1  /*
       2   * exec_shell() - launch a shell, else exit!
       3   *
       4   * This program is free software; you can redistribute it and/or modify it
       5   * under the terms of the GNU General Public License as published by the
       6   * Free Software Foundation; either version 2, or (at your option) any
       7   * later version.
       8   *
       9   * This program is distributed in the hope that it will be useful, but
      10   * WITHOUT ANY WARRANTY; without even the implied warranty of
      11   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12   * General Public License for more details.
      13   *
      14   * You should have received a copy of the GNU General Public License along
      15   * with this program; if not, write to the Free Software Foundation, Inc.,
      16   * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
      17   */
      18  
      19  #include <stdlib.h>
      20  #include <string.h>
      21  #include <unistd.h>
      22  #include <sys/types.h>
      23  #include <libgen.h>
      24  
      25  #include "nls.h"
      26  #include "c.h"
      27  #include "xalloc.h"
      28  
      29  #include "exec_shell.h"
      30  
      31  #define DEFAULT_SHELL "/bin/sh"
      32  
      33  void __attribute__((__noreturn__)) exec_shell(void)
      34  {
      35  	const char *shell = getenv("SHELL");
      36  	char *shellc;
      37  	const char *shell_basename;
      38  	char *arg0;
      39  
      40  	if (!shell)
      41  		shell = DEFAULT_SHELL;
      42  
      43  	shellc = xstrdup(shell);
      44  	shell_basename = basename(shellc);
      45  	arg0 = xmalloc(strlen(shell_basename) + 2);
      46  	arg0[0] = '-';
      47  	strcpy(arg0 + 1, shell_basename);
      48  
      49  	execl(shell, arg0, (char *)NULL);
      50  	errexec(shell);
      51  }