contrib/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 /*
  16 **  SIGNAL.H -- libsm (and sendmail) signal facilities
  17 **              Extracted from sendmail/conf.h and focusing
  18 **              on signal configuration.
  19 */
  20
  21 #ifndef SM_SIGNAL_H
  22 #define SM_SIGNAL_H 1
  23
  24 #include <sys/types.h>
  25 #include <limits.h>
  26 #include <signal.h>
  27 #include <sm/cdefs.h>
  28 #include <sm/conf.h>
  29
  30 /*
  31 **  Critical signal sections
  32 */
  33
  34 #define PEND_SIGHUP     0x0001
  35 #define PEND_SIGINT     0x0002
  36 #define PEND_SIGTERM    0x0004
  37 #define PEND_SIGUSR1    0x0008
  38
  39 #define ENTER_CRITICAL()        InCriticalSection++
  40
  41 #define LEAVE_CRITICAL()                                                \
  42 do                                                                      \
  43 {                                                                       \
  44         if (InCriticalSection > 0)                                      \
  45                 InCriticalSection--;                                    \
  46 } while (0)
  47
  48 #define CHECK_CRITICAL(sig)                                             \
  49 do                                                                      \
  50 {                                                                       \
  51         if (InCriticalSection > 0 && (sig) != 0)                        \
  52         {                                                               \
  53                 pend_signal((sig));                                     \
  54                 return SIGFUNC_RETURN;                                  \
  55         }                                                               \
  56 } while (0)
  57
  58 /* variables */
  59 extern unsigned int     volatile InCriticalSection;     /* >0 if in critical section */
  60 extern int              volatile PendingSignal; /* pending signal to resend */
  61
  62 /* functions */
  63 extern void             pend_signal __P((int));
  64
  65 /* reset signal in case System V semantics */
  66 #ifdef SYS5SIGNALS
  67 # define FIX_SYSV_SIGNAL(sig, handler)                                  \
  68 {                                                                       \
  69         if ((sig) != 0)                                                 \
  70                 (void) sm_signal((sig), (handler));                     \
  71 }
  72 #else /* SYS5SIGNALS */
  73 # define FIX_SYSV_SIGNAL(sig, handler)  { /* EMPTY */ }
  74 #endif /* SYS5SIGNALS */
  75
  76 extern void             sm_allsignals __P((bool));
  77 extern int              sm_blocksignal __P((int));
  78 extern int              sm_releasesignal __P((int));
  79 extern sigfunc_t        sm_signal __P((int, sigfunc_t));
  80 extern SIGFUNC_DECL     sm_signal_noop __P((int));
  81 #endif /* SM_SIGNAL_H */