Line data    Source code

       1             : This file is suspend.def, from which is created suspend.c.
       2             : It implements the builtin "suspend" in Bash.
       3             : 
       4             : Copyright (C) 1987-2015 Free Software Foundation, Inc.
       5             : 
       6             : This file is part of GNU Bash, the Bourne Again SHell.
       7             : 
       8             : Bash is free software: you can redistribute it and/or modify
       9             : it under the terms of the GNU General Public License as published by
      10             : the Free Software Foundation, either version 3 of the License, or
      11             : (at your option) any later version.
      12             : 
      13             : Bash is distributed in the hope that it will be useful,
      14             : but WITHOUT ANY WARRANTY; without even the implied warranty of
      15             : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      16             : GNU General Public License for more details.
      17             : 
      18             : You should have received a copy of the GNU General Public License
      19             : along with Bash.  If not, see <http://www.gnu.org/licenses/>.
      20             : 
      21             : $PRODUCES suspend.c
      22             : 
      23             : $BUILTIN suspend
      24             : $DEPENDS_ON JOB_CONTROL
      25             : $FUNCTION suspend_builtin
      26             : $SHORT_DOC suspend [-f]
      27             : Suspend shell execution.
      28             : 
      29             : Suspend the execution of this shell until it receives a SIGCONT signal.
      30             : Unless forced, login shells cannot be suspended.
      31             : 
      32             : Options:
      33             :   -f    force the suspend, even if the shell is a login shell
      34             : 
      35             : Exit Status:
      36             : Returns success unless job control is not enabled or an error occurs.
      37             : $END
      38             : 
      39             : #include <config.h>
      40             : 
      41             : #if defined (JOB_CONTROL)
      42             : #if defined (HAVE_UNISTD_H)
      43             : #  ifdef _MINIX
      44             : #    include <sys/types.h>
      45             : #  endif
      46             : #  include <unistd.h>
      47             : #endif
      48             : 
      49             : #include "../bashtypes.h"
      50             : #include <signal.h>
      51             : #include "../bashintl.h"
      52             : #include "../shell.h"
      53             : #include "../jobs.h"
      54             : #include "common.h"
      55             : #include "bashgetopt.h"
      56             : 
      57             : static sighandler suspend_continue __P((int));
      58             : 
      59             : static SigHandler *old_cont;
      60             : #if 0
      61             : static SigHandler *old_stop;
      62             : #endif
      63             : 
      64             : /* Continue handler. */
      65             : static sighandler
      66           0 : suspend_continue (sig)
      67             :      int sig;
      68             : {
      69           0 :   set_signal_handler (SIGCONT, old_cont);
      70             : #if 0
      71             :   set_signal_handler (SIGSTOP, old_stop);
      72             : #endif
      73           0 :   SIGRETURN (0);
      74             : }
      75             : 
      76             : /* Suspending the shell.  If -f is the arg, then do the suspend
      77             :    no matter what.  Otherwise, complain if a login shell. */
      78             : int
      79          50 : suspend_builtin (list)
      80             :      WORD_LIST *list;
      81             : {
      82          50 :   int opt, force;
      83             : 
      84          50 :   reset_internal_getopt ();
      85          50 :   force = 0;
      86          50 :   while ((opt = internal_getopt (list, "f")) != -1)
      87           0 :     switch (opt)
      88             :       {
      89           0 :       case 'f':
      90           0 :         force++;
      91           0 :         break;
      92           0 :       CASE_HELPOPT;
      93           0 :       default:
      94           0 :         builtin_usage ();
      95           0 :         return (EX_USAGE);
      96             :       }
      97             :       
      98          50 :   list = loptend;
      99             : 
     100          50 :   if (job_control == 0)
     101             :     {
     102          50 :       sh_nojobs (_("cannot suspend"));
     103          50 :       return (EXECUTION_FAILURE);
     104             :     }
     105             : 
     106           0 :   if (force == 0)  
     107             :     {
     108           0 :       no_args (list);
     109             : 
     110           0 :       if (login_shell)
     111             :         {
     112           0 :           builtin_error (_("cannot suspend a login shell"));
     113           0 :           return (EXECUTION_FAILURE);
     114             :         }
     115             :     }
     116             : 
     117             :   /* XXX - should we put ourselves back into the original pgrp now?  If so,
     118             :      call end_job_control() here and do the right thing in suspend_continue
     119             :      (that is, call restart_job_control()). */
     120           0 :   old_cont = (SigHandler *)set_signal_handler (SIGCONT, suspend_continue);
     121             : #if 0
     122             :   old_stop = (SigHandler *)set_signal_handler (SIGSTOP, SIG_DFL);
     123             : #endif
     124           0 :   killpg (shell_pgrp, SIGSTOP);
     125           0 :   return (EXECUTION_SUCCESS);
     126             : }
     127             : 
     128             : #endif /* JOB_CONTROL */