rlm@1: #!/bin/bash
rlm@1: # Copyright (c) 2004 Matthias S. Benkmann <article AT winterdrache DOT de>
rlm@1: # You may do everything with this code except misrepresent its origin.
rlm@1: # PROVIDED `AS IS' WITH ABSOLUTELY NO WARRANTY OF ANY KIND!
rlm@1: 
rlm@1: #The following list should contain the mount points of all filesystems
rlm@1: #that are to be scanned as a space-separated list within parentheses. 
rlm@1: #/ will usually be in this list and if you have /usr
rlm@1: #on a separate partition, it will also be in this list. 
rlm@1: #Mount points whose filesystems are special, such as procfs or sysfs must
rlm@1: #not be in this list. While a simple find on those special filesystems should 
rlm@1: #be harmless, operations such as "-exec grep something" are NOT SAFE and may 
rlm@1: #have HARMFUL SIDE-EFFECTS, especially when performed as root. 
rlm@1: fs_to_scan=(/)
rlm@1: 
rlm@1: #Files with a path prefix found in the following list are ignored. As the
rlm@1: #main function of this script is to help you find files that contain
rlm@1: #hardwired paths to /tools or other unwanted references to
rlm@1: #your build system, you will usually prune any directories that don't contain
rlm@1: #files of interest, such as /tools (whose files naturally refer to /tools)
rlm@1: #and your package users' home directories (which may also test positive if
rlm@1: #you have unpacked and configured sources lying around).
rlm@1: #NOTE: The LFS-6.0 book uses a ramfs mounted on /dev and with that setup
rlm@1: #/dev does not need to be in the prune list. But since there is no requirement
rlm@1: #that /dev have its on filesystem it's better to prune it explicitly.
rlm@1: prune_prefixes=(/home /usr/src /dev /tools) #NO TRAILING SLASHES!!!
rlm@1: 
rlm@1: if [ $# -lt 1 -o "$1" = "--help" ]; then
rlm@1:   echo 1>&2 
rlm@1:   echo 1>&2 'USAGE: '"${0##*/}"' <grep-commands>'
rlm@1:   echo 1>&2 
rlm@1:   echo 1>&2 '  grep -l <grep-commands> -- <file>'
rlm@1:   echo 1>&2 '  will be executed for each *regular file* <file>'
rlm@1:   echo 1>&2 '  ATTENTION! If you override the -l switch with a switch that makes grep'
rlm@1:   echo 1>&2 '  output all individual matches rather than just the matching files,'
rlm@1:   echo 1>&2 '  then DO NOT redirect output to a file that is in a directory that will be'
rlm@1:   echo 1>&2 '  scanned, or you risk creating an endless loop that will cause your'
rlm@1:   echo 1>&2 '  output file to grow till your disk is full.'
rlm@1:   echo 1>&2 
rlm@1:   exit 1
rlm@1: fi
rlm@1: 
rlm@1: #suppress ugly debug output from shell
rlm@1: trap ':' SIGPIPE
rlm@1: 
rlm@1: #construct find commands that match the prune_prefixes. Each prefix will be
rlm@1: #matched as -path <prefix> -or -path <prefix>/*
rlm@1: #so that the directory itself and all subdirectories are matched.
rlm@1: y=(\( -false)
rlm@1: for ((i=0; $i<${#prune_prefixes[@]}; i=$i+1)) 
rlm@1: do
rlm@1:   y[${#y[@]}]='-or'
rlm@1:   y[${#y[@]}]=-path
rlm@1:   y[${#y[@]}]="${prune_prefixes[$i]}"
rlm@1:   y[${#y[@]}]='-or'
rlm@1:   y[${#y[@]}]=-path
rlm@1:   y[${#y[@]}]="${prune_prefixes[$i]}/*"
rlm@1: done
rlm@1: y[${#y[@]}]=')'
rlm@1: 
rlm@1: cmd_pre=(-type f -exec grep -l)
rlm@1: cmd_post=(-- {} \;)
rlm@1: 
rlm@1: #In the following find command, the part
rlm@1: # -not ( ( "${y[@]}" -prune ) -or "${y[@]}" )
rlm@1: #is responsible for preventing the files that match prune_prefixes from
rlm@1: #being processed. The 2nd "${y[@]}" may seem redundant, but it isn't, because
rlm@1: #-prune has no effect and is always false when -depth is used (which someone
rlm@1: #might do in the future).
rlm@1: #The -true before "$@" ensures that -depth can be passed as 1st parameter
rlm@1: #of $cmd_pre (should someone change it in the future).
rlm@1: find "${fs_to_scan[@]}" -xdev -noleaf \
rlm@1:      -not \( \( "${y[@]}" -prune \) -or "${y[@]}" \) \
rlm@1:      -and \( -true "${cmd_pre[@]}" "$@" "${cmd_post[@]}" \)