pico/osdep/signals.c

   1 /*
   2  * ========================================================================
   3  * Copyright 2006-2007 University of Washington
   4  * Copyright 2013-2022 Eduardo Chappa
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * ========================================================================
  13  */
  14
  15 #include <system.h>
  16 #include <general.h>
  17
  18 #include "../headers.h"
  19
  20 #include "../../pith/charconv/filesys.h"
  21
  22 #include "tty.h"
  23
  24 #include "signals.h"
  25
  26
  27 /* internal prototypes */
  28 #ifndef _WINDOWS
  29 RETSIGTYPE      do_hup_signal(int);
  30 #endif
  31
  32
  33 /*
  34  * picosigs - Install any handlers for the signals we're interested
  35  *            in catching.
  36  */
  37 void
  38 picosigs(void)
  39 {
  40 #ifndef _WINDOWS
  41     signal(SIGHUP,  do_hup_signal);     /* deal with SIGHUP */
  42     signal(SIGTERM, do_hup_signal);     /* deal with SIGTERM */
  43 #ifdef  SIGTSTP
  44     signal(SIGTSTP, SIG_DFL);
  45 #endif
  46 #if     defined(SIGWINCH) && defined(TIOCGWINSZ)
  47     signal(SIGWINCH, winch_handler); /* window size changes */
  48 #endif
  49 #endif /* !_WINDOWS */
  50 }
  51
  52
  53
  54
  55 #ifndef _WINDOWS
  56 /*
  57  * do_hup_signal - jump back in the stack to where we can handle this
  58  */
  59 RETSIGTYPE
  60 do_hup_signal(int sig)
  61 {
  62     signal(SIGHUP,  SIG_IGN);                   /* ignore further SIGHUP's */
  63     signal(SIGTERM, SIG_IGN);                   /* ignore further SIGTERM's */
  64     if(Pmaster){
  65         extern jmp_buf finstate;
  66
  67         longjmp(finstate, COMP_GOTHUP);
  68     }
  69     else{
  70         /*
  71          * if we've been interrupted and the buffer is changed,
  72          * save it...
  73          */
  74         if(anycb() == TRUE){                    /* time to save */
  75             if(curbp->b_fname[0] == '\0'){      /* name it */
  76                 strncpy(curbp->b_fname, "pico.save", sizeof(curbp->b_fname));
  77                 curbp->b_fname[sizeof(curbp->b_fname)-1] = '\0';
  78             }
  79             else{
  80                 strncat(curbp->b_fname, ".save", sizeof(curbp->b_fname)-strlen(curbp->b_fname)-1);
  81                 curbp->b_fname[sizeof(curbp->b_fname)-1] = '\0';
  82             }
  83
  84             our_unlink(curbp->b_fname);
  85             writeout(curbp->b_fname, TRUE);
  86         }
  87
  88         vttidy();
  89         exit(1);
  90     }
  91 }
  92 #endif /* !_WINDOWS */
  93
  94
  95 #if     defined(SIGWINCH) && defined(TIOCGWINSZ)
  96 /*
  97  * winch_handler - handle window change signal
  98  */
  99 RETSIGTYPE
 100 winch_handler(int sig)
 101 {
 102     int i = 0;
 103     signal(SIGWINCH, winch_handler);
 104     if(wheadp != NULL)
 105       ttresize();
 106     else if (Pmaster){
 107       i = Pmaster->arm_winch_cleanup;
 108       Pmaster->arm_winch_cleanup = 1;
 109     }
 110     if(Pmaster && Pmaster->winch_cleanup && Pmaster->arm_winch_cleanup)
 111       (*Pmaster->winch_cleanup)();
 112     if(wheadp == NULL && Pmaster != NULL)
 113         Pmaster->arm_winch_cleanup = i;
 114 }
 115 #endif  /* SIGWINCH and friends */
 116
 117
 118
 119 #ifdef  POSIX_SIGNALS
 120 /*----------------------------------------------------------------------
 121    Reset signals after critical imap code
 122  ----*/
 123 void
 124 (*posix_signal(int sig_num, RETSIGTYPE (*action)(int)))(int)
 125 {
 126     struct sigaction new_action, old_action;
 127
 128     memset((void *)&new_action, 0, sizeof(struct sigaction));
 129     sigemptyset (&new_action.sa_mask);
 130     new_action.sa_handler = action;
 131 #ifdef  SA_RESTART
 132     new_action.sa_flags = SA_RESTART;
 133 #else
 134     new_action.sa_flags = 0;
 135 #endif
 136     sigaction(sig_num, &new_action, &old_action);
 137     return(old_action.sa_handler);
 138 }
 139
 140 int
 141 posix_sigunblock(int mask)
 142 {
 143     sigset_t sig_mask;
 144
 145     sigemptyset(&sig_mask);
 146     sigaddset(&sig_mask, mask);
 147 #if     HAVE_PTHREAD
 148 # define sigprocmask    pthread_sigmask
 149 #endif
 150     return(sigprocmask(SIG_UNBLOCK, &sig_mask, NULL));
 151 }
 152 #endif /* POSIX_SIGNALS */
 153
 154
 155 #if     defined(sv3) || defined(ct)
 156 /* Placed by rll to handle the rename function not found in AT&T */
 157 int
 158 rename(char *oldname, char *newname)
 159 {
 160     int rtn;
 161     char b[NLINE];
 162
 163     strncpy(b, fname_to_locale(oldname), sizeof(b));
 164     b[sizeof(b)-1] = '\0';
 165
 166     if ((rtn = link(b, fname_to_locale(newname))) != 0) {
 167         perror("Was not able to rename file.");
 168         return(rtn);
 169     }
 170
 171     if ((rtn = our_unlink(b)) != 0)
 172       perror("Was not able to unlink file.");
 173
 174     return(rtn);
 175 }
 176 #endif
 177