From d8d863314c4753067c50667a9bb2aa42791fe272 Mon Sep 17 00:00:00 2001 From: wang-bin Date: Tue, 3 Jan 2017 13:57:35 +0800 Subject: [PATCH] check clock_gettime at runtime for apple platforms clock_gettime is avalible since macOS 10.12 and iOS 10.0. Because of weak linking, clock_gettime can be build without error with new macOS/iOS sdk, but the symbol may not exist on the target system. Explicitly checking the symbol is required. https://developer.apple.com/library/content/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/WeakLinking.html --- libavutil/time.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/libavutil/time.c b/libavutil/time.c index dbaee0264c..afa6658aa6 100644 --- a/libavutil/time.c +++ b/libavutil/time.c @@ -56,17 +56,25 @@ int64_t av_gettime(void) int64_t av_gettime_relative(void) { #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC) - struct timespec ts; - clock_gettime(CLOCK_MONOTONIC, &ts); - return (int64_t)ts.tv_sec * 1000000 + ts.tv_nsec / 1000; -#else - return av_gettime() + 42 * 60 * 60 * INT64_C(1000000); +#ifdef __APPLE__ + if (clock_gettime) +#endif + { + struct timespec ts; + clock_gettime(CLOCK_MONOTONIC, &ts); + return (int64_t)ts.tv_sec * 1000000 + ts.tv_nsec / 1000; + } #endif + return av_gettime() + 42 * 60 * 60 * INT64_C(1000000); } int av_gettime_relative_is_monotonic(void) { #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC) +#ifdef __APPLE__ + if (!clock_gettime) + return 0; +#endif return 1; #else return 0; -- 2.11.0