examples/functions/kshenv

   1 #
   2 # .kshenv -- functions and aliases to provide the beginnings of a ksh
   3 #            environment for bash.
   4 #
   5 # Chet Ramey
   6 # chet@ins.CWRU.Edu
   7 #
   8
   9 #
  10 #  Copyright 2002 Chester Ramey
  11 #
  12 #   This program is free software; you can redistribute it and/or modify
  13 #   it under the terms of the GNU General Public License as published by
  14 #   the Free Software Foundation; either version 2, or (at your option)
  15 #   any later version.
  16 #
  17 #   TThis program is distributed in the hope that it will be useful,
  18 #   but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 #   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 #   GNU General Public License for more details.
  21 #
  22 #   You should have received a copy of the GNU General Public License
  23 #   along with this program; if not, write to the Free Software Foundation,
  24 #   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25
  26 #
  27 # These are definitions for the ksh compiled-in `exported aliases'.  There
  28 # are others, but we already have substitutes for them: "history", "type",
  29 # and "hash".
  30 #
  31 alias r="fc -s"
  32 alias functions="typeset -f"
  33 alias integer="typeset -i"
  34 alias nohup="nohup "
  35 alias command="command "
  36 alias stop="kill -s STOP"
  37 alias redirect="command exec"
  38 alias hist="fc"
  39
  40 #
  41 # An almost-ksh compatible `whence' command.  This is as hairy as it is
  42 # because of the desire to exactly mimic ksh (whose behavior was determined
  43 # empirically).
  44 #
  45 # This depends somewhat on knowing the format of the output of the bash
  46 # `builtin type' command.
  47 #
  48
  49 whence()
  50 {
  51         local vflag pflag fflag defarg c
  52         local path
  53
  54         vflag= aflag= pflag= fflag=
  55         path=
  56         if [ "$#" = "0" ] ; then
  57                 echo "whence: usage: whence [-afpv] name..." >&2
  58                 return 2
  59         fi
  60
  61         OPTIND=1
  62         while getopts "avfp" c
  63         do
  64                 case "$c" in
  65                 a) defarg=-a ;;
  66                 f) fflag=1 ;;   # no-op
  67                 p) pflag=1 ;;
  68                 v) vflag=1 ;;
  69                 ?) echo "whence: $1: unknown option" >&2
  70                    echo "whence: usage: whence [-afpv] name..." >&2
  71                    return 2 ;;
  72                 esac
  73         done
  74
  75         shift $(( $OPTIND - 1 ))
  76
  77         if [ "$#" = "0" ] ; then
  78                 echo "whence: usage: whence [-afpv] name..." >&2
  79                 return 2
  80         fi
  81
  82         for cmd
  83         do
  84                 if [ "$vflag" ]  ; then
  85                         if [ -z "$defarg" ]; then
  86                                 builtin type $cmd | sed 1q
  87                         else
  88                                 if builtin type $defarg -t $cmd | grep 'function$' >/dev/null 2>&1; then
  89                                         # HAIRY awk script to suppress
  90                                         # printing of function body -- could
  91                                         # do it with sed, but I don't have
  92                                         # that kind of time
  93                                         builtin type $defarg $cmd | awk '
  94 BEGIN {printit = 1;}
  95 $1 == "'$cmd'" && $2 == "()" {printit=0; next; }
  96 /^}$/ { if (printit == 0) printit=1 ; else print $0; next ; }
  97 /.*/ { if (printit) print $0; }'
  98                                 else
  99                                         builtin type $defarg $cmd
 100                                 fi
 101                         fi
 102                 else
 103                         path=$(builtin type $defarg -p $cmd)
 104                         if [ "$path" ] ; then
 105                                 echo $path
 106                         else
 107                                 case "$cmd" in
 108                                 /*) echo "" ;;
 109                                  *) case "$(builtin type -t $cmd)" in
 110                                     "") echo "" ;;
 111                                     *) echo "$cmd" ;;
 112                                     esac
 113                                     ;;
 114                                 esac
 115                         fi
 116                 fi
 117         done
 118         return 0
 119 }
 120
 121 #
 122 # For real ksh homeboy fanatics, redefine the `type' builtin with a ksh
 123 # version.
 124 #
 125 #type()
 126 #{
 127 #       whence -v "$*"
 128 #}
 129
 130 #
 131 # ksh-like `cd': cd [-LP] [dir [change]]
 132 #
 133 cd()
 134 {
 135         OPTIND=1
 136         while getopts "LP" opt
 137         do
 138                 case $opt in
 139                 L|P)    CDOPTS="$CDOPTS -$opt" ;;
 140                 *)      echo "$FUNCNAME: usage: $FUNCNAME [-LP] [dir] [change]" >&2
 141                         return 2;;
 142                 esac
 143         done
 144
 145         shift $(( $OPTIND - 1 ))
 146
 147         case $# in
 148         0)      builtin cd $CDOPTS "$HOME" ;;
 149         1)      builtin cd $CDOPTS "$@" ;;
 150         2)      old="$1" new="$2"
 151                 case "$PWD" in
 152                 *$old*) ;;
 153                 *)       echo "${0##*/}: $FUNCNAME: bad substitution" >&2 ; return 1 ;;
 154                 esac
 155
 156                 dir=${PWD//$old/$new}
 157
 158                 builtin cd $CDOPTS "$dir" && echo "$PWD"
 159
 160                 ;;
 161         *)      echo "${0##*/}: $FUNCNAME: usage: $FUNCNAME [-LP] [dir] [change]" >&2
 162                 return 2 ;;
 163         esac
 164 }
 165
 166 #
 167 # ksh print emulation
 168 #
 169 #       print [-Rnprsu[n]] [-f format] [arg ...]
 170 #
 171 #       -       end of options
 172 #       -R      BSD-style -- only accept -n, no escapes
 173 #       -n      do not add trailing newline
 174 #       -p      no-op (no coprocesses)
 175 #       -r      no escapes
 176 #       -s      print to the history file
 177 #       -u n    redirect output to fd n
 178 #       -f format       printf "$format" "$@"
 179 #
 180
 181 print()
 182 {
 183         local eflag=-e
 184         local nflag= fflag= c
 185         local fd=1
 186
 187         OPTIND=1
 188         while getopts "fRnprsu:" c
 189         do
 190                 case $c in
 191                 R)      eflag= ;;
 192                 r)      eflag= ;;
 193                 n)      nflag=-n ;;
 194                 s)      sflag=y ;;
 195                 f)      fflag=y ;;
 196                 u)      fd=$OPTARG ;;
 197                 p)      ;;
 198                 esac
 199         done
 200         shift $(( $OPTIND - 1 ))
 201
 202         if [ -n "$fflag" ]; then
 203                 builtin printf "$@" >&$fd
 204                 return
 205         fi
 206
 207         case "$sflag" in
 208         y)      builtin history -s "$*" ;;
 209         *)      builtin echo $eflag $nflag "$@" >&$fd
 210         esac
 211 }
 212
 213 # substring function
 214 # this function should be equivalent to the substring built-in which was
 215 # eliminated after the 06/29/84 version
 216 substring ()
 217 {
 218         local lpat flag str     #local variables
 219         set -f
 220         case $1 in
 221         -l|-L)
 222                 flag=$1
 223                 lpat=$2
 224                 shift 2
 225                 ;;
 226         esac
 227         # test for too few or too many arguments
 228         if [ x"$1" = x ] || [ $# -gt 2 ]; then
 229                 print -u2 'substring: bad argument count'
 230                 return 1
 231         fi
 232         str=$1
 233         if [ x"$flag" = x-l ]; then             #substring -l lpat
 234                 str=${str#$lpat}
 235         elif [ x"$flag" = x-L ]; then
 236                 str=${str##$lpat}               #substring -L lpat
 237         fi
 238
 239         if [ x"$2" != x ]; then
 240                 echo ${str%$2}
 241         else
 242                 echo $str
 243         fi
 244
 245         return 0
 246 }