otherlibs/unix/signals.c

   1 /***********************************************************************/
   2 /*                                                                     */
   3 /*                           Objective Caml                            */
   4 /*                                                                     */
   5 /*            Xavier Leroy, projet Cristal, INRIA Rocquencourt         */
   6 /*                                                                     */
   7 /*  Copyright 1998 Institut National de Recherche en Informatique et   */
   8 /*  en Automatique.  All rights reserved.  This file is distributed    */
   9 /*  under the terms of the GNU Library General Public License, with    */
  10 /*  the special exception on linking described in file ../../LICENSE.  */
  11 /*                                                                     */
  12 /***********************************************************************/
  13
  14 /* $Id$ */
  15
  16 #include <errno.h>
  17 #include <signal.h>
  18
  19 #include <alloc.h>
  20 #include <fail.h>
  21 #include <memory.h>
  22 #include <mlvalues.h>
  23 #include <signals.h>
  24 #include "unixsupport.h"
  25
  26 #ifndef NSIG
  27 #define NSIG 64
  28 #endif
  29
  30 #ifdef POSIX_SIGNALS
  31
  32 static void decode_sigset(value vset, sigset_t * set)
  33 {
  34   sigemptyset(set);
  35   while (vset != Val_int(0)) {
  36     int sig = caml_convert_signal_number(Int_val(Field(vset, 0)));
  37     sigaddset(set, sig);
  38     vset = Field(vset, 1);
  39   }
  40 }
  41
  42 static value encode_sigset(sigset_t * set)
  43 {
  44   value res = Val_int(0);
  45   int i;
  46
  47   Begin_root(res)
  48     for (i = 1; i < NSIG; i++)
  49       if (sigismember(set, i) > 0) {
  50         value newcons = alloc_small(2, 0);
  51         Field(newcons, 0) = Val_int(caml_rev_convert_signal_number(i));
  52         Field(newcons, 1) = res;
  53         res = newcons;
  54       }
  55   End_roots();
  56   return res;
  57 }
  58
  59 static int sigprocmask_cmd[3] = { SIG_SETMASK, SIG_BLOCK, SIG_UNBLOCK };
  60
  61 CAMLprim value unix_sigprocmask(value vaction, value vset)
  62 {
  63   int how;
  64   sigset_t set, oldset;
  65   int retcode;
  66
  67   how = sigprocmask_cmd[Int_val(vaction)];
  68   decode_sigset(vset, &set);
  69   enter_blocking_section();
  70   retcode = sigprocmask(how, &set, &oldset);
  71   leave_blocking_section();
  72   if (retcode == -1) uerror("sigprocmask", Nothing);
  73   return encode_sigset(&oldset);
  74 }
  75
  76 CAMLprim value unix_sigpending(value unit)
  77 {
  78   sigset_t pending;
  79   if (sigpending(&pending) == -1) uerror("sigpending", Nothing);
  80   return encode_sigset(&pending);
  81 }
  82
  83 CAMLprim value unix_sigsuspend(value vset)
  84 {
  85   sigset_t set;
  86   int retcode;
  87   decode_sigset(vset, &set);
  88   enter_blocking_section();
  89   retcode = sigsuspend(&set);
  90   leave_blocking_section();
  91   if (retcode == -1 && errno != EINTR) uerror("sigsuspend", Nothing);
  92   return Val_unit;
  93 }
  94
  95 #else
  96
  97 CAMLprim value unix_sigprocmask(value vaction, value vset)
  98 { invalid_argument("Unix.sigprocmask not available"); }
  99
 100 CAMLprim value unix_sigpending(value unit)
 101 { invalid_argument("Unix.sigpending not available"); }
 102
 103 CAMLprim value unix_sigsuspend(value vset)
 104 { invalid_argument("Unix.sigsuspend not available"); }
 105
 106 #endif