contrib/neutral.sh

   1 #!/usr/bin/env bash
   2 #
   3 # This is experiment on http://revctrl.org/NeutralInterface, implementing
   4 # the interface.
   5
   6 die() {
   7         echo "$@" >&2
   8         exit 1
   9 }
  10
  11 # Take a field name as an argument and check in the $interesting[] array
  12 # whether we should output it.
  13 interesting() {
  14         [ "${interesting[0]}" = '*' ] && return 0
  15         for field in "${interesting[@]}"; do
  16                 [ "$field" = "$1" ] && return 0
  17         done
  18         return 1
  19 }
  20
  21
  22 if [ ! "$1" ] || [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
  23         die http://revctrl.org/NeutralInterface
  24 fi
  25
  26 interesting=('*')
  27 if [ "$1" = "-s" ]; then
  28         shift; interesting=(${1//,/ }); shift
  29 fi
  30
  31 cmd="$1"; shift; args=("$@");
  32 interactive=
  33 [ "$cmd" = "-i" ] && interactive=1
  34
  35 while [ "$cmd" ]; do
  36         if [ "$cmd" = "-i" ]; then
  37                 : # nothing
  38
  39         elif [ "$cmd" = "version" ]; then
  40                 interesting "version" && echo "version:1:0"
  41
  42         elif [ "$cmd" = "identify" ]; then
  43                 interesting "type" && echo "type:3:git"
  44
  45         elif [ "$cmd" = "changeset" ]; then
  46                 [ "${args[0]}" ] || die "missing changeset id"
  47                 commit="$(git-rev-parse --verify "${args[0]}")" || die "bad changeset id"
  48                 interesting "identifier" && echo "identifier:40:$commit"
  49
  50                 interesting "parent" &&
  51                 for parent in $(git-rev-parse --verify "$commit"^); do
  52                         echo "parent:40:$parent"
  53                 done
  54
  55                 interesting "tag" &&
  56                 grep -r -l "$commit" ${GIT_DIR:-.git}/refs/tags |
  57                         while IFS=$'\n' read tag; do
  58                                 tag="${tag##*/}"
  59                                 echo "tag:${#tag}:$tag"
  60                         done
  61
  62                 # FIXME: doesn't handle filenames containing newlines
  63                 interesting "file" &&
  64                 echo $commit $(git-rev-parse --verify "$commit"^) |
  65                         git-diff-tree -r -m --stdin | grep ^: | cut -f 2- |
  66                         while IFS=$'\n' read file; do
  67                                 echo "file:${#file}:$file"
  68                         done
  69
  70                 if interesting "user" || interesting "date"; then
  71                         author="$(git-cat-file commit "$commit" | sed -n 's/^author //p;/^$/q')"
  72
  73                         if interesting "user"; then
  74                                 user="$(echo "$author" | sed 's/\([^<]* <[^>]*>\).*/\1/')"
  75                                 echo user:${#user}:"$user"
  76                         fi
  77
  78                         if interesting "date"; then
  79                                 date="$(echo "$author" | sed 's/[^<]* <[^>]*> \(.*\)/\1/')"
  80                                 echo date:${#date}:"$date"
  81                         fi
  82                 fi
  83
  84                 if interesting "description"; then
  85                         desc="$(git-cat-file commit "$commit" | sed -n '/^$/{:a n;p;b a}')"
  86                         echo description:${#desc}:"$desc"
  87                 fi
  88
  89         else
  90                 die "unknown command"
  91         fi
  92
  93         cmd=
  94         if [ "$interactive" ]; then
  95                 echo # terminate output
  96                 read cmd
  97                 interesting=('*')
  98                 cmdname="${cmd%%+*}"
  99                 if [ "$cmdname" != "$cmd" ]; then
 100                         fields="${cmd#*+}"
 101                         interesting=(${fields//,/ })
 102                         cmd="$cmdname"
 103                 fi
 104
 105                 args=()
 106                 while true; do
 107                         # do with bash, I guess.
 108                         IFS=$'\n' read arg
 109                         [ "$arg" ] || break
 110                         arglen="${arg%%:*}"
 111                         argval="${arg#*:}"
 112                         while [ "${#argval}" -lt "$arglen" ]; do
 113                                 IFS=$'\n' read argvalmore
 114                                 argval="$argval
 115 $argvalmore"
 116                         done
 117                         [ "${#argval}" -gt "$arglen" ] &&
 118                                 die "announced value length ($arglen) doesn't match what I really snapped (${#argval})"
 119                         args[${#args[@]}]=${arg#*:}
 120                 done
 121         fi
 122 done