tg-export.sh

   1 #!/bin/sh
   2 # TopGit - A different patch queue manager
   3 # (c) Petr Baudis <pasky@suse.cz>  2008
   4 # GPLv2
   5
   6 name=
   7 branches=
   8 output=
   9 driver=collapse
  10
  11
  12 ## Parse options
  13
  14 while [ -n "$1" ]; do
  15         arg="$1"; shift
  16         case "$arg" in
  17         -b)
  18                 branches="$1"; shift;;
  19         --quilt)
  20                 driver=quilt;;
  21         --collapse)
  22                 driver=collapse;;
  23         -*)
  24                 echo "Usage: tg [...] export ([--collapse] NEWBRANCH | [-b BRANCH1,BRANCH2...] --quilt DIRECTORY)" >&2
  25                 exit 1;;
  26         *)
  27                 [ -z "$output" ] || die "output already specified ($output)"
  28                 output="$arg";;
  29         esac
  30 done
  31
  32
  33
  34 [ -z "$branches" -o "$driver" = "quilt" ] ||
  35         die "-b works only with the quilt driver"
  36
  37 if [ -z "$branches" ]; then
  38         # this check is only needed when no branches have been passed
  39         name="$(git symbolic-ref HEAD | sed 's#^refs/heads/##')"
  40         base_rev="$(git rev-parse --short --verify "refs/top-bases/$name" 2>/dev/null)" ||
  41                 die "not on a TopGit-controlled branch"
  42         branches="$name"
  43 else
  44         name="${branches##*,}" # the last of the comma-separated items
  45 fi
  46 # $name holds the current branch
  47 # $branches holds the comma-separated list of branches
  48 # $name is equal to the last of the list of branches
  49
  50
  51 playground="$(mktemp -d -t tg-export.XXXXXX)"
  52 trap 'rm -rf "$playground"' EXIT
  53
  54
  55 ## Collapse driver
  56
  57 # pretty_tree NAME
  58 # Output tree ID of a cleaned-up tree without tg's artifacts.
  59 pretty_tree()
  60 {
  61         (export GIT_INDEX_FILE="$playground/^index"
  62          git read-tree "$1"
  63          git update-index --force-remove ".topmsg" ".topdeps"
  64          git write-tree)
  65 }
  66
  67 # collapsed_commit NAME
  68 # Produce a collapsed commit of branch NAME.
  69 collapsed_commit()
  70 {
  71         local name; name="$1"
  72
  73         rm -f "$playground/^pre" "$playground/^post"
  74         >"$playground/^body"
  75
  76         # Get commit message and authorship information
  77         git cat-file blob "$name:.topmsg" | git mailinfo "$playground/^msg" /dev/null > "$playground/^info"
  78
  79         GIT_AUTHOR_NAME="$(sed -n '/^Author/ s/Author: //p' "$playground/^info")"
  80         GIT_AUTHOR_EMAIL="$(sed -n '/^Email/ s/Email: //p' "$playground/^info")"
  81         GIT_AUTHOR_DATE="$(sed -n '/^Date/ s/Date: //p' "$playground/^info")"
  82         SUBJECT="$(sed -n '/^Subject/ s/Subject: //p' "$playground/^info")"
  83
  84         test -n "$GIT_AUTHOR_NAME" && export GIT_AUTHOR_NAME
  85         test -n "$GIT_AUTHOR_EMAIL" && export GIT_AUTHOR_EMAIL
  86         test -n "$GIT_AUTHOR_DATE" && export GIT_AUTHOR_DATE
  87
  88         # Determine parent
  89         parent="$(cut -f 1 "$playground/$name^parents")"
  90         if [ "$(cat "$playground/$name^parents" | wc -l)" -gt 1 ]; then
  91                 # Produce a merge commit first
  92                 parent="$({
  93                         echo "TopGit-driven merge of branches:"
  94                         echo
  95                         cut -f 2 "$playground/$name^parents"
  96                 } | git commit-tree "$(pretty_tree "refs/top-bases/$name")" \
  97                         $(for p in $parent; do echo -p $p; done))"
  98         fi
  99
 100         (printf '%s\n\n' "$SUBJECT"; cat "$playground/^msg") |
 101         git stripspace |
 102         git commit-tree "$(pretty_tree "$name")" -p "$parent"
 103
 104         echo "$name" >>"$playground/^ticker"
 105 }
 106
 107 # collapse
 108 # This will collapse a single branch, using information about
 109 # previously collapsed branches stored in $playground.
 110 collapse()
 111 {
 112         if [ -s "$playground/$_dep" ]; then
 113                 # We've already seen this dep
 114                 commit="$(cat "$playground/$_dep")"
 115
 116         elif [ -z "$_dep_is_tgish" ]; then
 117                 # This dep is not for rewrite
 118                 commit="$(git rev-parse --verify "$_dep")"
 119
 120         else
 121                 # First time hitting this dep; the common case
 122                 echo "Collapsing $_dep"
 123                 commit="$(collapsed_commit "$_dep")"
 124                 mkdir -p "$playground/$(dirname "$_dep")"
 125                 echo "$commit" >"$playground/$_dep"
 126         fi
 127
 128         # Propagate our work through the dependency chain
 129         mkdir -p "$playground/$(dirname "$_name")"
 130         echo "$commit   $_dep" >>"$playground/$_name^parents"
 131 }
 132
 133
 134 ## Quilt driver
 135
 136 quilt()
 137 {
 138         if [ -z "$_dep_is_tgish" ]; then
 139                 # This dep is not for rewrite
 140                 return
 141         fi
 142
 143         filename="$output/$_dep.diff"
 144         if [ -e "$filename" ]; then
 145                 # We've already seen this dep
 146                 return
 147         fi
 148
 149         echo "Exporting $_dep"
 150         mkdir -p "$(dirname "$filename")"
 151         $tg patch "$_dep" >"$filename"
 152         echo "$_dep.diff -p1" >>"$output/series"
 153 }
 154
 155
 156 ## Machinery
 157
 158 if [ "$driver" = "collapse" ]; then
 159         [ -n "$output" ] ||
 160                 die "no target branch specified"
 161         ! ref_exists "$output"  ||
 162                 die "target branch '$output' already exists; first run: git branch -D $output"
 163
 164 elif [ "$driver" = "quilt" ]; then
 165         [ -n "$output" ] ||
 166                 die "no target directory specified"
 167         [ ! -e "$output" ] ||
 168                 die "target directory already exists: $output"
 169
 170         mkdir -p "$output"
 171 fi
 172
 173
 174 driver()
 175 {
 176         case $_dep in refs/remotes/*) return;; esac
 177         branch_needs_update >/dev/null
 178         [ "$_ret" -eq 0 ] ||
 179                 die "cancelling export of $_dep (-> $_name): branch not up-to-date"
 180
 181         $driver
 182 }
 183
 184 # Call driver on all the branches - this will happen
 185 # in topological order.
 186 echo "$branches" | tr , '\n' | while read name; do
 187         recurse_deps driver "$name"
 188         (_ret=0; _dep="$name"; _name=""; _dep_is_tgish=1; driver)
 189 done
 190
 191 if [ "$driver" = "collapse" ]; then
 192         git update-ref "refs/heads/$output" "$(cat "$playground/$name")" ""
 193
 194         depcount="$(cat "$playground/^ticker" | wc -l)"
 195         echo "Exported topic branch $name (total $depcount topics) to branch $output"
 196
 197 elif [ "$driver" = "quilt" ]; then
 198         depcount="$(cat "$output/series" | wc -l)"
 199         echo "Exported topic branch $name (total $depcount topics) to directory $output"
 200 fi