PS1 hostname consistent hashing

.bash_profile

# Colors
txtred='\[\e[0;31m\]' # Red
txtgrn='\[\e[0;32m\]' # Green
txtylw='\[\e[0;33m\]' # Yellow
txtblu='\[\e[0;34m\]' # Blue
txtpur='\[\e[0;35m\]' # Purple
txtcyn='\[\e[0;36m\]' # Cyan
bldred='\[\e[1;31m\]' # Red
bldgrn='\[\e[1;32m\]' # Green
bldylw='\[\e[1;33m\]' # Yellow
bldblu='\[\e[1;34m\]' # Blue
bldpur='\[\e[1;35m\]' # Purple
bldcyn='\[\e[1;36m\]' # Cyan
undred='\[\e[4;31m\]' # Red
undgrn='\[\e[4;32m\]' # Green
undylw='\[\e[4;33m\]' # Yellow
undblu='\[\e[4;34m\]' # Blue
undpur='\[\e[4;35m\]' # Purple
undcyn='\[\e[4;36m\]' # Cyan

txtrst='\[\e[0m\]'    # Text Reset

hostcolors[0]=${txtred}
hostcolors[1]=${txtgrn}
hostcolors[2]=${txtylw}
hostcolors[3]=${txtblu}
hostcolors[4]=${txtpur}
hostcolors[5]=${txtcyn}
hostcolors[6]=${bldred}
hostcolors[7]=${bldgrn}
hostcolors[8]=${bldylw}
hostcolors[9]=${bldblu}
hostcolors[10]=${bldpur}
hostcolors[11]=${bldcyn}
hostcolors[12]=${undred}
hostcolors[13]=${undgrn}
hostcolors[14]=${undylw}
hostcolors[15]=${undblu}
hostcolors[16]=${undpur}
hostcolors[17]=${undcyn}

hostmd5=$(hostname | md5sum | tr -d ' -')
hosthex=0x${hostmd5}
hostmod=$((${hosthex} % 18))
hostcolor=${hostcolors[${hostmod#-}]}

# dirname (git-branch [git-status-indicator]) $
PROMPT="${txtrst}:\W \$(__git_ps1 '${txtrst}(${txtcyn}%s${txtrst}) ')${txtrst}\$ "

function exitstatus {
  if [ $? -eq 0 ]
  then
    export PS1="${txtgrn}✓ ${hostcolor}\h$PROMPT"
  else
    export PS1="${txtred}× ${hostcolor}\h$PROMPT"
  fi
}

export GIT_PS1_SHOWDIRTYSTATE='true'

# Preserve shell history between open shells,
# and collapse duplicates
export HISTCONTROL=erasedups
export HISTSIZE=10000
shopt -s histappend

# Check last command exit status, update prompt accordingly
PROMPT_COMMAND='exitstatus; history -a'
exitstatus