diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/i386/sigaction.c')
| -rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/i386/sigaction.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/i386/sigaction.c b/REORG.TODO/sysdeps/unix/sysv/linux/i386/sigaction.c new file mode 100644 index 0000000000..0cc9d67ad9 --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/i386/sigaction.c @@ -0,0 +1,129 @@ +/* POSIX.1 `sigaction' call for Linux/i386. + Copyright (C) 1991-2017 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 <sysdep.h> +#include <errno.h> +#include <stddef.h> +#include <signal.h> +#include <string.h> + +#include <sysdep.h> +#include <sys/syscall.h> +#include <ldsodefs.h> + +/* The difference here is that the sigaction structure used in the + kernel is not the same as we use in the libc. Therefore we must + translate it here. */ +#include <kernel_sigaction.h> + +/* We do not globally define the SA_RESTORER flag so do it here. */ +#define SA_RESTORER 0x04000000 + + +/* Using the hidden attribute here does not change the code but it + helps to avoid warnings. */ +#ifdef __NR_rt_sigaction +extern void restore_rt (void) asm ("__restore_rt") attribute_hidden; +#endif +extern void restore (void) asm ("__restore") attribute_hidden; + + +/* If ACT is not NULL, change the action for SIG to *ACT. + If OACT is not NULL, put the old action for SIG in *OACT. */ +int +__libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact) +{ + int result; + + struct kernel_sigaction kact, koact; + + if (act) + { + kact.k_sa_handler = act->sa_handler; + kact.sa_flags = act->sa_flags; + memcpy (&kact.sa_mask, &act->sa_mask, sizeof (sigset_t)); + + if (GLRO(dl_sysinfo_dso) == NULL) + { + kact.sa_flags |= SA_RESTORER; + + kact.sa_restorer = ((act->sa_flags & SA_SIGINFO) + ? &restore_rt : &restore); + } + } + + /* XXX The size argument hopefully will have to be changed to the + real size of the user-level sigset_t. */ + INTERNAL_SYSCALL_DECL (err); + result = INTERNAL_SYSCALL (rt_sigaction, err, 4, + sig, act ? &kact : NULL, + oact ? &koact : NULL, _NSIG / 8); + if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (result, err))) + return INLINE_SYSCALL_ERROR_RETURN_VALUE (INTERNAL_SYSCALL_ERRNO (result, + err)); + else if (oact && result >= 0) + { + oact->sa_handler = koact.k_sa_handler; + memcpy (&oact->sa_mask, &koact.sa_mask, sizeof (sigset_t)); + oact->sa_flags = koact.sa_flags; + oact->sa_restorer = koact.sa_restorer; + } + return result; +} +libc_hidden_def (__libc_sigaction) + +#include <nptl/sigaction.c> + +/* NOTE: Please think twice before making any changes to the bits of + code below. GDB needs some intimate knowledge about it to + recognize them as signal trampolines, and make backtraces through + signal handlers work right. Important are both the names + (__restore and __restore_rt) and the exact instruction sequence. + If you ever feel the need to make any changes, please notify the + appropriate GDB maintainer. */ + +#define RESTORE(name, syscall) RESTORE2 (name, syscall) +#define RESTORE2(name, syscall) \ +asm \ + ( \ + ".text\n" \ + " .align 16\n" \ + "__" #name ":\n" \ + " movl $" #syscall ", %eax\n" \ + " int $0x80" \ + ); + +#ifdef __NR_rt_sigaction +/* The return code for realtime-signals. */ +RESTORE (restore_rt, __NR_rt_sigreturn) +#endif + +/* For the boring old signals. */ +#undef RESTORE2 +#define RESTORE2(name, syscall) \ +asm \ + ( \ + ".text\n" \ + " .align 8\n" \ + "__" #name ":\n" \ + " popl %eax\n" \ + " movl $" #syscall ", %eax\n" \ + " int $0x80" \ + ); + +RESTORE (restore, __NR_sigreturn) |