1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/ipc/chromium/src/third_party/libevent/ratelim-internal.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,105 @@
1.4 +/*
1.5 + * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson
1.6 + *
1.7 + * Redistribution and use in source and binary forms, with or without
1.8 + * modification, are permitted provided that the following conditions
1.9 + * are met:
1.10 + * 1. Redistributions of source code must retain the above copyright
1.11 + * notice, this list of conditions and the following disclaimer.
1.12 + * 2. Redistributions in binary form must reproduce the above copyright
1.13 + * notice, this list of conditions and the following disclaimer in the
1.14 + * documentation and/or other materials provided with the distribution.
1.15 + * 3. The name of the author may not be used to endorse or promote products
1.16 + * derived from this software without specific prior written permission.
1.17 + *
1.18 + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
1.19 + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
1.20 + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
1.21 + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
1.22 + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
1.23 + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1.24 + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1.25 + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.26 + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
1.27 + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.28 + */
1.29 +#ifndef _RATELIM_INTERNAL_H_
1.30 +#define _RATELIM_INTERNAL_H_
1.31 +
1.32 +#ifdef __cplusplus
1.33 +extern "C" {
1.34 +#endif
1.35 +
1.36 +#include "event2/util.h"
1.37 +
1.38 +/** A token bucket is an internal structure that tracks how many bytes we are
1.39 + * currently willing to read or write on a given bufferevent or group of
1.40 + * bufferevents */
1.41 +struct ev_token_bucket {
1.42 + /** How many bytes are we willing to read or write right now? These
1.43 + * values are signed so that we can do "defecit spending" */
1.44 + ev_ssize_t read_limit, write_limit;
1.45 + /** When was this bucket last updated? Measured in abstract 'ticks'
1.46 + * relative to the token bucket configuration. */
1.47 + ev_uint32_t last_updated;
1.48 +};
1.49 +
1.50 +/** Configuration info for a token bucket or set of token buckets. */
1.51 +struct ev_token_bucket_cfg {
1.52 + /** How many bytes are we willing to read on average per tick? */
1.53 + size_t read_rate;
1.54 + /** How many bytes are we willing to read at most in any one tick? */
1.55 + size_t read_maximum;
1.56 + /** How many bytes are we willing to write on average per tick? */
1.57 + size_t write_rate;
1.58 + /** How many bytes are we willing to write at most in any one tick? */
1.59 + size_t write_maximum;
1.60 +
1.61 + /* How long is a tick? Note that fractions of a millisecond are
1.62 + * ignored. */
1.63 + struct timeval tick_timeout;
1.64 +
1.65 + /* How long is a tick, in milliseconds? Derived from tick_timeout. */
1.66 + unsigned msec_per_tick;
1.67 +};
1.68 +
1.69 +/** The current tick is 'current_tick': add bytes to 'bucket' as specified in
1.70 + * 'cfg'. */
1.71 +int ev_token_bucket_update(struct ev_token_bucket *bucket,
1.72 + const struct ev_token_bucket_cfg *cfg,
1.73 + ev_uint32_t current_tick);
1.74 +
1.75 +/** In which tick does 'tv' fall according to 'cfg'? Note that ticks can
1.76 + * overflow easily; your code needs to handle this. */
1.77 +ev_uint32_t ev_token_bucket_get_tick(const struct timeval *tv,
1.78 + const struct ev_token_bucket_cfg *cfg);
1.79 +
1.80 +/** Adjust 'bucket' to respect 'cfg', and note that it was last updated in
1.81 + * 'current_tick'. If 'reinitialize' is true, we are changing the
1.82 + * configuration of 'bucket'; otherwise, we are setting it up for the first
1.83 + * time.
1.84 + */
1.85 +int ev_token_bucket_init(struct ev_token_bucket *bucket,
1.86 + const struct ev_token_bucket_cfg *cfg,
1.87 + ev_uint32_t current_tick,
1.88 + int reinitialize);
1.89 +
1.90 +int bufferevent_remove_from_rate_limit_group_internal(struct bufferevent *bev,
1.91 + int unsuspend);
1.92 +
1.93 +/** Decrease the read limit of 'b' by 'n' bytes */
1.94 +#define ev_token_bucket_decrement_read(b,n) \
1.95 + do { \
1.96 + (b)->read_limit -= (n); \
1.97 + } while (0)
1.98 +/** Decrease the write limit of 'b' by 'n' bytes */
1.99 +#define ev_token_bucket_decrement_write(b,n) \
1.100 + do { \
1.101 + (b)->write_limit -= (n); \
1.102 + } while (0)
1.103 +
1.104 +#ifdef __cplusplus
1.105 +}
1.106 +#endif
1.107 +
1.108 +#endif
