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 flatten=false
  11 numbered=false
  12
  13
  14 ## Parse options
  15
  16 while [ -n "$1" ]; do
  17         arg="$1"; shift
  18         case "$arg" in
  19         -b)
  20                 branches="$1"; shift;;
  21         --flatten)
  22                 flatten=true;;
  23         --numbered)
  24                 flatten=true;
  25                 numbered=true;;
  26         --quilt)
  27                 driver=quilt;;
  28         --collapse)
  29                 driver=collapse;;
  30         --linearize)
  31                 driver=linearize;;
  32         -*)
  33                 echo "Usage: tg [...] export ([--collapse] NEWBRANCH | [-b BRANCH1,BRANCH2...] --quilt DIRECTORY | --linearize NEWBRANCH)" >&2
  34                 exit 1;;
  35         *)
  36                 [ -z "$output" ] || die "output already specified ($output)"
  37                 output="$arg";;
  38         esac
  39 done
  40
  41
  42
  43 [ -z "$branches" -o "$driver" = "quilt" ] ||
  44         die "-b works only with the quilt driver"
  45
  46 [ "$driver" = "quilt" ] || ! "$numbered" ||
  47         die "--numbered works only with the quilt driver";
  48
  49 [ "$driver" = "quilt" ] || ! "$flatten" ||
  50         die "--flatten works only with the quilt driver"
  51
  52 if [ -z "$branches" ]; then
  53         # this check is only needed when no branches have been passed
  54         name="$(git symbolic-ref HEAD | sed 's#^refs/heads/##')"
  55         base_rev="$(git rev-parse --short --verify "refs/top-bases/$name" 2>/dev/null)" ||
  56                 die "not on a TopGit-controlled branch"
  57 fi
  58
  59
  60 playground="$(mktemp -d -t tg-export.XXXXXX)"
  61 trap 'rm -rf "$playground"' EXIT
  62
  63
  64 ## Collapse driver
  65
  66 # pretty_tree NAME
  67 # Output tree ID of a cleaned-up tree without tg's artifacts.
  68 pretty_tree()
  69 {
  70         (export GIT_INDEX_FILE="$playground/^index"
  71          git read-tree "$1"
  72          git update-index --force-remove ".topmsg" ".topdeps"
  73          git write-tree)
  74 }
  75
  76 create_tg_commit()
  77 {
  78         name="$1"
  79         tree="$2"
  80         parent="$3"
  81
  82         # Get commit message and authorship information
  83         git cat-file blob "$name:.topmsg" | git mailinfo "$playground/^msg" /dev/null > "$playground/^info"
  84
  85         GIT_AUTHOR_NAME="$(sed -n '/^Author/ s/Author: //p' "$playground/^info")"
  86         GIT_AUTHOR_EMAIL="$(sed -n '/^Email/ s/Email: //p' "$playground/^info")"
  87         GIT_AUTHOR_DATE="$(sed -n '/^Date/ s/Date: //p' "$playground/^info")"
  88         SUBJECT="$(sed -n '/^Subject/ s/Subject: //p' "$playground/^info")"
  89
  90         test -n "$GIT_AUTHOR_NAME" && export GIT_AUTHOR_NAME
  91         test -n "$GIT_AUTHOR_EMAIL" && export GIT_AUTHOR_EMAIL
  92         test -n "$GIT_AUTHOR_DATE" && export GIT_AUTHOR_DATE
  93
  94         (printf '%s\n\n' "$SUBJECT"; cat "$playground/^msg") |
  95         git stripspace |
  96         git commit-tree "$tree" -p "$parent"
  97 }
  98
  99 # collapsed_commit NAME
 100 # Produce a collapsed commit of branch NAME.
 101 collapsed_commit()
 102 {
 103         name="$1"
 104
 105         rm -f "$playground/^pre" "$playground/^post"
 106         >"$playground/^body"
 107
 108         # Determine parent
 109         parent="$(cut -f 1 "$playground/$name^parents")"
 110         if [ "$(cat "$playground/$name^parents" | wc -l)" -gt 1 ]; then
 111                 # Produce a merge commit first
 112                 parent="$({
 113                         echo "TopGit-driven merge of branches:"
 114                         echo
 115                         cut -f 2 "$playground/$name^parents"
 116                 } | git commit-tree "$(pretty_tree "refs/top-bases/$name")" \
 117                         $(for p in $parent; do echo -p $p; done))"
 118         fi
 119
 120         if branch_empty "$name"; then
 121                 echo "$parent";
 122         else
 123                 create_tg_commit "$name" "$(pretty_tree $name)" "$parent"
 124         fi;
 125
 126         echo "$name" >>"$playground/^ticker"
 127 }
 128
 129 # collapse
 130 # This will collapse a single branch, using information about
 131 # previously collapsed branches stored in $playground.
 132 collapse()
 133 {
 134         if [ -s "$playground/$_dep" ]; then
 135                 # We've already seen this dep
 136                 commit="$(cat "$playground/$_dep")"
 137
 138         elif [ -z "$_dep_is_tgish" ]; then
 139                 # This dep is not for rewrite
 140                 commit="$(git rev-parse --verify "$_dep")"
 141
 142         else
 143                 # First time hitting this dep; the common case
 144                 echo "Collapsing $_dep"
 145                 commit="$(collapsed_commit "$_dep")"
 146                 mkdir -p "$playground/$(dirname "$_dep")"
 147                 echo "$commit" >"$playground/$_dep"
 148         fi
 149
 150         # Propagate our work through the dependency chain
 151         mkdir -p "$playground/$(dirname "$_name")"
 152         echo "$commit   $_dep" >>"$playground/$_name^parents"
 153 }
 154
 155
 156 ## Quilt driver
 157
 158 quilt()
 159 {
 160         if [ -z "$_dep_is_tgish" ]; then
 161                 # This dep is not for rewrite
 162                 return
 163         fi
 164
 165         if "$flatten"; then
 166                 bn="$(echo "$_dep.diff" | sed -e 's#_#__#g' -e 's#/#_#g')";
 167                 dn="";
 168         else
 169                 bn="$(basename "$_dep.diff")";
 170                 dn="$(dirname "$_dep.diff")/";
 171                 if [ "x$dn" = "x./" ]; then
 172                         dn="";
 173                 fi;
 174         fi;
 175
 176         if [ -e "$playground/$_dep" ]; then
 177                 # We've already seen this dep
 178                 return
 179         fi
 180
 181         mkdir -p "$playground/$(dirname "$_dep")";
 182         touch "$playground/$_dep";
 183
 184         if branch_empty "$_dep"; then
 185                 echo "Skip empty patch $_dep";
 186         else
 187                 if "$numbered"; then
 188                         number="$(printf "%04u" $(($(cat "$playground/^number" 2>/dev/null) + 1)))";
 189                         bn="$number-$bn";
 190                         echo "$number" >"$playground/^number";
 191                 fi;
 192
 193                 echo "Exporting $_dep"
 194                 mkdir -p "$output/$dn";
 195                 $tg patch "$_dep" >"$output/$dn$bn"
 196                 echo "$dn$bn -p1" >>"$output/series"
 197         fi
 198 }
 199
 200 linearize()
 201 {
 202         if test ! -f "$playground/^BASE"; then
 203                 head="$(git rev-parse --verify "$_dep")"
 204                 echo "$head" > "$playground/^BASE"
 205                 git checkout -q "$head"
 206                 return;
 207         fi;
 208
 209         head=$(git rev-parse --verify HEAD)
 210
 211         if [ -z "$_dep_is_tgish" ]; then
 212                 # merge in $_dep unless already included
 213                 rev="$(git rev-parse --verify "$_dep")";
 214                 common="$(git merge-base --all HEAD "$_dep")";
 215                 if test "$rev" = "$common"; then
 216                         # already included, just skip
 217                         :;
 218                 else
 219                         retmerge=0;
 220
 221                         git merge -s recursive "$_dep" || retmerge="$?";
 222                         if test "x$retmerge" != "x0"; then
 223                                 echo fix up the merge, commit and then exit;
 224                                 #todo error handling
 225                                 sh -i </dev/tty;
 226                         fi;
 227                 fi;
 228         else
 229                 retmerge=0;
 230
 231                 git merge-recursive "$(pretty_tree "refs/top-bases/$_dep")" -- HEAD "$(pretty_tree "refs/heads/$_dep")" || retmerge="$?";
 232
 233                 if test "x$retmerge" != "x0"; then
 234                         git rerere;
 235                         echo "fix up the merge and update the index.  Don't commit!"
 236                         #todo error handling
 237                         sh -i </dev/tty;
 238                 fi
 239
 240                 result_tree=$(git write-tree)
 241                 # testing branch_empty might not always give the right answer.
 242                 # It can happen that the patch is non-empty but still after
 243                 # linearizing there is no change.  So compare the trees.
 244                 if test "x$result_tree" = "x$(git rev-parse $head^{tree})"; then
 245                         echo "skip empty commit $_dep";
 246                 else
 247                         newcommit=$(create_tg_commit "$_dep" "$result_tree" HEAD)
 248                         git update-ref HEAD $newcommit $head
 249                         echo "exported commit $_dep";
 250                 fi
 251         fi
 252 }
 253
 254 ## Machinery
 255
 256 if [ "$driver" = "collapse" ] || [ "$driver" = "linearize" ]; then
 257         [ -n "$output" ] ||
 258                 die "no target branch specified"
 259         ! ref_exists "$output"  ||
 260                 die "target branch '$output' already exists; first run: git branch -D $output"
 261
 262 elif [ "$driver" = "quilt" ]; then
 263         [ -n "$output" ] ||
 264                 die "no target directory specified"
 265         [ ! -e "$output" ] ||
 266                 die "target directory already exists: $output"
 267
 268         mkdir -p "$output"
 269 fi
 270
 271
 272 driver()
 273 {
 274         case $_dep in refs/remotes/*) return;; esac
 275         branch_needs_update >/dev/null
 276         [ "$_ret" -eq 0 ] ||
 277                 die "cancelling export of $_dep (-> $_name): branch not up-to-date"
 278
 279         $driver
 280 }
 281
 282 # Call driver on all the branches - this will happen
 283 # in topological order.
 284 if [ -z "$branches" ]; then
 285         recurse_deps driver "$name"
 286         (_ret=0; _dep="$name"; _name=""; _dep_is_tgish=1; driver)
 287 else
 288         echo "$branches" | tr ',' '\n' | while read _dep; do
 289                 _dep_is_tgish=1
 290                 $driver
 291         done
 292         name="$(echo "$branches" | sed 's/.*,//')"
 293 fi
 294
 295
 296 if [ "$driver" = "collapse" ]; then
 297         git update-ref "refs/heads/$output" "$(cat "$playground/$name")" ""
 298
 299         depcount="$(cat "$playground/^ticker" | wc -l)"
 300         echo "Exported topic branch $name (total $depcount topics) to branch $output"
 301
 302 elif [ "$driver" = "quilt" ]; then
 303         depcount="$(cat "$output/series" | wc -l)"
 304         echo "Exported topic branch $name (total $depcount topics) to directory $output"
 305
 306 elif [ "$driver" = "linearize" ]; then
 307         git checkout -q -b $output
 308
 309         echo $name
 310         if test $(git rev-parse "$(pretty_tree $name)^{tree}") != $(git rev-parse "HEAD^{tree}"); then
 311                 echo "Warning: Exported result doesn't match";
 312                 echo "tg-head=$(git rev-parse "$name"), exported=$(git rev-parse "HEAD")";
 313                 #git diff $head HEAD;
 314         fi;
 315
 316 fi
 317
 318 # vim:noet