shell.c revision 47563 
1/* shell.c -- readline utility functions that are normally provided by
2	      bash when readline is linked as part of the shell. */
3
4/* Copyright (C) 1997 Free Software Foundation, Inc.
5
6   This file is part of the GNU Readline Library, a library for
7   reading lines of text with interactive input and history editing.
8
9   The GNU Readline Library is free software; you can redistribute it
10   and/or modify it under the terms of the GNU General Public License
11   as published by the Free Software Foundation; either version 1, or
12   (at your option) any later version.
13
14   The GNU Readline Library is distributed in the hope that it will be
15   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
16   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License for more details.
18
19   The GNU General Public License is often shipped with GNU software, and
20   is generally kept in a file called COPYING or LICENSE.  If you do not
21   have a copy of the license, write to the Free Software Foundation,
22   675 Mass Ave, Cambridge, MA 02139, USA. */
23#define READLINE_LIBRARY
24
25#if defined (HAVE_CONFIG_H)
26#  include <config.h>
27#endif
28
29#include <sys/types.h>
30
31#if defined (HAVE_UNISTD_H)
32#  include <unistd.h>
33#endif /* HAVE_UNISTD_H */
34
35#if defined (HAVE_STDLIB_H)
36#  include <stdlib.h>
37#else
38#  include "ansi_stdlib.h"
39#endif /* HAVE_STDLIB_H */
40
41#if defined (HAVE_STRING_H)
42#  include <string.h>
43#else
44#  include <strings.h>
45#endif /* !HAVE_STRING_H */
46
47#include <pwd.h>
48
49#if !defined (HAVE_GETPW_DECLS)
50extern struct passwd *getpwuid ();
51#endif /* !HAVE_GETPW_DECLS */
52
53extern char *xmalloc ();
54
55/* All of these functions are resolved from bash if we are linking readline
56   as part of bash. */
57
58/* Does shell-like quoting using single quotes. */
59char *
60single_quote (string)
61     char *string;
62{
63  register int c;
64  char *result, *r, *s;
65
66  result = (char *)xmalloc (3 + (3 * strlen (string)));
67  r = result;
68  *r++ = '\'';
69
70  for (s = string; s && (c = *s); s++)
71    {
72      *r++ = c;
73
74      if (c == '\'')
75	{
76	  *r++ = '\\';	/* insert escaped single quote */
77	  *r++ = '\'';
78	  *r++ = '\'';	/* start new quoted string */
79	}
80    }
81
82  *r++ = '\'';
83  *r = '\0';
84
85  return (result);
86}
87
88/* Set the environment variables LINES and COLUMNS to lines and cols,
89   respectively. */
90void
91set_lines_and_columns (lines, cols)
92     int lines, cols;
93{
94  char *b;
95
96#if defined (HAVE_PUTENV)
97  b = xmalloc (24);
98  sprintf (b, "LINES=%d", lines);
99  putenv (b);
100  b = xmalloc (24);
101  sprintf (b, "COLUMNS=%d", cols);
102  putenv (b);
103#else /* !HAVE_PUTENV */
104#  if defined (HAVE_SETENV)
105  b = xmalloc (8);
106  sprintf (b, "%d", lines);
107  setenv ("LINES", b, 1);
108  b = xmalloc (8);
109  sprintf (b, "%d", cols);
110  setenv ("COLUMNS", b, 1);
111#  endif /* HAVE_SETENV */
112#endif /* !HAVE_PUTENV */
113}
114
115char *
116get_env_value (varname)
117     char *varname;
118{
119  return ((char *)getenv (varname));
120}
121
122char *
123get_home_dir ()
124{
125  char *home_dir;
126  struct passwd *entry;
127
128  home_dir = (char *)NULL;
129  entry = getpwuid (getuid ());
130  if (entry)
131    home_dir = entry->pw_dir;
132  return (home_dir);
133}
134