| /* Copyright (C) 1994-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <stddef.h> |
| #include <errno.h> |
| #include <sys/time.h> |
| #include <hurd.h> |
| |
| /* XXX Temporary cheezoid implementation; see __setitmr.c. */ |
| |
| /* These are defined in __setitmr.c. */ |
| extern spin_lock_t _hurd_itimer_lock; |
| extern struct itimerval _hurd_itimerval; |
| extern struct timeval _hurd_itimer_started; |
| |
| static inline void |
| subtract_timeval (struct timeval *from, const struct timeval *subtract) |
| { |
| from->tv_usec -= subtract->tv_usec; |
| from->tv_sec -= subtract->tv_sec; |
| while (from->tv_usec < 0) |
| { |
| --from->tv_sec; |
| from->tv_usec += 1000000; |
| } |
| } |
| |
| /* Set *VALUE to the current setting of timer WHICH. |
| Return 0 on success, -1 on errors. */ |
| int |
| __getitimer (which, value) |
| enum __itimer_which which; |
| struct itimerval *value; |
| { |
| struct itimerval val; |
| struct timeval elapsed; |
| |
| switch (which) |
| { |
| default: |
| return __hurd_fail (EINVAL); |
| |
| case ITIMER_VIRTUAL: |
| case ITIMER_PROF: |
| return __hurd_fail (ENOSYS); |
| |
| case ITIMER_REAL: |
| break; |
| } |
| |
| /* Get the time now. */ |
| if (__gettimeofday (&elapsed, NULL) < 0) |
| return -1; |
| |
| /* Extract the current timer setting; and the time it was set, so we can |
| calculate the time elapsed so far. */ |
| HURD_CRITICAL_BEGIN; |
| __spin_lock (&_hurd_itimer_lock); |
| val = _hurd_itimerval; |
| subtract_timeval (&elapsed, &_hurd_itimer_started); |
| __spin_unlock (&_hurd_itimer_lock); |
| HURD_CRITICAL_END; |
| |
| if ((val.it_value.tv_sec | val.it_value.tv_usec) != 0) |
| { |
| /* There is a pending alarm set. VAL indicates the interval it was |
| set for, relative to the time recorded in _hurd_itimer_started. |
| Now compensate for the time elapsed since to get the user's |
| conception of the current value of the timer (as if the value |
| stored decreased every microsecond). */ |
| if (timercmp (&val.it_value, &elapsed, <)) |
| { |
| /* Hmm. The timer should have just gone off, but has not been |
| reset. This is a possible timing glitch. The alarm will signal |
| soon, so fabricate a value for how soon. */ |
| val.it_value.tv_sec = 0; |
| val.it_value.tv_usec = 10; /* Random. */ |
| } |
| else |
| /* Subtract the time elapsed since the timer was set |
| from the current timer value the user sees. */ |
| subtract_timeval (&val.it_value, &elapsed); |
| } |
| |
| *value = val; |
| return 0; |
| } |
| |
| weak_alias (__getitimer, getitimer) |