| /* Sleep for a given number of seconds. POSIX.1 version. |
| Copyright (C) 1991-2014 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 <time.h> |
| #include <unistd.h> |
| #include <errno.h> |
| #include <sys/param.h> |
| |
| |
| /* Make the process sleep for SECONDS seconds, or until a signal arrives |
| and is not ignored. The function returns the number of seconds less |
| than SECONDS which it actually slept (zero if it slept the full time). |
| If a signal handler does a `longjmp' or modifies the handling of the |
| SIGALRM signal while inside `sleep' call, the handling of the SIGALRM |
| signal afterwards is undefined. There is no return value to indicate |
| error, but if `sleep' returns SECONDS, it probably didn't work. */ |
| unsigned int |
| __sleep (unsigned int seconds) |
| { |
| /* This is not necessary but some buggy programs depend on it. */ |
| if (__builtin_expect (seconds == 0, 0)) |
| { |
| #ifdef CANCELLATION_P |
| CANCELLATION_P (THREAD_SELF); |
| #endif |
| return 0; |
| } |
| |
| int save_errno = errno; |
| |
| const unsigned int max |
| = (unsigned int) (((unsigned long int) (~((time_t) 0))) >> 1); |
| struct timespec ts = { 0, 0 }; |
| do |
| { |
| if (sizeof (ts.tv_sec) <= sizeof (seconds)) |
| { |
| /* Since SECONDS is unsigned assigning the value to .tv_sec can |
| overflow it. In this case we have to wait in steps. */ |
| ts.tv_sec += MIN (seconds, max); |
| seconds -= (unsigned int) ts.tv_sec; |
| } |
| else |
| { |
| ts.tv_sec = (time_t) seconds; |
| seconds = 0; |
| } |
| |
| if (__nanosleep (&ts, &ts) < 0) |
| /* We were interrupted. |
| Return the number of (whole) seconds we have not yet slept. */ |
| return seconds + ts.tv_sec; |
| } |
| while (seconds > 0); |
| |
| __set_errno (save_errno); |
| |
| return 0; |
| } |
| weak_alias (__sleep, sleep) |
