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 fi
  43
  44
  45 playground="$(mktemp -d -t tg-export.XXXXXX)"
  46 trap 'rm -rf "$playground"' EXIT
  47
  48
  49 ## Collapse driver
  50
  51 # pretty_tree NAME
  52 # Output tree ID of a cleaned-up tree without tg's artifacts.
  53 pretty_tree()
  54 {
  55         (export GIT_INDEX_FILE="$playground/^index"
  56          git read-tree "$1"
  57          git update-index --force-remove ".topmsg" ".topdeps"
  58          git write-tree)
  59 }
  60
  61 # collapsed_commit NAME
  62 # Produce a collapsed commit of branch NAME.
  63 collapsed_commit()
  64 {
  65         name="$1"
  66
  67         rm -f "$playground/^pre" "$playground/^post"
  68         >"$playground/^body"
  69
  70         # Get commit message and authorship information
  71         git cat-file blob "$name:.topmsg" | git mailinfo "$playground/^msg" /dev/null > "$playground/^info"
  72
  73         GIT_AUTHOR_NAME="$(sed -n '/^Author/ s/Author: //p' "$playground/^info")"
  74         GIT_AUTHOR_EMAIL="$(sed -n '/^Email/ s/Email: //p' "$playground/^info")"
  75         GIT_AUTHOR_DATE="$(sed -n '/^Date/ s/Date: //p' "$playground/^info")"
  76         SUBJECT="$(sed -n '/^Subject/ s/Subject: //p' "$playground/^info")"
  77
  78         test -n "$GIT_AUTHOR_NAME" && export GIT_AUTHOR_NAME
  79         test -n "$GIT_AUTHOR_EMAIL" && export GIT_AUTHOR_EMAIL
  80         test -n "$GIT_AUTHOR_DATE" && export GIT_AUTHOR_DATE
  81
  82         # Determine parent
  83         parent="$(cut -f 1 "$playground/$name^parents")"
  84         if [ "$(cat "$playground/$name^parents" | wc -l)" -gt 1 ]; then
  85                 # Produce a merge commit first
  86                 parent="$({
  87                         echo "TopGit-driven merge of branches:"
  88                         echo
  89                         cut -f 2 "$playground/$name^parents"
  90                 } | git commit-tree "$(pretty_tree "refs/top-bases/$name")" \
  91                         $(for p in $parent; do echo -p $p; done))"
  92         fi
  93
  94         if branch_empty "$name"; then
  95                 echo "$parent";
  96         else
  97                 (printf '%s\n\n' "$SUBJECT"; cat "$playground/^msg") |
  98                 git stripspace |
  99                 git commit-tree "$(pretty_tree "$name")" -p "$parent"
 100         fi;
 101
 102         echo "$name" >>"$playground/^ticker"
 103 }
 104
 105 # collapse
 106 # This will collapse a single branch, using information about
 107 # previously collapsed branches stored in $playground.
 108 collapse()
 109 {
 110         if [ -s "$playground/$_dep" ]; then
 111                 # We've already seen this dep
 112                 commit="$(cat "$playground/$_dep")"
 113
 114         elif [ -z "$_dep_is_tgish" ]; then
 115                 # This dep is not for rewrite
 116                 commit="$(git rev-parse --verify "$_dep")"
 117
 118         else
 119                 # First time hitting this dep; the common case
 120                 echo "Collapsing $_dep"
 121                 commit="$(collapsed_commit "$_dep")"
 122                 mkdir -p "$playground/$(dirname "$_dep")"
 123                 echo "$commit" >"$playground/$_dep"
 124         fi
 125
 126         # Propagate our work through the dependency chain
 127         mkdir -p "$playground/$(dirname "$_name")"
 128         echo "$commit   $_dep" >>"$playground/$_name^parents"
 129 }
 130
 131
 132 ## Quilt driver
 133
 134 quilt()
 135 {
 136         if [ -z "$_dep_is_tgish" ]; then
 137                 # This dep is not for rewrite
 138                 return
 139         fi
 140
 141         filename="$output/$_dep.diff"
 142         if [ -e "$filename" ]; then
 143                 # We've already seen this dep
 144                 return
 145         fi
 146
 147         if branch_empty "$_dep"; then
 148                 echo "Skip empty patch $_dep";
 149         else
 150                 echo "Exporting $_dep"
 151                 mkdir -p "$(dirname "$filename")"
 152                 $tg patch "$_dep" >"$filename"
 153                 echo "$_dep.diff -p1" >>"$output/series"
 154         fi
 155 }
 156
 157
 158 ## Machinery
 159
 160 if [ "$driver" = "collapse" ]; then
 161         [ -n "$output" ] ||
 162                 die "no target branch specified"
 163         ! ref_exists "$output"  ||
 164                 die "target branch '$output' already exists; first run: git branch -D $output"
 165
 166 elif [ "$driver" = "quilt" ]; then
 167         [ -n "$output" ] ||
 168                 die "no target directory specified"
 169         [ ! -e "$output" ] ||
 170                 die "target directory already exists: $output"
 171
 172         mkdir -p "$output"
 173 fi
 174
 175
 176 driver()
 177 {
 178         case $_dep in refs/remotes/*) return;; esac
 179         branch_needs_update >/dev/null
 180         [ "$_ret" -eq 0 ] ||
 181                 die "cancelling export of $_dep (-> $_name): branch not up-to-date"
 182
 183         $driver
 184 }
 185
 186 # Call driver on all the branches - this will happen
 187 # in topological order.
 188 if [ -z "$branches" ]; then
 189         recurse_deps driver "$name"
 190         (_ret=0; _dep="$name"; _name=""; _dep_is_tgish=1; driver)
 191 else
 192         echo "$branches" | tr ',' '\n' | while read _dep; do
 193                 _dep_is_tgish=1
 194                 $driver
 195         done
 196         name="$(echo "$branches" | sed 's/.*,//')"
 197 fi
 198
 199
 200 if [ "$driver" = "collapse" ]; then
 201         git update-ref "refs/heads/$output" "$(cat "$playground/$name")" ""
 202
 203         depcount="$(cat "$playground/^ticker" | wc -l)"
 204         echo "Exported topic branch $name (total $depcount topics) to branch $output"
 205
 206 elif [ "$driver" = "quilt" ]; then
 207         depcount="$(cat "$output/series" | wc -l)"
 208         echo "Exported topic branch $name (total $depcount topics) to directory $output"
 209 fi
 210
 211 # vim:noet