terom@60: #!/bin/bash
terom@52: # vim: set ft=sh :
terom@52: #
terom@52: # Dependency-based updates + utils
terom@52: 
terom@52: ## Compare the given output file with all given source files:
terom@52: #
terom@52: #   check_update $out ${deps[@]} && do_update $out ... || ...
terom@52: #
terom@52: # Returns true if the output file needs to be updated.
terom@52: function check_update {
terom@52:     # target
terom@85:     local out="$1"; shift
terom@52: 
terom@52:     debug "$out"
terom@52: 
terom@52:     # need update?
terom@52:     local update=
terom@52: 
terom@52:     if [ ${#@} == 0 ]; then
terom@52:         debug "  update: unknown deps"
terom@52:         update=y
terom@52: 
terom@85:     elif [ ! -e "$out" ]; then
terom@52:         debug "  update: dest missing"
terom@52:         update=y
terom@52:         
terom@52:     elif [ $UPDATE_FORCE ]; then
terom@52:         debug "  update: forced"
terom@52:         update=y
terom@52:     fi
terom@52: 
terom@52:     # check deps
terom@52:     for dep in "$@"; do
terom@52:         # don't bother checking if already figured out
terom@52:         [ $update ] && continue
terom@52: 
terom@52:         # check
terom@84:         if [ ! -e "$dep" ]; then
terom@85:             warn "$out: Missing source: $dep"
terom@52: 
terom@85:         elif [ "$out" -ot "$dep" ]; then
terom@52:             debug "  update: $dep"
terom@52:             update=y
terom@52:         else
terom@52:             debug "  check: $dep"
terom@52:         fi
terom@52:     done
terom@52: 
terom@52:     [ ! $update ] && debug "  up-to-date"
terom@52: 
terom@52:     # return
terom@52:     [ $update ]
terom@52: }
terom@52: 
terom@52: ## Generate updated output file from given command's stdout:
terom@52: #
terom@52: #   do_update $out $BIN/cmd --args
terom@52: #
terom@52: # Writes output to a temporary .new file, optionally shows a diff of changes, and commits
terom@52: # the new version to $out (unless noop'd).
terom@52: function do_update {
terom@85:     local out="$1"; shift
terom@85:     local tmp="$out.new"
terom@52: 
terom@52:     debug "$out"
terom@85:     cmd "$@" > "$tmp"
terom@52: 
terom@52:     # compare
terom@85:     if [ -e "$out" ] && [ $UPDATE_DIFF ]; then
terom@52:         debug "  changes:"
terom@52: 
terom@52:         # terse
terom@85:         indent "        " diff --unified=1 "$out" "$tmp" || true
terom@52:     fi
terom@52:     
terom@52:     # deploy
terom@52:     if [ $UPDATE_NOOP ]; then
terom@52:         # cleanup
terom@52:         debug "  no-op"
terom@52: 
terom@85:         cmd rm "$tmp"
terom@52:     else
terom@52:         # commit
terom@52:         debug "  deploy"
terom@52: 
terom@85:         cmd mv "$tmp" "$out"
terom@52:     fi
terom@52: }
terom@52: 
terom@52: ## Compare symlink to target:
terom@52: #
terom@52: #   check_link $lnk $tgt && do_link $lnk $tgt || ...
terom@52: #
terom@52: # Tests if the symlink exists, and the target matches.
terom@52: # Fails if the target does not exist.
terom@52: function check_link {
terom@85:     local lnk="$1"
terom@85:     local tgt="$2"
terom@52: 
terom@85:     [ ! -e "$tgt" ] && fail "$tgt: target does not exist"
terom@52:     
terom@85:     [ ! -e "$lnk" ] || [ $(readlink "$lnk") != "$tgt" ]
terom@52: }
terom@52: 
terom@52: ## Update symlink to point to target:
terom@52: #
terom@52: #   do_link $lnk $tgt
terom@52: #
terom@52: function do_link {
terom@85:     local lnk="$1"
terom@85:     local tgt="$2"
terom@52: 
terom@85:     cmd ln -sf "$tgt" "$lnk"
terom@52: }
terom@52: 
terom@85: ## Read include paths from file
terom@85: function read_zone_includes {
terom@85:     cmd sed -n -E 's/^\$INCLUDE\s+"(.+)"/\1/p' "$@"
terom@85: }
terom@85: 
terom@85: ## (cached) include paths for zone file
terom@85: function zone_includes {
terom@85:     local cache="$1"
terom@85:     local src="$2"
terom@87:     local prefix="${3:-}"
terom@85: 
terom@85:     if [ ! -e "$cache" -o "$cache" -ot "$src" ]; then
terom@85:         read_zone_includes "$src" > "$cache"
terom@85:     fi
terom@85: 
terom@85:     while read include; do
terom@87:         echo -n "$prefix$include "
terom@85:     done < "$cache"
terom@85: }
terom@87: 
terom@87: ## Search for prefix-matching includes in zone file
terom@87: function zone_includes_grep {
terom@87:     local cache="$1"
terom@87:     local src="$2"
terom@87:     local prefix="$3"
terom@87:     
terom@87:     for include in $(zone_includes $cache $src); do
terom@87:         if [ "${include#$prefix}" != "$include" ]; then
terom@87:             echo -n " ${include#$prefix}"
terom@87:         fi
terom@87:     done
terom@87: }