From 95fa22a65cf0866afaf3efd933a180509922f047 Mon Sep 17 00:00:00 2001 From: Lukas Joeressen Date: Mon, 15 Jun 2015 15:03:44 +0200 Subject: Rounding errors could make time_alloc imprecise --- mrbgems/mruby-time/src/time.c | 5 +++-- mrbgems/mruby-time/test/time.rb | 8 ++++++++ 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/mrbgems/mruby-time/src/time.c b/mrbgems/mruby-time/src/time.c index b377f3e33..36bbbe00a 100644 --- a/mrbgems/mruby-time/src/time.c +++ b/mrbgems/mruby-time/src/time.c @@ -6,6 +6,7 @@ #include #include +#include #include "mruby.h" #include "mruby/class.h" #include "mruby/data.h" @@ -208,12 +209,12 @@ time_alloc(mrb_state *mrb, double sec, double usec, enum mrb_timezone timezone) out_of_range: mrb_raisef(mrb, E_ARGUMENT_ERROR, "%S out of Time range", mrb_float_value(mrb, sec)); } - tm->usec = (time_t)((sec - tm->sec) * 1.0e6 + usec); + tm->usec = (time_t)llrint((sec - tm->sec) * 1.0e6 + usec); while (tm->usec < 0) { tm->sec--; tm->usec += 1000000; } - while (tm->usec > 1000000) { + while (tm->usec >= 1000000) { tm->sec++; tm->usec -= 1000000; } diff --git a/mrbgems/mruby-time/test/time.rb b/mrbgems/mruby-time/test/time.rb index ba9b48fab..759e2881d 100644 --- a/mrbgems/mruby-time/test/time.rb +++ b/mrbgems/mruby-time/test/time.rb @@ -203,3 +203,11 @@ assert('day of week methods') do assert_false t.friday? assert_false t.saturday? end + +assert('2000 times 500us make a second') do + t = Time.utc 2015 + 2000.times do + t += 0.0005 + end + t.usec == 0 +end -- cgit v1.2.3