sys/sigaction.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
  25  *
  26  *      @(#)sigaction.c 1.0
  27  */
  28
  29 #include <sys/syscall.h>
  30 #include <unistd.h>
  31 #include <signal.h>
  32 #include <sys/signal.h>
  33 #include <errno.h>
  34
  35 /*
  36  *      Intercept the sigaction syscall and use our signal trampoline
  37  *      as the signal handler instead.  The code here is derived
  38  *      from sigvec in sys/kern_sig.c.
  39  */
  40
  41 #if defined(__DYNAMIC__)
  42 extern int __in_sigtramp;
  43 #endif
  44
  45 static int
  46 sigaction__ (sig, nsv, osv, bind)
  47         int sig;
  48         register struct sigaction *nsv, *osv;
  49         int bind;
  50 {
  51         extern void _sigtramp();
  52         struct __sigaction sa;
  53         struct __sigaction *sap;
  54
  55         if (sig <= 0 || sig >= NSIG || sig == SIGKILL || sig == SIGSTOP) {
  56                 errno = EINVAL;
  57                 return (-1);
  58         }
  59         sap = (struct __sigaction *)0;
  60         if (nsv) {
  61                 sa.sa_handler = nsv->sa_handler;
  62                 sa.sa_tramp = _sigtramp;
  63                 sa.sa_mask = nsv->sa_mask;
  64                 sa.sa_flags = nsv->sa_flags;
  65                 sap = &sa;
  66                 if (nsv->sa_handler != (void (*)())SIG_DFL && nsv->sa_handler != (void (*)())SIG_IGN) {
  67 #ifdef __DYNAMIC__
  68                     if (bind && (__in_sigtramp == 0))                           // XXX
  69                   _dyld_bind_fully_image_containing_address(nsv->sa_handler);
  70 #endif
  71                 }
  72         }
  73         if (syscall (SYS_sigaction, sig, sap, osv) < 0) {
  74                 return (-1);
  75         }
  76         return (0);
  77 }
  78
  79
  80 int
  81 sigaction (sig, nsv, osv)
  82         int sig;
  83         register const struct sigaction *nsv;
  84         register struct sigaction *osv;
  85 {
  86     return sigaction__(sig, nsv, osv, 1);
  87 }
  88
  89 // XXX
  90 #ifdef __DYNAMIC__
  91
  92 int
  93 _sigaction_nobind (sig, nsv, osv)
  94         int sig;
  95         register const struct sigaction *nsv;
  96         register struct sigaction *osv;
  97 {
  98     return sigaction__(sig, nsv, osv, 0);
  99 }
 100 #endif
 101