mirror of
https://sourceware.org/git/glibc.git
synced 2024-09-29 10:37:50 +00:00
7a1147946e
2003-06-15 Ulrich Drepper <drepper@redhat.com> Fix cancellation point handling wrt exception based cleanup. * io/Makefile: Compile fcntl.c, poll.c, and lockf.c with exceptions. * misc/Makefile: Compile pselect.c, readv.c, writev.c, and usleep.c with exceptions. * posix/Makefile: Compile pread.c, pread64.c, pwrite.c, pwrite64.c, sleep.c, wait.c, waitid.c, and waitpid.c with exceptions. * rt/Makefile: Compile aio_suspend.c and clock_nanosleep.c with exceptions. * signal/Makefile: Compile sigpause.c, sigsuspend.c, sigtimedwait.c, sigwait.c, and sigwaitinfo.c with exceptions. * stdlib/Makefile: Compile system.c with exceptions. * sysvipc/Makefile: Compile msgrcv.c and msgsnd.c with exceptions. * termios/Makefile: Compile tcdrain.c with exceptions. * sysdeps/generic/lockf.c: Add comment explaining the cancellation situation. * sysdeps/generic/pselect.c: Likewise. * sysdeps/posix/sigpause.c: Likewise. * sysdeps/posix/system.c: Likewise. * sysdeps/posix/waitid.c: Likewise. * sysdeps/unix/sysv/linux/sleep.c: Likewise. * sysdeps/unix/sysv/linux/usleep.c: Likewise. * sysdeps/unix/sysv/linux/i386/sysdep.h: Major rewrite of INTERNAL_SYSCALL to not use push inside asm statement so that unwind info is correct around the syscall. * sysdeps/unix/clock_nanosleep.c: Add cancellation support. * sysdeps/unix/sysv/linux/clock_nanosleep.c: Likewise.
75 lines
2.1 KiB
C
75 lines
2.1 KiB
C
/* Copyright (C) 1994,1996,1997,1998,2000,2003 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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <errno.h>
|
|
#include <string.h>
|
|
|
|
/* lockf is a simplified interface to fcntl's locking facilities. */
|
|
|
|
int
|
|
lockf (int fd, int cmd, off_t len)
|
|
{
|
|
struct flock fl;
|
|
|
|
memset ((char *) &fl, '\0', sizeof (fl));
|
|
|
|
/* lockf is always relative to the current file position. */
|
|
fl.l_whence = SEEK_CUR;
|
|
fl.l_start = 0;
|
|
fl.l_len = len;
|
|
|
|
switch (cmd)
|
|
{
|
|
case F_TEST:
|
|
/* Test the lock: return 0 if FD is unlocked or locked by this process;
|
|
return -1, set errno to EACCES, if another process holds the lock. */
|
|
fl.l_type = F_RDLCK;
|
|
if (__fcntl (fd, F_GETLK, &fl) < 0)
|
|
return -1;
|
|
if (fl.l_type == F_UNLCK || fl.l_pid == __getpid ())
|
|
return 0;
|
|
__set_errno (EACCES);
|
|
return -1;
|
|
|
|
case F_ULOCK:
|
|
fl.l_type = F_UNLCK;
|
|
cmd = F_SETLK;
|
|
break;
|
|
case F_LOCK:
|
|
fl.l_type = F_WRLCK;
|
|
cmd = F_SETLKW;
|
|
break;
|
|
case F_TLOCK:
|
|
fl.l_type = F_WRLCK;
|
|
cmd = F_SETLK;
|
|
break;
|
|
|
|
default:
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
|
|
/* lockf() is a cancellation point but so is fcntl() if F_SETLKW is
|
|
used. Therefore we don't have to care about cancellation here,
|
|
the fcntl() function will take care of it. */
|
|
return __fcntl (fd, cmd, &fl);
|
|
}
|