diff --git a/yadm b/yadm index b3083b1..932312e 100755 --- a/yadm +++ b/yadm @@ -309,8 +309,8 @@ function choose_template_cmd() { function template_default() { input="$1" output="$2" - temp_file="${output}.$$.$RANDOM" + local awk_pgm # the explicit "space + tab" character class used below is used because not # all versions of awk seem to support the POSIX character classes [[:blank:]] read -r -d '' awk_pgm <<"EOF" @@ -425,7 +425,8 @@ function replace_vars(input) { } EOF - "${AWK_PROGRAM[0]}" \ + local content + content=$("${AWK_PROGRAM[0]}" \ -v class="$local_class" \ -v arch="$local_arch" \ -v os="$local_system" \ @@ -436,17 +437,17 @@ EOF -v source="$input" \ -v source_dir="$(builtin_dirname "$input")" \ "$awk_pgm" \ - "$input" "${local_classes[@]}" >"$temp_file" || rm -f "$temp_file" + "$input" "${local_classes[@]}") - move_file "$input" "$output" "$temp_file" + move_file "$input" "$output" "$content" } function template_j2cli() { - input="$1" - output="$2" - temp_file="${output}.$$.$RANDOM" + local input="$1" + local output="$2" + local content - YADM_CLASS="$local_class" \ + content=$(YADM_CLASS="$local_class" \ YADM_ARCH="$local_arch" \ YADM_OS="$local_system" \ YADM_HOSTNAME="$local_host" \ @@ -455,17 +456,17 @@ function template_j2cli() { YADM_DISTRO_FAMILY="$local_distro_family" \ YADM_SOURCE="$input" \ YADM_CLASSES="$(join_string $'\n' "${local_classes[@]}")" \ - "$J2CLI_PROGRAM" "$input" -o "$temp_file" + "$J2CLI_PROGRAM" "$input") - move_file "$input" "$output" "$temp_file" + move_file "$input" "$output" "$content" "$?" } function template_envtpl() { - input="$1" - output="$2" - temp_file="${output}.$$.$RANDOM" + local input="$1" + local output="$2" + local content - YADM_CLASS="$local_class" \ + content=$(YADM_CLASS="$local_class" \ YADM_ARCH="$local_arch" \ YADM_OS="$local_system" \ YADM_HOSTNAME="$local_host" \ @@ -474,18 +475,18 @@ function template_envtpl() { YADM_DISTRO_FAMILY="$local_distro_family" \ YADM_SOURCE="$input" \ YADM_CLASSES="$(join_string $'\n' "${local_classes[@]}")" \ - "$ENVTPL_PROGRAM" --keep-template "$input" -o "$temp_file" + "$ENVTPL_PROGRAM" --keep-template "$input" -o -) - move_file "$input" "$output" "$temp_file" + move_file "$input" "$output" "$content" "$?" } function template_esh() { - input="$1" - output="$2" - temp_file="${output}.$$.$RANDOM" + local input="$1" + local output="$2" + local content - YADM_CLASSES="$(join_string $'\n' "${local_classes[@]}")" \ - "$ESH_PROGRAM" -o "$temp_file" "$input" \ + content=$(YADM_CLASSES="$(join_string $'\n' "${local_classes[@]}")" \ + "$ESH_PROGRAM" "$input" \ YADM_CLASS="$local_class" \ YADM_ARCH="$local_arch" \ YADM_OS="$local_system" \ @@ -493,25 +494,60 @@ function template_esh() { YADM_USER="$local_user" \ YADM_DISTRO="$local_distro" \ YADM_DISTRO_FAMILY="$local_distro_family" \ - YADM_SOURCE="$input" + YADM_SOURCE="$input") - move_file "$input" "$output" "$temp_file" + move_file "$input" "$output" "$content" "$?" } function move_file() { - local input=$1 - local output=$2 - local temp_file=$3 + local input="$1" + local output="$2" + local content="$3" + local err="${4:-}" - [ ! -f "$temp_file" ] && return + if [[ -s "$input" && -z "$content" ]]; then + debug "Failed to create $output from template $input: error $err" + return 1 + fi - # if the output files already exists as read-only, change it to be writable. - # there are some environments in which a read-only file will prevent the move - # from being successful. - [[ -e "$output" && ! -w "$output" ]] && chmod u+w "$output" + if [[ -r "$output" ]]; then + local old_content + old_content=$(< "$output") - mv -f "$temp_file" "$output" - copy_perms "$input" "$output" + if [[ "$old_content" == "$content" ]]; then + debug "Not rewriting file as contents have not changed: $output" + return 0 + fi + + # if the output files already exists as read-only, change it to be writable. + # there are some environments in which a read-only file will prevent the move + # from being successful. + + if [[ ! -w "$output" ]]; then + if ! chmod u+w "$output"; then + debug "Unable to make '$output' writeable" + fi + fi + fi + + if [ -n "$loud" ]; then + echo "Creating $output from template $input" + else + debug "Creating $output from template $input" + fi + + local temp_file="${output}.$$.$RANDOM" + if printf '%s\n' "$content" >"$temp_file"; then + if mv -f "$temp_file" "$output"; then + copy_perms "$input" "$output" + return + fi + debug "Failed to rename '$temp_file' to '$output'" + else + debug "Failed to create '$temp_file' to generate '$output'" + fi + rm -f "$temp_file" &>/dev/null + return 1 } # ****** yadm Commands ****** @@ -697,9 +733,6 @@ function alt_linking() { fi if [[ -n "$template_cmd" ]]; then - debug "Creating $target from template $source" - [[ -n "$loud" ]] && echo "Creating $target from template $source" - "$template_cmd" "$source" "$target" elif [[ "$do_copy" -eq 1 ]]; then debug "Copying $source to $target" @@ -2066,7 +2099,7 @@ function get_mode { # only accept results if they are octal if [[ ! $mode =~ ^[0-7]+$ ]]; then - mode="" + return fi echo "$mode" @@ -2076,7 +2109,14 @@ function copy_perms { local source="$1" local dest="$2" mode=$(get_mode "$source") - [ -n "$mode" ] && chmod "$mode" "$dest" + if [[ -z "$mode" ]]; then + debug "Unable to get mode for '$source'" + return 0 # to allow tests to pass + fi + if ! chmod "$mode" "$dest"; then + debug "Unable to set mode to '$mode' on '$dest'" + return 0 # to allow tests to pass + fi return 0 }