sys/sigaction.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
  27  *
  28  *      @(#)sigaction.c 1.0
  29  */
  30
  31 #include <sys/syscall.h>
  32 #include <signal.h>
  33 #include <sys/signal.h>
  34 #include <errno.h>
  35
  36 /*
  37  *      Intercept the sigaction syscall and use our signal trampoline
  38  *      as the signal handler instead.  The code here is derived
  39  *      from sigvec in sys/kern_sig.c.
  40  */
  41
  42 #if defined(__DYNAMIC__)
  43 extern int __in_sigtramp;
  44 #endif
  45
  46 static int
  47 sigaction__ (sig, nsv, osv, bind)
  48         int sig;
  49         register struct sigaction *nsv, *osv;
  50         int bind;
  51 {
  52         struct sigaction vec;
  53         void (*prevsig)();
  54         extern void _sigtramp();
  55         struct __sigaction sa;
  56         struct __sigaction *sap;
  57
  58         if (sig <= 0 || sig >= NSIG || sig == SIGKILL || sig == SIGSTOP) {
  59                 errno = EINVAL;
  60                 return (-1);
  61         }
  62         sap = (struct __sigaction *)0;
  63         if (nsv) {
  64                 sa.sa_handler = nsv->sa_handler;
  65                 sa.sa_tramp = _sigtramp;
  66                 sa.sa_mask = nsv->sa_mask;
  67                 sa.sa_flags = nsv->sa_flags;
  68                 sap = &sa;
  69                 if (nsv->sa_handler != (void (*)())SIG_DFL && nsv->sa_handler != (void (*)())SIG_IGN) {
  70 #ifdef __DYNAMIC__
  71                     if (bind && (__in_sigtramp == 0))                           // XXX
  72                   _dyld_bind_fully_image_containing_address(nsv->sa_handler);
  73 #endif
  74                 }
  75         }
  76         if (syscall (SYS_sigaction, sig, sap, osv) < 0) {
  77                 return (-1);
  78         }
  79         return (0);
  80 }
  81
  82
  83 int
  84 sigaction (sig, nsv, osv)
  85         int sig;
  86         register const struct sigaction *nsv;
  87         register struct sigaction *osv;
  88 {
  89     return sigaction__(sig, nsv, osv, 1);
  90 }
  91
  92 // XXX
  93 #ifdef __DYNAMIC__
  94
  95 int
  96 _sigaction_nobind (sig, nsv, osv)
  97         int sig;
  98         register const struct sigaction *nsv;
  99         register struct sigaction *osv;
 100 {
 101     return sigaction__(sig, nsv, osv, 0);
 102 }
 103 #endif
 104