chiark / gitweb /
Pass -- to diff-tree for branch/filename disambiguation
[topgit.git] / tg.sh
diff --git a/tg.sh b/tg.sh
index e7c42cd..43d1c9f 100644 (file)
--- a/tg.sh
+++ b/tg.sh
@@ -3,6 +3,7 @@
 # (c) Petr Baudis <pasky@suse.cz>  2008
 # GPLv2
 
+TG_VERSION=0.7
 
 ## Auxiliary functions
 
@@ -17,16 +18,37 @@ die()
        exit 1
 }
 
+# cat_file "topic:file"
+# Like `git cat-file blob $1`, but topics '(i)' and '(w)' means index and worktree
+cat_file()
+{
+       arg="$1"
+       case "$arg" in
+       '(w):'*)
+               arg=$(echo "$arg" | tail --bytes=+5)
+               cat "$arg"
+               return
+               ;;
+       '(i):'*)
+               # ':file' means cat from index
+               arg=$(echo "$arg" | tail --bytes=+5)
+               git cat-file blob ":$arg"
+               ;;
+       *)
+               git cat-file blob "$arg"
+       esac
+}
+
 # setup_hook NAME
 setup_hook()
 {
-       hook_call="\"\$(tg --hooks-path)\"/$1 \"\$@\""
+       hook_call="\"\$($tg --hooks-path)\"/$1 \"\$@\""
        if [ -f "$git_dir/hooks/$1" ] &&
           fgrep -q "$hook_call" "$git_dir/hooks/$1"; then
                # Another job well done!
                return
        fi
-       # Prepare incanation
+       # Prepare incantation
        if [ -x "$git_dir/hooks/$1" ]; then
                hook_call="$hook_call"' || exit $?'
        else
@@ -45,11 +67,11 @@ setup_hook()
 # setup_ours (no arguments)
 setup_ours()
 {
-       if [ ! -s "$git_dir/info/gitattributes" ] || ! grep -q topmsg "$git_dir/info/gitattributes"; then
+       if [ ! -s "$git_dir/info/attributes" ] || ! grep -q topmsg "$git_dir/info/attributes"; then
                {
-                       echo -e ".topmsg\tmerge=ours"
-                       echo -e ".topdeps\tmerge=ours"
-               } >>"$git_dir/info/gitattributes"
+                       echo ".topmsg   merge=ours"
+                       echo ".topdeps  merge=ours"
+               } >>"$git_dir/info/attributes"
        fi
        if ! git config merge.ours.driver >/dev/null; then
                git config merge.ours.name '"always keep ours" merge driver'
@@ -60,11 +82,11 @@ setup_ours()
 # measure_branch NAME [BASE]
 measure_branch()
 {
-       _name="$1"; _base="$2"
-       [ -n "$_base" ] || _base="refs/top-bases/$_name"
+       _bname="$1"; _base="$2"
+       [ -n "$_base" ] || _base="refs/top-bases/$_bname"
        # The caller should've verified $name is valid
-       _commits="$(git rev-list "$_name" ^"$_base" | wc -l)"
-       _nmcommits="$(git rev-list --no-merges "$_name" ^"$_base" | wc -l)"
+       _commits="$(git rev-list "$_bname" ^"$_base" -- | wc -l)"
+       _nmcommits="$(git rev-list --no-merges "$_bname" ^"$_base" -- | wc -l)"
        if [ $_commits -gt 1 ]; then
                _suffix="commits"
        else
@@ -77,62 +99,134 @@ measure_branch()
 # Whether B1 is a superset of B2.
 branch_contains()
 {
-       [ -z "$(git rev-list ^"$1" "$2")" ]
+       [ -z "$(git rev-list --max-count=1 ^"$1" "$2" --)" ]
 }
 
-# needs_update NAME [BRANCHPATH...]
-# This function is recursive; it outputs reverse path from NAME
-# to the branch (e.g. B_DIRTY B1 B2 NAME), one path per line,
-# inner paths first. Innermost name can be ':' if the head is
-# not in sync with the base.
-# It will also return non-zero status if NAME needs update.
-# If needs_update() hits missing dependencies, it will append
+# ref_exists REF
+# Whether REF is a valid ref name
+ref_exists()
+{
+       git rev-parse --verify "$@" >/dev/null 2>&1
+}
+
+# has_remote BRANCH
+# Whether BRANCH has a remote equivalent (accepts top-bases/ too)
+has_remote()
+{
+       [ -n "$base_remote" ] && ref_exists "remotes/$base_remote/$1"
+}
+
+branch_annihilated()
+{
+       _name="$1";
+
+       # use the merge base in case the base is ahead.
+       mb="$(git merge-base "refs/top-bases/$_name" "$_name")";
+
+       test "$(git rev-parse "$mb^{tree}")" = "$(git rev-parse "$_name^{tree}")";
+}
+
+# recurse_deps CMD NAME [BRANCHPATH...]
+# Recursively eval CMD on all dependencies of NAME.
+# CMD can refer to $_name for queried branch name,
+# $_dep for dependency name,
+# $_depchain for space-seperated branch backtrace,
+# and the $_dep_is_tgish boolean.
+# It can modify $_ret to affect the return value
+# of the whole function.
+# If recurse_deps() hits missing dependencies, it will append
 # them to space-separated $missing_deps list and skip them.
-needs_update()
+recurse_deps()
 {
-       depsfile="$(mktemp)"
-       git cat-file blob "$1:.topdeps" >"$depsfile"
+       _cmd="$1"; shift
+       _name="$1"; # no shift
+       _depchain="$*"
+
+       _depsfile="$(mktemp -t tg-depsfile.XXXXXX)"
+       # Check also our base against remote base. Checking our head
+       # against remote head has to be done in the helper.
+       if has_remote "top-bases/$_name"; then
+               echo "refs/remotes/$base_remote/top-bases/$_name" >>"$_depsfile"
+       fi
+
+       # if the branch was annihilated, there exists no .topdeps file
+       if ! branch_annihilated "$_name"; then
+               #TODO: handle nonexisting .topdeps?
+               git cat-file blob "$_name:.topdeps" >>"$_depsfile";
+       fi;
+
        _ret=0
        while read _dep; do
-               if ! git rev-parse --verify "$_dep" >/dev/null 2>&1; then
+               if ! ref_exists "$_dep" ; then
                        # All hope is lost
                        missing_deps="$missing_deps $_dep"
                        continue
                fi
 
                _dep_is_tgish=1
-               git rev-parse --verify "refs/top-bases/$_dep" >/dev/null 2>&1 ||
+               ref_exists "refs/top-bases/$_dep"  ||
                        _dep_is_tgish=
 
                # Shoo shoo, keep our environment alone!
                [ -z "$_dep_is_tgish" ] ||
-                       (needs_update "$_dep" "$@") ||
+                       (recurse_deps "$_cmd" "$_dep" "$@") ||
                        _ret=$?
 
-               _dep_base_uptodate=1
-               if [ -n "$_dep_is_tgish" ]; then
-                       branch_contains "$_dep" "refs/top-bases/$_dep" || _dep_base_uptodate=
-               fi
-
-               if [ -z "$_dep_base_uptodate" ]; then
-                       # _dep needs to be synced with its base
-                       echo ": $_dep $*"
-                       _ret=1
-               elif ! branch_contains "refs/top-bases/$1" "$_dep"; then
-                       # Some new commits in _dep
-                       echo "$_dep $*"
-                       _ret=1
-               fi
-       done <"$depsfile"
+               eval "$_cmd"
+       done <"$_depsfile"
        missing_deps="${missing_deps# }"
-       rm "$depsfile"
+       rm "$_depsfile"
        return $_ret
 }
 
+# branch_needs_update
+# This is a helper function for determining whether given branch
+# is up-to-date wrt. its dependencies. It expects input as if it
+# is called as a recurse_deps() helper.
+# In case the branch does need update, it will echo it together
+# with the branch backtrace on the output (see needs_update()
+# description for details) and set $_ret to non-zero.
+branch_needs_update()
+{
+       _dep_base_update=
+       if [ -n "$_dep_is_tgish" ]; then
+               if has_remote "$_dep"; then
+                       branch_contains "$_dep" "refs/remotes/$base_remote/$_dep" || _dep_base_update=%
+               fi
+               # This can possibly override the remote check result;
+               # we want to sync with our base first
+               branch_contains "$_dep" "refs/top-bases/$_dep" || _dep_base_update=:
+       fi
+
+       if [ -n "$_dep_base_update" ]; then
+               # _dep needs to be synced with its base/remote
+               echo "$_dep_base_update $_dep $_depchain"
+               _ret=1
+       elif [ -n "$_name" ] && ! branch_contains "refs/top-bases/$_name" "$_dep"; then
+               # Some new commits in _dep
+               echo "$_dep $_depchain"
+               _ret=1
+       fi
+}
+
+# needs_update NAME
+# This function is recursive; it outputs reverse path from NAME
+# to the branch (e.g. B_DIRTY B1 B2 NAME), one path per line,
+# inner paths first. Innermost name can be ':' if the head is
+# not in sync with the base or '%' if the head is not in sync
+# with the remote (in this order of priority).
+# It will also return non-zero status if NAME needs update.
+# If needs_update() hits missing dependencies, it will append
+# them to space-separated $missing_deps list and skip them.
+needs_update()
+{
+       recurse_deps branch_needs_update "$@"
+}
+
 # branch_empty NAME
 branch_empty()
 {
-       [ -z "$(git diff-tree "refs/top-bases/$1" "$1" | fgrep -v "     .top")" ]
+       [ -z "$(git diff-tree "refs/top-bases/$1" "$1" -- | fgrep -v "  .top")" ]
 }
 
 # switch_to_base NAME [SEED]
@@ -148,38 +242,136 @@ switch_to_base()
        git symbolic-ref HEAD "$_base"
 }
 
+# Show the help messages.
+do_help()
+{
+       if [ -z "$1" ] ; then
+               # This is currently invoked in all kinds of circumstances,
+               # including when the user made a usage error. Should we end up
+               # providing more than a short help message, then we should
+               # differentiate.
+               # Petr's comment: http://marc.info/?l=git&m=122718711327376&w=2
+
+               ## Build available commands list for help output
+
+               cmds=
+               sep=
+               for cmd in "@cmddir@"/tg-*; do
+                       ! [ -r "$cmd" ] && continue
+                       # strip directory part and "tg-" prefix
+                       cmd="$(basename "$cmd")"
+                       cmd="${cmd#tg-}"
+                       cmds="$cmds$sep$cmd"
+                       sep="|"
+               done
+
+               echo "TopGit v$TG_VERSION - A different patch queue manager"
+               echo "Usage: tg [-r REMOTE] ($cmds|help) ..."
+       elif [ -r "@cmddir@"/tg-$1 ] ; then
+               @cmddir@/tg-$1 -h || :
+               echo
+               if [ -r "@sharedir@/tg-$1.txt" ] ; then
+                       cat "@sharedir@/tg-$1.txt"
+               fi
+       else
+               echo "`basename $0`: no help for $1" 1>&2
+               do_help
+               exit 1
+       fi
+}
+
+## Pager stuff
+
+# isatty FD
+isatty()
+{
+       test -t $1
+}
+
+# setup_pager
+# Spawn pager process and redirect the rest of our output to it
+setup_pager()
+{
+       isatty 1 || return 0
+
+       # TG_PAGER = GIT_PAGER | PAGER | less
+       # NOTE: GIT_PAGER='' is significant
+       TG_PAGER=${GIT_PAGER-${PAGER-less}}
+
+       [ -z "$TG_PAGER"  -o  "$TG_PAGER" = "cat" ]  && return 0
+
+
+       # now spawn pager
+       export LESS=${LESS:-FRSX}       # as in pager.c:pager_preexec()
+
+       _pager_fifo_dir="$(mktemp -t -d tg-pager-fifo.XXXXXX)"
+       _pager_fifo="$_pager_fifo_dir/0"
+       mkfifo -m 600 "$_pager_fifo"
+
+       "$TG_PAGER" < "$_pager_fifo" &
+       exec > "$_pager_fifo"           # dup2(pager_fifo.in, 1)
+
+       # this is needed so e.g. `git diff` will still colorize it's output if
+       # requested in ~/.gitconfig with color.diff=auto
+       export GIT_PAGER_IN_USE=1
+
+       # atexit(close(1); wait pager)
+       trap "exec >&-; rm \"$_pager_fifo\"; rmdir \"$_pager_fifo_dir\"; wait" EXIT
+}
+
+## Startup
+
+[ -d "@cmddir@" ] ||
+       die "No command directory: '@cmddir@'"
 
 ## Initial setup
 
 set -e
 git_dir="$(git rev-parse --git-dir)"
 root_dir="$(git rev-parse --show-cdup)"; root_dir="${root_dir:-.}"
+# Make sure root_dir doesn't end with a trailing slash.
+root_dir="${root_dir%/}"
+base_remote="$(git config topgit.remote 2>/dev/null)" || :
+tg="tg"
 # make sure merging the .top* files will always behave sanely
 setup_ours
 setup_hook "pre-commit"
 
-
 ## Dispatch
 
 # We were sourced from another script for our utility functions;
 # this is set by hooks.
 [ -z "$tg__include" ] || return 0
 
+if [ "$1" = "-r" ]; then
+       shift
+       if [ -z "$1" ]; then
+               echo "Option -r requires an argument." >&2
+               do_help
+               exit 1
+       fi
+       base_remote="$1"; shift
+       tg="$tg -r $base_remote"
+fi
+
 cmd="$1"
-[ -n "$cmd" ] || die "He took a duck in the face at two hundred and fifty knots"
+[ -n "$cmd" ] || { do_help; exit 1; }
 shift
 
 case "$cmd" in
-help)
-       echo "TopGit v0.1 - A different patch queue manager"
-       echo "Usage: tg (create|delete|info|patch|summary|update|help) ..."
-       exit 1;;
-create|delete|info|patch|summary|update)
-       . "@cmddir@"/tg-$cmd;;
+help|--help|-h)
+       do_help "$1"
+       exit 0;;
 --hooks-path)
        # Internal command
        echo "@hooksdir@";;
 *)
-       echo "Unknown subcommand: $cmd" >&2
-       exit 1;;
+       [ -r "@cmddir@"/tg-$cmd ] || {
+               echo "Unknown subcommand: $cmd" >&2
+               do_help
+               exit 1
+       }
+       . "@cmddir@"/tg-$cmd;;
 esac
+
+# vim:noet