tg.sh

   1 #!/bin/sh
   2 # TopGit - A different patch queue manager
   3 # (c) Petr Baudis <pasky@suse.cz>  2008
   4 # GPLv2
   5
   6 TG_VERSION=0.9
   7
   8 # Update if you add any code that requires a newer version of git
   9 GIT_MINIMUM_VERSION=1.7.7.2
  10
  11 ## Auxiliary functions
  12
  13 info()
  14 {
  15         echo "${TG_RECURSIVE}tg: $*"
  16 }
  17
  18 die()
  19 {
  20         info "fatal: $*" >&2
  21         exit 1
  22 }
  23
  24 compare_versions()
  25 {
  26         separator=$1
  27         echo $3 | tr ${separator} '\n' | (for l in $(echo $2|tr ${separator} ' '); do
  28             read r || return 0
  29             [ $l -ge $r ] || return 1
  30             [ $l -gt $r ] && return 0
  31         done)
  32 }
  33
  34 precheck() {
  35         git_ver=$(git version)
  36         compare_versions . ${git_ver#git version} ${GIT_MINIMUM_VERSION} \
  37             || die "git version >= " ${GIT_MINIMUM_VERSION} required
  38 }
  39
  40 precheck
  41 [ "$1" = "precheck" ] && exit 0
  42
  43 # cat_file TOPIC:PATH [FROM]
  44 # cat the file PATH from branch TOPIC when FROM is empty.
  45 # FROM can be -i or -w, than the file will be from the index or worktree,
  46 # respectively. The caller should than ensure that HEAD is TOPIC, to make sense.
  47 cat_file()
  48 {
  49         path="$1"
  50         case "${2-}" in
  51         -w)
  52                 cat "$root_dir/${path#*:}"
  53                 ;;
  54         -i)
  55                 # ':file' means cat from index
  56                 git cat-file blob ":${path#*:}"
  57                 ;;
  58         '')
  59                 git cat-file blob "$path"
  60                 ;;
  61         *)
  62                 die "Wrong argument to cat_file: '$2'"
  63                 ;;
  64         esac
  65 }
  66
  67 # get tree for the committed topic
  68 get_tree_()
  69 {
  70         echo "$1"
  71 }
  72
  73 # get tree for the base
  74 get_tree_b()
  75 {
  76         echo "refs/top-bases/$1"
  77 }
  78
  79 # get tree for the index
  80 get_tree_i()
  81 {
  82         git write-tree
  83 }
  84
  85 # get tree for the worktree
  86 get_tree_w()
  87 {
  88         i_tree=$(git write-tree)
  89         (
  90                 # the file for --index-output needs to sit next to the
  91                 # current index file
  92                 : ${GIT_INDEX_FILE:="$git_dir/index"}
  93                 TMP_INDEX="$(mktemp "${GIT_INDEX_FILE}-tg.XXXXXX")"
  94                 git read-tree -m $i_tree --index-output="$TMP_INDEX" &&
  95                 GIT_INDEX_FILE="$TMP_INDEX" &&
  96                 export GIT_INDEX_FILE &&
  97                 git diff --name-only -z HEAD |
  98                         git update-index -z --add --remove --stdin &&
  99                 git write-tree &&
 100                 rm -f "$TMP_INDEX"
 101         )
 102 }
 103
 104 # strip_ref "$(git symbolic-ref HEAD)"
 105 # Output will have a leading refs/heads/ or refs/top-bases/ stripped if present
 106 strip_ref()
 107 {
 108         case "$1" in
 109                 refs/heads/*)
 110                         echo "${1#refs/heads/}"
 111                         ;;
 112                 refs/top-bases/*)
 113                         echo "${1#refs/top-bases/}"
 114                         ;;
 115                 *)
 116                         echo "$1"
 117         esac
 118 }
 119
 120 # pretty_tree NAME [-b | -i | -w]
 121 # Output tree ID of a cleaned-up tree without tg's artifacts.
 122 # NAME will be ignored for -i and -w, but needs to be present
 123 pretty_tree()
 124 {
 125         name=$1
 126         source=${2#?}
 127         git ls-tree --full-tree "$(get_tree_$source "$name")" |
 128                 awk -F '        ' '$2 !~ /^.top/' |
 129                 git mktree
 130 }
 131
 132 # setup_hook NAME
 133 setup_hook()
 134 {
 135         hook_call="\"\$($tg --hooks-path)\"/$1 \"\$@\""
 136         if [ -f "$git_dir/hooks/$1" ] &&
 137            fgrep -q "$hook_call" "$git_dir/hooks/$1"; then
 138                 # Another job well done!
 139                 return
 140         fi
 141         # Prepare incantation
 142         if [ -x "$git_dir/hooks/$1" ]; then
 143                 hook_call="$hook_call"' || exit $?'
 144         else
 145                 hook_call="exec $hook_call"
 146         fi
 147         # Don't call hook if tg is not installed
 148         hook_call="if which \"$tg\" > /dev/null; then $hook_call; fi"
 149         # Insert call into the hook
 150         {
 151                 echo "#!/bin/sh"
 152                 echo "$hook_call"
 153                 [ ! -s "$git_dir/hooks/$1" ] || cat "$git_dir/hooks/$1"
 154         } >"$git_dir/hooks/$1+"
 155         chmod a+x "$git_dir/hooks/$1+"
 156         mv "$git_dir/hooks/$1+" "$git_dir/hooks/$1"
 157 }
 158
 159 # setup_ours (no arguments)
 160 setup_ours()
 161 {
 162         if [ ! -s "$git_dir/info/attributes" ] || ! grep -q topmsg "$git_dir/info/attributes"; then
 163                 {
 164                         echo ".topmsg   merge=ours"
 165                         echo ".topdeps  merge=ours"
 166                 } >>"$git_dir/info/attributes"
 167         fi
 168         if ! git config merge.ours.driver >/dev/null; then
 169                 git config merge.ours.name '"always keep ours" merge driver'
 170                 git config merge.ours.driver 'touch %A'
 171         fi
 172 }
 173
 174 # measure_branch NAME [BASE]
 175 measure_branch()
 176 {
 177         _bname="$1"; _base="$2"
 178         [ -n "$_base" ] || _base="refs/top-bases/$_bname"
 179         # The caller should've verified $name is valid
 180         _commits="$(git rev-list "$_bname" ^"$_base" -- | wc -l)"
 181         _nmcommits="$(git rev-list --no-merges "$_bname" ^"$_base" -- | wc -l)"
 182         if [ $_commits -gt 1 ]; then
 183                 _suffix="commits"
 184         else
 185                 _suffix="commit"
 186         fi
 187         echo "$_commits/$_nmcommits $_suffix"
 188 }
 189
 190 # branch_contains B1 B2
 191 # Whether B1 is a superset of B2.
 192 branch_contains()
 193 {
 194         [ -z "$(git rev-list --max-count=1 ^"$1" "$2" --)" ]
 195 }
 196
 197 # ref_exists REF
 198 # Whether REF is a valid ref name
 199 ref_exists()
 200 {
 201         git rev-parse --verify "$@" >/dev/null 2>&1
 202 }
 203
 204 # has_remote BRANCH
 205 # Whether BRANCH has a remote equivalent (accepts top-bases/ too)
 206 has_remote()
 207 {
 208         [ -n "$base_remote" ] && ref_exists "remotes/$base_remote/$1"
 209 }
 210
 211 branch_annihilated()
 212 {
 213         _branch_name="$1";
 214
 215         # use the merge base in case the base is ahead.
 216         mb="$(git merge-base "refs/top-bases/$_branch_name" "$_branch_name" 2> /dev/null)";
 217
 218         test -z "$mb" || test "$(git rev-parse "$mb^{tree}")" = "$(git rev-parse "$_branch_name^{tree}")";
 219 }
 220
 221 non_annihilated_branches()
 222 {
 223         _pattern="$@"
 224         git for-each-ref ${_pattern:-refs/top-bases} |
 225                 while read rev type ref; do
 226                         name="${ref#refs/top-bases/}"
 227                         if branch_annihilated "$name"; then
 228                                 continue
 229                         fi
 230                         echo "$name"
 231                 done
 232 }
 233
 234 # Make sure our tree is clean
 235 ensure_clean_tree()
 236 {
 237         git update-index --ignore-submodules --refresh ||
 238                 die "the working directory has uncommitted changes (see above) - first commit or reset them"
 239         [ -z "$(git diff-index --cached --name-status -r --ignore-submodules HEAD --)" ] ||
 240                 die "the index has uncommited changes"
 241 }
 242
 243 # is_sha1 REF
 244 # Whether REF is a SHA1 (compared to a symbolic name).
 245 is_sha1()
 246 {
 247         [ "$(git rev-parse "$1")" = "$1" ]
 248 }
 249
 250 # recurse_deps CMD NAME [BRANCHPATH...]
 251 # Recursively eval CMD on all dependencies of NAME.
 252 # CMD can refer to $_name for queried branch name,
 253 # $_dep for dependency name,
 254 # $_depchain for space-seperated branch backtrace,
 255 # $_dep_missing boolean to check whether $_dep is present
 256 # and the $_dep_is_tgish boolean.
 257 # It can modify $_ret to affect the return value
 258 # of the whole function.
 259 # If recurse_deps() hits missing dependencies, it will append
 260 # them to space-separated $missing_deps list and skip them
 261 # affter calling CMD with _dep_missing set.
 262 # remote dependencies are processed if no_remotes is unset.
 263 recurse_deps()
 264 {
 265         _cmd="$1"; shift
 266         _name="$1"; # no shift
 267         _depchain="$*"
 268
 269         _depsfile="$(get_temp tg-depsfile)"
 270         # If no_remotes is unset check also our base against remote base.
 271         # Checking our head against remote head has to be done in the helper.
 272         if test -z "$no_remotes" && has_remote "top-bases/$_name"; then
 273                 echo "refs/remotes/$base_remote/top-bases/$_name" >>"$_depsfile"
 274         fi
 275
 276         # if the branch was annihilated, it is considered to have no dependencies
 277         if ! branch_annihilated "$_name"; then
 278                 #TODO: handle nonexisting .topdeps?
 279                 git cat-file blob "$_name:.topdeps" >>"$_depsfile";
 280         fi;
 281
 282         _ret=0
 283         while read _dep; do
 284                 _dep_missing=
 285                 if ! ref_exists "$_dep" ; then
 286                         # All hope is lost. Inform driver and continue
 287                         missing_deps="$missing_deps $_dep"
 288                         _dep_missing=1
 289                         eval "$_cmd"
 290                         continue
 291                 fi
 292
 293                 _dep_is_tgish=1
 294                 ref_exists "refs/top-bases/$_dep"  ||
 295                         _dep_is_tgish=
 296
 297                 # Shoo shoo, keep our environment alone!
 298                 [ -z "$_dep_is_tgish" ] ||
 299                         (recurse_deps "$_cmd" "$_dep" "$@") ||
 300                         _ret=$?
 301
 302                 eval "$_cmd"
 303         done <"$_depsfile"
 304         missing_deps="${missing_deps# }"
 305         return $_ret
 306 }
 307
 308 # branch_needs_update
 309 # This is a helper function for determining whether given branch
 310 # is up-to-date wrt. its dependencies. It expects input as if it
 311 # is called as a recurse_deps() helper.
 312 # In case the branch does need update, it will echo it together
 313 # with the branch backtrace on the output (see needs_update()
 314 # description for details) and set $_ret to non-zero.
 315 branch_needs_update()
 316 {
 317         if [ -n "$_dep_missing" ]; then
 318                 echo "! $_depchain"
 319                 return 0
 320         fi
 321
 322         _dep_base_update=
 323         if [ -n "$_dep_is_tgish" ]; then
 324                 branch_annihilated "$_dep" && return 0
 325
 326                 if has_remote "$_dep"; then
 327                         branch_contains "$_dep" "refs/remotes/$base_remote/$_dep" || _dep_base_update=%
 328                 fi
 329                 # This can possibly override the remote check result;
 330                 # we want to sync with our base first
 331                 branch_contains "$_dep" "refs/top-bases/$_dep" || _dep_base_update=:
 332         fi
 333
 334         if [ -n "$_dep_base_update" ]; then
 335                 # _dep needs to be synced with its base/remote
 336                 echo "$_dep_base_update $_dep $_depchain"
 337                 _ret=1
 338         elif [ -n "$_name" ] && ! branch_contains "refs/top-bases/$_name" "$_dep"; then
 339                 # Some new commits in _dep
 340                 echo "$_dep $_depchain"
 341                 _ret=1
 342         fi
 343 }
 344
 345 # needs_update NAME
 346 # This function is recursive; it outputs reverse path from NAME
 347 # to the branch (e.g. B_DIRTY B1 B2 NAME), one path per line,
 348 # inner paths first. Innermost name can be ':' if the head is
 349 # not in sync with the base, '%' if the head is not in sync
 350 # with the remote (in this order of priority) or '!' if depednecy
 351 # is missing.
 352 # It will also return non-zero status if NAME needs update.
 353 # If needs_update() hits missing dependencies, it will append
 354 # them to space-separated $missing_deps list and skip them.
 355 needs_update()
 356 {
 357         recurse_deps branch_needs_update "$@"
 358 }
 359
 360 # branch_empty NAME [-i | -w]
 361 branch_empty()
 362 {
 363         [ "$(pretty_tree "$1" -b)" = "$(pretty_tree "$1" ${2-})" ]
 364 }
 365
 366 # list_deps [-i | -w]
 367 # -i/-w apply only to HEAD
 368 list_deps()
 369 {
 370         head_from=${1-}
 371         head="$(git symbolic-ref -q HEAD)" ||
 372                 head="..detached.."
 373
 374         git for-each-ref refs/top-bases |
 375                 while read rev type ref; do
 376                         name="${ref#refs/top-bases/}"
 377                         if branch_annihilated "$name"; then
 378                                 continue;
 379                         fi
 380
 381                         from=$head_from
 382                         [ "refs/heads/$name" = "$head" ] ||
 383                                 from=
 384                         cat_file "$name:.topdeps" $from | while read dep; do
 385                                 dep_is_tgish=true
 386                                 ref_exists "refs/top-bases/$dep"  ||
 387                                         dep_is_tgish=false
 388                                 if ! "$dep_is_tgish" || ! branch_annihilated $dep; then
 389                                         echo "$name $dep"
 390                                 fi
 391                         done
 392                 done
 393 }
 394
 395 # switch_to_base NAME [SEED]
 396 switch_to_base()
 397 {
 398         _base="refs/top-bases/$1"; _seed="$2"
 399         # We have to do all the hard work ourselves :/
 400         # This is like git checkout -b "$_base" "$_seed"
 401         # (or just git checkout "$_base"),
 402         # but does not create a detached HEAD.
 403         git read-tree -u -m HEAD "${_seed:-$_base}"
 404         [ -z "$_seed" ] || git update-ref "$_base" "$_seed"
 405         git symbolic-ref HEAD "$_base"
 406 }
 407
 408 # Show the help messages.
 409 do_help()
 410 {
 411         if [ -z "$1" ] ; then
 412                 # This is currently invoked in all kinds of circumstances,
 413                 # including when the user made a usage error. Should we end up
 414                 # providing more than a short help message, then we should
 415                 # differentiate.
 416                 # Petr's comment: http://marc.info/?l=git&m=122718711327376&w=2
 417
 418                 ## Build available commands list for help output
 419
 420                 cmds=
 421                 sep=
 422                 for cmd in "@cmddir@"/tg-*; do
 423                         ! [ -r "$cmd" ] && continue
 424                         # strip directory part and "tg-" prefix
 425                         cmd="$(basename "$cmd")"
 426                         cmd="${cmd#tg-}"
 427                         cmds="$cmds$sep$cmd"
 428                         sep="|"
 429                 done
 430
 431                 echo "TopGit v$TG_VERSION - A different patch queue manager"
 432                 echo "Usage: tg ( help [<command>] | [-r <remote>] ($cmds) ...)"
 433         elif [ -r "@cmddir@"/tg-$1 ] ; then
 434                 setup_pager
 435                 @cmddir@/tg-$1 -h 2>&1 || :
 436                 echo
 437                 if [ -r "@sharedir@/tg-$1.txt" ] ; then
 438                         cat "@sharedir@/tg-$1.txt"
 439                 fi
 440         else
 441                 echo "`basename $0`: no help for $1" 1>&2
 442                 do_help
 443                 exit 1
 444         fi
 445 }
 446
 447 ## Pager stuff
 448
 449 # isatty FD
 450 isatty()
 451 {
 452         test -t $1
 453 }
 454
 455 # setup_pager
 456 # Spawn pager process and redirect the rest of our output to it
 457 setup_pager()
 458 {
 459         isatty 1 || return 0
 460
 461         # TG_PAGER = GIT_PAGER | PAGER | less
 462         # NOTE: GIT_PAGER='' is significant
 463         TG_PAGER=${GIT_PAGER-${PAGER-less}}
 464
 465         [ -z "$TG_PAGER"  -o  "$TG_PAGER" = "cat" ]  && return 0
 466
 467
 468         # now spawn pager
 469         export LESS="${LESS:-FRSX}"     # as in pager.c:pager_preexec()
 470
 471         # setup_pager should be called only once per command
 472         pager_fifo="${tg_tmp_dir:-${HOME}}/.tg-pager"
 473         mkfifo -m 600 "$pager_fifo"
 474
 475         "$TG_PAGER" < "$pager_fifo" &
 476         exec > "$pager_fifo"            # dup2(pager_fifo.in, 1)
 477
 478         # this is needed so e.g. `git diff` will still colorize it's output if
 479         # requested in ~/.gitconfig with color.diff=auto
 480         export GIT_PAGER_IN_USE=1
 481
 482         # atexit(close(1); wait pager)
 483         # deliberately overwrites the global EXIT trap
 484         trap "exec >&-; rm -rf \"${tg_tmp_dir:-${HOME}/.tg-pager}\"; wait" EXIT
 485 }
 486
 487 # get_temp NAME [-d]
 488 # creates a new temporary file (or directory with -d) in the global
 489 # temporary directory $tg_tmp_dir with pattern prefix NAME
 490 get_temp()
 491 {
 492         mktemp ${2-} "$tg_tmp_dir/$1.XXXXXX"
 493 }
 494
 495 ## Startup
 496
 497 [ -d "@cmddir@" ] ||
 498         die "No command directory: '@cmddir@'"
 499
 500 ## Initial setup
 501
 502 cmd="$1"
 503 [ -z "$tg__include" ] || cmd="include" # ensure setup happens
 504 case "$cmd" in
 505 help|--help|-h)
 506         :;;
 507 *)
 508         if [ -n "$cmd" ]; then
 509             set -e
 510             # suppress the merge log editor feature since git 1.7.10
 511             export GIT_MERGE_AUTOEDIT=no
 512             git_dir="$(git rev-parse --git-dir)"
 513             root_dir="$(git rev-parse --show-cdup)"; root_dir="${root_dir:-.}"
 514 # Make sure root_dir doesn't end with a trailing slash.
 515             root_dir="${root_dir%/}"
 516             base_remote="$(git config topgit.remote 2>/dev/null)" || :
 517             tg="tg"
 518 # make sure merging the .top* files will always behave sanely
 519             setup_ours
 520             setup_hook "pre-commit"
 521             # create global temporary directories, inside GIT_DIR
 522             tg_tmp_dir="$(mktemp -d "$git_dir/tg-tmp.XXXXXX")"
 523             trap "rm -rf \"$tg_tmp_dir\"" EXIT
 524         fi
 525 esac
 526
 527 ## Dispatch
 528
 529 # We were sourced from another script for our utility functions;
 530 # this is set by hooks.  Skip the rest of the file.  A simple return doesn't
 531 # work as expected in every shell.  See http://bugs.debian.org/516188
 532 if [ -z "$tg__include" ]; then
 533
 534 if [ "$1" = "-r" ]; then
 535         shift
 536         if [ -z "$1" ]; then
 537                 echo "Option -r requires an argument." >&2
 538                 do_help
 539                 exit 1
 540         fi
 541         base_remote="$1"; shift
 542         tg="$tg -r $base_remote"
 543 fi
 544
 545 [ -n "$cmd" ] || { do_help; exit 1; }
 546 shift
 547
 548 case "$cmd" in
 549 help|--help|-h)
 550         do_help "$1"
 551         exit 0;;
 552 --hooks-path)
 553         # Internal command
 554         echo "@hooksdir@";;
 555 *)
 556         [ -r "@cmddir@"/tg-$cmd ] || {
 557                 echo "Unknown subcommand: $cmd" >&2
 558                 do_help
 559                 exit 1
 560         }
 561         . "@cmddir@"/tg-$cmd;;
 562 esac
 563
 564 fi
 565
 566 # vim:noet