dotfiles

.bash_prompt (4236B)

---

 # Emacs?  -*- shell-script -*- please.
 
 # Environment variables:
 #
 # PS1_SHOWHOSTNAME
 #       'auto' (default):       Only show hostname over SSH
 #       'yes':                  Always show hostname
 #       anything else:          Never show hostname
 
 
 __show-hostname ()
 {
     case ${PS1_SHOWHOSTNAME} in
         (''|auto)
             test "${SSH_CONNECTION}";;
         (yes)
             true;;
         (*)
             false;;
     esac
 }
 
 __have-gitprompt ()
 {
     test -f /usr/lib/git-core/git-sh-prompt
 }
 
 __set-title ()
 {
     local title=${USER}
 
     __show-hostname && title+=@${HOSTNAME}
 
     # Empirically, no need to escape slashes in $HOME: Bash seems to
     # parse ${VAR/#PAT/REP} by (1) splitting VAR, PAT & REP (2) *then*
     # expanding PAT?
     title+=:${PWD/#${HOME}/\~}
 
     # Cf. console_codes(4):
     #
     #   ESC ] 2 ; txt ST        Set window title to txt.
     #
     # ST is a "string terminator", either "ESC \" or "BEL".
 
     printf $'\E]2;%s\a' "${title}"
 }
 
 # Bash relies on \[ \] to distinguish non-printing characters in prompts.
 __start-nonprinting ()
 {
     test ${BUILDING_PS} && printf '\['
 }
 
 __end-nonprinting ()
 {
     test ${BUILDING_PS} && printf '\]'
 }
 
 __fontify ()
 {
     local -r text=$1
     shift
 
     local -Ar codes=(
         [bold]=1
         [dim]=2
         [reverse]=7
         [red]=31
         [green]=32
         [blue]=34
     )
 
     local -a params=()
     local c
     for c
     do
         params+=(${codes[${c}]})
     done
 
     local params_seq
     IFS=';' eval 'params_seq="${params[*]}"'
 
     __start-nonprinting
     printf $'\E[%sm' "${params_seq}"
     __end-nonprinting
 
     printf %s "${text}"
 
     __start-nonprinting
     printf $'\E[0m'
     __end-nonprinting
 }
 
 __current-column ()
 {
     # Cf. console_codes(4) § ECMA-48 Status Report Commands.
 
     local position
     read -sdR -p$'\E[6n' position
 
     local -r pattern='\[[0-9]+;([0-9]+)'
 
     [[ ${position} =~ ${pattern} ]] || {
         echo 0
         return
     }
     echo ${BASH_REMATCH[1]}
 }
 
 __signal-no-newline ()
 {
     local -ir col=$(__current-column)
     ((col > 1)) || return
 
     __fontify ∅ bold red
     echo
 }
 
 __write-epilogue ()
 {
     local -ir rc=$1
     local -r rc_hex=$(printf %02x ${rc})
 
     local -r stamp=$(printf '%(%T)T')
 
     __fontify '[ ' dim
     if ((rc))
     then
         __fontify '$?:' dim red
         __fontify ${rc_hex} bold red
     else
         __fontify "\$?:${rc_hex}" dim
     fi
 
     __fontify " | ${stamp} ]" dim
     echo
 }
 
 __smart-term/set-ps1 ()
 {
     PS1=$(
         BUILDING_PS=t
         __fontify '\u' green
 
         __show-hostname && {
             __fontify @ dim
             __fontify '\H' bold green
         }
 
         printf ' '
 
         __fontify '\w' bold blue
 
         test "${PS1_SHOWGITSTATUS}" && {
             printf ' '
             __fontify "$(__git_ps1 '(%s)')" red
         }
 
         printf '\\n'
 
         __fontify '\$' dim
         printf ' '
     )
 }
 
 __smart-term/refresh ()
 {
     local -ir rc=$?
 
     __set-title
     __signal-no-newline
     __write-epilogue ${rc}
     __smart-term/set-ps1
 }
 
 __smart-term/init ()
 {
     # Prompts.
 
     __have-gitprompt && {
         . /usr/lib/git-core/git-sh-prompt
         GIT_PS1_SHOWDIRTYSTATE=t
         GIT_PS1_SHOWUPSTREAM=auto
 
         PS1_SHOWGITSTATUS=t
     }
 
     PROMPT_COMMAND=__smart-term/refresh
 
     PS2=$(
         BUILDING_PS=t
         __fontify '… ' dim
     )
 
     # Bindings.
 
     bind -f ~/.bash_inputrc
 
     # Unset the TTY's "stop" char, so that readline receives C-s.
     tty -s && stty stop ''
 }
 
 __dumb-term/refresh ()
 {
     local -ir rc=$?
     __write-epilogue ${rc}
 }
 
 __dumb-term/init ()
 {
     PROMPT_COMMAND=__dumb-term/refresh
     PS1='\W\$ '
 
     # I configure 'M-x shell' to use TERM=dumb-emacs-ansi; empirically
     # this makes Bash emit this bracketed paste sequence…
     #
     #     ^[[?2004l^M^J^[[?2004h
     #
     # … whenever I send a command in a nested shell ('bash' started
     # within the original shell, without --noediting).
     #
     # Until I figure something smarter:
     bind 'set enable-bracketed-paste off' 2>/dev/null
     # (Silence stderr: 'bind' complains when run with --noediting)
 }
 
 
 case "${TERM}"
 in
     dumb*)  __dumb-term/init ;;
     *)      __smart-term/init ;;
 esac