usr/src/cmd/sendmail/include/sm/signal.h

   1 /*
   2  * Copyright (c) 1998-2001 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  * Copyright (c) 1983, 1995-1997 Eric P. Allman.  All rights reserved.
   5  * Copyright (c) 1988, 1993
   6  *      The Regents of the University of California.  All rights reserved.
   7  *
   8  * By using this file, you agree to the terms and conditions set
   9  * forth in the LICENSE file which can be found at the top level of
  10  * the sendmail distribution.
  11  *
  12  *      $Id: signal.h,v 1.16 2001/07/20 19:48:21 gshapiro Exp $
  13  */
  14
  15 #pragma ident   "%Z%%M% %I%     %E% SMI"
  16
  17 /*
  18 **  SIGNAL.H -- libsm (and sendmail) signal facilities
  19 **              Extracted from sendmail/conf.h and focusing
  20 **              on signal configuration.
  21 */
  22
  23 #ifndef SM_SIGNAL_H
  24 #define SM_SIGNAL_H 1
  25
  26 #include <sys/types.h>
  27 #include <limits.h>
  28 #include <signal.h>
  29 #include <sm/cdefs.h>
  30 #include <sm/conf.h>
  31
  32 /*
  33 **  Critical signal sections
  34 */
  35
  36 #define PEND_SIGHUP     0x0001
  37 #define PEND_SIGINT     0x0002
  38 #define PEND_SIGTERM    0x0004
  39 #define PEND_SIGUSR1    0x0008
  40
  41 #define ENTER_CRITICAL()        InCriticalSection++
  42
  43 #define LEAVE_CRITICAL()                                                \
  44 do                                                                      \
  45 {                                                                       \
  46         if (InCriticalSection > 0)                                      \
  47                 InCriticalSection--;                                    \
  48 } while (0)
  49
  50 #define CHECK_CRITICAL(sig)                                             \
  51 do                                                                      \
  52 {                                                                       \
  53         if (InCriticalSection > 0 && (sig) != 0)                        \
  54         {                                                               \
  55                 pend_signal((sig));                                     \
  56                 return SIGFUNC_RETURN;                                  \
  57         }                                                               \
  58 } while (0)
  59
  60 /* variables */
  61 extern unsigned int     volatile InCriticalSection;     /* >0 if in critical section */
  62 extern int              volatile PendingSignal; /* pending signal to resend */
  63
  64 /* functions */
  65 extern void             pend_signal __P((int));
  66
  67 /* reset signal in case System V semantics */
  68 #ifdef SYS5SIGNALS
  69 # define FIX_SYSV_SIGNAL(sig, handler)                                  \
  70 {                                                                       \
  71         if ((sig) != 0)                                                 \
  72                 (void) sm_signal((sig), (handler));                     \
  73 }
  74 #else /* SYS5SIGNALS */
  75 # define FIX_SYSV_SIGNAL(sig, handler)  { /* EMPTY */ }
  76 #endif /* SYS5SIGNALS */
  77
  78 extern void             sm_allsignals __P((bool));
  79 extern int              sm_blocksignal __P((int));
  80 extern int              sm_releasesignal __P((int));
  81 extern sigfunc_t        sm_signal __P((int, sigfunc_t));
  82 extern SIGFUNC_DECL     sm_signal_noop __P((int));
  83 #endif /* SM_SIGNAL_H */