iankelling.org Git - distro-setup/blob - .bashrc

   1 #!/bin/bash
   2 # Copyright (C) 2019 Ian Kelling
   3 # SPDX-License-Identifier: AGPL-3.0-or-later
   4
   5 # to debug
   6 #set -x
   7 # redirect output to log file. this doesn't work. todo figure out why
   8 #exec 1>>/a/tmp/bashlog
   9 #exec 2>>/a/tmp/bashlog
  10
  11
  12 # By default this file is sourced for ALL ssh commands. This is wonky.
  13 # Normally, this file is not sourced when a script is run, but we can
  14 # override that by having #!/bin/bash -l.  I want something similar for ssh
  15 # commands. when a local script runs an ssh command, this file should not be
  16 # sourced by default, but we should be able to override that.
  17 #
  18 # So here we test for conditions of a script under ssh and return if so.
  19 # And we don't keep the rest of the code in this file, because even
  20 # though we return, we already parsed the whole code, and as I develop
  21 # the code, the parsing can have errors, which can screw up cronjobs
  22 # etc. To test for an overriding condition, we have a few options. one
  23 # is to use an environment variable.  env variables sent across ssh are
  24 # strictly limited. ssh -t which sets $SSH_TTY, but within a script that
  25 # won't work because tty allocation will fail.  We could override an
  26 # obscure unused LC_var, like telephone, but I don't want to run into
  27 # some edge case where that messes things up. we could transfer a file
  28 # which we could test for, but I can't think of a way to make that
  29 # inherently limited to a single ssh command.  I choose to set SendEnv
  30 # and AcceptEnv ssh config vars to allow the environment variable
  31 # BASH_LOGIN_SHELL to propagate across ssh. This also requires that we
  32 # wrap ssh in interactive shells, because, once we export the var, it
  33 # will go into scripts and theres no way to automatically set it.
  34
  35
  36 # first conditions show that we are an ssh command without an interactive shell
  37 if [[ $SSH_CONNECTION ]] \
  38        && [[ $- == *c* ]] \
  39        && [[ ! $SSH_TTY ]] \
  40        && [[ $- != *i* ]] \
  41        && [[ $BASH_LOGIN_SHELL != true ]]; then
  42     return 0
  43 else
  44     if [[ -r /etc/profile ]]; then
  45         source /etc/profile
  46     fi
  47     _x=$(readlink -f ${BASH_SOURCE[0]})
  48     _x=${_x%/*}/brc
  49     if [[ -r $_x ]]; then
  50       # shellcheck source=./brc
  51         source $_x
  52     fi
  53 fi
  54 # ensure no bad programs appending to this file will have an affect
  55 return 0