glibc/sysdeps/unix/sysv/linux/sigsetops.h
Adhemerval Zanella 566e10aa72 signal: Only handle on NSIG signals on signal functions (BZ #25657)
The upper bits of the sigset_t s not fully initialized in the signal
mask calls that return information from kernel (sigprocmask,
sigpending, and pthread_sigmask), since the exported sigset_t size
(1024 bits) is larger than Linux support one (64 or 128 bits).
It might make sigisemptyset/sigorset/sigandset fail if the mask
is filled prior the call.

This patch changes the internal signal function to handle up to
supported Linux signal number (_NSIG), the remaining bits are
untouched.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2020-04-21 15:10:10 -03:00

108 lines
2.8 KiB
C

/* __sigset_t manipulators. Linux version.
Copyright (C) 1991-2020 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
<https://www.gnu.org/licenses/>. */
#ifndef _SIGSETOPS_H
#define _SIGSETOPS_H 1
#include <signal.h>
/* Return a mask that includes the bit for SIG only. */
# define __sigmask(sig) \
(((unsigned long int) 1) << (((sig) - 1) % (8 * sizeof (unsigned long int))))
/* Return the word index for SIG. */
static inline unsigned long int
__sigword (int sig)
{
return (sig - 1) / (8 * sizeof (unsigned long int));
}
/* Linux sig* functions only handle up to __NSIG_WORDS words instead of
full _SIGSET_NWORDS sigset size. The signal numbers are 1-based, and
bit 0 of a signal mask is for signal 1. */
# define __NSIG_WORDS (_NSIG / (8 * sizeof (unsigned long int )))
static inline void
__sigemptyset (sigset_t *set)
{
int cnt = __NSIG_WORDS;
while (--cnt >= 0)
set->__val[cnt] = 0;
}
static inline void
__sigfillset (sigset_t *set)
{
int cnt = __NSIG_WORDS;
while (--cnt >= 0)
set->__val[cnt] = ~0UL;
}
static inline int
__sigisemptyset (const sigset_t *set)
{
int cnt = __NSIG_WORDS;
int ret = set->__val[--cnt];
while (ret == 0 && --cnt >= 0)
ret = set->__val[cnt];
return ret == 0;
}
static inline void
__sigandset (sigset_t *dest, const sigset_t *left, const sigset_t *right)
{
int cnt = __NSIG_WORDS;
while (--cnt >= 0)
dest->__val[cnt] = left->__val[cnt] & right->__val[cnt];
}
static inline void
__sigorset (sigset_t *dest, const sigset_t *left, const sigset_t *right)
{
int cnt = __NSIG_WORDS;
while (--cnt >= 0)
dest->__val[cnt] = left->__val[cnt] | right->__val[cnt];
}
static inline int
__sigismember (const sigset_t *set, int sig)
{
unsigned long int mask = __sigmask (sig);
unsigned long int word = __sigword (sig);
return set->__val[word] & mask ? 1 : 0;
}
static inline void
__sigaddset (sigset_t *set, int sig)
{
unsigned long int mask = __sigmask (sig);
unsigned long int word = __sigword (sig);
set->__val[word] |= mask;
}
static inline void
__sigdelset (sigset_t *set, int sig)
{
unsigned long int mask = __sigmask (sig);
unsigned long int word = __sigword (sig);
set->__val[word] &= ~mask;
}
#endif /* bits/sigsetops.h */