readline/shell.c

   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) 1997-2009,2017 Free Software Foundation, Inc.
   5
   6    This file is part of the GNU Readline Library (Readline), a library
   7    for reading lines of text with interactive input and history editing.
   8
   9    Readline is free software: you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation, either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    Readline is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with Readline.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  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 #if defined (HAVE_LIMITS_H)
  48 #  include <limits.h>
  49 #endif
  50
  51 #if defined (HAVE_FCNTL_H)
  52 #include <fcntl.h>
  53 #endif
  54 #if defined (HAVE_PWD_H)
  55 #include <pwd.h>
  56 #endif
  57
  58 #include <stdio.h>
  59
  60 #include "rlstdc.h"
  61 #include "rlshell.h"
  62 #include "rldefs.h"
  63
  64 #include "xmalloc.h"
  65
  66 #if defined (HAVE_GETPWUID) && !defined (HAVE_GETPW_DECLS)
  67 extern struct passwd *getpwuid PARAMS((uid_t));
  68 #endif /* HAVE_GETPWUID && !HAVE_GETPW_DECLS */
  69
  70 #ifndef NULL
  71 #  define NULL 0
  72 #endif
  73
  74 #ifndef CHAR_BIT
  75 #  define CHAR_BIT 8
  76 #endif
  77
  78 /* Nonzero if the integer type T is signed.  */
  79 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
  80
  81 /* Bound on length of the string representing an integer value of type T.
  82    Subtract one for the sign bit if T is signed;
  83    302 / 1000 is log10 (2) rounded up;
  84    add one for integer division truncation;
  85    add one more for a minus sign if t is signed.  */
  86 #define INT_STRLEN_BOUND(t) \
  87   ((sizeof (t) * CHAR_BIT - TYPE_SIGNED (t)) * 302 / 1000 \
  88    + 1 + TYPE_SIGNED (t))
  89
  90 /* All of these functions are resolved from bash if we are linking readline
  91    as part of bash. */
  92
  93 /* Does shell-like quoting using single quotes. */
  94 char *
  95 sh_single_quote (char *string)
  96 {
  97   register int c;
  98   char *result, *r, *s;
  99
 100   result = (char *)xmalloc (3 + (4 * strlen (string)));
 101   r = result;
 102   *r++ = '\'';
 103
 104   for (s = string; s && (c = *s); s++)
 105     {
 106       *r++ = c;
 107
 108       if (c == '\'')
 109         {
 110           *r++ = '\\';  /* insert escaped single quote */
 111           *r++ = '\'';
 112           *r++ = '\'';  /* start new quoted string */
 113         }
 114     }
 115
 116   *r++ = '\'';
 117   *r = '\0';
 118
 119   return (result);
 120 }
 121
 122 /* Set the environment variables LINES and COLUMNS to lines and cols,
 123    respectively. */
 124 static char setenv_buf[INT_STRLEN_BOUND (int) + 1];
 125 static char putenv_buf1[INT_STRLEN_BOUND (int) + 6 + 1];        /* sizeof("LINES=") == 6 */
 126 static char putenv_buf2[INT_STRLEN_BOUND (int) + 8 + 1];        /* sizeof("COLUMNS=") == 8 */
 127
 128 void
 129 sh_set_lines_and_columns (int lines, int cols)
 130 {
 131 #if defined (HAVE_SETENV)
 132   sprintf (setenv_buf, "%d", lines);
 133   setenv ("LINES", setenv_buf, 1);
 134
 135   sprintf (setenv_buf, "%d", cols);
 136   setenv ("COLUMNS", setenv_buf, 1);
 137 #else /* !HAVE_SETENV */
 138 #  if defined (HAVE_PUTENV)
 139   sprintf (putenv_buf1, "LINES=%d", lines);
 140   putenv (putenv_buf1);
 141
 142   sprintf (putenv_buf2, "COLUMNS=%d", cols);
 143   putenv (putenv_buf2);
 144 #  endif /* HAVE_PUTENV */
 145 #endif /* !HAVE_SETENV */
 146 }
 147
 148 char *
 149 sh_get_env_value (const char *varname)
 150 {
 151   return ((char *)getenv (varname));
 152 }
 153
 154 char *
 155 sh_get_home_dir (void)
 156 {
 157   static char *home_dir = (char *)NULL;
 158   struct passwd *entry;
 159
 160   if (home_dir)
 161     return (home_dir);
 162
 163   home_dir = (char *)NULL;
 164 #if defined (HAVE_GETPWUID)
 165 #  if defined (__TANDEM)
 166   entry = getpwnam (getlogin ());
 167 #  else
 168   entry = getpwuid (getuid ());
 169 #  endif
 170   if (entry)
 171     home_dir = savestring (entry->pw_dir);
 172 #endif
 173
 174 #if defined (HAVE_GETPWENT)
 175   endpwent ();          /* some systems need this */
 176 #endif
 177
 178   return (home_dir);
 179 }
 180
 181 #if !defined (O_NDELAY)
 182 #  if defined (FNDELAY)
 183 #    define O_NDELAY FNDELAY
 184 #  endif
 185 #endif
 186
 187 int
 188 sh_unset_nodelay_mode (int fd)
 189 {
 190 #if defined (HAVE_FCNTL)
 191   int flags, bflags;
 192
 193   if ((flags = fcntl (fd, F_GETFL, 0)) < 0)
 194     return -1;
 195
 196   bflags = 0;
 197
 198 #ifdef O_NONBLOCK
 199   bflags |= O_NONBLOCK;
 200 #endif
 201
 202 #ifdef O_NDELAY
 203   bflags |= O_NDELAY;
 204 #endif
 205
 206   if (flags & bflags)
 207     {
 208       flags &= ~bflags;
 209       return (fcntl (fd, F_SETFL, flags));
 210     }
 211 #endif
 212
 213   return 0;
 214 }