Override elf_nacl.xr linker script so that libc_pic.os links correctly
[glibc/nacl-glibc.git] / sysdeps / unix / sysv / sigaction.c
blobe90b2a85499dd48d396014c4bc29ca4eac645fea
1 /* Copyright (C) 1992,1994,1995,1996,1997,2002 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
19 #include <sysdep.h>
20 #include <errno.h>
21 #include <stddef.h>
22 #include <signal.h>
25 /* If ACT is not NULL, change the action for SIG to *ACT.
26 If OACT is not NULL, put the old action for SIG in *OACT. */
27 int
28 __sigaction (sig, act, oact)
29 int sig;
30 const struct sigaction *act;
31 struct sigaction *oact;
33 sighandler_t handler;
34 int save;
36 if (sig <= 0 || sig >= NSIG)
38 __set_errno (EINVAL);
39 return -1;
42 if (act == NULL)
44 if (oact == NULL)
45 return 0;
46 /* Race condition, but this is the only way to do it. */
47 handler = signal (sig, SIG_IGN);
48 if (handler == SIG_ERR)
49 return -1;
50 save = errno;
51 (void) signal (sig, handler);
52 __set_errno (save);
54 else
56 int i;
58 if (act->sa_flags != 0)
60 unimplemented:
61 __set_errno (ENOSYS);
62 return -1;
65 for (i = 1; i < NSIG; ++i)
66 if (__sigismember (&act->sa_mask, i))
67 goto unimplemented;
69 handler = signal (sig, act->sa_handler);
70 if (handler == SIG_ERR)
71 return -1;
74 if (oact != NULL)
76 oact->sa_handler = handler;
77 __sigemptyset (&oact->sa_mask);
78 oact->sa_flags = 0;
81 return 0;
83 libc_hidden_def (__sigaction)
84 weak_alias (__sigaction, sigaction)