| /* quirc -- QR-code recognition library |
| * Copyright (C) 2010-2012 Daniel Beer <dlbeer@gmail.com> |
| * |
| * Permission to use, copy, modify, and/or distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| */ |
| |
| #ifndef DTHASH_H_ |
| #define DTHASH_H_ |
| |
| #include <stdint.h> |
| #include <time.h> |
| #include "quirc.h" |
| |
| /* Detector hash. |
| * |
| * This structure keeps track of codes that have been seen within the |
| * last N seconds, and allows us to print out codes at a reasonable |
| * rate as we see them. |
| */ |
| #define DTHASH_MAX_CODES 32 |
| |
| struct dthash_code { |
| uint32_t hash; |
| time_t when; |
| }; |
| |
| struct dthash { |
| struct dthash_code codes[DTHASH_MAX_CODES]; |
| int count; |
| int timeout; |
| }; |
| |
| /* Initialise a detector hash with the given timeout. */ |
| void dthash_init(struct dthash *d, int timeout); |
| |
| /* When a code is discovered, this function should be called to see if |
| * it should be printed. The hash will record having seen the code, and |
| * return non-zero if it's the first time we've seen it within the |
| * configured timeout period. |
| */ |
| int dthash_seen(struct dthash *d, const struct quirc_data *data); |
| |
| #endif |
