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@52:     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@52:     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@52:         if [ ! -e $ROOT/$dep ]; then
terom@52:             fail "$dst: Missing source: $dep"
terom@52: 
terom@52:         elif [ $ROOT/$out -ot $ROOT/$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@52:     local out=$1; shift
terom@52:     local tmp=$out.new
terom@52: 
terom@52:     debug "$out"
terom@52:     cmd "$@" > $ROOT/$tmp
terom@52: 
terom@52:     # compare
terom@52:     if [ -e $ROOT/$out ] && [ $UPDATE_DIFF ]; then
terom@52:         debug "  changes:"
terom@52: 
terom@52:         # terse
terom@52:         indent "        " diff --unified=1 $ROOT/$out $ROOT/$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@52:         cmd rm $ROOT/$tmp
terom@52:     else
terom@52:         # commit
terom@52:         debug "  deploy"
terom@52: 
terom@52:         cmd mv $ROOT/$tmp $ROOT/$out
terom@52:     fi
terom@52: }
terom@52: 
terom@52: ## Look for a link target:
terom@52: #
terom@52: #   find_link   $lnk    $tgt...
terom@52: #
terom@52: # Outputs the first given target to exist, skipping any that are the same as the given $lnk.
terom@52: # If no $tgt matches, outputs the last one, or '-'.
terom@52: function choose_link {
terom@52:     local lnk=$1; shift
terom@52:     local tgt=-
terom@52: 
terom@52:     for tgt in "$@"; do
terom@52:         [ $tgt != $out ] && [ -e $ROOT/$tgt ] && break
terom@52:     done
terom@52:     
terom@52:     echo $tgt
terom@52: }
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@52:     local lnk=$1
terom@52:     local tgt=$2
terom@52: 
terom@52:     [ ! -e $ROOT/$tgt ] && fail "$tgt: target does not exist"
terom@52:     
terom@52:     [ ! -e $ROOT/$lnk ] || [ $(readlink $ROOT/$lnk) != $ROOT/$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@52:     local lnk=$1
terom@52:     local tgt=$2
terom@52: 
terom@52:     cmd ln -sf $ROOT/$tgt $ROOT/$lnk
terom@52: }
terom@52: 
terom@52: ## Update .serial number:
terom@52: #
terom@52: #   do_update_serial $serial
terom@52: #
terom@52: # Shows old/new serial on debug.
terom@52: function do_update_serial {
terom@52:     local serial=$1
terom@52: 
terom@52:     # read
terom@52:     local old=$(test -e $ROOT/$serial && cat $ROOT/$serial || echo '')
terom@52: 
terom@52: 
terom@52:     cmd $BIN/update-serial $ROOT/$serial
terom@52:     
terom@52:     # read
terom@52:     local new=$(cat $ROOT/$serial)
terom@52:         
terom@52:     debug "  $old -> $new"
terom@52: }
terom@52: 
terom@52: ## Perform `hg commit` for $DATA
terom@52: function do_commit {
terom@52:     local msg=$1
terom@52: 
terom@55:     [ $LOG_DIFF ] && indent "    " hg_diff
terom@52: 
terom@52:     hg_commit "$msg"
terom@52: }
terom@52: 
terom@52: