shell.cc

/* shell.c -- readline utility functions that are normally provided by
        bash when readline is linked as part of the shell. */

/* Copyright (C) 1997-2009,2017 Free Software Foundation, Inc.

   This file is part of the GNU Readline Library (Readline), a library
   for reading lines of text with interactive input and history editing.

   Readline is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   Readline is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with Readline.  If not, see <http://www.gnu.org/licenses/>.
*/

#define READLINE_LIBRARY

#if defined(HAVE_CONFIG_H)
#include <config.hh>
#endif

#include <sys/types.h>

#if defined(HAVE_UNISTD_H)
#include <unistd.h>
#endif /* HAVE_UNISTD_H */

#if defined(HAVE_STDLIB_H)
#include <stdlib.h>
#else
#include "ansi_stdlib.hh"
#endif /* HAVE_STDLIB_H */

#if defined(HAVE_STRING_H)
#include <string.h>
#else
#include <strings.h>
#endif /* !HAVE_STRING_H */

#if defined(HAVE_LIMITS_H)
#include <limits.h>
#endif

#if defined(HAVE_FCNTL_H)
#include <fcntl.h>
#endif
#if defined(HAVE_PWD_H)
#include <pwd.h>
#endif

#include <stdio.h>

#include "rldefs.hh"
#include "rlshell.hh"
#include "rlstdc.hh"

#include "xmalloc.hh"

#if defined(HAVE_GETPWUID) && !defined(HAVE_GETPW_DECLS)
extern struct passwd* getpwuid PARAMS((uid_t));
#endif /* HAVE_GETPWUID && !HAVE_GETPW_DECLS */

#ifndef NULL
#define NULL 0
#endif

#ifndef CHAR_BIT
#define CHAR_BIT 8
#endif

/* Nonzero if the integer type T is signed.  */
#define TYPE_SIGNED(t) (!((t)0 < (t)-1))

/* Bound on length of the string representing an integer value of type T.
   Subtract one for the sign bit if T is signed;
   302 / 1000 is log10 (2) rounded up;
   add one for integer division truncation;
   add one more for a minus sign if t is signed.  */
#define INT_STRLEN_BOUND(t)                                               \
  ((sizeof(t) * CHAR_BIT - TYPE_SIGNED(t)) * 302 / 1000 + 1 +             \
   TYPE_SIGNED(t))

/* All of these functions are resolved from bash if we are linking readline
   as part of bash. */

/* Does shell-like quoting using single quotes. */
char* sh_single_quote(char* string)
{
   int c;
  char *       result, *r, *s;

  result= (char*)xmalloc(3 + (4 * strlen(string)));
  r     = result;
  *r++  = '\'';

  for (s= string; s && (c= *s); s++)
  {
    *r++= c;

    if (c == '\'')
    {
      *r++= '\\'; /* insert escaped single quote */
      *r++= '\'';
      *r++= '\''; /* start new quoted string */
    }
  }

  *r++= '\'';
  *r  = '\0';

  return (result);
}

/* Set the environment variables LINES and COLUMNS to lines and cols,
   respectively. */
static char setenv_buf[INT_STRLEN_BOUND(int) + 1];
static char putenv_buf1[INT_STRLEN_BOUND(int) + 6 +
                        1]; /* sizeof("LINES=") == 6 */
static char putenv_buf2[INT_STRLEN_BOUND(int) + 8 +
                        1]; /* sizeof("COLUMNS=") == 8 */

void sh_set_lines_and_columns(int lines, int cols)
{
#if defined(HAVE_SETENV)
  sprintf(setenv_buf, "%d", lines);
  setenv("LINES", setenv_buf, 1);

  sprintf(setenv_buf, "%d", cols);
  setenv("COLUMNS", setenv_buf, 1);
#else /* !HAVE_SETENV */
#if defined(HAVE_PUTENV)
  sprintf(putenv_buf1, "LINES=%d", lines);
  putenv(putenv_buf1);

  sprintf(putenv_buf2, "COLUMNS=%d", cols);
  putenv(putenv_buf2);
#endif /* HAVE_PUTENV */
#endif /* !HAVE_SETENV */
}

char* sh_get_env_value(const char* varname)
{
  return ((char*)getenv(varname));
}

char* sh_get_home_dir(void)
{
#if 0
  static char *home_dir = (char *)NULL;
  struct passwd *entry;

  if (home_dir)
    return (home_dir);

  home_dir = (char *)NULL;
#if defined(HAVE_GETPWUID)
#if defined(__TANDEM)
  entry = getpwnam (getlogin ());
#else
  entry = getpwuid (getuid ());
#endif
  if (entry)
    home_dir = savestring (entry->pw_dir);
#endif

#if defined(HAVE_GETPWENT)
  endpwent ();		/* some systems need this */
#endif

  return (home_dir);
#else
  abort();
  return 0;
#endif
}

#if !defined(O_NDELAY)
#if defined(FNDELAY)
#define O_NDELAY FNDELAY
#endif
#endif

int sh_unset_nodelay_mode(int fd)
{
#if defined(HAVE_FCNTL)
  int flags, bflags;

  if ((flags= fcntl(fd, F_GETFL, 0)) < 0)
    return -1;

  bflags= 0;

#ifdef O_NONBLOCK
  bflags|= O_NONBLOCK;
#endif

#ifdef O_NDELAY
  bflags|= O_NDELAY;
#endif

  if (flags & bflags)
  {
    flags&= ~bflags;
    return (fcntl(fd, F_SETFL, flags));
  }
#endif

  return 0;
}