1  /* operand2sig.c -- common function for parsing signal specifications
       2     Copyright (C) 2008-2023 Free Software Foundation, Inc.
       3  
       4     This program is free software: you can redistribute it and/or modify
       5     it under the terms of the GNU General Public License as published by
       6     the Free Software Foundation, either version 3 of the License, or
       7     (at your option) any later version.
       8  
       9     This program is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12     GNU General Public License for more details.
      13  
      14     You should have received a copy of the GNU General Public License
      15     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      16  
      17  /* Extracted from kill.c/timeout.c by Pádraig Brady.
      18     FIXME: Move this to gnulib/str2sig.c */
      19  
      20  
      21  /* Convert OPERAND to a signal number with printable representation SIGNAME.
      22     Return the signal number, or -1 if unsuccessful.  */
      23  
      24  #include <config.h>
      25  #include <stdio.h>
      26  #include <sys/types.h>
      27  #include <sys/wait.h>
      28  
      29  #include "system.h"
      30  #include "quote.h"
      31  #include "sig2str.h"
      32  #include "operand2sig.h"
      33  
      34  extern int
      35  operand2sig (char const *operand, char *signame)
      36  {
      37    int signum;
      38  
      39    if (ISDIGIT (*operand))
      40      {
      41        /* Note we don't put a limit on the maximum value passed,
      42           because we're checking shell $? values here, and ksh for
      43           example will add 256 to the signal value, thus being wider
      44           than the number of WEXITSTATUS bits.
      45           We could validate that values were not above say
      46           ((WEXITSTATUS (~0) << 1) + 1), which would cater for ksh.
      47           But some shells may use other adjustments in future to be
      48           (forward) compatible with systems that support
      49           wider exit status values as discussed at
      50           https://austingroupbugs.net/view.php?id=947  */
      51  
      52        char *endp;
      53        long int l = (errno = 0, strtol (operand, &endp, 10));
      54        int i = l;
      55        signum = (operand == endp || *endp || errno || i != l ? -1 : i);
      56  
      57        if (signum != -1)
      58          {
      59            /* Note AIX uses a different bit pattern for status returned
      60               from shell and wait(), so we can't use WTERMSIG etc. here.
      61               Also ksh returns 0xFF + signal number.  */
      62            signum &= signum >= 0xFF ? 0xFF : 0x7F;
      63          }
      64      }
      65    else
      66      {
      67        /* Convert signal to upper case in the C locale, not in the
      68           current locale.  Don't assume ASCII; it might be EBCDIC.  */
      69        char *upcased = xstrdup (operand);
      70        char *p;
      71        for (p = upcased; *p; p++)
      72          if (strchr ("abcdefghijklmnopqrstuvwxyz", *p))
      73            *p += 'A' - 'a';
      74  
      75        /* Look for the signal name, possibly prefixed by "SIG",
      76           and possibly lowercased.  */
      77        if (!(str2sig (upcased, &signum) == 0
      78              || (upcased[0] == 'S' && upcased[1] == 'I' && upcased[2] == 'G'
      79                  && str2sig (upcased + 3, &signum) == 0)))
      80          signum = -1;
      81  
      82        free (upcased);
      83      }
      84  
      85    if (signum < 0 || sig2str (signum, signame) != 0)
      86      {
      87        error (0, 0, _("%s: invalid signal"), quote (operand));
      88        return -1;
      89      }
      90  
      91    return signum;
      92  }