1 /* 2 * Copyright (c) 2008-2011 Apple Inc. All rights reserved. 3 * 4 * @APPLE_APACHE_LICENSE_HEADER_START@ 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 * 18 * @APPLE_APACHE_LICENSE_HEADER_END@ 19 */ 20 21 #ifndef __DISPATCH_TIME__ 22 #define __DISPATCH_TIME__ 23 24 #ifndef __DISPATCH_INDIRECT__ 25 #error "Please #include <dispatch/dispatch.h> instead of this file directly." 26 #include <dispatch/base.h> // for HeaderDoc 27 #endif 28 29 #include <stdint.h> 30 31 // <rdar://problem/6368156&7563559> 32 #if TARGET_OS_MAC 33 #include <mach/clock_types.h> 34 #endif 35 36 #ifdef NSEC_PER_SEC 37 #undef NSEC_PER_SEC 38 #endif 39 #ifdef USEC_PER_SEC 40 #undef USEC_PER_SEC 41 #endif 42 #ifdef NSEC_PER_USEC 43 #undef NSEC_PER_USEC 44 #endif 45 #ifdef NSEC_PER_MSEC 46 #undef NSEC_PER_MSEC 47 #endif 48 #define NSEC_PER_SEC 1000000000ull 49 #define NSEC_PER_MSEC 1000000ull 50 #define USEC_PER_SEC 1000000ull 51 #define NSEC_PER_USEC 1000ull 52 53 __BEGIN_DECLS 54 55 struct timespec; 56 57 /*! 58 * @typedef dispatch_time_t 59 * 60 * @abstract 61 * A somewhat abstract representation of time; where zero means "now" and 62 * DISPATCH_TIME_FOREVER means "infinity" and every value in between is an 63 * opaque encoding. 64 */ 65 typedef uint64_t dispatch_time_t; 66 67 #define DISPATCH_TIME_NOW (0ull) 68 #define DISPATCH_TIME_FOREVER (~0ull) 69 70 /*! 71 * @function dispatch_time 72 * 73 * @abstract 74 * Create dispatch_time_t relative to the default clock or modify an existing 75 * dispatch_time_t. 76 * 77 * @discussion 78 * On Mac OS X the default clock is based on mach_absolute_time(). 79 * 80 * @param when 81 * An optional dispatch_time_t to add nanoseconds to. If zero is passed, then 82 * dispatch_time() will use the result of mach_absolute_time(). 83 * 84 * @param delta 85 * Nanoseconds to add. 86 * 87 * @result 88 * A new dispatch_time_t. 89 */ 90 __OSX_AVAILABLE_STARTING(__MAC_10_6,__IPHONE_4_0) 91 DISPATCH_EXPORT DISPATCH_WARN_RESULT DISPATCH_NOTHROW 92 dispatch_time_t 93 dispatch_time(dispatch_time_t when, int64_t delta); 94 95 /*! 96 * @function dispatch_walltime 97 * 98 * @abstract 99 * Create a dispatch_time_t using the wall clock. 100 * 101 * @discussion 102 * On Mac OS X the wall clock is based on gettimeofday(3). 103 * 104 * @param when 105 * A struct timespect to add time to. If NULL is passed, then 106 * dispatch_walltime() will use the result of gettimeofday(3). 107 * 108 * @param delta 109 * Nanoseconds to add. 110 * 111 * @result 112 * A new dispatch_time_t. 113 */ 114 __OSX_AVAILABLE_STARTING(__MAC_10_6,__IPHONE_4_0) 115 DISPATCH_EXPORT DISPATCH_WARN_RESULT DISPATCH_NOTHROW 116 dispatch_time_t 117 dispatch_walltime(const struct timespec *when, int64_t delta); 118 119 __END_DECLS 120 121 #endif 122