1 /* 2 * Copyright 2013 Marek Olk <maraeo (at) gmail.com> 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * on the rights to use, copy, modify, merge, publish, distribute, sub 8 * license, and/or sell copies of the Software, and to permit persons to whom 9 * the Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, 19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 21 * USE OR OTHER DEALINGS IN THE SOFTWARE. */ 22 23 /** 24 * @file 25 * 1D integer range, capable of the union and intersection operations. 26 * 27 * It only maintains a single interval which is extended when the union is 28 * done. This implementation is partially thread-safe (readers are not 29 * protected by a lock). 30 * 31 * @author Marek Olk 32 */ 33 34 #ifndef U_RANGE_H 35 #define U_RANGE_H 36 37 #include "os/os_thread.h" 38 39 #include "util/u_math.h" 40 41 struct util_range { 42 unsigned start; /* inclusive */ 43 unsigned end; /* exclusive */ 44 45 /* for the range to be consistent with multiple contexts: */ 46 pipe_mutex write_mutex; 47 }; 48 49 50 static inline void 51 util_range_set_empty(struct util_range *range) 52 { 53 range->start = ~0; 54 range->end = 0; 55 } 56 57 /* This is like a union of two sets. */ 58 static inline void 59 util_range_add(struct util_range *range, unsigned start, unsigned end) 60 { 61 if (start < range->start || end > range->end) { 62 pipe_mutex_lock(range->write_mutex); 63 range->start = MIN2(start, range->start); 64 range->end = MAX2(end, range->end); 65 pipe_mutex_unlock(range->write_mutex); 66 } 67 } 68 69 static inline boolean 70 util_ranges_intersect(struct util_range *range, unsigned start, unsigned end) 71 { 72 return MAX2(start, range->start) < MIN2(end, range->end); 73 } 74 75 76 /* Init/deinit */ 77 78 static inline void 79 util_range_init(struct util_range *range) 80 { 81 pipe_mutex_init(range->write_mutex); 82 util_range_set_empty(range); 83 } 84 85 static inline void 86 util_range_destroy(struct util_range *range) 87 { 88 pipe_mutex_destroy(range->write_mutex); 89 } 90 91 #endif 92
