy Tarreau | 7341d94 | 2007-05-13 19:56:02 +0200 | [diff] [blame] | 25 | #include <stdio.h> |
Willy Tarreau | 0f77253 | 2006-12-23 20:51:41 +0100 | [diff] [blame] | 26 | #include <stdlib.h> |
Willy Tarreau | 7341d94 | 2007-05-13 19:56:02 +0200 | [diff] [blame] | 27 | #include <string.h> |
Willy Tarreau | 0f77253 | 2006-12-23 20:51:41 +0100 | [diff] [blame] | 28 | |
Willy Tarreau | e3ba5f0 | 2006-06-29 18:54:54 +0200 | [diff] [blame] | 29 | #include <common/config.h> |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 30 | #include <common/chunk.h> |
Willy Tarreau | 7341d94 | 2007-05-13 19:56:02 +0200 | [diff] [blame] | 31 | #include <common/memory.h> |
Willy Tarreau | 0c303ee | 2008-07-07 00:09:58 +0200 | [diff] [blame] | 32 | #include <common/ticks.h> |
Willy Tarreau | fa64558 | 2007-06-03 15:59:52 +0200 | [diff] [blame] | 33 | #include <common/time.h> |
| 34 | |
Willy Tarreau | 7c3c541 | 2009-12-13 15:53:05 +0100 | [diff] [blame] | 35 | #include <types/global.h> |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 36 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 37 | extern struct pool_head *pool2_channel; |
Willy Tarreau | 7341d94 | 2007-05-13 19:56:02 +0200 | [diff] [blame] | 38 | |
| 39 | /* perform minimal intializations, report 0 in case of error, 1 if OK. */ |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 40 | int init_channel(); |
Willy Tarreau | 7341d94 | 2007-05-13 19:56:02 +0200 | [diff] [blame] | 41 | |
Willy Tarreau | 55a6906 | 2012-10-26 00:21:52 +0200 | [diff] [blame] | 42 | unsigned long long __channel_forward(struct channel *chn, unsigned long long bytes); |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 43 | |
| 44 | /* SI-to-channel functions working with buffers */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 45 | int bi_putblk(struct channel *chn, const char *str, int len); |
| 46 | int bi_putchr(struct channel *chn, char c); |
| 47 | int bo_inject(struct channel *chn, const char *msg, int len); |
| 48 | int bo_getline(struct channel *chn, char *str, int len); |
| 49 | int bo_getblk(struct channel *chn, char *blk, int len, int offset); |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 50 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 51 | /* Initialize all fields in the channel. */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 52 | static inline void channel_init(struct channel *chn) |
Willy Tarreau | 5446940 | 2006-07-29 16:59:06 +0200 | [diff] [blame] | 53 | { |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 54 | chn->buf->o = 0; |
| 55 | chn->buf->i = 0; |
| 56 | chn->buf->p = chn->buf->data; |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 57 | chn->to_forward = 0; |
Willy Tarreau | b145c78 | 2014-02-09 17:45:16 +0100 | [diff] [blame] | 58 | chn->last_read = now_ms; |
Willy Tarreau | 8f39dcd | 2014-02-09 08:31:49 +0100 | [diff] [blame] | 59 | chn->xfer_small = chn->xfer_large = 0; |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 60 | chn->total = 0; |
| 61 | chn->pipe = NULL; |
| 62 | chn->analysers = 0; |
| 63 | chn->cons = NULL; |
| 64 | chn->flags = 0; |
Willy Tarreau | 5446940 | 2006-07-29 16:59:06 +0200 | [diff] [blame] | 65 | } |
| 66 | |
Willy Tarreau | 55a6906 | 2012-10-26 00:21:52 +0200 | [diff] [blame] | 67 | /* Schedule up to <bytes> more bytes to be forwarded via the channel without |
| 68 | * notifying the owner task. Any data pending in the buffer are scheduled to be |
| 69 | * sent as well, in the limit of the number of bytes to forward. This must be |
| 70 | * the only method to use to schedule bytes to be forwarded. If the requested |
| 71 | * number is too large, it is automatically adjusted. The number of bytes taken |
| 72 | * into account is returned. Directly touching ->to_forward will cause lockups |
| 73 | * when buf->o goes down to zero if nobody is ready to push the remaining data. |
| 74 | */ |
| 75 | static inline unsigned long long channel_forward(struct channel *chn, unsigned long long bytes) |
| 76 | { |
| 77 | /* hint: avoid comparisons on long long for the fast case, since if the |
| 78 | * length does not fit in an unsigned it, it will never be forwarded at |
| 79 | * once anyway. |
| 80 | */ |
| 81 | if (bytes <= ~0U) { |
| 82 | unsigned int bytes32 = bytes; |
| 83 | |
| 84 | if (bytes32 <= chn->buf->i) { |
| 85 | /* OK this amount of bytes might be forwarded at once */ |
| 86 | b_adv(chn->buf, bytes32); |
| 87 | return bytes; |
| 88 | } |
| 89 | } |
| 90 | return __channel_forward(chn, bytes); |
| 91 | } |
| 92 | |
Willy Tarreau | 7460212 | 2016-05-04 14:05:58 +0200 | [diff] [blame] | 93 | /* Forwards any input data and marks the channel for permanent forwarding */ |
| 94 | static inline void channel_forward_forever(struct channel *chn) |
| 95 | { |
| 96 | b_adv(chn->buf, chn->buf->i); |
| 97 | chn->to_forward = CHN_INFINITE_FORWARD; |
| 98 | } |
| 99 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 100 | /*********************************************************************/ |
| 101 | /* These functions are used to compute various channel content sizes */ |
| 102 | /*********************************************************************/ |
Willy Tarreau | 4b517ca | 2011-11-25 20:33:58 +0100 | [diff] [blame] | 103 | |
Willy Tarreau | 8e21bb9 | 2012-08-24 22:40:29 +0200 | [diff] [blame] | 104 | /* Reports non-zero if the channel is empty, which means both its |
| 105 | * buffer and pipe are empty. The construct looks strange but is |
| 106 | * jump-less and much more efficient on both 32 and 64-bit than |
| 107 | * the boolean test. |
| 108 | */ |
| 109 | static inline unsigned int channel_is_empty(struct channel *c) |
| 110 | { |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 111 | return !(c->buf->o | (long)c->pipe); |
Willy Tarreau | 8e21bb9 | 2012-08-24 22:40:29 +0200 | [diff] [blame] | 112 | } |
| 113 | |
Willy Tarreau | 379357a | 2013-06-08 12:55:46 +0200 | [diff] [blame] | 114 | /* Returns non-zero if the buffer input has all of its reserve available. This |
| 115 | * is used to decide when a request or response may be parsed when some data |
| 116 | * from a previous exchange might still be present. |
| 117 | */ |
| 118 | static inline int channel_reserved(const struct channel *chn) |
| 119 | { |
| 120 | int rem = chn->buf->size; |
| 121 | |
| 122 | rem -= chn->buf->o; |
| 123 | rem -= chn->buf->i; |
| 124 | rem -= global.tune.maxrewrite; |
| 125 | return rem >= 0; |
| 126 | } |
| 127 | |
Willy Tarreau | 9f905d9 | 2016-05-02 16:05:10 +0200 | [diff] [blame] | 128 | /* Returns non-zero if the channel is congested with data in transit waiting |
| 129 | * for leaving, indicating to the caller that it should wait for the reserve to |
| 130 | * be released before starting to process new data in case it needs the ability |
| 131 | * to append data. This is meant to be used while waiting for a clean response |
| 132 | * buffer before processing a request. |
| 133 | */ |
| 134 | static inline int channel_congested(const struct channel *chn) |
| 135 | { |
| 136 | if (!chn->buf->o) |
| 137 | return 0; |
| 138 | |
| 139 | if (!channel_reserved(chn)) |
| 140 | return 1; |
| 141 | |
| 142 | if (chn->buf->p + chn->buf->i > |
| 143 | chn->buf->data + chn->buf->size - global.tune.maxrewrite) |
| 144 | return 1; |
| 145 | |
| 146 | return 0; |
| 147 | } |
| 148 | |
Willy Tarreau | ca12910 | 2015-01-14 16:08:45 +0100 | [diff] [blame] | 149 | /* Tells whether data are likely to leave the buffer. This is used to know when |
| 150 | * we can safely ignore the reserve since we know we cannot retry a connection. |
| 151 | * It returns zero if data are blocked, non-zero otherwise. |
| 152 | */ |
| 153 | static inline int channel_may_send(const struct channel *chn) |
| 154 | { |
| 155 | return chn->cons->state == SI_ST_EST; |
| 156 | } |
| 157 | |
Willy Tarreau | 379357a | 2013-06-08 12:55:46 +0200 | [diff] [blame] | 158 | /* Returns non-zero if the buffer input is considered full. This is used to |
| 159 | * decide when to stop reading into a buffer when we want to ensure that we |
| 160 | * leave the reserve untouched after all pending outgoing data are forwarded. |
| 161 | * The reserved space is taken into account if ->to_forward indicates that an |
| 162 | * end of transfer is close to happen. Note that both ->buf->o and ->to_forward |
| 163 | * are considered as available since they're supposed to leave the buffer. The |
| 164 | * test is optimized to avoid as many operations as possible for the fast case |
Willy Tarreau | c3981fc | 2016-04-20 20:09:22 +0200 | [diff] [blame] | 165 | * and to be used as an "if" condition. Just like channel_recv_limit(), we |
| 166 | * never allow to overwrite the reserve until the output stream interface is |
| 167 | * connected, otherwise we could spin on a POST with http-send-name-header. |
Willy Tarreau | 4b517ca | 2011-11-25 20:33:58 +0100 | [diff] [blame] | 168 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 169 | static inline int channel_full(const struct channel *chn) |
Willy Tarreau | 4b517ca | 2011-11-25 20:33:58 +0100 | [diff] [blame] | 170 | { |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 171 | int rem = chn->buf->size; |
Willy Tarreau | 9dab5fc | 2012-05-07 11:56:55 +0200 | [diff] [blame] | 172 | |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 173 | rem -= chn->buf->o; |
| 174 | rem -= chn->buf->i; |
Willy Tarreau | 9dab5fc | 2012-05-07 11:56:55 +0200 | [diff] [blame] | 175 | if (!rem) |
| 176 | return 1; /* buffer already full */ |
| 177 | |
Willy Tarreau | fdc90ca | 2016-04-21 12:12:45 +0200 | [diff] [blame] | 178 | if (rem > global.tune.maxrewrite) |
| 179 | return 0; |
Willy Tarreau | c3981fc | 2016-04-20 20:09:22 +0200 | [diff] [blame] | 180 | |
Willy Tarreau | fdc90ca | 2016-04-21 12:12:45 +0200 | [diff] [blame] | 181 | if (!channel_may_send(chn)) |
| 182 | return 1; |
Willy Tarreau | 9dab5fc | 2012-05-07 11:56:55 +0200 | [diff] [blame] | 183 | |
Willy Tarreau | fdc90ca | 2016-04-21 12:12:45 +0200 | [diff] [blame] | 184 | rem = chn->buf->i + global.tune.maxrewrite - chn->buf->size; |
| 185 | return rem >= 0 && (unsigned int)rem >= chn->to_forward; |
Willy Tarreau | 4b517ca | 2011-11-25 20:33:58 +0100 | [diff] [blame] | 186 | } |
| 187 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 188 | /* Returns true if the channel's input is already closed */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 189 | static inline int channel_input_closed(struct channel *chn) |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 190 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 191 | return ((chn->flags & CF_SHUTR) != 0); |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 192 | } |
| 193 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 194 | /* Returns true if the channel's output is already closed */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 195 | static inline int channel_output_closed(struct channel *chn) |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 196 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 197 | return ((chn->flags & CF_SHUTW) != 0); |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 198 | } |
| 199 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 200 | /* Check channel timeouts, and set the corresponding flags. The likely/unlikely |
| 201 | * have been optimized for fastest normal path. The read/write timeouts are not |
| 202 | * set if there was activity on the channel. That way, we don't have to update |
| 203 | * the timeout on every I/O. Note that the analyser timeout is always checked. |
Willy Tarreau | 2eb52f0 | 2008-09-04 09:14:08 +0200 | [diff] [blame] | 204 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 205 | static inline void channel_check_timeouts(struct channel *chn) |
Willy Tarreau | 2eb52f0 | 2008-09-04 09:14:08 +0200 | [diff] [blame] | 206 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 207 | if (likely(!(chn->flags & (CF_SHUTR|CF_READ_TIMEOUT|CF_READ_ACTIVITY|CF_READ_NOEXP))) && |
| 208 | unlikely(tick_is_expired(chn->rex, now_ms))) |
| 209 | chn->flags |= CF_READ_TIMEOUT; |
Willy Tarreau | 2eb52f0 | 2008-09-04 09:14:08 +0200 | [diff] [blame] | 210 | |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 211 | if (likely(!(chn->flags & (CF_SHUTW|CF_WRITE_TIMEOUT|CF_WRITE_ACTIVITY))) && |
| 212 | unlikely(tick_is_expired(chn->wex, now_ms))) |
| 213 | chn->flags |= CF_WRITE_TIMEOUT; |
Willy Tarreau | 2eb52f0 | 2008-09-04 09:14:08 +0200 | [diff] [blame] | 214 | |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 215 | if (likely(!(chn->flags & CF_ANA_TIMEOUT)) && |
| 216 | unlikely(tick_is_expired(chn->analyse_exp, now_ms))) |
| 217 | chn->flags |= CF_ANA_TIMEOUT; |
Willy Tarreau | 2eb52f0 | 2008-09-04 09:14:08 +0200 | [diff] [blame] | 218 | } |
| 219 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 220 | /* Erase any content from channel <buf> and adjusts flags accordingly. Note |
Willy Tarreau | 0abebcc | 2009-01-08 00:09:41 +0100 | [diff] [blame] | 221 | * that any spliced data is not affected since we may not have any access to |
| 222 | * it. |
Willy Tarreau | e393fe2 | 2008-08-16 22:18:07 +0200 | [diff] [blame] | 223 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 224 | static inline void channel_erase(struct channel *chn) |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 225 | { |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 226 | chn->buf->o = 0; |
| 227 | chn->buf->i = 0; |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 228 | chn->to_forward = 0; |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 229 | chn->buf->p = chn->buf->data; |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 230 | } |
| 231 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 232 | /* marks the channel as "shutdown" ASAP for reads */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 233 | static inline void channel_shutr_now(struct channel *chn) |
Willy Tarreau | fa7e102 | 2008-10-19 07:30:41 +0200 | [diff] [blame] | 234 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 235 | chn->flags |= CF_SHUTR_NOW; |
Willy Tarreau | fa7e102 | 2008-10-19 07:30:41 +0200 | [diff] [blame] | 236 | } |
| 237 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 238 | /* marks the channel as "shutdown" ASAP for writes */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 239 | static inline void channel_shutw_now(struct channel *chn) |
Willy Tarreau | fa7e102 | 2008-10-19 07:30:41 +0200 | [diff] [blame] | 240 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 241 | chn->flags |= CF_SHUTW_NOW; |
Willy Tarreau | fa7e102 | 2008-10-19 07:30:41 +0200 | [diff] [blame] | 242 | } |
| 243 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 244 | /* marks the channel as "shutdown" ASAP in both directions */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 245 | static inline void channel_abort(struct channel *chn) |
Willy Tarreau | fa7e102 | 2008-10-19 07:30:41 +0200 | [diff] [blame] | 246 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 247 | chn->flags |= CF_SHUTR_NOW | CF_SHUTW_NOW; |
| 248 | chn->flags &= ~CF_AUTO_CONNECT; |
Willy Tarreau | fa7e102 | 2008-10-19 07:30:41 +0200 | [diff] [blame] | 249 | } |
| 250 | |
Willy Tarreau | 520d95e | 2009-09-19 21:04:57 +0200 | [diff] [blame] | 251 | /* allow the consumer to try to establish a new connection. */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 252 | static inline void channel_auto_connect(struct channel *chn) |
Willy Tarreau | 3da77c5 | 2008-08-29 09:58:42 +0200 | [diff] [blame] | 253 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 254 | chn->flags |= CF_AUTO_CONNECT; |
Willy Tarreau | 3da77c5 | 2008-08-29 09:58:42 +0200 | [diff] [blame] | 255 | } |
| 256 | |
Willy Tarreau | 520d95e | 2009-09-19 21:04:57 +0200 | [diff] [blame] | 257 | /* prevent the consumer from trying to establish a new connection, and also |
| 258 | * disable auto shutdown forwarding. |
| 259 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 260 | static inline void channel_dont_connect(struct channel *chn) |
Willy Tarreau | 3da77c5 | 2008-08-29 09:58:42 +0200 | [diff] [blame] | 261 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 262 | chn->flags &= ~(CF_AUTO_CONNECT|CF_AUTO_CLOSE); |
Willy Tarreau | 3da77c5 | 2008-08-29 09:58:42 +0200 | [diff] [blame] | 263 | } |
| 264 | |
Willy Tarreau | 520d95e | 2009-09-19 21:04:57 +0200 | [diff] [blame] | 265 | /* allow the producer to forward shutdown requests */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 266 | static inline void channel_auto_close(struct channel *chn) |
Willy Tarreau | 0a5d5dd | 2008-11-23 19:31:35 +0100 | [diff] [blame] | 267 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 268 | chn->flags |= CF_AUTO_CLOSE; |
Willy Tarreau | 0a5d5dd | 2008-11-23 19:31:35 +0100 | [diff] [blame] | 269 | } |
| 270 | |
Willy Tarreau | 520d95e | 2009-09-19 21:04:57 +0200 | [diff] [blame] | 271 | /* prevent the producer from forwarding shutdown requests */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 272 | static inline void channel_dont_close(struct channel *chn) |
Willy Tarreau | 0a5d5dd | 2008-11-23 19:31:35 +0100 | [diff] [blame] | 273 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 274 | chn->flags &= ~CF_AUTO_CLOSE; |
Willy Tarreau | 0a5d5dd | 2008-11-23 19:31:35 +0100 | [diff] [blame] | 275 | } |
| 276 | |
Willy Tarreau | 90deb18 | 2010-01-07 00:20:41 +0100 | [diff] [blame] | 277 | /* allow the producer to read / poll the input */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 278 | static inline void channel_auto_read(struct channel *chn) |
Willy Tarreau | 90deb18 | 2010-01-07 00:20:41 +0100 | [diff] [blame] | 279 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 280 | chn->flags &= ~CF_DONT_READ; |
Willy Tarreau | 90deb18 | 2010-01-07 00:20:41 +0100 | [diff] [blame] | 281 | } |
| 282 | |
| 283 | /* prevent the producer from read / poll the input */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 284 | static inline void channel_dont_read(struct channel *chn) |
Willy Tarreau | 90deb18 | 2010-01-07 00:20:41 +0100 | [diff] [blame] | 285 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 286 | chn->flags |= CF_DONT_READ; |
Willy Tarreau | 90deb18 | 2010-01-07 00:20:41 +0100 | [diff] [blame] | 287 | } |
| 288 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 289 | |
| 290 | /*************************************************/ |
| 291 | /* Buffer operations in the context of a channel */ |
| 292 | /*************************************************/ |
| 293 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 294 | |
| 295 | /* Return the max number of bytes the buffer can contain so that once all the |
| 296 | * pending bytes are forwarded, the buffer still has global.tune.maxrewrite |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 297 | * bytes free. The result sits between chn->size - maxrewrite and chn->size. |
Willy Tarreau | 467c147 | 2016-04-20 18:05:17 +0200 | [diff] [blame] | 298 | * It is important to mention that if buf->i is already larger than size-maxrw |
| 299 | * the condition above cannot be satisfied and the lowest size will be returned |
| 300 | * anyway. The principles are the following : |
| 301 | * 1) a non-connected buffer cannot touch the reserve |
| 302 | * 2) infinite forward can always fill the buffer since all data will leave |
| 303 | * 3) all output bytes are considered in transit since they're leaving |
| 304 | * 4) all input bytes covered by to_forward are considered in transit since |
| 305 | * they'll be converted to output bytes. |
| 306 | * 5) all input bytes not covered by to_forward as considered remaining |
| 307 | * 6) all bytes scheduled to be forwarded minus what is already in the input |
| 308 | * buffer will be in transit during future rounds. |
| 309 | * 7) 4+5+6 imply that the amount of input bytes (i) is irrelevant to the max |
| 310 | * usable length, only to_forward and output count. The difference is |
| 311 | * visible when to_forward > i. |
| 312 | * 8) the reserve may be covered up to the amount of bytes in transit since |
| 313 | * these bytes will only take temporary space. |
Willy Tarreau | 7610073 | 2016-01-25 01:09:11 +0100 | [diff] [blame] | 314 | * |
Willy Tarreau | 467c147 | 2016-04-20 18:05:17 +0200 | [diff] [blame] | 315 | * A typical buffer looks like this : |
Willy Tarreau | 7610073 | 2016-01-25 01:09:11 +0100 | [diff] [blame] | 316 | * |
Willy Tarreau | 467c147 | 2016-04-20 18:05:17 +0200 | [diff] [blame] | 317 | * <-------------- max_len -----------> |
| 318 | * <---- o ----><----- i -----> <--- 0..maxrewrite ---> |
| 319 | * +------------+--------------+-------+----------------------+ |
| 320 | * |////////////|\\\\\\\\\\\\\\|xxxxxxx| reserve | |
| 321 | * +------------+--------+-----+-------+----------------------+ |
| 322 | * <- fwd -> <-avail-> |
| 323 | * |
| 324 | * Or when to_forward > i : |
| 325 | * |
| 326 | * <-------------- max_len -----------> |
| 327 | * <---- o ----><----- i -----> <--- 0..maxrewrite ---> |
| 328 | * +------------+--------------+-------+----------------------+ |
| 329 | * |////////////|\\\\\\\\\\\\\\|xxxxxxx| reserve | |
| 330 | * +------------+--------+-----+-------+----------------------+ |
| 331 | * <-avail-> |
| 332 | * <------------------ fwd ----------------> |
| 333 | * |
| 334 | * - the amount of buffer bytes in transit is : min(i, fwd) + o |
| 335 | * - some scheduled bytes may be in transit (up to fwd - i) |
| 336 | * - the reserve is max(0, maxrewrite - transit) |
| 337 | * - the maximum usable buffer length is size - reserve. |
| 338 | * - the available space is max_len - i - o |
| 339 | * |
| 340 | * So the formula to compute the buffer's maximum length to protect the reserve |
| 341 | * when reading new data is : |
| 342 | * |
| 343 | * max = size - maxrewrite + min(maxrewrite, transit) |
| 344 | * = size - max(maxrewrite - transit, 0) |
| 345 | * |
| 346 | * But WARNING! The conditions might change during the transfer and it could |
| 347 | * very well happen that a buffer would contain more bytes than max_len due to |
| 348 | * i+o already walking over the reserve (eg: after a header rewrite), including |
| 349 | * i or o alone hitting the limit. So it is critical to always consider that |
| 350 | * bounds may have already been crossed and that available space may be negative |
| 351 | * for example. Due to this it is perfectly possible for this function to return |
| 352 | * a value that is lower than current i+o. |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 353 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 354 | static inline int buffer_max_len(const struct channel *chn) |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 355 | { |
Willy Tarreau | 2f3eda7 | 2016-05-03 17:46:24 +0200 | [diff] [blame] | 356 | unsigned int transit; |
Willy Tarreau | 7610073 | 2016-01-25 01:09:11 +0100 | [diff] [blame] | 357 | int reserve; |
| 358 | |
| 359 | /* return size - maxrewrite if we can't send */ |
| 360 | reserve = global.tune.maxrewrite; |
| 361 | if (unlikely(!channel_may_send(chn))) |
| 362 | goto end; |
| 363 | |
Willy Tarreau | 2f3eda7 | 2016-05-03 17:46:24 +0200 | [diff] [blame] | 364 | /* We need to check what remains of the reserve after o and to_forward |
| 365 | * have been transmitted, but they can overflow together and they can |
| 366 | * cause an integer underflow in the comparison since both are unsigned |
| 367 | * while maxrewrite is signed. |
| 368 | * The code below has been verified for being a valid check for this : |
| 369 | * - if (o + to_forward) overflow => return size [ large enough ] |
| 370 | * - if o + to_forward >= maxrw => return size [ large enough ] |
| 371 | * - otherwise return size - (maxrw - (o + to_forward)) |
Willy Tarreau | 7610073 | 2016-01-25 01:09:11 +0100 | [diff] [blame] | 372 | */ |
Willy Tarreau | 2f3eda7 | 2016-05-03 17:46:24 +0200 | [diff] [blame] | 373 | transit = chn->buf->o + chn->to_forward; |
| 374 | reserve -= transit; |
| 375 | if (transit < chn->to_forward || // addition overflow |
| 376 | transit >= (unsigned)global.tune.maxrewrite) // enough transit data |
Willy Tarreau | 467c147 | 2016-04-20 18:05:17 +0200 | [diff] [blame] | 377 | return chn->buf->size; |
Willy Tarreau | 7610073 | 2016-01-25 01:09:11 +0100 | [diff] [blame] | 378 | end: |
| 379 | return chn->buf->size - reserve; |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 380 | } |
| 381 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 382 | /* Returns the amount of space available at the input of the buffer, taking the |
| 383 | * reserved space into account if ->to_forward indicates that an end of transfer |
| 384 | * is close to happen. The test is optimized to avoid as many operations as |
| 385 | * possible for the fast case. |
| 386 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 387 | static inline int bi_avail(const struct channel *chn) |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 388 | { |
Willy Tarreau | 18b09d0 | 2015-01-14 15:56:50 +0100 | [diff] [blame] | 389 | int ret; |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 390 | |
Willy Tarreau | 18b09d0 | 2015-01-14 15:56:50 +0100 | [diff] [blame] | 391 | ret = buffer_max_len(chn) - chn->buf->i - chn->buf->o; |
| 392 | if (ret < 0) |
| 393 | ret = 0; |
| 394 | return ret; |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 395 | } |
| 396 | |
| 397 | /* Cut the "tail" of the channel's buffer, which means strip it to the length |
| 398 | * of unsent data only, and kill any remaining unsent data. Any scheduled |
| 399 | * forwarding is stopped. This is mainly to be used to send error messages |
| 400 | * after existing data. |
| 401 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 402 | static inline void bi_erase(struct channel *chn) |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 403 | { |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 404 | if (!chn->buf->o) |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 405 | return channel_erase(chn); |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 406 | |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 407 | chn->to_forward = 0; |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 408 | if (!chn->buf->i) |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 409 | return; |
| 410 | |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 411 | chn->buf->i = 0; |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 412 | } |
| 413 | |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 414 | /* |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 415 | * Advance the channel buffer's read pointer by <len> bytes. This is useful |
| 416 | * when data have been read directly from the buffer. It is illegal to call |
| 417 | * this function with <len> causing a wrapping at the end of the buffer. It's |
| 418 | * the caller's responsibility to ensure that <len> is never larger than |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 419 | * chn->o. Channel flag WRITE_PARTIAL is set. |
Willy Tarreau | 2b7addc | 2009-08-31 07:37:22 +0200 | [diff] [blame] | 420 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 421 | static inline void bo_skip(struct channel *chn, int len) |
Willy Tarreau | 2b7addc | 2009-08-31 07:37:22 +0200 | [diff] [blame] | 422 | { |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 423 | chn->buf->o -= len; |
Willy Tarreau | 9dab5fc | 2012-05-07 11:56:55 +0200 | [diff] [blame] | 424 | |
Willy Tarreau | 5fb3803 | 2012-12-16 19:39:09 +0100 | [diff] [blame] | 425 | if (buffer_empty(chn->buf)) |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 426 | chn->buf->p = chn->buf->data; |
Willy Tarreau | 2b7addc | 2009-08-31 07:37:22 +0200 | [diff] [blame] | 427 | |
Willy Tarreau | fb0e920 | 2009-09-23 23:47:55 +0200 | [diff] [blame] | 428 | /* notify that some data was written to the SI from the buffer */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 429 | chn->flags |= CF_WRITE_PARTIAL; |
Willy Tarreau | 2b7addc | 2009-08-31 07:37:22 +0200 | [diff] [blame] | 430 | } |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 431 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 432 | /* Tries to copy chunk <chunk> into the channel's buffer after length controls. |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 433 | * The chn->o and to_forward pointers are updated. If the channel's input is |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 434 | * closed, -2 is returned. If the block is too large for this buffer, -3 is |
| 435 | * returned. If there is not enough room left in the buffer, -1 is returned. |
| 436 | * Otherwise the number of bytes copied is returned (0 being a valid number). |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 437 | * Channel flag READ_PARTIAL is updated if some data can be transferred. The |
Willy Tarreau | f941cf2 | 2012-08-27 20:53:34 +0200 | [diff] [blame] | 438 | * chunk's length is updated with the number of bytes sent. |
Willy Tarreau | aeac319 | 2009-08-31 08:09:57 +0200 | [diff] [blame] | 439 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 440 | static inline int bi_putchk(struct channel *chn, struct chunk *chunk) |
Willy Tarreau | aeac319 | 2009-08-31 08:09:57 +0200 | [diff] [blame] | 441 | { |
| 442 | int ret; |
| 443 | |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 444 | ret = bi_putblk(chn, chunk->str, chunk->len); |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 445 | if (ret > 0) |
| 446 | chunk->len -= ret; |
Willy Tarreau | aeac319 | 2009-08-31 08:09:57 +0200 | [diff] [blame] | 447 | return ret; |
| 448 | } |
| 449 | |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 450 | /* Tries to copy string <str> at once into the channel's buffer after length |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 451 | * controls. The chn->o and to_forward pointers are updated. If the channel's |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 452 | * input is closed, -2 is returned. If the block is too large for this buffer, |
| 453 | * -3 is returned. If there is not enough room left in the buffer, -1 is |
| 454 | * returned. Otherwise the number of bytes copied is returned (0 being a valid |
| 455 | * number). Channel flag READ_PARTIAL is updated if some data can be |
| 456 | * transferred. |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 457 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 458 | static inline int bi_putstr(struct channel *chn, const char *str) |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 459 | { |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 460 | return bi_putblk(chn, str, strlen(str)); |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 461 | } |
| 462 | |
| 463 | /* |
Willy Tarreau | 8263d2b | 2012-08-28 00:06:31 +0200 | [diff] [blame] | 464 | * Return one char from the channel's buffer. If the buffer is empty and the |
| 465 | * channel is closed, return -2. If the buffer is just empty, return -1. The |
| 466 | * buffer's pointer is not advanced, it's up to the caller to call bo_skip(buf, |
| 467 | * 1) when it has consumed the char. Also note that this function respects the |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 468 | * chn->o limit. |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 469 | */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 470 | static inline int bo_getchr(struct channel *chn) |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 471 | { |
| 472 | /* closed or empty + imminent close = -2; empty = -1 */ |
Willy Tarreau | 974ced6 | 2012-10-12 23:11:02 +0200 | [diff] [blame] | 473 | if (unlikely((chn->flags & CF_SHUTW) || channel_is_empty(chn))) { |
| 474 | if (chn->flags & (CF_SHUTW|CF_SHUTW_NOW)) |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 475 | return -2; |
| 476 | return -1; |
| 477 | } |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 478 | return *buffer_wrap_sub(chn->buf, chn->buf->p - chn->buf->o); |
Willy Tarreau | 74b08c9 | 2010-09-08 17:04:31 +0200 | [diff] [blame] | 479 | } |
| 480 | |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 481 | |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 482 | #endif /* _PROTO_CHANNEL_H */ |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 483 | |
| 484 | /* |
| 485 | * Local variables: |
| 486 | * c-indent-level: 8 |
| 487 | * c-basic-offset: 8 |
| 488 | * End: |
| 489 | */ |