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/* |
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* Copyright (c) 2008-2009 Apple Inc. All rights reserved. |
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* |
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* @APPLE_APACHE_LICENSE_HEADER_START@ |
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* |
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* Licensed under the Apache License, Version 2.0 (the "License"); |
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* you may not use this file except in compliance with the License. |
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* You may obtain a copy of the License at |
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* |
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* http://www.apache.org/licenses/LICENSE-2.0 |
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* |
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* Unless required by applicable law or agreed to in writing, software |
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* distributed under the License is distributed on an "AS IS" BASIS, |
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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* See the License for the specific language governing permissions and |
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* limitations under the License. |
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* |
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* @APPLE_APACHE_LICENSE_HEADER_END@ |
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*/ |
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|
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/* |
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* IMPORTANT: This header file describes INTERNAL interfaces to libdispatch |
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* which are subject to change in future releases of Mac OS X. Any applications |
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* relying on these interfaces WILL break. |
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*/ |
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|
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#ifndef __DISPATCH_SHIMS_TIME__ |
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#define __DISPATCH_SHIMS_TIME__ |
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|
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#ifndef __DISPATCH_INDIRECT__ |
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#error "Please #include <dispatch/dispatch.h> instead of this file directly." |
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#endif |
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|
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uint64_t _dispatch_get_nanoseconds(void); |
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|
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#if TARGET_OS_WIN32 |
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static inline unsigned int |
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sleep(unsigned int seconds) |
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{ |
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Sleep(seconds * 1000); // milliseconds |
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return 0; |
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} |
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#endif |
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|
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#if (defined(__i386__) || defined(__x86_64__)) && HAVE_MACH_ABSOLUTE_TIME |
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// x86 currently implements mach time in nanoseconds; this is NOT likely to change |
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#define _dispatch_time_mach2nano(x) (x) |
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#define _dispatch_time_nano2mach(x) (x) |
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#else |
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typedef struct _dispatch_host_time_data_s { |
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long double frac; |
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bool ratio_1_to_1; |
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dispatch_once_t pred; |
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} _dispatch_host_time_data_s; |
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extern _dispatch_host_time_data_s _dispatch_host_time_data; |
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extern void _dispatch_get_host_time_init(void *context); |
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|
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static inline uint64_t |
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_dispatch_time_mach2nano(uint64_t machtime) |
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{ |
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_dispatch_host_time_data_s *const data = &_dispatch_host_time_data; |
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dispatch_once_f(&data->pred, NULL, _dispatch_get_host_time_init); |
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|
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return (uint64_t)(machtime * data->frac); |
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} |
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|
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static inline int64_t |
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_dispatch_time_nano2mach(int64_t nsec) |
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{ |
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_dispatch_host_time_data_s *const data = &_dispatch_host_time_data; |
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dispatch_once_f(&data->pred, NULL, _dispatch_get_host_time_init); |
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|
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if (slowpath(_dispatch_host_time_data.ratio_1_to_1)) { |
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return nsec; |
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} |
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|
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long double big_tmp = (long double)nsec; |
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|
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// Divide by tbi.numer/tbi.denom to convert nsec to Mach absolute time |
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big_tmp /= data->frac; |
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|
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// Clamp to a 64bit signed int |
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if (slowpath(big_tmp > INT64_MAX)) { |
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return INT64_MAX; |
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} |
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if (slowpath(big_tmp < INT64_MIN)) { |
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return INT64_MIN; |
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} |
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return (int64_t)big_tmp; |
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} |
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#endif |
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|
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static inline uint64_t |
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_dispatch_absolute_time(void) |
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{ |
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#if HAVE_MACH_ABSOLUTE_TIME |
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return mach_absolute_time(); |
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#elif TARGET_OS_WIN32 |
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LARGE_INTEGER now; |
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if (!QueryPerformanceCounter(&now)) { |
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return 0; |
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} |
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return now.QuadPart; |
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#else |
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struct timespec ts; |
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int ret; |
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|
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#if HAVE_DECL_CLOCK_UPTIME |
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ret = clock_gettime(CLOCK_UPTIME, &ts); |
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#elif HAVE_DECL_CLOCK_MONOTONIC |
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ret = clock_gettime(CLOCK_MONOTONIC, &ts); |
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#else |
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#error "clock_gettime: no supported absolute time clock" |
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#endif |
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(void)dispatch_assume_zero(ret); |
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|
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/* XXXRW: Some kind of overflow detection needed? */ |
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return (ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec); |
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#endif |
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} |
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|
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#endif /* __DISPATCH_SHIMS_TIME__ */ |
