stopwatch.h (1846B)
1 // Copyright 2011 Google Inc. All Rights Reserved. 2 // 3 // Use of this source code is governed by a BSD-style license 4 // that can be found in the COPYING file in the root of the source 5 // tree. An additional intellectual property rights grant can be found 6 // in the file PATENTS. All contributing project authors may 7 // be found in the AUTHORS file in the root of the source tree. 8 // ----------------------------------------------------------------------------- 9 // 10 // Helper functions to measure elapsed time. 11 // 12 // Author: Mikolaj Zalewski (mikolajz@google.com) 13 14 #ifndef WEBP_EXAMPLES_STOPWATCH_H_ 15 #define WEBP_EXAMPLES_STOPWATCH_H_ 16 17 #include "webp/types.h" 18 19 #if defined _WIN32 && !defined __GNUC__ 20 #include <windows.h> 21 22 typedef LARGE_INTEGER Stopwatch; 23 24 static WEBP_INLINE void StopwatchReset(Stopwatch* watch) { 25 QueryPerformanceCounter(watch); 26 } 27 28 static WEBP_INLINE double StopwatchReadAndReset(Stopwatch* watch) { 29 const LARGE_INTEGER old_value = *watch; 30 LARGE_INTEGER freq; 31 if (!QueryPerformanceCounter(watch)) 32 return 0.0; 33 if (!QueryPerformanceFrequency(&freq)) 34 return 0.0; 35 if (freq.QuadPart == 0) 36 return 0.0; 37 return (watch->QuadPart - old_value.QuadPart) / (double)freq.QuadPart; 38 } 39 40 41 #else /* !_WIN32 */ 42 #include <string.h> // memcpy 43 #include <sys/time.h> 44 45 typedef struct timeval Stopwatch; 46 47 static WEBP_INLINE void StopwatchReset(Stopwatch* watch) { 48 gettimeofday(watch, NULL); 49 } 50 51 static WEBP_INLINE double StopwatchReadAndReset(Stopwatch* watch) { 52 struct timeval old_value; 53 double delta_sec, delta_usec; 54 memcpy(&old_value, watch, sizeof(old_value)); 55 gettimeofday(watch, NULL); 56 delta_sec = (double)watch->tv_sec - old_value.tv_sec; 57 delta_usec = (double)watch->tv_usec - old_value.tv_usec; 58 return delta_sec + delta_usec / 1000000.0; 59 } 60 61 #endif /* _WIN32 */ 62 63 #endif // WEBP_EXAMPLES_STOPWATCH_H_