X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fnanosleep.c;h=58fc7881eceedd4be36c145d516827879ba58195;hb=74a9f8aecf503bc6a6a1f955cc847a82b31ddbd4;hp=b51f648c7ab7803ec2f742f3788a7e9c46f3a6a5;hpb=bff644dff2de356fa3c2a99456216caf5c3e9ee0;p=gnulib.git diff --git a/lib/nanosleep.c b/lib/nanosleep.c index b51f648c7..58fc7881e 100644 --- a/lib/nanosleep.c +++ b/lib/nanosleep.c @@ -1,10 +1,11 @@ /* Provide a replacement for the POSIX nanosleep function. - Copyright (C) 1999 Free Software Foundation, Inc. - This program is free software; you can redistribute it and/or modify + Copyright (C) 1999-2000, 2002, 2004-2010 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2, or (at your option) - any later version. + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -12,87 +13,165 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software Foundation, - Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + along with this program. If not, see . */ /* written by Jim Meyering */ #include + +#include + +#include "intprops.h" +#include "sig-handler.h" +#include "verify.h" + +#include #include #include +#include #include -#include -/* FIXME: is including both like this kosher? */ #include +#include -static interrupted; +#include -/* Handle SIGCONT. */ +#undef nanosleep -static void -sighandler (int sig) +enum { BILLION = 1000 * 1000 * 1000 }; + +#if HAVE_BUG_BIG_NANOSLEEP + +int +rpl_nanosleep (const struct timespec *requested_delay, + struct timespec *remaining_delay) { -#ifdef SA_INTERRUPT - struct sigaction sigact; + /* nanosleep mishandles large sleeps due to internal overflow + problems. The worst known case of this is cygwin 1.5.x, which + can't sleep more than 49.7 days (2**32 milliseconds). Solve this + by breaking the sleep up into smaller chunks. Verify that time_t + is large enough. */ + verify (TYPE_MAXIMUM (time_t) / 49 / 24 / 60 / 60); + const time_t limit = 49 * 24 * 60 * 60; + time_t seconds = requested_delay->tv_sec; + struct timespec intermediate; + intermediate.tv_nsec = 0; + + while (limit < seconds) + { + int result; + intermediate.tv_sec = limit; + result = nanosleep (&intermediate, remaining_delay); + seconds -= limit; + if (result) + { + if (remaining_delay) + { + remaining_delay->tv_sec += seconds; + remaining_delay->tv_nsec += requested_delay->tv_nsec; + if (BILLION <= requested_delay->tv_nsec) + { + remaining_delay->tv_sec++; + remaining_delay->tv_nsec -= BILLION; + } + } + return result; + } + } + intermediate.tv_sec = seconds; + intermediate.tv_nsec = requested_delay->tv_nsec; + return nanosleep (&intermediate, remaining_delay); +} - sigact.sa_handler = SIG_DFL; - sigemptyset (&sigact.sa_mask); - sigact.sa_flags = 0; - sigaction (sig, &sigact, NULL); #else - signal (sig, SIG_DFL); -#endif +/* Some systems (MSDOS) don't have SIGCONT. + Using SIGTERM here turns the signal-handling code below + into a no-op on such systems. */ +# ifndef SIGCONT +# define SIGCONT SIGTERM +# endif + +static sig_atomic_t volatile suspended; + +/* Handle SIGCONT. */ + +static void +sighandler (int sig) +{ suspended = 1; - kill (getpid (), sig); } -/* Sleep for USEC microseconds. */ +/* Suspend execution for at least *TS_DELAY seconds. */ static void -usleep (const struct timespec *ts_delay) +my_usleep (const struct timespec *ts_delay) { struct timeval tv_delay; tv_delay.tv_sec = ts_delay->tv_sec; - tv_delay.tv_usec = 1000 * ts_delay->tv_nsec; - select (0, (void *) 0, (void *) 0, (void *) 0, tv_delay); + tv_delay.tv_usec = (ts_delay->tv_nsec + 999) / 1000; + if (tv_delay.tv_usec == 1000000) + { + time_t t1 = tv_delay.tv_sec + 1; + if (t1 < tv_delay.tv_sec) + tv_delay.tv_usec = 1000000 - 1; /* close enough */ + else + { + tv_delay.tv_sec = t1; + tv_delay.tv_usec = 0; + } + } + select (0, NULL, NULL, NULL, &tv_delay); } +/* Suspend execution for at least *REQUESTED_DELAY seconds. The + *REMAINING_DELAY part isn't implemented yet. */ + int -nanosleep (const struct timespec *requested_delay, - struct timespec *remaining_delay) +rpl_nanosleep (const struct timespec *requested_delay, + struct timespec *remaining_delay) { -#ifdef SA_INTERRUPT - struct sigaction oldact, newact; -#endif + static bool initialized; - interrupted = 0; + if (requested_delay->tv_nsec < 0 || BILLION <= requested_delay->tv_nsec) + { + errno = EINVAL; + return -1; + } - /* set up sig handler -- but maybe only do this the first time? */ -#ifdef SA_INTERRUPT - newact.sa_handler = sighandler; - sigemptyset (&newact.sa_mask); - newact.sa_flags = 0; + /* set up sig handler */ + if (! initialized) + { + struct sigaction oldact; + + sigaction (SIGCONT, NULL, &oldact); + if (get_handler (&oldact) != SIG_IGN) + { + struct sigaction newact; + + newact.sa_handler = sighandler; + sigemptyset (&newact.sa_mask); + newact.sa_flags = 0; + sigaction (SIGCONT, &newact, NULL); + } + initialized = true; + } - sigaction (SIGCONT, NULL, &oldact); - if (oldact.sa_handler != SIG_IGN) - sigaction (SIGCONT, &newact, NULL); -#else - if (signal (SIGCONT, SIG_IGN) != SIG_IGN) - signal (SIGCONT, sighandler); -#endif + suspended = 0; - usleep (requested_delay); + my_usleep (requested_delay); - if (interrupted) + if (suspended) { /* Calculate time remaining. */ /* FIXME: the code in sleep doesn't use this, so there's no - rush to implement it. */ + rush to implement it. */ + + errno = EINTR; } /* FIXME: Restore sig handler? */ - return interrupted; + return suspended; } +#endif