1 /* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 18 /** 19 ************************************************************************ 20 * @file M4OSA_Clock.c 21 * @brief Clock related functions 22 * @note This file implements functions to manipulate clock 23 ************************************************************************ 24 */ 25 26 #include <sys/time.h> 27 #include <time.h> 28 29 #include "M4OSA_Debug.h" 30 #include "M4OSA_Clock.h" 31 #include "M4OSA_Memory.h" 32 #include "M4OSA_Types.h" 33 34 35 36 37 /** 38 ************************************************************************ 39 * @brief This function gets an absolute time to an unknown reference with 40 * a high precision. 41 * @note It means it can only be used to get a relative time by computing 42 * differences between to times. 43 * It is to the caller to allocate time. Time is expressed in 44 * timescale unit. 45 * M4OSA_ROLLOVER_CLOCK in M4OSA_Types.h must be configured with the rollover 46 * offset of this function. 47 * @param time: (IN/OUT) time 48 * @param timescale: (IN) The timescale (time unit per second) 49 * @return M4NO_ERROR: there is no error 50 * @return M4ERR_PARAMETER: at least one parameter is NULL 51 * @return M4WAR_TIMESCALE_TOO_BIG: the precision of the system clock is 52 * not 53 * compliant with the input timescale 54 ************************************************************************ 55 */ 56 M4OSA_ERR M4OSA_clockGetTime(M4OSA_Time* pTime, M4OSA_UInt32 timescale) 57 { 58 struct timeval tv; 59 struct timezone tz; 60 M4OSA_UInt32 u32_time = 0; 61 M4OSA_UInt32 u32_time_hi; 62 M4OSA_UInt32 u32_time_lo; 63 M4OSA_UInt32 u32_time_lh; 64 M4OSA_UInt32 factor; 65 66 M4OSA_TRACE1_2("M4OSA_clockGetTime\t\tM4OSA_Time* 0x%x\tM4OSA_UInt32 %d", 67 pTime, timescale); 68 69 M4OSA_DEBUG_IF2(M4OSA_NULL == pTime, M4ERR_PARAMETER, 70 "M4OSA_clockGetTime: pTime is M4OSA_NULL"); 71 M4OSA_DEBUG_IF2(0 == timescale, M4ERR_PARAMETER, 72 "M4OSA_clockGetTime: timescale is 0"); 73 74 factor = 1000000 / timescale; 75 76 if(gettimeofday(&tv, &tz) == 0) 77 { 78 u32_time_lo = (tv.tv_sec & 0xFFFF) * timescale; 79 u32_time_hi = (((tv.tv_sec >> 16) & 0xFFFF) * timescale) + ((u32_time_lo >> 16) & 0xFFFF); 80 u32_time_lo &= 0xFFFF; 81 u32_time_lo += tv.tv_usec / factor; 82 u32_time_hi += ((u32_time_lo >> 16) & 0xFFFF); 83 u32_time_lo &= 0xFFFF; 84 u32_time = ((u32_time_hi & 0x7FFF) << 16) | u32_time_lo; 85 } 86 87 /* M4OSA_Time is signed, so we need to check the max value*/ 88 if (u32_time > M4OSA_INT32_MAX) 89 { 90 u32_time = u32_time - M4OSA_INT32_MAX; 91 } 92 93 *pTime = (M4OSA_Time)u32_time; 94 95 if( timescale > 10000 ) 96 { 97 return M4WAR_TIMESCALE_TOO_BIG; 98 } 99 100 return M4NO_ERROR; 101 } 102
