picnoir/glibc
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

signal: Move sys_siglist to a compat symbol

Browse source 
The symbol was deprecated by strsignal and its usage imposes issues
such as copy relocations.

Its internal name is changed to __sys_siglist and __sys_sigabbrev to
avoid static linking usage.  The compat code is also refactored, since
both Linux and Hurd usage the same strategy: export the same array with
different object sizes.

The libSegfault change avoids calling strsignal on the SIGFAULT signal
handler (the current usage is already sketchy, adding a call that
potentially issue locale internal function is even sketchier).

Checked on x86_64-linux-gnu and i686-linux-gnu. I also run a check-abi
on all affected platforms.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This commit is contained in:
Adhemerval Zanella 2020-04-24 11:09:00 -03:00
parent e4e11b1dba
commit b1ccfc061f
14 changed files with 93 additions and 116 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
NEWS
View file

@ -67,6 +67,12 @@ Deprecated and removed features, and other changes affecting compatibility:
* ldconfig now defaults to the new format for ld.so.cache. glibc has
already supported this format for almost 20 years.
* The deprecated arrays sys_siglist, _sys_siglist, and sys_sigabbrev
are no longer available to newly linked binaries, and their declarations
have been removed from <string.h>. They are exported solely as
compatibility symbols to support old binaries. All programs should use
strsignal instead.
Changes to build and runtime requirements:
* powerpc64le requires GCC 7.4 or newer. This is required for supporting

18
debug/segfault.c
View file

@ -49,20 +49,16 @@
static const char *fname;
/* We better should not use `strerror' since it can call far too many
other functions which might fail. Do it here ourselves. */
/* Print the signal number SIGNAL. Either strerror or strsignal might
call local internal functions and these in turn call far too many
other functions and might even allocate memory which might fail. */
static void
write_strsignal (int fd, int signal)
{
if (signal < 0 || signal >= _NSIG || _sys_siglist[signal] == NULL)
{
char buf[30];
char *ptr = _itoa_word (signal, &buf[sizeof (buf)], 10, 0);
WRITE_STRING ("signal ");
write (fd, buf, &buf[sizeof (buf)] - ptr);
}
else
WRITE_STRING (_sys_siglist[signal]);
char buf[30];
char *ptr = _itoa_word (signal, &buf[sizeof (buf)], 10, 0);
WRITE_STRING ("signal ");
write (fd, buf, &buf[sizeof (buf)] - ptr);
}

4
include/signal.h
View file

@ -12,7 +12,9 @@ libc_hidden_proto (__sigpause)
libc_hidden_proto (raise)
libc_hidden_proto (__libc_current_sigrtmin)
libc_hidden_proto (__libc_current_sigrtmax)
libc_hidden_proto (_sys_siglist)
extern const char * const __sys_siglist[_NSIG];
libc_hidden_proto (__sys_siglist)
/* Now define the internal interfaces. */
extern __sighandler_t __bsd_signal (int __sig, __sighandler_t __handler);

5
manual/signal.texi
View file

@ -880,11 +880,6 @@ to @var{signum}.
This function is a BSD feature, declared in the header file @file{signal.h}.
@end deftypefun
@vindex sys_siglist
There is also an array @code{sys_siglist} which contains the messages
for the various signal codes. This array exists on BSD systems, unlike
@code{strsignal}.
@node Signal Actions
@section Specifying Signal Actions
@cindex signal actions

6
signal/signal.h
View file

@ -284,12 +284,6 @@ extern int sigqueue (__pid_t __pid, int __sig, const union sigval __val)
#ifdef __USE_MISC
/* Names of the signals. This variable exists only for compatibility.
Use `strsignal' instead (see <string.h>). */
extern const char *const _sys_siglist[_NSIG];
extern const char *const sys_siglist[_NSIG];
/* Get machine-dependent `struct sigcontext' and signal subcodes. */
# include <bits/sigcontext.h>

2
stdio-common/psiginfo.c
View file

@ -80,7 +80,7 @@ psiginfo (const siginfo_t *pinfo, const char *s)
const char *desc;
if (pinfo->si_signo >= 0 && pinfo->si_signo < NSIG
&& ((desc = _sys_siglist[pinfo->si_signo]) != NULL
&& ((desc = __sys_siglist[pinfo->si_signo]) != NULL
#ifdef SIGRTMIN
|| (pinfo->si_signo >= SIGRTMIN && pinfo->si_signo < SIGRTMAX)
#endif

2
stdio-common/psignal.c
View file

@ -34,7 +34,7 @@ psignal (int sig, const char *s)
else
colon = ": ";
if (sig >= 0 && sig < NSIG && (desc = _sys_siglist[sig]) != NULL)
if (sig >= 0 && sig < NSIG && (desc = __sys_siglist[sig]) != NULL)
(void) __fxprintf (NULL, "%s%s%s\n", s, colon, _(desc));
else
{

8
stdio-common/siglist.c
View file

@ -20,17 +20,19 @@
#include <signal.h>
#include <libintl.h>
const char *const _sys_siglist[NSIG] =
const char *const __sys_siglist[NSIG] =
{
#define init_sig(sig, abbrev, desc) [sig] = desc,
#include <siglist.h>
#undef init_sig
};
libc_hidden_def (__sys_siglist)
const char *const _sys_sigabbrev[NSIG] =
const char *const __sys_sigabbrev[NSIG] =
{
#define init_sig(sig, abbrev, desc) [sig] = abbrev,
#include <siglist.h>
#undef init_sig
};
#include <siglist-compat.c>

2
string/strsignal.c
View file

@ -51,7 +51,7 @@ strsignal (int signum)
(signum >= SIGRTMIN && signum <= SIGRTMAX) ||
#endif
signum < 0 || signum >= NSIG
|| (desc = _sys_siglist[signum]) == NULL)
|| (desc = __sys_siglist[signum]) == NULL)
{
char *buffer = getbuffer ();
int len;

1
sysdeps/generic/siglist-compat.c Normal file
View file

@ -0,0 +1 @@
/* Empty. */

47
sysdeps/generic/siglist-compat.h Normal file
View file

@ -0,0 +1,47 @@
/* Generic siglist compatibility macro definitions.
Copyright (C) 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 _SIGLIST_COMPAT_H
#define _SIGLIST_COMPAT_H
#include <shlib-compat.h>
#include <limits.h>
/* Define new compat symbols for sys_siglist, _sys_siglist, and sys_sigabbrev
for version VERSION with NUMBERSIG times the number of bytes per long int.
Both _sys_siglist and sys_siglist alias to __sys_siglist while
sys_sigabbrev alias to __sys_sigabbrev. Both target alias are
define in siglist.c. */
#define DEFINE_COMPAT_SIGLIST(NUMBERSIG, VERSION) \
declare_symbol_alias (__ ## VERSION ## _sys_siglist, \
__sys_siglist, \
object, NUMBERSIG * (ULONG_WIDTH / UCHAR_WIDTH)); \
declare_symbol_alias (__ ## VERSION ## sys_siglist, \
__sys_siglist, \
object, NUMBERSIG * (ULONG_WIDTH / UCHAR_WIDTH)); \
declare_symbol_alias (__ ## VERSION ## _sys_sigabbrev, \
__sys_sigabbrev, \
object, NUMBERSIG * (ULONG_WIDTH / UCHAR_WIDTH)); \
compat_symbol (libc, __## VERSION ## _sys_siglist, _sys_siglist, \
VERSION); \
compat_symbol (libc, __## VERSION ## sys_siglist, sys_siglist, \
VERSION); \
compat_symbol (libc, __## VERSION ## _sys_sigabbrev, sys_sigabbrev, \
VERSION); \
#endif

78
sysdeps/gnu/siglist.c
View file

@ -1,78 +0,0 @@
/* Define list of all signal numbers and their names.
Copyright (C) 1997-2020 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/>. */
#include <stddef.h>
#include <signal.h>
#include <libintl.h>
#include <shlib-compat.h>
#include <bits/wordsize.h>
const char *const __new_sys_siglist[NSIG] =
{
#define init_sig(sig, abbrev, desc) [sig] = desc,
#include <siglist.h>
#undef init_sig
};
libc_hidden_ver (__new_sys_siglist, _sys_siglist)
const char *const __new_sys_sigabbrev[NSIG] =
{
#define init_sig(sig, abbrev, desc) [sig] = abbrev,
#include <siglist.h>
#undef init_sig
};
#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
declare_symbol_alias (__old_sys_siglist, __new_sys_siglist, object,
OLD_SIGLIST_SIZE * __WORDSIZE / 8)
declare_symbol_alias (__old_sys_sigabbrev, __new_sys_sigabbrev, object,
OLD_SIGLIST_SIZE * __WORDSIZE / 8)
declare_symbol_alias (_old_sys_siglist, __new_sys_siglist, object,
OLD_SIGLIST_SIZE * __WORDSIZE / 8)
compat_symbol (libc, __old_sys_siglist, _sys_siglist, GLIBC_2_0);
compat_symbol (libc, _old_sys_siglist, sys_siglist, GLIBC_2_0);
compat_symbol (libc, __old_sys_sigabbrev, sys_sigabbrev, GLIBC_2_0);
#endif
#if SHLIB_COMPAT (libc, GLIBC_2_1, GLIBC_2_3_3) && defined OLD2_SIGLIST_SIZE
declare_symbol_alias (__old2_sys_siglist, __new_sys_siglist, object,
OLD2_SIGLIST_SIZE * __WORDSIZE / 8)
declare_symbol_alias (__old2_sys_sigabbrev, __new_sys_sigabbrev, object,
OLD2_SIGLIST_SIZE * __WORDSIZE / 8)
declare_symbol_alias (_old2_sys_siglist, __new_sys_siglist, object,
OLD2_SIGLIST_SIZE * __WORDSIZE / 8)
compat_symbol (libc, __old2_sys_siglist, _sys_siglist, GLIBC_2_1);
compat_symbol (libc, _old2_sys_siglist, sys_siglist, GLIBC_2_1);
compat_symbol (libc, __old2_sys_sigabbrev, sys_sigabbrev, GLIBC_2_1);
strong_alias (__new_sys_siglist, _new_sys_siglist)
versioned_symbol (libc, __new_sys_siglist, _sys_siglist, GLIBC_2_3_3);
versioned_symbol (libc, _new_sys_siglist, sys_siglist, GLIBC_2_3_3);
versioned_symbol (libc, __new_sys_sigabbrev, sys_sigabbrev, GLIBC_2_3_3);
#else
strong_alias (__new_sys_siglist, _new_sys_siglist)
versioned_symbol (libc, __new_sys_siglist, _sys_siglist, GLIBC_2_1);
versioned_symbol (libc, _new_sys_siglist, sys_siglist, GLIBC_2_1);
versioned_symbol (libc, __new_sys_sigabbrev, sys_sigabbrev, GLIBC_2_1);
#endif

13
sysdeps/mach/hurd/siglist.h → sysdeps/mach/hurd/siglist-compat.c
View file

@ -1,4 +1,5 @@
/* Copyright (C) 1999-2020 Free Software Foundation, Inc.
/* Compatibility signal numbers and their names symbols. Hurd version.
Copyright (C) 1997-2020 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
@ -15,8 +16,12 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/* This file is included multiple times. */
#include <siglist-compat.h>
#include_next <siglist.h> /* Get the canonical list. */
#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
DEFINE_COMPAT_SIGLIST (33, GLIBC_2_0)
#endif
#define OLD_SIGLIST_SIZE 33 /* For GLIBC_2.0 binary compatibility. */
#if SHLIB_COMPAT (libc, GLIBC_2_1, GLIBC_2_32)
DEFINE_COMPAT_SIGLIST (NSIG, GLIBC_2_1)
#endif

17
sysdeps/unix/sysv/linux/siglist.h → sysdeps/unix/sysv/linux/siglist-compat.c
View file

@ -1,4 +1,5 @@
/* Copyright (C) 1996-2020 Free Software Foundation, Inc.
/* Compatibility signal numbers and their names symbols. Linux version.
Copyright (C) 1997-2020 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
@ -15,10 +16,16 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/* This file is included multiple times. */
#include <siglist-compat.h>
#include_next <siglist.h> /* Get the canonical list. */
#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
DEFINE_COMPAT_SIGLIST (32, GLIBC_2_0)
#endif
#define OLD_SIGLIST_SIZE 32 /* For GLIBC_2.0 binary compatibility. */
#if SHLIB_COMPAT (libc, GLIBC_2_1, GLIBC_2_3_3)
DEFINE_COMPAT_SIGLIST (64, GLIBC_2_1)
#endif
#define OLD2_SIGLIST_SIZE 64 /* For GLIBC_2.1 binary compatibility. */
#if SHLIB_COMPAT (libc, GLIBC_2_3_3, GLIBC_2_32)
DEFINE_COMPAT_SIGLIST (NSIG, GLIBC_2_3_3)
#endif