generic-library/bionic
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

am 4ef0e59f: Merge "Reimplement clock(3) using clock_gettime(3)"

Browse Source 
* commit '4ef0e59f339ad138eabe3bc408beda6004f5ea83':
  Reimplement clock(3) using clock_gettime(3)
This commit is contained in:
Elliott Hughes
2014-10-04 02:17:19 +00:00
committed by Android Git Automerger
parent bf956e863e 4ef0e59f33
commit 5f86872e67
2 changed files with 15 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
libc/bionic/clock.cpp
View File

@@ -30,12 +30,13 @@
#include <sys/sysconf.h>
#include <sys/times.h>
#include "private/bionic_constants.h"
// http://pubs.opengroup.org/onlinepubs/9699919799/functions/clock.html
clock_t clock() {
tms t;
times(&t);
// Although times(2) and clock(3) both use the type clock_t, the units are
// different. For times(2) it's pure clock ticks, but for clock(3) the unit
// is CLOCKS_PER_SEC, so we need to scale appropriately.
return (t.tms_utime + t.tms_stime) * (CLOCKS_PER_SEC / sysconf(_SC_CLK_TCK));
timespec ts;
if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts) == -1) {
return -1;
}
return (ts.tv_sec * CLOCKS_PER_SEC) + (ts.tv_nsec / (NS_PER_S / CLOCKS_PER_SEC));
}