#!/bin/sh
# p4-init-env --- guess values for P4* env variables
# Author: Noah Friedman <friedman@splode.com>
# Public domain

# $Id: p4-init-env,v 1.16 2005/11/03 23:19:29 friedman Exp $

# Commentary:

# Output proper p4 environment variable settings based on subnet.
# These should be eval'ed by the calling shell.

# Usage: eval `p4-init-env {user} {-shell} {--override|--no-override}`
#
# user           Set P4USER to this user.
# -shell         Emit shell's syntax for setting variables (e.g. "-tcsh")
# --override     indicates that P4* variables will be redefined even if
#                they are already present in the environment.
# --no-override  Any P4* variable already inherited from the environment
#                will not be overridden.

# Code:

PATH=$PATH:/usr/ucb
export PATH

uid=`whoami`
logname=`logname 2> /dev/null`
home_basename=`echo "$HOME" | sed -e 's/.*\///'`

if [ -n "$logname" ]; then
  user=$logname
elif [ -n "$home_basename" ]; then
  user=$home_basename
else
  user=${SUDO_USER-${USER-${LOGNAME-$uid}}}
fi

hostname=${HOSTNAME-`hostname`}
hostname=`echo "$hostname" | sed -e 's/\..*//'`
shell=$SHELL

opt_user=
overridep=f
while : ; do
  case $# in 0) break ;; esac
  case $1 in
    --override    ) overridep=t ; shift ;;
    --no-override ) overridep=f ; shift ;;
    -*            ) shell=$1    ; shift ;;
    *             ) opt_user=$1 ; shift ;;
  esac
done

defconfig=${_def_P4CONFIG-$HOME/.p4.cfg}
if [ -f "$defconfig" ]; then
  # This can be used to determine subnet based on default route gateway
  SUBNET=`netstat -rn \
           | sed -n -e '/^default/b p' \
                    -e '/^0\.0\.0\.0/b p' \
                    -e d \
                    -e :p \
                    -e 's/[ 	][ 	]*/ /g' \
                    -e 's/^[^ ]* //' \
                    -e 's/ .*//' \
                    -e p -e q`

  _vars=`set | sed -e '/^P4/!d' -e 's/=.*//'`
  new=`unset $_vars _vars;
       . "$defconfig";
       set | sed -e '/^P4/!d' -e 's/^/_def_/'`
  eval "$new"
fi

# Set P4USER only if not already set, or override was specified.
case $overridep:${P4USER+set}:$opt_user in
  t:*:?* | f::?* ) P4USER=$opt_user ;;
  t:*:   | f:: )   P4USER=${_def_P4USER-$user} ;;
esac

case $overridep:${P4CLIENT+set} in
  t:* | f: ) P4CLIENT=${_def_P4CLIENT-$uid.$hostname} ;;
esac

case $overridep:${P4PORT+set} in
  t:* | f: )
    P4PORT=${_def_P4PORT-perforce}

    # Append default tcp port if missing.
    case $P4PORT in
      *:* ) : ;;
      * ) P4PORT=$P4PORT:1666 ;;
    esac
   ;;
esac

# Emit the right syntax based on login shell.
case $shell in
  *[/-]* )
    shell=`echo "$shell" \
            | sed -e '/\//s=^.*/==' \
                  -e '/^-/s/^-//'`
   ;;
esac

case $shell in
  csh | tcsh )
    echo "setenv P4USER   $P4USER;"
    echo "setenv P4PORT   $P4PORT;"
    echo "setenv P4CLIENT $P4CLIENT;"
   ;;
  perl )
    echo '$ENV{P4USER}="'"$P4USER"'";'
    echo '$ENV{P4PORT}="'"$P4PORT"'";'
    echo '$ENV{P4CLIENT}="'"$P4CLIENT"'";'
   ;;
  gdb )
    echo "set environment P4USER   $P4USER"
    echo "set environment P4PORT   $P4PORT"
    echo "set environment P4CLIENT $P4CLIENT"
   ;;
  emacs | rep | sawfish | clisp | scsh | guile )
    progn="progn"
    setenv="setenv"
    case $shell in
      scsh  | guile ) progn="begin"           ;;
      clisp | gcl   ) setenv="system::setenv" ;;
    esac
    echo "($progn"
    echo "  ($setenv \"P4USER\"   \"$P4USER\")"
    echo "  ($setenv \"P4PORT\"   \"$P4PORT\")"
    echo "  ($setenv \"P4CLIENT\" \"$P4CLIENT\"))"
   ;;
  * ) # sh, ksh, bash, zsh, es, rc; others?
    echo "P4USER=$P4USER;"
    echo "P4PORT=$P4PORT;"
    echo "P4CLIENT=$P4CLIENT;"
    case $shell in
      es | rc ) : ;;
      * ) echo "export P4USER P4PORT P4CLIENT;" ;;
    esac
  ;;
esac

# p4-init-env ends here